Pin1 inhibition strongly affects mouse and human mammary CSCs traits. (A) and (B) Means and standard deviations and P-values are indicated (t-test, n = 3, M4).
A Pin1 inhibition decreases self-renewal of mouse mammary tumor cells. Serial replating of mammospheres (M1–M4) generated from NOP6 cells treated with DMSO or PiB (1.5 μM). Mammosphere formation efficiency (%MFE) was calculated as percentage of mammospheres divided by the number of plated cells.
B Pin1 knockdown decreases self-renewal of human breast cancer cells. Left panel: MFE of MDA-MB-231-pLKO-shPin1 control cells (Ctrl) compared to shPin1 induced cells (DOX) upon serial passages. Right panel: Quantification of Aldh-positive and Aldh-negative cells from control- and shPin1 induced M4, as assessed by FACS.
C Pin1 knockdown affects expression of stem cell markers. Left panel: qRT-PCR of the indicated stemness and EMT marker genes from MDA-MB-231-pLKO-shPin1 quaternary mammospheres (M4) upon shPin1 induction (DOX) with respect to control cells (Ctrl). Standard deviations are indicated, P-values * <0.02 (t-test, n = 3). Right panel: Western Blot analysis of EMT markers of the same cells. Molecular weights Mr(K) are indicated in kDa. Representative microphotographs of M4 are shown, 200 μm scale bar is indicated.