Merkel cell polyomavirus and human papillomavirus infections in cervical disease in Iranian women

Merkel Cell Polyomavirus (MCPyV) and Cancers: Emergency Bell or False Alarm?

Merkel cell polyomavirus (MCPyV), the sole member of Polyomavirus associated with oncogenesis in humans, is the major causative factor of Merkel cell carcinoma (MCC), a rare, neuroendocrine neoplasia of the skin. Many aspects of MCPyV biology and oncogenic mechanisms remain poorly understood. However, it has been established that oncogenic transformation is the outcome of the integration of the viral genome into the host DNA. The high prevalence of MCPyV in the population, along with the detection of the virus in various human tissue samples and the strong association of MCPyV with the emergence of MCC, have prompted researchers to further investigate the role of MCPyV in malignancies other than MCC. MCPyV DNA has been detected in several different non-MCC tumour tissues but with significantly lower prevalence, viral load and protein expression. Moreover, the two hallmarks of MCPyV MCC have rarely been investigated and the studies have produced generally inconsistent results. Therefore, the outcomes of the studies are inadequate and unable to clearly demonstrate a direct correlation between cellular transformation and MCPyV. This review aims to present a comprehensive recapitulation of the available literature regarding the association of MCPyV with oncogenesis (MCC and non-MCC tumours).

Association between human polyomavirus infection and brain cancer: A systematic review and meta-analysis

AIM

The aim of this study was to investigate the prevalence and potential association between the infection with some members of the polyomaviridae family of viruses and development of the brain tumors.

METHODS

A systematic literature search was performed by finding relevant cross-sectional and case-control studies from a large online database. Heterogeneity, OR, and corresponding 95% CI were applied to all studies by meta-analysis and forest plots. The analysis was performed using Stata Software v.14.

RESULTS

Twenty-three articles (33 datasets) were included in the meta-analysis, four (four datasets) of which were case/control studies and the rest were cross-sectional. The pooled prevalence of polyomaviruses among brain cancer patients was 13% (95% CI: 8-20%; I² = 96.91%). In subgroup analysis, the pooled prevalence of JCV, SV40, BKV and Merkel cell polyomavirus was 20%, 8%, 6%, and 16%, respectively. An association was found between polyomavirus infection and brain cancer [summary OR 7.22 (95% CI (2.36-22.05); I² = 0%)]. The subgroup analysis, based on the virus type, demonstrated a strong association between JCV infection and brain cancer development [summary OR 10.34 (95% CI 1.10-97.42; I² = 0%)].

CONCLUSION

The present study showed a significant association between polyomavirus infection and brain tumors. Moreover, these results suggest that polyomavirus infection may be a potential risk factor for the development of brain cancer.

Molecular Investigation of Human Cytomegalovirus and Epstein-Barr virus in Glioblastoma Brain Tumor: A Case-Control Study in Iran

Background

Glioblastoma multiforme is the most invasive and lethal form of brain cancer with unclear etiology. Our study aimed to investigate the molecular prevalence of human cytomegalovirus (HCMV) and Epstein-Barr virus (EBV) infections in patients with glioblastoma multiforme (GBM).

Methods

This case-control study was conducted on 42 FFPE brain tumor samples from GBM patients and 42 brain autopsies from subjects without neurological disorders. The presence of EBV and HCMV DNA was determined, using PCR and nested-PCR assays, respectively.

Results

HCMV DNA was detected in 3 out of 42 (7.1%) of GBM samples and was absent from the control group (p = 0.07). Importantly, EBV DNA was detected in 9 out of 42 (21.4%) brain tissue specimens of GBM subjects, but again in none of the control group (p = 0.001).

Conclusion

Our findings indicate that infection with EBV is associated with GBM.

Reciprocal transactivation of Merkel cell polyomavirus and high-risk human papillomavirus promoter activities and increased expression of their oncoproteins

BACKGROUND

Approximately 15% of human cancers are attributed to viruses. Numerous studies have shown that high-risk human polyomaviruses (HR-HPV) and Merkel cell polyomavirus (MCPyV) are two human tumor viruses associated with anogenetal and oropharyngeal cancers, and with Merkel cell carcinoma, respectively. MCPyV has been found in HR-HPV positive anogenetal and oropharyngeal tumors, suggesting that MCPyV can act as a co-factor in HR-HPV induced oncogenesis. This prompted us to investigate whether the oncoproteins large T-antigen (LT) and small antigen (sT) of MCPyV could affect the transcriptional activity HPV16 and HPV18 and vice versa whether HPV16 and HPV18 E6 and E7 oncoproteins affected the expression of MCPyV LT and sT. Reciprocal stimulation of these viral oncoproteinscould enhance the oncogenic processes triggered by these tumor viruses.

METHODS

Transient co-transfection studies using a luciferase reporter plasmid with the long control region of HPV16 or HPV18, or the early or late promoter of MCPyV and expression plasmids for LT and sT, or E6 and E7, respectively were performed in the HPV-negative cervical cancer cell line C33A, in the keratinocyte cell line HaCaT, and in the oral squamous cell carcinoma cell line HSC-3. Transfections were also performed with deletion mutants of all these promoters and with mutants of all four oncoproteins. Finally, the effect of E6 and E7 on LT and sT expression in the MCPyV-positive Merkel cell carcinoma cell line WaGa and the effect of LT and sT on the expression of E6 and E7 was monitored by Western blotting.

RESULTS

LT and sT stimulated the transcriptional activity of the HPV16 and HPV18 LCR and v.v. E6 and E7 potentiated the MCPyV early and late promoter in all cell lines. Induction by E6 and E7 was p53- and pRb-independent, and transactivation by LT did not require DNA binding, nuclear localization and HSC70/pRb interaction, whereas sT stimulated the HPV16/18 LCR activity in a PP2A- and DnaJ-independent manner.

CONCLUSIONS

These results indicate that the co-infection of MCPyV may act as a co-factor in the initiation and/or progression of HPV-induced cancers.

Prevalence and genotype distribution of human papillomavirus infection in different anatomical sites among men who have sex with men: A systematic review and meta-analysis

Men who have sex with men (MSM) are at increased risk of human papillomavirus (HPV) infection because of their high-risk sexual behaviours. In this study, a meta-analytic approach was used to systematically analyse the literature to elucidate the prevalence and genotype distribution of anal, penile, oral and urethral HPV infection among MSM in the world. To carry out this systematic review, five electronic databases including Web of Science, PubMed, Scopus, Embase, and Google Scholar were searched for relevant studies published from January 2012 to November 2019, and pertinent data were collected from the eligible articles. The pooled HPV prevalence was calculated for each anatomical region using a random-effect model weighted by the inverse variance method. The meta-analysis was performed using the "Metaprop" function in the R package Meta. The overall pooled prevalence of anal, penile, oral and urethral HPV infection among MSM were 78.4% (95% confidence interval [CI]: 75.6%-81.0%), 36.2% (95% CI: 29.1%-44.0%), 17.3% (95% CI: 13.6%-21.7%) and 15.4% (95% CI: 7.8%-27.9%), respectively. Stratified analyses showed that the prevalences of HPV were significantly higher in HIV-positive than HIV-negative MSM. The most frequent HPV high-risk type detected in the anus, penis and oral cavity was HPV-16 (19.9%, 4.9% and 3.1%, respectively). HPV infection is rising in MSM because of high-risk sexual behaviours, suggesting an increased future risk of developing HPV-related diseases and malignancies in this population.

Merkel cell polyomavirus and non-Merkel cell carcinomas: guilty or circumstantial evidence?

Merkel cell polyomavirus (MCPyV) is the major causative factor of the rare but aggressive cancer, Merkel cell carcinoma (MCC). Two characteristics of MCPyV-positive MCCs are integration of the viral genome and expression of a truncated version of one of its oncogenic proteins, namely large T antigen. The strong association of MCPyV with MCC development has incited researchers to further investigate a possible role of this virus in other cancers. However, many of the examples displaying the presence of the virus in the various non-MCC cancers are not able to clearly demonstrate a direct connection between cellular transformation and the presence of the virus. The prevalence of the virus is significantly lower in non-MCC cancers compared to MCCs, with a lower level of viral load and sparse viral protein expression. Moreover, the state of the viral genome, and whether a truncated large T antigen is expressed, has rarely been investigated. Nonetheless, considering the strong oncogenic potential of MCPyV proteins in MCC, the plausible contribution of MCPyV to transformation and cancer growth in non-MCC tumors cannot be ruled out. Furthermore, the absence of MCPyV in cancers does not exclude a hit-and-run mechanism, or the oncoproteins of MCPyV may potentiate the neoplastic process mediated by co-infecting oncoviruses such as high-risk human papillomaviruses and Epstein-Barr virus. The current review is focusing on the available data describing the presence of MCPyV in non-MCC tumors, with an aim to provide a comprehensive overview of the corresponding literature and to discuss the potential contribution of MCPyV to non-MCC cancer in light of this.

Molecular evidence of human papillomaviruses in the retinoblastoma tumor

Retinoblastoma tumor (RB) is one of the most prevalent ocular cancers among children. RB may be caused by inherited mutations in RB1 gene as well as some environmental risk factors. Human papillomaviruses (HPV) are suspected as a risk factor of RB due to their pRb inactivating protein. This study evaluated the molecular prevalence of HPV among the RB tumor specimens in Iran. The RB tumor samples were tested for detection of HPV-L1 gene using a nested-PCR approach, and then followed by sequencing and phylogenetic analysis to reveal HPV types. Overall, there were 61 RB tumor samples; 54/61 (88.5%) had unilateral and 7/61 (11.5%) bilateral RB; 55/61 cases (90.2%) had sporadic non-familial RB tumor. HPV-DNA was detected in 6/61 (9.8%) of patients' tumors; the HPV positive RB cases all had unilateral and unfamiliar sporadic RB tumor. HPV type 16 was the most prevalent type identified across the RB tumor samples (3/61, 4.9%). The rate of detected HPV among the RB specimens seems to be considerable. Further investigations are required to elucidate the exact association between HPV and progression to RB.

Epstein-Barr virus and risk of breast cancer: a systematic review and meta-analysis

Despite the numerous publications regarding the role of Epstein-Barr virus (EBV) in breast cancer development, the topic has still remained controversial. The aim of the meta-analysis was to estimate the overall prevalence of EBV in the breast cancer population, and to investigate the association between EBV and breast cancer risk. The overall prevalence of EBV was calculated 26.37% (95% CI: 22-31%) from the 44 included studies. Meta-analysis of 30 case-control studies showed that the pooled association between EBV and risk of breast cancer is odds ratio 4.74 (95% CI: 2.92-7.69; Z = 6.30; p < 0.0001). Our analyses indicate a strong statistical relationship between EBV infection and risk of breast cancer, suggesting a potential role of EBV infection in the development of breast cancer.

Human papilloma virus infection and fascin over-expression in squamous cell carcinoma of the cervix

Background: Human papilloma virus (HPV) is involved in development of almost all cervical cancers, mainly through the subversion of cellular mechanisms of growth control. Fascin plays central role in subsequent cell transformation events. Fascin mediates stabilization of parallel actin bundles where cellular protrusions are formed; this represents primary stages of cell migration and metastasis. Immunohistochemical assays have shown up-regulation of fascin expression in many epithelial and non-epithelial neoplasms. Therefore, the aim of this study was to investigate HPV infection and fascin expression in samples of cervical cancer.

Methods: Of 66 patients with confirmed SCC, formalin-fixed specimens, embedded in paraffin blocks were evaluated for HPV infection with nested multiplex polymerase chain reaction (NM-PCR) and for fascin expression with immunohistochemical assays. Statistical analysis was performed using Wilcoxon rank-sum test and SPSS software. A p<0.05 was considered for statistical significance.

Results: Of 66 samples, 52 (78.7%) were found positive for HPV infection and fascin over-expression was shown in all squamous cell carcinoma samples.

Conclusion: This study showed fascin overexpression in squamous cell carcinoma of the cervix which might be involved in metastasis of cancers induced by some types of HPV, hypothetically through attenuation of inter-cellular adhesions, and induction of cell motility

Association between human papillomavirus infection and prostate cancer: A global systematic review and meta-analysis

Although an increasing number of studies have been conducted to evaluate the association between human papillomavirus (HPV) infections and distribution of HPV types worldwide with the risk of prostate cancer (PC), the results remain inadequate. Hence, we investigated the association between HPV infection and PC risk using a meta-analysis. Relevant studies from January 1990 to December 2016 were searched in PubMed, Web of sciences, and Scopus databases. Pooled odds ratio (OR) and their corresponding 95% confidence interval (CI) were calculated to find the association between the prevalence of HPV and prostate cancer risk. To do so, data from 24 studies with 5546 prostate cancer cases were pooled in order to evaluate the heterogeneity of chief parameters including study region, specimen type, HPV DNA source, detection technique, publication calendar period, and Gleason score. All statistical analyses were performed using STATA 11 and MedCalc 13. A significant positive association was found between HPV infection and PC risk (OR = 1.281; P = 0.026). The genotype 16 was more frequently found in patients with PC which significantly increased the cancer risk (OR = 1.60; P < 0.001). Age 65 and older could significantly escalate PC risk (OR = 3.564; P < 0.001). Our results clearly favor the potential pathogenetic link between HPV infection and increased risk of PC affirming that HPV infections could play a part in the risk of PC.

Molecular survey on Merkel cell polyomavirus in patients with colorectal cancer

Background: Merkel cell polyomavirus (MCV) has been associated with Merkel cell carcinoma (MCC) in humans, and its role in other human cancers is under investigation. The aim of this study was to investigate MCV genome infection in patients with colorectal cancer (CRC).Methods: This retrospective, case-control study used archived formalin-fixed, paraffin-embedded (FFPE) tissue samples from colorectal cancer patients (cases) and matched healthy subjects (controls) diagnosed by an expert pathologist from hospitals affiliated with Iran University of Medical Sciences, Tehran, Iran from 2011 to 2016. After DNA extraction with a QIAamp® DNA FFPE Tissue Kit, real-time polymerase chain reaction (PCR) was used for diagnosis. A positive control was produced by cloning with the Generay Biotechnology system. SPSS v.22 was used for analysis of demographic variables.Results: There were 157 participants included in the study: 66 were cases and 91 were controls. Their mean ages (±SD) were 59.35±14.48 and 57.21±14.66, respectively. The proportion of males was 57.6% in the case group and 57.1% in the control group. None of the samples were positive for MCV expression by real-time PCR assay. Association was detected between males with CRC and tumor location in the rectum and between males with CRC and the mucinous tumor type.Conclusion: None of the tissues from the CRC or non-cancerous control groups were positive for MCV genome infection, although a low viral load, the sample type, or the method of use should not be neglected. Further studies are recommended to obtain more comprehensive results.

Human Papillomavirus Type 16 Integration Analysis by Real-time PCR Assay in Associated Cancers

Human papillomavirus (HPV) is a common viral infection worldwide associated with a variety of cancers. The integration of the HPV genome in these patients causes chromosomal instability and triggers carcinogenesis. The aim of this study was to investigate the HPV-16 genome physical status in four major cancers related to HPV infection. Formalin-fixed paraffin-embedded blocks from our previous projects on head and neck, colorectal, penile, and cervical cancers were collected, and HPV-16–positive specimens were used for further analysis. The DNA extraction copy number of E2 and E7 genes was calculated by qualitative real-time PCR method. Serially diluted standards that were cloned in PUC57 plasmid were used. Standard curve and melting curve analysis was used for quantification. Of the 672 specimens studied, 76 (11.3%) were HPV-16 positive. We found that 35.6% (16/45) were integrated. Statistical analysis showed that there were significant correlations between integration of HPV-16 and cervical cancer end-stage carcinogenesis (P < .0001), episomal form, and ASCUS lesions (P = .045). Significant correlation in penile cancer patients was seen between the episomal form and high-grade cancer stage (P = .037). Integration is a major factor in the carcinogenesis mechanism of HPV and has different prevalence in various cancers with a higher rate in progression except in penile cancer.

Molecular prevalence of human papillomavirus infection among Iranian women with breast cancer

BACKGROUND

The etiology and molecular mechanisms involved in the development of breast cancer still remain poorly understood. Some epidemiological studies have shown an association between human papillomavirus (HPV) and breast cancer. However, the findings are controversial.

OBJECTIVE

Our study was aimed to investigate the presence of HPV DNA in breast carcinomas of Iranian women.

METHODS

In total, 72 samples of formalin-fixed paraffin-embedded (FFPE) tissues of breast cancer collected between December 2014 and April 2016 were examined. HPV DNA detection was performed by nested-PCR assay. Next, positive samples were subjected to genotyping by the CLART HPV2 microarray system. All statistical analysis was carried out using SPSS v.18.0.

RESULTS

HPV DNA was detected in 4/72 (5.55%) samples. Clinical factors were not statistically associated with HPV presence. However, CLART HPV2 microarray assay failed to determine the genotype of any positive samples.

CONCLUSION

The low frequency of HPV detected in our study does not support an association between breast carcinoma and HPV infection. However, it is possible that HPV may be responsible for breast carcinogenesis only in small percentage of all breast cancer.

Low viral load of Merkel cell polyomavirus in Iranian patients with head and neck squamous cell carcinoma: Is it clinically important?

Recent studies show that the human Merkel cell polyomavirus (MCPyV) may be involved in causing cancer. The objective of this study was to assess the impact of MCPyV on the development of head and neck squamous cell carcinoma (HNSCC). In total, 50 paraffin-embedded HNSCC biopsy samples and 50 adjacent non-cancerous samples were evaluated for the presence of MCPyV DNA and RNA. Among patients, the five most frequent histopathologic sites were the tongue (22.0%), lip (16.0%), submandibular (14.0%), cheek (14.0%), and throat (14.0%). MCPyV DNA was positive in eight (16.0%) samples. The median MCPyV LT-Ag copy number in the eight positive samples and in one non-cancerous sample was 4.8 × 10^-3 and 2.6 × 10^-5  copies/cell, respectively. Quantification of MCPyV LT-Ag revealed increased expression in stage III (5.6 × 10^-3  copies/cell) than in the other stages. The MCPyV DNA load in different stages of HNSCC was also statistically significant (P = 0.027). The viral load was low, suggesting that only a fraction of cancerous cells is infected. This result provides evidence confirming the presence of MCPyV in a subset of Iranian patients with HNSCCs, but further studies needed to confirm our findings.

Human Papillomavirus Investigation in Head and Neck Squamous Cell Carcinoma: Initial Report from the Low Risk HPV Types Associations

Background:

Head and neck squamous cell carcinomas (HNSCC) are a major health issue in many parts of the world. Recently, attention has focused on the human papilloma virus (HPV) as a potential causative agent for HNSCC. This study aimed to survey HPV occurrence in HNSCCs as part of a comprehensive molecular epidemiology approach.

Methods:

In this retrospective study, patients were recruited from hospitals affiliated to the Iran University of Medical Sciences, Tehran, Iran. Formalin-fixed paraffin-embedded (FFPE) blocks were subjected to DNA isolation by QIAamp® DNA FFPE Tissue Kit and nested PCR, HPV-16 specific conventional PCR, and extra INNO-LiPA HPV genotyping assays were subsequently performed. PCR products were purified with a High Pure PCR Product Purification Kit and sequenced with an ABI 3730 XL sequencer. CLC Main Workbench 5 and MEGA5 bioinformatics software was used to analyze the raw data and to create the phylogenetic tree. SPSS v.20 was applied for statistical analysis.

Results:

A total of 156 FFPE blocks were collected from 2011 to 2017. Total mean age (y) of participants was 60.5 ± 12.6; 77.6 % (121/156) being men and 22.4% (35/156) e women. Overall, 5/156 (3.2%) patients (3 females and 2 males) were found to be HPV positive using the three methods. HPV genotyping revealed HPV types 16, 2, 27, and 43 in these malignancies. Tumor location and lymph node involvement indicated significant differences between the sexes.

Conclusion:

Although high risk HPV genotypes have been associated with HNSCCs, our findings indicate a potential of low risk HPV types to also contribute to such malignancies.

Evaluation of Merkel cell polyomavirus in non-small cell lung cancer and adjacent normal cells

Several risk factors have been linked to lung cancer (LC). Nevertheless, a viral etiology has been mentioned for a subset of patients developing LC. The aim of this study was to evaluate the effect of Merkel cell polyomavirus (MCPyV) on developing non-small cell lung cancer (NSCLCs). In total, 96 paraffin-embedded NSCLC biopsies and 96 adjacent non-LC normal specimens were analyzed by quantitative real-time polymerase chain reaction (PCR) for the existence of the MCPyV DNA and the expressions of RNA transcripts. Among the 96 enrolled participants, 42 patients were adenocarcinomas (ADs) and 54 patients were squamous cell carcinoma (SCC). Of the 42 ADs, MCPyV DNA was determined in 15 (35.7%) samples and of the 54 SCC, MCPyV DNA was detected in 22 (40.7%) samples. Only one non-cancerous sample in SCC subjects was positive for MCPyV LT-Ag DNA load (0.216 × 10^-3). In MCPyV-positive subjects, the median MCPyV copy number was higher in the patients with ADs (0.016 × 10^-3 copies/cell) compared to SCCs (0.005 × 10^-3 copies/cell); but this difference was not statistically significant (P = 0.913). In the seven stages of LC, the MCPyV LT-Ag was quantified in stage IV (0.204 × 10^-3 copies/cell) more than in other stages. There was statistically significant difference between stages of cancer and MCPyV LT-Ag DNA load (P = 0.002). These results revealed for the first time the presence of MCPyV in a subset of patients with NSCLCs in Iran. Further studies should be carried out to clarify the role of MCPyV in lung carcinogenesis.

Cloning and Expression of L1 Protein Human Papillomavirus Type 31 Isolated from Iranian Patients in Escherichia coli

Human papillomavirus (HPV), a major pathogen of human cervical cancer, contains a full-length L1 gene encoding its surface capsid protein. One group of potential vaccine candidates against this virus in Iranian patients is based on surface protein components such as HPV31 L1 protein that can make virus-like particles (VLPs). The high immunity response stimulation of this effecter VLP was observed in host, suggesting that the individual characteristics of a particular effecter may require empirical testing for vaccination. In the present study, we decided to clone and express HPV31 L1 protein to investigate its use as a subunit vaccine and furthermore to insert the gene into an Escherichia coli background so as to analyze production of this recombinant protein. We report the presentation of HPV31 in 100 cervical lesion tissue samples based on polymerase chain reaction (PCR). Type of lesion, age, and other characteristics were reviewed and confirmed by a pathologist. The sequence from L1 genes of HPV was selected using special primers. The gene encoding the major capsid protein L1 was used for subcloning in pTG19-T and pET-32a plasmid. The recombinant protein expression was confirmed by RT-PCR using L1 primers and detected by absorption sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblot testing. The results presented here offer new insights into the in vivo response of HPV31 in Iranian patients and European models. On the other hand, the use of recombinant L1 protein for Iranian patient protection as well as vaccination studies will permit testing of this antigen protection rate and open the way to the discovery of protein biomarkers for monitoring clinical and subclinical cervical cancers.

Phylogenetic and structural analysis of merkel cell polyomavirus VP1 in Brazilian samples

Our understanding of the phylogenetic and structural characteristics of the Merkel Cell Polyomavirus (MCPyV) is increasing but still scarce, especially in samples originating from South America. In order to investigate the properties of MCPyV circulating in the continent in more detail, MCPyV Viral Protein 1 (VP1) sequences from five basal cell carcinoma (BCC) and four saliva samples from Brazilian individuals were evaluated from the phylogenetic and structural standpoint, along with all complete MCPyV VP1 sequences available at Genbank database so far. The VP1 phylogenetic analysis confirmed the previously reported pattern of geographic distribution of MCPyV genotypes and the complexity of the South-American clade. The nine Brazilian samples were equally distributed in the South-American (3 saliva samples); North American/European (2 BCC and 1 saliva sample); and in the African clades (3 BCC). The classification of mutations according to the functional regions of VP1 protein revealed a differentiated pattern for South-American sequences, with higher number of mutations on the neutralizing epitope loops and lower on the region of C-terminus, responsible for capsid formation, when compared to other continents. In conclusion, the phylogenetic analysis showed that the distribution of Brazilian VP1 sequences agrees with the ethnic composition of the country, indicating that VP1 can be successfully used for MCPyV phylogenetic studies. Finally, the structural analysis suggests that some mutations could have impact on the protein folding, membrane binding or antibody escape, and therefore they should be further studied.

Detection of four human polyomaviruses (MCPyV, HPyV6, HPyV7 and TSPyV) in cervical specimens from HIV-infected and HIV-uninfected women

OBJECTIVES

To investigate the presence of recently discovered human polyomaviruses in cervical specimens collected from African and French women, in relation to HIV serostatus, high-risk human papillomavirus infection (HR-HPV) and cervical disease.

METHODS

Cervical specimens were collected from 140 HIV-1-seropositive African women and 50 HIV-seronegative French women. Presence of Merkel cell polyomavirus (MCPyV), human polyomavirus 6 (HPyV6), human polyomavirus 7 (HPyV7) and trichodysplasia spinulosa-associated polyomavirus (TSPyV) was detected by real-time PCR, and presence of HR-HPV DNA by Hybrid Capture 2 assay with subsequent HPV genotyping using the INNO-LiPA HPV Genotyping Extra assay. Cervical biopsies were analysed by histopathology.

RESULTS

The detection rates were 55.3%, 3.2%, 2.1% and 0% for MCPyV, HPyV6, HPyV7 and TSPyV, respectively, with no significant difference by population. The MCPyV viral load ranged from 14 to 210 DNA copies/10⁶ cells (median, 80 DNA copies/10⁶ cells), with no difference between women with and without cervical precancerous lesions. There was no association between detection of human polyomaviruses in cervical specimens and geographical origin/HIV serostatus, HR-HPV coinfection or precancerous cervical lesions.

CONCLUSIONS

These observations argue against a possible role of MCPyV as a cofactor in HPV-induced carcinogenesis. MCPyV and, to a lesser extent, HPyV6 and HPyV7 might belong to the female genital tract microbiota.

Detection of Merkel Cell Polyomavirus and Human Papillomavirus in Esophageal Squamous Cell Carcinomas and Non-Cancerous Esophageal Samples in Northern Iran

Human papillomavirus (HPV) infection is one of the hypothesized causes of esophageal squamous cell carcinoma (ESCC), but the etiological association remains uncertain. It was postulated that other infectious agents together with HPV may increase the risk of ESCC. The current investigation aimed to explore the presence of a new human tumor virus, Merkel cell polyomavirus (MCPyV), together with HPV in ESCC tumors and non-cancerous esophageal samples in northern Iran. In total, 96 esophageal samples (51 with ESCC, and 45 without esophageal malignancy) were examined. HPV DNA was detected in esophageal specimens of 16 out of the 51 ESCC cases (31.4 %) and 20 out of the 45 non-cancerous samples (44.4 %). Untypable HPV genotypes were recognized in high rates in cancerous (75.0 %) and non-cancerous (55.0 %) esophageal specimens. MCPyV DNA was detected in esophageal specimens of 23 out of the 51 ESCC cases (45.1 %) and 16 out of the 45 non-cancerous samples (35.6 %). The mean MCPyV DNA copy number was 1.0 × 10(-5) ± 2.4 × 10(-5) and 6.0 × 10(-6) ± 1.3 × 10(-5) per cell in ESCC cases and non-cancerous samples, respectively. There was no statistically significant difference between cancerous and non-cancerous samples regarding mean MCPyV DNA load (P = 0.353). A bayesian logistic regression model adjusted to the location of esophageal specimen and MCPyV infection, revealed a significant association between HPV and odds of ESCC (OR, 2.45; 95 % CI: 1.01-6.16). This study provides the evidence of the detection of the MCPyV DNA at a low viral copy number in cancerous and non- cancerous esophageal samples.

Merkel Cell Carcinoma with a Suppressor of Fused (SUFU) Mutation: Case Report and Potential Therapeutic Implications

Introduction

Merkel cell carcinoma is a neuroendocrine malignancy. Suppressor of fused (SUFU) is a tumor suppressor oncogene that participates in the Hedgehog (Hh) signaling pathway. The aim of the study was to describe a patient whose Merkel cell carcinoma demonstrated a SUFU genomic alteration.

Case Study

The Hh signaling pathway is involved in the pathogenesis of several tumors, including nevoid basal cell carcinoma syndrome that is associated with an alteration of the patched-1 (PTCH1) gene. Targeted molecular therapy against smoothened (SMO) with vismodegib has been shown to be an effective therapeutic intervention for patients with PTCH-1 mutation. The reported patient was presented with metastatic Merkel cell carcinoma. Analysis of his tumor, using a next-generation sequencing-based assay, demonstrated a genomic aberration of SUFU protein, a component of the Hh signaling pathway that acts downstream to SMO and, therefore, is unlikely to be responsive to vismodegib. Of interest, arsenic trioxide or bromo and extra C-terminal inhibitors impact signals downstream to SUFU, making this aberration conceivably druggable. His tumor has initially been managed with chemotherapy (carboplatin and etoposide) and subsequent radiation therapy is planned.

Conclusion

The pathogenesis of Merkel cell carcinoma is multifactorial, and related to ultraviolet radiation exposure, immunosuppression, and Merkel cell polyomavirus. We report a patient with a mutation in SUFU, a potentially actionable component of the Hh signaling pathway.

Electronic supplementary material

The online version of this article (doi:10.1007/s13555-015-0074-5) contains supplementary material, which is available to authorized users.