| 1. |
- Arndt, D. S., et al.
(författare)
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State of the Climate in 2016
- 2017
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Ingår i: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 98:8, s. S1-S280
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Tidskriftsartikel (refereegranskat)abstract
- In 2016, the dominant greenhouse gases released into Earth's atmosphere-carbon dioxide, methane, and nitrous oxide-continued to increase and reach new record highs. The 3.5 +/- 0.1 ppm rise in global annual mean carbon dioxide from 2015 to 2016 was the largest annual increase observed in the 58-year measurement record. The annual global average carbon dioxide concentration at Earth's surface surpassed 400 ppm (402.9 +/- 0.1 ppm) for the first time in the modern atmospheric measurement record and in ice core records dating back as far as 800000 years. One of the strongest El Nino events since at least 1950 dissipated in spring, and a weak La Nina evolved later in the year. Owing at least in part to the combination of El Nino conditions early in the year and a long-term upward trend, Earth's surface observed record warmth for a third consecutive year, albeit by a much slimmer margin than by which that record was set in 2015. Above Earth's surface, the annual lower troposphere temperature was record high according to all datasets analyzed, while the lower stratospheric temperature was record low according to most of the in situ and satellite datasets. Several countries, including Mexico and India, reported record high annual temperatures while many others observed near-record highs. A week-long heat wave at the end of April over the northern and eastern Indian peninsula, with temperatures surpassing 44 degrees C, contributed to a water crisis for 330 million people and to 300 fatalities. In the Arctic the 2016 land surface temperature was 2.0 degrees C above the 1981-2010 average, breaking the previous record of 2007, 2011, and 2015 by 0.8 degrees C, representing a 3.5 degrees C increase since the record began in 1900. The increasing temperatures have led to decreasing Arctic sea ice extent and thickness. On 24 March, the sea ice extent at the end of the growth season saw its lowest maximum in the 37-year satellite record, tying with 2015 at 7.2% below the 1981-2010 average. The September 2016 Arctic sea ice minimum extent tied with 2007 for the second lowest value on record, 33% lower than the 1981-2010 average. Arctic sea ice cover remains relatively young and thin, making it vulnerable to continued extensive melt. The mass of the Greenland Ice Sheet, which has the capacity to contribute similar to 7 m to sea level rise, reached a record low value. The onset of its surface melt was the second earliest, after 2012, in the 37-year satellite record. Sea surface temperature was record high at the global scale, surpassing the previous record of 2015 by about 0.01 degrees C. The global sea surface temperature trend for the 21st century-to-date of +0.162 degrees C decade(-1) is much higher than the longer term 1950-2016 trend of +0.100 degrees C decade(-1). Global annual mean sea level also reached a new record high, marking the sixth consecutive year of increase. Global annual ocean heat content saw a slight drop compared to the record high in 2015. Alpine glacier retreat continued around the globe, and preliminary data indicate that 2016 is the 37th consecutive year of negative annual mass balance. Across the Northern Hemisphere, snow cover for each month from February to June was among its four least extensive in the 47-year satellite record. Continuing a pattern below the surface, record high temperatures at 20-m depth were measured at all permafrost observatories on the North Slope of Alaska and at the Canadian observatory on northernmost Ellesmere Island. In the Antarctic, record low monthly surface pressures were broken at many stations, with the southern annular mode setting record high index values in March and June. Monthly high surface pressure records for August and November were set at several stations. During this period, record low daily and monthly sea ice extents were observed, with the November mean sea ice extent more than 5 standard deviations below the 1981-2010 average. These record low sea ice values contrast sharply with the record high values observed during 2012-14. Over the region, springtime Antarctic stratospheric ozone depletion was less severe relative to the 1991-2006 average, but ozone levels were still low compared to pre-1990 levels. Closer to the equator, 93 named tropical storms were observed during 2016, above the 1981-2010 average of 82, but fewer than the 101 storms recorded in 2015. Three basins-the North Atlantic, and eastern and western North Pacific-experienced above-normal activity in 2016. The Australian basin recorded its least active season since the beginning of the satellite era in 1970. Overall, four tropical cyclones reached the Saffir-Simpson category 5 intensity level. The strong El Nino at the beginning of the year that transitioned to a weak La Nina contributed to enhanced precipitation variability around the world. Wet conditions were observed throughout the year across southern South America, causing repeated heavy flooding in Argentina, Paraguay, and Uruguay. Wetter-than-usual conditions were also observed for eastern Europe and central Asia, alleviating the drought conditions of 2014 and 2015 in southern Russia. In the United States, California had its first wetter-than-average year since 2012, after being plagued by drought for several years. Even so, the area covered by drought in 2016 at the global scale was among the largest in the post-1950 record. For each month, at least 12% of land surfaces experienced severe drought conditions or worse, the longest such stretch in the record. In northeastern Brazil, drought conditions were observed for the fifth consecutive year, making this the longest drought on record in the region. Dry conditions were also observed in western Bolivia and Peru; it was Bolivia's worst drought in the past 25 years. In May, with abnormally warm and dry conditions already prevailing over western Canada for about a year, the human-induced Fort McMurray wildfire burned nearly 590000 hectares and became the costliest disaster in Canadian history, with $3 billion (U.S. dollars) in insured losses.
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| 2. |
- Arndt, D. S., et al.
(författare)
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STATE OF THE CLIMATE IN 2017
- 2018
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Ingår i: Bulletin of The American Meteorological Society - (BAMS). - : American Meteorological Society. - 0003-0007 .- 1520-0477. ; 99:8, s. S1-S310
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Forskningsöversikt (refereegranskat)
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| 3. |
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| 4. |
- Beal, Jacob, et al.
(författare)
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Robust estimation of bacterial cell count from optical density
- 2020
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Ingår i: Communications Biology. - : Springer Science and Business Media LLC. - 2399-3642. ; 3:1
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Tidskriftsartikel (refereegranskat)abstract
- Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data.
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| 5. |
- Blunden, Jessica, et al.
(författare)
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State of the Climate in 2012
- 2013
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Ingår i: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 94:8, s. S1-S258
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Tidskriftsartikel (refereegranskat)abstract
- For the first time in serveral years, the El Nino-Southern Oscillation did not dominate regional climate conditions around the globe. A weak La Ni a dissipated to ENSOneutral conditions by spring, and while El Nino appeared to be emerging during summer, this phase never fully developed as sea surface temperatures in the eastern conditions. Nevertheless, other large-scale climate patterns and extreme weather events impacted various regions during the year. A negative phase of the Arctic Oscillation from mid-January to early February contributed to frigid conditions in parts of northern Africa, eastern Europe, and western Asia. A lack of rain during the 2012 wet season led to the worst drought in at least the past three decades for northeastern Brazil. Central North America also experienced one of its most severe droughts on record. The Caribbean observed a very wet dry season and it was the Sahel's wettest rainy season in 50 years. Overall, the 2012 average temperature across global land and ocean surfaces ranked among the 10 warmest years on record. The global land surface temperature alone was also among the 10 warmest on record. In the upper atmosphere, the average stratospheric temperature was record or near-record cold, depending on the dataset. After a 30-year warming trend from 1970 to 1999 for global sea surface temperatures, the period 2000-12 had little further trend. This may be linked to the prevalence of La Ni a-like conditions during the 21st century. Heat content in the upper 700 m of the ocean remained near record high levels in 2012. Net increases from 2011 to 2012 were observed at 700-m to 2000-m depth and even in the abyssal ocean below. Following sharp decreases in to the effects of La Ni a, sea levels rebounded to reach records highs in 2012. The increased hydrological cycle seen in recent years continued, with more evaporation in drier locations and more precipitation in rainy areas. In a pattern that has held since 2004, salty areas of the ocean surfaces and subsurfaces were anomalously salty on average, while fresher areas were anomalously fresh. Global tropical cyclone activity during 2012 was near average, with a total of 84 storms compared with the 1981-2010 average of 89. Similar to 2010 and 2011, the North Atlantic was the only hurricane basin that experienced above-normal activity. In this basin, Sandy brought devastation to Cuba and parts of the eastern North American seaboard. All other basins experienced either near-or below-normal tropical cyclone activity. Only three tropical cyclones reached Category 5 intensity-all in Bopha became the only storm in the historical record to produce winds greater than 130 kt south of 7 N. It was also the costliest storm to affect the Philippines and killed more than 1000 residents. Minimum Arctic sea ice extent in September and Northern Hemisphere snow cover extent in June both reached new record lows. June snow cover extent is now declining at a faster rate (-17.6% per decade) than September sea ice extent (-13.0% per decade). Permafrost temperatures reached record high values in northernmost Alaska. A new melt extent record occurred on 11-12 July on the Greenland ice sheet; 97% of the ice sheet showed some form of melt, four times greater than the average melt for this time of year. The climate in Antarctica was relatively stable overall. The largest maximum sea ice extent since records begain in 1978 was observed in September 2012. In the stratosphere, warm air led to the second smallest ozone hole in the past two decades. Even so, the springtime ozone layer above Antarctica likely will not return to its early 1980s state until about 2060. Following a slight decline associated with the global 2 emissions from fossil fuel combustion and cement production reached a record 9.5 +/- 0.5 Pg C in 2011 and a new record of 9.7 +/- 0.5 Pg C is estimated for 2012. Atmospheric CO2 concentrations increased by 2.1 ppm in 2012, to 392.6 ppm. In spring 2012, 2 concentration exceeded 400 ppm at 7 of the 13 Arctic observation sites. Globally, other greenhouse gases including methane and nitrous oxide also continued to rise in concentration and the combined effect now represents a 32% increase in radiative forcing over a 1990 baseline. Concentrations of most ozone depleting substances continued to fall.
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| 6. |
- Bäckman, Eva, 1968-, et al.
(författare)
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Thioredoxin, produced by stromal cells retrieved from the lymph node microenvironment, rescues chronic lymphocytic leukemia cells from apoptosis in vitro
- 2007
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Ingår i: Haematologia. - : Ferrata Storti Foundation (Haematologica). - 0017-6559 .- 1568-5594 .- 0390-6078 .- 1592-8721. ; 92:11, s. 1495-1504
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Tidskriftsartikel (refereegranskat)abstract
- Background and Objectives: The redox-regulatory protein thioredoxin has several functions including transcriptional regulation, and antioxidant, cytokine, and chemokine activities. We have previously shown that extracellular thioredoxin protects B-cell chronic lymphocytic leukemia (CLL) cells from apoptosis in vitro. In this study we were interested to determine whether thioredoxin is produced by cells surrounding the CLL cells in the in vivo microenvironment and whether this cell-derived thioredoxin has any leukemia growth-promoting effect in vitro. Design and Methods: Lymph nodes from CLL patients (n=25) were analyzed for thioredoxin expression by immunohistology. Stromal cells purified from the lymph nodes were analyzed for thioredoxin secretion at the single cell level using an ELIspot assay. The survival effect of the stromal-derived thioredoxin was tested by co-culturing stromal- and CLL cells with and without Fab-fragments of an anti-thioredoxin antibody. Results: The results indicated that the thioredoxin production correlated with the amount of proliferating cells and was mainly localized to the proliferation centers (pseudofollicles) in the CLL lymph nodes. The leukemia cells per se showed minimal thioredoxin levels; in contrast, stromal cells strongly expressed thioredoxin. Purified primary stromal cells, which secreted extracellular thioredoxin, significantly protected the CLL cells from undergoing apoptosis in 72 h co-cultures. Interestingly, this anti-apoptotic effect could be abrogated by addition of Fab-fragments of an anti- thioredoxin antibody. Interpretation and Conclusions: In conclusion, we have shown that stromal cells in the lymph node microenvironment produce thioredoxin and that the thioredoxin production is localized to the proliferation centers of the CLL lymph nodes. In addition, thioredoxin produced by purified stromal cells rescued CLL cells from apoptosis in vitro.
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| 7. |
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| 8. |
- Dimberg, Lina Y., et al.
(författare)
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Stat1 activation attenuates IL-6 induced Stat3 activity but does not alter apoptosis sensitivity in multiple myeloma
- 2012
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Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 12, s. 318-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Multiple myeloma (MM) is at present an incurable malignancy, characterized by apoptosis-resistant tumor cells. Interferon (IFN) treatment sensitizes MM cells to Fas-induced apoptosis and is associated with an increased activation of Signal transducer and activator of transcription (Stat)1. The role of Stat1 in MM has not been elucidated, but Stat1 has in several studies been ascribed a pro-apoptotic role. Conversely, IL-6 induction of Stat3 is known to confer resistance to apoptosis in MM. Methods: To delineate the role of Stat1 in IFN mediated sensitization to apoptosis, sub-lines of the U-266-1970 MM cell line with a stable expression of the active mutant Stat1C were utilized. The influence of Stat1C constitutive transcriptional activation on endogenous Stat3 expression and activation, and the expression of apoptosis-related genes were analyzed. To determine whether Stat1 alone would be an important determinant in sensitizing MM cells to apoptosis, the U-266-1970-Stat1C cell line and control cells were exposed to high throughput compound screening (HTS). Results: To explore the role of Stat1 in IFN mediated apoptosis sensitization of MM, we established sublines of the MM cell line U-266-1970 constitutively expressing the active mutant Stat1C. We found that constitutive nuclear localization and transcriptional activity of Stat1 was associated with an attenuation of IL-6-induced Stat3 activation and up-regulation of mRNA for the pro-apoptotic Bcl-2 protein family genes Harakiri, the short form of Mcl-1 and Noxa. However, Stat1 activation alone was not sufficient to sensitize cells to Fas-induced apoptosis. In a screening of > 3000 compounds including bortezomib, dexamethasone, etoposide, suberoylanilide hydroxamic acid (SAHA), geldanamycin (17-AAG), doxorubicin and thalidomide, we found that the drug response and IC50 in cells constitutively expressing active Stat1 was mainly unaltered. Conclusion: We conclude that Stat1 alters IL-6 induced Stat3 activity and the expression of pro-apoptotic genes. However, this shift alone is not sufficient to alter apoptosis sensitivity in MM cells, suggesting that Stat1 independent pathways are operative in IFN mediated apoptosis sensitization.
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| 9. |
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| 10. |
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| 11. |
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| 12. |
- Grabowski, Pawel, 1975-, et al.
(författare)
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Telomere length as a prognostic parameter in chronic lymphocytic leukemia with special reference to VH gene mutation status
- 2005
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 105:12, s. 4807-4812
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Tidskriftsartikel (refereegranskat)abstract
- B-cell chronic lymphocytic leukemia (CLL) consists of 2 prognostic entities where cases with mutated immunoglobulin VH genes have better outcome than unmutated cases. VH-mutated CLLs display longer telomeres compared with unmutated cases and telomere length has been indicated to predict outcome, although the prognostic value of telomere length has not been fully established in CLL. We analyzed telomere length, VH gene mutation status, and clinical parameters in a large series of CLL. Telomere length was assessed by quantitative polymerase chain reaction (PCR), giving a very good correlation to telomere length estimated by Southern blotting (P < .001). The prognostic information given by mutation status (n = 282) and telomere length (n = 246) was significant (P < .001, respectively). Telomere length was a prognostic factor for stage A (P = .021) and stage B/C (P = .018) patients, whereas mutation status predicted outcome only in stage A patients (P < .001). Furthermore, mutated CLLs were subdivided by telomere length into 2 groups with different prognoses (P = .003), a subdivision not seen for unmutated cases (P = .232). Interestingly, the VH-mutated group with short telomeres had an overall survival close to that of the unmutated cases. Thus, by combining VH mutation status and telomere length, an improved subclassification of CLL was achieved identifying previously unrecognized patient groups with different outcomes.
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| 13. |
- Kaderi, Mohd Arifin, et al.
(författare)
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The GNAS1 T393C polymorphism and lack of clinical prognostic value in chronic lymphocytic leukemia
- 2008
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Ingår i: Leukemia Research. - : Elsevier BV. - 0145-2126 .- 1873-5835. ; 32:6, s. 984-987
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Tidskriftsartikel (refereegranskat)abstract
- Chronic lymphocytic leukemia (CLL) is a clinically heterogeneous disease with no known single predisposing genetic factor shown in all cases. Recently, a single nucleotide polymorphism (SNP) T393C in the GNAS1 gene has been reported to have a clinical impact on CLL progression and overall survival. In order to further investigate the T393C SNP in CLL, we have genotyped 279 CLL cases and correlated the genotypes to clinical outcome and other known prognostic factors such as the immunoglobulin heavy chain variable (IGHV) gene mutation status and CD38 expression. In the present study, no difference in overall survival or time to treatment was observed in the CLL patients with the different genotypes in contrast to the previous report. Furthermore, no correlation was observed with the T393C genotypes and IGHV mutational status, Binet stage or CD38 in this cohort. In summary, our data does not support the use of the T393C GNAS SNP as a clinical prognostic factor in CLL.
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| 14. |
- Kanduri, Meena, et al.
(författare)
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The novel NF-kappa B inhibitor IMD-0354 induces apoptosis in chronic lymphocytic leukemia
- 2011
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Ingår i: Blood Cancer Journal. - : Springer Science and Business Media LLC. - 2044-5385. ; 1, s. e12-
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Tidskriftsartikel (refereegranskat)abstract
- Nuclear factor-kappa B (NF-kappa B) is an important regulator of cell survival and has been shown to be constitutively active in chronic lymphocytic leukemia (CLL) cells. Recently, a novel NF-kappa B inhibitor, IMD-0354 (N-(3, 5-bis-trifluoromethyl-phenyl)-5-chloro-2-hydroxy-benzamide), was shown to specifically inhibit the phosphorylation of I kappa B alpha by IkB kinases, thus preventing NF-kappa B release. In this study, we investigated if IMD-0354 can inhibit NF-kappa B activation and induce apoptosis in CLL cells in vitro. The rate of increase in apoptosis, drug sensitivity and DNA-binding activity of NF-kappa B were studied using Annexin V stainings, the fluorometric microculture cytotoxicity assay and electrophoretic mobility shift assay, respectively. Finally, the impact of IMD-0354 treatment on the expression of a set of apoptosis-related genes was investigated. The results clearly show that IMD-0354 induced apoptosis (mean 26%, range 8-48%) in CLL cells, independent of immunoglobulin heavy variable (IGHV) gene mutational status, and showed a dose-dependent cytotoxic effect. IMD-0354 treatment also significantly lowered the DNA-binding activity of NF-kappa B in CLL cells. In addition, we identified differences in expression levels of pro- and antiapoptotic genes following IMD-0354 treatment. In summary, our novel findings show that IMD-0354 can induce apoptosis in CLL cells, and thus merits further investigation as an anticancer agent in vivo.
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| 15. |
- Lanemo Myhrinder, Anna, 1975-, et al.
(författare)
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A new perspective : molecular motifs on oxidized LDL, apoptotic cells, and bacteria are targets for chronic lymphocytic leukemia antibodies
- 2008
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 111:7, s. 3838-3848
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Tidskriftsartikel (refereegranskat)abstract
- The restricted immunoglobulin (Ig) repertoire found in B-cell chronic lymphocytic leukemia (CLL) implies a role for antigen(s) in the leukemogenesis. The nature of the antigens has, however, not been characterized, although examples of autoantigens have been demonstrated. We have analyzed a panel of 28 CLL cell lines and primary cultures, producing monoclonal Ig with different Ig heavy-chain variable region gene usage and mutational status, including several complementarity determining region 3 homology subset members. Using mass-spectrometry, immunoassays, or protein macroarrays, we have discovered novel antigens binding to CLL Igs. These antigens included cytoskeletal proteins vimentin, filamin B, and cofilin-1, but also phosphorylcholine-containing antigens (eg, Streptococcus pneumoniae polysaccharides and oxidized low-density lipoprotein [oxLDL]). Additional new antigens identified were cardiolipin and proline-rich acidic protein-1. Remarkably, these antigens represent molecular motifs exposed on apoptotic cells/blebs and bacteria, and several CLL Igs bound to apoptotic Jurkat cells. In conclusion, these intriguing data, showing a limited target structure recognition, indicate that CD5(+) CLL B cells are derived from a cell compartment that produces "natural antibodies," which may be instrumental in elimination and scavenging of apoptotic cells and pathogenic bacteria.
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| 16. |
- Lindhagen, Elin, et al.
(författare)
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In vitro activity of 20 agents in different prognostic subgroups of chronic lymphocytic leukaemia : rolipram and prednisolone active in cells from patients with poor prognosis
- 2009
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Ingår i: European Journal of Haematology. - : Wiley. - 0902-4441 .- 1600-0609. ; 83:1, s. 22-34
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Tidskriftsartikel (refereegranskat)abstract
- Background: There is a need for development of new drugs for treatment of B-cell chronic lymphocytic leukemia (CLL), especially for poor-prognostic subgroups resistant to conventional therapy. Objective: The in vitro antileukaemic activity of 20 different anticancer agents was characterized in tumour cells from CLL, aiming at identifying agents active in poor-prognostic subgroups.Design and methods: In tumour cells from 40 CLL patients and in peripheral blood mononuclear cells (PBMC) from 3 healthy controls, the activity of 20 substances was assessed using a non-clonogenic assay. The CLL samples were characterized regarding genomic aberrations by interphase FISH and immunoglobulin heavy-chain variable (IGHV) gene mutational status.Results:In line with clinical experience, cells from patients with unfavourable genomic aberrations (del(11q)/del(17p)) showed lower drug sensitivity to fludarabine and chlorambucil than cells from patients with favourable cytogenetics (del(13q)/no aberration). Most investigated drugs demonstrated similar activity in CLL cells from patients with unmutated and mutated IGHV genes as well as in CLL cells versus PBMC. Interestingly, prednisolone and rolipram displayed high CLL specificity, high activity in CLL cells with unmutated IGHV genes and retained the effect in several cases with 11q/17p deletion. Further studies on prednisolone and rolipram revealed a synergy when these agents were combined in CLL cells, and suggested correlation between drug sensitivity and difference in downstream signalling.Conclusion:Prednisolone and rolipram are interesting for further studies in CLL with inferior prognosis. The study can also be considered a basis for future efforts to find drugs active in subsets of CLL patients that are resistant to conventional therapy.
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| 17. |
- Mansouri, Mahmoud, et al.
(författare)
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Lipoprotein lipase is differentially expressed in prognostic subsets of chronic lymphocytic leukemia but displays invariably low catalytical activity
- 2010
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Ingår i: Leukemia Research. - : Elsevier BV. - 0145-2126 .- 1873-5835. ; 34:3, s. 301-306
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Tidskriftsartikel (refereegranskat)abstract
- Lipoprotein lipase (LPL) expression has been shown to correlate with IGHV mutational status and to predict outcome in chronic lymphocytic leukemia (CLL). We here investigated the prognostic impact of LPL expression in relation to other prognostic markers including IGHV3-21 usage in 140 CLL patients. Additionally, we studied the catalytic activity of LPL in CLL cells. A significant difference in LPL mRNA expression was detected in IGHV unmutated compared to mutated CLL patients (p<0.001). However, the poor-prognostic mutated/stereotyped IGHV3-21 patients did not differ from other mutated CLL cases. Clinical outcome was significantly different in CLL cases with high versus low LPL expression (p<0.001), and LPL expression exceeded mutation status/IGHV3-21 usage as an independent prognostic marker. Finally, LPL protein expression correlated significantly with mRNA expression and was higher in IGHV unmutated versus mutated CLL (p=0.018), although the majority of synthesized protein was catalytically inactive indicating a non-catalytical function in CLL.
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| 18. |
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| 19. |
- Murray, Fiona, 1980-
(författare)
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Stereotyped B Cell Receptors in Chronic Lymphocytic Leukaemia : Implications for Antigen Selection in Leukemogenesis
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Biased immunoglobulin heavy variable (IGHV) gene usage and distinctive B-cell receptor (BCR) features have been reported in chronic lymphocytic leukaemia (CLL), which may reflect clonal selection by antigens during disease development. Furthermore, the IGHV gene mutation status distinguishes two clinical entities of CLL, where patients with unmutated IGHV genes have an inferior prognosis compared to those with mutated IGHV genes. Recently, one subgroup of CLL patients expressing the IGHV3-21 gene was found to display highly similar immunoglobulin (IG) gene features, even within the heavy chain complementarity-determining region 3 (HCDR3). Patients in this subgroup typically had a poor prognosis.In paper I, we aimed to identify further subgroups with restricted BCR features among 346 CLL cases. Six subsets were defined which carried virtually identical BCRs in terms of rearranged heavy and light chain (LC) IG genes and CDR3 length and composition. In paper II, we investigated 90 IGHV3-21 cases from diverse geographical locations. We confirmed the highly restricted HCDR3 characteristics in 56% of patients and a biased usage of the IGLV3-21 gene in 72% of cases. Survival analysis also confirmed the poor outcome of this group, irrespective of IGHV gene mutation status and geographical origin.Papers III and IV involved a large-scale analysis of IGH and IG kappa and lambda (IGK/L) gene rearrangements, to define subsets with ‘stereotyped’ BCRs and also to systematically examine the somatic hypermutation (SHM) features of the IG genes in CLL. We studied a cohort of 1967 IGH and 891 IGK/L gene sequences from 1939 patients from 6 European institutions. Over 5300 IGH and ~4700 IGK/L sequences from non-CLL B cells were used as a control data set. In total, 110 CLL stereotyped subsets were defined according to HCDR3 homology. Striking IGK/L gene biases were also evident within subsets, along with distinctive K/LCDR3 features, such as length and amino acid composition. At cohort level, the patterns of mutation appeared to be consistent with that of a canonical SHM mechanism. However, at a subgroup level, certain stereotyped subsets, e.g. IGHV3-21/IGLV3-21 and IGHV4-34/IGKV2-30 CLL, deviated from this pattern. Furthermore, recurrent ‘stereotyped’ mutations occurred in cases belonging to subsets with restricted HCDR3s, in both IGHV and IGK/LV genes, which were subset- and CLL-biased when compared to non-CLL B cells.In conclusion, our findings implicate antigen selection as a significant factor in the pathogenesis of CLL, particularly in cases carrying stereotyped BCRs. The presence of stereotyped mutations throughout the VH and VL domain also indicates involvement of IG regions other than the CDR3 in antigen recognition. Finally, biased IGK/L gene usage and specific K/LCDR3 features are strong indications that LCs are crucial in shaping the specificity of leukemic BCRs, in association with defined heavy chains.
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| 20. |
- Murray, Fiona, et al.
(författare)
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Stereotyped patterns of somatic hypermutation in subsets of patients with chronic lymphocytic leukemia : implications for the role of antigen selection in leukemogenesis
- 2008
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 111:3, s. 1524-1533
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Tidskriftsartikel (refereegranskat)abstract
- Somatic hypermutation (SHM) features in a series of 1967 immunoglobulin heavy chain gene (IGH) rearrangements obtained from patients with chronic lymphocytic leukemia (CLL) were examined and compared with IGH sequences from non-CLL B cells available in public databases. SHM analysis was performed for all 1290 CLL sequences in this cohort with less than 100% identity to germ line. At the cohort level, SHM patterns were typical of a canonical SHM process. However, important differences emerged from the analysis of certain subgroups of CLL sequences defined by: (1) IGHV gene usage, (2) presence of stereotyped heavy chain complementarity-determining region 3 (HCDR3) sequences, and (3) mutational load. Recurrent, "stereotyped" amino acid changes occurred across the entire IGHV region in CLL subsets carrying stereotyped HCDR3 sequences, especially those expressing the IGHV3-21 and IGHV4-34 genes. These mutations are un-derrepresented among non-CLL sequences and thus can be considered as CLL-biased. Furthermore, it was shown that even a low level of mutations may be functionally relevant, given that stereotyped amino acid changes can be found in subsets of minimally mutated cases. The precise targeting and distinctive features of somatic hypermutation (SHM) in selected subgroups of CLL patients provide further evidence for selection by specific antigenic element(s).
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| 21. |
- Newton-Cheh, Christopher, et al.
(författare)
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Genome-wide association study identifies eight loci associated with blood pressure
- 2009
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1546-1718 .- 1061-4036. ; 41:6, s. 666-676
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Tidskriftsartikel (refereegranskat)abstract
- Elevated blood pressure is a common, heritable cause of cardiovascular disease worldwide. To date, identification of common genetic variants influencing blood pressure has proven challenging. We tested 2.5 million genotyped and imputed SNPs for association with systolic and diastolic blood pressure in 34,433 subjects of European ancestry from the Global BPgen consortium and followed up findings with direct genotyping (N <= 71,225 European ancestry, N <= 12,889 Indian Asian ancestry) and in silico comparison (CHARGE consortium, N 29,136). We identified association between systolic or diastolic blood pressure and common variants in eight regions near the CYP17A1 (P = 7 x 10(-24)), CYP1A2 (P = 1 x 10(-23)), FGF5 (P = 1 x 10(-21)), SH2B3 (P = 3 x 10(-18)), MTHFR (P = 2 x 10(-13)), c10orf107 (P = 1 x 10(-9)), ZNF652 (P = 5 x 10(-9)) and PLCD3 (P = 1 x 10(-8)) genes. All variants associated with continuous blood pressure were associated with dichotomous hypertension. These associations between common variants and blood pressure and hypertension offer mechanistic insights into the regulation of blood pressure and may point to novel targets for interventions to prevent cardiovascular disease.
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| 22. |
- Norberg, Maria, 1976-
(författare)
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In Vitro Drug Sensitivity and Apoptosis in Chronic Lymphocytic Leukemia
- 2010
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Chronic lymphocytic leukemia (CLL) is a heterogeneous malignancy displaying varying clinical outcome, where molecular markers today can divide patients into prognostic subgroups. Despite the introduction of new agents for treatment, remissions are usually not sustained in CLL and resistance towards treatment can partly be explained by aberrant apoptosis. The aim of this thesis was to find new drugs for CLL patients resistant to conventional therapy and to analyze genes involved in apoptosis within different prognostic subgroups. In paper I-II, the in vitro activity of substances was investigated using the fluorometric microculture cytotoxicity assay (FMCA). When evaluating rapamycin (paper I), an inhibitor of mTOR, in 97 tumor samples from different entities, CLL was found to be one of the most sensitive tumor types. Combination experiments on patient CLL cells indicated that rapamycin acted synergistically with the CLL drugs vincristine and chlorambucil. An investigation of 20 anti-cancer agents in cells from 40 CLL patients (paper II) revealed that prednisolone and rolipram displayed high activity in poor-prognostic patients, in particular IGHV unmutated CLL. Furthermore, when used in combination these agents were found to produce a synergistic effect. In paper III, the anti-apoptotic BCL2 family member BFL1 was evaluated in 37 CLL cases. Levels of BFL1 were higher in fludarabine-resistant patients compared to fludarabine-sensitive patients. In addition, the high expression of BFL1 inversely correlated to fludarabine-induced apoptosis in CLL cells. A single nucleotide polymorphism in the anti-apoptotic BCL2 gene (-938C>A) has been suggested as a novel poor-prognostic marker in CLL. In paper IV, we investigated this BCL2 polymorphism in 268 CLL patients and correlated genotypes to clinical data. However, no association could be confirmed between this polymorphism and clinical outcome or established prognostic markers. In conclusion, this thesis has shown that rapamycin is a potential drug for treatment in CLL. Furthermore, prednisolone and rolipram were identified as interesting candidates for treatment of poor-prognostic patients. Finally, the anti-apoptotic protein BFL1 may contribute to chemoresistance and hence represents a potential therapeutic target in CLL, whereas from our data, the BCL2 -938C>A polymorphism does not appear to have any prognostic significance.
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| 23. |
- Olsson, A., et al.
(författare)
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Upregulation of bfl-1 is a potential mechanism of chemoresistance in B-cell chronic lymphocytic leukaemia
- 2007
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Ingår i: British Journal of Cancer. - : Springer Science and Business Media LLC. - 0007-0920 .- 1532-1827. ; 97:6, s. 769-777
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Tidskriftsartikel (refereegranskat)abstract
- B-cell chronic lymphocytic leukaemia (B-CLL) is characterised by the progressive accumulation of monoclonal CD5+ B cells. In a previous study, we have analysed the expression profile of apoptosis-regulating genes using a cDNA-based microarray and found overexpression of the antiapoptotic bcl-2 family member, bfl-1, in B-CLL cells with an apoptosis-resistant phenotype. In this study, bfl-1 mRNA levels have been determined by competitive PCR in an extended population of B-CLL patients to characterise its role in disease progression and development of chemoresistance. bfl-1 levels were significantly higher in patients with no response (NR) to last chemotherapy than in patients responding (partial response (PR)) to last chemotherapy (P<0.05) and in patients who had not required treatment (P<0.05). We found no correlation between bfl-1 mRNA levels and disease progression, IGHV mutational status or other clinical parameters. In addition, bfl-1 mRNA levels were inversely correlated with apoptotic response to in vitro fludarabine treatment of B-CLL cells. Specific downregulation of bfl-1 using siRNA induced apoptosis in resistant cells. Our data suggest that bfl-1 contributes to chemoresistance and might be a therapeutic target in B-CLL.
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| 24. |
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| 26. |
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| 27. |
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| 28. |
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| 29. |
- Thunberg, Ulf, et al.
(författare)
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Polymorphism in the P2X7 receptor gene and survival in chronic lymphocytic leukaemia
- 2002
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Ingår i: The Lancet. - 0140-6736 .- 1474-547X. ; 360:9349, s. 1935-1939
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The P2X7 receptor is a ligand-gated cation channel that mediates ATP-induced apoptotic death in haemopoietic and chronic lymphocytic leukaemia (CLL) cells. We aimed to investigate the clinical effect of a single nucleotide polymorphism in the P2X7 receptor gene (1513A-->C) and correlate findings with the immunoglobulin heavy chain variable (V(H)) gene mutation status, a prognostic marker in CLL. METHODS: We investigated tumour DNA in 170 patients with CLL using PCR-RFLP analysis with HhaI restriction enzyme cleavage to screen for the polymorphism in the P2X7 receptor gene. The VH gene mutation status was assessed in 165 patients by PCR amplification and nucleotide sequencing. We correlated the findings of the P2X7 receptor genotype with the V(H) gene mutation data and overall survival and screened for the P2X7 receptor polymorphism in 200 healthy controls. FINDINGS: Of the 170 patients, 35 (21%) were heterozygous and one (1%) homozygous for the 1513C allele; whereas 134 (79%) had the 1513A/A genotype of the P2X7 receptor gene. Overall survival was significantly longer for patients with CLL heterozygous for the 1513C allele than those with the 1513A/A genotype. Median survival for heterozygous patients was 104 months (range 33-467) and 72 months (1-190) for homozygous patients (p=0.009). Of the 165 patients with CLL in whom we assessed the V(H) gene mutation status, the V(H) genes were mutated in 71 (43%) patients and unmutated in 94; 18 (25%) of the 71 patients with mutated genes had 1513C allele compared with 17 (18%) of 94 who had unmutated genes. In patients with mutated VH genes, those with CLL who were 1513C positive had 53 months' longer median survival than did those with the 1513A/A genotype (151 vs 98 months, p=0.011). INTERPRETATION: The P2X7 polymorphism could affect clinical outcome in CLL, especially in patients with mutated V(H) genes. Studies are necessary to elucidate the biological role of the P2X7 polymorphism in CLL in vivo.
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| 30. |
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| 31. |
- Tobin, Gerard, 1971-
(författare)
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Immunoglobulin Gene Analysis in Chronic Lymphocytic Leukemia : Characterization of New Prognostic and Biological Subsets
- 2004
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Recent studies have shown that the somatic mutation status of the immunoglobulin (Ig) VH genes can divide chronic lymphocytic leukemia (CLL) into two prognostic subsets, since cases with mutated VH genes display superior survival compared to unmutated cases. Biased VH gene usage has also been reported in CLL which may reflect antigen selection.We performed VH gene analysis in 265 CLL cases and confirmed the prognostic impact of the VH mutation status. Preferential VH gene usage was also demonstrated in both the mutated and unmutated subset. Interestingly, CLL cases rearranging one particular VH gene, VH3-21, displayed poor outcome despite that two-thirds showed mutated VH genes. Many of the VH3-21 cases expressed λ light chains, rearranged a Vλ2-14 gene, and had homologous complementarity determining region 3s (CDR3s), implying recognition of a common antigen epitope. We believe that the VH3-21 subset comprises an additional CLL entity.To further explore the B-cell receptors in CLL, we analyzed the VH gene rearrangements and, specifically, the heavy chain CDR3 sequences in 346 CLL cases. We identified six new subgroups with similar HCDR3 features and restricted VL gene usage as in the VH3-21-using group. Our data indicate a limited number of antigen recognition sites in these subgroups and give further evidence for antigen selection in the development of CLL.Different cutoffs have been suggested to distinguish mutated CLL in addition to the 2% cutoff. Using three levels of somatic mutations, i.e. <2%, 2-5% and >5%, we divided 323 CLLs into subsets with divergent survival. This division revealed a low-mutated subgroup (2-5%) with inferior outcome that would have been masked using the traditional 2% cutoff. A 1513A/C polymorphism in the P2X7 receptor gene was reported to be more frequent in CLL, but no difference in genotype frequencies was revealed in our 170 CLL cases and 200 controls. However, CLL cases with the 1513AC genotype showed superior survival than 1513AA cases and this was in particular confined to CLL with mutated VH genes. In summary, we could define new prognostic subgroups in CLL using Ig gene rearrangement analysis. This also allowed us to gain insights in the biology and potential role of antigen involvement in the pathogenesis of CLL.
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| 32. |
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| 33. |
- Tobin, Gerard, et al.
(författare)
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Patients with chronic lymphocytic leukemia with mutated VH genes presenting with Binet stage B or C form a subgroup with a poor outcome
- 2005
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Ingår i: Haematologica. - 0390-6078 .- 1592-8721. ; 90:4, s. 465-469
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Tidskriftsartikel (refereegranskat)abstract
- Background and Objectives. The immunoglobulin VH gene mutation status is a strong prognostic indicator in B-cell chronic lymphocytic leukemia (CLL), since unmutated VH genes are correlated with short survival. However, the traditional cut-off level dividing mutated and unmutated cases, i.e. more or less than 2% mutations, has been questioned and other cut-offs have been suggested. We investigated whether an alternative cut-off should be applied and the relation of mutational status to another prognostic marker, Binet staging. Design and Methods. VH gene mutation status was assessed in 332 CLL cases by polymerase chain reaction amplification and nucleotide sequencing and was further correlated with overall survival using different VH mutation cut-offs (1-7%) and Binet stage. Results. After testing different mutation borders, the 2% cut-off remained the best discriminative level for determining prognosis. Interestingly, prognostic stratification was improved by combining the information on VH gene mutation status with that of Binet stage: unmutated cases (all stages, n=151, mutated cases with stage A (n=77), and mutated cases with stage B or C (n=37) had a median survival of 82, 179 and 74 months, respectively. Interpretation and Conclusions. CLL cases displaying mutated VH genes with Binet stage B or C had a survival similar to that of unmutated cases and significantly shorter than that of mutated stage A CLL. Our result reveals clinical heterogeneity within the VH mutated CLL group by inclusion of Binet stage data, a finding which is of importance when considering surrogate marker(s) for VH mutation status. ©2005 Ferrata Storti Foundation.
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| 34. |
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| 35. |
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| 36. |
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| 37. |
- Tobin, Gerard, et al.
(författare)
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Somatically mutated Ig V(H)3-21 genes characterize a new subset of chronic lymphocytic leukemia
- 2002
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Ingår i: Blood. - 0006-4971 .- 1528-0020. ; 99:6, s. 2262-2264
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Tidskriftsartikel (refereegranskat)abstract
- Recent studies on the immunoglobulin variable heavy chain (IgV(H)) genes have revealed that B-cell chronic lymphocytic leukemia (B-CLL) consists of at least 2 clinical entities with either somatically mutated or unmutated V(H) genes. We have analyzed the V(H) gene mutation status and V(H) gene usage in 119 B-CLL cases and correlated them to overall survival. A novel finding was the preferential use of the V(H)3-21 gene in mutated cases, whereas biased V(H)1-69 gene usage was found in unmutated cases as previously reported. Interestingly, the subset of mutated cases using the V(H)3-21 gene displayed distinctive genotypic/phenotypic characteristics with shorter average length of the complementarity determining region 3 and clonal expression of lambda light chains. In addition, this mutated subset showed significantly shorter survival than other mutated cases and a similar clinical course to unmutated cases. We therefore suggest that B-CLL cases with mutated V(H)3-21 genes may constitute an additional entity of B-CLL.
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| 38. |
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| 39. |
- Tobin, Gerard, et al.
(författare)
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Subsets with restricted immunoglobulin gene rearrangement features indicate a role for antigen selection in the development of chronic lymphocytic leukemia.
- 2004
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Ingår i: Blood. - : American Society of Hematology. - 0006-4971 .- 1528-0020. ; 104:9, s. 2879-85
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Tidskriftsartikel (refereegranskat)abstract
- Pseudohypoaldosteronism type I (PHA1) is a condition associated with salt wasting leading to dehydration, hypotension, hyperkalemia, and metabolic acidosis. Sporadic cases and two familial forms, one autosomal dominant and one autosomal recessive form, have been described. The autosomal dominant or sporadic form manifests milder salt wasting that remits with age. Mutations in the gene encoding the mineralocorticoid receptor (MR) have been identified in patients with the autosomal dominant inheritance. However, recent studies suggest that the autosomal dominant and sporadic forms are genetically heterogeneous and that additional genes might be involved. We report on the study of 15 members of a Swedish five-generation family with the autosomal dominant form of PHA1. Interestingly, neuropathy was found in two of five affected individuals. A novel heterozygous nonsense mutation C436X in exon 2 was identified in the index patient by linkage analysis, PCR, and direct sequencing of the MR gene. Analysis of the family demonstrated that the mutation segregated with PHA1 in the family. It is unclear whether the neuropathy is associated with the mutation found. Our results together with previously published data suggest that loss-of-function mutations of the MR gene located at 4q31.1, commonly are associated with the autosomal dominant form of PHA1.
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| 40. |
- Tobin, Gerard
(författare)
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The immunoglobulin genes : Structure and specificity in chronic lymphocytic leukemia
- 2007
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Ingår i: Leukemia and Lymphoma. - : Informa UK Limited. - 1042-8194 .- 1029-2403. ; 48:6, s. 1081-1086
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Forskningsöversikt (refereegranskat)abstract
- The rearrangement of the immunoglobulin genes (IG) provides a large diversity of B-cell receptors conformations and allows the immune system to respond differently to foreign antigens. In chronic lymphocytic leukemia (CLL), there are a restricted number of stereotyped B-cell receptors rearranged by the tumor B-cells between CLL patients. These subsets with stereotyped receptors appear to have clinical implications, for example cases that rearrange the IGHV3-21 gene display poor clinical prognosis. The number of subsets with stereotyped receptors has been reported at a frequency of over 20% of CLL cases; however, the specificities of these receptors are still not clearly defined. Reactivity to epitopes from bacterial antigen, cytoskeleton components such as vimentin, and antigens on viable and apoptotic T-cell have been proposed. The role of antigen in CLL development is currently being more clearly defined with identification of stereotyped receptors, and their antigen specificity and the continued role antigen stimulation plays in CLL disease will be an important question in the future.
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| 41. |
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| 42. |
- Tobin, Gerard, et al.
(författare)
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What is the current evidence for antigen involvement in the development of chronic lymphocytic leukemia?
- 2006
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Ingår i: Hematological Oncology. - : Wiley. - 0278-0232 .- 1099-1069. ; 24:1
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Tidskriftsartikel (refereegranskat)abstract
- For many years it has been evident that B-cell chronic lymphocytic leukemia (CLL) displays preferential usage of individual immunoglobulin (Ig) variable heavy chain (VJapanese sourceH) genes. The VH1-69 gene was the first to be reported overrepresented in a large number of CLL patients, where the VH1-69+ CLL rearrangements showed characteristic molecular features, such as unmutated VH genes, usage of specific diversity/joining gene segments, and a longer than average complementarity determining region (CDR) 3 with certain common amino acid motifs. Also, biased usage of the VH3-07 and VH4-34 genes with specific rearrangement characteristics was reported in CLL. These findings led to the speculation that antigens could be involved during CLL development by triggering proliferation of B-cells with specific B-cell receptors (BCRs) leading to an increased risk of transforming events. Recently, we characterized a subset of CLL utilizing the VH3-21 gene that also displayed peculiar Ig features, e.g. very short and homologous CDR3s, predominant λ expression and preferential Vλ2-14 gene usage. This VH3- 21+ subgroup also had poor prognosis despite the fact that two-thirds of cases carried mutated VH genes. Moreover, we and others have thereafter described further CLL subsets with very similar heavy and light chain gene rearrangement features. These latter findings of subsets expressing restricted BCRs have emphasized the hypothesis that antigens could play a role during the pathogenesis of CLL. Interestingly, recombinant antibodies produced from these restricted subsets showed similar cytoplasmatic reactivity within each group, thus suggesting recognition of a limited number of autoantigens. Further characterization of antigens is now necessary in order to understand their nature and exact role in CLL development.
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| 43. |
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| 44. |
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| 45. |
- Walsh, Sarah H, et al.
(författare)
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Telomere length and correlation with histopathogenesis in B-cell leukemias/lymphomas
- 2007
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Ingår i: European Journal of Haematology. - : Wiley. - 0902-4441 .- 1600-0609. ; 78:4, s. 283-289
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Tidskriftsartikel (refereegranskat)abstract
- Telomere length was recently reported to correlate with cellular origin of B-cell malignancies in relation to the germinal center (GC). In this report, we measured telomere length by quantitative-PCR in 223 B-cell lymphomas/leukemias and correlated results with immunoglobulin (Ig) mutation status and immunostainings for GC/non-GC subtypes of diffuse large B-cell lymphoma (DLBCL). Shortest telomeres were found in Ig-unmutated chronic lymphocytic leukemia (CLL) [median telomere to single copy gene value (T/S) 0.33], differing significantly to Ig-mutated CLL (0.63). Contrary to this, mantle cell lymphomas (MCLs) exhibited similar telomere lengths regardless of Ig mutation status (0.47). Telomere length differed significantly between GC-like (0.73) and non-GC-like DLBCLs (0.43), and follicular lymphomas (FLs) had shorter telomeres (0.53) than GC-DLBCL. Hairy cell leukemias, which display Ig gene intraclonal heterogeneity, had longer telomeres (0.62) than FLs and non-GC-DLBCL, but shorter than GC-DLBCL. We conclude that although DLBCL and CLL subsets can be clearly distinguished, telomere length reflects many parameters and may not simply correlate with GC-related origin.
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| 46. |
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| 47. |
- Åleskog, Anna, et al.
(författare)
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Rapamycin shows anticancer activity in primary chronic lymphocytic leukemia cells in vitro, as single agent and in drug combination
- 2008
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Ingår i: Leukemia and Lymphoma. - : Informa UK Limited. - 1042-8194 .- 1029-2403. ; 49:12, s. 2333-2343
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Tidskriftsartikel (refereegranskat)abstract
- The mammalian target of rapamycin inhibitor rapamycin and its analogues show promising anticancer activity in various experimental tumor models and are presently evaluated in clinical trials. We, here, evaluated the in vitro activity of rapamycin with regard to tumor-type specificity and possible mechanisms of drug resistance in 97 tumor cell samples from patients and in a resistance-based cell line panel, using the fluorometric microculture cytotoxicity assay. Rapamycin was dose-dependently cytotoxic in patient tumor cells and in cell lines. In primary cells, rapamycin was more active in hematological than in solid tumor samples, with chronic lymphocytic leukemia (CLL) and acute lymphocytic leukemia being the most sensitive tumor types. Considerable inter-individual differences in sensitivity were apparent among CLL samples, but no difference was observed between IGHV mutated and unmutated CLL samples, whereas a tendency to lower rapamycin sensitivity was indicated for samples displaying poor-prognostic genomic markers. Combination experiments in CLL cells indicated that rapamycin acted synergistically with vincristine, cisplatin, chlorambucil and taxotere. These results and the clinically-experienced good tolerance to rapamycin analogues encourage clinical studies of rapamycin in CLL treatment as single agent but also in combination with, e.g., vincristine and chlorambucil.
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| 48. |
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