The novel MKL target gene myoferlin modulates expansion and senescence of hepatocellular carcinoma

Oncogene. 2017 Jun 15;36(24):3464-3476. doi: 10.1038/onc.2016.496. Epub 2017 Jan 23.

Abstract

Megakaryoblastic Leukemia 1 and 2 (MKL1/2) are transcriptional coactivators of Serum Response Factor (SRF) with an essential role for hepatocellular carcinoma (HCC) growth and oncogene-induced senescence. In this report, we identified myoferlin as a novel MKL/SRF target gene by gene expression profiling and verification in vivo in HCC xenografts. Myoferlin was overexpressed in human and murine HCCs triggered by conditional expression of constitutively active SRF-VP16 protein in hepatocytes. Furthermore, myoferlin was required for HCC cell invasion, proliferation and anchorage-independent cell growth. We provide evidence that myoferlin is a crucial gene target of MKL1/2 mediating its effect on oncogene-induced senescence by modulating the activation state of the EGFR and downstream MAPK and p16-/Rb pathways. Depletion of myoferlin in tumour cells from SRF-VP16-derived murine HCCs induced a senescence phenotype. These findings identify MKL1/2 and myoferlin as novel therapeutic targets to treat human HCC by a senescence-inducing strategy.

MeSH terms

  • Animals
  • Calcium-Binding Proteins / genetics
  • Calcium-Binding Proteins / metabolism*
  • Carcinoma, Hepatocellular / genetics
  • Carcinoma, Hepatocellular / metabolism*
  • Cell Line, Tumor
  • Cell Proliferation
  • Gene Expression Profiling / methods*
  • Gene Expression Regulation, Neoplastic
  • Humans
  • Liver Neoplasms / genetics
  • Liver Neoplasms / metabolism*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mice
  • Muscle Proteins / genetics
  • Muscle Proteins / metabolism*
  • NIH 3T3 Cells
  • Neoplasm Invasiveness
  • Neoplasm Transplantation
  • Serum Response Factor / metabolism*
  • Trans-Activators / metabolism*
  • Transcription Factors / metabolism*

Substances

  • Calcium-Binding Proteins
  • MRTFA protein, human
  • MRTFB protein, human
  • MYOF protein, human
  • Membrane Proteins
  • Muscle Proteins
  • SRF protein, human
  • Serum Response Factor
  • Trans-Activators
  • Transcription Factors