The oncolytic avian reovirus p17 protein suppresses invadopodia formation via disruption of TKs5 complexes and oncogenic signaling pathways

Chao-Yu Hsu¹Jyun-Yi Li²Wei-Ru Huang²Tsai-Ling Liao³Hsiao-Wei Wen²Chi-Young Wang²Lon-Fye Lye¹Brent L Nielsen⁴Hung Jen Liu^2*

• ¹Tungs' Taichung MetroHarbor Hospital, Taichung, Taiwan
• ²National Chung Hsing University, Taichung, Taiwan
• ³Taichung Veterans General Hospital, Taichung, Taiwan
• ⁴Brigham Young University, Provo, Utah, United States

Avian reovirus (ARV) is an oncolytic virus that induces autophagy and apoptosis in cancer cells, regulates the immune response, and exposes tumor-associated antigens to the immune system, making it a promising candidate for cancer therapy. In this study, we investigated how the p17 protein of ARV inhibits cancer cell migration and invadopodia formation, both of which are crucial for cancer metastasis. Our findings show that p17 suppresses nucleoporin Tpr, leading to p53 activation and PTEN upregulation, which in turn blocks FAK-Src complex formation and inhibits the Rab40b-PI3K-Akt pathway. Additionally, p17 transcriptionally downregulates TKs5, Nck1, and Rab40b, thereby reducing the formation of TKs5-Nck1 and TKs5-Rab40b complexes, which are essential for invadopodia formation of cancer cell lines (i.e. HeLa and A549). Since invadopodia facilitate cancer cell invasion by degrading the extracellular matrix, p17's ability to inhibit their formation suggests an important antimetastatic role. Furthermore, when cancer cells were co-transfected with mutant PTEN (C124A), TKs5, or Rab40b plasmids, invadopodia formation was restored, confirming that TKs5 and Rab40b are key mediators in overcoming p17's inhibitory effects.Overall, our study demonstrates that ARV p17 inhibits cancer cell migration and invadopodia formation by activating the p53-PTEN pathway and suppressing key signaling complexes (Referred as FAK-Src, Rab40b-PI3K-Akt, TKs5-Nck1, and TKs5-Rab40b). These findings highlight p17's role as a regulator that disrupts key scaffolding 3 complexes essential for invadopodia formation, providing new insights into its potential therapeutic applications in targeting invasive cancer cells.