Caveolin-1 tumor-promoting role in human melanoma

Int J Cancer. 2009 Oct 1;125(7):1514-22. doi: 10.1002/ijc.24451.

Abstract

Caveolin-1 (Cav-1), a member of the caveolin family, regulates caveolae-associated signaling proteins, which are involved in many biological processes, including cancer development. Cav-1 was found to exert a complex and ambiguous role as oncogene or tumor suppressor depending on the cellular microenvironment. Here we investigated Cav-1 expression and function in a panel of melanomas, finding its expression in all the cell lines. The exception was the primary vertical melanoma cell line, WM983A, characterized by the lack of Cav-1, and then utilized as a recipient for Cav-1 gene transduction to address a series of functional studies. The alleged yet controversial role of phospho (Ph)-Cav-1 on cell regulation was also tested by transducing the nonphosphorylatable Cav-1Y14A mutant. Wild-type Cav-1, but not mutated Cav-1Y14A, increased tumorigenicity as indicated by enhanced proliferation, migration, invasion and capacity of forming foci in semisolid medium. Accordingly, Cav-1 silencing inhibited melanoma cell growth reducing some of the typical traits of malignancy. Finally, we detected a secreted fraction of Cav-1 associated with cell released microvesicular particles able to stimulate in vitro anchorage independence, migration and invasion in a paracrine/autocrine fashion and, more important, competent to convey metastatic asset from the donor melanoma to the less aggressive recipient cell line. A direct correlation between Cav-1 levels, the amount of microvesicles released in the culture medium and MMP-9 expression was also observed.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Biomarkers, Tumor / metabolism*
  • Blotting, Western
  • Caveolin 1 / genetics
  • Caveolin 1 / metabolism*
  • Cell Line, Tumor
  • Cell Movement
  • Disease Progression
  • Fluorescent Antibody Technique
  • Gene Expression Regulation, Enzymologic
  • Gene Expression Regulation, Neoplastic
  • Gene Silencing
  • Humans
  • Matrix Metalloproteinase 9 / metabolism
  • Melanoma / metabolism*
  • Melanoma / pathology
  • Neoplasm Invasiveness
  • RNA, Small Interfering / metabolism
  • Reverse Transcriptase Polymerase Chain Reaction
  • Skin Neoplasms / metabolism*
  • Skin Neoplasms / pathology

Substances

  • Biomarkers, Tumor
  • CAV1 protein, human
  • Caveolin 1
  • RNA, Small Interfering
  • Matrix Metalloproteinase 9