Brief Article
Copyright ©2009 The WJG Press and Baishideng. All rights reserved.
World J Gastroenterol. Mar 14, 2009; 15(10): 1259-1263
Published online Mar 14, 2009. doi: 10.3748/wjg.15.1259
Antisense expression of PKCα improved sensitivity of SGC7901/VCR cells to doxorubicin
Da-Long Wu, Feng-Ying Sui, Cheng Du, Cheng-Wen Zhang, Bin Hui, Shui-Ling Xu, Huan-Zhang Lu, Guo-Jie Song
Da-Long Wu, Feng-Ying Sui, Cheng-Wen Zhang, Bin Hui, Guo-Jie Song, Department of Pharmacology, School of Medicine, Jiaxing College, Jiaxing 314001, Zhejiang Province, China
Cheng Du, Traditional Chinese Medicine Hospital of Jiaxing City, Jiaxing 314001, Zhejiang Province, China
Shui-Ling Xu, Department of Microbiology, School of Medicine, Jiaxing College, Jiaxing 314001, Zhejiang Province, China
Huan-Zhang Lu, Department of Clinical Pharmacology, Affiliated Hospital, Chinese Academy of Military Medical Sciences, Beijing 100039, China
Author contributions: Wu DL, Zhang CW and Hui B performed the research; Sui FY, Du C, Xu SL and Song GJ gave some advice; Wu DL and Lu HZ designed the research; Wu DL wrote the paper.
Correspondence to: Da-Long Wu, PhD, Associate Professor, Department of Pharmacology, School of Medicine, Jiaxing College, Jiaxing 314001, Zhejiang Province, China. wudalong66@sina.com
Telephone: +86-573-83643836
Fax: +86-573-83643497
Received: August 1, 2008
Revised: October 25, 2008
Accepted: November 1, 2008
Published online: March 14, 2009
Abstract

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 PKCα content 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 PKCα protein level was about 8.7-fold higher in SGC7901/VCR cells than that in SGC7901 cells, whereas the protein expression of PKCα was 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: PKCα positively regulates MDR in SGC7901 cells, and inhibition of PKCα can partially attenuate MDR in human gastric cancer cells.

Keywords: Multi-drug resistance; Protein kinase C alpha; SGC7901; Gastric cancer