CCN5/WISP-2 promotes growth arrest of triple-negative breast cancer cells through accumulation and trafficking of p27Kip1 via Skp2 and FOXO3a regulation

Abstract

The matricellular protein CCN5/WISP-2 represents a promising target in triple-negative breast cancer (TNBC) because treatment or induced activation of CCN5 in TNBC cells promotes cell growth arrest at the G0/G1 phase, reduces cell proliferation and delays tumor growth in the xenograft model. Our studies found that the p27(Kip1) tumor suppressor protein is upregulated and relocalized to the nucleus from cytoplasm by CCN5 in these cells and that these two events (upregulation and relocalization of p27(Kip1)) are critical for CCN5-induced growth inhibition of TNBC cells. In the absence of CCN5, p27(Kip1) resides mostly in the cytoplasm, which is associated with the aggressive nature of cancer cells. Mechanistically, CCN5 inhibits Skp2 expression, which seems to stabilize the p27(Kip1) protein in these cells. On the other hand, CCN5 also recruits FOXO3a to mediate the transcriptional regulation of p27(Kip1). The recruitment of FOXO3a is achieved by the induction of its expression and activity through shifting from cytoplasm to the nucleus. Our data indicate that CCN5 blocks PI3K/AKT signaling to dephosphorylate at S318, S253 and Thr32 in FOXO3a for nuclear relocalization and activation of FOXO3a. Moreover, inhibition of α6β1 receptors diminishes CCN5 action on p27(Kip1) in TNBC cells. Collectively, these data suggest that CCN5 effectively inhibits TNBC growth through the accumulation and trafficking of p27(Kip1) via Skp2 and FOXO3a regulation, and thus, activation of CCN5 may have the therapeutic potential to kill TNBC.

Deficiency of CCN5/WISP-2-Driven Program in breast cancer Promotes Cancer Epithelial cells to mesenchymal stem cells and Breast Cancer growth

“…In addition, hrCCN5 effect was also tested in CCN5-positive MCF-7 cells to provide evidence that hrCCN5 has no effect on the cells that endogenously express CCN5. Consistent with previous work 32 , a significant reduction in proliferation of MDA-MB-231 cells and HCC-70 (Figure S2) were observed in dose dependent manner. Half maximal inhibitory concentration (IC 50 s) of hrCCN5 in both cell lines was 250 ng/ml or high.…”

“…1A and B), we used MDA-MB-231and HCC-70 cell lines as in vitro TNBC model and side-population (SP)-model of MCF-7 cells as a mean to interrogate whether deficiency of CCN5-driven program in BC promotes cancer epithelial cells to mesenchymal stem cells and BC growth. In TNBC model, we found comprehensive pattern of CCN5 effect than that previously reported 24, 31, 32 . CCN5-treatment significantly reduces the TNBC cell growth parallel with induction of apoptosis and Bcl-2/Bax ratio (Fig.…”

“…A required role for CCN5 in inhibition of BC progression is similarly found in SP-MCF-7 model (Figs 4–6) to extend the antitumorigenic role in aggressive BC 24, 25, 32, 44, 45 . We observed that like TNBC cells, ER-α, Her-2 and CCN5 is down regulated in SP cells while MCF-7 as well as NSP of MCF-7 cells are ER-α and CCN5 positive.…”

“…The previous studies have suggested an anti-invasive role of CCN5 in aggressive TNBC cells 24, 29, 31, 32 . While examining the relationship of CCN5 mRNA expression levels and clinical outcome of human BC progression using bioinformatically analyzed (SurvExpress program) multiple published global microarray datasets of BC patients with or without receptors (i.e., ER, PR and HER-2) 33 , we found high expression of CCN5 predicts good prognosis and increase overall patient survival (Fig.…”

Egg antigen p40 of Schistosoma japonicum promotes senescence in activated hepatic stellate cells via SKP2/P27 signaling pathway

“…P27 signaling pathway is served as an important aging-associated signaling pathway 24 . To prove whether the underlying molecular mechanism of Sjp40-induced senescence and cell cycle arrest is associated with P27-related signal pathways, total proteins extracted from LX-2 cells treated with or without Sjp40 were analyzed by Western blot assay with the specific antibodies against P27, P-ERK, SKP2 and P-Rb.…”