Influence Of A New Sansalvamide A Derivatives On Breast Cancer Cell And Telomerase Activity

Background: Sansalvamide A (abbreviated San A) is isolated from themarine fungus (genus Streptomyces shuttle) is a cyclic peptide substances,hasbeen showed to have significant anticancer activities.In this study,wedetermined the effects of a novel Sansalvamide A derivative H-10on theproliferation and telemerase regulation in breast cancer cell lines (MCF-7andMDA-MB-231). In order to investigate the effects of different concentrationsof H-10on human breast cancer lines morphologh,growth and on theexpression of telemerase activity.and to explore its mechanisms of apoptosisfrom gene and protein level,so as to provide theoretical and experimental basisfor the clinical treatment of breast cancer.Methods:1Different concentrations of H-10and the breast cancer cell linesco-cultured after24h, and the morphological change was analyzed by opticalmicroscopy.2After treated by H-10(01020406080μM）for24h, the growthinhibition and cells viability of breast cancer cells were analyzed by MTTassay.3The effect of H-10(40μ M) on cell growth of breast cancercells(MCF-7and MDA-MB-231) were assessed by growth curve.4The effect of H-10(40μM) on the invasion of breast cancer cells(MCF-7and MDA-MB-231)were examined by scratch assays.5Telomeric Repeat Amplification Protocol (TRAP) assays wasperformed to investigate the activity of telemerase of breast cancer cells(MCF-7and MDA-MB-231) were treated with different concentrations ofH-10.6Cell-cycle distribution and apoptosis in breast cancer cells were evaluated by Flow cytometry(FCM) after treated with40μM of H-10for24h.7The c-Myc,Bcl-2and hTERT mRNA expression was examined byRT-PCR assay after treated with different concentrations of H-10for24h.8The change of c-Myc,Bcl-2and hTERT protein expression wasexamined by Western blot after treated with different concentrations of H-10for24h.Result:1Following the increasing concentrations of H-10,the cells morpologyand volume have changed,and apoptotic bodies were detected.however,whichis all uniform and growth intensively of the cells in control group.2H-10could obviously inhibit the growth of breast cancer cells(MCF-7and MDA-MB-231),which was related with the different concentration ofH-10and time of culture.Compared to the control group,the difference wassignificant(p﹤0.05).3After treated with H-10for48h in vitro,the growth ability of breastcancer cells(MCF-7and MDA-MB-231) decreased significantly compared tothe control group,the difference was significant(p﹤0.05).4After treated with H-10(20uM),the diameters of scratch becamebroader that of the control group(p﹤0.05).5After treated with treated with different concentrations of H-10,thetelomerase activity was significantly inhibited,and which is a dose dependentdecrease.6FCM analyses showed that the apoptosis rate of breast cancercells(MCF-7and MDA-MB-231)have changed after treated with the differentconcentration of H-10.The propotion of MCF-7and MDA-MB-231cells inthe G0/G1phase was elevated while the propotion MCF-7and MDA-MB-231in the phase reduced in a concentration depended manner,the different wassignificant(p﹤0.05).7The effect of H-10on the of MCF-7and MDA-MB-231cells detectedby RT-PCR showed that,H-10could down-regulate the expression of c-myc,bcl-2,hTERT mRNA,and in a concentration depended manner,thedifferent was significant(p﹤0.05).8Western blot revealed that H-10can also down-down-regulate the expressionlevel of c-myc,bcl-2,hTERT protein,consistent with the gene level(p﹤0.05).Conclusions:In vitro,H-10can significantly inhibited the growth of MCF-7andMDA-MB-231cells and telomerase activity,and could down-regulate theexpression level of c-myc,bcl-2,hTERT,as a result of inhibited the activity oftelemerase and cells proliferation,and lead to apoptosis,have obviousantitumor effect.