3-phosphoglycerate dehydrogenase gene polymorphism amongst patients with thyroid gland cancer

Abstract

Introduction: Thyroid gland cancer is a rare malignancy in the male population, accounting for up to 2% of all cancers, but it is the most common cancer of the endocrine system, making up to 95% of all estimated new endocrine cancer cases each year. Recent studies suggested an important role of both environmental and genetic factors in cancerogenesis. 3-Phosphoglycerate dehydrogenase (3-PHGDH) gene overexpression is associated with pathogenesis of human cancer and contributes to cell proliferation. Aim: To asses the association of PHGDH gene polymorphism in the group of patients with thyroid gland cancer and the control group of healthy men. Materials and methods: The study encompassed 80 men diagnosed with thyroid gland cancer in Center for Endocrine Surgery, Clinic for Endocrinology, Diabetes and Metabolic Diseases, Clinical Center of Serbia and 100 healthy male volunteers. The DNA was isolated from the peripheral blood with solting out method. The genotypes of 3-PHGDH polymorphism were determined by Polimerase Chain Reaction (PCR) and Restriction Fragment Lenght Polymorphism (RFLP). Gel-electrophoresis was used to separate DNA fragments. Results: There was a statistically highly significant difference between frequencies for genotype distribution of rs541503 polymorphism in patients with thyroid gland cancer and healthy volunteers (χ2 = 38.924; p=0.001). We found that in patients with thyroid gland cancer, the most common genotype is TT and in the control group TC. Major Allele Frequency (MAF (C)) in the control group in our study was 0.61. In patients with carcinoma of the thyroid gland MAF (C) was almost twice lower at 0.31. Allele frequencies in a group of patients with thyroid gland carcinoma compared to the control group showed a statistically significant difference (χ2 = 18.1159; p = 0.001). Conclusion: C allele could be a protective factor in the prevention of the thyroid gland cancer. People with TT genotype are six times more likely to develop thyroid cancer compared to those with the CC genotype.