Regulation of the hTERT promoter activity by MSH2, the hnRNPs K and D, and GRHL2 in human oral squamous cell carcinoma cells

Oncogene. 2009 Jan 29;28(4):565-74. doi: 10.1038/onc.2008.404. Epub 2008 Nov 17.


Higher expression of human telomerase reverse transcriptase (hTERT) and subsequent activation of telomerase occur during cellular immortalization and are maintained in cancer cells. To understand the mode of hTERT expression in cancer cells, we identified cancer-specific trans-regulatory proteins that interact with the hTERT promoter, using the promoter magnetic precipitation assay coupled with mass spectrometry. The identified proteins include MutS homolog 2 (MSH2), heterogeneous nuclear ribonucleoprotein (hnRNP) D, hnRNP K and grainyhead-like 2 (GRHL2). We noticed a higher expression of these proteins in human oral squamous cell carcinoma (OSCC) cells than in normal cells, which do not exhibit telomerase activity. Knockdown of MSH2, hnRNP D and GRHL2 resulted in a notable reduction of the hTERT promoter activity in tested cancer cells. Silencing of the above genes resulted in a significant reduction of the telomerase activity in OSCC cells. Interestingly, among the four identified genes, silencing of GRHL2 was essential in reducing telomerase activity and viability of tested cancer cells. These results suggest a possible role of GRHL2 in telomerase activation during cellular immortalization.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Carcinoma, Squamous Cell / genetics
  • Carcinoma, Squamous Cell / metabolism*
  • Carcinoma, Squamous Cell / pathology
  • Cell Line, Tumor
  • Cell Transformation, Neoplastic / genetics
  • Cell Transformation, Neoplastic / metabolism
  • DNA-Binding Proteins / genetics
  • DNA-Binding Proteins / metabolism*
  • Gene Knockdown Techniques
  • Gene Silencing
  • Heterogeneous-Nuclear Ribonucleoprotein D / genetics
  • Heterogeneous-Nuclear Ribonucleoprotein D / metabolism*
  • Heterogeneous-Nuclear Ribonucleoprotein K / genetics
  • Heterogeneous-Nuclear Ribonucleoprotein K / metabolism*
  • Humans
  • Mouth Neoplasms / genetics
  • Mouth Neoplasms / metabolism*
  • MutS Homolog 2 Protein / genetics
  • MutS Homolog 2 Protein / metabolism*
  • Promoter Regions, Genetic*
  • Telomerase / genetics
  • Telomerase / metabolism*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*


  • DNA-Binding Proteins
  • GRHL2 protein, human
  • Heterogeneous-Nuclear Ribonucleoprotein D
  • Heterogeneous-Nuclear Ribonucleoprotein K
  • Transcription Factors
  • TERT protein, human
  • Telomerase
  • MSH2 protein, human
  • MutS Homolog 2 Protein