The Discovery of SWI/SNF Chromatin Remodeling Activity as a Novel and Targetable Dependency in Uveal Melanoma

Mol Cancer Ther. 2020 Oct;19(10):2186-2195. doi: 10.1158/1535-7163.MCT-19-1013. Epub 2020 Aug 3.

Abstract

Uveal melanoma is a rare and aggressive cancer that originates in the eye. Currently, there are no approved targeted therapies and very few effective treatments for this cancer. Although activating mutations in the G protein alpha subunits, GNAQ and GNA11, are key genetic drivers of the disease, few additional drug targets have been identified. Recently, studies have identified context-specific roles for the mammalian SWI/SNF chromatin remodeling complexes (also known as BAF/PBAF) in various cancer lineages. Here, we find evidence that the SWI/SNF complex is essential through analysis of functional genomics screens and further validation in a panel of uveal melanoma cell lines using both genetic tools and small-molecule inhibitors of SWI/SNF. In addition, we describe a functional relationship between the SWI/SNF complex and the melanocyte lineage-specific transcription factor Microphthalmia-associated Transcription Factor, suggesting that these two factors cooperate to drive a transcriptional program essential for uveal melanoma cell survival. These studies highlight a critical role for SWI/SNF in uveal melanoma, and demonstrate a novel path toward the treatment of this cancer.

MeSH terms

  • Animals
  • Cell Line, Tumor
  • Chromatin / metabolism*
  • Chromosomal Proteins, Non-Histone
  • Humans
  • Melanoma / genetics*
  • Mice
  • Transcription Factors
  • Uveal Neoplasms / genetics*

Substances

  • Chromatin
  • Chromosomal Proteins, Non-Histone
  • SWI-SNF-B chromatin-remodeling complex
  • Transcription Factors

Supplementary concepts

  • Uveal melanoma