THE SUPPRESSIIVE EFFECT OF CISPLATIN COMBINED WITH HYPERTHERMIA ON HUMAN GASTRIC ADENOCARCINOMA CELL LINES IN VITRO

Objective To investigate the anticancer effect of CDDP combined with hyperthermia on human gastric adenocarcinoma cell lines SGC-7 901 and BGC-823.Methods The working concentrations of CDDP against gastric cancer cell lines were determined by MTT assay that has been developed for quantitative evaluation of the proliferation of cells.Then hyperthermia and chemotherapy were used singly or concurrently and the cell survival rates were obtained at 24 h or 48 h.The anticancer effect was evaluated with Veleriote method.The apoptosis rates of BGC-823 were determined at 24 h by flow cytometric analyses.Results The concentrations were determined as those of IC40-IC50 at 24 h.They turned out to be 5 μg/mL and 1 μg/mL respectively. 43 ℃() 60 min hyperthermia showed obvious inhibition of the two cell lines at 24 h(P0.05),but it did not occur at 48 h.CDDP 5 μg/mL chemotherapy or thermochemotherapy showed obvious inhibition of SGC-7 901 at 24 h and 48 h(P0.01).CDDP 5 μg/mL combined with hyperthermia showed ob vious synergism at 24 h and subaddictive effect at 48 h to SGC-7 901.CDDP 1 μg/mL chemoth-erapy or thermochemotherapy obviously inhibited the growth of BGC-823 at 24 h and 48 h(P0.01).CDDP 1 μg/mL combined with hyperthermia showed obvious synergism to BGC-823 at 24 h and 48 h.According to flow cytometric analyses at 24 h,CDDP 1 μg/mL chemotherapy and thermochemotherapy could obviously increase the apoptosis rates of BGC-823(P0.01).Conclusions CDDP 5 μg/mL combined with hyperthermia showed obvious synergism to SGC-7 901 at 24 h and subaddictive effect at 48 h.CDDP 1 μg/mL combined with hyperthermia showed obvious synergism to BGC-823 at 24 h and 48 h.The synergism might be related with the increase of cell apoptosis rates.