The effect of celastrol in combination with 5-fluorouracil on proliferation and apoptosis of gastric cancer cell lines

Background:Despite the availability of chemotherapy drugs such as 5-fluorouracil(5-FU),the treatment of some cancers such as gastric cancer remains challenging due to drug resistance and side effects.This study aimed to investigate the effect of celastrol in combination with the chemotherapy drug 5-FU on proliferation and induction of apoptosis in human gastric cancer cell lines(AGS and EPG85-257).Materials and Methods:In this in vitro study,AGS and EPG85-257 cells were treated with different concentrations of celastrol,5-FU,and their combination.Cell proliferation was assessed using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide(MTT)assay.The synergistic effect of 5-FU and celastrol was studied using Compusyn software.The DNA content at different phases of the cell cycle and apoptosis rate was measured usingflow cytometry.Results:Co-treatment with low concentrations(10%inhibitory concentration(IC10))of celastrol and 5-FU significantly reduced IC50(p<0.05)so that 48 h after treatment,IC50 was calculated at 3.77 and 6.9μM for celastrol,20.7 and 11.6μM for 5-FU,and 5.03 and 4.57μM for their combination for AGS and EPG85-257 cells,respectively.The mean percentage of apoptosis for AGS cells treated with celastrol,5-FU,and their combination was obtained 23.9,41.2,and 61.9,and for EPG85-257 cells 5.65,46.9,and 55.7,respectively.In addition,the 5-FU and celastrol-5-FU combination induced cell cycle arrest in the synthesis phase.Conclusions:Although celastrol could decrease the concentration of 5-fluorouracil that sufficed to suppress gastric cancer cells,additional studies are required to arrive at conclusive evidence on the anticancer effects of celastrol.

In vitro antiproliferative and apoptosis-inducing activities of crude ethyle alcohole extract of Quercus brantii L.acorn and subsequent fractions

Cancer cell resistance to widely used chemotherapeutic agents is gradually developed. Natural products, mainly isolated from medicinal plants, have been considered as valuable sources for herbal anticancer drugs. The present study aimed to evaluate in vitro antiproliferative and apoptosis-inducing activities of crude ethyle alcohole extract and four fractions of Q. brantii acorn. Crude ethyle alcohole extract of Q. brantii acorn was prepared and subjected to fractionation with different polarity. Subsequently, the extract and the fractions wereevaluated for their in vitro antiproliferative activity in two cancerous(Hela and AGS) and one normal(HDFs) cell lines using MTT [3-(4, 5-dimethylthiazol-2ol) 2, 5 diphenyltetrazoliumbromide] assay. To determine whether the cytotoxicity of these compounds involved the induction of apoptosis, Hela cells were treated with IC_(50) concentrations of test compounds, stained with both propidium iodide(PI) and Annexin V-fluorescein isothiocyanate(FITC), and analyzed by flow cytometry. In vitro cytotoxicity assay showed that the cell viability was significantly reduced in a dose-dependent manner following treatment with crude ethyle alcohole extract and Cholophorm and n-Butanol fractions. Based on the probit regression model, antiproliferative activities of crude ethyle alcohole extract, Cholophorm fraction, and n-Butanol fraction on Hela and AGS cells and HDFs cells were significantly different(P < 0.001). The results of flow cytometric analysis showed that crude ethyle alcohole extract and two fractions of Q. brantii acorn induced early apoptotic cell death. These findings suggest that crude ethyle alcohole extract and Cholophorm and n-Butanol fractions of Q. brantii acorn suppress the proliferation of cancer cells through induction of early apoptosis.