Prognostic factors for recurrent breast cancer: univariate and multivariate analyses including histologic grade and amplification of the c-erbB-2 proto-oncogene.

Post-recurrence survival was examined in 62 breast cancer patients who had undergone curative radical mastectomies between 1974 and 1976 and suffered recurrences within 127 months of surgery. The prognostic value of 11 clinical, histological and genetic factors, including histologic grade of malignancy and amplification of oncogenes was analyzed using univariate and multivariate analyses. Not only the site of first recurrence, clinical stage and size of primary tumor at initial surgery, and disease-free period, but also histologic grade and amplification of the c-erbB-2 proto-oncogene were significant prognostic indicators of recurrent breast cancer. Multivariate analysis using Cox's regression model, histologic grade and amplification of c-erbB-2 in the primary tumor, as well as clinical stage at surgery and site of first recurrence, were shown to be major independent prognostic factors of recurrent breast cancer. Because post-recurrence prognosis was strongly influenced by the clinical, histological and genetic status of the primary breast cancer, appropriate evaluation of the primary tumor for the grade of aggressiveness of the cancer cells, as well as the extent of cancer spread, seem to be important.     

Biology of tumors of the peripheral nervous system

Tumors of the peripheral nervous system include neuroblastomas, pheochromocytomas, and neuroepitheliomas. Neuroblastomas and pheochromocytomas are adrenergic in origin and share certain genetic features, whereas neuroepitheliomas are thought to be cholinergic and are characterized by distinct genetic features. Neuroblastomas are characterized by deletion of the short arm of chromosome 1 (1p), amplification of theMYCN proto-oncogene, and hyperdiploidy in subsets of tumors. All three of these genetic features have prognostic value in subsets of patients. Allelic loss of 14q also occurs with increased frequency, but the prognostic importance of this abnormality is not known yet. Pheochromocytomas have not been studied as extensively, but allelic loss for 1p appears to be a frequent change, and no clear examples of oncogene activation have been identified to date. Neuroepitheliomas are characterized by translocation between chromosomes 11 and 22. Although they have a characteristic pattern of proto-oncogene expression, it is not clear that any of these oncogenes are activated specifically, and no sites of allelic loss have been identified to date. Thus, cytogenetic and molecular analysis of neuroblastomas, pheochromocytomas, and neuroepitheliomas are useful in distinguishing them from each other and from other tumors in selected cases. Furthermore, certain genetic markers are useful in predicting clinical behavior, especially for neuroblastoma.Abbreviations RFLP Restriction Fragment Length Polymorphism - LOH Loss Of Heterozygosity - dmins Double-minute chromatin bodies - HSR Homogeneously Staining Region - N myc-amplification of MYCN     

MYEOV: a candidate gene for DNA amplification events occurring centromeric to CCND1 in breast cancer

Rearrangements of chromosome 11q13 are frequently observed in human cancer. The 11q13 region harbors several chromosomal breakpoint clusters found in hematologic malignancies and exhibits frequent DNA amplification in carcinomas. DNA amplification patterns in breast tumors are consistent with the existence of at least 4 individual amplification units, suggesting the activation of more than 1 gene in this region. Two candidate oncogenes have been identified, CCND1 and EMS1/CORTACTIN, representing centrally localized amplification units. Genes involved in the proximal and distal amplicons remain to be identified. Recently we reported on a putative transforming gene, MYEOV, mapping 360 kb centromeric to CCND1. This gene was found to be rearranged and activated concomitantly with CCND1 in a subset of t(11;14)(q13;q32)-positive multiple myeloma (MM) cell lines. To evaluate the role of the MYEOV gene in the proximal amplification core, we tested 946 breast tumors for copy number increase of MYEOV relative to neighboring genes or markers. RNA expression levels were studied in a subset of 72 tumors for which both RNA and DNA were available. Data presented here show that the MYEOV gene is amplified in 9.5% (90/946) and abnormally expressed in 16.6% (12/72) of breast tumors. Amplification patterns showed that MYEOV was most frequently coamplified with CCND1 (74/90), although independent amplification of MYEOV could also be detected (16/90). Abnormal expression levels correlated only partially with DNA amplification. MYEOV DNA amplification correlated with estrogen and progesterone receptor-positive cancer, invasive lobular carcinoma type and axillary nodal involvement. In contrast to CCND1 amplification, no association with disease outcome could be found. Our data suggest that MYEOV is a candidate oncogene activated in the amplification core located proximal to CCND1.     

Novel monoclonal antibody specific for the de2-7 epidermal growth factor receptor (EGFR) that also recognizes the EGFR expressed in cells containing amplification of the EGFR gene

In some respects, the EGFR appears to be an attractive target for tumor-targeted antibody therapy: it is overexpressed in many types of epithelial tumor and inhibition of signaling often induces an anti-tumor effect. The use of EGFR specific antibodies, however, may be limited by uptake in organs that have high endogenous levels of the wild type EGFR such as the liver. The de2-7 EGFR (or EGFRvIII) is a naturally occurring extracellular truncation of the EGFR found in a number of tumor types including glioma, breast, lung and prostate. Antibodies directed to this tumor specific variant of the EGFR provide an alternative targeting strategy, although the lower proportion of tumors that express the de2-7 EGFR restricts this approach. We describe a novel monoclonal antibody (MAb 806) that potentially overcomes the difficulties associated with targeting the EGFR expressed on the surface of tumor cells. MAb 806 bound to de2-7 EGFR transfected U87MG glioma cells (U87MG.Delta 2-7) with high affinity (approximately 1 x 10(9) M(-1)), but did not bind parental cells that express the wild type EGFR. Consistent with this observation, MAb 806 was unable to bind a soluble version of the wild type EGFR containing the extracellular domain. In contrast, immobilization of this extracellular domain to ELISA plates induced saturating and dose response binding of MAb 806, suggesting that MAb 806 can bind the wild type EGFR under certain conditions. MAb 806 also bound to the surface of A431 cells, which due to an amplification of the EGFR gene express large amounts of the EGFR. Interestingly, MAb 806 only recognized 10% of the total EGFR molecules expressed by A431 cells and the binding affinity was lower than that determined for the de2-7 EGFR. MAb 806 specifically targeted U87MG.Delta 2-7 and A431 xenografts grown in nude mice with peak levels in U87MG.Delta 2-7 xenografts detected 8 h after injection. No specific targeting of parental U87MG xenografts was observed. Following binding to U87MG.Delta 2-7 cells, MAb 806 was rapidly internalized by macropinocytosis and subsequently transported to lysosomes, a process that probably contributes to the early targeting peak observed in the xenografts. Thus, MAb 806 can be used to target tumor cells containing amplification of the EGFR gene or de2-7 EGFR but does not bind to the wild type EGFR when expressed on the cell surface.     

Tumour-amplified kinase BTAK is amplified and overexpressed in gastric cancers with possible involvement in aneuploid formation

Our recent analysis of gastric cancers using comparative genomic hybridization (CGH) revealed a novel high frequent copy number increase in the long arm of chromosome 20. Tumour-amplified kinase BTAK was recently cloned from breast cancers and mapped on 20q13 as a target gene for this amplification in human breast cancers. In the study presented here, we analysed BTAK copy-number and expression, and their relation to the ploidy pattern in 72 primary gastric cancers. Furthermore, wild-type BTAK and its deletion mutants were transfected to gastric cancers to examine changes in cell proliferation and DNA ploidy pattern. Evaluation of 72 unselected primary gastric cancers found BTAK amplification in 5% and overexpression in more than 50%. All four clinical samples with BTAK amplification showed aneuploidy and poor prognosis. Transfection of BTAK in near-diploid gastric cancers induced another aneuploid cell population. In contrast, the c-terminal-deleted mutant of BTAK induced no effect in DNA ploidy pattern and inhibited gastric cancer cell proliferation. These results suggest that BTAK may be involved in gastric cancer cell aneuploid formation, and is a candidate gene for the increase in the number of copies of the 20q, and thus may contribute to an increase in the malignant phenotype of gastric cancer.     

穿琥宁注射液降解动力学研究

目的：研究穿琥宁注射液在不同pH值、不同温度、不同光照条件下降解反应的动力学参数。方法：用高效液相色谱法测定含量，井运用经典恒温法、多元线性模型探讨其稳定性，用阿累尼乌斯公式预测其有效期和活化能。结果：穿琥宁注射液的降解反应为假一级动力学。结论：穿琥宁注射液在pH值6．0时最稳定，有效期为24个月。为进一步探讨其阵解机制提供必要的实验结果和数据。     

端粒酶活性表达及p53异常在非小细胞肺癌中表达及临床意义

目的：研究端粒酶活性及 p53异常在非小细胞肺癌 (nonsmall cell lung cancer, NSCLC)中的表达及其相互关系。方法：用端粒重复扩增（ telomeric repeat amplification protocol, TRAP）法检测 NSCLC组织、癌旁非癌肺组织、肺良性病变组织端粒酶活性,用 Western blot印迹法检测 NSCLC组织 p53蛋白表达。结果：端粒酶活性表达率为： NSCLC 93.02％ (80/86),癌旁非癌肺组织 9.33％ (7/75),肺良性病变组织 27.27％ (3/11), NSCLC组织端粒酶活性表达率显著高于癌旁非癌肺组织及肺良性病变,端粒酶活性表达率在不同组织类型、细胞分化、肿瘤大小、病理分期间差别不显著; NSCLC p53异常为 51.42％（ 36／ 70）, p53异常在Ⅰ、Ⅱ期与Ⅲ、Ⅳ期之间,Ⅰ级与Ⅱ、Ⅲ级之间差异有统计学意义;端粒酶活性表达与 p53异常无显著关联（ P >0.05）;结论： NSCLC标记物中,端粒酶活性表达较 p53敏感, p53对 NSCLC分期分级有帮助,端粒酶活性表达与 p53异常在 NSCLC发生发展中可能是两个独立的因素。