Breast cancer resistance protein (Bcrp) an. The testis - An unexpected turn of events

Abstract

Breast cancer resistance protein (Bcrp) is an ATP-dependent efflux drug transporter. It has a diverse spectrum of hydrophilic and hydrophobic substrates ranging from anticancer, antiviral and antihypertensive drugs, to organic anions, antibiotics, phytoestrogens (e.g., genistein, daidzein, coumestrol), xenoestrogens and steroids (e.g., dehydroepiandrosterone sulfate). Bcrp is an integral membrane protein in cancer and normal cells within multiple organs (e.g., brain, placenta, intestine and testis) that maintains cellular homeostasis by extruding drugs and harmful substances fro. The inside of cells. I. The brain, Bcrp is a major component o. The blood-brain barrier located on endothelial cells near tight junctions (TJs). However, Bcrp is absent a. The Sertoli cell blood-testis barrier (BTB); instead, it is localized almost exclusively t. The endothelial TJ in microvessels i. The interstitium an. The peritubular myoid cells i. The tunica propria. Recent studies have shown that Bcrp is also expressed stage specifically and spatiotemporally by Sertoli and germ cells i. The seminiferous epithelium of rat testes, limited only to a testis-specific cell adhesion ultrastructure known a. The apical ectoplasmic specialisation (ES) in stage VI-early VIII tubules. These findings suggest that Bcrp is equipped by late spermatids and Sertoli cells to protect late-stage spermatids completing spermiogenesis. Furthermore, Bcrp was found to be associated with F (filamentous)-actin and several actin regulatory proteins a. The apical ES and might be involved i. The organisation of actin filaments a. The apical ES in stage VII-VIII tubules. These findings will be carefully evaluated in this brief review.