The mechanisms of apoptosis induced by hydroxycamptothecin in gastric cancer cells / 中华消化杂志

ABSTRACT

Objective To study the mechanisms of Hydroxycamptothecin (HCPT) induced apoptosis of gastric cancer cells by detecting the expressions of p53, c myc, bcl 2, bcl xl, bcl xs genes. Methods Apoptosis of gastric cancer cells (SGC 7901,MKN 45) was measured by TUNEL and flow cytometry. The levels of mRNA and protein of p53, c myc, bcl 2, bcl xl,bcl xs genes were determined by reverse transcriptase polymerase chain reaction analysis and immunohistochemistry, respectively. Results Gastric cancer cells SGC 7901, MKN 45 presented some morphologic features of apoptosis, including cell shrinkage, nuclear condensation, DNA fragmentation, formation of apoptotic bodies, after 12 hours expourse to HCPT. Some typical subdiploid peaks before G0/G1 phase were observed. The apoptotic rates of SGC 7901, MKN 45 were 21.88% and 12.34%, respectively. The levels of p53 and bcl 2 mRNA and protein were downregulated after treated with HCPT in SGC 7901 cells. The levels proteins of c myc, bcl xl, bcl xs were unchanged after expourse to HCPT in SGC 7901 cells. The levels of p53 mRNA and protein were increased after treated with HCPT in MKN 45 cells. While the expressions of protein of bcl 2, c myc, bcl xl, bcl xs genes were not affected by HCPT in MKN 45 cells. Conclusion The results have showed HCPT induced apoptosis in gastric cancer cells might be regulated through influencing the expressions of p53 and bcl 2 genes.