The mechanism of the role of ABC transporters in the multi-drug resistance of SP cells in SPC-A1 cell lines / 医学研究生学报

ABSTRACT

Objective: Recent researches suggest that tumors are organized in a hierarchy of heterogeneous cell populations and that the capability of maintaining tumor formation/growth specifically resides in a small population of cells called cancer stem cells(CSCs).CSCs are resistant to traditional cancer chemotherapy and radiation therapy because they highly express ATP-binding cassette(ABC) drug transporters and are relatively quiescent,with higher DNA repair and anti-apoptosis abilities.The purpose of this study is to investigate the relationship of ABC transporters with the multi-drug resistance and cancer stem cells of SPC-A1 cell lines.Methods: On the basis of Docetaxel-resistant cell line-SPC-A1/ Docetaxel,we compared the content and biological characteristics of SP cells,the expression of ABC transporters and its effect on the multi-resistance to Docetaxel between SPC-A1 and SPC-A1/ Docetaxel cell lines.Results: SP cells existed in both the SPC-A1 and the SPC-A1/ Docetaxel cell line,with a higher content in the latter.P-gp and BCRP obviously expressed in the SPC-A1/ Docetaxel and SPC-A1/ Docetaxel-SP cells,but only the expression of BCRP was increased in SPC-A1-SP cells.SPC-A1-SP cells also showed obviously higher abilities of proliferation,cloning and tumor formation than SPC-A1/ Docetaxel-SP cells.The multi-drug resistance of SPC-A1/ Docetaxel cells could be reversed with verapamil,but their resistance to Docetaxel could not be reversed completely with the same concentration of the drug.Conclusion: BCRP plays a major role in separating SP cells with tumor stem cell traits and its expression counts for the multi-drug resistance of SPC-A1-SP cells.