1. |
- Andersson, Ulrika, et al.
(author)
-
MNS16A minisatellite genotypes in relation to risk of glioma and meningioma and to glioblastoma outcome.
- 2009
-
In: International journal of cancer. Journal international du cancer. - : Wiley. - 1097-0215 .- 0020-7136. ; 125:4, s. 968-972
-
Journal article (peer-reviewed)abstract
- The human telomerase reverse transcriptase (hTERT) gene is upregulated in a majority of malignant tumours. A variable tandem repeat, MNS16A, has been reported to be of functional significance for hTERT expression. Published data on the clinical relevance of MNS16A variants in brain tumours have been contradictory. The present population-based study in the Nordic countries and the United Kingdom evaluated brain-tumour risk and survival in relation to MNS16A minisatellite variants in 648 glioma cases, 473 meningioma cases and 1,359 age, sex and geographically matched controls. By PCR-based genotyping all study subjects with fragments of 240 or 271 bp were judged as having short (S) alleles and subjects with 299 or 331 bp fragments as having long (L) alleles. Relative risk of glioma or meningioma was estimated with logistic regression adjusting for age, sex and country. Overall survival was analysed using Kaplan-Meier estimates and equality of survival distributions using the log-rank test and Cox proportional hazard ratios. The MNS16A genotype was not associated with risk of occurrence of glioma, glioblastoma (GBM) or meningioma. For GBM there were median survivals of 15.3, 11.0 and 10.7 months for the LL, LS and SS genotypes, respectively; the hazard ratio for having the LS genotype compared with the LL was significantly increased HR 2.44 (1.56-3.82) and having the SS genotype versus the LL was nonsignificantly increased HR 1.46 (0.81-2.61). When comparing the LL versus having one of the potentially functional variants LS and SS, the HR was 2.10 (1.41-3.1). However, functionality was not supported as there was no trend towards increasing HR with number of S alleles. Collected data from our and previous studies regarding both risk and survival for the MNS16A genotypes are contradictory and warrant further investigations.
|
|
2. |
- Brohede, Ulrika, et al.
(author)
-
Multifunctional implant coatings providing possibilities for fast antibiotics loading with subsequent slow release
- 2009
-
In: Journal of materials science. Materials in medicine. - : Springer Science and Business Media LLC. - 0957-4530 .- 1573-4838. ; 20:9, s. 1859-1867
-
Journal article (peer-reviewed)abstract
- The possibility to fast-load biomimetic hydroxyapatite coatings on surgical implant with the antibiotics Amoxicillin, Gentamicin sulfate, Tobramycin and Cephalothin has been investigated in order to develop a multifunctional implant device offering sustained local anti-bacterial treatment and giving the surgeon the possibility to choose which antibiotics to incorporate in the implant at the site of surgery. Physical vapor deposition was used to coat titanium surfaces with an adhesion enhancing gradient layer of titanium oxide having an amorphous oxygen poor composition at the interface and a crystalline bioactive anatase TiO2 composition at the surface. Hydroxyapatite (HA) was biomimetically grown on the bioactive TiO2 to serve as a combined bone in-growth promoter and drug delivery vehicle. The coating was characterized using scanning and transmission electron microscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The antibiotics were loaded into the HA coatings via soaking and the subsequent release and antibacterial effect were analyzed using UV spectroscopy and examination of inhibition zones in a Staphylococcus aureus containing agar. It was found that a short drug loading time of 15 min ensured antibacterial effects after 24 h for all antibiotics under study. It was further found that the release processes of Cephalothin and Amoxicillin consisted of an initial rapid drug release that varied unpredictably in amount followed by a reproducible and sustained release process with a release rate independent of the drug loading times under study. Thus, implants that have been fast-loaded with drugs could be stored for ~10 min in a simulated body fluid after loading to ensure reproducibility in the subsequent release process. Calculated release rates and measurements of drug amounts remaining in the samples after 22 h of release indicated that a therapeutically relevant dose could be achieved close to the implant surface for about 2 days. Concluding, the present study provides an outline for the development of a fast-loading slow-release surgical implant kit where the implant and the drug are separated when delivered to the surgeon, thus constituting a flexible solution for the surgeon by offering the choice of quick addition of antibiotics to the implant coating based on the patient need.
|
|
3. |
- Nordfjäll, Katarina, et al.
(author)
-
The individual blood cell telomere attrition rate is telomere length dependent.
- 2009
-
In: PLoS genetics. - : Public Library of Science. - 1553-7404. ; 5:2, s. e1000375-
-
Journal article (peer-reviewed)abstract
- Age-associated telomere shortening is a well documented feature of peripheral blood cells in human population studies, but it is not known to what extent these data can be transferred to the individual level. Telomere length (TL) in two blood samples taken at approximately 10 years interval from 959 individuals was investigated using real-time PCR. TL was also measured in 13 families from a multigenerational cohort. As expected, we found an age-related decline in TL over time (r = -0.164, P<0.001, n = 959). However, approximately one-third of the individuals exhibited a stable or increased TL over a decade. The individual telomere attrition rate was inversely correlated with initial TL at a highly significant level (r = -0.752, P<0.001), indicating that the attrition rate was most pronounced in individuals with long telomeres at baseline. In accordance, the age-associated telomere attrition rate was more prominent in families with members displaying longer telomeres at a young age (r = -0.691, P<0.001). Abnormal blood TL has been reported at diagnosis of various malignancies, but in the present study there was no association between individual telomere attrition rate or prediagnostic TL and later tumor development. The collected data strongly suggest a TL maintenance mechanism acting in vivo, providing protection of short telomeres as previously demonstrated in vitro. Our findings might challenge the hypothesis that individual TL can predict possible life span or later tumor development.
|
|
4. |
- Norén-Nyström, Ulrika, et al.
(author)
-
Bone marrow fibrosis in childhood acute lymphoblastic leukemia correlates to biological factors, treatment response and outcome
- 2008
-
In: Leukemia. - Baltimore : Williams & Wilkins. - 0887-6924 .- 1476-5551. ; 22:3, s. 504-510
-
Journal article (peer-reviewed)abstract
- We retrospectively evaluated reticulin fiber density (RFD) in 166 diagnostic bone marrow (BM) biopsies and 62 biopsies obtained at treatment day 29 from children with acute lymphoblastic leukemia (ALL). Patients with B-cell precursor (BCP)-ALL showed higher RFD as compared to patients with T-cell ALL (P<0.001). RFD correlated negatively with white blood cell count (P=0.008) in BCP-ALL patients. Patients with high-hyperdiploid ALL (51-61 chromosomes), no high-risk criteria and low RFD showed a favorable outcome when compared to similar patients with high RFD (P=0.002). In BCP-ALL patients, RFD at diagnosis correlated to the levels of minimal residual disease (MRD) analyzed by flow cytometry on treatment day 29 (P=0.001). Accordingly, patients with MRD > or = 10(-4) presented higher RFD at diagnosis compared to patients with MRD < 10(-4) (P=0.003). BCP-ALL patients with low RFD at diagnosis and a rapid reduction of RFD on day 29 had a favorable outcome compared to patients with the same baseline RFD level at diagnosis but a slow RFD reduction (P=0.041). To our knowledge, these findings are novel and may indicate BM fibrosis as a new valuable prognostic marker in childhood ALL. Expanded use of BM biopsy both at diagnosis and during follow-up is suggested.
|
|
5. |
|
|
6. |
- Norén Nyström, Ulrika, 1965-
(author)
-
Vascular density and bone marrow fibrosis in childhood acute lymphoblastic leukemia
- 2008
-
Doctoral thesis (other academic/artistic)abstract
- Background: In childhood acute lymphoblastic leukemia (ALL), the cure rate has now reached 80% in the western world. Even so, 15¬–20% will die from the disease or treatment-related causes, among them children who did not present any known unfavorable features at diagnosis. Treatment of childhood ALL is risk-adapted, meaning that certain factors that are related to the child or the leukemic blasts stratifies to more or less intensive treatment. In this thesis, characteristics of the bone marrow (BM) stroma, reflecting the interaction between the leukemic cells and their microenvironment, were evaluated. The aims were to investigate these factors in relation to other known data in order to further understand the biology of leukemia, and to suggest additional risk factors that would further improve decision making for the treatment of individual children diagnosed with ALL. Methods: We retrospectively investigated microvessel density (MVD), blast-congested vessel fraction (BCVF), and degree of fibrosis – reticulin fiber density (RFD) – in sections from diagnostic BM biopsies from children diagnosed in Umeå, Uppsala, and Stockholm. RFD was also studied in BM sections from treatment day 29. Results: RFD had prognostic impact in patients with high-hyperdiploid (HeH) leukemia. Moreover, rapid reduction of RFD during induction treatment was associated with a favorable prognosis compared to slow reduction, in B-cell precursor (BCP) ALL patients. There was also a correlation between RFD at diagnosis and minimal residual disease (MRD) measured by flow cytometry on treatment day 29 in BCP patients. BCP patients with high RFD and high MVD had an unfavorable outcome compared to all other BCP patients. In addition, MVD and RFD were both associated with immunophenotype, and MVD with cytogenetic aberrations. There was a correlation between MVD and WBC count in BCP high-risk patients. There was also a strong correlation between BCVF and WBC count in all BCP patients, but not between BCVF and MVD or RFD. There was a negative correlation between MVD and in vitro cellular resistance to several drugs in BCP patients. A drug-resistance score combining the drugs most strongly correlated to MVD – cytarabine, doxorubicin, and dexametasone (ADD score) – identified the prognostic potential of ADD score in HeH patients with no unfavorable features. Conclusions: Taken together, these studies indicate that stroma factors in leukemia are related to both phenotypic and genotypic features of acute leukemia. Stroma factors also seem to influence the response to induction treatment, in vitro drug resistance, and outcome in certain subgroups of childhood ALL patients. The results emphasize the importance of BM stroma in leukemia and the need for greater use of BM biopsy at diagnosis.
|
|
7. |
- Norén-Nyström, Ulrika, et al.
(author)
-
Vascular density in childhood acute lymphoblastic leukaemia correlates to biological factors and outcome
- 2009
-
In: British Journal of Haematology. - : Wiley. - 0007-1048 .- 1365-2141. ; 146:5, s. 521-530
-
Journal article (peer-reviewed)abstract
- The issue of angiogenesis and its clinical relevance in childhood acute lymphoblastic leukaemia (ALL) is controversial. In the present study, microvessel density (MVD), analysed in 185 diagnostic bone marrow biopsies, was higher in T-cell ALL compared to B-cell precursor (BCP)-ALL (P = 0.013). In the BCP group, cases with t(12;21) were characterized by a low MVD while patients with high-hyperdiploid leukaemia (HeH, 51-61 chromosomes) showed a high MVD compared to other BCP patients (P = 0.001 and 0.002 respectively). There was a correlation between MVD and white blood cell (WBC) count in high-risk BCP patients (P = 0.021). In addition, BCP patients with a high marrow reticulin fibre density and high MVD had an unfavourable outcome compared to the other BCP patients (P = 0.002). The fraction of vessels in which lumina were filled with blasts (blast congested vessel fraction) correlated strongly with WBC count (P < 0.001). These findings indicate that the angiogenic process interacts with other stroma-factors, such as reticulin fibre density, in its effect on outcome, and is coupled to both the ALL genotype and phenotype. One possible implication is that different subtypes of childhood ALL may respond differently to anti-angiogenic drugs as a supplement in first-line treatment.
|
|
8. |
- Sonestedt, Emily, et al.
(author)
-
Fat and carbohydrate intake modify the association between genetic variation in the FTO genotype and obesity.
- 2009
-
In: The American journal of clinical nutrition. - : Elsevier BV. - 1938-3207 .- 0002-9165. ; 90, s. 1418-1425
-
Journal article (peer-reviewed)abstract
- BACKGROUND: The fat mass and obesity-associated gene (FTO) has been shown to be associated with obesity and to influence appetite regulation. OBJECTIVE: The aim was to examine whether dietary factors (macronutrient and fiber intakes) and leisure-time physical activity modify the association between genetic variation in FTO and body mass index (BMI; in kg/m(2)). DESIGN: A cross-sectional study examined 4839 subjects in the population-based Malmö Diet and Cancer study with dietary data (from a modified diet history method) and information on the genetic variant FTO (rs9939609). Direct anthropometric measures were made, and leisure-time physical activity was determined from the duration participants spent on 18 different physical activities. RESULTS: Significant interactions between energy-adjusted fat intake and FTO genotype (P = 0.04) and between carbohydrate intake and FTO genotype (P = 0.001) on BMI were observed. The observed increase in BMI across FTO genotypes was restricted to those who reported a high-fat diet, with a mean BMI of 25.3 (95% CI: 24.9, 25.6) among TT carriers and of 26.3 (95% CI: 25.8, 26.8) among AA carriers (P = 0.0001). The FTO variant was not associated with a higher BMI among subjects with lower fat intakes (BMI = 25.7 and 25.9 in TT carriers and AA carriers, respectively; P = 0.42). Among individuals with a low-carbohydrate intake, we observed a mean BMI of 25.4 for TT carriers and of 26.8 for AA carriers. The increase in BMI across genotypes was mainly restricted to individuals who reported low leisure-time physical activity (P for trend = 0.004, P for interaction = 0.05). CONCLUSION: Our results indicate that high-fat diets and low physical activity levels may accentuate the susceptibility to obesity by the FTO variant.
|
|
9. |
- Svenson, Ulrika, et al.
(author)
-
Breast cancer survival is associated with telomere length in peripheral blood cells
- 2008
-
In: Cancer Research. - 0008-5472 .- 1538-7445. ; 68:10, s. 3618-3623
-
Journal article (peer-reviewed)abstract
- Telomeres are essential for maintaining chromosomal stability. Previous studies have indicated that individuals with shorter blood telomeres may be at higher risk of developing various types of cancer, such as in lung, bladder, and kidney. We have analyzed relative telomere length (RTL) of peripheral blood cells in relation to breast cancer incidence and prognosis. The study included 265 newly diagnosed breast cancer patients and 446 female controls. RTL was measured by real-time PCR, and our results show that the patient group displayed significantly longer telomeres compared with controls (P < 0.001). Age-adjusted odds ratios (OR) for breast cancer risk increased with increasing telomere length, with a maximal OR of 5.17 [95% confidence interval (95% CI), 3.09-8.64] for the quartile with the longest telomeres. Furthermore, RTL carried prognostic information for patients with advanced disease. Node positive (N+) patients with short telomeres (16 mm (median tumor diameter), short telomeres were associated with a significantly better outcome than longer telomeres (P = 0.006). Cox regression analysis showed that long RTL was a significant independent negative prognostic factor (hazards ratio, 2.92; 95% CI, 1.33-6.39; P = 0.007). Our results indicate that blood RTL may serve as a prognostic indicator in breast cancer patients with advanced disease.
|
|
10. |
- Svenson, Ulrika, et al.
(author)
-
Telomere length as a biological marker in malignancy.
- 2009
-
In: Biochimica et Biophysica Acta. - : Elsevier BV. - 0006-3002 .- 1878-2434. ; 1792:4, s. 317-323
-
Journal article (peer-reviewed)abstract
- Telomere maintenance is important for tumor cell growth and survival. Telomere length (TL) is determined by the balance between positive and negative factors impacting telomere homeostasis. In the last decade, TL has emerged as a promising clinical marker for risk and prognosis prediction in patients with malignant disorders. Tumor TL, as well as TL in healthy tissues such as peripheral blood, may carry valuable information for future treatment strategies. Here we discuss the present status of TL as a biological marker in cancer patients.
|
|