Abstract

PURPOSE
Sensitivity of tumor cells to chemotherapeutic regimen may be accentuated by their abnormal expression of oncogene. p53 is required for the efficient activation of apoptosis following irradiation or treatment with chemotherapeutic agents. The aim of this study was to evaluate the relationship between chemosensitivity and apoptosis related proteins such as p53, bcl-2 in small cell lung cancer cell lines. MATERIAL AND METHODS: Six human small cell lung cancer cell lines, NCI-H69, NCI-H128, NCI-H1436, NCI-H1092, derived from untreated and treated patients were tested for chemo sensitivity and the expression of the p53, bcl-2 genes were examined in each cell lines with western blot analysis. We used 4 drugs including adriamycin, cisplatin, vincristine and VP-16.
RESULTS
NCI-H128 was the most sensitive cell line to four drugs. NCI-H82 and NCI-H1092 were highly resistant to VP-16, adriamycin and vincristine and determination of an IC50 was not possible. In western blot analysis, NCI-H128 alone was strong positive to p53 monoclonal antibody and the rest of cell lines were negative. All but NCI-H128 were positive to bcl-2 monoclonal antibody. NCI-H128 which was strong positive to p53 and negative to bcl-2. NCI-H1092 was strong positive to bcl-2 and negative to p53 monoclonal antibody.
CONCLUSION
We were not able to explain the expression of p53 in small cell lung cancer cell lines in relation to senitivity to anti-cancer chemotherapeutic agents. But the expression of bcl-2 in small cell lung cancer cell lines was correlated with the chemosensitivity well.

• Keywords: Small cell lung cancer;p53 protein;bcl-2 protein;Chemosensitivity