Detection of P-glycoprotein in solid tumors by flow cytometry
Fujii, H.; Tanigawa, N.; Muraoka, R.; Shimomatsuya, T.; Tanaka, T.
Anticancer Research 13(6a): 2171-2175
1993
ISSN/ISBN: 0250-7005 PMID: 7905253 Document Number: 418295
P-glycoprotein (P-gp) detection by FCM (flow cytometry) was correlated with P-gp detection by immunohistochemical staining or Western blotting in K562 cell lines variably resistant to doxorubicin (DOX). A strong correlation was noted between the flow cytometric data and the degree of resistance assessed by thymidine incorporation assay (TIA). Of the human carcinomas tested, 37.5% were P-gp positive by flow cytometry. The flow cytometry data correlated strongly with the immunohistochemical staining (p < 0.001). Thirteen of the 15 P-gp positive tumors were resistant to DOX and vincristine (VCR) on TIA. Thus, P-gp detection by FCM correlates strongly with tumor sensitivity to DOX and VCR (p < 0.001).