Knockdown of PSCA induces EMT and decreases metastatic potentials of the human prostate cancer DU145 cells

Ran Kang; Shankun Zhao; Luhao Liu; Futian Li; Ermao Li; Lianmin Luo; Lihua Xu; ShawPong Wan; Zhigang Zhao

doi:10.1186/s12935-016-0295-4

Knockdown of PSCA induces EMT and decreases metastatic potentials of the human prostate cancer DU145 cells

Cancer Cell Int. 2016 Mar 15:16:20. doi: 10.1186/s12935-016-0295-4. eCollection 2016.

Authors

Ran Kang^#¹, Shankun Zhao^#¹, Luhao Liu^#¹, Futian Li¹, Ermao Li¹, Lianmin Luo¹, Lihua Xu², ShawPong Wan¹, Zhigang Zhao¹

Affiliations

¹ Department of Urology & Andrology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical University, Guangdong Provincial Key Laboratory of Urology, No.1-3, Kangda Road, Guangzhou, 510230 Guangdong Province China.
² Department of Hematology, The First Affiliated Hospital of Guangzhou Medical University, Guangzhou, 510230 China.

^# Contributed equally.

Abstract

Background: Prostate stem cell antigen (PSCA) expression has been shown to correlate with prostatic carcinogenesis and prostate cancer (PCa) progression. The underlying mechanisms for these processes are currently unknown. Epithelial to mesenchymal transition (EMT) has been associated with the invasiveness and the distant metastasis of PCa. In this study, we investigated the effects of knocking down the PSCA on the cell migration, the invasiveness, and the EMT of the PCa cell line DU145 in vitro and in vivo.

Methods: Four target sequences of the small hairpin RNA for PSCA were designed, and the best effect knockdown sequence shRNA#1 was screened to construct the stable transfected DU145 cell line (DU145 shRNA#1), the scramble sequence was also designed to construct the stable transfected DU145 cell line(DU145 scramble). Cell migration and invasion were studied using Transwell assay. Quantitative RT-PCR, Western blot (WB) were used to quantify PSCA, E-cadherin, β-catenin, Vimentin, Fibronectin expression in DU145, DU145 scramble, DU145 shRNA#1 in vitro and in vivo. RT-PCR, immunofluorescent staining were used to quantify PSCA, E-cadherin, and Vimentin expression in vitro. EMT-related genes Snail, Slug, and Twist, were quantified by quantitative RT-PCR in vitro.

Results: The constructed stable knockdown of the PSCA in the DU145 cell had a silencing effect up to 90.5 %. DU145 shRNA#1 became scattered from the tightly packed colonies. It was associated with decreased cell migration and invasion. There was also an increased Vimentin and Fibronectin expression, an inhibited E-cadherin and β-catenin expression at both the mRNA and the protein levels when compared to the DU145 and the DU145 scramble in vitro and vivo. Furthermore, with the exception of the Snail, the expression of EMT-related Slug and Twist genes were upregulated.

Conclusions: Our data indicated that knockdown of PSCA induced EMT and reduced metastatic potentials of the DU145 cells, suggesting that PSCA played an important role in prostatic carcinogenesis and progression.

Keywords: Epithelial-mesenchymal transition; Metastasis; Prostate cancer; Prostate stem cell antigen.