Relationship between the Expression of Apoptosis-Related Proteins and Chemosensitivity in Gastric Cancer Cell Lines

ABSTRACT

BACKGROUND: There has been a growing realization that a variety of anticancer drugs can induce apoptotic cell death. In the present study, an attempt was made to investigate the responsiveness of gastric cancer cells to various anticancer drugs and to identify which apoptosis-related proteins could be correlated to chemosensitivity. METHODS: Nine human Korean gastric cancer cell lines (SNU-1, -5, -16, -484, -601, -620, -638, -668, and -719) were analyzed. The cytotoxicity of each cell line to camptothecin, cisplatin, mitomycin C, vincristine, 5-FU, epirubicin, and doxorubicin was determined by using a MTT (dimethylthiazole- diphenyltetrazolium-bromide) assay. Apoptosis-related proteins (p53, p21, Bcl-2, Bcl-x, and Bax) were detected using a Western blot assay. RESULTS: Of the nine gastric cancer cell lines, SNU-1 was resistant while SNU-5 was sensitive to anticancer drugs. Mutated p53 was detected in all the cell lines. The highest expression of Bcl-2 was observed in SNU-1 while less or no expression of Bcl-2 was observed in SNU-5, -484, and -601. Bcl-xL was less expressed in SNU-5 than in the other cell lines. CONCLUSIONS: Chemosensitivity in gastric cancer cell lines was correlated mainly with the level of Bcl-2 and partly with that of Bcl-xL. There was no correlation between the chemosensitivity and other apoptosis-related proteins, such as p21, p53, Bax, and Bcl-xS in the studied gastric cancer cell lines.