The prevalence of human papillomavirus in colorectal adenomas and adenocarcinomas: a systematic review and meta-analysis

Different Metabolic Associations of Hepatitis C With Colon and Rectal Cancers: A 9-Year Nationwide Population-Based Cohort Study

BACKGROUND

Whether HCV infection is associated with colorectal cancer (CRC) development remains inconclusive.

METHODS

A nationwide population-based cohort study of the Taiwan National Health Insurance Research Database was conducted.

RESULTS

From 2003 to 2012, 1:2:2 propensity score-matched HCV-treated [interferon-based therapy ≥ 6 months, surveys for CRC (n = 9017), colon cancer (CC) (n = 9,022) and rectal cancer (RC) (n = 9,033), HCV-untreated and HCV-uninfected cohorts CRC (n = 18034), CC (n = 18,044) and RC (n = 18,066) were enrolled. The HCV-uninfected cohort had the lowest cumulative incidence of CRC (0.117%; 95% CI: 0.062%-0.207%), whereas the HCV-treated (0.966%; 0.375-2.122%) and HCV-untreated (0.807%; 0.485%-1.280%) cohorts had similar incidences (P = .0662); HCV infection [reference: HCV-untreated cohort, HCV-treated: hazard ratio (HR): 0.598; 95% CI HR: 0.337-1.059; HCV-uninfected: 0.250; 0.138-0.456] and age ≥ 49 years (3.128;1.751-5.59) were associated with CRC development. The HCV-untreated cohort had the highest cumulative incidence of CC (0.883%; 0.371-1.839%), while HCV-treated (0.478%; 0.110-1.518%) and HCV-uninfected cohorts (0.147%; 0.071-0.284%) had similar incidences (P = .4853); HCV infection (HCV-treated: 0.474; 0.232-0.971; HCV-uninfected: 0.338; 0.184-0.62), male sex (2.18; 1.301-3.654), age≥ 49 years (4.818; 2.123-10.936) and diabetes (1.983; 1.205-3.262) were associated with CC development. A higher RC cumulative incidence was noted in the HCV-untreated cohort (0.332%; 0.151-0.664%) than in the HCV-uninfected cohort (0.116%; 0.054-0.232%) (P = .0352); HCV infection (HCV-treated: 0.691; 0.295-1.617; HCV-uninfected: 0.424; 0.207-0.867), age ≥ 49 years (3.745, 1.576-8.898) and stroke (3.162; 1.366-7.322) were associated with RC development.

CONCLUSIONS

The baseline associations were HCV infection and age ≥ 49 years with CRC; male sex and diabetes with CC; and stroke with RC. Anti-HCV therapy might reverse the risk of HCV-related CC but not RC.

Mendelian randomization analyses support causal relationships between HPV infection and colorectal cancer

BACKGROUND

Human Papillomavirus (HPV) infections leading to a variety of diseases are a global public health issue.Despite the well-established link between HPV infection and cervical and anogenital cancers, there is ongoing debate regarding the relationship between HPV infection and colorectal cancer (CRC).

METHODS

We evaluated the causal connection between HPV infection and CRC utilizing five Mendelian randomization (MR) methods. Genome-wide association studies (GWAS) datasets for HPV were obtained from the IEU Open GWAS project. A large summary of colorectal adenocarcinoma and colorectal cancer data from the FinnGen database was used as the outcome.

RESULTS

Our analysis revealed a significant association between genetically predicted HPV-16 infection and the risk of paternal colorectal adenocarcinoma (HPV-16: OR 1.058, 95% CI 1.013-1.102; p = 0.011), as well as CRC (HPV-16: OR 1.045, 95% CI 1.005-1.085; p = 0.025).

CONCLUSION

These findings provide compelling evidence for a causal effect of HPV infection on the development of CRC. Further investigations into the underlying mechanisms and elucidation of this association are necessary to identify viable interventions for the prevention and treatment of HPV-associated CRC.

Association of G12D mutation in the KRAS gene with HPV and EBV in gastrointestinal cancer tissues

OBJECTIVE

This study aimed to explore the potential relationship between viral infections and gastrointestinal (GI) malignancies, focusing on the presence of KRAS G12D mutations. Specifically, we investigated the association of viral agents, including human papillomavirus (HPV) and Epstein-Barr virus (EBV), with KRAS G12D mutations in GI cancers to better understand their combined role in cancer development.

METHODS

This cross-sectional study comprised 92 patients diagnosed with GI cancer and 100 healthy individuals in the control group. All samples were examined to detect the KRAS G12D gene mutation and the existence of HPV and EBV using real-time polymerase chain reaction assays.

RESULTS

HPV and EBV DNA were detected in 5.4% and 51.4% of gastric cancer samples and in 7.3% and 49.1% of colorectal cancer samples, respectively. Analysis of KRAS G12D in plasma samples revealed heterozygous mutations in 54% of patients with gastric cancer and 35% of patients with colorectal tumors. Among EBV-positive colorectal cancer samples, 1.8% were wild-type, while 47.2% exhibited heterozygous mutations. Among HPV-positive colorectal cancer patients, 1.8% exhibited wild-type KRAS, 5.4% had heterozygous mutations, and 3.2% had homozygous mutations.

CONCLUSION

This study detected a significant correlation between the presence of viral agents and KRAS G12D mutations.

Epstein-Barr Virus and Human Papillomavirus Coinfection in Colorectal Carcinoma: Systematic Review and Meta-Analysis of the Prevalence

Colorectal cancer (CRC) is one of the most common types of cancer worldwide. In addition to known risk factors, oncoviruses have attracted exceptional attention from recent research. Numerous hypotheses on interactions between the Epstein-Barr virus (EBV) and Human papillomavirus (HPV) in CRC are still based on sparse prevalence data of these coinfections. The aim of this study was to perform a comprehensive literature search regarding EBV/HPV coinfection in patients with CRC and to provide its prevalence in the target population. Three electronic databases (PubMed, SCOPUS, and WoS) were searched, and after a double reviewer check, six publications were included in the qualitative and quantitative analyses. This systematic review showed the limited number of studies dealing with the prevalence and role of EBV/HPV coinfection in CRC and the heterogeneity of methodology and reported results. However, in a total of 635 patients, it also showed that the identified 15% EBV/HPV prevalence in CRC (15%, 95% CI: 7-23%) could suggest that further investigations are needed. Histopathologically, all coinfected CRCs were adenocarcinomas, from intermediate to intermediate and high grade, reported across four studies. Increased knowledge about the infectious origin of various cancers, including CRC, has the potential to enhance the vigilance of scientists to design future large-scale multicenter prospective studies.

Colorectal Cancer: Epidemiology, Risk Factors, and Prevention

Colorectal cancer (CRC) is the third most common cancer and the second most common cause of cancer mortality worldwide. There are disparities in the epidemiology of CRC across different populations, most probably due to differences in exposure to lifestyle and environmental factors related to CRC. Prevention is the most effective method for controlling CRC. Primary prevention includes determining and avoiding modifiable risk factors (e.g., alcohol consumption, smoking, and dietary factors) as well as increasing protective factors (e.g., physical activity, aspirin). Further studies, especially randomized, controlled trials, are needed to clarify the association between CRC incidence and exposure to different risk factors or protective factors. Detection and removal of precancerous colorectal lesions is also an effective strategy for controlling CRC. Multiple factors, both at the individual and community levels (e.g., patient preferences, availability of screening modalities, costs, benefits, and adverse events), should be taken into account in designing and implementing CRC screening programs. Health policymakers should consider the best decision in identifying the starting age and selection of the most effective screening strategies for the target population. This review aims to present updated evidence on the epidemiology, risk factors, and prevention of CRC.

Multiethnic Trends in Early Onset Colorectal Cancer

Current characteristics of early onset colorectal cancer (EOCRC) in the United States have been mainly studied in Whites, African Americans, and Hispanics, but little is known in regard to EOCRC in Asians and Native Hawaiians in the US. EOCRC was examined in Hawaii's multiethnic population. Data from the Hawaii Tumor Registry was used to analyze colorectal cancer (CRC) cases diagnosed in Hawaii from 2000-2019 by subsite, age, gender, ethnicity, and stage. Ethnicity analyses were limited to 3524 CRC cases, diagnosed between 2015-2019. Average annual 5-year age-adjusted incidence and mortality rates, average annual percent change over time, and 5-year survival were evaluated. Group comparisons utilized Chi-square and binomial proportion tests. Overall CRC incidence and mortality declined and were more pronounced for colon than rectal/rectosigmoid junction cancers. Colon cancer incidence rates significantly increased 1.46-fold for cases diagnosed under 45 years of age and rectal/rectosigmoid cancers significantly increased 1.54-fold for cases 45-54 years of age. CRC incidence increased sharply for females aged 45-54 years from 2000-2009 to 2010-2019, and increases in colon and rectal/rectosigmoid cancer among individuals aged 45-54 were higher for females. Among both sexes, the increase in rectal/rectosigmoid cancer incidence for individuals under 55 years was highest for stage I cancers. Overall, the mean (SD) age of CRC diagnosis was 5-10 years earlier for Native Hawaiians (60.6 [13.3] years) compared with Japanese, Chinese, Filipinos, Whites, and Other Asians (p < 0.001). Native Hawaiians constituted a greater proportion of CRC diagnosed under age 55 years and, conversely, a smaller proportion of cases 55 years and older compared with Japanese, Chinese, Filipinos, Whites, and Other Asians. Native Hawaiians had a significantly higher CRC-related mortality rate (14.5 per 100,000 [95% CI: 12.4, 16.8]) compared with Japanese (10.7 per 100,000 [95% CI: 9.3, 12.3]) and a significantly lower CRC survival rate (62.2% [95% CI: 59.1, 65.2]) compared with Japanese (71.9% [95% CI: 69.9, 73.8]), Filipinos (71.9% [95% CI: 69.2, 74.4]), Chinese (70.2% [95% CI: 65.5, 74.4]), Whites (69.3% [95% CI: 67.1, 71.4]), and Other Asians (71.7% [95% CI: 66.2, 76.5]). In our diverse US population, Native Hawaiians contribute disproportionately to EOCRC and present 5-10 years earlier than Whites, Japanese, Chinese, and Filipinos. EOCRCs are increasing faster in females than males in Hawaii, which differs from trends in the general US population. Emerging ethnic disparities in EOCRC in the US speak to the need for studies on targeted interventions and ethnic-specific risk factors for EOCRC.

Colorectal cancer and gut viruses: a visualized analysis based on CiteSpace knowledge graph

Background

Gut microbiome is a complex community of microbes present in the human gut and plays an important role in the occurrence and progression of colorectal cancer (CRC). However, the relationship between virus and CRC has not been fully understood.

Objective

To explore the hot spots and research trends in the field of CRC and virus.

Methods

By using the bibliometric analysis tool CiteSpace and based on the articles of the Web of Science Core Collection (WoSCC) database, the country, institution, highly cited literature, keywords and so on were visually analyzed.

Results

A total of 356 research articles on CRC from 2001 to 2023 were thoroughly analyzed. The USA and China have made the largest contribution in the field of virus and CRC. The Helmholtz Association published the most papers. There were relatively few cooperations among institutions from different countries. The results of keyword cluster analysis proved that the literature on the relationship between human cytomegalovirus (CMV) and CRC was the most widely studied aspect in this field. "Gut microbiota," "inflammatory bowel disease," "hepatitis b virus," and "human papillomavirus infection" are the current research hotspots; "oncolytic virus," "apoptosis," and "gut microbiome" are the recent research frontiers and should be paid closer attention.

Conclusion

By using CiteSpace bibliometric software, the visual analysis reflected the research trends and hot topics of virus and CRC. In addition, the prevalence and mechanism of specific virus on CRC were also reviewed, which provides valuable references for future CRC research.

Prevalence and genotype distribution of human papillomavirus in cervical adenocarcinoma (usual type and variants): A systematic review and meta-analysis

Cervical glandular neoplasms represent a heterogeneous group of tumors for which a comprehensive overview of the involvement of high-risk human papillomaviruses (HPV) in pathogenesis is still lacking. We first searched MEDLINE (PubMed), Embase, and Scopus databases (until October 2022), and systematically reviewed available literature. We then quantitatively estimated both pooled and genotype-specific prevalence of HPV DNA as well as the influence of various factors (e.g., geographical region, histological subtype, tissue/sample type) on computed effect size by means of random effects meta-analysis. In total, 379 studies comprising 17 129 cases of cervical adenocarcinoma were identified. The pooled HPV prevalence was 78.4% (95% confidence interval [95% CI]: 76.2-80.3) with a significant between-study heterogeneity (I2  = 79.4%, Q test p < 0.0001). Subgroup analyses indicated that the effect size differed substantially by geographical region (from 72.5% [95% CI: 68.7-76.1] in Asia to 86.8% [95% CI: 82.2-90.3] in Oceania) (p < 0.0001) and histological subtype of cancer (from 9.8% [95% CI: 5.5-17] in gastric-type to 85% [95% CI: 79.6-89.2] in usual-type cervical adenocarcinoma) (p < 0.0001). HPV16 and HPV18 were by far the most frequently detected viral strains with specific prevalence of 49.8% (95% CI: 46.9-52.6) and 45.3% (95% CI: 42.8-47.8), respectively. When stratified by continent or histologic variant, these genotype-specific results varied in a relatively limited manner. Altogether, these findings support that all histological subtypes of cervical adenocarcinoma are etiologically linked to high-risk HPV but to varying degrees. Therefore, a dual-criteria classification taking into account accurately both morphological and virological aspects could be an interesting evolution of the current binary World Health Organization classification, better reflecting the pathogenic diversity of the disease.

Human Papilloma Virus: An Unraveled Enigma of Universal Burden of Malignancies

HPV, or Human Papilloma Virus, has been the primary causative agent of genital warts and cervical cancer worldwide. It is a sexually transmitted infection mainly affecting women of reproductive age group, also infecting men and high-risk group individuals globally, resulting in high mortality. In recent years, HPV has also been found to be the major culprit behind anogenital cancers in both gender and oropharyngeal and colorectal cancers. Few studies have reported the incidence of HPV in breast cancers as well. For a few decades, the burden of HPV-associated malignancies has been increasing at an alarming rate due to a lack of adequate awareness, famine vaccine coverage and hesitancy. The effectiveness of currently available vaccines has been limited to prophylactic efficacy and does not prevent malignancies associated with post-exposure persistent infection. This review focuses on the current burden of HPV-associated malignancies, their causes and strategies to combat the growing prevalence of the cancers. With the advent of new technologies associated with treatment pertaining to therapeutic interventions and employing effective vaccine coverage, the burden of this disease may be reduced in the population.

Experience of a District General Hospital With a Diverse Community in Operated Colorectal Cancers According to Ethnic Background

Background

This study aimed to investigate disparities in colorectal cancer (CRC) patients’ demographics according to the five major ethnicities of patients living in the catchment area of North Middlesex Hospital.

Methodology

This retrospective study included CRC patients operated on between January 1, 2010, and December 31, 2014. Records dating to the end of the five-year follow-up were extracted anonymously from a database of CRC outcomes at the North Middlesex University Hospital NHS Trust. Comparisons were made according to ethnicity, patient demographics, type of presentation, cancer location, stage at diagnosis, recurrence, and mortality.

Results

A total of 176 adult patients were operated on for CRC between January 1, 2010, and December 31, 2014. The majority of the patients were referred as two-week wait target referrals. Emergency presentation of CRC was the highest in White non-UK patients. The White British Irish patients had their tumors mostly in the cecum, followed by the sigmoid colon, while the rectum followed by the sigmoid colon were the most common sites in the Black population. All study populations mainly presented with stage I disease, and the next highest incidence of cancers according to stage and ethnicity was stage IIIb in the Black population.

Conclusions

Differences in the ethnic background are important factors, especially in a diverse community, which can impact the age and mode of presentation of the disease, as well as the stage it starts to present. The location of the primary tumor, metastases, and recurrence sites are all affected by the ethnic background, which, subsequently, affect the survival of the patient.

The complexity of human papilloma virus in cancers: a narrative review

Among human tumorigenic viruses, the role of Human papillomavirus (HPV) has been proven as one of the most important oncoviruses that are associated with a large number of cancers. Most cancers of the genital area such cervical and anal cancer as are caused by HPV, and in many other cancers, such as colorectal, gastric, liver, esophageal, urinary bladder, and head and neck cancers, it is considered as one of the important risk factors. Our search was conducted for published researches between 2000 and 2022 by using several international databases including Scopus, PubMed, and Web of Science as well as Google scholar. We also evaluated additional evidence from relevant published articles. It has been demonstrated that HPV can promote tumorigenesis via focusing on genes, proteins, and signaling pathways, by using E6 and E7 oncoproteins and inhibiting two crucial tumor suppressors, P53 and Rb. The following study was performed to investigate different malignant cancers under the influence of HPV infection and changes in molecular factors caused by HPV infection.

Host Genetics and Microbiota Interactions in Colorectal Cancer: Shared or Independent Risk?

The role of microbiota in colorectal cancer has been studied since alterations in its composition were observed. In addition, there are more and more pieces of evidence that microbiota could be implicated in colorectal cancer progression. Thus, the components of the microbiota could be biomarkers for the diagnosis and prognosis of colorectal cancer. In addition, it is important to address how the microbiota interacts with the host and how the host shapes the microbiota, in order to understand the biological pathways and mechanisms involved in their relationship and the consequences of their interactions in colorectal cancer. Thereby, it could be possible to find feasible measures and treatments to prevent or better diagnose colorectal cancer. In this review, we will try to summarize the role of the microbiota in colorectal cancer and its interactions with the host and the host genetics, coming to some conclusions that could be useful to find the gaps in our knowledge and propose future steps in this field.

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.

Human Papillomavirus and Risk of Colorectal Cancer: An Analysis of Nationwide Claims Data

Background and Objectives: Although human papillomavirus (HPV) is a major etiology of cervical and anogenital cancers, whether it is associated with colorectal carcinogenesis is yet undetermined. Materials and Methods: The longitudinal association of HPV infection with colorectal cancer (CRC) was evaluated using 2000-2013 data from a nationwide Taiwanese claims database. In this retrospective cohort study, 358 patients with primary HPV diagnoses (HPV-infected cohort) and 1432 patients without such a diagnosis (HPV-uninfected cohort) were recruited between 2000 and 2006. Both cohorts were followed up to identify CRC incidences from 2006 to 2013. Hazard ratios (HRs) and their 95% confidence intervals (CIs) derived from Cox proportional hazards models were used to estimate the association between HPV and CRC risk. Results: The HPV-infected cohort had a significantly higher cumulative incidence of CRC than the HPV-uninfected cohort. The presence of HPV was associated with an increased risk of CRC (adjusted HR, 1.63; 95% CI, 1.02-3.62). Furthermore, the significant HPV-CRC risk association was evident in both sexes. Conclusions: This population-based cohort study reveals longitudinal evidence that HPV is associated with an increased risk of CRC. Further studies are required to verify the role of HPV in colorectal carcinogenesis.

Viral Infection in Esophageal, Gastric, and Colorectal Cancer

The human gastrointestinal tract, which constitutes the digestive system, contains a large number of virus particles that maintain organizational homeostasis and health. Conversely, viral pathogens have also attracted attention for their involvement in the pathogenesis of certain cancers, including gastrointestinal cancers. To aid prevention and treatment of these cancers, the relevance of gastrointestinal viral factors as potential risk factors needs to be carefully investigated. This review summarizes and discusses the available literature on the relationship between the development of esophageal, gastric, and colorectal cancers and their corresponding viruses. This review reveals that research on the association between colorectal cancer and viruses, in particular, is still in its infancy compared to the association between HPV and esophageal cancer and between EBV and gastric cancer.

Cervical and endometrial cancers of intestinal origin diagnosed 18 years after vaginal replacement with a sigmoid colon segment: a case report and review of the literature

Background

Sigmoid colpoplasty is a surgical method for the treatment of vagina agenesis. Malignant tumors of neovaginas derived from sigmoid colons are rare.

Case presentation

We report a 33-year-old woman who underwent sigmoid colpoplasty for vaginal agenesis and presented 18 years later with vaginal bleeding. Examination revealed cancer of the neovagina with involvement of the cervix and endometrium. The patient was administered four cycles of chemotherapy because she refused surgery.

Conclusions

Patients with a history of colpoplasty should undergo long-term comprehensive testing after reconstruction, including regular gynecological, colposcopic, and gastrointestinal examinations. In patients with cancer of the neovagina, a comprehensive treatment plan should be developed in consultation with gynecologists and surgeons. There is no standard treatment, although surgery plus chemotherapy or radiotherapy appears to be effective.

The Involvement of Human Papilloma Virus in Gastrointestinal Cancers

Human Papilloma Virus (HPV) is one of the most common sexually transmitted infections worldwide. HPV infection has a strong relationship with the onset of cervix uteri, vagina, penis, anus, and oropharynx, but also tonsils and tongue cancers. Some epidemiological data indicate that except for gynecologic cancers, HPV infection can be one of the risk factors associated with a greater risk of induction and progression of gastrointestinal cancers. Data, however, remain contradictory and definite conclusions cannot be drawn, so far. The following review aims to organize recent evidence and summarize the current state of knowledge regarding the association between HPV infection and gastrointestinal tumors primarily focusing on esophageal, liver, gastric, colorectal, and anal cancers.

Metagenomic analysis of primary colorectal carcinomas and their metastases identifies potential microbial risk factors

The paucity of microbiome studies at intestinal tissues has contributed to a yet limited understanding of potential viral and bacterial cofactors of colorectal cancer (CRC) carcinogenesis or progression. We analysed whole-genome sequences of CRC primary tumours, their corresponding metastases and matched normal tissue for sequences of viral, phage and bacterial species. Bacteriome analysis showed Fusobacterium nucleatum, Streptococcus sanguinis, F. Hwasookii, Anaerococcus mediterraneensis and further species enriched in primary CRCs. The primary CRC of one patient was enriched for F. alocis, S. anginosus, Parvimonas micra and Gemella sp. 948. Enrichment of Escherichia coli strains IAI1, SE11, K-12 and M8 was observed in metastases together with coliphages enterobacteria phage φ80 and Escherichia phage VT2φ_272. Virome analysis showed that phages were the most preponderant viral species (46%), the main families being Myoviridae, Siphoviridae and Podoviridae. Primary CRCs were enriched for bacteriophages, showing five phages (Enterobacteria, Bacillus, Proteus, Streptococcus phages) together with their pathogenic hosts in contrast to normal tissues. The most frequently detected, and Blast-confirmed, viruses included human endogenous retrovirus K113, human herpesviruses 7 and 6B, Megavirus chilensis, cytomegalovirus (CMV) and Epstein-Barr virus (EBV), with one patient showing EBV enrichment in primary tumour and metastases. EBV was PCR-validated in 80 pairs of CRC primary tumour and their corresponding normal tissues; in 21 of these pairs (26.3%), it was detectable in primary tumours only. The number of viral species was increased and bacterial species decreased in CRCs compared with normal tissues, and we could discriminate primary CRCs from metastases and normal tissues by applying the Hutcheson t-test on the Shannon indices based on viral and bacterial species. Taken together, our results descriptively support hypotheses on microorganisms as potential (co)risk factors of CRC and extend putative suggestions on critical microbiome species in CRC metastasis.

Viruses in colorectal cancer

Increasing evidence suggests that microorganisms might represent at least highly interesting cofactors in colorectal cancer (CRC) oncogenesis and progression. Still, associated mechanisms, specifically in colonocytes and their microenvironmental interactions, are still poorly understood. Although, currently, at least seven viruses are being recognized as human carcinogens, only three of these – Epstein–Barr virus (EBV), human papillomavirus (HPV) and John Cunningham virus (JCV) – have been described, with varying levels of evidence, in CRC. In addition, cytomegalovirus (CMV) has been associated with CRC in some publications, albeit not being a fully acknowledged oncovirus. Moreover, recent microbiome studies set increasing grounds for new hypotheses on bacteriophages as interesting additional modulators in CRC carcinogenesis and progression. The present Review summarizes how particular groups of viruses, including bacteriophages, affect cells and the cellular and microbial microenvironment, thereby putatively contributing to foster CRC. This could be achieved, for example, by promoting several processes – such as DNA damage, chromosomal instability, or molecular aspects of cell proliferation, CRC progression and metastasis – not necessarily by direct infection of epithelial cells only, but also by interaction with the microenvironment of infected cells. In this context, there are striking common features of EBV, CMV, HPV and JCV that are able to promote oncogenesis, in terms of establishing latent infections and affecting p53‐/pRb‐driven, epithelial–mesenchymal transition (EMT)‐/EGFR‐associated and especially Wnt/β‐catenin‐driven pathways. We speculate that, at least in part, such viral impacts on particular pathways might be reflected in lasting (e.g. mutational or further genomic) fingerprints of viruses in cells. Also, the complex interplay between several species within the intestinal microbiome, involving a direct or indirect impact on colorectal and microenvironmental cells but also between, for example, phages and bacterial and viral pathogens, and further novel species certainly might, in part, explain ongoing difficulties to establish unequivocal monocausal links between specific viral infections and CRC.

Exploring polyps to colon carcinoma voyage: can blocking the crossroad halt the sequence?

Colorectal cancer is an important public health concern leading to significant cancer associate mortality. A vast majority of colon cancer arises from polyp which later follows adenoma, adenocarcinoma, and carcinoma sequence. This whole process takes several years to complete and recent genomic and proteomic technologies are identifying several targets involved in each step of polyp to carcinoma transformation in a large number of studies. Current text presents interaction network of targets involved in polyp to carcinoma transformation. In addition, important targets involved in each step according to network biological parameters are also presented. The functional overrepresentation analysis of each step targets and common top biological processes and pathways involved in carcinoma indicate several insights about this whole mechanism. Interaction networks indicate TP53, AKT1, GAPDH, INS, EGFR, and ALB as the most important targets commonly involved in polyp to carcinoma sequence. Though several important pathways are known to be involved in CRC, the central common involvement of PI3K-AKT indicates its potential for devising CRC management strategies. The common and central targets and pathways involved in polyp to carcinoma progression can shed light on its mechanism and potential management strategies. The data-driven approach aims to add valuable inputs to the mechanism of the years-long polyp-carcinoma sequence.

PRESENÇA DO PAPILOMAVIRUS HUMANO TIPO 16 E EXPRESSÃO GÊNICA DA PROTEÍNA P16INK4A E ONCOPROTEÍNA E7 NO CARCINOMA COLORRETAL

Human papillomavirus (HPV) is the agent of the most prevalent sexually transmitted diseases in the world associated with cervix and anal canal cancer. The action of HPV on colorectal carcinogenesis is not yet established.

The role of viruses in adenocarcinoma development

Cancer is a leading public health issue that accounts for million deaths around the world every year. Human cancers contain over 100 types, which are categorized into different groups. Adenocarcinoma is one of those categories of cancer that begins from the glans and involves various tissues such as lung, esophagus, pancreas, prostate and colorectal. A range of risk factors has been identified for the development and progression of adenocarcinomas. One of these risk factors are viruses that serves special mechanisms to affect important host cell factors and tumorigenic pathways, contributing in development and promotion of adenocarcinomas. Here, we summarized the main viruses and their mechanisms implicated in the course of various adenocarcinomas development.

Does human papillomavirus cause human colorectal cancer? Applying Bradford Hill criteria postulates

The role of human papillomavirus (HPV) in human colorectal cancer (CRC) has already been widely investigated worldwide with conflicting results. Although researchers have tried to establish the link between HPV and CRC through a statistical meta-analysis of the previous studies associating HPV with CRC, they failed to establish a more reliable link due to the shortcomings of the statistical meta-analysis. In the present study, we identified population-wide studies relating HPV with CRC through the PubMed search engine. Then, we examined the available data of HPV prevalence in CRC and normal/benign samples and applied the postulates of Bradford Hill criteria on the available evidence to investigate the association between HPV and CRC. The Bradford Hill criteria are very old, reliable and widely accepted for establishing a link between the cause and disease. In addition, to further enhance the reliability of the outcomes, we have also evaluated the methodologies of the previous studies to address the possibility of false-negative and false-positive results. After a careful evaluation of the extracted data against the postulates of Bradford Hill criteria, it was observed that none of the studies fulfil all the major postulates of Bradford Hill criteria for causation including temporality, consistency, biological gradient, experiment, coherence, specificity and analogy. Hence, no causal relationship has been suggested between HPV and CRC patients of the any included population. The results failed to prove the causal relationship between HPV and CRC and suggested HPV as a coparticipant in the pathogenesis of CRC.

Detection of Human papillomavirus and the role of p16INK4a in colorectal carcinomas

INTRODUCTION

Human papillomavirus (HPV) infection is associated with the development of anogenital and head and neck cancers. In recent years a potential role of HPV in colorectal cancer (CRC) has been suggested.

OBJECTIVE

To investigate the presence of HPV in colorectal carcinomas and to study the role of p16INK4a as a marker of transcriptionally active HPV infection. In addition, to investigate the correlation between these findings and the CRC prognostic factors.

METHODS

Case control study with 92 cases of colorectal cancers, 75 controls of normal tissue adjacent to the tumor, and 30 controls of precursor lesions, including polyps and colorectal adenomas. Paraffinized samples were used, HPV detection and genotyping were performed by PCR and reverse hybridization by using the INNO LIPA kit, with SPF10 plus primers. The expression of the p16INK4a protein was investigated using immunohistochemistry. Data analysis was performed using descriptive, univariate statistics and survival curves were calculated by using the Kaplan Meier and log-rank method.

RESULTS

HPV was detected in 13% of the cases and the most prevalent genotype was HPV 16. HPV DNA was not detected in either control groups. The high expression of p16INK4a was observed in 30% of the cases, but it was not associated to the presence of HPV. The overall survival was 53.3% and was influenced by prognostic factors such as later stage, lymph node and distant metastasis.

CONCLUSIONS

Based on these results, HPV is unlikely to be involved in colorectal carcinogenesis and p16INK4a expression is not a relevant marker of transcriptionally active HPV infection in CRC.

Differences in Stage of Cancer at Diagnosis, Treatment, and Survival by Race and Ethnicity Among Leading Cancer Types

IMPORTANCE

Information about stage of cancer at diagnosis, use of therapy, and survival among patients from different racial/ethnic groups with 1 of the most common cancers is lacking.

OBJECTIVE

To assess stage of cancer at diagnosis, use of therapy, overall survival (OS), and cancer-specific survival (CSS) in patients with cancer from different racial/ethnic groups.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included 950 377 Asian, black, white, and Hispanic patients who were diagnosed with prostate, ovarian, breast, stomach, pancreatic, lung, liver, esophageal, or colorectal cancers from January 2004 to December 2010. Data were collected using the Surveillance, Epidemiology, and End Results (SEER) database, and patients were observed for more than 5 years. Data analysis was conducted in July 2018.

MAIN OUTCOMES AND MEASURES

Multivariable logistic and Cox regression were used to evaluate the differences in stage of cancer at diagnosis, treatment, and survival among patients from different racial/ethnic groups.

RESULTS

A total of 950 377 patients (499 070 [52.5%] men) were included in the study, with 681 251 white patients (71.7%; mean [SD] age, 65 [12] years), 116 015 black patients (12.2%; mean [SD] age, 62 [12] years), 65 718 Asian patients (6.9%; mean [SD] age, 63 [13] years), and 87 393 Hispanic patients (9.2%; mean [SD] age, 61 [13] years). Compared with Asian patients, black patients were more likely to have metastatic disease at diagnosis (odds ratio [OR], 1.144; 95% CI, 1.109-1.180; P < .001). Black and Hispanic patients were less likely to receive definitive treatment than Asian patients (black: adjusted OR, 0.630; 95% CI, 0.609-0.653; P < .001; Hispanic: adjusted OR, 0.751; 95% CI, 0.724-0.780; P < .001). White, black, and Hispanic patients were more likely to have poorer CSS and OS than Asian patients (CSS, white: adjusted HR, 1.310; 95% CI, 1.283-1.338; P < .001; black: adjusted HR, 1.645; 95% CI, 1.605-1.685; P < .001; Hispanic: adjusted HR, 1.300; 95% CI, 1.266-1.334; P < .001; OS, white: adjusted HR, 1.333; 95% CI, 1.310-1.357; P < .001; black: adjusted HR, 1.754; 95% CI, 1.719-1.789; P < .001; Hispanic: adjusted HR, 1.279; 95% CI, 1.269-1.326; P < .001).

CONCLUSIONS AND RELEVANCE

In this study of patients with 1 of 9 leading cancers, stage at diagnosis, treatment, and survival were different by race and ethnicity. These findings may help to optimize treatment and improve outcomes.

Human papillomavirus (HPV) 16 infection is not detected in rectal carcinoma

Introduction

Persistence of human papillomavirus (HPV) infections is associated with squamous cell carcinomas of different human anatomic sites. Several studies have suggested a potential role for HPV infection, particularly HPV16 genotype, in rectal cancer carcinogenesis.. The aim of this study was to assess the frequency of oncogenic HPV 16 viral DNA sequences in rectal carcinomas cases retrieved from the pathology archive of Braga Hospital, North Portuga.

Methods

TaqMan-based type-specific real-time PCR for HPV 16 was performed using primers and probe targeting HPV16 E7 region.

Results

Most of the rectal cancer patients (88.5%, n = 206 patients), were symptomatic at diagnosis. The majority of the lesions (55.3%, n = 129) presented malignancies of polypoid/vegetant phenotype. 26.8% (n = 63) had synchronic metastasis at diagnosis. 26.2% (n = 61) patients had clinical indication for neoadjuvant therapy. Most patients with rectal cancer were stage IV (19.7% patients), followed by stage IIA (19.3%) and stage I (18.5%). All cases of the present series tested negative for HPV16.

Conclusion

The total of negative tests for HPV 16 infection is a robust argument to support the assumption that HPV 16 infection, despite of previous evidences, is not involved in rectal cancer carcinogenesis and progression.

The prevalence of HPV infection in rectal cancer - Report from South - Central Poland (Cracow region)

Some studies suggest that HPV infection may be important carcinogenic factor in development of some part of colorectal cancers. However, in the worldwide literature concerning this type of tumours, the great variability in HPV frequency is noticed. In Poland, the incidence of HPV infection in colorectal cancers was examined in five studies so far and their results are also conflicting. Therefore, the aim of the present study was to assess the HPV presence in the group of 120 patients with adenocarcinomas of rectum. HPV infection was assessed on the basis of DNA extracted from collected formalin fixed paraffin embedded tumour specimens. Viral presence was evaluated using two PCR based methods: nested PCR and quantitative PCR (qPCR) with primers specific for HPV16. All HPV positive samples were subjected to virus genotyping using AmoyDx^® Human papillomavirus (HPV) Genotyping Detection Kit and P16 immunostaining. Among 120 evaluated colorectal tumours, HPV DNA was detected in 2 cancers (1.67%) by nested PCR and in 2 (1.67%) tumours by qPCR, including 1 sample diagnosed as HPV positive on the basis of both PCR variants. Two HPV positive cancers had HPV16 infection and other one HPV18. All three tumours with positivity of HPV DNA were P16 negative. In south - central Poland, HPV infection in rectal cancers probably has not influence on rectal carcinogenesis.

Human papillomavirus and p16 in squamous cell carcinoma and intraepithelial neoplasia of the vagina

We estimated the overall and type-specific prevalence of human papillomavirus (HPV) and p16 overexpression in vaginal cancer and vaginal intraepithelial neoplasia (VaIN). We conducted a systematic search of PubMed, Embase and Cochrane Library to identify studies published between 1986 and 2017 using PCR-based or Hybrid Capture 2 tests to evaluate the presence of HPV DNA and/or using any method to detect p16 overexpression in VaIN, vaginal squamous cell carcinoma (VaSCC), or other types of vaginal cancer. Applying a random effects model, we estimated the pooled prevalence of HPV and p16 overexpression along with 95% confidence intervals (CIs). The I² statistic was used to assess heterogeneity. We included 26 studies, reporting HPV prevalence and six studies evaluating p16 overexpression. The pooled HPV prevalences in VaSCC (n = 593) and VaIN (n = 1,374) were 66.7% (95% CI = 54.7-77.8) and 85.2% (95% CI = 78.2-91.0), respectively. Substantial inter-study heterogeneity was observed, and analyses stratified on geographic region, type of tissue, HPV detection method or PCR primer type did not fully explain the observed heterogeneity. The most predominant HPV type among the HPV positive VaSCC and VaIN cases was HPV16, followed by HPV33, and HPV45 (in VaIN) and HPV18, and HPV33 (in VaSCC). In pooled analyses, 89.9% (95% CI = 81.7-94.6) of HPV positive and 38.9% (95% CI = 0.9-90.0) of HPV negative vaginal cancers were positive for p16 overexpression. Our findings suggest that vaccination against HPV might prevent a substantial proportion of vaginal neoplasia and highlight the need for further studies of the possible clinical value of p16 testing in these patients.

Papillomavirus can be transmitted through the blood and produce infections in blood recipients: Evidence from two animal models

Human papillomaviruses (HPV) contribute to most cervical cancers and are considered to be sexually transmitted. However, papillomaviruses are often found in cancers of internal organs, including the stomach, raising the question as to how the viruses gain access to these sites. A possible connection between blood transfusion and HPV-associated disease has not received much attention. Here we show, in rabbit and mouse models, that blood infected with papillomavirus yields infections at permissive sites with detectable viral DNA, RNA transcripts, and protein products. The rabbit skin tumours induced via blood infection displayed decreased expression of SLN, TAC1, MYH8, PGAM2, and APOBEC2 and increased expression of SDRC7, KRT16, S100A9, IL36G, and FABP9, as seen in tumours induced by local infections. Furthermore, we demonstrate that blood from infected mice can transmit the infection to uninfected animals. Finally, we demonstrate the presence of papillomavirus infections and virus-induced hyperplasia in the stomach tissues of animals infected via the blood. These results indicate that blood transmission could be another route for papillomavirus infection, implying that the human blood supply, which is not screened for papillomaviruses, could be a potential source of HPV infection as well as subsequent cancers in tissues not normally associated with the viruses.

Human papillomavirus infection and colorectal cancer in the Chinese population: a meta-analysis

AIM

Human papillomavirus (HPV) infection has been reported in colorectal cancer in many studies. We conducted a meta-analysis to assess the association between HPV infection and colorectal cancer/adenomas in the Chinese population.

METHOD

Relevant studies up to January 2018 were searched in PubMed, EMBASE, China National Knowledge Infrastructure and the Wanfang database. We used a random effects model to determine the prevalence of HPV and odds ratios (ORs) with 95% confidence intervals (CIs). The I² statistic and P-value from the Cochrane Q-test were used to describe the heterogeneity.

RESULTS

Ten case-control studies involving 766 colorectal cancer patients and 470 controls were included in the meta-analysis. Among the colorectal cancer patients, the pooled prevalence was 0.45 (95% CI 0.36-0.53). The pooled estimate for OR was 10.78 (95% CI 4.22, 27.53). Among the 193 patients with colorectal adenoma, the pooled prevalence and OR were 0.31 (95% CI 0.24-0.37) and 2.03 (95% CI 0.79, 5.26), respectively. The prevalence of HPV 16 and HPV 18 among HPV-positive cancers ranged from 57.9% to 100% and 0% to 39.7%, respectively.

CONCLUSION

The results indicated that HPV infection, especially HPV 16 and HPV 18, is associated with colorectal cancer in the Chinese population.

Trends in colorectal cancer incidence among younger adults-Disparities by age, sex, race, ethnicity, and subsite

Millennials (ages 18-35) are now the largest living generation in the US, making it important to understand and characterize the rising trend of colorectal cancer incidence in this population, as well as other younger generations of Americans. Data from the New Jersey State Cancer Registry (n = 181 909) and Surveillance, Epidemiology, and End Results program (n = 448 714) were used to analyze invasive CRC incidence trends from 1979 to 2014. Age, sex, race, ethnicity, subsite, and stage differences between younger adults (20-49) and screening age adults (≥50) in New Jersey (NJ) were examined using chi-square; and, we compared secular trends in NJ to the United States (US). Whites, men, and the youngest adults (ages 20-39) are experiencing greater APCs in rectal cancer incidence. Rates among younger black adults, overall, were consistently higher in both NJ and the US over time. When compared to older adults, younger adults with CRC in NJ were more likely to be: diagnosed at the late stage, diagnosed with rectal cancer, male, non-white, and Hispanic. Invasive CRC incidence trends among younger adults were found to vary by age, sex, race, ethnicity, and subsite. Large, case-level, studies are needed to understand the role of genetics, human papillomavirus (HPV), and cultural and behavioral factors in the rise of CRC among younger adults. Provider and public education about CRC risk factors will also be important for preventing and reversing the increasing CRC trend in younger adults.

Disease Characteristics, Clinical Management, and Outcomes of Young Patients With Colon Cancer: A Population-based Study

INTRODUCTION

The incidence of colorectal cancer in young patients has been increasing. We evaluated whether the disease characteristics, management, and outcomes of patients with colon cancer differ among patients aged ≤ 40 years compared with those of older patients.

MATERIALS AND METHODS

Using the Ontario Cancer Registry, all cases of colon cancer (stage I, II, III) treated with surgery in Ontario from 2002 to 2008 were identified. The electronic medical records of treatment were used to identify the use of surgery and adjuvant chemotherapy (ACT). The pathology reports were obtained for a random 25% sample of all cases. A Cox model was used to identify the factors associated with overall (OS) and cancer-specific survival (CSS).

RESULTS

The study population included 6775 patients. The age distribution was 2%, 5%, 14%, and 79% for patients aged ≤ 40, 41 to 50, 51 to 60, and > 60 years, respectively. Compared with patients aged > 60 years, younger patients (age ≤ 40 years) were more likely to have lymphovascular invasion (35% vs. 27%; P = .005), T3/T4 tumors (88% vs. 79%; P = .005) and lymph node-positive disease (58% vs. 41%; P < .001). The stage distribution varied by age: stage I, 8% versus 19%; stage II, 34% versus 40%; and stage III, 58% versus 41% for those aged ≤ 40 years versus those aged > 60 years, respectively (P < .001). ACT was delivered more often to patients aged ≤ 40 years than to those aged > 60 years for stage II (50% vs. 13%; P < .001) and stage III (≥ 92% vs. 57%; P < .001) disease. The adjusted OS (hazard ratio [HR], 0.32; 95% confidence interval [CI], 0.21-0.49) and CSS (HR, 0.41; 95% CI, 0.26-0.64) were superior for patients aged ≤ 40 years compared with the OS and CSS for those aged > 60 years.

CONCLUSION

Young patients with colon cancer have more aggressive and advanced disease but improved outcomes compared with older patients.

A viral map of gastrointestinal cancers

Cancers of the gastrointestinal tract (GIT) are expected to account for approximately 20% of all cancers in 2017. Apart from their high incidence, GIT cancers show high mortality rates, placing these malignancies among the most prominent public health issues of our time. Cancers of the GIT are the result of a complex interplay between host genetic factors and environmental factors and frequently arise in the context of a continued active inflammatory response. Several tumor viruses are able to elicit such chronic inflammatory responses. In fact, several viruses have an impact on GIT tumor initiation and progression, as well as on patients' response to therapy and prognosis, through direct and indirect mechanisms. In this review, we have gathered information on different viruses' rates of infection, viral-driven specific carcinogenesis mechanisms and viral-related impact on the prognosis of cancers of the GIT (specifically in organs that have an interface with the environment - esophagus, stomach, intestines and anus). Overall, while some viral infections show a strong causal relation with specific gastrointestinal cancers, these represent a relatively small fraction of GIT malignancies. Other types of cancer, like Esophageal Squamous Cell Carcinoma, require further studies to confirm the carcinogenic role of some viral agents.

Frequency of human papillomavirus infection in patients with gastrointestinal cancer

INTRODUCTION AND AIM

Cancer is the result of the interaction of genetic and environmental factors. It has recently been related to viral infections, one of which is human papillomavirus. The aim of the present study was to describe the frequency of human papillomavirus infection in patients with digestive system cancers.

MATERIALS AND METHODS

A prospective, multicenter, observational study was conducted on patients with gastrointestinal cancer at 2public healthcare institutes in Veracruz. Two tumor samples were taken, one for histologic study and the other for DNA determination of human papillomavirus and its genotypes. Anthropometric variables, risk factors, sexual habits, tumor location, and histologic type of the cancer were analyzed. Absolute and relative frequencies were determined using the SPSS version 24.0 program.

RESULTS

Fifty-three patients were studied. They had gastrointestinal cancer located in: the colon (62.26%), stomach (18.87%), esophagus (7.55%), rectum (7.55%), and small bowel (3.77%). Human papillomavirus was identified in 11.32% of the patients, 66.7% of which corresponded to squamous cell carcinoma and 33.3% to adenocarcinoma. Only genotype 18 was identified. Mean patient age was 61.8±15.2 years, 56.60% of the patients were men, and 43.40% were women. A total of 15.8% of the patients had a family history of cancer and 31.6% had a personal history of the disease, 38.6% were tobacco smokers, and 61.4% consumed alcohol. Regarding sex, 5.3% of the patients said they were homosexual, 3.5% were bisexual, 29.8% engaged in oral sex, and 24.6% in anal sex.

CONCLUSIONS

Our study showed that human papillomavirus infection was a risk factor for the development of gastrointestinal cancer, especially of squamous cell origin.

Evaluation of HPV DNA positivity in colorectal cancer patients in Kerman, Southeast Iran

Background:

The HPV virus is known to be oncogenic and associations with many cancers has been proven. Although many studies have been conducted on the possible relationship with colorectal cancer (CRC), a definitive role of the virus has yet to be identified.

Method:

In this cross-sectional study, the frequency of HPV positivity in CRC samples in Kerman was assessed in 84 cases with a mean age of 47.7 ± 12.5 years over two years. Qualitative real time PCR was performed using general primers for the L1 region of HPV DNA.

Results:

Out of 84 CRC samples, 19 (22.6%), proved positive for HPV DNA. Genotyping of positive samples showed all of these to be of high risk HPV type. Prevalence of HPV infection appears to depend geographic region, life style, diet and other factors.

Conclusion:

In our location frequency of CRC is low, and this limited the sample size for evaluation of HPV DNA. The most prevalent types were HPV types 51 and 56. While HPV infection may play an important role in colorectal carcinogenesis, this needs to be assessed in future studies.

Role of viruses in gastrointestinal cancer

Gastrointestinal cancers are a global public health problem, which represent a vast majority of all cancer-caused deaths in both men and women. On the other hand, viral pathogens have been long implicated as etiological factors in the onset of certain human cancers, including gastrointestinal tumors. In this regard, Human Papilloma Virus (HPV), Epstein-Barr Virus (EBV), and John Cunningham Virus (JCV) have been more strongly suggested to be involved in gastrointestinal carcinogenesis; so that, the association of HPV with oropharyngeal and anal cancers and also the association of EBV with gastric cancer have been etiologically confirmed by epidemiological and experimental investigations. Although, the association of other viruses is less evident, but may rely on co-factors for their oncogenic roles. Therefore, to improve the prevention and treatment of these classes of cancer, their association with viral agents as potential risk factors should be investigated with care. In this respect, the present review has focused on the existing literature on the subject of viral involvement in gastrointestinal tumorgenesis, by covering and discussing various gastrointestinal cancers, corresponding viral agents and their oncogenic aspects and then summarizing evidences either supporting or rejecting a causal role of these pathogens in gastrointestinal malignancies.

Human papillomaviruses in colorectal cancers: A case-control study in western patients

BACKGROUND

Colorectal cancer (CRC) is one of the most common cancers. As in other cancer locations, the involvement of human papillomaviruses (HPV) has been suggested but remains highly debated with wide differences among reported prevalence of HPV infection in CRCs.

AIM

To determine the actual prevalence of high risk HPV16 and 18 in a large case-control study.

METHODS

CRC specimens were used for analysis of both tumor and distant healthy tissue. As a non-malignant control group, samples from sigmoid diverticulosis resections were studied. Detection of HPV16 and HPV18 DNA was performed using a real time polymerase chain reaction (qPCR). Ten percent of tumor samples were also randomly subjected to a complete HPV genotyping using the INNO-LiPA technique.

RESULTS

467 samples were analyzed: 217 tumor samples from 210 CRCs, 210 distant healthy tissue samples, and 40 sigmoid samples. HPV18 DNA was never amplified and HPV16 was amplified only three times in tumor tissues with viral loads under or at the limit of quantification. New extraction from the same tumor blocks for these samples revealed no HPV with qPCR and INNO-Lipa assays.

CONCLUSION

With adequate procedures and reliable techniques, no HPV was detected in the largest case-control study so far, bringing more evidence on the absence of involvement of HPV in CRCs.

Molecular evidence of high-risk human papillomavirus infection in colorectal tumours from Cuban patients

The association between colorectal cancer and human papillomavirus (HPV) infection is still unproven. The aim of this study was to investigate the presence of high-risk HPV (HR-HPV) DNA in colorectal tissues from Cuban patients. A total of 63 colorectal formalin-fixed paraffin-embedded tissues were studied (24 adenocarcinoma, 18 adenoma, and 21 colorectal tissues classified as benign colitis). DNA from colorectal samples was analysed by quantitative real-time polymerase chain reaction to detect the most clinically relevant high HR-HPV types (HPV-16, -18, -31, -33, -45, -52, and -58). Associations between histologic findings and other risk factors were also analysed. Overall, HPV DNA was detected in 23.8% (15/63) of the samples studied. Viral infections were detected in 41.7% of adenocarcinoma (10/24) and 27.7% of adenoma cases (5/18). HPV DNA was not found in any of the negative cases. An association between histological diagnosis of adenocarcinoma and HPV infection was observed (odd ratio = 4.85, 95% confidence interval = 1.40-16.80, p = 0.009). The only genotypes identified were HPV 16 and 33. Viral loads were higher in adenocarcinoma, and these cases were associated with HPV 16. This study provides molecular evidence of HR-HPV infection in colorectal adenocarcinoma tissues from Cuban patients.

Human papillomavirus as a potential risk factor for gastric cancer: a meta-analysis of 1,917 cases

Background

Human papillomaviruses (HPVs) are causally associated with the tumorigenesis of several classes of cancers. However, the prevalence of HPV in gastric cancer (GC) has not yet been systematically reviewed. Hence, a meta-analysis was conducted to estimate the HPV prevalence in patients with GC, and its potential etiologic significance was assessed.

Methods

The pooled HPV prevalence and 95% confidence intervals (CIs) were estimated among all GC patients. Heterogeneity was described by using the I² statistic. Sources of heterogeneity were explored by meta-regression and stratified analyses. The meta-influence was applied to evaluate the influence of a single study on the pooled estimates. Odds ratios (ORs) and 95% CIs were computed for case–control studies. For research providing clinicopathological parameters of age, sex, pathological, differentiated, and clinical stages, and HPV subtypes, the corresponding pooled ORs and 95% CIs were also calculated.

Results

Thirty studies were included in the current meta-analysis, involving 1,917 patients with GC and 576 controls. The pooled HPV prevalence was 28.0% (95% CI: 23.2%, 32.7%) among all the patients with GC, and the I² was 96.9% (P<0.001). A pooled OR of 7.388 (95% CI: 3.876, 14.082) was achieved based on 15 case–control studies (I²=56.7%, P=0.004). Moreover, the HPV prevalence was significantly higher in patients from China than in those from non-Chinese regions (31% vs 9%, I²=95.0%, P<0.001). The pooled prevalence of HPV16 was 21% in GC tissues, and the pooled prevalence of HPV18 was 7% with an OR of 3.314 (95% CI =1.617, 6.792). HPV16 was 3 times more frequently detected than HPV18.

Conclusion

HPV could play a potential role in the pathogenesis of GC. A causal relationship can be confirmed only by detecting HPV in the cells of GC precursor lesions (gastric dysplasia or adenoma). In addition, this study might be beneficial for expounding the potential etiologic significance of molecular mechanism of gastric tumorigenesis and providing opinions regarding precautionary measures.

Human papillomavirus and gastrointestinal cancer: A review

Human papillomavirus (HPV) is one of the most common sexually transmitted infections worldwide. Exposure to HPV is very common, and an estimated 65%-100% of sexually active adults are exposed to HPV in their lifetime. The majority of HPV infections are asymptomatic, but there is a 10% chance that individuals will develop a persistent infection and have an increased risk of developing a carcinoma. The International Agency for Research on Cancer has found that the following cancer sites have a strong causal relationship with HPV: cervix uteri, penis, vulva, vagina, anus and oropharynx, including the base of the tongue and the tonsils. However, studies of the aetiological role of HPV in colorectal and esophageal malignancies have conflicting results. The aim of this review was to organize recent evidence and issues about the association between HPV infection and gastrointestinal tumours with a focus on esophageal, colorectal and anal cancers. The ultimate goal was to highlight possible implications for prognosis and prevention.

Tracking vaginal, anal and oral infection in a mouse papillomavirus infection model

Noninvasive and practical techniques to longitudinally track viral infection are sought after in clinical practice. We report a proof-of-principle study to monitor the viral DNA copy number using a newly established mouse papillomavirus (MmuPV1) mucosal infection model. We hypothesized that viral presence could be identified and quantified by collecting lavage samples from cervicovaginal, anal and oral sites. Nude mice infected at these sites with infectious MmuPV1 were tracked for up to 23 weeks starting at 6 weeks post-infection. Viral DNA copy number was determined by SYBR Green Q-PCR analysis. In addition, we tracked viral DNA load through three complete oestrous cycles to pinpoint whether there was a correlation between the DNA load and the four stages of the oestrous cycle. Our results showed that high viral DNA copy number was reproducibly detected from both anal and cervicovaginal lavage samples. The infection and disease progression were further confirmed by histology, cytology, in situ hybridization, immunohistochemistry and transmission electron microscopy. Interestingly, the viral copy number fluctuated over the oestrous cycle, with the highest level at the oestrus stage, implying that multiple sampling might be necessary to provide a reliable diagnosis. Virus DNA was detected in oral lavage samples at a later time after infection. Lower viral DNA load was found in oral samples when compared with those in anal and vaginal tracts. To our knowledge, our study is the first in vivo study to sequentially monitor papillomavirus infection from mucosal anal, oral and vaginal tracts in a preclinical model.

Viral infections and colorectal cancer: a systematic review of epidemiological studies

Numerous studies have found the presence of viral DNA in colorectal tumor tissues. However, whether viral infections contribute to the risk of colorectal cancer (CRC) is still under debate. We aimed to provide an overview of published epidemiological studies on the association between viral infections and CRC. A systematic literature search was performed in PubMed to find relevant studies published until 8 May 2014. Information collected included study population, sample type, laboratory method and prevalence of viral infection in cancer or precancer patients and controls. We found 41 studies that fulfilled the selection criteria, all of which had cross-sectional or case-control designs, and most of which were of small to moderate size. Viral infections included human papillomaviruses (HPV), human polyomaviruses, human herpesviruses, human bocavirus and Inoue-Melnick virus. Inconsistent results were observed across studies. Many studies reported higher viral DNA prevalence in tumor tissues than in normal noncancerous tissues either in the same patients or in CRC-free controls. However, potential contamination or temporal sequence of the infection and cancer development were often unclear. Seroprevalence studies assessing antibody titers indicative of viral infections did not find statistically significant differences between CRC cases and healthy controls. Overall published evidence on the role of viral infections in CRC etiology remains limited. Given the potential importance of viral infections and their implication for prevention, there is a strong need for large, methodologically rigorous epidemiological studies.

Human papillomavirus infection correlates with inflammatory Stat3 signaling activity and IL-17 level in patients with colorectal cancer

Background

Colorectal cancer (CRC) is a major burden of public health and healthcare worldwide. Microbiota has been suggested in promoting chronic inflammation in the intestine which, in turn, promotes tumor development. This study focuses on possible correlations of human papillomavirus (HPV) infection with proinflammatory Stat3 signaling activities and the resulting levels of its downstream proinflammatory cytokine IL-17 in CRC patients.

Methods

HPV was examined using HPV Genotyping Chip technology and constitutively active Stat3 (p-Stat3) and IL-17 levels were tested using immunohistochemistry (IHC) in paraffin-embedded cancerous and adjacent normal tissues (ANT) from a cohort of 95 CRC patients. Correlation analyses were performed between HPV infection and clinicopathological characteristics, Stat3 activities and IL-17 levels among these CRC patients.

Results

Three major findings were observed: (1) HPV infection existed in a high rate of CRC cases (48.4%, 46/95), of which 45 cases (45/46, 97.8%) were high-risk HPV16-positive and only one case was HPV53-positive. (2) HPV infection correlated with poorer clinical stages (III+IV) of CRC. (3) HPV infection strongly correlated with both constitutively higher Stat3 activities (P<0.01) and higher IL-17 levels (P<0.01) only in CRC tissues but not in ANT tissues.

Conclusions

HPV infection is common in CRC patients suggesting potentially preventive effectiveness of HPV vaccination among high-risk young individuals. We have for the first time revealed a tri-lateral relationship among HPV infection, constitutive Stat3 activity and IL-17 level, whose collaborative act may orchestrate a proinflammatory microenvironment in the colorectum that, in turn, may promote carcinogenesis and possibly facilitate progression of CRC.