Lack of association between methylenetetrahydrofolate reductase C677T polymorphism, HPV infection and cervical intraepithelial neoplasia in Brazilian women

Abstract

Background: Cervical cancer has high prevalence and mortality rates in worldwide female population. Persistent infection by high-risk Human Papillomavirus (hr-HPV) is the main cause of this cancer. However, many environmental, genetical, and epigenetical cofactors can modulate viral infection and cervical carcinogenesis. Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism is a genetic factor that has been associated with many pathologies, including cancer. Nevertheless, studies with cervical cancer presented controversial results, and varied according to ethnicity. Thus, the aim of this study was to determine association between MTHFR C677T polymorphism, Human Papillomavirus (HPV) infection and cervical cancer. Methods: A case-control study was performed with 150 histological cervical samples. Case group were divided in Cervical Intraepithelial Neoplasia (CIN) grade I (n = 30), CIN II (n = 30), CIN III (n = 30), and Squamous Cervical Carcinoma (SCC) (n = 30). Control group was composed by 30 samples without lesion, presenting cervicitis. HPV detection was performed by conventional Polymerase Chain Reaction (PCR) with SPF primers set, and by real-time PCR specific for HPV 16 and hr-HPV. MTHFR C677T polymorphism was analyzed by PCR followed by Restriction Fragment Length Polymorphism (RFLP). Results: Frequency of MTHFR CC genotype was 72.7% (n = 109), CT 23.3% (n = 35) and TT 4.0% (n = 6). Polymorphic T allele frequency was 15.7%. No statistically significant association was observed between MTHFR C677T polymorphism and presence of pre-neoplastic or neoplastic cervical lesions. Similar frequencies of T allele was observed in control (23.3%) and cases (13.3%) groups (p = 0.174). In addition, there was no statistically significant association between MTHFR C677T polymorphism and viral infection, even considering hr-HPV or HPV 16 positivity. Conclusion: MTHFR C677T polymorphism was not associated with cervical cancer and HPV infection.

Bacterial vaginosis: prevalence, risk profile and association with sexually transmitted infections

“…2 , 12 Samples from forty women with BV detected by the Gram staining and forty women without BV were randomly selected and submitted for Trichomonas vaginalis (T. vaginalis), Neisseria gonorrhoeae (N. gonorrhoeae), Chlamydia trachomatis (C. trachomatis) and Human Papilloma Virus (HPV) detection by Polymerase Chain Reaction (PCR). 3,17,18 Databases were generated using EpiData version 3.2 (EpiDataAssociation, Odense, Denmark) by double entry of the results, and they were subsequently compared, corrected, and analyzed using STATA version 14.0 software (Stata Corp., College Station, TX, USA).…”

Cervical Neoplasia: Papillomavirus Infection and Resistance to Anti Tumor Immunity

“…This study shows that out of a total of 107 women with a lesion of the cervix, 50 of them have intraepithelial neoplasms of the cervix, a frequency of 46.7%. In the study of intraepithelial neoplasia of the cervix in Brazilian women, the authors found 90 cases of intraepithelial neoplasias in 150 cervical samples, or 60% of cases [50]. Mwenze et al, in a study carried out in Lubumbashi on screening for cervical cancer in the population, observed a frequency of intraepithelial neoplasia of the cervix equal to 13% within the population of Lubumbashi [51].…”

“…Although intraepithelial neoplasia is the most common lesions of the cervix [60]. Their proportions are much greater when the studies concern patients with clinically identifiable lesions [50]. But in cases where studies are done to screen a population for cervical cancer, the frequencies of intraepithelial neoplasms are relatively low [21].…”

Prevalence of neoplasia in solitary and multiple esophago-gastrointestinal polyps: 5 years retrospective histopathological study

“…The distribution of polyps, namely colorectal polyps which were more common in the left side of the colon than the right side, follows and parallels the distribution of colorectal cancer (48). Further study is needed to examine genome-wide association studies to identify candidate genes (49) and polymorphism (50)(51)(52) in different populations.…”