| 51. |
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| 52. |
- Borg, Åke, et al.
(författare)
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c-myc amplification is an independent prognostic factor in postmenopausal breast cancer
- 1992
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Ingår i: International Journal of Cancer. - : Wiley. - 0020-7136 .- 1097-0215. ; 51:5, s. 687-691
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Tidskriftsartikel (refereegranskat)abstract
- The c-myc proto-oncogene was analyzed in 311 cases of primary breast cancer, in 8% of which it was found to be amplified, usually at moderately increased copy number (2-5 copies). The adjacent pvt gene was co-amplified with c-myc in all tumors analyzed. C-myc amplification was significantly correlated to a high S-phase fraction and to amplification of the c-erbB-2 proto-oncogene. Weak relationships were found between c-myc amplification and the presence of lymph-node metastasis, advanced stage, DNA non-diploidy and premenopausal status, but not tumor size, estrogen receptor or progesterone receptor status, or int-2 amplification. C-myc amplification, and especially a high gene copy number (greater than 5 copies), was significantly related to early recurrence and death in breast cancer, a relationship seen in both the lymph-node-negative and node-positive subcategories. A particularly strong correlation with poor clinical outcome was seen in postmenopausal patients (p greater than 0.0005), an association which persisted in multivariate survival analysis. We conclude that the activation of c-myc is indeed associated with rapidly growing and progressive breast cancer. Gene amplification, on the other hand, is relatively infrequent and occurs mostly at low copy number, implying that tumors are heterogeneous with respect to cell clones harboring c-myc amplification. An immunohistochemical assessment would more accurately illustrate the importance of c-myc activation in human breast cancer. However, the obvious instability of the c-myc transcript and translate suggests that c-myc is not a suitable prognostic marker for routine purposes.
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| 53. |
- Borg, Åke, et al.
(författare)
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Chromosome I alterations in breast cancer : Allelic loss on Ip and Iq Is related to lymphogenic metastases and poor prognosis
- 1992
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Ingår i: Genes, Chromosomes and Cancer. - : Wiley. - 1045-2257 .- 1098-2264. ; 5:4, s. 311-320
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Tidskriftsartikel (refereegranskat)abstract
- The development of human breast cancer is characterized by a variety of genetic alterations, and cytogenetic analyses have documented the consistent involvement of both arms of chromosome I. In the present study, molecular markers detecting restriction fragment length polymorphisms were used in pairwise screening of normal and tumor DNA to determine the frequency of allelic imbalance in breast tumors. Loss of heterozygosity (LOH) in the polymorphic epithelial mucin (PEM or MUCI) gene at 1q21 was found in 16% of 89 informative (constitutionally heterozygous) cases, whereas gain in intensity of one allelic band was more frequent (37%), a total of 47% of cases manifesting either allelic loss or gain. Three additional tumors manifested a structural alteration. Allelic loss or gain in the PEM gene was not associated with other prognostic factors, e.g., tumor size, lymph node status, steroid receptors, DNA ploidy, S phase fraction, protooncogene amplification, histological type, or patient age. However, LOH in the PEM gene was significantly correlated with early disease recurrence (P = 0.006). LOH on 1p was found in 27% of 117 informative cases, using probes for either DIS57 or DIZ2 located at 1p33‐p35 and 1p36, respectively. Somatic allelic imbalance on 1p and 1q seemed to be independent events and not the effect of loss of a whole chromosome 1. LOH on 1 p was significantly correlated to the presence of lymph node metastasis, to larger tumor size, and to DNA nondiploidy, but no correlation was found to disease outcome at this limited duration of follow‐up (median 29 months). ©1992 Wiley‐Liss, Inc.
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| 54. |
- Borg, Åke, et al.
(författare)
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ERBB2 amplification in breast cancer with a high rate of proliferation
- 1991
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Ingår i: Oncogene. - 1476-5594. ; 6:1, s. 137-143
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Tidskriftsartikel (refereegranskat)abstract
- The ERBB2 proto-oncogene was studied in 539 invasive primary breast tumors and was found amplified (2- greater than 30 copies) in 19%. Amplification was correlated to most known risk factors, including; large tumor size, lymph node positivity and many tumor involved nodes, advanced stage, low patient age (less than 40 years), non-diploidy and hypertetraploidy, and most significantly (P less than 0.00001) to the absence of steroid receptors and to a high rate of proliferation (flow cytometric determined S phase fraction). ERBB2 amplification was strongly associated (P less than 0.0001) with early recurrence and death in breast cancer among node-positive patients. This connection did not, however, remain in multivariate analyses. No correlations to clinical outcome were seen among node-negative patients. Similarly, non-diploid, but not diploid, amplified tumors were particularly aggressive. Furthermore, ERBB2 amplification was associated with a high rate of proliferation and poor prognosis in steroid receptor positive, but not receptor negative tumors. In progesterone receptor positive breast cancer, amplification was an independent and with node status equally powerful (P less than 0.0001) predictor of poor survival. It is concluded that ERBB2 activity is related to an increased tumor growth rate but not directly to metastasizing ability. Its clinical relevance as a prognostic factor may be in selecting a high risk subgroup of breast cancer, in general considered as being of good prognosis.
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| 55. |
- Borg, Åke, et al.
(författare)
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ERBB2 amplification is associated with tamoxifen resistance in steroid-receptor positive breast cancer
- 1994
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Ingår i: Cancer Letters. - : Elsevier BV. - 1872-7980 .- 0304-3835. ; 81:2, s. 137-144
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Tidskriftsartikel (refereegranskat)abstract
- Amplification and overexpression of the ERBB2 (HER-2/neu) oncogene has been implicated as contributing to the development of human breast cancer, and as a predictor of poor survival. In the present non-randomized study of 871 primary invasive breast tumours, ERBB2 activation was significantly correlated to a shorter disease-free and overall survival in the subgroup of patients receiving adjuvant tamoxifen therapy, but not in the untreated group. Further subcategorization demonstrated the relationship to poor prognosis to be confined to lymph node positive and steroid receptor-positive tumours. We suggest that steroid receptor and ERBB2-positive breast tumours are resistant to tamoxifen therapy and, supported by experimental evidence showing an oestrogen receptor dependent up-regulation of ERBB2 expression upon tamoxifen administration, possibly even growth stimulated by the drug.
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| 56. |
- Brandt, L., et al.
(författare)
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Mitotic activity and survival in advanced non-Hodgkin's lymphoma of unfavourable histology
- 1990
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Ingår i: European Journal of Cancer and Clinical Oncology. - 0277-5379. ; 26:3, s. 227-230
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Tidskriftsartikel (refereegranskat)abstract
- The number of mitoses per high power field (mitotic index, MI) was assessed in 2 νm sections of lymph node biopsies from 58 adults with non-Hodgkin's lymphoma. All had diffuse nodal lymphomas of unfavourable histology and stage II-IV disease. The patients were treated with chemotherapy and followed for a minimum of 3 years or until death. None out of 29 patients with a MI ≥ 3.0 survived for 3 years after diagnosis whereas 13 out of 29 other patients with MI <3.0 became long-term survivors (P = 0.00002). Differences in age, sex or clinical stage between short- and long-term survivors were negligible. The initial chemotherapy regimens were not more intense for the long-term survivors. Twenty-nine patients were given an equivalent initial treatment with CHOP or CHOP plus methotrexate. The association between MIs and survival was evident also in this subgroup. The results indicate that survival is extremely poor for patients with advanced diffuse nodal lymphomas of unfavourable histology and a high mitotic count. It seems especially important to evaluate alternative chemotherapy regimens, suggested to be more effective than current programmes, in this subset of patients.
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| 57. |
- Burnet, N G, et al.
(författare)
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Prediction of normal-tissue tolerance to radiotherapy from in-vitro cellular radiation sensitivity.
- 1992
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Ingår i: Lancet. - 0140-6736. ; 339:8809, s. 1570-1
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Tidskriftsartikel (refereegranskat)abstract
- The success of radiotherapy depends on the total radiation dose, which is limited by the tolerance of surrounding normal tissues. Since there is substantial variation among patients in normal-tissue radiosensitivity, we have tested the hypothesis that in-vitro cellular radiosensitivity is correlated with in-vitro normal-tissue responses. We exposed skin fibroblast cell lines from six radiation-treated patients to various doses of radiation and measured the proportions surviving. There was a strong relation between fibroblast sensitivity in vitro and normal-tissue reactions, especially acute effects. Assessment of radiosensitivity could lead to improved tumour cure rates by enabling radiation doses to be tailored to the individual.
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| 58. |
- Burnet, N G, et al.
(författare)
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The relationship between cellular radiation sensitivity and tissue response may provide the basis for individualising radiotherapy schedules.
- 1994
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Ingår i: Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology. - 0167-8140. ; 33:3, s. 228-38
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Tidskriftsartikel (refereegranskat)abstract
- There is a wide variation in normal tissue reactions to radiotherapy and in many situations the severity of these reactions limits radiotherapy dose. Clinical fractionation studies carried out in Gothenburg have demonstrated that a large part of the spectrum of normal tissue reactions is due to differences in individual normal tissue sensitivity. If this variation in normal tissue reactions is due to differences in intrinsic cellular radiosensitivity, it should be possible to predict tissue response based on measurement of cellular sensitivity. Here we report the initial results of a study aimed at establishing whether a direct relationship exists between cellular radiosensitivity and tissue response. Ten fibroblasts strains, including four duplicates, were established from a group of patients in the Gothenburg fractionation trials who had received radiotherapy following mastectomy. Skin doses were measured and both acute and late skin changes were observed following radiotherapy. Right and left parasternal areas were treated with different dose fractionation schedules. Clonogenic assays were used to assess intrinsic cellular radiosensitivity, and all experiments were carried out without prior knowledge of the clinical response, or which strains were duplicates. Irradiation was carried out using 60Co gamma-rays at high dose-rate (HDR) of 1-2 Gy/min and low dose-rate (LDR) of 1 cGy/min. A spectrum of sensitivity was seen, with SF2 values of 0.17-0.28 at HDR and 0.25-0.34 at LDR, and values of D0.01 of 5.07-6.38 Gy at HDR and 6.43-8.12 Gy at LDR. Comparison of the in vitro results with the clinical normal tissue effects shows a correlation between cellular sensitivity and late tissue reactions, which is highly significant with p = 0.02. A correlation between cellular sensitivity and acute effects was noted in the left-sided parasternal fields, but not the right. This is thought to be coincidental, and without biological significance. Our results suggest that cellular sensitivity might form the basis for the development of an assay system capable of predicting late normal tissue effects to curative radiotherapy, which might allow dose escalation in some patients. Increased local control and cure, with unchanged or improved normal tissue complications, could result from such individualised radiotherapy prescriptions.
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| 59. |
- Choong, P F, et al.
(författare)
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Prognostic value of Ki-67 expression in 182 soft tissue sarcomas. Proliferation--a marker of metastasis?
- 1994
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Ingår i: APMIS : acta pathologica, microbiologica, et immunologica Scandinavica. - 1600-0463. ; 102:12, s. 915-924
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Tidskriftsartikel (refereegranskat)abstract
- Soft tissue sarcomas (STS) are characterized by deregulated proliferation. Ki-67 is a cell cycle antigen which may be elevated in proliferative states. We analysed Ki-67 expression in fixed and embedded tissues from STS in order to examine associations between proliferation, primary tumour characteristics, and metastasis. One hundred and eighty-two adult patients with trunk wall or extremity STS were treated at our institution between 1980 and 1992 (35 developed local recurrence and 56 developed metastases). Median follow-up time for survivors was 6 years (1-13). We used a semiquantitative score to the assess percentage of Ki-67-positive cells: < or = 10% (n = 86), > 10-25% (n = 57), > 25-50% (n = 30), > 50-75% (n = 7), > 75-100% (n = 2). Increasing Ki-67 expression correlated positively with tumour size, malignancy grade, necrosis, vascular invasion, S-phase fraction, and metastasis. A Ki-67 index Ki-D < or = 10% (n = 86) and > 10% (n = 96) defined two groups who had 84% and 56% 3-year metastasis-free survival (p = 0.0001), respectively. Tumours with Ki-D > 10 were typically large, high grade, necrotic, DNA aneuploid, and had intravascular invasion and a higher S-phase fraction. Ki-67 expression may be helpful in predicting survival of patients with soft tissue sarcomas.
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| 60. |
- Dictor, Michael, et al.
(författare)
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Flow cytometric DNA content in Kaposi's sarcoma by histologic stage. Comparison with angiosarcoma
- 1991
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Ingår i: Analytical and Quantitative Cytology and Histology. - 0884-6812. ; 13:3, s. 201-208
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Tidskriftsartikel (refereegranskat)abstract
- Kaposi's sarcoma occurs as a multicentric proliferation of endothelial cells. A lesion may progress through several histologic stages, culminating in a lesion consisting of spindle cells with marked nuclear atypia that may be indistinguishable from angiosarcoma. To assess the relationship between the nuclear DNA content and the stage, 29 paraffin-embedded biopsy specimens from 25 cases of Kaposi's sarcoma were classified according to their histologic stage and flow cytometric DNA ploidy status. The findings were compared with those in 14 angiosarcomas (5 postmastectomy angiosarcomas, 6 other cutaneous angiosarcomas and 3 angiosarcomas of deep tissues). The Kaposi's sarcoma specimens studied included samples with irregular lymphatic-like channels (stage 1), transition to spindle cells (stage 1t2), nodular spindle-cell aggregates (stage 2), scattered atypical spindle cells (stage 2t3) and histologic features indistinguishable from those of angiosarcoma (stage 3). Of the 25 Kaposi's sarcoma specimens of stage 2 or less, 17 had a diploid DNA distribution while an additional 8 had broad diploid G0G1 peaks (peridiploid, with a coefficient of variation greater than 7.5%, present in similar proportions in stages 1, 1t2 and 2). One of three stage 2t3 lesions showed tetraploidy while the single stage 3 specimen (from the leg) was aneuploid, with a DNA index (DI = 1.16) similar to that of four of the five postmastectomy angiosarcomas (DI = 1.14 to 1.20). An additional three angiosarcomas also showed nondiploid distributions (DI = 1.16, 1.98 and 2.13, respectively); the remainder were diploid or peridiploid. These results support previous cytogenetic data suggesting a normal karyotype in Kaposi's sarcoma up to stage 2, with atypia beginning as cells acquire numerical and structural chromosomal aberrations.
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