Concerted functions of HDAC1 and microRNA-574-5p repress alternatively spliced ceramide synthase 1 expression in human cancer cells

EMBO Mol Med. 2012 Feb;4(2):78-92. doi: 10.1002/emmm.201100189. Epub 2011 Dec 19.

Abstract

Histone deacetylases (HDACs) and microRNAs (miRs) have pro-survival roles, but the mechanism behind this is unclear. Repression of ceramide synthase 1 (CerS1), altering C(18) -ceramide generation, was linked to drug resistance and metastasis. Here we report that the CerS1 promoter was repressed by HDAC1-dependent inhibition of Sp1 recruitment to two specific GC-boxes spanning the -177 and -139 region. Moreover, an alternatively spliced variant CerS1 mRNA (CerS1-2) was detected mainly in cancer cells or primary tumour tissues compared to controls, which was targeted by miR-574-5p for degradation. A specific 3'UTR-targeting site, localized within the retained intron between exons 6 and 7, was identified, and its mutation, or miR-574-5p knockdown prevented the degradation of CerS1-2 mRNA. Interference with HDAC1 and miR-574-5p reconstituted CerS1-2 expression and C(18) -ceramide generation in multiple human cancer cell lines, which subsequently inhibited proliferation and anchorage-independent growth. Accordingly, knockdown of CerS1 partially protected cancer cells from MS-275/miR-574-5p siRNA-mediated growth inhibition. Thus, these data suggest that the HDAC1/miR-574-5p axis might provide a novel therapeutic target to reconstitute tumour suppressor CerS1/ceramide signalling.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • 3' Untranslated Regions
  • Alternative Splicing
  • Cell Line, Tumor
  • Cell Proliferation
  • Gene Expression Regulation, Neoplastic*
  • Histone Deacetylase 1 / genetics*
  • Humans
  • Membrane Proteins / genetics*
  • Membrane Proteins / metabolism
  • MicroRNAs / genetics*
  • Neoplasms / genetics*
  • Neoplasms / pathology
  • Signal Transduction / genetics
  • Sphingosine N-Acyltransferase / genetics*
  • Sphingosine N-Acyltransferase / metabolism
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism

Substances

  • 3' Untranslated Regions
  • MIRN574 microRNA, human
  • Membrane Proteins
  • MicroRNAs
  • Tumor Suppressor Proteins
  • CERS1 protein, human
  • CERS2 protein, human
  • Sphingosine N-Acyltransferase
  • HDAC1 protein, human
  • Histone Deacetylase 1