KB VCR R

KB/VCR is a vincristine-resistant, P-glycoprotein-expressing derivative of the KB human cancer cell lineage used to study multidrug resistance[1-3]. Compared with parental KB cells, KB/VCR cells show reduced intracellular drug accumulation, enhanced efflux, and resistance that can be reversed by compounds that inhibit P-glycoprotein function or expression, restoring vincristine-induced apoptosis and cell-cycle arrest^[2][3]. Although recent papers often describe KB/VCR as an oral-cancer model, the parental KB lineage was historically implicated in HeLa contamination^[1], so experimental oral-cancer labeling should not be conflated with verified donor origin; applications include transporter assays, chemosensitizer screening, and resistance-mechanism studies.