Role of a p53 polymorphism in the development of human papillomavirus-associated cancer

Effect of TP53 rs1042522 on the susceptibility of patients to oral squamous cell carcinoma and oral leukoplakia: a meta-analysis

Background

There are different and inconsistent conclusions regarding the genetic relationship between the human tumor suppressor p53 (TP53) rs1042522 polymorphism and the risk of oral squamous cell carcinoma (OSCC) and oral leukoplakia (OL). Therefore, the aim of the study was to comprehensively reassess this association through the performance of an updated meta-analysis.

Methods

After searching the available databases, we systematically screened and included the eligible case-control studies, which contain the full genotype frequency data of the TP53 rs1042522 polymorphism for both OSCC/OL patients and the negative control groups. P_A (P-value of the association test) and ORs (odd ratios) with their corresponding 95% CIs (confidence intervals) were calculated to quantitatively evaluate the influence of TP53 rs1042522 on the susceptibility of patients to OSCC or OL.

Results

In total, twenty eligible case-control articles were finally enrolled. Compared with the controls, no increased or decreased risk of OSCC was observed in the cases for six genetic models including allele C vs. G (P_A = 0.741), carrier C vs. G (P_A = 0.853), homozygote CC vs. GG (P_A = 0.085), heterozygote GC vs. GG (P_A = 0.882), dominant GC + CC vs. GG (P_A = 0.969), and recessive CC vs. GG + GC (P_A = 0.980). Furthermore, no statistically significant difference between the cases and controls was detected in most subgroup meta-analyses (P_A > 0.05). For the risk of OL, we did not observe the difference between the cases and controls for most genetic models in the overall meta-analysis and subsequent subgroup analysis (P_A > 0.05). Begg’s test and Egger’s test excluded the large risk of publication bias within the included studies in the meta-analysis of OSCC. The sensitivity analysis indicated the above relatively stable results.

Conclusions

Our updated meta-analysis (based on the current evidence) shows that TP53 rs1042522 may not confer susceptibility to OSCC. In addition, for the first time, we provided evidence regarding the negative association between TP53 rs1042522 and OL risk.

Electronic supplementary material

The online version of this article (10.1186/s12903-018-0603-6) contains supplementary material, which is available to authorized users.

Exploring the Causes of the Low Incidence of Cervical Cancer in Western Asia

Anecdotal epidemiologic observations can provide valuable tools to study various biologic elements in complex diseases such as cancer. Although cervical cancer is one of the most frequent malignancy affecting women in the world, it displays wide geographical variations remnant of socioeconomic, ethnic and genetic predisposing factors. The observed low incidence of cervical cancer in western Asia has triggered scientists to try to delineate the causes of this reduced occurrence. Although this region including Saudi Arabia is known for being conservative societies with low incidence of sexually transmitted infections including human papillomavirus (HPV) and associated cervical cancer, scientific research points out multifaceted biological explanations including host genetic variations. Researchers observed that a protective genetic variant TP53 codon 72 proline allele was more commonly found in this population and appear to be over-transmitted compared to others known for their high rate of cervical cancer. Thus, the combination of relative low rate of HPV infection, over-transmission of protective genetic variant along with societal variables are the rationale behind the low incidence of cervical cancer in women in the region of western Asia. The influence of the genetic makeup of the patients has impact on personalized preventive medicine to gauge the risk of developing cervical cancer.

TP53 rs1625895 is Related to Breast Cancer Incidence and Early Death in Iranian Population

Breast cancer as the second most common cancer worldwide tend to be experienced by Iranian women 10 years earlier with a peak incidence at the premenopausal stage. Genetic mutations of TP53 tumor suppressor gene has been shown to be related to early onset of breast cancer. It has been shown already that rs1625895 polymorphic site is related to glioma as well as lung cancer. In this study, we have investigated the role of rs1625895 polymorphism in breast cancer incidence in Iranian women. DNA extraction of 86 breast cancer patients and 96 control individuals have been used for allele-specific primer-PCR and genotyping of allele A and allele G of the TP53 rs1625895. Genotypes frequencies have been shown that GG homozygosis as the most frequent genotype is a significant association with increased risk of breast cancer development in Iranian women (odds ratio = 6, p = 0.002). On the other hand and in comparison to allele G, allele A could cause early death of breast cancer patients by threefolds significantly (p = 0.011). As a conclusion, we show that allele A is the minor allele in both breast cancer patients and also control individuals and major allele G, is related to the increased risk of breast cancer development in Iranian women.

Impact of p53 arg72pro SNP on Breast Cancer Risk in North Indian Population

Background:

Genetic changes in p53 gene contribute to breast cancer susceptibility.

Objective and Methods:

A case-control study and a meta-analysis were performed to investigate the role of p53 codon72 SNP with breast cancer susceptibility in Indian women.

Results:

p53 heterozygous arginine variant was associated with decreased risk of breast cancer in total cohort. In meta-analysis, Allelic and GG vs. CC genetic comparison model were found to be associated with breast cancer risk. Moreover, recessive comparison model indicated a protective correlation with breast cancer occurrence.

Conclusion:

The findings of our case-control study and meta-analysis suggest a significant association between p53 Arg72Pro polymorphism and an increased risk of breast cancer in Indian population.

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.

TP53 codon 72 polymorphism may predict early tumour progression in paediatric pilocytic astrocytoma

Pilocytic astrocytoma and ganglioglioma may occur in inaccessible or surgically difficult areas. In case of incomplete resection, the availability of biological predictors of tumour progression could be particularly important. To this end, an analysis of p53 codon 72 polymorphism and assessment of its role as prognostic marker were performed.

The status of the p53 Arg72Pro polymorphism was evaluated by pyrosequencing method in a multicenter cohort of 170 paediatric patients. Genotype/phenotype associations were investigated either by means of bivariate or multivariate analyses.

In the partially resected pilocytic astrocytomas, the Arg/Arg variant predicts early tumour progression (median survival time: 23.1 months) and is associated with poor event-free survival (p value = 0.0009). This finding remains true also in case of adjuvant therapies, with a 5-year event-free survival of 30.6% for cases with Arg/Arg variant vs. 78.7% for those with other genotypes. There is no association between ganglioglioma and the polymorphism.

The assessment of Arg/Arg variant could improve the management of pilocytic astrocytoma. TP53 codon 72 analysis could distinguish low-risk cases, in which surgery could be conservative, from high-risk cases needing an aggressive surgery plan.

Slug inhibits the proliferation and tumor formation of human cervical cancer cells by up-regulating the p21/p27 proteins and down-regulating the activity of the Wnt/β-catenin signaling pathway via the trans-suppression Akt1/p-Akt1 expression

Slug (Snai2) has been demonstrated to act as an oncogene or tumor suppressor in different human cancers, but the function of Slug in cervical cancer remains poorly understood. In this study, we demonstrated that Slug could suppress the proliferation of cervical cancer cells in vitro and tumor formation in vivo. Further experiments found that Slug could trans-suppress the expression of Akt1/p-Akt1 by binding to E-box motifs in the promoter of the Akt1 gene and then inhibit the cell proliferation and tumor formation of cervical cancer cells by up-regulating p21/p27 and/or down-regulating the activity of the Wnt/β-catenin signaling pathway. Therefore, Slug acts as a tumor suppressor during cervical carcinogenesis.

TP53 R72P Polymorphism and Susceptibility to Human Papillomavirus Infection Among Women With Human Immunodeficiency Virus in Morocco: A Case-control Study

Background

Human papillomavirus (HPV) is the most common sexually transmitted agent worldwide. HPV is the main causative agent for cervical cancer. The HPV oncoprotein E6 binds to the tumor suppressor gene product p53, promoting its degradation; the Arg allele of TP53 R72P polymorphism binds more ardently with HPV E6 than the Pro variant. Here, we investigated whether TP53 R72P gene variant, rs104252, was associated with susceptibility to HPV infection in women with human immunodeficiency virus (HIV).

Methods

We analyzed 200 HPV-positive and 68 uninfected women with HIV. Genomic DNA was isolated from cervical swab. The TP53 R72P polymorphism was genotyped by PCR-RFLP. Unconditional logistic regression was used to assess the association between polymorphism and the clinical, lifestyle, and behavioral data.

Results

The genotype and allele frequencies of rs104252 variant did not differ between women without or with HPV infection (P > 0.05). Moreover, the p53 polymorphism was not associated with cervical cytology. In contrast, when we analyzed according to behavior factors, the P72P genotype was more frequent among HPV-positive smoker women. However, no significant relationship was found between alcohol, contraceptive use, and number of partners with TP53 R72P genotype distributions among HPV-positive cases (P > 0.05).

Conclusions

The R72 variant of p53 R72P is not associated with HPV infection and progression of lesions. There was no association between this variant and behavior factors in HPV-positive cases. The P72P genotype may be more frequent among HPV-positive smoker women.

Association of p53 codon 72 Arg>Pro polymorphism and risk of cancer in Iranian population: A systematic review and meta-analysis

Background: Different studies have investigated the association between p53 codon 72 Arg>Pro polymorphism and cancer risk. Because of the lack of consensus of the results in individual studies, we conducted this meta-analysis by pooling all currently available case-control studies to estimate the effect of p53 codon 72 Arg/Pro polymorphism on cancer susceptibility in Iranian population. Methods: A comprehensive search was undertaken and primary data from all peer-reviewed journals indexed in PubMed, Google Scholar, Scopus, Magiran, Scientific Information Databank (SID), Iran Medex, and CAB abstract electronic were used to conduct this meta-analysis. We considered some exclusion and inclusion criteria to select the articles. Statistical heterogeneity was explored using the I-square. Publication bias was assessed graphically and statistically by Begg's funnel plot and Egger test. All statistical analyses were performed using StatsDirect software and a two- tailed test. P-value less than 0.05 was considered statistically significant for any test. Results: Our dataset, which included 35 case-control studies, consisted of 2426 cancer cases and 2928 controls. Pooled OR and 95%CI indicated that codon 72 Arg>Pro polymorphism was not associated with odds of developing cancer among Iranian population in the dominant model (Pro/Pro+Arg/Pro vs. Arg/Arg: OR= 0.96, 95%CI= 0.74 to 1.24 chi2= 0.06, p= 0.8). Moreover, no significant association was detected in variant allele (Pro vs Arg: OR= 1.075, 95%CI= 0.91 to 1.25), homozygous (Pro/Pro vs Arg/Arg: OR=0.911 95%CI= 0.66 to 1.25), and heterozygous (Arg/Pro vs Arg/Arg: OR= 0.84, 95%CI= 0.7 to 1). Conclusion: Our study revealed that p53 codon 72 Arg>Pro polymorphism was not associated with overall cancer odds in Iranian population.

No association between TP53 Arg72Pro polymorphism and ovarian cancer risk: evidence from 10113 subjects

The TP53 gene product is an important regulator of cell growth and a tumor suppressor. The association between TP53 Arg72Pro polymorphism and ovarian cancer risk has been widely investigated, but the results are contradictory. We therefore searched the PubMed, EMBASE and Chinese Biomedical databases for studies on the relation between TP53 Arg72Pro polymorphism and ovarian cancer risk. Our final meta-analysis included 24 published studies with 3271 cases and 6842 controls. Pooled results indicated that there was no significant association between TP53 Arg72Pro polymorphism and ovarian cancer risk [Pro/Pro vs. Arg/Arg: odds ratio (OR) =1.04, 95% confidence interval (CI) = 0.81-1.34; Arg/Pro vs. Arg/Arg: OR = 1.14, 95% CI = 0.96-1.36; recessive: OR = 1.05, 95% CI = 0.90-1.22; dominant: OR = 1.12, 95% CI = 0.94-1.33; and Pro vs. Arg: OR = 1.06, 95% CI=0.93-1.20]. Likewise, stratified analyses failed to reveal a genetic association. Despite some limitations, the present meta-analysis provides statistical evidence indicating a lack of association between TP53 Arg72Pro polymorphism and ovarian cancer risk.

Genetic Predisposition to Cervical Cancer and the Association With XRCC1 and TGFB1 Polymorphisms

Objective

Cervical carcinoma (CC), a multifactorial cancer, is assumed to have a host genetic predisposition component that modulates its susceptibility in various populations. We investigated the association between CC risk in Saudi women and 6 single-nucleotide polymorphisms (SNPs) in hypothesis-driven candidate genes.

Methods

A total of 545 females were included, comprising 232 CC patients and 313 age-/sex-matched control subjects. Six SNPs (CDKN1A C31A, ATM G1853A, HDM2 T309G, TGFB1 T10C, XRCC1 G399A, and XRCC3 C241T) were genotyped by direct sequencing.

Results

Of the 6 SNPs studied, TGFB1 T10C (odds ratio, 0.74; 95% confidence interval, 0.57–0.94) and XRCC1 G399A (odds ratio, 1.45; 95% confidence interval, 1.11–1.90) displayed different frequencies in cancer patients and control subjects and showed statistically significant association in univariate (P = 0.017, P = 0.005, respectively) analysis. The Cochran-Armitage trend test had confirmed the results (P = 0.027 and P = 0.006, respectively), indicating an ordering in the effect of the risk alleles in CC patients. The 2 SNPs, TGFB1 T10C and XRCC1 G399A, showed also degrees of deviation from Hardy-Weinberg equilibrium in cancer patients (P = 0.001 and P = 0.083, respectively) but not in the control subjects. Furthermore, correction for multiple testing using multivariate logistic regression to assess the joint effect of all SNPs has sustained significant statistical association (P = 0.025 and P = 0.009, respectively).

Conclusions

TGFB1 T10C and XRCC1 G399A SNPs were associated with CC risk in univariate and multivariate analysis and displayed allele-dosage effects and coselection in cancer patients. Patients harboring the majority allele TGFB1 T10 (Leu) or the variant allele XRCC1 399A (Gln) have approximately 1.5-fold increased risk to develop CC. Host SNPs genotyping may provide relevant biomarkers for CC risk assessment in personalized preventive medicine.

Association of p53 Codon 72 Polymorphism with Breast Cancer in a Rwandese Population

BACKGROUND AND AIMS

A common polymorphism in the tumor suppressor gene p53 at codon 72 has been suggested to play a role in the development of a number of cancers. This polymorphism has been studied in many populations worldwide, with conflicting results. The present study was planned to assess the association of p53 codon 72 polymorphism with breast cancer development in a Rwandese population.

METHODS

In this study, the polymorphism was examined by allele-specific PCR analysis in 40 patients with breast cancer and 39 healthy controls.

RESULTS

The heterozygous genotype Pro/Arg prevailed in both breast cancer patients and controls, and was present in 80% (32/40) and 92.3% (36/39) of cases, respectively. No statistically significant association was observed between p53 codon 72 polymorphism and breast cancer risk. Distribution of p53 genotypes was also studied according to familial history, tumor grade, and clinical stage, and results clearly showed no statistically significant difference.

CONCLUSION

These results suggest that p53 codon 72 polymorphism could not be assessed as a risk factor marker for predisposition to breast cancer in Rwanda. However, further studies using larger sample sizes are needed to provide more conclusive results and to investigate other genetic mutations affecting the activity of p53.

Association of codon 72 polymorphism of p53 with the severity of cervical dysplasia, E6-T350G and HPV16 variant lineages in HPV16-infected women

Purpose. Polymorphic variability in the tumour-suppressor protein p53 at codon 72 has a considerable impact on cervical cancer development. The present study clarified the association between p53 codon 72 genotypes and the risk of cervical disease in Greek patients. We also examined whether the presence of specific p53 genotypes in combination with HPV16 variants or E6 T350G sequence variation can modify an individual's susceptibility to cervical disease.Methodology. The analysis of p53 genotypes was performed through PCR-RFLP. Sequence and phylogenetic tree analyses of the HPV16 E6 gene were also performed in order to identify HPV16 variants and T350G sequence variation.Results/Key findings. The outcomes of the present analysis revealed that women who are homozygous for the arg genotype are at a 4.17-fold higher risk of developing HPV16-associated HSIL+ (OR=4.17, 95 % CI:1.48-4.9, P=0.0049). Moreover, p53 arg/arg patients infected by an HPV16 prototype strain were associated with an increased risk of more severe lesions, while a significant relationship between the p53 arg/arg genotype in patients with T350G sequence variation and the risk of high-grade squamous intraepithelial lesions (HSILs) was revealed.Conclusion. The oncogenic potential of the virus is increased by the presence of the p53 arg/arg genotype in the Greek population in such a way that the specific protein interaction E6 (L83V)-p53 (Arg-72) can modify an individual's susceptibility to cervical disease.

Human Genetic Determinants of Viral Diseases

Much progress has been made in the identification of specific human gene variants that contribute to enhanced susceptibility or resistance to viral diseases. Herein we review multiple discoveries made with genome-wide or candidate gene approaches that have revealed significant insights into virus-host interactions. Genetic factors that have been identified include genes encoding virus receptors, receptor-modifying enzymes, and a wide variety of innate and adaptive immunity-related proteins. We discuss a range of pathogenic viruses, including influenza virus, respiratory syncytial virus, human immunodeficiency virus, human T cell leukemia virus, human papilloma virus, hepatitis B and C viruses, herpes simplex virus, norovirus, rotavirus, parvovirus, and Epstein-Barr virus. Understanding the genetic underpinnings that affect infectious disease outcomes should allow tailored treatment and prevention approaches in the future.

Association of Cervical Cancer Screening with Knowledge of Risk Factors, Access to Health Related Information, Health Profiles, and Health Competence Beliefs among Community-Dwelling Women in Japan

Objective: The aim of this study was to evaluate the past attendance for cervical cancer screening with knowledge of risk factors, access to health-related information, health profiles and health competence beliefs among Japanese women. Methods: Women ages 25, 30, 35, 40, 45, 50, 55, and 60 were contacted cross-sectionally as part of a project for the Japanese Ministry of Health, Labour and Welfare in Nikaho, Akita prefecture Japan between June 2010 and March 2011, and 249 women were analyzed for the current study. The questionnaire asked about past cervical cancer screening. Knowledge of each cervical cancer risk factor was determined on a four-point scale. A barriers to information access scale was utilized to assess the degree of difficulty in accessing health-related information. Health profiles were measured using the EuroQOL EQ-5D. Perceived health competence was measured using a scale (PHCS). The association was evaluated with odds ratios with 95% confidence interval were calculated from a logistic regression analysis after adjustment for age and potential confounders. The trend across the level was also assessed. Results: Women who knew that sexual intercourse at young age was a risk factor were significantly more likely to have participated in cervical cancer screening sometime in their lives (p for trend =0.02). Women who had pain/discomfort and those who had anxiety/depression were significantly more likely to have participated in cervical screening within the past two years (odds ratio [OR]: 2.02, 95% confidence interval [CI]: 1.04–3.94; OR: 2.32, 95% CI: 1.05–5.16, respectively). Women with higher PHCS were significantly more likely to have attended for cervical screened at some point in their lives (p=0.04). Conclusion: This study observed that specific knowledge of cervical cancer risk factors, health profiles and PHCS were associated with the past attendance for cervical cancer screening among women in a community. Further researches are warranted.

Lack of evidence of HPV etiology of prostate cancer following radical surgery and higher frequency of the Arg/Pro genotype in Turkish men with prostate cancer

Objectives

The aim of this study was to assess the possible role of HPV in the development of prostate cancer (PCa) and investigate the distribution of the p53 codon 72 polymorphism in PCa in a Turkish population.

Materials and methods

A total of 96 tissues, which had been obtained using a radical surgery method, formalin-fixed and parafin-embedded, were used in this study. The study group consisted of 60 PCa tissues (open radical prostatectomy) and the control group contained 36 benign prostatic hyperplasia tissues (BPH) (transvesical open prostatectomy). The presence of HPV and the p53 codon 72 polymorphism was investigated in both groups using real-time PCR and pyrosequencing.

Results

The results of the real-time PCR showed no HPV DNA in any of the 36 BPH tissue samples. HPV-DNA was positive in only 1 of the 60 PCa samples (1.7%). The HPV type of this sample was identified as HPV-57. The distribution of the three genotypes, Arg/Arg, Arg/Pro and Pro/Pro was found to be 45.6, 45.6, and 8.8% in the PCa group and 57.1%, 34.3% and 8.6% in the control group, respectively. Compared with the control group, patients with PCa had a higher frequency of the Arg/Pro genotype and Proline allele (odds ratio (OR)=1.67, 95% confidence interval (CI)=0.68-4.09, p=0.044; OR=1.13, 95% CI=0.76-1.68, p=0.021, respectively).

Conclusions

The results of the study do not support the hyphothesis that prostate cancer is associated with HPV infection but indicated that Proline allele can be a risk factor in the development of PCa in the Turkish population.

Effect of p53 codon 72 polymorphism on the survival outcome in advanced stage cervical cancer patients in India

Background & objectives:

The Arg>Pro polymorphism in codon 72 of p53 gene is known to affect the susceptibility of cervical cancer differently in different population worldwide although information regarding its role in determining survival status and disease outcome in patients is lacking. The present study was conducted to determine the genotype frequency and prognostic role of p53 codon 72 Arg>Pro polymorphism in patients with advanced stage cervical cancer in India.

Methods:

The p53 codon 72 polymorphism was determined in tumour biopsies (n = 107) and matched blood samples (n = 19) in cervical cancer patients using polymerase chain reaction-restriction fragment length polymorphism method (PCR-RFLP). Effect of p53 genotype on the overall survival (OS) and recurrence-free survival (RFS) was analyzed. Individual Arg or Pro alleles were studied for their significance on survival as Pro carriers (Pro/Pro + Arg/Pro) versus Arg/Arg individuals or Arg carriers (Arg/Arg + Arg/Pro) versus Pro/Pro individuals.

Results:

The frequencies for Arg/Arg, Arg/Pro and Pro/Pro genotypes were 27.2, 49.5 and 23.3 per cent, respectively. There was no significant difference in the genotypes with respect to patients’ OS or RFS.

Interpretation & conclusions:

The findings of our study indicated that p53 codon 72 polymorphism might not be an independent marker in predicting clinical outcome in advanced stage cervical cancer patients. Further studies need to be done in larger samples to confirm these findings.

Detection of HPV genotypes and their association with p53 codon 72 polymorphism in prostate cancer

Aim: In this study, we focused on the p53 codon 72 polymorphism and HPV infections as a possible contributing factor in susceptibility to prostate cancer (PCa). Methods: Eighty histopathologically confirmed prostate biopsies comprising of 40 cancer cases and 40 benign prostate hyperplasia cases were used. Results: A significant difference was not observed between HPV presence and PCa progression. Our results showed that the p53 protein with Arg (p53-Arg72) variant contributes to the development of PCa. Conclusion: There is a near-significant association between Arg/Arg polymorphism and PCa.

Role of a p53 polymorphism in the development of nonfunctional pituitary adenomas

Non-functional pituitary adenomas (NFPAs) are among the commonest intracranial neoplasms. While histologically benign, NFPAs sometimes become large enough to limit therapeutic options and reduce quality of life. Investigations of the molecular etiology of NFPAs have failed to identify prevalent genetic changes and, while a role for p53 has been suggested, TP53 gene alterations have yet to be described in NFPAs. We found that the polymorphism rs1042522:C > G in codon 72 of exon 4 of the TP53 gene, whose C variant produces a proline and is more common in most ethnicities, has a G variant producing an arginine in 79.8% of NFPAs (n = 42; p < 1.411 × 10^-18 vs. 1000 Genomes database), causing patients to present a decade earlier with symptomatic NFPAs. In cultured NFPA cells, transfection with the rs1042522 G variant versus the C variant reduced expression of cell arrest gene p21 and increased proliferation. These findings suggest that this TP53 polymorphism influences NFPA growth.

Placenta-Specific Protein 1 Expression in Human Papillomavirus 16/18-Positive Cervical Cancers Is Associated With Tumor Histology

OBJECTIVE

Expression of the trophoblast-specific gene placenta-specific protein 1 (PLAC1) has been detected in a wide variety of cancers. However, to date, PLAC1 expression has not been shown in cervical cancer. We have carried out a preliminary study that shows for the first time that PLAC1 is expressed in cervical cancers.

METHODS

A total of 16 primary cervical tumors were obtained from patients shown to be human papillomavirus (HPV) 16/18 positive. Total cellular RNA, genomic DNA, and total protein were purified from each tumor. These materials were then used to determine PLAC1 expression, TP53 mutation status, and p53 expression.

RESULTS

The PLAC1 expression was demonstrated in all 16 primary cervical tumors. The highest levels of expression were found in the more aggressive squamous and adenosquamous histologic types compared with adenocarcinomas. Moreover, the proportion of total PLAC1 message coming from the P1 promoter, also termed the distal or cancer promoter, was significantly greater in the more aggressive squamous and adenosquamous histologic types compared with adenocarcinomas. Finally, in spite of all 16 tumors being HPV-16/18 positive, 3 of 8 squamous cell cancers and 2 of 5 adenocarcinomas expressed wild-type p53 protein. Consistent with the recently shown suppression of the PLAC1P1 promoter by wild-type p53, these p53 positive tumors displayed among the lowest P1-specific PLAC1 expression levels.

CONCLUSIONS

The PLAC1 expression has been demonstrated for the first time in cervical cancers. This preliminary study has further revealed a complex relationship between PLAC1 expression, cervical cancer histologic type, p53, and HPV type that requires further investigation.

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.

Combined Genetic Biomarkers Confer Susceptibility to Risk of Urothelial Bladder Carcinoma in a Saudi Population

We evaluated the associations between seven single nucleotide polymorphisms and susceptibility to urothelial bladder carcinoma (UBC) in a Saudi population. Genomic DNA was taken from buccal cells of 52 patients with UBC and 104 controls for genotyping of GSTT1, GSTM1, rs4646903, rs1048943, TP53 rs1042522, rs1801133, and rs1801394 using PCR and TaqMan® assays. The rs1801133 and rs1801394 variants showed strong associations with UBC (OR = 2.3, P = 0.0002; OR = 2.6, P = 0.0001, resp.). Homozygosity of Pro72 conferred a significant double risk in cases compared with controls (30.8% versus 15.4%), but the homozygote Arg/Arg had no effect on risk. Genotypic combinations of GSTM1/GSTT1, rs4646903/rs1048943, and rs1801133/rs1801394 exhibited significant linkage with the disease (χ² = 10.3, P = 0.006; χ² = 13.9, P = 0.003; and χ² = 20.4, P = 0.0004, resp.). The GSTM1 and rs1042522Arg and rs1801394G variant alleles were more frequent in current smokers with UBC (52.4%, 52.5%, and 64.3%, resp.) than were the corresponding wild-types. Despite some variants having only a slight effect on UBC risk, the interaction effect of combined genetic biomarkers-or even the presence of one copy of a variant allele-is potentially much greater. Perhaps more studies regarding next-generation genetic sequencing and its utility can add to the risk of UBC.

Does p53 codon 72 polymorphism have a prognostic value in carcinoma of the vulva and vagina?

Human papilloma virus (HPV) is considered to be responsible for a large part of vaginal and vulvar carcinomas, and the p53 codon 72 polymorphism has been implicated in susceptibility to cancer induced by this virus, but with contradicting results. In this study, we have investigated the prognostic value of the codon 72 polymorphism by real-time PCR (qPCR) in two cohorts of vaginal (n = 66) and vulvar (n = 123) carcinomas. In vaginal carcinoma, arginine homozygous patients were significantly associated with a higher primary cure rate (p = 0.023) but also associated with a higher recurrence rate (p = 0.073), significant at distant locations (p = 0.009). No significant differences were found in overall survival rate (p = 0.499) or cancer-specific survival rate (p = 0.222). A higher frequency of arginine homozygosity was noted in HPV-positive tumors (p = 0.190) in comparison with HPV-negative tumors. In vulvar carcinoma, the genotype homozygous for arginine was significantly associated with a larger tumor size at diagnosis in the entire cohort (p = 0.015) and a lower cancer-specific survival rate (p = 0.024) compared with heterozygous (arginine/proline) in HPV-negative tumors. Our results indicate that the relation between HPV and the p53 codon 72 polymorphism is complex and the significance and mechanisms responsible for this relationship need to be further elucidated.

p53 Codon 72 Gene Polymorphism Studies and p53 Expression by Immunohistochemistry in Oral Lesions as Risk Factor for Malignancy

Background:

Wild-type p53 nuclear phosphoproteins are critical cell cycle regulatory tumor-suppressor gene. Genetic mutation of p53 gene is common in several head–neck cancers, usually associated with smoking and human papillomavirus (HPV) infection. In India, instead of HPV, tobacco/pan masala chewing is more commonly associated with oral cancer.

Aim:

The aim of this study was to investigate p53 codon 72 gene polymorphism and expression of p53 by immunohistochemistry (IHC) in oral lesions as a risk factor for its association with malignancy.

Materials and Methods:

A total of 41 cases of oral lesions comprising 6 cases of leukoplakia and 35 cases of oral squamous cell carcinoma (OSCC), between 30 and 60 years age and tobacco/pan masala chewers were taken. Molecular analysis of p53 codon 72 gene polymorphism was performed by polymerase chain reaction – restriction fragment length polymorphism for Arg/Arg, Arg/Pro, and Pro/Pro. Tissue expression of p53 was done by IHC.

Results:

Genotype frequencies of 35 carcinoma cases of p53 Arg/Arg, Arg/Pro, and Pro/Pro were 23%, 57%, and 20%, respectively, and six leukoplakia cases of p53 Arg/Arg and Arg/Pro genotype were 50% and 50%, respectively. By IHC for expression of p53 out of 35 cases of OSCC biopsies, 17 (48.57%) had weak staining, 14 cases (40%) showed evidence of p53 protein staining, and four cases (11.42%) showed negative staining. Among six cases of leukoplakia, 3 (50%) showed weak staining and 3 (50%) showed negative results.

Conclusion:

The findings of the study indicate that there is no significant association between p53 codon 72 gene polymorphism with OSCC and leukoplakia associated with tobacco/pan masala chewing.

Combined Genetic Biomarkers Confer Susceptibility to Risk of Urothelial Bladder Carcinoma in a Saudi Population

We evaluated the associations between seven single nucleotide polymorphisms and susceptibility to urothelial bladder carcinoma (UBC) in a Saudi population. Genomic DNA was taken from buccal cells of 52 patients with UBC and 104 controls for genotyping of GSTT1, GSTM1, rs4646903, rs1048943, TP53 rs1042522, rs1801133, and rs1801394 using PCR and TaqMan® assays. The rs1801133 and rs1801394 variants showed strong associations with UBC (OR = 2.3, P = 0.0002; OR = 2.6, P = 0.0001, resp.). Homozygosity of Pro72 conferred a significant double risk in cases compared with controls (30.8% versus 15.4%), but the homozygote Arg/Arg had no effect on risk. Genotypic combinations of GSTM1/GSTT1, rs4646903/rs1048943, and rs1801133/rs1801394 exhibited significant linkage with the disease (χ² = 10.3, P = 0.006; χ² = 13.9, P = 0.003; and χ² = 20.4, P = 0.0004, resp.). The GSTM1 and rs1042522Arg and rs1801394G variant alleles were more frequent in current smokers with UBC (52.4%, 52.5%, and 64.3%, resp.) than were the corresponding wild-types. Despite some variants having only a slight effect on UBC risk, the interaction effect of combined genetic biomarkers-or even the presence of one copy of a variant allele-is potentially much greater. Perhaps more studies regarding next-generation genetic sequencing and its utility can add to the risk of UBC.

Association between TP53 gene Arg72Pro polymorphism and Wilms' tumor risk in a Chinese population

Wilms' tumor is one of the most prevalent pediatric malignancies, ranking fourth in childhood cancer worldwide. TP53 is a critical tumor suppressor gene, which encodes a 53 kDa protein, p53. The p53 functions to protect against cancer by regulating cell cycle and apoptosis and maintaining DNA integrity. TP53 gene is highly polymorphic. Several TP53 gene polymorphisms have been considered to be associated with cancer risk. Of them, a nonsynonymous polymorphism, Arg72Pro (rs1042522 C>G), has been most extensively studied for the association with cancer risk; however, few studies have investigated its effect on Wilms' tumor. Because of the central role of p53 in cell cycle control, the TP53 gene Arg72Pro polymorphism is also a good potential candidate predisposition locus for this pediatric cancer. We genotyped this polymorphism in 145 patients and 531 cancer-free controls recruited from Chinese children by Taqman methodology. Overall, our result suggested a lack of association between the TP53 gene Arg72Pro polymorphism and Wilms' tumor. In the stratified analysis, we found that carriers of CG/GG genotypes had a significantly increased Wilms' tumor risk in children not older than 18 months (adjusted odds ratio =2.04, 95% confidence interval =1.003-4.13, P=0.049) compared with CC genotype carriers. Our study indicated that the TP53 gene Arg72Pro polymorphism may have a weak, age-related effect on Wilms' tumor risk in Chinese children. These findings need further validations in other populations with larger sample size.

Expression of Human Papillomavirus DNA and p53 Polymorphisms through Polymerase Chain Reaction in Normal Mucosa and Oral Leukoplakia Individuals with Deleterious Oral Habits

Context:

Oral leukoplakia (OL) is a well-recognized precancerous lesion with various etiological factors. Most commonly deleterious oral habits such as tobacco smoking and viral etiologies mainly human papillomavirus (HPV) play an important role. p53 polymorphisms mostly homozygous Arginine (Arg) allele has a greater risk of degradation by HPV. Hence, HPV infection and p53 polymorphisms may act as synergistic factors for increased the risk of malignant transformation in oral precancerous lesions.

Aims:

The aim of this study is to evaluate the risk of OL and its malignant transformation due to infection by HPV and p53 polymorphisms in the oral biopsy samples through polymerase chain reaction (PCR).

Subjects and Methods:

A total of 40 individuals were involved– 10 individuals were controls without deleterious habits, 15 were controls with deleterious habits, and 15 were with histologically confirmed OL individuals with deleterious habits. PCR and restriction fragment length polymorphism using sma1 enzyme were carried out to evaluate the expression of HPV and p53 polymorphisms.

Statistical Analysis Used:

Chi-square test, Fischer's exact t-test, and odds ratio.

Results:

(1) HPV DNA expression was higher in Leukoplakia individuals than controls. (2) p53 genotype with homozygous Arg was more in HPV-infected individuals.

Conclusions:

To conclude HPV infected OL cases were mostly with Arg/Arg type of p53 polymorphism.

Somatic Variations in Cervical Cancers in Indian Patients

There are very few reports that describe the mutational landscape of cervical cancer, one of the leading cancers in Indian women. The aim of the present study was to investigate the somatic mutations that occur in cervical cancer. Whole exome sequencing of 10 treatment naïve tumour biopsies with matched blood samples, from a cohort of Indian patients with locally advanced disease, was performed. The data revealed missense mutations across 1282 genes, out of 1831 genes harbouring somatic mutations. These missense mutations (nonsynonymous + stop-gained) when compared with pre-existing mutations in the COSMIC database showed that 272 mutations in 250 genes were already reported although from cancers other than cervical cancer. More than 1000 novel somatic variations were obtained in matched tumour samples. Pathways / genes that are frequently mutated in various other cancers were found to be mutated in cervical cancers. A significant enrichment of somatic mutations in the MAPK pathway was observed, some of which could be potentially targetable. This is the first report of whole exome sequencing of well annotated cervical cancer samples from Indian women and helps identify trends in mutation profiles that are found in an Indian cohort of cervical cancer.

Polymorphism at Codon 72 of the p53 Gene Is Not associated With Endometriosis in a Japanese Population

OBJECTIVE

Endometriosis is inherited as a complex trait, which means that multiple susceptibility genes interact with each other and the environment to produce the phenotype. Previous studies have implicated p53, a tumor suppressor gene, as a factor in the development of the disease. In a Japanese population, we investigated the frequency of the p53 polymorphism in women affected with endometriosis.

METHODS

We compared the distribution of the p53 codon 72 polymorphism in endometriosis cases (n = 111) and population controls consisting of female neonates (n = 180) by using polymerase chain reaction restriction fragment-length polymorphism analysis in a Japanese population.

RESULTS

The frequencies of the three p53 genotypes, Arginine (Arg)/Arg, Arg/Proline (Pro), and Pro/Pro in controls were 39.4%, 41.7%, and 18.9 %, respectively. The crude genotype frequencies in the endometriosis cases were similar to those of the controls (35.2%, 48.6%, and 16.2%, respectively). Using the Arg/Arg genotype as the reference, the odds ratios of the Arg/Pro and Pro/Pro genotypes were 1.30 (95% confidence interval [CI] 0.72-1.86, P =.33) and 0.96 (95% CI 0.47-1.94, P =.91), respectively. Thus, there were no significant differences in the frequency of the p53 codon 72 polymorphism between endometriosis cases and controls in this population. The endometriosis cases with severe disease only were also evaluated, but no significant difference was observed in the frequency of the polymorphism between this subgroup and the controls.

CONCLUSION

Our findings suggest that the p53 codon 72 polymorphism is unlikely to be associated with endometriosis in Japanese women.

Bonafide, type-specific human papillomavirus persistence among HIV-positive pregnant women: predictive value for cytological abnormalities, a longitudinal cohort study

This study investigated the rate of human papillomavirus (HPV) persistence, associated risk factors, and predictors of cytological alteration outcomes in a cohort of human immunodeficiency virus-infected pregnant women over an 18-month period. HPV was typed through L1 gene sequencing in cervical smears collected during gestation and at 12 months after delivery. Outcomes were defined as nonpersistence (clearance of the HPV in the 2nd sample), re-infection (detection of different types of HPV in the 2 samples), and type-specific HPV persistence (the same HPV type found in both samples). An unfavourable cytological outcome was considered when the second exam showed progression to squamous intraepithelial lesion or high squamous intraepithelial lesion. Ninety patients were studied. HPV DNA persistence occurred in 50% of the cases composed of type-specific persistence (30%) or re-infection (20%). A low CD4⁺T-cell count at entry was a risk factor for type-specific, re-infection, or HPV DNA persistence. The odds ratio (OR) was almost three times higher in the type-specific group when compared with the re-infection group (OR = 2.8; 95% confidence interval: 0.43-22.79). Our findings show that bonafide (type-specific) HPV persistence is a stronger predictor for the development of cytological abnormalities, highlighting the need for HPV typing as opposed to HPV DNA testing in the clinical setting.

Study of a functional polymorphism in thep53 gene in systemic lupus erythematosus: lack of replication in a Spanish population

The aim of this study was to assess the possible association between the p53 suppressor gene codon 72 polymorphism and systemic lupus erythematosus (SLE). Our study population consisted of 513 SLE patients and 567 healthy controls. All the individuals were of Spanish Caucasian origin. Genotyping of the p53 codon 72 polymorphism was performed by allele-specific PCR. No statistically significant differences were observed between SLE patients and healthy controls when p53 codon 72 genotype and allele frequencies were compared. In addition, no evidence for association with clinical subfeatures of SLE was found. In conclusion, the p53 codon 72 polymorphism associated with SLE in a Korean population does not appear to play a major role in the susceptibility or severity of SLE in the Spanish population.

Microbiological diagnosis of human papilloma virus infection

Infection with human papillomavirus (HPV) is the leading cause of sexually transmitted infection worldwide. This virus generally causes benign lesions, such as genital warts, but persistent infection may lead to cervical cancer, anal cancer, vaginal cancer, and oropharyngeal cancer, although less frequently. Cervical cancer is a severe disease with a high mortality in some countries. Screening with cytology has been very successful in the last few years, but nowadays there are numerous studies that confirm that cytology should be replaced with the detection of HPV as a first line test in population based screening. There are several commercially available FDA approved tests for screening of cervical cancer. A new strategy, based on individual detection of the high risk genotypes HPV16 and HPV18, present in 70% of cervical cancer biopsies, has been proposed by some experts, and is going to be implemented in most countries in the future.

The Somatic Nature of Cancer Allows It to Affect Highly Constrained Genes

Cancer is special among genetic disorders in two major ways: first, cancer is a disease of the most basic of cellular functions, such as cell proliferation, differentiation, and the maintenance of genomic integrity. Second, in contrast to most genetic disorders that are mediated by germline (hereditary) mutations, cancer is largely a somatic disease. Here we show that these two traits are not detached and that it is the somatic nature of cancer that allows it to affect the most basic of cellular functions. We begin by demonstrating that cancer genes are both more functionally central (as measured by their patterns of expression and protein interaction) and more evolutionarily constrained than non-cancer genetic disease genes. We then compare genes that are only modified somatically in cancer (hereinafter referred to as “somatic cancer genes”) to those that can also be modified in a hereditary manner, contributing to cancer development (hereinafter referred to as “hereditary cancer genes”). We show that both somatic and hereditary cancer genes are much more functionally central than genes contributing to non-cancer genetic disorders. At the same time, hereditary cancer genes are only as constrained as non-cancer hereditary disease genes, while somatic cancer genes tend to be much more constrained in evolution. Thus, it appears that it is the somatic nature of cancer that allows it to modify the most constrained genes and, therefore, affect the most basic of cellular functions.

Genetic variants in cell cycle control pathway confer susceptibility to aggressive prostate carcinoma

BACKGROUND

Because a significant number of patients with prostate cancer (PCa) are diagnosed with disease unlikely to cause harm, genetic markers associated with clinically aggressive PCa have potential clinical utility. Since cell cycle checkpoint dysregulation is crucial for the development and progression of cancer, we tested the hypothesis that common germ-line variants within cell cycle genes were associated with aggressive PCa.

METHODS

Via a two-stage design, 364 common sequence variants in 88 genes were tested. The initial stage consisted of 258 aggressive PCa patients and 442 controls, and the second stage added 384 aggressive PCa Patients and 463 controls. European-American and African-American samples were analyzed separately. In the first stage, SNPs were typed by Illumina Goldengate assay while in the second stage SNPs were typed by Pyrosequencing assays. Genotype frequencies between cases and controls were compared using logistical regression analysis with additive, dominant and recessive models.

RESULTS

Eleven variants within 10 genes (CCNC, CCND3, CCNG1, CCNT2, CDK6, MDM2, SKP2, WEE1, YWHAB, YWHAH) in the European-American population and nine variants in 7 genes (CCNG1, CDK2, CDK5, MDM2, RB1, SMAD3, TERF2) in the African-American population were found to be associated with aggressive PCa using at least one model. Of particular interest, CCNC (rs3380812) was associated with risk in European-American cohorts from both institutions. CDK2 (rs1045435) and CDK5 (rs2069459) were associated with risk in the African-American cohorts from both institutions. Lastly, variants within MDM2 and CCNG1 were protective for aggressive PCa in both ethnic groups.

CONCLUSIONS

This study confirms that polymorphisms within cell cycle genes are associated with clinically aggressive PCa. Validation of these markers in additional populations is necessary, but these markers may help identify patients at risk for potentially lethal carcinoma.

EXPRESSION OF OCT-4, P53, P16 AND KI-67, WITH HPV ASSOCIATED PRECANCER AND CANCER OF THE CERVIX

The pathology of cervical HPV infection is detected by three types of epithelial-mesenchymal spheroidal structures: reparative, neoplastic and cancerous involved in reparation processes and in tumor growth. Cancer spheroids are different from neoplastic not only larger in size but also a tendency to merge, and high expression of p53. Expression of tumor markers p53, p16 and Ki-67 could be used in the early differential diagnosis of precancer and squamous cell carcinoma of the cervix.

Systematic meta-analyses and field synopsis of genetic association studies in colorectal adenomas

BACKGROUND

Low penetrance genetic variants, primarily single nucleotide polymorphisms, have substantial influence on colorectal cancer (CRC) susceptibility. Most CRCs develop from colorectal adenomas (CRA). Here we report the first comprehensive field synopsis that catalogues all genetic association studies on CRA, with a parallel online database [http://www.chs.med.ed.ac.uk/CRAgene/].

METHODS

We performed a systematic review, reviewing 9750 titles, and then extracted data from 130 publications reporting on 181 polymorphisms in 74 genes. We conducted meta-analyses to derive summary effect estimates for 37 polymorphisms in 26 genes. We applied the Venice criteria and Bayesian False Discovery Probability (BFDP) to assess the levels of the credibility of associations.

RESULTS

We considered the association with the rs6983267 variant at 8q24 as 'highly credible', reaching genome-wide statistical significance in at least one meta-analysis model. We identified 'less credible' associations (higher heterogeneity, lower statistical power, BFDP > 0.02) with a further four variants of four independent genes: MTHFR c.677C>T p.A222V (rs1801133), TP53 c.215C>G p.R72P (rs1042522), NQO1 c.559C>T p.P187S (rs1800566), and NAT1 alleles imputed as fast acetylator genotypes. For the remaining 32 variants of 22 genes for which positive associations with CRA risk have been previously reported, the meta-analyses revealed no credible evidence to support these as true associations.

CONCLUSIONS

The limited number of credible associations between low penetrance genetic variants and CRA reflects the lower volume of evidence and associated lack of statistical power to detect associations of the magnitude typically observed for genetic variants and chronic diseases. The CRA gene database provides context for CRA genetic association data and will help inform future research directions.

Human Papillomavirus 16 Physical Status and the TP53 Codon 72 Polymorphism in Japanese HPV-Positive Oropharyngeal Cancer Patients

BACKGROUND

In human papillomavirus (HPV)-induced carcinogenesis, the arginine (Arg) allele of the TP53 codon 72 polymorphism binds more efficiently to the HPV E6 oncoprotein than the proline (Pro) allele. We investigated the physical status of HPV-16 DNA and the TP53 codon 72 polymorphism in oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

Tumor samples from 70 p16-positive OPSCC patients were tested for HPV-16 physical status by examining the E2 and E6 open reading frames. The TP53 codon 72 polymorphism was screened by direct sequencing.

RESULTS

Of 70 patients, 53 were E6 positive, 29 had integrated forms of HPV-16 DNA, and 24 had mixed or episomal forms. Furthermore, 44 carried the Arg/Arg or Arg/Pro genotype, 3 carried the Pro/Pro genotype, and in 6 patients we were unable to obtain sequencing data.

CONCLUSIONS

HPV-16 physical status was heterogeneous in our OPSCC patients. Most OPSCC patients had the TP53 Arg/Arg or Arg/Pro genotype.

Human Papillomavirus E6 Knockdown Restores Adenovirus Mediated-estrogen Response Element Linked p53 Gene Transfer in HeLa Cells

The p53 gene is inactivated by the human papillomavirus (HPV) E6 protein in the majority of cervical cancers. Treatment of HeLa S3 cells with siRNA for HPV E6 permitted adenovirus-mediated transduction of a p53 gene linked to an upstream estrogen response element (ERE). Our previous study in non-siRNA treated HHUA cells, which are derived from an endometrial cancer and express estrogen receptor β, showed enhancing effects of an upstream ERE on adenovirus-mediated p53 gene transduction. In HeLa S3 cells treated with siRNA for HPV E6, adenovirus-mediated transduction was enhanced by an upstream ERE linked to a p53 gene carrying a proline variant at codon 72, but not for a p53 gene with arginine variant at codon 72. Expression levels of p53 mRNA and Coxsackie/adenovirus receptor (CAR) mRNA after adenovirus-mediated transfer of an ERE-linked p53 gene (proline variant at codon 72) were higher compared with those after non-ERE-linked p53 gene transfer in siRNA-treated HeLa S3 cells. Western blot analysis showed lower β-tubulin levels and comparatively higher p53/β-tubulin or CAR /β-tubulin ratios in siRNA-treated HeLa S3 cells after adenovirus-mediated ERE-linked p53 gene (proline variant at codon 72) transfer compared with those in non-siRNA-treated cells. Apoptosis, as measured by annexin V binding, was higher after adenovirus-mediated ERE-linked p53 gene (proline variant at codon 72) transfer compared with that after non-ERE-linked p53 gene transfer in siRNA-treated cells.

Association of p53Pro72Arg (rs1042522) and MDM2309 (rs2279744) polymorphisms with risk for cervical intraepthelial lesions and cervical cancer development in Macedonian women

High risk Human Papillomavirus (HPV) is an important etiological factor in initiation of squamous intraepithelial lesions (SIL), but not enough for malignant progression to cervical cancer (CCa). Single nucleotide polymorphisms (SNPs): rs1042522 within the codon 72 of p53 and rs2279744 within MDM2 promoter gene are plausible factors for development of SIL or CCa conferring increased attenuation of p53 pathway. We investigated the association of these SNPs with the HPV positive SIL and CCa among women from the Republic of Macedonia. Using a multiplex PCR SNaPShot analysis we genotyped rs1042522 and rs2279744 in 131 HPV positive women with SIL or CCa and 110 HPV and cytologicaly negative controls subject. No significant difference in either genotype or allelic frequencies for rs1042522 and rs2279744 between cases and control was found. The stratification of patients on the basis of the lesion grade revealed lower frequency of CC genotype and C allele of rs1042522 in HSIL and CCa compared to LSIL [GG vs CC; p=0.001, OR=0.4; CG vs CC; p=0.04, OR=0.03 and CG+ GG vs CC; p=0.004, OR=0.2]. Additionally TT genotype and T allele of MDM2 309 showed significantly lower frequency in HSIL and CCa group then in LSIL [G vs T p=0.02, OR=0.52; GG vs TT; p=0.04, OR=0.29; ТТ vs ТG+GG; p=0.007, OR=0.34].The Arg variant of rs1042522 and T allele/TT genotype of rs2279744 are associated with progression to LSIL to HSIL or CCa and may be used as prediction markers in CCa management, but the clinical relevant warrants further validation in large and well-designed studies

Association between p53 status, human papillomavirus infection, and overall survival in advanced oral cancer after resection and combination systemic treatment

Our previous study on 75 cases of advanced oral squamous cell carcinomas (SCC) treated by neoadjuvant chemotherapy, radical surgery, and radiotherapy showed that overexpression of p53 of more than 50% indicated a strong probability of genetic mutation, and tumours that are characterised by this p53 pattern respond poorly to treatment and have a poor prognosis (p= 0.0001). We have studied the same cohort of patients retrospectively to investigate the incidence of human papillomavirus-16 (HPV16) infection, the relation to the overexpression or mutation of the p53 gene, and the association with overall survival. There were 57 men and 18 women, mean age 67 (range 57-72) years. HPV16 infectivity was found in 66 patients (88%) - 49/57 men (86%) and 17/18 women (94%). There was no significant difference between the sexes (p=0.32). The cumulative survival of the entire group after a follow-up of 38 months was 26% (SE 6.4). The log rank test indicated that the combination of HPV-16 infectivity and p53mutation was significantly related to prognosis (p=0.000). On the other hand HPV16 infectivity alone was not significantly related to prognosis (p=0.78) The incidence of HPV-16 infection decreased with increasing immune p53 expression (p=0.005), whereas that of the HPV16+p53mutation combination increased with increasing immune p53 expression (p=0.000). The results show the importance of the investigation of HPV and p53 expression to define prognosis in oral SCC.

Combined analysis of pri-miR-34b/c rs4938723 and TP53 Arg72Pro with cervical cancer risk

miR-34 family members can form a p53-miR-34 positive feedback loop and induce apoptosis, DNA repair, angiogenesis, and cell cycle arrest. We conducted a case-control study to examine whether two polymorphisms (i.e., rs4938723 in the promoter of pri-miR-34b/c and TP53 Arg72Pro) were linked to the carcinogenesis of cervical cancer among Chinese Han women. Genotypes of the two polymorphisms in 328 cervical cancer patients and 568 control subjects were determined by using a polymerase chain reaction-restriction fragment length polymorphism assay. We found a significantly increased cervical cancer risk in the pri-miR-34b/c rs4938723 under dominant and overdominant model (CT/CC vs. TT: adjusted OR = 1.34, 95 % CI = 1.01-1.77; CT vs. TT/CC: adjusted OR = 1.37, 95 % CI = 1.05-1.80, respectively). Increased cervical cancer risks were also found in the TP53 Arg72Pro under a heterozygous comparison and overdominant model (CG vs. GG: adjusted OR = 1.44, 95 % CI = 1.06-1.95; CG vs. GG/CC: adjusted OR = 1.47, 95 % CI = 1.12-1.94, respectively). Stratification analysis showed that patients carrying the pri-miR-34b/c rs4938723 CT genotype had a significantly increased risk for developing poorly differential status and clinical stage I. Moreover, increased cancer risks were observed for the TP53 Arg72Pro polymorphism in patients with poorly differential status, clinical stage II, and without lymph node metastasis. Combined analysis revealed that the genotypes of rs4938723 CT/CC and TP53 Arg72Pro CG/CC had an increased cervical cancer risk (OR = 2.21, 95 % CI = 1.38-3.53). These findings suggest that the pri-miR-34b/c rs4938723 and TP53 Arg72Pro polymorphisms may contribute to the genesis of cervical cancer.