In order to compare the activity of these two HSPBs expressed in BC cells, we analysed whether HSPB1 downregulation recapitulates the modification we described after HSPB8 silencing: To this aim, we produced a siRNA directed against HSPB1 and transfected MCF-7 cells to evaluate HSPB1 protein levels. The gene discussed is HSPB8; the disease is breast cancer.