论文部分内容阅读
AIM:To explore whether antisense blocking of protein kinase C alpha(PKCα)would reverse multi-drug resistance(MDR)in the vincristine(VCR)-resistant human gastric cancer cell line SGC7901/VCR. METHODS:SGC7901/VCR cells expressing antisense PKCα,SGC7901/VCR/aPKC,were established by transfection with a recombinant plasmid reversely inserted with PKCαcDNA.Empty vector(PCI-neo)transfected cell clones,SGC7901/VCR/neo,served as the control.Western blot method was used to detect PKCαcontent in SGC7901,SGC7901/VCR,SGC7901/ VCR/neo and SGC7901/VCR/aPKC cells,using PKCα-specific antibody.The sensitivity of SGC7901,SGC7901/ VCR,SGC7901/VCR/neo and SGC7901/VCR/aPKC cells to doxorubicin(DOX)in vitro was determined by MTT assay.The uptake of DOX in these cells was detected with fluorescence spectrophotometer.RESULTS:Western blot analysis showed that the PKCαprotein level was about 8.7-fold higher in SGC7901/ VCR cells than that in SGC7901 cells,whereas the protein expression of PKCαwas reduced by 78%in SGC7901/VCR/aPKC cells when compared with the SGC7901/VCR cells.SGC7901/VCR/aPKC cells had a 4.2-fold increase in DOX cytotoxicity,accompanied by a 1.7-fold increase of DOX accumulation in comparison with SGC7901/VCR cells. CONCLUSION:PKCαpositively regulates MDR in SGC7901 cells,and inhibition of PKCαcan partially attenuate MDR in human gastric cancer cells.
AIM: To explore whether antisense blocking of protein kinase C alpha (PKCα) would reverse multi-drug resistance (MDR) in the vincristine (VCR) -resistant human gastric cancer cell line SGC7901 / VCR. METHODS: SGC7901 / VCR cells expressing antisense PKCα , SGC7901 / VCR / aPKC, were established by transfection with a recombinant plasmid reversely inserted with PKCα cDNA. Empty vector (PCI-neo) transfected cell clones, SGC7901 / VCR / neo, served as the control. Western blot method was used to detect PKCαcontent in SGC7901, SGC7901 / VCR, SGC7901 / VCR / neo and SGC7901 / VCR / aPKC cells using PKC α-specific antibody. sensitivity of SGC7901, SGC7901 / VCR, SGC7901 / VCR / neo and SGC7901 / VCR / aPKC cells to doxorubicin DOX) in vitro was determined by MTT assay. The uptake of DOX in these cells was detected with fluorescence spectrophotometer .RESULTS: Western blot analysis showed that the PKCαprotein level was about 8.7-fold higher in SGC7901 / VCR cells than that in SGC7901 cells, while the protein expression of PKCαwas reduced by 78% in SGC7901 / VCR / aPKC cells when compared with the SGC7901 / VCR cells. SGC7901 / VCR / aPKC cells had a 4.2-fold increase in DOX cytotoxicity accompanied by a 1.7-fold increase of DOX accumulation in comparison with SGC7901 / VCR cells. CONCLUSION: PKCαpositively regulates MDR in SGC7901 cells, and inhibition of PKCαcan partially attenuated MDR in human gastric cancer cells.