Genetic polymorphisms Tp53, CYP1A1 and GSTM1, in oral cancer and oral potentially malignant disorders, in patients from Córdoba, Argentina.

UNAMUNO, V.; CARRICA, A.; IRAZUZTA, G.; GALINDEZ COSTA, M. F.; BARRA, J. L.; ZARATE, A. M.; PANICO, R.

Roma

Congreso; 7th WORLD CONGRESS of the International Academy of Oral Oncology; 2019

IAOO

Objective: To measure polymorphisms of the Tp53, CYP1A1 and GSTM1 genes in patients with oral cancer (OC) and oral potentially malignant disorders (OPMD).Material and methods: 140 patients were studied: 41 with OC, 61 with OPMD (lichens or leukoplakias) and 38 controls (Con).Biopsies and exfoliative cytology (EC) of lesion and healthy contralateral were taken. DNA was extracted from healthy EC cells by performing polymorphisms of Tp53Arg72Pro and GSTM1 (absent or present polymorphism) by conventional PCR and CYP1A1 (mutation found in the 3-flanking region) by PCR and RFLP analysis using MspI restriction enzyme.Results: For Tp53 the genotypes CC, CG, GG were obtained; in Con 86% presented GC o CC (p=0,0344) , in OPMD 69% had GC genotype(p=0,0001) and in OC el 80% presented GC or GG (p= 0,0002).For CYP1A1 genotypes obtained were: m1 / m1 (wild type), m1 / m2 and m2 / m2. All control patients presented m1 / m1 and 72% of OC patients presented genotype m1 / m1 (p = 0.0001); in OPMD, the majority of patients (83%) presented genotypes m1 / m1 and m2 / m2 (p = 0.0183). For GSTM1, the genotypes (not null) wild type and (null) were observed; with a non-null genotype in 72% of Con (p = 0.007); in OC, 63% of patients presented null genotype (p= 0,0956) and in OPMD 62% (0,6858) had this genotype but there were not significant differences in between the groups.In the logistic regression it was observed: a) a significant association between the presence of the proline variant of the TP53 gene codon 72 and the presence of DOPM (p = 0.0043) and OC (p = 0.0295), observing that 4.57 times more chance of present the proline variant if the patient has DOPM and 3.24 times more chance of presenting this variant if the patient presents OC; b) significant association between the presence of the null variant of the GSTM1 gene and the presence of DOPM (p = 0.0206) and OC (p = 0.0027), observing 2.90 times more chance of presenting the null variant if the patient has OPMD and 4.60 times more chance of presenting this variant if the patient presents OC. Conclusions: the presence of the Tp53 CC genotype and GSTM1 null could show a higher predisposition to premalignant lesions and oral cancer.