Beta 1-integrin-c-Met cooperation reveals an inside-in survival signalling on autophagy-related endomembranes

Nat Commun. 2016 Jun 23:7:11942. doi: 10.1038/ncomms11942.

Abstract

Receptor tyrosine kinases (RTKs) and integrins cooperate to stimulate cell migration and tumour metastasis. Here we report that an integrin influences signalling of an RTK, c-Met, from inside the cell, to promote anchorage-independent cell survival. Thus, c-Met and β1-integrin co-internalize and become progressively recruited on LC3B-positive 'autophagy-related endomembranes' (ARE). In cells growing in suspension, β1-integrin promotes sustained c-Met-dependent ERK1/2 phosphorylation on ARE. This signalling is dependent on ATG5 and Beclin1 but not on ATG13, suggesting ARE belong to a non-canonical autophagy pathway. This β1-integrin-dependent c-Met-sustained signalling on ARE supports anchorage-independent cell survival and growth, tumorigenesis, invasion and lung colonization in vivo. RTK-integrin cooperation has been assumed to occur at the plasma membrane requiring integrin 'inside-out' or 'outside-in' signalling. Our results report a novel mode of integrin-RTK cooperation, which we term 'inside-in signalling'. Targeting integrin signalling in addition to adhesion may have relevance for cancer therapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Autophagy
  • Carcinogenesis
  • Cell Adhesion
  • Cell Line
  • Cell Movement
  • Fibroblasts / metabolism
  • Gene Expression Regulation / drug effects
  • Gene Expression Regulation / physiology
  • Hepatocyte Growth Factor / pharmacology
  • Humans
  • Integrin beta1 / genetics
  • Integrin beta1 / metabolism*
  • Mice
  • Proto-Oncogene Proteins c-met / genetics
  • Proto-Oncogene Proteins c-met / metabolism*
  • Signal Transduction

Substances

  • Integrin beta1
  • Hepatocyte Growth Factor
  • Proto-Oncogene Proteins c-met