RESUMO
Aim To investigate the effect of gelsemium alkaloids on chloride channels and cell volume in he-patic carcinoma cells. Methods The time-lapse live cell imaging and whole-cell patch clamp techniques were used respectively to detect the volume changes and currents induced by gelsemium alkaloids in HepG2 cells. Results It was found that the cell volume was decreased by (12. 48 ± 2. 2) % (P<0. 01) when ex-posed to gelsemium alkaloids for 50 min and this phe-nomenon could be inhibited by the chloride channel blocker tamoxifen. It was shown by whole-cell patch clamping that a chloride current could be evoked by extracellular application of gelsemium alkaloids ( 2μmol·L-1 ) . The current was outward-rectified with-out obvious voltage- and time-dependent inactivation. The reversal potential of the current was ( -3. 21 ± 0. 67) mV ,which was close to the equilibrium poten-tial of chloride. The extracellular application of the chloride blockers, tamoxifen and 5-notro-2-(3-phenyl-propylamino)benzoic acid (NPPB), and 47% hyper-tonic solution inhibited the current significantly ( P <0. 01 ) . Conclusion Gelsemium alkaloids could acti-vate chloride channels and induce a volume decrease ( named apoptotic volume decrease, AVD) , and these effect could be inhibited by chloride channel blockers. The results suggest that the chloride channel can be one of the targets of gelsemium alkaloids in their anti-cancer action.
RESUMO
Aim To establish a hepatic carcinoma cell line with stable voltage-gated chloride channel 3 ( ClC-3 ) gene silencing through the lentivirus-mediated short-hairpin RNA ( shRNA ) method and investigate the effects of gene silencing on invasion and migration. Methods Three lentiviral vectors coding shRNA tar-geting ClC-3 gene were constructed, the recombinant plasmids were packaged into mature lentivirus by 293FT cells, and then the lentiviruses were harvested, concentrated and titrated. MHCC97H cells were infec-ted with the recombinant lentiviruses and then were se-lected to obtain cell lines stably expressing ClC-3 shR-NA. The efficiency of ClC-3 mRNA and protein ex-pression interference were determined by real-time flu-orescence quantitative PCR and Western blot, respec-tively. The effects of ClC-3 gene interference on inva-sion and migration of MHCC97 H cells were performed by Transwell chamber assays with or without Matrigel and cell scratch assay. Results The recombinant lentiviral vectors were successfully constructed and four lentiviruses were acquired after packaged by 293 FT cells. One negative control cell line and three cell lines with ClC-3 gene interference ( MHCC97 H/shClC-3-1 , shClC-3-2 and shClC-3-3 ) were successfully construc-ted after MHCC97 H cells were infected with lentivirus-es. The expression level of ClC-3 mRNA and protein in three ClC-3-silenced cells were obviously lower than the negative control cells ( P <0. 01 ) , MHCC97 H/shClC-3-2 cells showed the greatest inhibition of ClC-3 mRNA and protein expressions. As compared with the negative control cells, the ClC-3 gene interference sig-nificantly decreased invasion and migration of MH-CC97 H cells in vitro ( P <0. 01 ) . Conclusion The hepatic carcinoma cell lines with stable ClC-3 gene si-lencing were successfully established and the ClC-3 gene interference could significantly inhibit invasion and migration of MHCC97H cells.