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

Understanding the complexity of p53 in a new era of tumor suppression

p53 was discovered 45 years ago as an SV40 large T antigen binding protein, coded by the most frequently mutated TP53 gene in human cancers. As a transcription factor, p53 is tightly regulated by a rich network of post-translational modifications to execute its diverse functions in tumor suppression. Although early studies established p53-mediated cell-cycle arrest, apoptosis, and senescence as the classic barriers in cancer development, a growing number of new functions of p53 have been discovered and the scope of p53-mediated anti-tumor activity is largely expanded. Here, we review the complexity of different layers of p53 regulation, and the recent advance of the p53 pathway in metabolism, ferroptosis, immunity, and others that contribute to tumor suppression. We also discuss the challenge regarding how to activate p53 function specifically effective in inhibiting tumor growth without harming normal homeostasis for cancer therapy.

Human Papilloma Virus Positive Oropharyngeal Squamous Cell Carcinoma and the Immune System: Pathogenesis, Immunotherapy and Future Perspectives

Oropharyngeal squamous cell carcinoma (OPSCC), a subset of head and neck squamous cell carcinoma (HNSCC), involves the palatine tonsils, soft palate, base of tongue, and uvula, with the ability to spread to adjacent subsites. Personalized treatment strategies for Human Papillomavirus-associated squamous cell carcinoma of the oropharynx (HPV+OPSCC) are yet to be established. In this article, we summarise our current understanding of the pathogenesis of HPV+OPSCC, the intrinsic role of the immune system, current ICI clinical trials, and the potential role of small molecule immunotherapy in HPV+OPSCC.

DNA Double-Strand Break Response and Repair Gene Polymorphisms May Influence Therapy Results and Prognosis in Head and Neck Cancer Patients

Radiotherapy and cisplatin-based chemotherapy belong to the main treatment modalities for head and neck squamous cell carcinoma (HNSCC) and induce cancer cell death by generating DNA damage, including the most severe double-strand breaks (DSBs). Alterations in DSB response and repair genes may affect individual DNA repair capacity and treatment sensitivity, contributing to the therapy resistance and poor prognosis often observed in HNSCC. In this study, we investigated the association of a panel of single-nucleotide polymorphisms (SNPs) in 20 DSB signaling and repair genes with therapy results and prognosis in 505 HNSCC patients treated non-surgically with DNA damage-inducing therapies. In the multivariate analysis, there were a total of 14 variants associated with overall, locoregional recurrence-free or metastasis-free survival. Moreover, we identified 10 of these SNPs as independent predictors of therapy failure and unfavorable prognosis in the whole group or in two treatment subgroups. These were MRE11 rs2155209, XRCC5 rs828907, RAD51 rs1801321, rs12593359, LIG4 rs1805388, CHEK1 rs558351, TP53 rs1042522, ATM rs1801516, XRCC6 rs2267437 and NBN rs2735383. Only CHEK1 rs558351 remained statistically significant after correcting for multiple testing. These results suggest that specific germline variants related to DSB response and repair may be potential genetic modifiers of therapy effects and disease progression in HNSCC treated with radiotherapy and cisplatin-based chemoradiation.

BK polyomavirus: latency, reactivation, diseases and tumorigenesis

The identification of the first human polyomavirus BK (BKV) has been over half century, The previous epidemiological and phylogenetic studies suggest that BKV prevailed and co-evolved with humans, leading to high seroprevalence all over the world. In general, BKV stays latent and symptomless reactivation in healthy individuals. BKV has been mainly interlinked with BKV-associated nephropathy (BKVAN) in kidney-transplant recipients and hemorrhagic cystitis (HC) in hematopoietic stem cell transplant recipients (HSCTRs). However, the mechanisms underlying BKV latency and reactivation are not fully understood and lack of extensive debate. As Merkel cell polyomavirus (MCV) was identified as a pathogenic agent of malignant cutaneous cancer Merkel cell carcinoma (MCC) since 2008, linking BKV to tumorigenesis of urologic tumors raised concerns in the scientific community. In this review, we mainly focus on advances of mechanisms of BKV latency and reactivation, and BKV-associated diseases or tumorigenesis with systematical review of formerly published papers following the PRISMA guidelines. The potential tumorigenesis of BKV in two major types of cancers, head and neck cancer and urologic cancer, was systematically updated and discussed in depth. Besides, BKV may also play an infectious role contributing to HIV-associated salivary gland disease (HIVSGD) presentation. As more evidence indicates the key role of BKV in potential tumorigenesis, it is important to pay more attention on its etiology and pathogenicity in vitro and in vivo.

The TP53 Codon 72 Arginine Polymorphism Is Found with Increased TP53 Somatic Mutations in HPV(-) and in an Increased Percentage among HPV(+) Norwegian HNSCC Patients

BACKGROUND

Somatic TP53 mutations are frequent in head and neck squamous cell carcinoma (HNSCC) and are important pathogenic factors.

OBJECTIVE

To study TP53 mutations relative to the presence of human papillomavirus (HPV) in tumors in HNSCC patients.

METHODS

Using a custom-made next-generation sequencing (NGS) panel on formalin-fixed, paraffin-embedded tumor tissue, we analyzed somatic TP53 mutations and the TP53 single-nucleotide polymorphism (SNP) codon 72 (P72R; rs1042522) (proline → arginine) from 104 patients with HNSCC.

RESULTS

Only 2 of 44 patients with HPV-positive (HPV(+)) HNSCC had a TP53 somatic mutation, as opposed to 42/60 HPV-negative (HPV(-)) HNSCC patients (p < 0.001). Forty-five different TP53 somatic mutations were detected. Furthermore, in HPV(-) patients, we determined an 80% prevalence of somatic TP53 mutations in the TP53 R72 polymorphism cohort versus 40% in the TP53 P72 cohort (p = 0.001). A higher percentage of patients with oral cavity SCC had TP53 mutations than HPV(-) oropharyngeal (OP) SCC patients (p = 0.012). Furthermore, 39/44 HPV(+) tumor patients harbored the TP53 R72 polymorphism in contrast to 42/60 patients in the HPV(-) group (p = 0.024).

CONCLUSIONS

Our observations show that TP53 R72 polymorphism is associated with a tumor being HPV(+). We also report a higher percentage of somatic TP53 mutations with R72 than P72 in HPV(-) HNSCC patients.

Molecular Heterogeneity of Cervical Cancer Among Different Ethnic/Racial Populations

The study aimed to find differential gene mutation profile and gene expression status among different ethnic/racial human populations relevant for cervical cancer pathogenesis. The study was based on freely available datasets of The Cancer Genome Atlas (TCGA) of cervical cancer samples in Genomic Data Commons (GDC) data portal. We identified that choline metabolism in cancer and Ras signaling pathways were significantly associated with the Hispanic and Latino group of cervical cancer patients. In these pathways, mutations in the PIK3CA gene, especially E545K, were significantly associated with the Hispanic and LATINO group. We found that AFF3 gene mutation was associated with downregulation of its expression only among the White racial category of cervical cancer cases. Additionally, hypomethylation of the CpG position in the S shore region of the PM20D1 gene was associated with overexpression among the Asian category of cervical cancer cases. Heterogeneity of the molecular profile of AFF3 and PM20D1 gene among racial groups reflects the potential of differential targeted therapy of cervical cancer.

Human Papillomavirus Infection and Oropharyngeal and Gastrointestinal Cancers: A Causal Relationship?

The human papillomavirus (HPV) is one of the most common sexually transmitted infections worldwide. The risk of being infected at least once in a lifetime among both men and women is estimated to be 50%. Although the majority of HPV infections are asymptomatic and improve within 2 years, approximately 10% of individuals develop a persistent infection and have an increased risk of developing carcinomas. The association of HPV and genital cancer is well established. However, there is evidence that HPV may also be associated with other cancers, including those of the gastrointestinal system. The aim of this review is to organize the current evidence of associations between HPV infections and oropharyngeal and gastrointestinal cancers, including the following: oropharyngeal, esophageal, gastric, colorectal, and anal cancers. A comprehensive review of the most up-to-date medical literature concluded that an HPV infection might have a role in the oncogenesis of gastrointestinal tract cancers. HPV may have a causal relationship with oropharyngeal and esophageal squamous cell cancers. However, the association between HPV and gastric and colorectal cancers is weaker. The development of cancer in the oropharyngeal and gastrointestinal tract is usually multifactorial, with HPV having a role in at least a subset of these cancers. HPV infections pose a big challenge due to their burden of infection and their oncogenic potential.

Associations of MDM2 rs2279744 and TP53 rs1042522 polymorphisms with cervical cancer risk: A meta-analysis and systematic review

Background

Although the association between MDM2 rs2279744 and TP53 rs1042522 polymorphisms and cervical cancer has been reported, the results of its correlation were contradictory. Thus, we conducted a meta-analysis to precisely verify the relationships between MDM2 rs2279744 and TP53 rs1042522 polymorphisms and cervical cancer.

Methods

We thoroughly searched the PubMed, Web of Science, Embase, and Scopus databases for all potential articles from inception to June 2022 and used R Version 4.1.2 and STATA software 12.0 for the meta-analysis. The odds ratios (ORs), 95% confidence intervals (CIs) and 95% prediction intervals (PIs) were calculated to evaluate the associations. Subgroup analyses stratified by ethnicity, source of control, quality score and adjustment were further conducted to assess the relationship between MDM2 rs2279744 and TP53 rs1042522 polymorphisms and cervical cancer.

Results

A total of 30 case-control studies involving 5025 cases and 6680 controls were included. All the included studies were population-based or hospital-based studies. The overall analysis showed that MDM2 rs2279744 polymorphism was closely related to an increased risk of cervical cancer in the recessive model (GG vs GT + TT: OR = 1.602, 95% CI: 1.077-2.383, P = 0.020) and homozygote model (GG vs TT: OR = 1.469, 95% CI: 1.031-2.095, P = 0.033, 95% PI: 0.516-4.184). A significant correlation between TP53 rs1042522 polymorphism and cervical cancer was observed in two models (CC + CG vs GG: OR = 1.759, 95% CI: 1.192-2.596, P = 0.004, 95% PI: 0.474-6.533; GG vs CC: OR = 2.442, 95% CI: 1.433-4.162, P = 0.001, 95% PI: 0.456-13.071).

Conclusions

This meta-analysis revealed that MDM2 SNP309T&gt;G and TP53 rs1042522 C&gt;G polymorphisms were associated with the increased risk of cervical cancer.

Association between ТР53, MDM2 and NQO1 gene polymorphisms and viral load among women with human papillomavirus

The risk of cervical cancer is caused by persistent human papillomavirus (HPV) infection. Cervical cancer is the most frequent cancer among women. Our purpose was to investigate the association between TP53 215C>G (Pro72Arg), MDM2 -410T>G, and NQO1 609C>T gene polymorphisms with a high HPV load and the inf luence of gene-gene interactions on prolonged HPV infection. Eighty-nine women with a high HPV viral load and 114 healthy women were involved in a case–control study. Genotyping for TP53 215C>G (Pro72Arg) and MDM2 -410T>G SNPs was carried out by allele-specif ic PCR and genotyping for NQO1 609C>T was performed by a TaqMan assay. Quantitative analysis of HPV DNA was performed by AmpliSens® HPV HCR screen-titer-FRT test system. Gene-gene interactions were analyzed using the multifactor dimensionality reduction (MDR) method. The study of separate SNPs of MDM2 -410T>G and NQO1 609C>T genes did not reveal any statistically signif icant difference in genotype and allele frequencies among women within the two groups. The frequency of the 215G (72Arg) allele and 215GG (72Arg/ Arg) genotype of the TP53 gene was signif icantly higher in the case group than in the control group (OR = 1.74, 95 % CI = 1.10–2.73; p = 0.02 and OR = 1.97, 95 % CI = 1.13–3.46; p = 0.04, respectively). MDR analysis showed the signif icance of intergenic interactions of the three studied loci TP53 (rs1042522) – MDM2 (rs2279744) – NQO1 (rs1800566) for the formation of a high HPV load (OR = 3.05, 95 % CI = 1.73–5.46; p = 0.0001).

A Prospective Cohort Study of Biomarkers in Squamous Cell Carcinoma of the Anal Canal (SCCAC) and their Influence on Treatment Outcomes

Background: Although Chemoradiation (CRT) is the curative treatment for SCCAC, many patients present primary resistance. Since it is a rare tumor, response predictors remain unknown.

Methods: We performed a prospective cohort study to evaluate biomarkers associated with CRT response, progression-free survival (PFS), and overall survival (OS). The primary endpoint was response at 6 months (m). Tumor DNA and HPV were analyzed by next-generation sequencing, while KI-67 and PD-L1 by immunohistochemistry in tumor tissue.

Results: Seventy-eight patients were recruited between October/2011 and December/2015, and 75 were response evaluable. The median age was 57 years, 65% (n=49) were stage III and 12% (n=9) were HIV positive (HIV+). At 6m, 62.7% (n=47) presented CR. On multivariate analyses, stage II patients were 4.7 more likely to achieve response than stage III (OR, 4.70; 95%CI, 1.36-16.30; p=0.015). HIV+ was associated with a worse response (OR, 5.72; 95%CI, 2.5-13.0; p<0.001). 5-year PFS and OS rates were 63.3% and 76.4%, respectively, with a median follow up of 66m. On multivariate analyses, older age (HR 1.06, p=0.022, 95%IC 1.01-1.11) and absence of CR at 6m (HR 3.36, p=0.007, 95%IC 1.39-8.09) were associated with inferior OS. The 5-year OS rate was 62.5% in HIV+ group compared to 78% among HIV- pts, although this difference was not statistically significant (p=0.4). PIK3CA, MET and TP53 mutations, HPV, Ki-67 expression, and PD-L1 expression, were not associated with PFS and OS.

Conclusions: Clinical stage III and HIV+ were associated with worse response to CRT at 6m. The absence of CR was the main factor associated with poor 5-year OS.

HPV16 E6 Promotes the Progression of HPV Infection-Associated Cervical Cancer by Upregulating Glucose-6-Phosphate Dehydrogenase Expression

Cervical cancer, which is significantly associated with high-risk human papillomavirus (HPV) infection, currently ranks the fourth most common cancer among women worldwide. Previous literature reported that the elevated expression of G6PD was significantly correlated with the occurrence and deterioration of human cervical cancer, especially with the cervical cancer with HPV16 and HPV18 infection. In this study, we verified that G6PD expression has a strong positive correlation with HPV16 E6 levels in cervical cancer tissues and cells. In addition, regulating the expression of HPV16 E6 significantly affected the proliferation, apoptosis, migration, and invasion in the cervical cancer HeLa cells, as well as the transcript and protein levels of G6PD. The luciferase reporter assay and ChIP assay proved that HPV16 E6 stimulated the transcription of G6PD mRNA and subsequently enhanced the expression of G6PD through directly binding to the specific sites in the promoter of G6PD. Our findings reveal that HPV16 E6 is a novel regulatory factor of G6PD. Furthermore, by regulating the expression of G6PD, HPV16 E6 might promote the proliferation and migration potential, and inhibit apoptosis of cervical cancer cells, which ultimately contributed to the progression and metastasis of cervical cancer.

At a Crossroads to Cancer: How p53-Induced Cell Fate Decisions Secure Genome Integrity

P53 is known as the most critical tumor suppressor and is often referred to as the guardian of our genome. More than 40 years after its discovery, we are still struggling to understand all molecular details on how this transcription factor prevents oncogenesis or how to leverage current knowledge about its function to improve cancer treatment. Multiple cues, including DNA-damage or mitotic errors, can lead to the stabilization and nuclear translocation of p53, initiating the expression of multiple target genes. These transcriptional programs may be cell-type- and stimulus-specific, as is their outcome that ultimately imposes a barrier to cellular transformation. Cell cycle arrest and cell death are two well-studied consequences of p53 activation, but, while being considered critical, they do not fully explain the consequences of p53 loss-of-function phenotypes in cancer. Here, we discuss how mitotic errors alert the p53 network and give an overview of multiple ways that p53 can trigger cell death. We argue that a comparative analysis of different types of p53 responses, elicited by different triggers in a time-resolved manner in well-defined model systems, is critical to understand the cell-type-specific cell fate induced by p53 upon its activation in order to resolve the remaining mystery of its tumor-suppressive function.

Vulvar carcinoma in Fanconi Anaemia: A case report with review of literature

Fanconi anaemia is a rare autosomal recessive disorder associated with bone marrow failure and congenital malformations. The impaired DNA repair pathways in Fanconi anaemia predispose patients to a high risk of cancers of squamous cell origin, particularly in the head and neck region. Cancers of the vagina and vulva are rare in Fanconi anaemia. Here, we report a case of a 44-year-old female with Fanconi anaemia who developed an ulcerated lesion on the clitoris that extended into the labia majora. A biopsy of the lesion showed well-differentiated squamous cell carcinoma. The patient was treated with wide local excision of the vulval lesion. The patient developed neutropenia post-procedure but recovered in one week time. We have followed up the patient regularly since the procedure. No further issues have been detected to date.

Human papillomavirus E6 and E7: What remains?

Decades of research on the human papillomavirus oncogenes, E6 and E7, have given us huge amounts of data on their expression, functions and structures. We know much about the very many cellular proteins and pathways that they influence in one way or another. However, much of this information is quite discrete, referring to one activity examined under one condition. It is now time to join the dots to try to understand a larger picture: how, where and when do all these interactions occur... and why? Examining these questions will also show how many of the yet obscure cellular processes work together for cellular and tissue homeostasis in health and disease.

Metabolic Reprogramming in Cancer: Role of HPV 16 Variants

Metabolic reprogramming is considered one of the hallmarks in cancer and is characterized by increased glycolysis and lactate production, even in the presence of oxygen, which leads the cancer cells to a process called “aerobic glycolysis” or “Warburg effect”. The E6 and E7 oncoproteins of human papillomavirus 16 (HPV 16) favor the Warburg effect through their interaction with a molecule that regulates cellular metabolism, such as p53, retinoblastoma protein (pRb), c-Myc, and hypoxia inducible factor 1α (HIF-1α). Besides, the impact of the E6 and E7 variants of HPV 16 on metabolic reprogramming through proteins such as HIF-1α may be related to their oncogenicity by favoring cellular metabolism modifications to satisfy the energy demands necessary for viral persistence and cancer development. This review will discuss the role of HPV 16 E6 and E7 variants in metabolic reprogramming and their contribution to developing and preserving the malignant phenotype of cancers associated with HPV 16 infection.

A Shared Susceptibility Locus in the p53 Gene for both Gastric and Esophageal Cancers in a Northwestern Chinese Population

Background: Upper gastrointestinal tract cancers are the leading causes of cancer-related deaths in Northwest China and they share many similarities in terms of histological type, risk factors, and genetic variants. We hypothesized that shared common single-nucleotide polymorphisms (SNPs) in the p53 pathway exist between patients with gastric and esophageal cancer (EC) patients. Materials and Methods: A case-control study to examine genetic variants in the p53 pathway was conducted with subjects from a high-incidence area for upper gastrointestinal cancers of China. Multiple logistic regression analyses were used to estimate the association of genotypes with gastric cancer and EC risks. Median survival was estimated by using the Kaplan-Meier method and compared by using the log-rank test. Results: Compared with the rs1042522 Pro allele, the rs1042522 Arg allele was associated with an increased risk of gastric cancer (1.810×) and an increased risk of EC (2.285×). The rs1042522 Arg allele carriers who also smoked or consumed alcohol had a further increased risk for gastric cancer odds ratios (OR_smoking = 2.422, OR_drinking = 5.152) and EC (OR_smoking = 5.310, OR_drinking = 8.359). No association was found between the rs1042522 genotypes and survival (p > 0.05). Conclusion: The p53 rs1042522 arg allele together with tobacco smoking and alcohol drinking, was associated with an increased risk, for gastric cancer and EC, but not the survival among northwestern Chinese patients. These associations warrant confirmatory studies.

APOBEC: A molecular driver in cervical cancer pathogenesis

Cervical cancer is one of the foremost common cancers in women. Human papillomavirus (HPV) infection remains a major risk factor of cervical cancer. In addition, numerous other genetic and epigenetic factors also are involved in the underlying pathogenesis of cervical cancer. Recently, it has been reported that apolipoprotein B mRNA editing enzyme catalytic polypeptide like (APOBEC), DNA-editing protein plays an important role in the molecular pathogenesis of cancer. Particularly, the APOBEC3 family was shown to induce tumor mutations by aberrant DNA editing mechanism. In general, APOBEC3 enzymes play a pivotal role in the deamination of cytidine to uridine in DNA and RNA to control diverse biological processes such as regulation of protein expression, innate immunity, and embryonic development. Innate antiviral activity of the APOBEC3 family members restrict retroviruses, endogenous retro-element, and DNA viruses including the HPV that is the leading risk factor for cervical cancer. This review briefly describes the pathogenesis of cervical cancer and discusses in detail the recent findings on the role of APOBEC in the molecular pathogenesis of cervical cancer.

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APOBEC enzymes deaminate cytidine to uridine and control diverse biological processes including viral restriction.

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APOBEC3, DNA/RNA-editing enzyme plays an important role in the molecular pathogenesis of cervical cancer.

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APOBEC3-mediated DNA editing leads to the accumulation of somatic mutations in tumors and HPV genome.

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Deregulation of APOBEC3 family genes cause genomic instability and result in drug resistance, and immune-evasion in tumors.

The role of single- and multi-walled carbon nanotube in breast cancer treatment

Numerous studies have been conducted to design new strategies for breast cancer treatment. Past studies have shown a wide range of carbon-nanomaterials properties, such as single- and multi-walled carbon nanotubes (SWCNTs and MWCNTs) in breast cancer diagnosis and treatment. In this regard, the current study aims to review the role of both SWCNTs and MWCNTs in breast cancer treatment and diagnosis. For reaching this goal, we reviewed the literature by using various searching engines such as Scopus, PubMed, Google Scholar, Web of Science and MEDLINE. This comprehensive review showed that CNTs could dramatically improve breast cancer treatment and could be used as a novel modality to increase diagnostic accuracy; however, no clinical studies have been conducted based on CNTs. In addition, the literature review demonstrates a lack of enough studies to evaluate the side effects of using CNTs.

Exploring the p53 connection of cervical cancer pathogenesis involving north-east Indian patients

BACKGROUND

As per WHO, Cervical cancer (CaCx) is a global issue, being the fourth common cancer in women with incidence rate of 13.1 per 1 lakh women globally and accounting for 311000 deaths in the year 2018 itself globally. The molecular pathogenesis in Human papillomavirus (HPV) infected cases is inconclusive. The detection of molecular factors leading to progression of CaCx can be important in the diagnosis and management of the disease. p53 a known tumor suppressor gene having a regulative role in cell cycle has been highlighted as key factor in the prevention of cancer but its significance in CaCx cases has been variably documented. The present study therefore targeted to evaluate the significance of p53 profile in CaCx cases in ethnically distinct northeast Indian population.

METHODS

Blood and Tissue samples (N = 85) of cervical cancer patients were collected and screening for HPV was performed using PCR. Thereafter the differential mRNA expression(qPCR), Immunohistochemistry, Mutation (PCR direct sequencing method) of p53 was studied. Further p53 epigenetic profiling was done by Methylation specific PCR (MS-PCR) and western blotting by using p53 acetylation specific antibodies.

RESULTS

Our findings revealed that the downregulation of p53 was associated with the progression of disease and the variation in downregulation based on p53 polymorphism was observed. Further hypermethylation and deacetylation of p53 was also found to be associated with the pathogenesis of CaCx. The downregulated expression and hypermethylation of p53 in lower grade of CaCx, together established its association with the progression of CaCx from lower to severe grade.

CONCLUSION

Therefore, in CaCx patients of northeast Indian population, malfunctioning of p53 is found to have significant role in cervical cancer progression.

Both p53 codon 72 Arg/Arg and pro/Arg genotypes in glioblastoma multiforme are associated with a better prognosis in bevacizumab treatment

BACKGROUND

It has previously been shown that bevacizumab, when added to chemotherapy, improved overall survival in several cancers. In glioblastoma multiforme (GBM), bevacizumab increased progression-free survival and it is widely used for tumor recurrence, though it has failed to improve overall survival (OS) in controlled trials. However, an effective biomarker for predicting the prognosis of bevacizumab treatment has yet to be identified. This study, therefore, aimed to retrospectively analyze the polymorphisms of p53 codon 72 and the clinical characteristics of GBM specimens from Taiwanese patients.

METHODS

The polymorphisms of p53 codon 72 in 99 patients with GBM treated at Taichung Veterans General Hospital in Taiwan from 2007 to 2017 were analyzed using direct DNA sequencing and PCR-RFLP analysis.

RESULTS

We found that among these GBM patients, the distribution of codon 72 polymorphisms was 28.3% for proline homozygotes (Pro/Pro), 38.4% for arginine homozygotes (Arg/Arg), and 33.3% for proline/arginine heterozygotes (Pro/Arg). Although the polymorphisms of p53 codon 72 were not directly associated with the overall survival of GBM, both the Arg/Arg and Arg/Pro genotypes were associated with significant benefits in terms of overall survival in patients treated with CCRT plus bevacizumab compared to patients treated with CCRT alone.

CONCLUSIONS

This pilot study suggests that both the Arg/Arg and Arg/Pro genotypes of p53 codon 72 polymorphism may have value as independent prognostic or predictive parameters for bevacizumab treatment response and failure. Relatedly, the results of the study further demonstrate the utility of stratifying GBM patients according to bevacizumab sensitivity.

Persistent High-Risk HPV Infection and Molecular Changes Related to the Development of Cervical Cancer

This article is a preliminary investigational study that is aimed at giving hints about the interesting biomarkers involved in the transition process from low-grade cervix lesion to invasive cervical cancer. Our study focuses on the risk factors and tumour molecular changes in one patient. First in 1986, she was diagnosed a preinvasive cervix lesion. Then, 16 years later, she was diagnosed an invasive cervical cancer. The 2002 diagnosis was a squamous cell carcinoma of the cervix, stage IIIB (FIGO), whereas in 1986, she had been diagnosed a high-grade squamous intraepithelial cervical lesion. Retrospectively, the analysis of samples of preneoplastic lesions and invasive cervical cancer confirmed the histopathological diagnoses and detected the presence of HPV type and HPV-16 variants, as well as the overexpression of proteins such as hTERT, IGF1Rα, IGF1Rβ, CAIX, and GLUT1. Finally, the Arg72Pro polymorphism was detected in TP53. The role of high-risk HPV and HPV-16 variants and of hTERT, IGF1Rα, IGF1Rβ, CAIX, and GLUT1 variations seemed confirmed in the development and progression of cervical cancer. As a result, analyzing the molecular changes in one and same tumour that progresses from a low-grade cervix lesion to invasive cervical cancer could provide valuable information in order to improve detection, diagnosis, and treatment in the future.

Common genetic variants in the TP53 pathway and their impact on cancer

The TP53 gene is well known to be the most frequently mutated gene in human cancer. In addition to mutations, there are > 20 different coding region single-nucleotide polymorphisms (SNPs) in the TP53 gene, as well as SNPs in MDM2, the negative regulator of p53. Several of these SNPs are known to alter p53 pathway function. This makes p53 rather unique among cancer-critical genes, e.g. the coding regions of other cancer-critical genes like Ha-Ras, RB, and PI3KCA do not have non-synonymous coding region SNPs that alter their function in cancer. The next frontier in p53 biology will consist of probing which of these coding region SNPs are moderately or strongly pathogenic and whether they influence cancer risk and the efficacy of cancer therapy. The challenge after that will consist of determining whether we can tailor chemotherapy to correct the defects for each of these variants. Here we review the SNPs in TP53 and MDM2 that show the most significant impact on cancer and other diseases. We also propose avenues for how this information can be used to better inform personalized medicine approaches to cancer and other diseases.

Association of TP53 rs1042522 C>G and miR-34b/c rs4938723 T>C polymorphisms with hepatoblastoma susceptibility: A seven-center case-control study

BACKGROUND

Hepatoblastoma is a rare malignancy originating from pluripotent stem cells with unknown etiology. An understanding of the etiology in pediatric hepatoblastoma has been hampered by the unavailability of sufficient patient samples. To date, only a few epidemiological studies with small sample sizes have been performed investigating risk factors for hepatoblastoma. TP53 and pri-miR-34b/c genes are implicated in the tumorigenesis, yet the role of their polymorphisms in hepatoblastoma susceptibility remains unknown.

METHODS

We conducted a seven-center case-control study to explore the genetic variants predisposing to hepatoblastoma susceptibility. In our study, we genotyped two functional polymorphisms, the TP53 rs1042522 C>G (Arg72Pro) and miR-34b/c rs4938723 T>C, in 313 cases and 1446 controls using the TaqMan method.

RESULTS

Single loci analysis showed that neither TP53 rs1042522 C>G, nor miR-34b/c rs4938723 T>C significantly modified hepatoblastoma risk. In the stratification analysis, we identified that the miR-34b/c rs4938723 TC/CC genotypes were associated with a decreased risk in patients with clinical stages III + IV hepatoblastoma (adjusted odds ratio = 0.53, 95% confidence interval = 0.33-0.84, P=0.007] compared to the rs4938723 TT genotype. Subsequent analysis further showed that the combination of TP53 and miR-34b/c variant genotypes had no impact on susceptibility hepatoblastoma.

CONCLUSIONS

Taken together, TP53 rs1042522 C>G and miR-34b/c rs4938723 T>C may not confer hepatoblastoma susceptibility. These findings may aid in our understanding of the genetic etiology of hepatoblastoma.

TP53 genetic polymorphisms and susceptibility to cervical cancer in Bangladeshi women: a case-control study

Pharmacogenetic study of TP53 gene polymorphisms has not been conducted extensively in cervical cancer. The aim of this study was to assesses the TP53 codon 72 and codon 47 polymorphisms and their relation to cervical cancer risk in Bangladeshi women. 134 cervical cancer patients and 102 age matched healthy controls were included from two institutions in Bangladesh. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used for genotyping two TP53 single nucleotide polymorphisms (codon 72 and codon 47) in patients and controls. The results indicate that the TP53 Arg/Pro heterozygosity (adjusted OR   2.32, 95% CI  1.28-4.34, p = 0.01), Pro/Pro mutant homozygosity (adjusted OR  4.15, 95% CI  1.75-9.86, p = 0.001), along with the combined genotype (Arg/Pro + Pro/Pro) (adjusted OR  2.83, 95% CI  1.61-4.97, p < 0.001) significantly increases the risk of cervical cancer. Moreover, the cervical cancer patients with a first-degree relative cancer patient possesses 4.45 folds more risk (p = 0.019) of carrying a proline allele in codon 72 of the TP53 gene compared to those patients who do not have any first-degree relative with cancer. Finally, polymorphism in the codon 47 of the TP53 gene did not significantly increase the risk of cervical cancer in Bangladeshi women. To conclude, this is the first study to identify that polymorphism in the TP53 codon 72 significantly increases the risk of cervical cancer in a female population in Bangladesh.

TP53 Arg72Pro polymorphism and neuroblastoma susceptibility in eastern Chinese children: a three-center case-control study

TP53 is a tumor suppressor gene that regulates cell growth, apoptosis and DNA repair. Previous studies have reported the contribution of TP53 Arg72Pro (rs1042522 C>G) polymorphism to pathogenesis of multiple tumors. Hence, we evaluated the association between this polymorphism and neuroblastoma susceptibility in eastern Chinese children. The Taqman genotyping assay was performed in 373 patients and 762 controls. Odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the strength of the association. No significant association was found between the TP53 gene rs1042522 C>G polymorphism and neuroblastoma susceptibility in the overall analysis (CG vs. CC: adjusted OR = 0.92, 95% CI = 0.70-1.22, P=0.567; GG vs. CC: adjusted OR = 0.99, 95% CI = 0.69-1.42, P=0.947; CG/GG vs. CC: adjusted OR = 0.94, 95% CI = 0.72-1.23, P=0.639; or GG vs. CC/CG: adjusted OR = 1.04, 95% CI = 0.75-1.43, P=0.814) and stratified analysis by age, gender, sites of origin, and clinical stages. The TP53 gene rs1042522 C>G polymorphism may not be a risk factor for neuroblastoma in eastern Chinese children. Future studies are needed to confirm this negative result and to reveal additional functional TP53 variants predisposing to neuroblastoma.

Association of TP53 rs1042522 with cervical cancer in the sub-Saharan African population: a meta-analysis

OBJECTIVE

TP53 plays a crucial role in preventing cancer development. Previous studies in sub-Saharan Africa (SSA) reported inconclusive findings for the association of the TP53 rs1042522 C > G variant with cervical cancer. We therefore performed a meta-analysis to summarise this association in the SSA population.

METHODS

Online databases were searched to identify suitable articles according to the PRISMA guidelines. We included studies published in English or French that provided the sample sizes and genotype counts for both cases and controls and evaluated the association between TP53 rs1042522 and cervical cancer in the SSA population. A fixed-effect model was used to calculate the pooled odds ratio (OR) and 95% confidence intervals (95% CIs).

RESULTS

A total of 699 cervical cancer cases and 1008 controls from eight studies in SSA were included in this meta-analysis. Women harbouring the variant G allele of the TP53 rs1042522 were at increased risk of cervical cancer in allelic (G vs. C; OR = 1.30, 95% Cl = 1.12-1.50), homozygous (GG vs. CC; OR = 1.62, 95% CI = 1.20-2.19) and recessive (GG vs. CG + GG; OR = 1.74, 95% CI = 1.34-2.25) genetic models. However, the dominant genetic model (CG + GG vs. CC; OR = 1.20, 95% CI = 0.96-1.48) was not significantly associated with cervical cancer.

CONCLUSIONS

Our meta-analysis revealed that harbouring variant G allele of TP53 rs1042522 is associated with cervical cancer risk in the SSA population.

Estrogen Receptors and Ubiquitin Proteasome System: Mutual Regulation

This review provides information on the structure of estrogen receptors (ERs), their localization and functions in mammalian cells. Additionally, the structure of proteasomes and mechanisms of protein ubiquitination and cleavage are described. According to the modern concept, the ubiquitin proteasome system (UPS) is involved in the regulation of the activity of ERs in several ways. First, UPS performs the ubiquitination of ERs with a change in their functional activity. Second, UPS degrades ERs and their transcriptional regulators. Third, UPS affects the expression of ER genes. In addition, the opportunity of the regulation of proteasome functioning by ERs—in particular, the expression of immune proteasomes—is discussed. Understanding the complex mechanisms underlying the regulation of ERs and proteasomes has great prospects for the development of new therapeutic agents that can make a significant contribution to the treatment of diseases associated with the impaired function of these biomolecules.

HPV Oncoproteins and the Ubiquitin Proteasome System: A Signature of Malignancy?

Human papillomavirus (HPV) E6 and E7 oncoproteins are critical for development and maintenance of the malignant phenotype in HPV-induced cancers. These two viral oncoproteins interfere with a plethora of cellular pathways, including the regulation of cell cycle and the control of apoptosis, which are critical in maintaining normal cellular functions. E6 and E7 bind directly with certain components of the Ubiquitin Proteasome System (UPS), enabling them to manipulate a number of important cellular pathways. These activities are the means by which HPV establishes an environment supporting the normal viral life cycle, however in some instances they can also lead to the development of malignancy. In this review, we have discussed how E6 and E7 oncoproteins from alpha and beta HPV types interact with the components of the UPS, and how this interplay contributes to the development of cancer.

Protein Oxidative Damage in UV-Related Skin Cancer and Dysplastic Lesions Contributes to Neoplastic Promotion and Progression

The ultraviolet (UV) component of solar radiation is the major driving force of skin carcinogenesis. Most of studies on UV carcinogenesis actually focus on DNA damage while their proteome-damaging ability and its contribution to skin carcinogenesis have remained largely underexplored. A redox proteomic analysis of oxidized proteins in solar-induced neoplastic skin lesion and perilesional areas has been conducted showing that the protein oxidative burden mostly concerns a selected number of proteins participating to a defined set of functions, namely: chaperoning and stress response; protein folding/refolding and protein quality control; proteasomal function; DNA damage repair; protein- and vesicle-trafficking; cell architecture, adhesion/extra-cellular matrix (ECM) interaction; proliferation/oncosuppression; apoptosis/survival, all of them ultimately concurring either to structural damage repair or to damage detoxication and stress response. In peri-neoplastic areas the oxidative alterations are conducive to the persistence of genetic alterations, dysfunctional apoptosis surveillance, and a disrupted extracellular environment, thus creating the condition for transformant clones to establish, expand and progress. A comparatively lower burden of oxidative damage is observed in neoplastic areas. Such a finding can reflect an adaptive selection of best fitting clones to the sharply pro-oxidant neoplastic environment. In this context the DNA damage response appears severely perturbed, thus sustaining an increased genomic instability and an accelerated rate of neoplastic evolution. In conclusion UV radiation, in addition to being a cancer-initiating agent, can act, through protein oxidation, as a cancer-promoting agent and as an inducer of genomic instability concurring with the neoplastic progression of established lesions.

Human papillomavirus type 18 oncoproteins exert their oncogenicity in esophageal and tongue squamous cell carcinoma cell lines distinctly

Background

Increasing evidence indicates an etiological role of human papillomavirus (HPV) in head and neck cancers, particularly oropharyngeal squamous cell carcinoma (OPSCC). However, the association between HPV and other cancers, including esophageal and tongue remains unclear. This study delineated the molecular characteristics of HPV18 E6 and E7 in esophageal (EC109 and EC9706) and tongue (Tca83) cancer cell lines with reference to cervical cancer (HeLa).

Methods

We analysed the HPV transcription profiles of esophageal and tongue cancer cells through Next-generation RNA sequencing, and the role of HPV18 E6 and E7 in these cells was assessed via siRNA approach, Western blotting and immunofluorescence assays.

Results

Overall, the HPV transcription profiles of esophageal and tongue cancer cells mimicked that of cervical cancer cells, with notable disruption of E2, and expression of E6, spliced E6 (E6^*), E7, E1 and L1 transcripts. As with cervical cancer cells, p53 and its downstream transactivation target, p21, were found to be the major targets of E6 in esophageal and tongue cancer cell lines. Intriguingly, E7 preferentially targeted p130 in the two esophageal cancer cell lines, instead of pRb as in cervical cancer. Tca83 exhibited an E7 to E6 transcript ratio comparable to HeLa (cervix), targeted the ERK1/2 and MMP2 pathways, and was dependent on E6 and E7 to survive and proliferate. In contrast, both the esophageal cancer cell lines were distinct from HeLa in these aspects.

Conclusions

This is the first study that delineates transcript expression and protein interaction of HPV18 E6 and E7 in esophageal and tongue cancer cell lines, suggesting that HPV plays a role in inducing these cancers, albeit via distinct pathways than those observed in cervical cancer.

The Dilemma of TP53 Codon 72 Polymorphism (rs1042522) and Breast Cancer Risk: A Case-Control Study and Meta-Analysis in The Iranian Population

Objective

Mutations of TP53 as a tumor suppressor gene are frequently observed in different types of cancer. A codon 72 polymorphism located on exon 4 with two alleles encoding either Proline (CCC) or Arginine (CGC) has been indicated as a common variation in association with cancers. Controversial results have been reported regarding the association of allelic polymorphism of codon 72 of TP53 gene and breast cancer risk in Iranian patients. Therefore, a case-control study was designed. A meta-analysis was also carried out to provide evidence of association between this variation and breast cancer in Iran, based on all available published data.

Materials and Methods

In this case-control study, blood sample of 622 participants, including 308 breast cancer cases and 314 controls were collected. Genotyping for rs1042522 was conducted by Allele Specific polymerase chain reaction (AS-PCR). In order to set a meta-analysis study, PubMed, Scopus and ISI Web of Knowledge and Persian databases were searched to explore relevant studies, published up to September 2018, containing information on TP53 polymorphism and the risk of breast cancer in Iran. Statistical analysis was performed using SPSS 16.0 and MetaGenyo.

Results

All retrieved available data as well as the results of our current study were consisted of 1965 breast cancer cases and 1999 healthy controls. No significant difference was observed in allele frequencies between groups (P=0.90) in our study. The cumulative results did not also show any association between rs1042522 and breast cancer risk on the dominant (P=0.61) and recessive (P=0.89) models.

Conclusion

These findings cannot support contribution of rs1042522 polymorphism to breast cancer risk in an Iranian population. Future larger studies may help confirm this finding with a greater power. .

Association of miR-34b/c rs4938723 and TP53 Arg72Pro Polymorphisms with Neuroblastoma Susceptibility: Evidence from Seven Centers

Neuroblastoma is a pediatric malignancy arising from the developing peripheral nervous system. p53 and downstream effector miR-34b/c have critical tumor suppressing functions. TP53 Arg72Pro (rs1042522 C > G) and miR-34b/c rs4938723 (T > C) polymorphisms have been known to modify cancer susceptibility. This study was performed to validate the association of these two polymorphisms and neuroblastoma risk with 819 cases and 1780 controls. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were used to assess the strength of the associations. False positive report possibility analysis was adopted to dissect out real significant associations from chance findings. We found that both TP53 Arg72Pro (CG/GG vs. CC: adjusted OR = 0.82, 95% CI = 0.69-0.98) and miR-34b/c rs4938723 (TC/CC vs. TT: adjusted OR = 0.64, 95% CI = 0.54-0.75) were associated with decreased neuroblastoma susceptibility. Stratify analyses further confirmed the protective effect among some subgroups. Moreover, subjects with variant alleles of both polymorphisms were associated with more significantly decreased neuroblastoma risk (CG/TC vs. CC/TT: adjusted OR = 0.38, 95% CI = 0.28-0.50; GG/TC vs. CC/TT: adjusted OR = 0.43, 95% CI = 0.30-0.63) than those carrying variant allele of either one polymorphism (CC/TC vs. CC/TT: adjusted OR = 0.51, 95% CI = 0.37-0.69; CG/TT vs. CC/TT: adjusted OR = 0.71, 95% CI = 0.55-0.92), suggesting cumulative effects of the polymorphisms. False positive report possibility analysis further verified that our findings are noteworthy. Overall, we confirmed that miR-34b/c rs4938723 and TP53 Arg72Pro conferred decreased neuroblastoma risk and two polymorphisms exerted stronger protective effects against neuroblastoma than either one alone.

Association of polymorphism TP53 Arg72Pro with radon-induced lung cancer in the Kazakh population

Lung cancer is a problem of great concern and one of the commonest cancer diseases worldwide and in the Republic of Kazakhstan in particular. Radon exposure is classified as the second most important cause of lung cancer. According to the experts, the contribution of natural sources to the average annual radiation dose of the Kazakh population currently stands at 80 %, including 50 % from radon. However, the effect of radon on human health in the Republic of Kazakhstan is almost unknown. The tumor suppressor gene TP53 is a key mediator of the DNA damage response cascade following cell exposure to ionizing radiation. The common polymorphism TP53 Arg72Pro (rs1042522) is a risk factor for lung cancer in the Asian population, but until now no genetic association studies have been done in the Kazakh population. No information on the synergistic carcinogenic effect of radon exposure and polymorphism TP53 Arg72Pro (rs1042522) is available either. This paper presents the results of the study of association between alteration in the TP53 gene and radon-induced lung cancer risk in the Kazakh population. Genetic association was assessed in a case-control study including 44 radon-exposed patients with lung cancer, 41 patients with lung cancer without radon exposure and 42 age/sex-matched healthy controls. We found that polymorphism TP53 Arg72Pro (rs1042522) was associated with lung cancer risk in the Kazakh population (OR = 6.95, 95 % CI = 2.41–20.05). Individuals with the Arg72Pro genotype also showed a significantly higher risk of radon-induced lung cancer (OR = 8.6, 95 % CI = 2.6–28.59).

Impact of MDM2, TP53 and P14ARF Polymorphisms on Endometrial Cancer Risk and Onset

BACKGROUND/AIM

The aim of this study was to determine the joint effect of single nucleotide polymorphisms (SNPs) of MDM2, TP53, and CDKN2A (P14ARF) genes on the onset and course of endometrial cancer (EC) in postmenopausal women.

MATERIALS AND METHODS

The study group consisted of 144 EC women and 50 non-cancer controls. MDM2 rs22279744, TP53 rs1042522, and P14ARF rs3088440, rs3731217, and rs3731245 SNPs were analysed.

RESULTS

The double-SNP combinations T-C, T-T, or T-G in MDM2 SNP 309 and P14ARF polymorphisms decreased EC risk. The triple-SNP combinations T-C-T, T-C-G, or T-T-G in MDM2 SNP and two P14ARF polymorphisms decreased EC risk. The multiple-SNP combination T-C-T-G in MDM2 and three P14ARF polymorphisms decreased EC risk. The G-Arg-C-T-G carriers were at increased EC risk, while the T-Arg-C-T-G carriers were at decreased EC risk.

CONCLUSION

MDM2 SNP309 plays a role in EC onset in postmenopausal women.

Establishment and characterization of patient-derived organoids from a young patient with cervical clear cell carcinoma

Cervical clear cell carcinoma (cCCC) constitutes an extremely rare subtype of cervical cancer. Consequently, its pathogenesis remains largely unknown, with no cell lines established from primary tumors. Here, we report the first establishment of cCCC organoids, from biopsy samples of a 23‐year‐old patient diagnosed with cCCC. By applying a protocol that we recently optimized for gynecological tumors, we were able to propagate a patient‐derived cell line (PDC) for more than 6 months as organoids. This PDC tolerated cryopreservation and proliferated either as spheroids or adherent cells, and developed xenografts in immunodeficient mice, ensuring robust utility as a cell line. Intriguingly, the resected tumor focally contained serous carcinoma (SC) in a tiny protruding lesion. Both organoids and derivative xenografts resembled the CCC component of the original tumor in histology, immunostaining profile, and genome‐wide copy number changes, including focal gain of MET. Genomic analysis revealed that both organoids and the CCC component harbored only a few mutations, of which 2 mutations were shared in common. In contrast, the SC component showed a mutator‐phenotype and prominent genome instability along with biallelic inactivation of TP53, but none of them were found in organoids or the CCC component. The PDC proved sensitive to major chemotherapeutic agents and MET inhibitors. These observations clearly indicated that the PDC, designated as YMC7, can be used as a novel cCCC cell line and provide novel insights into the pathogenesis of mixed cervical adenocarcinoma. As a valuable resource for rare cancer, it will likely contribute to investigations in many fields.

Horizons of nanotechnology applications in female specific cancers

Female-specific cancers are the most common cancers in women worldwide. Early detection methods remain unavailable for most of these cancers, signifying that most of them are diagnosed at later stages. Furthermore, current treatment options for most female-specific cancers are surgery, radiation and chemotherapy. Although important milestones in molecularly targeted approaches have been achieved lately, current therapeutic strategies for female-specific cancers remain limited, ineffective and plagued by the emergence of chemoresistance, which aggravates prognosis. Recently, the application of nanotechnology to the medical field has allowed the development of novel nano-based approaches for the management and treatment of cancers, including female-specific cancers. These approaches promise to improve patient survival rates by reducing side effects, enabling selective delivery of drugs to tumor tissues and enhancing the uptake of therapeutic compounds, thus increasing anti-tumor activity. In this review, we focus on the application of nano-based technologies to the design of novel and innovative diagnostic and therapeutic strategies in the context of female-specific cancers, highlighting their potential uses and limitations.

Mucosal human papillomavirus detection and TP53 immunohistochemical expression in non-melanoma skin cancer in Tunisian patients

BACKGROUND

Several studies have reported the oncogenic role of human papillomavirus (HPV) in non-melanoma skin cancer (NMSC) carcinogenesis. Considering that HPV could affect tumor protein 53 (TP53) degradation via E6 oncoprotein, we evaluated the expression of TP53 according to HPV infection and E6 expression.

METHODS

Biopsy specimens from 79 NMSCs (28 squamous cell carcinomas, 21 keratoacanthomas and 30 basal cell carcinomas) were enrolled. Nested PCR was used to detect mucosal HPV (mHPV) DNA. Genotyping was performed by reverse line hybridization. Expression of TP53 and E6 was evaluated by immunohistochemistry.

RESULTS

mHPVs were detected in 34.2% (27/79) of NMSC, with 92.6% (25/27) of high-risk HPV (HR-HPV) types. HPV16-E6-positive expression was observed in all HPV16-positive samples. TP53 high expression was found in 51.4% (37/72) of specimens. In this group, 78.4% were HPV-negative (P = 0.014). TP53 expression was negative in 8/10 of HPV E6-positive specimens. Multivariate analysis showed that TP53 was associated with HPV infection independently of histopathologic type (P = 0.005).

CONCLUSION

This study showed a high prevalence of mHPV in NMSC. Active infections assessed by E6 expression are associated with loss of p53 function, highlighting the involvement of mHPV in NMSC carcinogenesis.

ТР53 Codon 72 Polymorphism and Human Papilloma Virus-Associated Cervical Cancer in Kyrgyz Women

Background: The aim of this study was to ascertain the magnitude of association of gene ТР53 Arg72Pro polymorphic marker with cervical cancer (CC) in Kyrgyz women. Methods: We identified and included 205 women of Kyrgyz ethnicity for this case-control study, of whom N=103 were women (mean age 53.5 ± 10.0 years) with histologically confirmed CC and N=102 controls (mean age 46.5 ± 8.5 years). We detected human papilloma virus (HPV) DNA types 16 and 18 using polymerase chain reaction (PCR) with hybridization/fluorescent detection. Genotypes of ТР53 gene Arg72Pro polymorphism were identified using PCR-RFLP assay. Results: Eighty-eight percent (90/103) women with CC had HPV, of whom 43.4% (39/90) had HPV type 16, 24.4% (22/90) had HPV type 18, whereas 32.2% (29/90) carried both types. The univariate analysis of allele and genotype distribution of Arg72Pro polymorphic marker of ТР53 gene showed no difference between CC and control groups (χ2=1.24, р=0.54). However, when CC cases associated with HPV were tested against controls, Arg72 allele and Arg72Arg genotype prevalence were greater compared to controls (χ²=7.25; р=0.027 for genotypes and χ²=6.83; р=0.009 for alleles). In HPV-positive women, Arg72Arg genotype of ТР53 gene was associated with a 1.85-fold increase in the likelihood of CC (OR=1.85 [95% confidence interval (CI) 1.03-3.32]), whereas Arg72 allele increased this likelihood 1.94-fold (OR=1.94 [95% CI 1.20-3.15]). Conclusions: Arg72Arg genotype and Arg72 allele of ТР53 gene in Kyrgyz women increase the risk of HPV-associated CC.

A novel human in vitro papillomavirus type 16 positive tonsil cancer cell line with high sensitivity to radiation and cisplatin

Background

Human papillomavirus (HPV) is an established risk factor for oropharyngeal squamous cell carcinoma (OSCC). The aim was to establish cell lines from HPV-positive tonsil carcinomas to be used for treatment development.

Methods

Fresh samples from 23 HPV-positive tonsil carcinomas were cultivated in vitro. The established cell line was analyzed for viral characteristics, cell karyotype, TP53 status, and growth capabilities in nude mice. In vitro studies of sensitivities to radiation, cisplatin and cetuximab were performed.

Results

After 19 months (eight passages), one cell line, LU-HNSCC-26, was established in vitro and also grew as xenografts. The tumor was from a 48 year old non-smoking man with non-keratinizing, p16 positive tonsil OSCC, stage T2N0M0 with HPV16. It contained 19.5 (CV% 3.7) HPV16 copies/cell (passage 8). The complete HPV16 genome sequence was obtained. Episomal HPV16 was present with an E2/E7 ratio of 1.1 (CV% 2.6). In addition, HPV16 mRNA specific for the intact E2 gene was detected. The viral expression manifested 1.0 (CV% 0.1) E7 mRNA copies per HPV16 genome. The karyotype was determined and the cell line demonstrated wild type TP53. The ID50 for radiation was 0.90 Gy and the IC50 for cisplatin was 0.99 μmol/L. The cell line was inhibited to a maximum of 18% by cetuximab.

Conclusions

We established an in vitro tonsil carcinoma cell line containing episomal HPV16. This is an important step towards efficient treatment development.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5469-8) contains supplementary material, which is available to authorized users.

Genetic Susceptibility for Cervical Cancer in African Populations: What Are the Host Genetic Drivers?

Human papillomavirus (HPV) is an essential but not a sufficient cervical cancer etiological factor. Cancer promoters, such as host genetic mutations, significantly modulate therapeutic responses and susceptibility. In cervical cancer, of interest have been viral clearing genes and HPV oncoprotein targets, for which conflicting data have been reported among different populations. This expert analysis evaluates cervical cancer genetic susceptibility biomarkers studied in African populations. Notably, the past decade has seen Africa as a hotbed of biomarker and precision medicine innovations, thus potentially informing worldwide biomarker development strategies. We conducted a critical literature search in PubMed/MEDLINE, Google Scholar, and Scopus databases for case-control studies reporting on cervical cancer genetic polymorphisms among Africans. We found that seven African countries conducted cervical cancer molecular epidemiology studies in one of Casp8, p53, CCR2, FASL, HLA, IL10, TGF-beta, and TNF-alpha genes. This analysis reveals a remarkable gap in cervical cancer molecular epidemiology among Africans, whereas cervical cancer continues to disproportionately have an impact on African populations. Genome-wide association, whole exome- and whole-genome sequencing studies confirmed the contribution of candidate genes in cervical cancer. With such advances and omics technologies, the role of genetic susceptibility biomarkers can be exploited to develop novel interventions to improve current screening, diagnostic and prognostic methods worldwide. Exploring these genetic variations is crucial because African populations are genetically diverse and some variants or their combined effects are yet to be discovered and translated into tangible clinical applications. Thus, translational medicine and flourishing system sciences in Africa warrant further emphasis in the coming decade.

Tongue carcinoma in young adults: a review of the literature

SUMMARY

A recent reduction in the number of smoke-related tumours has been observed thanks to the diffusion of anti-tobacco campaigns carried out in the majority of developed countries. Nevertheless, as demonstrated by recent global epidemiologic studies, squamous cell carcinoma of the mobile tongue appears to be progressively increasing in incidence, particularly among young adults and especially in females. The driving mechanism responsible for such changes is still to be precisely defined. Several genetic studies have compared the mutational pattern of tongue squamous cell carcinoma in young adults to that of more elderly patients, without identifying significant differences that may help in better characterising this subgroup of subjects. Tongue squamous cell carcinomas in young adults have been historically considered as particularly aggressive clinical entities, with a high risk of loco-regional relapse, survival rates inferior to those of the general head and neck cancer group and need for a more aggressive therapy. However, considering the most recent studies, prognostic results in this patient group are heterogeneous and it is not possible to confirm this tendency. Thus, it is not justified to embrace different therapeutic approaches according to patient age. Eventually, an additional element to consider when examining young subjects affected by tongue cancer is the possibility of genetic predisposition. Alterations affecting pathways involved in DNA repair, surveillance of genetic stability or regulation of cellular growth may determine an increased likelihood of developing head and neck cancers.

Nucleotide variants and protein expression of TP53 in a Sri Lankan cohort of patients with head and neck cancer

Head and neck cancer (HNC) is the leading cancer in Sri Lankan males and second most common cancer among Sri Lankan females. This is the first study, to the best of our knowledge, that has focused on investigating the association between TP53 somatic DNA variants, with p53 protein expression and risk factors in a cohort of Sri Lankan patients with HNC. A total of 44 patients with cancer and 20 healthy controls were studied. In total, 36 genomic DNA sequence variants were found, including several novel variants (two deletions in exons 4 and 6, two in the 3′ untranslated region and several intronic variants). A total of 14 tumour samples carried pathogenic TP53 mutations. A random selection of 24 samples was analysed immunohistochemically for p53 protein expression. All the samples with point missense variants were strongly immuno-positive, whereas, samples with nonsense and frameshift TP53 variants were immuno-negative for p53 immunohistochemical staining. Although, the human papilloma virus is a known risk factor for HNC, results from the present study identified an absence or lower level of infection in the Sri Lankan cohort.

Oncogenicitiy Comparison of Human Papillomavirus Type 52 E6 Variants

Human papillomavirus (HPV) infection contributes to virtually all cases of cervical cancer, the fourth most common cancer affecting women worldwide. The oncogenicity of HPV is mainly attributable to the E6 and E7 oncoproteins. HPV-52 is the seventh most common HPV type globally, but it has a remarkably high prevalence in East Asia. In previous studies it has been speculated that the oncogenicity might vary among different HPV-52 variants. In the present study, we compared the oncogenicity of E6 derived from the HPV-52 prototype and three commonly found variants, V1 (K93R), V2 (E14D/V92L) and V3 (K93R/N122K), through molecular and phenotypic approaches. We demonstrated that cells containing V1 achieved higher colony formation and showed greater cell migration ability when compared to other variants, but no difference in cell immortalization ability was observed. At the molecular level, the three variants formed complexes with E6-associated protein (E6AP) and p53 as efficiently as the prototype. They degraded p53 and PSD95/Dlg/ZO-1(PDZ) proteins, including MAGI-1c and Dlg, to a similar extent. They also exhibited a similar subcellular localization, and shared a half-life of approximately 45 min. Our findings provide a clearer picture of HPV-52 E6 variant oncogenicity, which is important for further studies aiming to understand the unusually high prevalence of HPV-52 among cervical cancers in East Asia.

Ubiquinol-cytochrome C reductase core protein II promotes tumorigenesis by facilitating p53 degradation

Background

Ubiquinol-cytochrome C reductase core protein II (QCR2) is essential for mitochondrial functions, yet, its role in cancer development has remained elusive.

Methods

The expression of QCR2 in cancer patients was assessed by immunohistochemistry. The proliferation of cancer cells was assessed by CCK-8 assay, EdU staining and Flow cytometry analysis. The biological function of QCR2 and PHB were determined using western blotting, RT-qPCR, microarray analysis and xenografts. The interactions between proteins and the ubiquitination of p53 were assessed by immunoprecipitation, mass spectrometry analysis and GST pull down. The subcellular location of PHB and QCR2 was assessed by immunoblotting and immunofluorescence.

Finding

The expression of QCR2 is upregulated in multiple human tumors. Suppression of QCR2 inhibits cancer cell growth by activating p53 signaling and inducing p21-dependent cell cycle arrest and senescence. QCR2 directly interacts with PHB in the mitochondria. Overexpression of QCR2 inhibits PHB binding to p53 in the nucleus, and facilitates p53 ubiquitination and degradation, consequently leading to tumorigenesis. Also, increased QCR2 and decreased PHB protein levels are well correlated with decreased expression of p21 in cervical cancer tissues.

Interpretation

These results identify a novel role for QCR2, together with PHB, in negative regulation of p53 stability and activity, thus promote cervical carcinogenesis.

Fund

“973” Program of China, the National Science-technology Supporting Plan Projects, the National Natural Science Foundation of China, National Science and Technology Major Sub-Project and Technical Innovation Special Project of Hubei Province.

Interaction between TP53 and XRCC1 increases susceptibility to cervical cancer development: a case control study

BACKGROUND

Cervical cancer is the 4th highest cause of female reproductive tract malignancies. Multiple loci have been identified as important determinant factors for tumor susceptibility. In this report, we aimed to explore the roles of gene polymorphisms affecting x-ray repair cross complementing 1 (XRCC1), the tumor protein p53 (TP53), and fibroblast growth factor receptor 3 (FGFR3) in the context of susceptibility to cervical cancer. Additionally, we assessed the impact of single nucleotide polymorphism-single nucleotide polymorphism (SNP-SNP) interaction of these three genes in the context of cervical cancer risk in Chinese women.

METHODS

A case-control study consisted of 340 women located in Chongqing. Of these women, 121 were diagnosed with cervical cancer, 118 served as healthy controls, and 101 were specifically recruited elderly patients above the age of 80 who showed no history of cervical cancer. Three SNPs (XRCC1 rs25487, TP53 rs1042522, and FGFR3 rs121913483) were examined using mutation analysis of mismatch amplification PCR (MAMA-PCR) on samples obtained from peripheral blood.

RESULTS

Our results indicated that females from southwestern China all exhibited a wild-type phenotype at FGFR3 rs121913483. We also observed that the rs25487 mutation was significantly increased within the cervical cancer population. A 2-locus SNP-SNP interaction pattern (rs25487 and rs1042522) was significantly associated with cervical cancer risk (cases vs. negative controls: OR = 4.63, 95% CI = 1.83-11.75; cases vs. elderly group: OR = 17.61, 95% CI = 4.34-71.50).

CONCLUSIONS

This is the first study to identify a novel interaction between the XRCC1 and TP53 genes that is highly associated with susceptibility to cervical cancer risk in a female population in southwestern China.

P53 Codon 72 Polymorphism and Risk for Squamous Cell Carcinoma of the Penis: A Caucasian Case-Control Study

Squamous cell carcinoma of the penis is a rare but often aggressive disease. A large proportion of penile cancers are associated with HPV infection, mainly with HPV high-risk subtypes 16 and 18. From other HPV-related malignancies a link between a functional SNP in the p53 gene (rs1042522, p.Arg72Pro) and a higher disease risk in the presence of HPV is documented. The p53 p.Arg72 variant was described as a risk factor for developing a malignancy in combination with the presence of HPV as the p.72Arg variant is more prone to HPV E6 protein-mediated degradation than the p.72Pro variant. For penile carcinoma there are only sparse data available on this topic. We therefore analyzed the distribution of this p53 codon 72 SNP in a cohort of 107 penile cancer patients and a healthy control group (n=194) using Restriction Fragment Length Polymorphism (RFLP) analysis. After DNA isolation a PCR amplicon including the variant nucleotide was generated. Based on the variant nucleotide this amplicon can be cleaved into two parts or remain unaffected by a restriction enzyme. Subsequent electrophoresis allowed the discrimination of SNP alleles in the investigated sample. Comparison of the allelic variants revealed no significant differences in the distribution of this SNP between cases and controls (p=0,622). There was also no difference in SNP distribution between cases with/without HPV infection (p=0,558) or histologic variants (p=0.339). In order to strengthen the impact of our data we performed a combined analysis of all published data on this topic with our results. This ended up in SNP distribution data from 177 cases and 1149 controls. Overall, there were also no significant differences in the allelic distribution of the p53 codon 72 SNP between either cases and controls (p=0,914) or HPV-positive and HPV-negative cases (p=0,486). From this most comprehensive data available to date we conclude that there is no influence of the p53 codon 72 SNP on the risk of development of penile carcinoma in Caucasians even in the presence of HPV.