Polymorphism in exon 4 of TP53 gene associated to HPV 16 and 18 in Mexican women with cervical cancer

Unveiling the etiological impact of GST-M1, GST-T1, and P53 genotypic variations on brain carcinogenesis

BACKGROUND

Functional variants of glutathione-S-transferase (GST)-M1, GST-T1, p53 might modulate brain cancer risk by altering the rate of metabolism and clearance of carcinogens from the brain tissue. In this study, the role of GST-M1, GST-T1, p53 polymorphisms on brain tumor was investigated.

METHODS AND RESULTS

Brain tumor tissues of 143 patients were obtained from the Gulhane Training and Research Hospital, Department of Neurosurgery between 2019 and 2020. In the xenobiotic mechanism, the null allele frequency in the GST-T1, GST-M1 gene regions of Phase II enzymes by qPCR method were investigated. Single nucleotide polymorphism encoding Arg/Pro conversion in the p53 gene region was analyzed in 120 cases by sequence analysis method. The data were analyzed statistically with patient's demographic and clinical data. GST-M1, GST-T1, p53 genotypes of the patient group were determined. The most frequent genotype was null genotype (0/0) for GST-M1 (χ2 = 39.756, p < 0.001). GST-M1 genotype frequencies were 30.8%, 23.1%, 44.3% for 1/1, 1/0, 0/0, respectively. The most frequent genotype was GST-T1 1/1 following by GST-T1 1/0 (χ2 = 0.335, p = 0.846). GST-T1 genotype frequencies were 64.3%, 30.8%, 4.9% for 1/1, 1/0, 0/0, respectively. GST-M1 null genotype might be associated with the development of brain tumors. Genotype distribution obtained in p53 exon 4 codon 72; Arg/Arg was determined as 31 (25.8%), Arg/Pro 70 (58.3%), and Pro/Pro 19 (15.8%) in the case group, while there were 18 (38.3%), 23 (48.9%), and 6 (12.8%) respectively in the control group. However, the genotype distribution of p53 exon 4 codon 72 among tumorous tissue did not significantly vary from healthy control tissues (χ²=2.536, p = 0.281).

CONCLUSION

The null allele frequency encountered in the GST-M1, GST-T1 gene regions is consistent with the rates in the gene pool called Caucasian in the literature. GST-M1 gene polymorphism may play a crucial role in brain carcinogenesis in Turkish patients. This study based on clinical data is thought to help to understand the important epidemiological features of brain tumors.

The precision prevention and therapy of HPV-related cervical cancer: new concepts and clinical implications

Cervical cancer is the third most common cancer in women worldwide, with concepts and knowledge about its prevention and treatment evolving rapidly. Human papillomavirus (HPV) has been identified as a major factor that leads to cervical cancer, although HPV infection alone cannot cause the disease. In fact, HPV-driven cancer is a small probability event because most infections are transient and could be cleared spontaneously by host immune system. With persistent HPV infection, decades are required for progression to cervical cancer. Therefore, this long time window provides golden opportunity for clinical intervention, and the fundament here is to elucidate the carcinogenic pattern and applicable targets during HPV-host interaction. In this review, we discuss the key factors that contribute to the persistence of HPV and cervical carcinogenesis, emerging new concepts and technologies for cancer interventions, and more urgently, how these concepts and technologies might lead to clinical precision medicine which could provide prediction, prevention, and early treatment for patients.

Polymorphism Located in the Upstream Region of the RPS19 Gene (rs2305809) Is Associated With Cervical Cancer: A Case-control Study

Cervical cancer (CC) is caused by persistent human papillomavirus (HPV) infection and affects women worldwide. The progression of an HPV persistent infection to CC is influenced by genetic factors. Three single nucleotide polymorphisms (SNPs) in TP53, NQO1 and RPS19 genes (rs1042522, rs1800566, rs2305809, respectively) were previously associated with CC in European and North American populations. The present case-control study aimed to investigate the association of the SNPs rs1042522, rs1800566, and rs2305809 with CC in an admixed population in southern Brazil. A total of 435 women (106 CC patients and 329 controls) were recruited for this study. All women were interviewed and underwent clinical sampling. SNPs rs1042522 and rs1800566 were evaluated by PCR-RFLP. SNP rs2305809 was determined by real-time PCR. The crude and adjusted ORs with 95% CI were estimated. The recessive genetic model (C/C + C/T) for rs2305809 was more frequent in the control group (79.9%) compared to the cases (69.8%), being associated with CC protection (_adjustedOR = 0.49; 95% CI: 0.27–0.90). However, the other polymorphisms evaluated did not present significant differences between cases and controls. This study detected a protective association for the recessive genetic model in rs2305809. These results suggest a potential role of the RPS19 gene in CC.

TP53 Arg72Pro polymorphism is associated with increased overall survival but not response to therapy in Portuguese/Caucasian patients with advanced cervical cancer

Identification of mechanisms that influence the therapeutic response and survival in patients with cancer is important. It is known that the genetic variability of the host, including presence of genetic polymorphisms in genes involved in DNA damage response, serves a crucial role in the prognosis of these patients. The present hospital-based retrospective cohort study aimed to evaluate the influence of TP53 Arg72Pro (rs1042522) polymorphism in the clinical outcome of 260 Caucasian patients diagnosed with cervical cancer and treated with concomitant radiotherapy and chemotherapy. The polymorphism genotyping was assessed using allelic discrimination by quantiative polymerase chain reaction. The results indicate that the TP53 Arg72Pro polymorphism did not significantly impact the response to therapy (P=0.571) nor disease-free survival (P=0.081). However, the polymorphism did influence overall survival, as increased median survival time was observed for patients carrying Arg/Pro genotype when compared with patients with Arg/Arg and Pro/Pro genotypes (126 months vs. 111 months, respectively; P=0.047). To conclude, the present findings suggest that a pharmacogenomic profile based on the genetic background of patients, including the analysis of the TP53 genotypes, may individualize treatment nad assist in the selection of therapies that may improve clinical outcome and lower toxicity for the patients.

Reduced rate of human papillomavirus infection and genetic overtransmission of TP53 72C polymorphic variant lower cervical cancer incidence

BACKGROUND

Cervical cancer is a predominantly human papillomavirus (HPV)‐driven disease worldwide. However, its incidence is unexplainably low in western Asia, including Saudi Arabia. Using this paradigm, we investigated the role of HPV infection rate and host genetic predisposition in TP53 G72C single nucleotide polymorphism (SNP) presumed to affect cancer incidence.

METHODS

Patients treated between 1990 and 2012 were reviewed, and a series of 232 invasive cervical cancer cases were studied and compared with 313 matched controls without cancer. SNP was genotyped by way of direct sequencing. HPV linear array analysis was used to detect and genotype HPV in tumor samples.

RESULTS

The incidence of cervical cancer revealed bimodal peaks at 42.5 years, with a slighter rebound at 60.8 years. Among all cases, 77% were HPV‐positive and 16 HPV genotypes were detected—mostly genotypes 16 (75%) and 18 (9%)—with no difference by age, histology, or geographical region. Although the TP53 G72C genotype was not associated with overall cervical cancer risk, it was significantly associated with HPV positivity (odds ratio, 0.57; 95% confidence interval, 0.36‐0.90; P = .016). Furthermore, the variant C allele was significantly overtransmitted in the population (P < .0003).

CONCLUSION

Cervical cancer incidence displays bimodal curve peaking at a young age with secondary rebound at older age. The combination of relative low HPV infection and variant TP53 72C allele overtransmission provide a plausible explanation for the low incidence of cervical cancer in our population. Therefore, HPV screening and host SNP genotyping may provide more relevant biomarkers to gauge the risk of developing cervical cancer. Cancer 2017;123:2459–66. © 2017 The Authors. Cancer published by Wiley Periodicals, Inc. on behalf of American Cancer Society. This is an open access article under the terms of the Creative Commons Attribution NonCommercial License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited and is not used for commercial purposes.

Cervical cancer incidence shows bimodal peaks at 43 years and relative rebound at 61 years of age. A reduced rate of human papillomavirus infection and overtransmission of the TP53 72C variant lower cancer incidence.

Human papillomavirus genotypes among females in Mexico: a study from the Mexican institute for social security

BACKGROUND

The aetiological relationship between human papillomavirus (HPV) infection and cervical cancer (CC) is widely accepted. Our goal was to determine the prevalence of HPV types in Mexican women attending at the Mexican Institute for Social Security from different areas of Mexico.

MATERIALS AND METHODS

DNAs from 2,956 cervical samples were subjected to HPV genotyping: 1,020 samples with normal cytology, 931 with low-grade squamous intraepithelial lesions (LGSIL), 481 with high grade HGSIL and 524 CC.

RESULTS

Overall HPV prevalence was 67.1%. A total of 40 HPV types were found; HPV16 was detected in 39.4% of the HPV-positive samples followed by HPV18 at 7.5%, HPV31 at 7.1%, HPV59 at 4.9%, and HPV58 at 3.2%. HPV16 presented the highest prevalence both in women with altered or normal cytology and HPV 18 presented a minor prevalence as reported worldwide. The prevalence ratio (PR) was calculated for the HPV types. The analysis of PR showed that HPV16 presents the highest association with CC, HPV 31, -33, -45, -52 and -58 also demonstrating a high association.

CONCLUSIONS

The most prevalent HPV types in cervical cancer samples were -16, -18, -31, but it is important to note that we obtained a minor prevalence of HPV18 as reported worldwide, and that HPV58 and -52 also were genotypes with an important prevalence in CC samples. Determination of HPV genotypes is very important in order to evaluate the impact of vaccine introduction and future cervical cancer prevention strategies.

[Study of codon 72 of p53 gene as a risk-factor in cervical cancer in Senegal]

Beside human papilloma virus infection, several genetic factors have been involved in susceptibility to cervical cancer. The arginine allele at codon 72 in p53 tumor suppressor gene has been reported to be a risk-factor in different ethnic groups. Our aim was to study this polymorphism as a risk-factor in Senegal. We conducted a case-control association study by recruiting 30 patients with cervical cancer clinically followed up in the Curie Institute in Dakar, and 93 healthy female controls without diagnosed cervical cancer. For each individual, DNA was extracted from whole blood. The codon 72 polymorphism was genotyped by PCR-RFLP. We did not find any association between the arginine allele and susceptibility to cervical cancer in our population (P = 0.354). Moreover, any correlation between the arginine allele and histological lesions was observed. Even if we did not find any correlation between the arginine allele and susceptibility to cervical cancer, p53 as a tumor suppressor gene remains a good genetic marker in tumours biology.

MTHFR/p53 Polymorphisms as Genetic Factors for Cervical Intraepithelial Neoplasia and Cervical Cancer in HPV-infected Mexican Women

We performed a case-control association study to evaluate the association between common polymorphisms in MTHFR (C677T and A1298C) and the Arg72Pro polymorphism in the p53 gene and the risk for cervical intraepithelial neoplasia (CIN) or invasive cervical cancer (ICC) in Mexican HPV-infected women. We included 131 women with diagnosis of CIN grade I-II and 78 with CIN III or ICC; as controls we also included 274 women with normal Pap smear and negative HPV test. Genotyping for MTHFR and p53 polymorphisms was performed by PCR-RFPLs. HPV was tested by Hybrid Capture II. Odds ratios and 95% confidence intervals were estimated. Genotype frequencies for the 3 studied polymorphisms were distributed according to the Hardy-Weinberg equilibrium. The A1298C-MTHFR polymorphism showed significant differences for the heterozygous AC genotype and the C allele, whereas the AA genotype and A allele resulted to be genetic risk factors for CIN or ICC (p<0.03). The Arg72Pro-p53 polymorphism showed for the genotypes Arg/Pro and Pro/Pro, and for the Pro allele, a significant association only to the risk for CIN (p<0.03). The MTHFR/p53 interaction showed that the genotype combinations AA/ArgArg and AA/ArgPro were associated, respectively, to the risk of ICC and CIN (p<0.05). This study suggests that the A1298C-MTHFR polymorphism contributes to the genetic risk for both CIN and ICC, whereas the Arg72Pro-p53 polymorphism only contributes to the risk for CIN. The MTHFR/p53 genetic combinations AA/ArgArg and AA/ArgPro are associated genetic risk factors for ICC and CIN in Mexican HPV-infected women.

Association of TP53 codon 72 and intron 3 16-bp Ins/Del polymorphisms with cervical cancer risk

Cervical cancer incidence has grown worldwide, with it being a more significant problem in developing countries. Invasive squamous cell cervical cancers are preceded by a long phase of preinvasive disease, known as cervical intraepithelial neoplasia. Cervical cancer can develop when the virus takes advantage of any TP53 gene dysfunction of the host organism. TP53 is responsible for encoding the tumor suppressor p53 phosphoprotein, which helps preserve genome integrity. Currently, many studies have focused on genetic polymorphisms as an important contribution to cancer susceptibility, but few related to cervical intraepithelial neoplasia (CIN). Thus, the present study aimed to see whether patients with suspected CIN had TP53 gene polymorphisms that might have contributed to the development of neoplasia. This study included 133 women who were referred to the Cervical Pathology Clinic of the Maternity School Assis Chateaubriand MEAC for suspected cervical lesions. Polymorphism genotyping was carried out by the PCR-RFLP technique using DNA extracted from patients' blood. The most frequent genotype in both CIN(+) and CIN(-) patients was Arg/Pro TP53 codon 72 and A1A1 for 16-bp Del in intron 3. No risk of cervical cancer was found for the polymorphisms studied. However, a significant association was found when the two polymorphisms were combined: patients with the A1A1/ArgPro genotype were statistically more frequent in the CIN(-) group (p = 0.042), while A2A2-A1A2/ProArg was significantly more frequent in the CIN(+) group. The results of our study suggest that combined analysis of TP53 polymorphisms Arg72Pro and 16-bp Ins/Del may help to monitor the development of CIN in Brazilian women.