Article

Prognostic value of human telomerase reverse transcriptase gene expression in oral carcinogenesis.

Department of Surgical Sciences, University of Foggia, Foggia, Italy.
International Journal of Oncology (Impact Factor: 3.03). 07/2007; 30(6):1349-57. DOI: 10.3892/ijo.30.6.1349
Source: PubMed

ABSTRACT Human telomerase reverse transcriptase (hTERT) gene expression in resected specimens of oral squamous cell carcinoma (OSCC) and their surrounding tissue, either apparently normal or clearly histologically dysplastic, was evaluated by both real-time RT-PCR and immunohisto-chemical protein analyses. The expression level of hTERT in oral dysplasia and in OSCC was markedly higher than in normal tissues. The correlation between hTERT expression in OSCC and clinico-pathological parameters or survival of OSCC patients was statistically analyzed. Our study demonstrates that there is no significant relationship between hTERT expression and classical clinico-pathological parameters. Interestingly, survival analysis showed both overexpressing cases and lower survival rate in the early stage of OSCC (p=0.03 for immunohistochemistry; p=0.04 for RT real-time PCR). The histological location of hTERT in these tumors has been discussed in the context of the cancer stem cell theory.

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    • "and/or abnormal expression of CDK4/cyclinD1 [18] [20] [36] [37]. OSCCs, like many other carcinomas , maintain telomere length with telomerase activation [21] [22]. Immortality is one of the important characteristics of malignancy and ectopic expression of these genes thus could mimic the events that occur during development of OSCCs. "
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    • "Previous reference to hTERT activity in head and neck cancer has been with respect to OSCC and related mucosal dysplasia. In particular, using RT – PCR expression analysis, Pannone et al (2007) found 66% of OSCC tumours to be overexpressing hTERT by comparison with normal tissues. The hTERT promoter hypermethylation has been implicated in cervical cancer progression while not correlating with down-regulation hTERT expression (Widschwendter et al, 2004; Iliopoulos et al, 2009; Kumari et al, 2009). "
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