| 1. |
- Elmroth, Kerstin, 1970, et al.
(author)
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Influence of temperature on radiation-induced inhibition of DNA supercoiling
- 1999
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In: Radiat Res. - 0033-7587. ; 152:2, s. 137-43
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Journal article (peer-reviewed)abstract
- The influence of subnormal temperatures (2, 15 and 28 degrees C) on the effects of radiation in MCF-7 cell cultures was studied using the fluorescent (halo) nucleoid assay. Increasing the propidium iodide (PI) concentration (0.5-7.5 microgram/ml PI) resulted in relaxation, i.e. in increasing nucleoid area; higher concentrations up to 50 microgram/ml caused rewinding that resulted in nucleoid contraction. Rewinding was inhibited by X irradiation (2, 4 and 8 Gy) in a dose-dependent way. Incubation at subnormal temperature did not influence the nucleoid area but did reduce radiation-induced inhibition of rewinding after 4 Gy. The low temperature (2 degrees C) during rather than prior to irradiation appeared to protect from radiation-induced inhibition of nucleoid rewinding. Decreased temperature during irradiation may change the conditions so as to reduce DNA- matrix damage induced by radiation.
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| 2. |
- Elmroth, Kerstin, 1970, et al.
(author)
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Radiation and hypothermia: changes in DNA supercoiling in human diploid fibroblasts
- 1999
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In: Anticancer Res. - 0250-7005 .- 1791-7530. ; 19:6B, s. 5307-11
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Journal article (peer-reviewed)abstract
- The influence of hypothermia (2 degrees, 15 degrees and 28 degrees C) upon the effect of X-irradiation on chromatin from human diploid fibroblast cells (AG1518) was studied using the fluorescent halo assay. Rewinding of supercoils was inhibited in a dose-dependent manner when cells were irradiated with 4, 8 or 16 Gy. This inhibition of rewinding was reduced when cells were irradiated at subnormal temperatures compared with cells irradiated at 37 degrees C. One hour's preincubation at low temperature did not influence rewinding. When AG1518 cells were irradiated at 37 degrees C in the presence of the radical scavenger DMSO (0.5 M), the radiation-induced damage was reduced. No additional protection of DMSO in hypothermic cells (2 degrees C) was found, possibly indicating that OH-radical-mediated effects are more temperature dependent. These results are similar to those recently found for the malignant MCF-7 cell line.
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| 3. |
- Gritli Linde, Amel, 1959, et al.
(author)
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Effects of suramin on polyamine metabolism in B16 murine melanoma cells
- 1998
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In: Anticancer Res. - 0250-7005. ; 18:2A, s. 855-62
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Journal article (peer-reviewed)abstract
- Polyamines and their biosynthetic enzymes, such as ornithine decarboxylase (ODC) and S-adenosylmethionine decarboxylase (AdoMetDC), are crucial for normal and neoplastic cell growth and differentiation. Suramin inhibits the growth of several tumor cells by affecting various intracellular targets, but its effects on polyamines are not known. In this study, the effects of suramin on some parameters of polyamine metabolism in B16 melanoma cells were investigated in vitro. Suramin increased cellular ODC activity and ODC mRNA levels, whereas the drug was directly inhibitory to the enzyme. AdoMetDC was not affected. Cellular putrescine levels were enhanced by suramin, whereas spermidine and spermine pools were unaltered. Cells cultured in the presence of suramin showed decreased cellular polyamine transport, but no direct inhibitory effect on the polyamine transporter could be found. Fluorescence spectroscopy demonstrated a direct interaction between suramin and spermine. It may be concluded that suramin affects polyamine metabolism, and that its effects in some respects are opposite to those of alpha-difluoromethylomithine (DFMO), a specific inhibitor of ODC.
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| 4. |
- Gritli Linde, Amel, 1959, et al.
(author)
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Opposing effects of suramin and DL-alpha-difluoromethylornithine on polyamine metabolism contribute to a synergistic action on B16 melanoma cell growth in vitro
- 1998
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In: Anticancer Res. - 0250-7005. ; 18:2A, s. 863-70
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Journal article (peer-reviewed)abstract
- Polyamines are crucial for normal and neoplastic cell growth. Treatment with the polyanionic drug suramin has pronounced antigrowth activity in several tumor cell lines, but its clinical use has been hampered by its toxicity. We have earlier shown that suramin affects cellular polyamine metabolism and transport, and that these effects were, in some respects, opposite to those of alpha-difluoromethylomithine (DFMO), a specific inhibitor to ornithine decarboxylase, a key metabolic enzyme for polyamines. DFMO has been used in anticancer trials, although with limited success. Combinations of suramin and DFMO were, hence, evaluated in vitro and were found to strongly inhibit B16 melanoma cell proliferation. DFMO alone induced melanoma cell differentiation, and suramin used in combination with DFMO did not abrogate this DFMO-induced differentiation. Synergy analysis demonstrated a pronounced growth-inhibitory synergism between suramin and DFMO. The results suggest that the efficacy of combinations of DFMO with suramin or its analogues should be further explored, especially in cells requiring high levels of polyamines for their growth.
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| 5. |
- Hultborn, Ragnar, 1946, et al.
(author)
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Efficacy of pamidronate in breast cancer with bone metastases: a randomized, double-blind placebo-controlled multicenter study
- 1999
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In: Anticancer Res. - 0250-7005. ; 19:4C, s. 3383-92
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Journal article (peer-reviewed)abstract
- PURPOSE: To evaluate the efficacy of pamidronate 60 mg i.v. q 4 weeks in women with advanced breast cancer with skeletal metastases. PATIENTS AND METHODS: 404 woman with skeletal metastases from breast cancer in Sweden and Norway were included in a randomized, placebo-controlled, multicenter study. Except for the study medication, other palliative treatment was chosen at the discretion of the physician. Skeletal related events, i.e. increased pain, treatment of hypercalcemia, pathologic fractures of long bones or pelvis, paralyses due to vertebral compression, palliative radiotherapy for skeletal metastases, surgery on bone and change of antitumor therapy were recorded every third month as well as a self-estimated pain-score using visual Analog Scales and analgesic consumption. RESULTS: There was a significantly increased time to progression of pain (p < 0.01), to hypercalcemic events (p < 0.05) as well as for the cumulative number of skeletal related events (p < 0.01) in favor for the pamidronate group. No statistically significant reduction of pathologic fractures of long bones or pelvis, or pareses due to vertebral compression occurred. No statistically significant differences were found for the need of radiotherapy and surgery on bone. The pamidronate group faired better regarding performance status (p < 0.05). There was a statistically not significant lower consumption of opioid analgesics in the pamidronate group (p = 0.14). CONCLUSION: Pamidronate 60 mg i.v. q 4 weeks reduces skeletal events and improves the quality of life in women with bone metastases from breast cancer.
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| 6. |
- Hultborn, Ragnar, 1946, et al.
(author)
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Prevalence of Klinefelter's syndrome in male breast cancer patients
- 1997
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In: Anticancer Res. - 0250-7005. ; 17:6D, s. 4293-7
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Journal article (peer-reviewed)abstract
- Klinefelter's syndrome (KS, XXY) as a risk factor for developing breast cancer was evaluated in a retrospective study of 93 unselected male breast cancer patients from the Healthcare region of Western Sweden. Archival normal material from lymph nodes or skin and subcutaneous tissue was examined using the FISH (fluorescence in situ hybridisation)-technique. The best yield of intact nuclei was obtained from lymph node tissue. The prevalence rate of KS in males with breast cancer was found to be 7.5 per cent, a much higher rate than previously reported (approximately 3 per cent). Methodological differences are suggested to cause the increased prevalence rate. Based on our finding and on the prevalence of KS in the normal population as well as on the incidence of MBC, a 50-fold increased risk of developing breast cancer in males with KS relative to normal males was found. The same median age at diagnosis, 72 years, was established for both groups of patients. No differences in survival were seen.
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| 7. |
- Landys, Karl, et al.
(author)
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Prognostic value of bone marrow biopsy in operable breast cancer patients at the time of initial diagnosis: Results of a 20-year median follow-up
- 1998
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In: Breast Cancer Res Treat. - 0167-6806. ; 49:1, s. 27-33
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Journal article (peer-reviewed)abstract
- From May 1975 until May 1980,128 operable breast cancer patients, clinical stage I-II, had a core bone marrow biopsy (BMB) from the posterior iliac crest as a part of the routine diagnostic work-up at the time of initial diagnosis. The mean age of the patients was 56 years, range 26-93. In a previous study on this material, 10 patients (7.8 per cent) were positive for tumor cells and 118 negative by conventional histopathology of BMB [1]. In 1996 we reexamined all BMB separately at two laboratories, using monoclonal antibodies against cytokeratins AE1-AE3, KL1, CAM 5-2 (DOP), and DC10, BA17 (MCI). The number of extrinsic cells in the bone marrow was graded positive for micrometastases when > or = 5 cells or suspicious when 1-4 cells per approximately 2 x 10(6) bone marrow cells were found, using high power field magnification. Micrometastases were detected in 17 patients (13.3 per cent) and another 8 patients were classified as suspicious. The presence of micrometastases was correlated to the axillary lymph node stage and primary tumor location. Median follow-up was 20 years. All 17 micrometastatic patients relapsed and died within 6 years of disease progression with evident osseous metastases. There was one disease-free survivor of the 8 patients with suspicious BMB after 17 years of follow-up. The median overall survival was significantly shorter in tumor-cell positive patients, being 1.9 years compared to 11.7 years in the BMB negative and BMB suspicious groups (p < 0.0001). Immunohistochemical analysis of core BMB taken postoperatively may be useful in predicting the prognosis in patients with breast cancer clinical stage I-II.
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| 8. |
- Mansson, J., et al.
(author)
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Symptom pattern and diagnostic work-up of malignancy at first symptom presentation as related to level of care. A retrospective study from the primary health care centre area of Kungsbacka, Sweden
- 1999
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In: Neoplasma. - 0028-2685. ; 46:2, s. 93-9
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Journal article (peer-reviewed)abstract
- This retrospective study was aimed to characterize the diagnostic process of cancer with respect to level of care, initial symptoms, and diagnostic procedures. It was based on analysis of medical records of all subjects with colorectal, pulmonary, breast or prostate cancer, reported to the Swedish Cancer Registry during defined periods of time in the community of Kungsbacka with about 46,500 inhabitants. Initial symptoms, diagnostic procedures, outcome of diagnostic procedures, level of care, and doctor's delay were analyzed. Most patients (62-73% for the different cancers studied) first visited a general practitioner for the symptoms which lead to the diagnosis of cancer. The most common initial symptom for colorectal cancer was defecation abnormality, for breast cancer a palpable mass in the breast, for pulmonary cancer cough, and for prostate cancer symptoms of prostatism. There was no difference in doctor's delay between general practitioners and other physicians. Nonspecific blood laboratory tests made little contribution to the diagnosis of cancer. The results indicate that most cancers of the types studied are diagnosed in primary health care and that it is possible to improve the identification of the few malignant cases among the "noise" of benign diseases, both with respect to accuracy and cost-effectiveness. It seems that focused investigations such as fecal occult blood tests and rectoscopy should be more frequently used in patients with gastrointestinal symptoms.
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| 9. |
- Ottosson, Susanne, et al.
(author)
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Acute hematologic feasibility of G-CSF supported dose-escalated FEC therapy as adjuvant treatment after breast cancer surgery
- 1999
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In: Anticancer Res. - 0250-7005. ; 19:5C, s. 4429-34
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Journal article (peer-reviewed)abstract
- A study of the feasibility of gradually increased epirubicin and cyclophosphamide dosage in an FEC regimen with G-CSF (granulocyte colony stimulating factor) support in 18 high-risk breast cancer patients as adjuvant treatment was carried out. The FEC regimen was initiated with 5-fluorouracil 600 mg/m2, epirubicin 75 mg/m2 and cyclophosphamide 900 mg/m2 together with G-CSF 5 micrograms/kg subcutaneously on days 2-15 q 3 weeks for nine cycles, increasing individually through four dose levels to a maximum of 5-FU 600 mg/m2 (not escalated), epirubicin 120 mg/m2 and cyclophosphamide 1800 mg/m2. Transient cytopenias were regularly observed without major clinical complications. Rapid recovery and a biphasic overshoot of granulocytes required individualization of G-CSF support. During the 6-month treatment period, a general decline in granulocytes, platelets and haemoglobin was observed, resulting in maximal dose intensity in the middle of the treatment period. Compared to a conventional FEC regimen (5-Fluorouracil 600 mg/m2, Epirubicin 60 mg/m2, Cyclophosphamide 600 mg/m2 q 3 w) without dose reductions, it was feasible to increase the dose of epirubicin by more than 50 per cent with an increased dose intensity between 25 and 70 per cent. The dose of cyclophosphamide was increased by more than 100 per cent. All patients suffered from complete alopecia and moderate nausea, but there was no acute cardiac or severe mucosal toxicity. It was concluded that intensified, G-CSF supported FEC therapy can be safely administered in an outpatient setting, provided the patients are thoroughly informed and adequately monitored. High-risk patients are enrolled in a study comparing the described regimen and a myeloablative regimen including peripheral stem-cell support. Breast cancer seems to respond to chemotherapy in a dose dependent manner, suggesting the use of dose intensified regimens (1,8,9,11). This approach is currently under investigation in studies comparing standard regimens with myelo-ablative regimens in high-risk primary breast cancer (3,10). In a Scandinavian multicenter study (2), two high dose regimens, G-CSF supported dose-escalated FEC and myeloablative cyclophosphamide-thiotepacarboplatin with peripheral stem cell support, are compared as adjuvant therapy in operable high-risk breast cancer. This phase I study was performed to assess the feasibility and achievable dose intensity of an individually dose-escalated FEC regimen not in previous use.
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| 10. |
- Palm, Stig, 1964, et al.
(author)
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Effects of the alpha-particle emitter At-211 and low-dose-rate gamma-radiation on the human cell line Colo-205 as studied with a growth assay
- 1998
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In: Anticancer Res. - 0250-7005. ; 18:3A, s. 1671-6
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Journal article (peer-reviewed)abstract
- BACKGROUND: The aim of this study was to investigate the biological effect of the alpha-particle-emitting isotope astatine-211 on the human cell line Colo-205 and to compare it with that of low-dose-rate gamma-radiation. MATERIALS AND METHODS: Plastic (PMMA) rotating phantoms were constructed, allowing precise dosimetry on a cellular level for both types of radiation. Growth assays using 96-well plates were used to estimate apparent cell survival for the two types of radiation. From this, the relative biological effect (RBE) could be estimated. RESULTS: Irradiation of the cells with 211At resulted in an RBE of 25.1 +/- 6.7 at 37% survival, and 17.3 +/- 2.5 at 10% survival, when compared with low-dose-rate gamma-irradiation. The absorbed dose at 37% survival, 0.12 Gy, corresponds to 2.2 traversals of alpha-particles through the cell nuclei. For cells irradiated with gamma-radiation (1 and 2 Gy), an apparent cell survival above unity was observed up to 50 hours post-irradiation, indicating a possible radiation hormesis effect. CONCLUSIONS: The RBE of 211At found in this growth-assay study was significantly higher than previously presented values. The difference might be due to the use of low-dose-rate gamma-radiation as reference. The RBE presented here could prove valuable when evaluating 211At-labelled compounds for radiotherapy.
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| 11. |
- Yang, Y. Y., et al.
(author)
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Growth and clonogenic assays compared for irradiated MCF-7 and Colo-205 cell lines
- 1998
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In: Anticancer Res. - 0250-7005. ; 18:1A, s. 53-9
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Journal article (peer-reviewed)abstract
- Clonogenic assays have been the golden standard for the assessment of cytotoxic injury from irradiation or drugs. Since such assays are time consuming, growth assays, often with automatic quantifying equipment, are frequently used. Since these procedures do not immediately reflect loss of clonogenic capacity, it was considered important to validate the two procedures using gamma-irradiation (0, 2 and 4 Gy) of two human cell lines (MCF-7 and Colo-205). The cells were growing exponentially in 96-well plates and crystal violet staining resulted in optical densities proportional to cell number. The homogeneity of optical densities within the plates was optimal if the wells to be measured were surrounded by liquid-containing ones. The slopes of the exponential growth curves were decreased upon irradiation. An "apparent cell survival", the mean of the three lowest ratios between irradiated and control cells, was defined. It was compared with the SF2 and SF4 as found in parallel Courtenay-Mills assays. In this work we found a modest underestimation of cell survival using the growth assay, ranging from 0 to 17 per cent in absolute terms.
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