Figure 4.

Influence of Musashi (MSI) RNA-binding protein knockdown on DNA protein kinase catalytic subunit (DNA-PKcs) and Epithelial growth factor receptor (EGFR) protein expression as well as radioresistance in triple-negative MDA-MB-231 cells. A: DNA-PKcs expression, as quantified by Western blot, is strongly downregulated after MSI knockdown, with representative blots in (B). C: EGFR expression, as quantified by Western blot, is downregulated after MSI silencing, with representative blots in (D). E: Radioresistance, as quantified by colony formation, is decreased after MSI knockdown and radiation doses of 2, 4 and 6 Gy, respectively, when compared to controls (ctrl). Cells were transfected with a control siRNA and MSI-1 and MSI-2 siRNA, respectively, as detailed in the Methods section (at least n = 3, * p < 0.05, ** p < 0.01, error bars indicate s.e.m.).