USP10 promotes pancreatic ductal adenocarcinoma progression by attenuating FOXC1 protein degradation to activate the WNT signaling pathway

Increasing evidence has suggested that ubiquitin-specific protease 10 (USP10), a deubiquitinating enzyme, plays an essential role in targeted protein degradation and participates in cancer progression. However, the relationship between USP10 and pancreatic ductal adenocarcinoma (PDAC) is poorly understood. Here, we developed a USP-targeting siRNA library, combining a loss-of-function experimental screen in patient-derived PDAC cells. This approach identified USP10 as a master regulator of PDAC cell migration. High USP10 expression levels were observed in PDAC patient tissues, which were associated with poor prognosis. Furthermore, knockdown of USP10 expression inhibited PDAC cell proliferation and migration in vivo and in vitro. Mechanistically, USP10 increased FOXC1 protein stability via deubiquitination. The phosphorylation of FOXC1 at S272A was dependent on USP10-mediated deubiquitination of FOXC1. Additionally, USP10 promoted FOXC1 protein localization in the nucleus. Interestingly, FOXC1 could increase USP10 mRNA expression levels by transcriptional activation. Our data suggest that a positive feedback loop exists between USP10 and FOXC1 that can activate WNT signaling, thus facilitating PDAC malignant progression. Therefore, USP10 represents an exciting therapeutic target that could support new strategies for treating PDAC.