Seneciphylline induced the autophagy of cervical cancer cells via MEK/ERK1/2 regulation / 中国药科大学学报

@#The purpose of this study was to explore the effects of seneciphylline on the proliferation and autophagy of cervical cancer HeLa and Caski cells and the possible mechanisms of autophagy. MTT assay was used to evaluate the effect of seneciphylline on the proliferation of cervical cancer cells. Immunofluorescence assay was applied to investigate the formation of autophagosomes in GFP-LC3/HeLa and GFP-LC3/Caski cells. The effect of seneciphylline on the expression of autophagy-related proteins was checked by Western blotting. In addition, fluorescence colocation assay was used to detect the fusion of autophagosomes and lysosomes. Human cervical cancer subcutaneous xenografts in nude mice were used to evaluate the effect of seneciphylline on the growth of the tumor in vivo. Results showed that HeLa cells proliferation was inhibited by seneciphylline in a dose- and time- dependent manner. Seneciphylline could induce formation of autophagosomes, increase the expression of LC3-II and decrease the expression of P62, suggesting that seneciphylline induced autophagy in HeLa and Caski cells. Compared with seneciphylline alone, seneciphylline combined with later-stage autophagy inhibitor chloroquine significantly increased the expression of LC3-II and P62. Moreover, and fluorescence colocation assay showed that autophagosomes induced by seneciphylline could colocate with lysosomes, indicating that seneciphylline could induce the complete autophagy flux. Compared with seneciphylline alone, seneciphylline combined with earlier-stage autophagy inhibitor 3MA significantly increased the expression of LC3-II and significantly decreased HeLa and Caski cells viability, suggesting that seneciphylline induced protective autophagy. Compared with seneciphylline alone, seneciphylline combined with MEK inhibitor significantly decreased the expression of P-ERK1/2 and formation of autophagosomes, suggesting that autophagy induced by seneciphylline activated MEK/ERK1/2 signal pathway. In addition, seneciphylline showed a significant inhibitory effect on growth of human cervical cancer cells subcutaneous xenografts.

Inhibitory effect of epigallocatechin gallate on the proliferation of Lewis Lung Cancer mice and A549 and Calu-3 lung cancer cells / 中国药学杂志

OBJECTIVE: To determine the inhibitory effect of EGCG on the Lewis Lung Cancer Model, to compare and preliminary to discuss the mechanism of the inhibitory effect of EGCG on the proliferation of A549 cell line and Calu-3 cell line. METHODS: Observed the inhibitory effect of EGCG on Lewis Lung Cancer in vivo. Compared the inhibitory effect of different dosages of EGCG on Calu-3 and A549 cell lines with WST-8 assay. Observed the opoptosis promotional effect of EGCG on Calu-3 cells. Compared the inhibitory effect of different dosage of EGCG on Calu-3 and A549 cell lines in PI cell number counting assay. RESULTS: EGCG inhibited the proliferation of Lewis Lung Cancer in vivo. Results of WST-8 assay showed that EGCG inhibited the proliferation of Calu-3 cell line in dose-dependent manner. However, A549 cell line showed sign of drug-resistance to EGCG. The inhibitory effect of EGCG on the proliferation of Calu-3 cell line through increasing apoptosis was observed with TUNEL assay. Cell number of Calu-3 was obviously decreased by treating of EGCG, but was not changed in A549 cell line. CONCLUSION: EGCG inhibited proliferation of Lewis Lung Cacer in vivo, and inhibited proliferation of Calu-3 cell line but didn't play the inhibitory role on A549 cell line in vitro. Copyright 2012 by the Chinese Pharmaceutical Association.

Short chain fatty acids affect colon cancer cells proliferation and differentiation / 肠外与肠内营养

Short chain fatty acids(SCFA) are produced in the large bowel of humans by anaerobic bacterial fermentation.The main fermentative substrates are undigested dietary carbohydrates,including nonstarch polysaccharides and resistant starch(RS).SCFA are major organic acids in the lumen of the large intestine.They are preferred energy source for colonocytes.Their effects include enhancement of electrolyte uptake,stimulation of colon epithelial cell proliferation and mucosa growth,modulation of colonic immune function,nutritional support and protection of colon mucosa.Butyric acid can suppress colon neoplasm cell proliferation,induce its apoptosis and differentiation,affect proto-onc genes expression,which suggest that butyrate may be an important agent in cancer treatment.

Monitoring transfected cells without selection agents by using the dual-cassette expression EGFP vectors

Conventional methods of selecting gene transfected cells by toxic agents may yield ambiguous results. It is difficult to determine whether cell death is due to selection agents or gene transfection, owing to the substantial overlap of the time-courses for both effects. Therefore, to determine transfection-induced cell toxicity, the mammalian expression vector pEGFP-N1 (CLONTECH Lab., Palo Alto, CA, USA) has been modified to the dual-cassette expression vectors named pEGFP-Ks by the relocation of its EGFP expression cassette. We have precisely monitored the cells transfected with this vector on our custom culture dishes, thereby bypassing the need for selection agent or fluorescent cell sorting. This is a useful method to screen genes encoding potential toxic or useful proteins without performing undesirable selection agent and also can be used to monitor the transfected cells for various purposes, either the inhibition or proliferation of mammalian cells for applications in biotechnology.

EFFECTS OF SELENIUM, VITAMIN A AND E ON HUMAN BREAST CANCER CELL PROLIFERATION / 营养学报

The study was conducted in vitro with human breast cancer cells BCaP-37, to determine the effects of selenium, vitamin A, vitamin E and a combination of these three nutrients on cell proliferation and cellular nucleic acid content. Selenium as sodium selenite had two phases of effect on cancer cell proliferation: the low concentrations of selenium (less than 5 ?M) stimulated cell growth and increased the cellular nucleic acid content; the high concentrations (more than 5 ?M) depressed cell growth and reduced the cellular nucleic acid content with dose-dependence. Vitamin A acetate inhibited cancer cell growth significantly, but vitamin A acid inhibited to some extent, and was less effective than vitamin A acetate. Vitamin E had less inhibitory effect compared to vitamin A acetate and the inhibitory percentages were lower than 40% in all treatment groups. Combination of selenium (5 ?M) and vitamin E (20mg/L) or selenium and vitamin A acetate (2mg/L), no synergism for the reduction of the contents of cellular nucleic acids (DNA and RNA) were observed. The combination of selenium, vitamin A acetate and vitamin E at such levels reduced cellular DNA and RNA contents obviously; RNA content was significantly lower than any other treatment group and was reduced synergis-tically. It was indicated that the combination of selenium, vitamin A acetate, vitamin E was synergistic for inhibition of cell proliferation. Results also showed the reversible tendency in the inhibition of cell proliferation by combination of these three nutrients. It was suggested that combination of selenium, vitamin A and E might be benificial for the prevention and adjuvant treatment of human breast cancer.