FOXM1  modulates docetaxel resistance in prostate cancer by regulating KIF20A

Abstract

Background：Resistance to docetaxel is an important factor which affects the prognosis in advanced prostate cancer (PCa). The precise mechanisms remain unclear. The transcription factor Forkhead box M1 (FOXM1), participating in cell cycle progress and cell proliferation, has been reported to affect the sensitivity of chemotherapy. The present study aims to explore the role of FOXM1 in docetaxel resistance of PCa and how FOXM1 is associated with kinesin family member 20 A (KIF20A), which has been demonstrated to promote the development of therapeutic resistance in some cancers. Methods: We monitored cell growth by MTT and colony formation assays , and cell apoptosis and cell cycle through flow cytometry. Wound-healing and transwell assays were performed to detect cell migration and invasion. The mRNA and protein expression of gene were analyzed by by quantitative reverse transcription polymerase chain reaction (qRT-PCR) and western blotting, respectively. We determined the binding of FOXM1 on the KIF20A promoter by the ChIP assay. Tumorigenicity in nude mice was employed to assess tumorigenicity in vivo. Results: FOXM1 knockdown induced cell apoptosis and G2/M cell cycle arrest, and suppressed cell migration and invasion in docetaxel-resistant PCa cell lines (DU145-DR and VCaP-DR). The opposite trend was found in their parental cells with exogenous FOXM1 overexpression. Furthermore, thiostrepton, a specific inhibitor for FOXM1, significantly attenuated docetaxel resistance in vitro and in vivo. Additionally, we found that FOXM1 and KIF20A were consistently overexpressed and highly correlated in PCa cells and tissues. Further studies demonstrated that FOXM1 regulated the expression of KIF20A at the transcriptional level directly through a Forkhead response element (FHRE) in its promoter. Moreover, KIF20A overexpression could partially reverse the effects of FOXM1 depletion on cell proliferation, cell cycle proteins (cyclinA2, cyclinD1 and cyclinE1) and apoptosis protein (bcl-2 and PARP). Conclusions: our findings suggest that highly expressed FOXM1 may promote docetaxel resistance partly through the induction of KIF20A expression and provide insights into novel chemotherapeutic strategies for docetaxel resistance in PCa.

Identification of candidate biomarkers correlated with poor prognosis of breast cancer based on bioinformatics analysis

“…Some researchers reported that TOP2A could induce apoptosis and suppress cell growth and invasion via AKT/ERK signaling pathways in colon cancer [7]. Kinesin family member 20A (KIF20A) is believed to modulate microtubule dynamics [60], which could promote the tumorigenesis and progression of prostate cancer and glioma [61], particularly the biochemical recurrence and metastasis [60,62]. Silencing KIF20A could induce prostate cancer cells to death and aberrantly activated Gli2-KIF20A axis which is crucial for the growth of hepatocellular carcinoma and predicts poor prognosis in hepatocellular carcinoma [63].…”