CD44 enhances adriamycin resistance in chronic myelogenous leukaemia cells K562

Introduction To investigate CD44 effects on the adriamycin‐resistant in chronic myelogenous leukaemia cells K562, we explored the role of CD44 in the K562 cells migration and apoptosis. Methods GeneChip® screening is used for elucidating various chemoresistance‐related gene expression in the adriamycin‐resistant leukaemia cells K562/ADR. We constructed K562/CD44 cells by transfection of an EGFP‐SV40‐CD44 plasmid, and adriamycin‐resistant ability was confirmed by detecting migration and apoptosis‐related proteins and mRNA expression using Western blotting and Real‐time PCR respectively. Results K562/CD44 cells were generated by the transfection of an EGFP‐SV40‐CD44 plasmid with high CD44 expression. mRNA expression levels of CD44 and P‐glycoprotein (P‐gp), along with the proliferation rate, were increased, while the apoptosis rate of K562/CD44 cells was decreased. Migration‐associated proteins such as MMP‐2 and MMP‐9 were upregulated, whereas apoptosis‐related protein Bax was downregulated and Bcl‐2 protein was not significantly altered in the K562/CD44 cells. Conclusions CD44 might be involved in adriamycin resistance via regulation of P‐gp, MMP‐2, MMP‐9, and Bcl‐2/Bax.