Everamplification of GER-2/neu Oncogene Detected by Differential PCR and its Prognostic Significance in Advanced Epithelial Ovarian Cancer / 대한암학회지

PURPOSES: The objectives of this study were to investigate the prevalence of HER-2/neu oncogene amplification by differential polymerase chain reaction and to examine whether HER-2/neu oncogene overamplification has any prognostic significance in advanced epithelial ovarial cancer patients. MATERIALS AND METHODS: The study population comprised thirty patients with stage III or IV epithelial ovarian cancer who were managed at Asan Medical Center between January 1994 and December 1996. Fresh frozen tumor samples of primary lesion were analysed by differential polymerase chain reaction to assess amplification of HER-2/neu oncogene. The correlation between HER-2/neu oncogene overamplification and histologic subtype or tumor grade or serum CA 125 level after second chemotherapy were evaluated using chi-square test, and for survival analysis, Kaplan-Meier curves were plotted and the differences between the curves were tested for significance using Log-rank test. RESULTS: HER-2/neu oncogene was amplified in all of the cases (100% 30/30), but significant overamplification [gene copy number > or =1.5 a.u.(arbitrary unit)] was observed in 46.7% (14/30). There was no significant correlation between HER-2/neu oncogene overamplification and histologic subtype or tumor grade or serum CA 125 level after second chemotherapy and there was no correlation between HER-2/neu oncogene overamplification and overall survival. CONCLUSION: The prevalence of HER-2/neu oncogene overamplification is 46.7%, but it may not be a significant prognostic factor in advanced epithelial ovarian cancers.

Amplification and Overexpression of Cyclin D1 in Head and Neck Squamous Cell Carcinomas / 대한이비인후과학회지

BACKGROUND: Overexpression of the cell cycle control gene, cyclin D1 may, at least in some tumor types, provide a prognostic marker. Cyclin D1 is expressed during the G1 phase of the cell cycle and becomes associated with its catalytic partner CDK4 or CDK6. This association may overcome the G1 arrest. OBJECTIVES: To establish the frequency of cyclin D1 protein overexpression and to evaluate its correlation with cyclin D1 gene amplification and its correlation with clinico-pathologic variables that are used in clinical practice. MATERIALS AND METHODS: The cyclin D1 gene amplification was estimated with the differential polymerase chain reaction(PCR) and cyclin D1 protein overexpression was evaluated with immunohistochemical study in 32 cases of resectable head and neck squamous cell carcinoma(SCC). The presence or absence of cyclin D1 protein overexpression was correlated with anatomical sites, T stage, nodal involvement, pathologic grade and survival rate. RESULTS: Six SCC cases(18.7%) showed the amplification of cyclin D1 gene. A highly statistical correlation between cyclin D1 gene amplification and cyclin D1 protein overexpression was noted(p0.05). But overexpression of cyclin D1 protein was associated with a poor survival of these cases(p<0.05). CONCLUSIONS: Overexpression of cyclin D1 is the independent prognostic factor for the head and neck squamous cell carcinoma. The cyclin D1 gene amplification results in the overexpression of cyclin D1 protein. But additional genetic mechanisms are involved in the protein overexpression. Therefore, cyclin D1 oncogene may be important in tumorigenesis in the head and neck squamous cell carcinoma.