AIM: To investigate the signal pathway of honokiol-induced apoptosis on human colorectal carcinoma RKO cells and to evaluate whether p53 and p53-related genes were involved in honokiol-treated RKO cells.METHODS: Cell ...AIM: To investigate the signal pathway of honokiol-induced apoptosis on human colorectal carcinoma RKO cells and to evaluate whether p53 and p53-related genes were involved in honokiol-treated RKO cells.METHODS: Cell cycle distribution and subdiploid peak were analyzed with a flow cytometer and DNA fragment with electrophoresis on agarose gels. Transcriptional level of Bax, Bcl-2, Bid and Bcl-xl was accessed by RT-PCR.Western blotting was used to measure p53 protein expression and other factors related to apoptosis.Proliferation inhibition of two cell lines (RKO, SW480) with high expression of p53 and one cell line with p53 negative expression (LS180) was monitored by MTr assay.RESULTS: Honokiol induced RKO cell apoptosis in a dosedependent manner. The mRNA expression level and proteinlevel of Bid were up-regulated while that of Bcl-xl wasdown-regulated, but no changes in Bax and Bcl-2 were observed. Western blotting showed p53 expression had no remarkable changes in honokiol-induced RKO cell apoptosis. LS180 cells treated with honokiol exhibited apparent growth inhibition like RKO ceils and Sw480 ceils.CONCLUSION: Honokiol can induce RKO cells apoptosis through activating caspase cascade by p53-indepenent pathway.展开更多
AIM: To investigate the anticancer activity of Honokiol on RKO,a human colorectal carcinoma cell line in vitro and in vivo,and to evaluate its possible use in clinic.METHODS: In vitro anticancer activity of honokiol w...AIM: To investigate the anticancer activity of Honokiol on RKO,a human colorectal carcinoma cell line in vitro and in vivo,and to evaluate its possible use in clinic.METHODS: In vitro anticancer activity of honokiol was demonstrated by its induction of apoptosis in tumor cells.We analyzed cell proliferation with MTT assay, cell cycle with flow cytosmeter, DNA fragment with electrophoresis on agarose gels. To test the mechanism of honokiol-induced apoptosis, Westem blotting was used to investigate the factors involved in this process. The pharmacokinetics study of honokiol was tested by high phase liquid chromatography.In in vivo study, Balb/c nude mice were incubated with RKO cells. Honokiol was injected intraperitoneally every other day into tumor bearing Balb/c nude mice.RESULTS: Our results showed that honokiol induced apoptosis of RKO cells in a time- and dose-dependent manner. At 5-10 ug/mL for 48 h, honokiol induced apoptosis through activating Caspase cascades. Pharmacokinetics study demonstrated that, honokiol could be absorbed quickly by intraperitoneal injection, and maintained in plasma for more than 10 h. In nude mice bearing RKO-incubated tumor, honokiol displayed anticancer activity by inhibiting tumor growth and prolonging the lifespan of tumor bearing mice.CONCLUSION: With its few toxicity to normal cells and potent anticancer activity in vitroand in vivo, honokiol might be a potential chemotherapy candidate in treating human colorectal carcinoma.展开更多
基金Supported by the Cheung Kong Scholars Program,National Ministry of Education of China,and Li Ka Shing Foundation,Hong Kong
文摘AIM: To investigate the signal pathway of honokiol-induced apoptosis on human colorectal carcinoma RKO cells and to evaluate whether p53 and p53-related genes were involved in honokiol-treated RKO cells.METHODS: Cell cycle distribution and subdiploid peak were analyzed with a flow cytometer and DNA fragment with electrophoresis on agarose gels. Transcriptional level of Bax, Bcl-2, Bid and Bcl-xl was accessed by RT-PCR.Western blotting was used to measure p53 protein expression and other factors related to apoptosis.Proliferation inhibition of two cell lines (RKO, SW480) with high expression of p53 and one cell line with p53 negative expression (LS180) was monitored by MTr assay.RESULTS: Honokiol induced RKO cell apoptosis in a dosedependent manner. The mRNA expression level and proteinlevel of Bid were up-regulated while that of Bcl-xl wasdown-regulated, but no changes in Bax and Bcl-2 were observed. Western blotting showed p53 expression had no remarkable changes in honokiol-induced RKO cell apoptosis. LS180 cells treated with honokiol exhibited apparent growth inhibition like RKO ceils and Sw480 ceils.CONCLUSION: Honokiol can induce RKO cells apoptosis through activating caspase cascade by p53-indepenent pathway.
基金Supported by Cheung Kong Scholars Programme of National Ministry of Education,China,and Li Ka Shing Foundation,Hong Kong Co-first-authors: Fei Chen and Tao Wang
文摘AIM: To investigate the anticancer activity of Honokiol on RKO,a human colorectal carcinoma cell line in vitro and in vivo,and to evaluate its possible use in clinic.METHODS: In vitro anticancer activity of honokiol was demonstrated by its induction of apoptosis in tumor cells.We analyzed cell proliferation with MTT assay, cell cycle with flow cytosmeter, DNA fragment with electrophoresis on agarose gels. To test the mechanism of honokiol-induced apoptosis, Westem blotting was used to investigate the factors involved in this process. The pharmacokinetics study of honokiol was tested by high phase liquid chromatography.In in vivo study, Balb/c nude mice were incubated with RKO cells. Honokiol was injected intraperitoneally every other day into tumor bearing Balb/c nude mice.RESULTS: Our results showed that honokiol induced apoptosis of RKO cells in a time- and dose-dependent manner. At 5-10 ug/mL for 48 h, honokiol induced apoptosis through activating Caspase cascades. Pharmacokinetics study demonstrated that, honokiol could be absorbed quickly by intraperitoneal injection, and maintained in plasma for more than 10 h. In nude mice bearing RKO-incubated tumor, honokiol displayed anticancer activity by inhibiting tumor growth and prolonging the lifespan of tumor bearing mice.CONCLUSION: With its few toxicity to normal cells and potent anticancer activity in vitroand in vivo, honokiol might be a potential chemotherapy candidate in treating human colorectal carcinoma.