Pyr3 inhibits cell viability and PKCα activity to suppress migration in human bladder cancer cells

Eur J Pharmacol. 2025 Feb 5:988:177235. doi: 10.1016/j.ejphar.2024.177235. Epub 2024 Dec 24.

Abstract

Bladder cancer, more prevalent in men, has high recurrence rates in non-muscle-invasive forms and is highly lethal upon metastasis in muscle-invasive cases. Transient receptor potential canonical channels (TRPCs), specifically TRPC3, play a role in calcium signaling, influencing cancer cell behavior. This study examines the effects of Pyr3, a TRPC3 inhibitor, and TRPC3 knockdown on both muscle-invasive (T24) and non-muscle-invasive (RT4) bladder cancer cells. Pyr3 treatment reduced cell viability, migration, adhesion, and calcium influx in these cells. Additionally, Pyr3 treatment and siTRPC3 downregulated protein kinase C alpha (PKCα), phospho-PKCα, and protein phosphatase 2A (PP2A) levels. While PKC activator phorbol 12-myristate 13-acetate (PMA) could not restore Pyr3-induced viability loss, it reversed the migration inhibition. In a xenograft model, Pyr3 suppressed T24 cell viability, Ki67, phospho-PKCα, PP2A and TRPC3 expression. These findings suggest that Pyr3 inhibits bladder cancer cell migration through PKC signaling and holds potential as a therapeutic agent for bladder cancer.

Keywords: Bladder cancer; Migration; PKCα; Pyr3; TRPC3.

MeSH terms

  • Animals
  • Antineoplastic Agents* / pharmacology
  • Cell Line, Tumor
  • Cell Movement* / drug effects
  • Cell Survival / drug effects
  • Humans
  • Mice
  • Protein Kinase C-alpha* / metabolism
  • Protein Phosphatase 2 / metabolism
  • TRPC Cation Channels / antagonists & inhibitors
  • TRPC Cation Channels / genetics
  • TRPC Cation Channels / metabolism
  • Urinary Bladder Neoplasms* / drug therapy
  • Urinary Bladder Neoplasms* / pathology
  • Xenograft Model Antitumor Assays

Substances

  • Protein Kinase C-alpha
  • TRPC Cation Channels
  • TRPC3 cation channel
  • Antineoplastic Agents
  • Protein Phosphatase 2
  • PRKCA protein, human