Expression of C-Myc mRNA in squamous cell carcinoma of the tongue.

Background: The aim of this study was to evaluate clinical significance of C-myc mRNA in patients with tongue cancer.

Methods: C-myc mRNA expression was studied by RT-PCR in peripheral blood of 25 tongue cancer patients and 24 controls. C-myc protein expression was studied by immunohistochemistry.

Results: In tongue cancer patients, pretherapeutic C-myc mRNA expression was significantly higher as compared to controls. In tumor tissues, a trend of low expression of C-myc mRNA was noted as compared to pretherapeutic blood. The mean pretherapeutic C-myc mRNA level was lower in tobacco-users, in older patients, in keratinizing tumors, in tumors showed lymphocytic infiltration as well as in non-responders as compared to their respective counterparts. C-myc mRNA expression was lower in tumors showed lymphatic permeation and in patients with a habit of tobacco use. Further, low C-myc mRNA expression associated with poor prognosis. C-myc protein expression was noted in 72% of the tumors and an inverse correlation was noted between C-myc protein expression and disease stage. In early stage disease, an inverse correlation was noted while in advanced stage disease, a positive correlation was noted.

Conclusion: In tongue cancer, downregulation of C-myc mRNA associated with advancement of the disease and worse prognosis.