| Backgroud: Colorectal cancer(CRC)is currently one of the most common malignancy tumors in the world.The morbidity and mortality rate increase year by year.How to effectively prevent and treat CRC has been a key question in the medical field.However,most anti-tumor chemotherapy shows lots of toxic and side effects.There is an urgent need for new therapeutic agents for CRC patients.A number of anti-cancer drugs have been isolated from plants because of high efficacy and low toxicity.Luffa echinata Roxb.(LER),a slender herb which grows widely in the Bengal,Gujarat and Uttar Pradesh regions of India,is commonly known as “Bindal” in Hundi and belongs to the Cucurbitaceous.Some reports on its biologically active compounds have already been reports.However,little is known about the effect of LER against CRC so far.Our previous study demonstrated that extract of LER inhibited colon cancer cells proliferation.However,the mechanisms of its anti-proliferation effect remain unclear.This study was to further investigate the mechanism of extract of LER inhibiting colon cancer cells proliferation,and to provide a theoretical reference for the application of LER.Objectives: Our research purpose was to evaluate whether Luffa echinata Roxb.can inhibit the proliferation of the human colon cancer cells HT-29 in vitro,identify that Luffa echinata Roxb.has antitumous effect and the molecular mechanism of Luffa echinata Roxb.inducing the human colon cancer cells apoptosis.Methods: We used the human colon cancer cell line HT-29 as a model.The anti-proliferative activity was evaluated by MTT.The Apoptosis cellular morphological changes were observed by light microscopy,the changes of cellcycle,reactive oxygen species(ROS)generation and mitochondrial transmembrane potential(MMP)in cells were analyzed by flow cytometer.Expression of apoptotic-related genes in LER extract-treated cells were checked by reverse transcription-polymerase chain reaction(RT-PCR)analysis.Results: The extract of the fruits of Luffa echinata Roxb.inhibited the proliferation of human colon cancer cells(HT-29)in both dose-dependent and time-dependent manners and obvious shrinkage and destruction of the monolayer were observed in LER-treated cells by light microscopy,but not in untreated cells.Analysis of the cell cycle after treatment of HT-29 cells with various concentrations indicated that LER extracts inhibited the cellular proliferation of HT-29 cells via G2/M phase arrest of the cell cycle.The Reactive oxygen species(ROS)level determination revealed that LER extracts induced apoptotic cell death via ROS generation.In addition,LER treatment led to a rapid drop in mitochondrial membrane potential(MMP)as a decrease in fluorescence.The transcripts of several apoptosis-related genes were investigated by RT-PCR analysis.The caspase-3transcripts of HT-29 cells significantly accumulated and the level of Bcl-XL mRNA was decreased after treatment with LER extract.Furthermore,the ratio of mitochondria-dependent apoptosis genes(Bax and Bcl-2)was sharply increased from 1.6 to 54.1.These experiments suggest that LER has anticancer properties via inducing the apoptosis in colon cancer cells,which provided the impetus for further studies on the therapeutic potential of LER against human colon carcinoma.Conclusion: Accordingly,LER extracts could suppress the growth of the human colon cancer cell and induce apoptosis in vitro in some concentration extent.The signal channel of LER extracts inducing the human colon cancer cell apoptosis was through the mitochondrial caspase-dependent cell death pathway.Thus,Luffa echinata Roxb.should be considered as a potential therapeutic in the treatment of human colon cancer.However,additional studies to determine its in vivo biological activities and to identify the phytochemicals responsible for their anticancer activities will be needed.The exact apoptosis mechanisms induced by LER extracts were about the change of the ROS,MMPand Bcl-2/Bax.But the effect of LER extracts in vivo was still need to be researched in future. |
PDF Full Text Request