SBSN drives bladder cancer metastasis via EGFR/SRC/STAT3 signalling

Br J Cancer. 2022 Jul;127(2):211-222. doi: 10.1038/s41416-022-01794-7. Epub 2022 Apr 28.

Abstract

Background: Patients with metastatic bladder cancer have very poor prognosis and predictive biomarkers are urgently needed for early clinical detection and intervention. In this study, we evaluate the effect and mechanism of Suprabasin (SBSN) on bladder cancer metastasis.

Methods: A tissue array was used to detect SBSN expression by immunohistochemistry. A tumour-bearing mouse model was used for metastasis evaluation in vivo. Transwell and wound-healing assays were used for in vitro evaluation of migration and invasion. Comprehensive molecular screening was achieved by western blotting, immunofluorescence, luciferase reporter assay, and ELISA.

Results: SBSN was found markedly overexpressed in bladder cancer, and indicated poor prognosis of patients. SBSN promoted invasion and metastasis of bladder cancer cells both in vivo and in vitro. The secreted SBSN exhibited identical biological function and regulation in bladder cancer metastasis, and the interaction of secreted SBSN and EGFR could play an essential role in activating the signalling in which SBSN enhanced the phosphorylation of EGFR and SRC kinase, followed with phosphorylation and nuclear location of STAT3.

Conclusions: Our findings highlight that SBSN, and secreted SBSN, promote bladder cancer metastasis through activation of EGFR/SRC/STAT3 pathway and identify SBSN as a potential diagnostic and therapeutic target for bladder cancer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, Differentiation / metabolism*
  • Cell Line, Tumor
  • Cell Movement
  • ErbB Receptors / genetics
  • ErbB Receptors / metabolism
  • Gene Expression Regulation, Neoplastic
  • Mice
  • Neoplasm Metastasis
  • Prognosis
  • Proto-Oncogene Proteins pp60(c-src) / metabolism
  • Signal Transduction
  • Urinary Bladder Neoplasms* / pathology
  • src-Family Kinases / metabolism

Substances

  • Antigens, Differentiation
  • suprabasin protein, mouse
  • ErbB Receptors
  • Proto-Oncogene Proteins pp60(c-src)
  • src-Family Kinases