Expression of Radioresistant Gene PEG10 in OSCC Patients and Its Prognostic Significance

Background: Oral squamous cell carcinoma (OSCC) is one of the most common forms of cancer occurring worldwide. PEG10 is well known as a paternally expressed gene from a newly recognized imprinted region at human chromosome 7q21. Previous study had demonstrated that the significant expression of PEG10 was found in radioresistant OSCC cell line and its expression was significantly associated with poor survival in several cancers. Therefore it has been evaluated as a potential marker in OSCC patients undergoing radiotherapy. Objective: This study was conducted to analyze the mRNA expression of PEG10 in OSCC and its expression in relation to clinicpathological features, radiotherapy treatment response and survival. Methods: This study included tissue specimens obtained via biopsy of 118 patients with OSCC who were recommended for radiotherapy treatment and 80 healthy control tissues analysis of mRNA expression of PEG10 was done by real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Patients were treated with 70 Gy of radiation dose by shrinking field technique using Cobalt-60 teletherapy machine. Results: Significantly higher mRNA expression of PEG10 was found in OSCC patients when compared with matched controls. High level of PEG10 mRNA expression showed a significant correlation with lymph node metastasis (p = 0.0047) and tumor stage (p = 0.0499). Multivariate Cox regression analysis revealed that high level of mRNA expression of PEG10 was significantly associated with poor survival (p < 0.05). Our research demonstrated that the expression of PEG10 was higher in radioresistant tumor. Conclusion: We observed significantly increased expression of PEG10 in context of lymph node status, advanced stage and poor survival in our study. Thus PEG10 gene can be used as potential predictive and prognostic biomarker in OSCC patients undergoing radiotherapy.