AS mRNA and protein expression in ASshRNA-tranduced MCF-7 cells. MCF-7 was transduced with ASshRNA delivered by lentiviruses for generation of stable AS-shRNA expression cell lines. After 15 passages of subculture, total RNA and protein were extracted from the cells. AS mRNA level was evaluated by PCR (a) and endogenous AS protein expression was determined by Western blotting (b). Unt represents untransduced MCF-7; EGFP: EGFP-transduced MCF-7; and ASshRNA: ASshRNA-transduced MCF-7.