Platycodon grandiflorum saponin D enhances the sensitivity of human rectal cancer cell strain SW1463/Oxa with drug resistance to oxaliplatin

Abstract

Objective To investigate the enhancing effect of platycodon grandiflorum saponin D on the sensitivity of human rectal cancer drug-resistant cell line SW1463 to oxaliplatin (Oxa). Methods Human rectal cancer cell line SW1463 was collected to establish a stable oxaliplatin-resistant cell strain SW1463/Oxa. The constructed cell strain SW1463/Oxa was randomly divided into platycodon grandiflorum saponin D group, Oxa group, platycodon saponin D+Oxa group and control group. The cell proliferation curve was detected by MTT. Deoxyribonucleic acid methyltransferase 3a (DNMT3a), phosphorylated histone γ-H2AX, DNA double strand repair protein RAD51 and signal transducer and activator of transcription 3(STAT3) messenger RNA (mRNA) expression were detected by RT-qPCR. DNMT3a, γ-H2AX, RAD51, STAT3 protein expression and phosphorylated STAT3(p-STAT3) level were detected by Western blot. Results Human rectal cancer drug resistant cell strain SW1463/Oxa was successfully constructed. Compared with the control group and Oxa group, the cell proliferation, DNMT3a, RAD51, STAT3 mRNA and protein expression and p-STAT3 level of platycodon saponin D group and platycodon saponin D+Oxa group decreased(P＜0.05), and the expression of γ-H2AX mRNA and protein increased(P＜0.05). Conclusions Platycodon grandiflorum saponin D may enhance the chemo-sensitivity of human rectal cancer drug-resistant cell strain SW1463/Oxa to Oxa, and the potential mechanism is inhibition of expression of DNMT3a, RAD51, STAT3 and promotion of expression of γ-H2AX.

Keywords

• platycodon grandiflorum saponin d|deoxyribonucleic acid methyltransferase 3a|rectal cancer|susceptibility