Unknown,Transcriptomics,Genomics,Proteomics

Dataset Information

PITX1 suppresses TERT transcription

ABSTRACT: Using microcell-mediated chromosome transfer (MMCT) into the mouse melanoma cell line, B16F10, we have previously found that human chromosome 5 carries a gene, or genes, that can negatively regulate TERT expression. To identify the gene responsible for the regulation of TERT transcription, we performed cDNA microarray analysis using parental B16F10 cells, telomerase negative B16F10 microcell hybrids with a human chromosome 5 (B16F10MH5), and its revertant clones (MH5R) with reactivated telomerase. Here we report the identification of PITX1, whose restoration leads to the downregulation of mouse tert (mtert) transcription, as a TERT suppressor gene. Additionally, both human TERT (hTERT) and mouse TERT (mtert) promoter activity can be suppressed by PITX1. We showed that three and one binding sites, respectively, within the hTERT and mtert promoters that express a unique conserved region are responsible for the transcriptional activation of TERT. Furthermore, we showed that PITX1 binds to the TERT promoter both in vitro and in vivo. Thus, PITX1 suppresses TERT transcription through direct binding to the TERT promoter, which ultimately regulates telomerase activity. We transferred intact human chromosome 5 into mouse melanoma B16F10 cells by microcell fusion. The microcell hybrids (MH5) exhibited suppression of telomerase, we also obtained revertant clones (MH5R) in which telomerase is reactivated. To identify the differentially expressed genes on human chromosome 5, we performed expression microarray analysis using these two clones and parental B16F10 cells.

ORGANISM(S): Mus musculus

SUBMITTER: hiroyuki kugoh

PROVIDER: E-GEOD-23216 | biostudies-arrayexpress |

REPOSITORIES: biostudies-arrayexpress

ACCESS DATA

Similar Datasets

Project description:Although high-risk human papillomavirus (HPV) infection plays a major role in the development of cervical cancer, additive oncogenic events are involved as well. One key event involves increased activity of telomerase resulting from a deregulated expression of its catalytic subunit hTERT. Our previous microcell-mediated chromosome transfer studies revealed that introduction of human chromosome 6 in the HPV16 immortalized keratinocyte cell line FK16A and in the HPV16 containing cervical cancer cell line SiHa induced growth arrest, resulting from a repression of hTERT mRNA expression and telomerase activity. Here, this model was used to analyze expression profiles associated with hTERT deregulation in HPV transformed cells. Microarray expression analysis of 12 FK16A/chromosome 6 hybrids, four of which were negative for endogenous hTERT and 8 of which were positive for endogenous hTERT, resulted in the identification of 164 differentially expressed genes. Differential expression of a selection of 5 genes was verified by real-time RT-PCR. Of these 164 genes, 32 were also differentially expressed in other HPV transformed cells with deregulated hTERT. For 2 of these genes, encoding AQP3 and MGP, altered expression in hTERT positive cervical carcinomas was confirmed by real-time RT-PCR and immunohistochemistry, respectively. In summary we identified 32 candidate biomarkers for deregulated hTERT mRNA expression which may enable the identification of cervical premalignant lesions that are at highest risk to progress to invasive cancer. Keywords: microarray expression analysis, hTERT, cervical cancer 12 previously established cell hybrids, all carrying the same genetic background were subjected to microarray expression analysis. These hybrids were generated by the introduction of chromosome 6 in the HPV16 immortalized cell line FK16A, which resulted in a suppression of hTERT expression and telomerase activity. 8 hybrids were endogenous hTERT positive and 8 hybrids were hTERT negative. Additionally primary keratinocytes (hTERT negative), parental cell line FK16A and cervical cancer cell line SiHa (both hTERT positive) were hybridized.

Dataset Information

PITX1 suppresses TERT transcription

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets