Methylation of TGM-3 Promoter and Its Association with Oral Squamous Cell Carcinoma (OSCC)

Sorour Shojaeian; Abdolkarim Moazeni-Roodi; Abdolamir Allameh; Ata Garajei; Anoshirvan Kazemnejad; Kourosh Kabir; Amir-Hassan Zarnani

doi:10.18502/ajmb.v13i2.5523

Methylation of TGM-3 Promoter and Its Association with Oral Squamous Cell Carcinoma (OSCC)

Avicenna J Med Biotechnol. 2021 Apr-Jun;13(2):65-73. doi: 10.18502/ajmb.v13i2.5523.

Authors

Sorour Shojaeian¹, Abdolkarim Moazeni-Roodi², Abdolamir Allameh³, Ata Garajei^{4

5}, Anoshirvan Kazemnejad⁶, Kourosh Kabir⁷, Amir-Hassan Zarnani^{8

9}

Affiliations

¹ Department of Biochemistry, Alborz University of Medical Sciences, Karaj, Iran.
² Department of Clinical Biochemistry, Iranshahr University of Medical Sciences, Iranshahr, Iran.
³ Department of Clinical Biochemistry, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
⁴ Department of Oral and Maxillofacial Surgery, Faculty of Dentistry, Tehran University of Medical Sciences, Tehran, Iran.
⁵ Department of Head and Neck Surgical Oncology and Reconstructive Surgery, The Cancer Institute, Faculty of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
⁶ Department of Bio-statistics, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
⁷ Department of Community Medicine, Alborz University of Medical Sciences, Karaj, Iran.
⁸ Department of Immunology, Faculty of Public Health, Tehran University of Medical Sciences, Tehran, Iran.
⁹ Reproductive Immunology Research Center, Avicenna Research Institute, ACECR, Tehran, Iran.

Abstract

Background: Oral Squamous Cell Carcinoma (OSCC) is among the ten most common cancers worldwide. Hypermethylation of CpG sites in the promoter region and subsequent down-regulation of a tumor suppressor gene, TGM-3 has been proposed to be linked to different types of human cancers including OSCC. In this study, methylation status of CpG sites in the promoter region of TGM-3 has been evaluated in a cohort of patients with OSCC compared to normal controls.

Methods: Forty fresh tissue samples were obtained from newly diagnosed OSCC patients and normal individuals referred to dentistry clinic for tooth extraction. DNA was extracted, bisulfite conversion was performed and it was subjected to PCR using bisulfite-sequencing PCR (BSP) primers. Prepared samples were sequenced on a DNA analyzer with both forward and reverse primers of the region of interest. The peak height values of cytosine and thymine were calculated and methylation levels for each CpG site within the DNA sequence was quantified.

Results: Quantitative DNA methylation analyses in CpG islands revealed that it was significantly higher in OSCC patients compared to controls. DNA methylation at CpG1/CpG3/CpG5 (p=0.004-0.01) and CpG1/CpG3 (p=0.001-0.019) sites was associated with tumor stage and grade, respectively. Male OSCC patients had higher methylation rate at CpG3 (p=0.032), while smoker patients showed higher methylation rate at CpG6 (p=0.045).

Conclusion: These results manifested the contribution of DNA methylation of TGM-3 in OSCC and its potential association with clinico-pathologic parameters in OSCC.

Keywords: DNA methylation; Genetic; Oral squamous cell carcinoma; Promoter regions.