Association of human papillomavirus and colon neoplasms

HPV-associated cancers: insights into the mechanistic scenario and latest updates

Cancer and related diseases are the second leading cause of death worldwide. The human papillomavirus (HPV) is an infectious agent that can be spread mainly through sexual contact and has been linked to several malignancies in both sexes. HPV is linked to almost all cases of cervical cancer. It is also linked to many head and neck cancer (HNC) cases, especially oropharyngeal cancer. Also, some HPV-related cancers, like vaginal, vulvar, penile, and anal cancers, are related to the anogenital area. Over the past few decades, testing for and preventing cervical cancer has improved, but anogenital cancers are still harder to confirm. HPV16 and HPV18 have been extensively researched due to their significant carcinogenic potential. The products of two early viral genes, E6 and E7, have been identified as playing crucial roles in cellular transformation, as emphasized by biological investigations. The complete characterization of numerous mechanisms employed by E6 and E7 in undermining the regulation of essential cellular processes has significantly contributed to our comprehension of HPV-induced cancer progression. This review focuses on the various types of cancers caused by HPV infection and also sheds light on the signaling cascades involved in the same.

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.

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.

The Roles of the Virome in Cancer

Viral infections as well as changes in the composition of the intestinal microbiota and virome have been linked to cancer. Moreover, the success of cancer immunotherapy with checkpoint inhibitors has been correlated with the intestinal microbial composition of patients. The transfer of feces-which contain mainly bacteria and their viruses (phages)-from immunotherapy responders to non-responders, known as fecal microbiota transplantation (FMT), has been shown to be able to convert some non-responders to responders. Since phages may also increase the response to immunotherapy, for example by inducing T cells cross-reacting with cancer antigens, modulating phage populations may provide a new avenue to improve immunotherapy responsiveness. In this review, we summarize the current knowledge on the human virome and its links to cancer, and discuss the potential utility of bacteriophages in increasing the responder rate for cancer immunotherapy.

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.

Viruses in Cancers of the Digestive System: Active Contributors or Idle Bystanders?

The human virome, which is a collection of all the viruses that are present in the human body, is increasingly being recognized as an essential part of the human microbiota. The human gastrointestinal tract and related organs (e.g., liver, pancreas, and gallbladder)-composing the gastrointestinal (or digestive) system-contain a huge number of viral particles which contribute to maintaining tissue homeostasis and keeping our body healthy. However, perturbations of the virome steady-state may, both directly and indirectly, ignite/sustain oncogenic mechanisms contributing to the initiation of a dysplastic process and/or cancer progression. In this review, we summarize and discuss the available evidence on the association and role of viruses in the development of cancers of the digestive system.

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.

Gene Expression Analysis of Human Papillomavirus-Associated Colorectal Carcinoma

PURPOSE

Human papillomavirus (HPV) antigens had been found in colorectal cancer (CRC) tissue, but little evidence demonstrates the association of HPV with oncogene mutations in CRC. We aim to elucidate the mutated genes that link HPV infection and CRC carcinogenesis.

METHODS

Cancerous and adjacent noncancerous tissues were obtained from CRC patients. HPV antigen was measured by using the immunohistochemical (IHC) technique. The differentially expressed genes (DEGs) in HPV-positive and HPV-negative tumor tissues were measured by using TaqMan Array Plates. The target genes were validated with the qPCR method.

RESULTS

15 (31.9%) cases of CRC patients were observed to be HPV positive, in which HPV antigen was expressed in most tumor tissues rather than in adjacent noncancerous tissues. With TaqMan Array Plates analyses, we found that 39 differentially expressed genes (DEGs) were upregulated, while 17 DEGs were downregulated in HPV-positive CRC tissues compared with HPV-negative tissues. Four DEGs (MMP-7, MYC, WNT-5A, and AXIN2) were upregulated in tumor vs. normal tissues, or adenoma vs. normal tissue in TCGA, which was overlapped with our data. In the confirmation test, MMP-7, MYC, WNT-5A, and AXIN2 were upregulated in cancerous tissue compared with adjacent noncancerous tissue. MYC, WNT-5A, and AXIN2 were shown to be upregulated in HPV-positive CRC tissues when compared to HPV-negative tissues.

CONCLUSION

HPV-encoding genome may integrate into the tumor genomes that involved in multiple signaling pathways. Further genomic and proteomic investigation is necessary for obtaining a more comprehensive knowledge of signaling pathways associated with the CRC carcinogenesis.

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.

Detection of human papillomavirus infection by molecular tests and its relation to colonic polyps and colorectal cancer

Objectives:

To prospectively examine the association between human papilloma virus (HPV) colonization of the colonic mucosa and the development of colorectal polyps (CRPs), and colorectal cancer (CRC) in Saudi Arabia.

Methods:

A case control study was performed between January 2013 and December 2014. All eligible patients underwent standard diagnostic colonoscopy. Patients with polyps or colorectal cancer were considered cases, while those with any other endoscopic findings were controls. Biopsy samples from polyps and tumors, and/or from normal colonic mucosa were acquired. Human papilloma virus colonization was detected using a hybrid capture technique of samples taken from both normal tissue, and CRPs and CRC. The association between HPV and CRPs/CRC was evaluated.

Results:

A total of 132 patients were recruited. The mean age was 53 (±15.9) years. Sixty patients had endoscopically detectable CRPs/CRC, and 72 had either inflammation or normal endoscopic evaluations. Only 4 (0.8%) of the 132 samples that were collected and analyzed were positive for the HPV gene. Statistical analysis did not identify any significant association between HPV colonization and the presence of CRPs/CRC. The only significant predictor of detecting CRPs/CRC on colonoscopy was symptomatic presentation (odds ratio=11.072, 95% confidence interval 4.7-26.2, p<0.001).

Conclusion:

Human papilloma virus colonic colonization is rare in Saudi Arabia. An association between HPV colonization and CRP/CRC development could not be identified in this cohort of patients.

High Prevalence of Human Papillomavirus in Colorectal Cancer in Hispanics: A Case-Control Study

The role of Human Papillomavirus (HPV) in colorectal carcinogenesis remains elusive. Based on the high incidence of HPV-associated malignancies among Puerto Rican Hispanics, this study aimed to assess the prevalence of HPV infection and viral integration in colorectal tissues in order to evaluate its putative role in colorectal cancer (CRC). In this case-control study, the prevalence of HPV infection in CRC (cases n = 45) and normal colon mucosa from cancer-free subjects (controls n = 36) was assessed by a nested PCR strategy. HPV-16 genotyping was performed in HPV-positive tissues and the physical status of the HPV-16 genome was determined by E2 detection. HPV was detected in 19 of 45 (42.2%) CRC cases (mean age 61.1 ± 10.7 years, 24 males) and in 1 of 36 (2.8%) controls (mean age 60.9 ± 9.6 years, 24 males) with an OR = 25.58 (95% CI 3.21 to 203.49). HPV-16 was detected in 63.2% of the HPV-positive colorectal tumors; genome integration was observed in all HPV-16 positive cases. This is the first report showing the high prevalence of HPV infections in Caribbean Hispanic colorectal tumors. Despite evidence of HPV integration into the host genome, further mechanistic analysis examining HPV oncoprotein expression and the putative role of these oncoproteins in colorectal carcinogenesis is warranted.

Lack of association between human papillomavirus infection and colorectal cancer

Introduction

Colorectal cancer is the third leading cause of cancer-related deaths worldwide, with nearly one million new cases identified annually. Different factors might cause colorectal cancer, one of the most prevalent cancers among both men and women. Viral aetiology in cancerous malignancies is a very important issue and so far a number of viral strains have been identified as tumour oncogene viruses. Viral infections, such as human papillomavirus (HPV), have recently been suggested as a risk factor for colorectal cancer. However, the aetiology of the disease is still unknown.

Aim

To assessed the association between HPV infection and colorectal cancer.

Material and methods

In this study, 50 cancer tissue samples and 50 samples without colon cancer were studied in order to identify HPV through polymerase chain reaction (PCR). Of 42 adenocarcinomas, 10 were well differentiated, 30 moderated differentiated, and 2 were poorly differentiated. DNA extraction was verified by beta globin gene amplification; specific PCR was carried out based on HPV L1 consensus primers MY09/MY11.

Results

HPV DNA was not identified in any of the normal, adenocarcinoma, or adenoma samples.

Conclusions

In contrast with previous studies, the current research failed to establish a relationship between HPV infection and the incidence of colon cancer. Considering the existing inconsistencies, it is recommended that further studies be conducted with larger sample size.

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.

Carcinogenic viruses and solid cancers without sufficient evidence of causal association

Viral infections are important risk factors for tumor development in humans. Selected types of cancers, either lymphomas or carcinomas, for which there is sufficient evidence in humans of a causal association with specific viruses, have been identified. Experimental and clinical data on the possible association of other tumor types and carcinogenic viruses are presently controversial. In this article, we review the current evidence on the relationship between breast, colorectal and lung cancers and carcinogenic viruses. The majority of the publications reviewed do not provide definitive evidence that the viruses studied are associated with breast, colon and lung cancers. However, since this association may be clinically relevant for some tumor subtypes (i.e., lung cancer and papillomaviruses), there is an urgent need for further investigation on this topic. Using innovative laboratory techniques for viral detection on well-defined tumor types, National and International networks against cancer should encourage and organize concerted research programs on viruses and solid cancer association.

Human papillomavirus infection and colorectal cancer risk: a meta-analysis

AIM

Human papillomavirus (HPV) infection is associated with cervical cancer, but whether it is involved in colorectal carcinogenesis is controversial. We conducted a meta-analysis to evaluate the association between HPV and colorectal adenocarcinoma.

METHOD

A search of the MEDLINE database was performed using the MESH terms 'HPV', 'human papillomavirus', and 'colon cancer', 'rectal cancer', 'colorectal cancer'. The prevalence of HPV infection in colorectal cancer was estimated by pooling data from 16 studies (involving 1436 patients) published up to July 2012, taking into consideration methodological heterogeneity between studies. The association of HPV with colorectal cancer risk was estimated from case-control studies.

RESULTS

The HPV overall prevalence was 31.9% (95% CI: 19.3-47.9). It was lowest in Europe (14.1%, 95% CI: 4.9-34.1) and highest in South America (60.8%, 95% CI: 42.7-76.4). Eight studies presented the results of HPV typing in 302 HPV-positive colorectal carcinomas. HPV 18 was the virus more frequently found in colorectal cancer cases from Asia (73.34%, 95% CI: 44.9-90.7) and Europe (47.3%, 95% CI: 34.5-60.4). In contrast, HPV 16 was more prevalent in colorectal tumours from South America (58.3%, 95% CI: 45.5-69.9). The analysis of five case-control studies showed an increase in colorectal carcinoma risk with HPV positivity (OR = 10.04; 95% CI: 3.7-27.5).

CONCLUSION

The results provide quantitative evidence for an association between HPV infection and colorectal cancer risk.

Pathogen-driven gastrointestinal cancers: Time for a change in treatment paradigm?

The regulation of cancerous tumor development is converged upon by multiple pathways and factors. Besides environmental factors, gastrointestinal (GI) tract cancer can be caused by chronic inflammation, which is generally induced by bacteria, viruses, and parasites. The role of these inducers in cancer development, cell differentiation and transformation, cell cycle deregulation, and in the expression of tumor-associated genes cannot be ignored. Although Helicobacter pylori activates many oncogenic pathways, particularly those in gastric and colorectal cancers, the role of viruses in tumor development is also significant. Viruses possess significant oncogenic potential to interfere with normal cell cycle control and genome stability, stimulating the growth of deregulated cells. An increasing amount of recent data also implies the association of GI cancers with bacterial colonization and viruses. This review focuses on host-cell interactions that facilitate primary mechanisms of tumorigenesis and provides new insights into novel GI cancer treatments.

Human papillomavirus and colorectal cancer: evidences and pitfalls of published literature

PURPOSE

The aim of this study is to review published literature regarding a possible role of human papillomavirus (HPV) infection in colorectal cancer in order to understand if HPV infection plays an active role in colorectal carcinogenesis and to highlight evidences and pitfalls of published studies.

METHODS

We reviewed literature by searching PubMed, Ovid, and the Cochrane databases for published series investigating HPV and colorectal cancer from 1988 to date.

RESULTS

Twenty-one studies investigating a possible correlation between HPV infection and colon cancer have been published. We reviewed 15 case-control studies and six studies investigating a possible role for HPV virus in colorectal carcinogenesis. HPV was detected in the majority of reported series with a significant difference in HPV infection between tumors and disease-free controls or tumor-adjacent tissue; the HPV mean detection rate within carcinomas was 41.7%, comparing to a mean detection rate of 32.8% in adjacent colic mucosae, and 5.8% in disease-free controls (Chi-square test, p = 0.001). The correlation between HPV infection and c-myc amplification, k-ras mutation, and p53 polymorphism or mutations has been investigated; however, the possible role of HPV in colorectal carcinogenesis was not defined.

CONCLUSIONS

HPV has been detected in the majority of reported series, but published literature lacks in definitive data regarding standard methods of investigation and stratification of groups and population. These data encourage further studies with the aim to investigate the presence of the virus in larger series, its possible role in oncogenesis, the integration in host genome, the expression of viral oncoproteins, the mutations in HPV positive cancers and routes of colon infection (hematologic/lymphatic spreading or perineal diffusion).

Infectious causes of colorectal cancer

Colorectal cancer is a major cause of cancer-related morbidity and mortality in the United States and many other regions of the world. Our understanding of the pathogenesis of colorectal cancer, from the precursor adenomatous polyp to adenocarcinoma, has evolved rapidly. Colorectal carcinogenesis is a sequential process characterized by the accumulation of multiple genetic and molecular alterations in colonic epithelial cells. However, the development of colorectal cancer involves more then just a genetic predisposition. External or environmental factors presumably play a significant role, and inflammatory bowel diseases, obesity, alcohol consumption, and a diet high in fat and low in fiber have all been implicated as risk factors for the development of either colonic adenomas or carcinomas. We are becoming increasingly aware of microbes as causes of malignancies. This article reviews the various microbes that have been associated with the development of colorectal carcinomas.

Detection of HPV and the role of p16INK4A overexpression as a surrogate marker for the presence of functional HPV oncoprotein E7 in colorectal cancer

Background

Based on the well-recognized etiological role of human papillomavirus (HPV) in cervical, anogenital and oropharyngeal carcinogenesis, a potential role of HPV in colorectal carcinogenesis has been suggested. For that reason, the aim of the present study was to investigate the presence of HPV DNA in colorectal carcinomas (CRC) and to study overexpression of p16^INK4A as a marker for the presence of an active HPV oncoprotein E7. These findings were correlated with clinical and pathological prognostic factors of CRC.

Methods

The presence of HPV was assessed using a multiplex PCR system of 10 non-biotinylated primers. The amplified fragments of HPV positive samples were further analyzed by a highly sensitive, broad spectrum SPF10 PCR and subsequently genotyped using reverse hybridization in a line probe assay.

P16^INK4A protein expression was investigated in a subset of 90 (30 HPV positive and 60 HPV negative) CRC samples by immunohistochemistry.

Results

HPV DNA was found in 14.2% of the CRC samples with HPV16 as the most prevalent type. No significant differences in clinical and pathological variables were found between HPV positive and negative CRCs, except for age. HPV positive patients were significantly younger (p = 0.05). There was no significant correlation between the presence of HPV and overexpression of p16^INK4A (p = 0.325).

Conclusions

In conclusion, the presence of oncogenic HPV DNA in a small cohort of CRC samples may suggest that HPV may be involved in the carcinogenesis of some CRC. However, contrary to what has been observed in head and neck squamous cell cancer and cancer of the uterine cervix, p16^INK4A does not seem to be a surrogate marker for an active HPV infection in CRC. Therefore, further functional analyses are necessary to elucidate the role of HPV in CRC.

Frequency of human papillomavirus infection in oesophageal squamous cell carcinoma in Iranian patients

Human papillomavirus (HPV) is 1 of the possible aetiological factors in the development of oesophageal squamous cell carcinoma (ESCC). We aimed to study the role of HPV in ESCC. 140 cases of ESCC were analysed for the HPV DNA by polymerase chain reaction (PCR) using GP5+/GP6+ primers for L1 open reading frame (ORF) to amplify a 150 bp segment of HPV L1 ORF. This region was subsequently sequenced to identify the type of HPV. Of the 140 patients enrolled to our study 50.7% were female and 49.3% were male, aged between 20 and 81 y. 33 tumour specimens (23.6%) and 12 (8.6%) non-involved tumour margins were HPV positive. From HPV positive tumour cases 36% were positive in tumour margins. The HPV positive cases were 21.7% male and 25.3% female. There is no correlation between presence and types of HPV with patients' gender and age. The frequency of HPV subtypes in tumoural regions was as follows: HPV-16, 60.6%; HPV-18, 30.3%; HPV-33, 6.1%; and HPV-31, 3%. We found only HPV-16 in tumour margins. Our results are consistent with HPV studies conducted in other high-risk areas for ESCC and provided further evidence to support a causal association of HPV infection with ESCC.

Infectious agents and colorectal cancer: a review of Helicobacter pylori, Streptococcus bovis, JC virus, and human papillomavirus

Based on the high volume of bacteria and viruses that the intestine is exposed to and the importance of infectious agents in some gastrointestinal and anogenital cancers, it is not surprising the many studies have evaluated the association between colorectal cancer and infectious agents. This review highlights investigations of four agents in relation to colorectal cancer. Helicobacter pylori, Streptococcus bovis, JC virus, and human papillomavirus have all been evaluated as possible etiologic agents for colorectal cancer. For each of these agents, a review of possible mechanisms for carcinogenesis and epidemiologic evidence is discussed, and future directions for research are proposed.

Evidence for an association of human papillomavirus infection and colorectal cancer

AIM

To investigate the presence of human papillomavirus (HPV) in colorectal carcinomas and the correlation of the viral infection with prognostic factors for the disease outcome.

METHODS

Seventy-two patients with primary colorectal adenocarcinoma were studied. From each patient two tissue samples were collected: one sample of the tumor and one sample of normal colorectal tissue from an area located 15 cm away from the tumor. Samples of colorectal mucosa obtained from 30 individuals without malignant disease were also studied as control group. Tissues were initially analyzed through MY/GP nested polymerase chain reaction (PCR) and through GP5+/GP6+ auto-nested PCR. Specific primer sets targeting the E6/E7 region of the HPVs 6, 11, 16, 18, 31, 33, 45 were used for typing. Direct DNA sequencing was conducted to confirm positive PCR results.

RESULTS

HPV DNA was detected in colorectal specimens of 60 patients with cancer (83.3%), but in none of the tissues from the non-malignant control group (p<0.001). Twenty-three cancer patients had HPV DNA detected in both the tumor and the matched normal tissue, 23 had HPV only in the tumor, and 14 had HPV only in the normal colorectal tissue. HPV16 was the viral type most frequently detected, being present in 41 out of 60 positive cases (68.3%). No correlation between the presence of the virus and specific prognostic predictors for the disease outcome was observed.

CONCLUSION

HPV is present in the colon and rectum of most patients with colorectal adenocarcinoma, suggesting that this virus may be related to the pathogenesis of colorectal cancer.

Analysis of adenocarcinoma of the colon and rectum: detection of human papillomavirus (HPV) DNA by polymerase chain reaction

OBJECTIVE

The aim of the present work was to evaluate the presence of human papillomavirus genotypes in malignant and normal mucosa of the colon and rectum in order to determine if a relationship exists between HPV infection and colon neoplasms.

MATERIALS AND METHODS

Thirty normal colon tissues and 54 sporadic adenocarcinomas were screened for HPV positivity using nested-PCR. Detection of viral types 6, 11, 16, 18, 33, 34 and 51 was performed by the LIS-SSCP (Low Ionic Strength-Single Strand Conformational Polymorphism) procedure.

RESULTS

Significant differences in high risk HPV infection were found between normal samples and adenocarcinomas (P < 0.001). Among the cases, an inverse association between HPV infection and Dukes staging was also found (P = 0.020). Finally, there was no significant association between HPV and some classical clinicopathological features, although a gradient of infection form rectum to cecum was evident.

CONCLUSION

The present study demonstrates that HPV may infect the glandular mucosa of the colon and suggests a possible association between HPV and colorectal cancer.

Colorectal papillomavirus infection in patients with colorectal cancer

PURPOSE

Infection with human papillomaviruses (HPV) is associated with the development of cervical cancer, but whether HPVs have a role in colorectal cancer remains controversial.

EXPERIMENTAL DESIGNS

To determine the relationship between HPV and colorectal cancer, we did a retrospective, controlled study using tumor and tumor-adjacent colorectal tissues dissected from patients with colorectal cancer, as well as colorectal tissues from control individuals with no cancer. The samples were processed in a blinded fashion for nested PCR and in situ PCR detection of HPV DNAs. The PCR products were gel-purified and sequenced for HPV genotyping.

RESULTS

We found that colorectal tissues from 28 of 55 (51%) patients with colorectal cancer were positive for HPV DNA. Colorectal tissues from all 10 control individuals were negative for HPV DNA (P = 0.0034). Of the 107 usable (GAPDH(+)) samples collected as paired colorectal tissues (tumor and tumor-adjacent tissues) from the patients, 38 (36%) had HPV16 (n = 31), HPV18 (n = 5), or HPV45 (n = 2), with HPV DNA in both tumor and tumor-adjacent tissues of 10 paired samples, 13 in only the tumor, and 5 in only tumor-adjacent tissues. In situ PCR detection of the tumor tissues confirmed the presence of HPV DNA in tumor cells.

CONCLUSION

Our results suggest that colorectal HPV infection is common in patients with colorectal cancer, albeit at a low DNA copy number, with HPV16 being the most prevalent type. HPV infection may play a role in colorectal carcinogenesis.

Human papillomavirus-associated digital squamous cell carcinoma: literature review and report of 21 new cases

OBJECTIVE

Our aim was to review the clinical behavior of human papillomavirus (HPV)-associated digital squamous cell carcinoma (SCC). Specifically, we examined evidence for the tumor's (1) infectious origin and spread, (2) response to therapy, and (3) prognosis and metastatic risk.

DESIGN

We reviewed and performed data tabulation of all 51 reported cases in the English-language literature and a case series of 23 cases (21 of them not previously reported). We present 2 of the cases in depth.

SETTING

We used previously reported cases from MEDLINE and a case series from a single dermatologic operation practice from 1985 to 1999.

RESULTS

(1) Of all cases, 10% (7/72) had an antecedent genital dysplasia or carcinoma containing the same HPV subtype as the digital SCC. (2) The rate of recurrence after general surgical therapy was 43% (6/14). After Mohs micrographic surgery the recurrence rate was 13% (2/16) for the cases in the literature, and 26% (6/23) for our case series. (3) Of tumors, 3% (2/72) have been observed to metastasize.

CONCLUSIONS

(1) This suggests the possibility of genital-digital spread as a mechanism of tumor genesis. (2) HPV-associated digital SCC is more likely to recur after surgical treatment than previously reported. This rate of recurrence greatly exceeds that for cutaneous SCCs in general and may be caused by residual postsurgical HPV. (3) The rate of metastasis, however, appears to be low.

Squamous papilloma of the esophagus: long-term follow up

BACKGROUND AND AIM

Squamous papilloma of the esophagus is a rare benign tumor; less than 200 cases have been reported in the literature. The prevalence of endoscopically diagnosed squamous papilloma of the esophagus has been reported in only a very few series, and varies from 0.01 to 0.43%. Clinical relevance and possible association with other pathological conditions, namely if it is a premalignant lesion, remain a matter of debate. The etiology is controversial, although a role of human papilloma virus has been recently proposed. The aim of this study was to try to determine the prevalence, clinical relevance, possible association with other pathological conditions of the upper digestive tract, and possible etiological role of human papilloma virus on our series of squamous esophageal papillomas.

METHODS

Data from a total of 7618 upper gastrointestinal endoscopies consecutively performed in 4 years were obtained. A 4-year follow up was carried out.

RESULTS

Squamous esophageal papilloma was found in nine patients (0.01%). The mean size of polyps was 4 mm and the mean distance from the dental ridge was 25 cm. Only one patient had more than one polyp. Two patients had liver cirrhosis and three had peptic ulcer disease. All squamous esophageal papillomas were removed and tested for human papilloma virus with commercial available kits for in situ hybridization, but none was found positive.

CONCLUSION

Squamous papilloma of the esophagus is an uncommon disease that does not appear to predispose to esophageal cancer. No association was found with human papilloma virus.

Human papillomavirus type 16-associated primary squamous cell carcinoma of the rectum

Primary squamous cell carcinoma (SCC) of the colorectum is an extremely rare malignancy of unknown etiology and pathogenesis. We describe an 87-year-old man with primary SCC of the rectum. Routine histology demonstrated a squamous metaplasia-dysplasia sequence of the rectal mucosa with subsequent malignant transformation. Molecular biologic analysis using polymerase chain reaction (PCR) and in situ hybridization revealed the presence of human papillomavirus type 16 (HPV-16) DNA within metaplastic, dysplastic, and SCC lesions and in tumor-free rectal mucosa. Moreover, nested reverse-transcription PCR showed transcriptional activity of the viral E6/E7 oncogenes in tumor tissue and tumor-free rectal mucosa. By contrast, 4 typical adenocarcinomas of the rectum and their adjacent normal mucosa were found to be negative for HPV by nested PCR. In line with the well-established concept of HPV-associated anogenital carcinogenesis, our results strongly suggest an etiologic role of HPV-16 in the pathogenesis of the metaplasia-dysplasia-SCC sequence in the case described.

Isolated extragenital bowenoid papulosis of the neck

We report a case of extragenital bowenoid papulosis (BP) in a healthy immunocompetent 42-year-old man. The lesions occurred on the anterolateral aspects of the neck and were not associated with genital, oral, or periungual lesions. Lesional skin tested positive with the Digene hybrid capture system cocktail assay that identifies infection with a mixture of high to intermediate oncogenic human papillomavirus (HPV) types, including types 16, 18, 31, 33, 35, 45, 51, 52, and 56. This cocktail assay identifies infection with HPV types typically associated with high-grade squamous intraepithelial lesions and invasive carcinoma. This case represents the sixth case of isolated cutaneous BP occurring a significant distance from the genital region.

An atraumatic method to establish human colon carcinoma in long-term culture

Techniques for creation of colon carcinoma epithelial cells lines in long-term culture have been available for years, but these techniques have involved mechanical or enzymatic methods to separate epithelial cells from surrounding tissues. While this practice has been intermittently successful, the effect of these traumatic methods on long-term cellular behavior is unknown. Samples of colon carcinoma from patient volunteers were subjected to serial nonenzymatic disruptions of carcinoma cells from surrounding fibrous tissues. Cells were collected, allowed to proliferate, and then tested for their epithelial characteristics (mucin, vimentin, cytokeratin, colon-specific antigen, carcinoembryonic antigen) by immunohistochemistry and flow cytometry. Growth characteristics were determined by phase-contrast microscopy, multiple passage, and freeze/thaw effects. Tumorigenicity was proven in nude mice. Of 11 initial attempts, three resulted in stable long-term culture lines of cells which are demonstrated to behave similarly to the original tumors from which they were derived. This technique adds another reliable in vitro tool for the study of colon carcinoma.

Correlation between HPV types associated with oral squamous cell carcinoma and cervicovaginal cytology: An in situ hybridization study

Epidemiologic and clinical evidence suggests a possible relationship between the human papillomavirus types found in oral squamous cell carcinoma and cervicovaginal cancer. To try to address this question, we analyzed by in situ hybridization 50 paraffin-embedded biopsies of oral squamous cell carcinomas and their corresponding Papanicolaou smears using nonradioactive DNA probes for human papillomavirus type 6/11 and 16/18. This analysis revealed that 70% (35 of 50) of oral squamous cell carcinomas and 56% (28 of 50) of Papanicolaou smears were positive for one or both of these human papillomavirus DNA probes. In 23 of the 28 patients who were positive for human papillomavirus sequences in the cervicovaginal tract, we found the same human papillomavirus type in the oral cavity. Five of the positive in situ hybridization Papanicolaou smears were associated with negative in situ hybridization oral squamous cell carcinomas. Our data suggest that after a primary infection by human papillomavirus, other mucosal sites may eventually become infected. Local environmental factors may contribute to the pathogenesis of lesions such as oral squamous cell carcinoma.

Detection of human papillomavirus DNA in colorectal carcinomas by polymerase chain reaction

Human papillomaviruses (HPVs) are associated with a number of benign and malignant neoplasms. To substantiate the relationship between HPV DNA and colorectal carcinomas, 70 carcinomas and 37 adenomas were analysed in this study. Specific types of HPV DNA in colorectal tumours were detected by polymerase chain reaction (PCR) and Southern blot hybridisation. HPV DNA was detected in 11 of 37 (29.7%) adenomas and in 52.9% 37 of 70 (52.9%) of carcinomas. The expression of HPV DNA in adenomas and carcinomas, especially that of HPV 16 in HPV positive cases (4 of 11 v 26 of 37), was significantly different (p < 0.05). There was no correlation, however, between HPV and the location, differentiation, stage, or survival of malignant neoplasms. These data suggest that HPV DNA, especially type 16, is associated with colorectal carcinogenesis.

Human papillomavirus type 16-positive esophageal papilloma at an endoscopic injection sclerotherapy site

Human papillomavirus infection is important for both the development of papilloma and the progression of the papilloma-carcinoma sequence in the cervix, larynx, lung, and colon. Esophageal squamous cell papilloma is rare but important as a possible precancerous lesion. Esophageal papilloma has previously been thought to develop mainly as a result of chemical irritation by chronic gastroesophageal reflux. However, a few recent studies suggested a role for papillomavirus infection in esophageal tumorigenesis, although the exact route of transmission and invasion of the virus has not been fully elucidated. A case of esophageal squamous papilloma at the site of endoscopic injection sclerotherapy (EIS) for varices is reported. Papilloma development was followed up clinically during a 2-year period, and the papilloma was removed by endoscopic mucosal resection. Histological examination of the tissue confirmed the diagnosis of squamous cell papilloma. DNA analysis of the tumor showed integration of papillomavirus type 16 but not types 18 and 33. The surrounding normal mucosa did not contain any of the three virus types. Injury such as ulceration resulting from EIS may have provided a locus susceptible to the viral infection. The clinical course after EIS should be monitored carefully to detect papilloma formation.

Serum antibody against unfused recombinant E7 protein of human papillomavirus type 16 in cervical cancer patients

Sera were examined for the presence of antibody against E7 protein of human papillomavirus type 16 (HPV-16) by Western blot analysis using the bacterially derived unfused protein. The occurrence rates of anti-E7 antibody against HPV-16 were 14.1% (10/71) in cervical cancer patients, 0% (0/48) in cervical intraepithelial neoplasia patients, and 0% (0/41) in female non-malignant patients. Three patients (one with endometrial cancer, one with breast cancer, and one male patient with colon polyp) out of 115 patients with tumors in organs other than the cervix, had antibody against E7 protein of HPV-16. The serum antibody, once positive, could be detected for a long time after surgical removal of the cancers in all cases that could be followed up. HPV-16 DNA could be detected in 50% (13/26) of cervical cancer patients. Sixty-nine percent (9/13) of patients with HPV-16 DNA in cancers had the antibody and all the patients with stages II, III, and IV cervical cancer (8/8) harboring HPV-16 DNA showed the presence of the antibody against E7 protein of HPV-16. In contrast, only 20% (1/5) of cervical cancer patients with stage Ia or Ib harboring HPV-16 DNA showed positive for the anti-E7 antibody in sera. These findings suggest that the presence of anti-E7 antibody in serum depends on the staging of cervical cancer and extent of HPV infection.

Squamous cell carcinoma of the splenic flexure of the colon: report of a case

A 51-year-old Japanese man underwent resection of a tumor in the splenic flexure of the colon, which proved to be squamous cell carcinoma. At the time of presentation, the liver was found to have multiple metastases. On the 39th postoperative day, the patient died of liver failure. An autopsy demonstrated metastatic nodules on the pleura and parenchyma of both lungs, as well as in the liver, but failed to show any other primary squamous cell carcinoma. We emphasize that a meticulous search to disprove adenosquamous carcinoma is mandatory before a diagnosis of squamous cell carcinoma of the colon can be confirmed.

Confirmation of the association of human papillomavirus with human colon cancer

The human papillomavirus (HPV) has been shown to be associated with neoplasms of the human colon using immunohistochemistry and in situ hybridization. We now report our use of the polymerase chain reaction and Southern blotting to investigate that same association. We selected 38 carcinomas, 21 adenomas, and 24 normal mucosal samples for the current study. Tissue sections were prepared, and then DNA was extracted and subjected to 40 cycles of amplification using Thermus aquaticus DNA polymerase and a set of degenerate primers. Amplified products were analyzed by agarose gel electrophoresis and Southern blotting. The L1 region of the HPV genome was identified in 13 of 38 carcinomas (32%), 8 of 21 adenomas (38%), and 2 of 24 normal biopsy specimens (8%). These observations validate our previous results and confirm the presence of HPV in human colon mucosa and tumors of that mucosa.

Human papillomavirus 16 DNA in NIH3T3 cells transformed by colonic cancer cellular DNA

Human papillomavirus (HPV) 16 DNA is closely associated with human cancers. It has been identified as an aetiological agent in cervical cancers and, recently, in colonic neoplasms. To further understand the role of HPV 16 DNA in colorectal carcinogenesis, NIH3T3 cells were transformed with high molecular weight DNA from colonic cancer cells and the expression of HPV 16 DNA detected. Both human Alu and HPV 16 DNA sequences were found in the type II foci of CC-M2T cells by Southern blot hybridisation. Additionally, 100% tumorigenicity in nude mice was seen. This study shows the transfection of HPV DNA from colonic cancers into NIH3T3 mouse cells and suggests that HPV type 16 might be associated with the malignant transformation of colonic cells.

Investigation of colon cancers for human papillomavirus genomic sequences by polymerase chain reaction

Two previous studies have reported the presence of human papillomavirus (HPV) genomic sequences in colorectal cancers. We examined DNAs from 50 colorectal tumors for HPV sequences by polymerase chain reaction (PCR), using HPV consensus L1 primers for amplification. The PCR products were screened with a generic HPV probe consisting of amplimers of HPV-16 and HPV-18. All tumor DNAs were negative for HPV sequences. These results call into the question the reported association of colorectal cancers with HPVs.

Squamous papilloma of the esophagus associated with the human papillomavirus

Squamous cell papilloma of the esophagus is a rare lesion involving less than 60 case reports worldwide. These lesions are generally asymptomatic but may at times grow and spread rapidly. One fatality, a result of massive dissemination, has been reported. Until recently, human papillomavirus had not been identified in association with esophageal papillomas. A second case, to the authors' knowledge, of esophageal papillomas associated with human papillomavirus is reported. The virus has been previously shown to be associated with abnormal squamous epithelium in and adjacent to esophageal carcinoma. The virus was identified from biopsy specimens obtained at endoscopy using DNA in situ hybridization techniques. The strain of human papillomavirus identified is similar to those found in the oropharynx and genital tract, raising the possibility of sexual transmission. This case also differs from the previous case report involving the human papillomavirus because of the patient's benign clinical course. Our case serves to highlight differences that are perhaps unique to the human papillomavirus. Multiple papillomas found in a proximal location within the esophagus seem to favor involvement of the human papillomavirus. Isolated lesions located distally appear more characteristic of chronic gastroesophageal reflux as an etiology. The syndrome of squamous cell papillomas involving the esophagus is reviewed in the article.