Abstract 3634: Overexpression of PLK1 activates IL4/JAK/STAT6 signaling in prostatic tumor-microenvironment

Abstract

Abstract The correlation between PLK1 expressions with prostate cancer (PCa) stages was identified by analyzing the transcriptome profile of PLK1 in patients from the Cancer Genome Atlas (TCGA) database, and scoring the protein expression in a clinical tissue microarray (TMA) cohort. Integrating our prostate-specific PLK1 knock-in mouse model, we established an oncogenic role for PLK1 in PCa progression. To elucidate the underlying mechanism, we investigated the impact of PLK1 overexpression on prostatic tumor microenvironment (TME) in vivo. In addition, in vitro co-culture systems with both epithelial cells and macrophages were designed to uncover the regulatory function of PLK1 in macrophage polarization. We found that PLK1 induces phosphorylation of JAK3, activates the JAK/STAT6 pathway in cancer cells, and increases the secretion of IL4, which enables macrophage polarization towards the M2 phenotype in TME—ultimately accelerating PCa development. Finally, pharmaceutical inhibition of STAT6 signaling significantly reverses the PLK1-mediated M2 polarization and, subsequently, inhibits the progression of PCa. Our findings provide clinical and pre-clinical evidence to characterize the role of PLK1 in promoting PCa and novel insights into the regulatory mechanism of PLK1 in the TME. We also provide strong support for the clinical potential of targeting STAT6 for advanced PCa therapy. Citation Format: Ruixin Wang, Xiaoqi Liu. Overexpression of PLK1 activates IL4/JAK/STAT6 signaling in prostatic tumor-microenvironment. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 3634.