Quantitative analysis of expression levels of bax, bcl-2, and survivin in cancer cells during cisplatin treatment.
Cisplatin (CDDP) exerts significant activity against a wide variety of human malignancies. However, sensitivity to CDDP differs among cancer cells. CDDP induces apoptosis in cancer cells. In the present study, to evaluate good markers of chemo-sensitivity or chemo-resistance of cancer cells, the correlation between occurrence of apoptosis and the changes in expression levels of messenger RNA (mRNA) of three genes (bax, bcl-2, and survivin) in cancer cell lines during CDDP treatment were investigated. Cells (MKN-45, LoVo, and PANC-1) were incubated with CDDP (10 microg/ml). The percentage of cells in sub-G1 fraction was measured by flow cytometry. The changes in expression levels of three genes (bax, bcl-2, and survivin) during CDDP treatment were evaluated by real-time reverse transcriptase-polymerase chain reaction (RT-PCR). The percentage of cells in sub-G1 fraction increased after a shorter incubation with CDDP in LoVo cells and also increased between 12 and 24 h CDDP treatment in MKN-45 cells. On the other hand, even with a 24 h incubation with CDDP, the percentage of cells in sub-G1 fraction did not change in PANC-1 cells. The expression level of bax mRNA significantly increased after 24 h treatment with CDDP in MKN-45 cells and it significantly increased after 12 h treatment with CDDP in LoVo cells. Also, in LoVo cells, the expression level of bcl-2 mRNA decreased after 24 h treatment with CDDP. On the other hand, during CDDP treatment, the expression levels of bcl-2 and survivin mRNA significantly increased in PANC-1 cells. These findings indicate that during chemotherapy, changes in expression levels of bax, bcl-2, and survivin may provide information about chemo-sensitivity or the chemo-resistance of tumors.
Ikeguchi
Masahide
M
First Department of Surgery, Faculty of Medicine, Tottori University, Yonago 683-8504, Japan. masaike@grape.med.tottori-u.ac.jp
Nakamura
Seiichi
S
Kaibara
Nobuaki
N
D000970:Antineoplastic Agents / Q000627:therapeutic use*; D017209:Apoptosis; D002945:Cisplatin / Q000627:therapeutic use*; D018076:DNA, Complementary / Q000378:metabolism; D019008:Drug Resistance, Neoplasm; D006801:Humans; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins / Q000096:biosynthesis*; D009363:Neoplasm Proteins; D009369:Neoplasms / Q000188:drug therapy* / Q000378:metabolism*; D011518:Proto-Oncogene Proteins / Q000096:biosynthesis*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000096:biosynthesis*; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D000077022:Survivin; D013997:Time Factors; D014407:Tumor Cells, Cultured; D051028:bcl-2-Associated X Protein
D000970:Antineoplastic Agents; C494826:BAX protein, human; C107489:BIRC5 protein, human; D018076:DNA, Complementary; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D009363:Neoplasm Proteins; D011518:Proto-Oncogene Proteins; D019253:Proto-Oncogene Proteins c-bcl-2; D012333:RNA, Messenger; D000077022:Survivin; D051028:bcl-2-Associated X Protein; D002945:Cisplatin