Lin28 expression in breast cancer cell lines and the transfection efficiencies of the Lin28-siRNAs, Lin28-expressing plasmid and Lin28-mutant plasmid.
A. Differential expression of Lin28 was analyzed by Western blotting in multiple breast cell lines, including MCF-7, SK-3rd, MCF-10A, MDA-MB-231 and BT-474. B. Western blotting showed that transient transfection of either of the Lin28-siRNAs in MDA-MB-231 cells, compared with GFP-siRNA transfection, led to a reduction in the expression of Lin28. C and D. Lin28 expression was determined by PCR (C) and Western blotting (D) in MCF-7 cells that were stably transfected with pc-Lin28-1, pc-Lin28-2 (C and D) or Lin28-mut (D). GAPDH was used as a loading control.