Biology of human papillomaviruses

B7H4 Role in Solid Cancers: A Review of the Literature

Anti-cancer immunotherapies entirely changed the therapeutic approach to oncological patients. However, despite the undeniable success of anti-PD-1, PD-L1, and CTLA-4 antibody treatments, their effectiveness is limited either by certain types of malignancies or by the arising problem of cancer resistance. B7H4 (aliases B7x, B7H4, B7S1, VTCN1) is a member of a B7 immune checkpoint family with a distinct expression pattern from classical immune checkpoint pathways. The growing amount of research results seem to support the thesis that B7H4 might be a very potent therapeutic target. B7H4 was demonstrated to promote tumour progression in immune "cold" tumours by promoting migration, proliferation of tumour cells, and cancer stem cell persistence. B7H4 suppresses T cell effector functions, including inflammatory cytokine production, cytolytic activity, proliferation of T cells, and promoting the polarisation of naïve CD4 T cells into induced Tregs. This review aimed to summarise the available information about B7H4, focusing in particular on clinical implications, immunological mechanisms, potential strategies for malignancy treatment, and ongoing clinical trials.

Surveillance of human papillomavirus through salivary diagnostics - A roadmap to early detection of oropharyngeal cancer in men

Human papillomavirus (HPV) is the most common sexually transmitted disease. Certain strains have the potential to cause malignancy in multiple anatomical sites if not cleared by the immune system. In most infected people, HPV is cleared within two years. However, HPV may persist in susceptible individuals with certain risk factors, eventually leading to malignancy. New evidence suggests that over 75% of all oropharyngeal cancers (OPC) are directly attributable to HPV. It is estimated that prophylactic HPV vaccination alone may take at least 25 years to have a significant impact on reducing the incidence of OPC. The temporal link between detection of oral HPV, persistence of the infection and the subsequent development of OPC have been well established. Moreover, men have threefold higher risk than women for acquiring HPV-OPC. This comprehensive review focuses on OPC development in men, highlighting the risk factors associated with malignant transformation of HPV-OPC. Current evidence is insufficient to determine whether early identification of at-risk demographics, screening, and prompt diagnosis result in improved outcomes. Hitherto, the effectiveness of an oral HPV screening program in this regard has not been investigated. Nevertheless, the potential to emulate the success of the cervical screening program remains a very real possibility.

CUL4A silencing attenuates cervical carcinogenesis and improves Cisplatin sensitivity

CUL4A is an ubiquitin ligase deregulated in numerous pathologies including cancer and even hijacked by viruses for facilitating their survival and propagation. However, its role in Human papilloma virus (HPV)-mediated cervical carcinogenesis remains elusive. The UALCAN and GEPIA datasets were analyzed to ascertain the transcript levels of CUL4A in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) patients. Subsequently, various biochemical assays were employed to explore the functional contribution of CUL4A in cervical carcinogenesis and to shed some light on its involvement in Cisplatin resistance in cervical cancer. Our UALCAN and GEPIA datasets analyses reveal elevated CUL4A transcript levels in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) patients that correlate with adverse clinicopathological parameters such as tumor stage and lymph node metastasis. Kaplan-Meier plot and GEPIA assessment depict poor prognosis of CESC patients having high CUL4A expression. Varied biochemical assays illustrate that CUL4A inhibition severely curtails hallmark malignant properties such as cellular proliferation, migration, and invasion of cervical cancer cells. We also show that CUL4A knockdown in HeLa cells causes increased susceptibility and better apoptotic induction toward Cisplatin, a mainstay drug used in cervical cancer treatment. More interestingly, we find reversion of Cisplatin-resistant phenotype of HeLa cells and an augmented cytotoxicity towards the platinum compound upon CUL4A downregulation. Taken together, our study underscores CUL4A as a cervical cancer oncogene and illustrates its potential as a prognosis indicator. Our investigation provides a novel avenue in improving current anti-cervical cancer therapy and overcoming the bottle-neck of Cisplatin resistance.

The Hallmarks of Cervical Cancer: Molecular Mechanisms Induced by Human Papillomavirus

Human papillomaviruses (HPVs) and, specifically, high-risk HPVs (HR-HPVs) are identified as necessary factors in the development of cancer of the lower genital tract, with CaCU standing out as the most prevalent tumor. This review summarizes ten mechanisms activated by HR-HPVs during cervical carcinogenesis, which are broadly associated with at least seven of the fourteen distinctive physiological capacities of cancer in the newly established model by Hanahan in 2022. These mechanisms involve infection by human papillomavirus, cellular tropism, genetic predisposition to uterine cervical cancer (CaCU), viral load, viral physical state, regulation of epigenetic mechanisms, loss of function of the E2 protein, deregulated expression of E6/E7 oncogenes, regulation of host cell protein function, and acquisition of the mesenchymal phenotype.

DNA from multiple viral species is associated with Alzheimer's disease risk

INTRODUCTION

Multiple infectious agents, including viruses, bacteria, fungi, and protozoa, have been linked to Alzheimer's disease (AD) risk by independent lines of evidence. We explored this association by comparing the frequencies of viral species identified in a large sample of AD cases and controls.

METHODS

DNA sequence reads that did not align to the human genome in sequences were mapped to viral reference sequences, quantified, and then were tested for association with AD in whole exome sequences (WES) and whole genome sequences (WGS) datasets.

RESULTS

Several viruses were significant predictors of AD according to the machine learning classifiers. Subsequent regression analyses showed that herpes simplex type 1 (HSV-1) (odds ratio [OR] = 3.71, p = 8.03 × 10-4) and human papillomavirus 71 (HPV-71; OR = 3.56, p = 0.02), were significantly associated with AD after Bonferroni correction. The phylogenetic-related cluster of Herpesviridae was significantly associated with AD in several strata of the data (p < 0.01).

DISCUSSION

Our results support the hypothesis that viral infection, especially HSV-1, is associated with AD risk.

Exploring the correlation between progression of human papillomavirus infection towards carcinogenesis and nutrition

Human papillomavirus (HPV) is a common sexually transmitted virus that can lead to the development of various types of cancer. While there are vaccines available to prevent HPV infection, there is also growing interest in the role of nutrition in reducing the risk of HPV-related cancers in HPV positive patients. Diet and nutrition play a critical role in maintaining overall health and preventing various diseases. A healthy diet can strengthen the immune system, which is essential for fighting off infections, including HPV infections, and preventing the growth and spread of cancer cells. Therefore, following a healthy diet and maintaining a healthy weight are important components of HPV and cancer prevention. This article explores the current scientific evidence on the relationship between nutrition and HPV, including the impact of specific nutrients, dietary patterns, and supplements on HPV infection toward cancer progression.

Human papillomavirus-associated cancer incidence by disaggregated Asian American, Native Hawaiian, and other Pacific Islander ethnicity

BACKGROUND

Asian Americans and Native Hawaiians and other Pacific Islanders have suboptimal human papillomavirus (HPV) vaccination and cancer screening rates. Asian Americans and NHPIs are often aggregated, masking disparities characterized by varying colonization and immigration patterns and cultural and religious beliefs between populations and ethnicities. We examined the incidence of HPV-associated cancers across disaggregated Asian American and NHPI ethnicities.

METHODS

Using the Surveillance, Epidemiology, and End Results Detailed Asian/Pacific Islander database, we calculated 1990 to 2014 sex-specific, age-standardized HPV-associated cancer incidence of cervical carcinoma, oropharyngeal squamous cell carcinoma (SCC), vulvar SCC, vaginal SCC, anal SCC, and penile SCC by ethnicity: Asian Indian and Pakistani, Chinese, Filipino, Japanese, Kampuchean, Korean, Laotian, Native Hawaiian, other Pacific Islander, and Vietnamese. Trends by calendar period (1990 to 1996, 1997 to 2002, 2003 to 2008, 2009 to 2014) were estimated using Joinpoint regression.

RESULTS

The most common HPV-associated cancer was cervical carcinoma in women and oropharyngeal SCC in men. During 1990 to 2014, cervical carcinoma incidence per 100 000 ranged from 4.5 (Asian Indian and Pakistani) to 20.7 (Laotian). Cervical carcinoma incidence only statistically significantly declined for Asian Indian and Pakistani, Filipino, Korean, Laotian, and Vietnamese women (range = 19.9% to 44.1% decline per period). Among men, oropharyngeal SCC incidence per 100 000 ranged from 1.1 (Chinese) to 5.1 (Native Hawaiian). Oropharyngeal SCC incidence only statistically significantly increased (31.0% increase per period) for Japanese men. Heterogeneity across ethnicities were observed for other cancer sites.

CONCLUSIONS

HPV-associated cancer incidence varied widely between Asian Americans and NHPIs and by ethnicity, underscoring the need for improved data capture of ethnic groups in research and more tailored interventions to better address health disparities between Asian American and NHPI populations.

Human Papilloma Virus-Infected Cells

Human papillomavirus (HPV) is associated with infection of different tissues, such as the cervix, anus, vagina, penis, vulva, oropharynx, throat, tonsils, back of the tongue, skin, the lungs, among other tissues. HPV infection may or may not be associated with the development of cancer, where HPVs not related to cancer are defined as low-risk HPVs and are associated with papillomatosis disease. In contrast, high-risk HPVs (HR-HPVs) are associated with developing cancers in areas that HR-HPV infects, such as the cervix. In general, infection of HPV target cells is regulated by specific molecules and receptors that induce various conformational changes of HPV capsid proteins, allowing activation of HPV endocytosis mechanisms and the arrival of the HPV genome to the human cell nucleus. After the transcription of the HPV genome, the HPV genome duplicates exponentially to lodge in a new HPV capsid, inducing the process of exocytosis of HPV virions and thus releasing a new HPV viral particle with a high potential of infection. This infection process allows the HPV viral life cycle to conclude and enables the growth of HPV virions. Understanding the entire infection process has been a topic that researchers have studied and developed for decades; however, there are many things to still understand about HPV infection. A thorough understanding of these HPV infection processes will allow new potential treatments for HPV-associated cancer and papillomatosis. This chapter focuses on HPV infection, the process that will enable HPV to complete its HPV life cycle, emphasizing the critical role of different molecules in allowing this infection and its completion during the HPV viral life cycle.

Insights into the role of complement regulatory proteins in HPV mediated cervical carcinogenesis

The persistent infection of high-risk Human papillomavirus (HR-HPV) induced cervical cancer remains a challenge in women worldwide including India. Recent advances in cancer research have paved the way for advanced cancer treatment modalities including immunotherapy by manipulating the function or number of cytotoxic T cells. It is well established that anaphylatoxins like C3a and C5a of complement system influence tumor growth by evading apoptosis leading to progression of cancer. The role of the complement system, particularly the complement regulatory proteins (CRPs) which are important determinants of immune response play a crucial role in carcinogenesis. In a tumor microenvironment (TME) assisted suppression of immune effector cells may be achieved through CRPs. However, recent advances in pharmacogenomics including drug designing and combination of these approaches have provided a holistic understanding of signaling pathways and their crosstalk, to regulate cellular communications.This review describes the role of complement system; particularly CRPs in HPV induced cervical carcinogenesis which may be used for designing anti- HPV or cervical cancer therapeutics.

Direct Comparison of HPV16 Viral Genomic Integration, Copy Loss, and Structural Variants in Oropharyngeal and Uterine Cervical Cancers Reveal Distinct Relationships to E2 Disruption and Somatic Alteration

Squamous cell carcinoma of the oropharynx caused by HPV type 16 (HPV16+ OPSCC) is the most common HPV-associated malignancy in the USA and has many molecular differences from uterine cervical squamous cell carcinoma (UCSCC). Our understanding of HPV oncogenesis relied on studies of UCSCC revealing a consensus model reliant on HPV integration with a loss of E2. Here, we compare patterns of HPV integration in UCSCC and OPSCC by analysis of affinity capture sequencing of the HPV16 genome in 104 OPSCC and 44 UCSCC tumors. These cohorts were contemporaneously sequenced using an identical strategy. Integration was identified using discordant read pair clustering and assembly-based approaches. Viral integration sites, structural variants, and copy losses were examined. While large-scale deep losses of HPV16 genes were common in UCSCC and were associated with E2 loss, deep copy losses of the HPV16 genome were infrequent in HPV16+ OPSCC. Similarly, structural variants within HPV16 favored E2 loss in UCSCC but not OPSCC. HPV16 integration sites were non-random, with recurrent integration hot-spots identified. OPSCC tumors had many more integration sites per tumor when compared to UCSCC and had more integration sites in genomic regions with high gene density. These data show that viral integration and E2 disruption are distinct in UCSCC and OPSCC. Our findings also add to growing literature suggesting that HPV tumorigenesis in OPSCC does not follow the model developed based on UCSCC.

Cautious Sexual Attitudes Diminish Intent to Vaccinate Children against HPV in Utah

Although most Human papillomavirus (HPV) infections are mild and are cleared by the immune system, some high-risk HPV strains can cause various cancers. Vaccines have been developed that protect against high-risk HPV strains. HPV vaccines have been approved for use by the CDC (Centers for Disease Control and Prevention) and are recommended for everyone aged 11–26. Despite the availability of safe and effective vaccines, uptake is low. HPV vaccine uptake has been extensively studied on a national and international level, but less is known about vaccine acceptance on a state or local level. The state of Utah, in the United States of America, has a relatively low HPV vaccination rate. In this study, we identified factors that impact the intent of Utah parents to vaccinate their children against HPV. A survey was distributed electronically to Utah residents. Survey results were analyzed using confirmatory factor analysis, structural equation modeling, and univariate analysis. Knowledge about HPV and positive vaccine attitudes had the greatest positive effect on intent to vaccinate children against HPV. Cautious sexual attitudes and high religious practice were found to have a negative impact on intent to vaccinate. Effective public health messaging will consider the cultural and religious influences of the target population.

Effects of Religious Practice and Teachings about Sexual Behavior on Intent to Vaccinate against Human Papillomavirus

Human papillomavirus (HPV) is the most common sexually transmitted infection in the United States. Most infections are mild and clear without treatment in 1 to 2 years. Some HPV strains result in persistent infection, which can cause various cancers, including cervical, penile, anal, mouth, and throat cancers. Vaccines have been developed that provide protection against the highest risk HPV strains. Despite HPV vaccines having been proven to be safe and effective, uptake has been low. Religiosity has been negatively correlated with HPV vaccine uptake in some studies. It is hypothesized that religiosity and Christian religious affiliation could impact parents’ decision to vaccinate their children against HPV via teachings and beliefs about sexual behaviors. A survey was distributed to participants to determine what factors, including religiosity and views about sex, impacted HPV vaccination. The survey results (n = 442) were analyzed using confirmatory factor analysis, structural equation modeling, and univariate factor analysis. The association between religious practice and vaccine attitudes were complex, with religious practice slightly positively correlated with pro-vaccine attitudes and vaccine knowledge, but also with the belief that religious adherence to expectations surrounding sexual behavior will protect children from HPV infection, as well as more negative views towards vaccines, in general.

Raman Spectroscopy of Individual Cervical Exfoliated Cells in Premalignant and Malignant Lesions

Cervical cancer is frequent neoplasia. Currently, the diagnostic approach includes cervical cytology, colposcopy, and histopathology studies; combining detection techniques increases the sensitivity and specificity of the tests. Raman spectroscopy is a high-resolution technique that supports the diagnosis of malignancies. This study aimed to evaluate the Raman spectroscopy technique discriminating between healthy and premalignant/malignant cervical cells. We included 81 exfoliative cytology samples, 29 in the “healthy group” (negative cytology), and 52 in the “CIN group” (premalignant/malignant lesions). We obtained the nucleus and cytoplasm Raman spectra of individual cells. We tested the spectral differences between groups using Permutational Multivariate Analysis of Variance (PERMANOVA) and Canonical Analysis of Principal Coordinates (CAP). We found that Raman spectra have increased intensity in premalignant/malignant cells compared with healthy cells. The characteristic Raman bands corresponded to proteins and nucleic acids, in concordance with the increased replication and translation processes in premalignant/malignant states. We found a classification efficiency of 76.5% and 82.7% for cytoplasmic and nuclear Raman spectra, respectively; cell nucleus Raman spectra showed a sensitivity of 84.6% in identifying cervical anomalies. The classification efficiency and sensitivity obtained for nuclear spectra suggest that Raman spectroscopy could be helpful in the screening and diagnosis of premalignant lesions and cervical cancer.

Nuclear factor erythroid 2-related factor 2 in human papillomavirus-related cancers

High-risk human papillomavirus (HR-HPV) infection is a necessary cause for the development of cervical cancer. Moreover, HR-HPV is also associated with cancers in the anus, vagina, vulva, penis and oropharynx. HR-HPVs target and modify the function of different cell biomolecules, such as glucose, amino acids, lipids and transcription factors (TF), such as p53, nuclear factor erythroid 2-related factor 2 (Nrf2), among others. The latter is a master TF that maintains redox homeostasis. Nrf2 also induces the transcription of genes associated with cell detoxification. Since both processes are critical for cell physiology, Nrf2 deregulation is associated with cancer development. Nrf2 is a crucial molecule in HPV-related cancer development but underexplored. Moreover, Nrf2 activation is also associated with resistance to chemotherapy and radiotherapy in these cancers. This review focusses on the importance of Nrf2 during HPV-related cancer development, resistance to therapy and potential therapies associated with Nrf2 as a molecular target.

Involvement of Felis catus papillomavirus type 2 in the tumorigenesis of feline Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a cutaneous neuroendocrine tumor. We recently demonstrated that cats with MCC often have other proliferative cutaneous lesions, such as squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). Based on this finding, we hypothesize that Felis catus papillomavirus (FcaPV) is involved in the development of MCC in cats, similar to SCC and BCC. To investigate this hypothesis, the presence of FcaPV nucleic acid and immunoreactivity for tumor suppressor proteins were examined in 21 feline MCC cases. Polymerase chain reaction using FcaPV type-specific primers detected FcaPV2 DNA in 20/21 samples of MCC. The complete FcaPV2 sequence was characterized in one case. In situ hybridization for FcaPV2 E7 revealed punctate nuclear signals within tumor cells in 19/21 MCC. Increased immunoreactivity for p16^CDKN2A protein and decreased immunoreactivity for retinoblastoma (pRb) and p53 proteins were observed in 20/21 MCC. These results suggest that feline MCC cases are infected with FcaPV2 and the subsequent inhibition of pRb and p53 induced by integrated viral oncogenes is associated with feline MCC tumorigenesis, similar to other PV-induced proliferative cutaneous lesions. On the other hand, the single case of FcaPV2-negative MCC showed strong p53 immunoreactivity, suggesting mutations in p53 caused by cancer inducers other than FcaPV2 infection in this case. The present study suggests FcaPV2 as a cause of feline MCC.

Pathogens and Carcinogenesis: A Review

Cancer is a global health problem associated with genetics and unhealthy lifestyles. Increasingly, pathogenic infections have also been identified as contributors to human cancer initiation and progression. Most pathogens (bacteria, viruses, fungi, and parasites) associated with human cancers are categorized as Group I human carcinogens by the International Agency for Research on Cancer, IARC. These pathogens cause carcinogenesis via three known mechanisms: persistent infection that cause inflammation and DNA damage, initiation of oncogene expression, and immunosuppression activity of the host. In this review, we discuss the carcinogenesis mechanism of ten pathogens, their implications, and some future considerations for better management of the disease. The pathogens and cancers described are Helicobacter pylori (gastric cancer), Epstein-Barr virus (gastric cancer and lymphoma), Hepatitis B and C viruses (liver cancer), Aspergillus spp. (liver cancer), Opisthorchis viverrine (bile duct cancer), Clonorchis sinensis (bile duct cancer), Fusobacterium nucleatum (colorectal cancer), Schistosoma haematobium (bladder cancer); Human Papillomavirus (cervical cancer), and Kaposi's Sarcoma Herpes Virus (Kaposi's sarcoma).

The Role of circRNAs in Human Papillomavirus (HPV)-Associated Cancers

Circular RNAs (circRNAs) are a new class of "non-coding RNAs" that originate from non-sequential back-splicing of exons and/or introns of precursor messenger RNAs (pre-mRNAs). These molecules are generally produced at low levels in a cell-type-specific manner in mammalian tissues, but due to their circular conformation they are unaffected by the cell mRNA decay machinery. circRNAs can sponge multiple microRNAs or RNA-binding proteins and play a crucial role in the regulation of gene expression and protein translation. Many circRNAs have been shown to be aberrantly expressed in several cancer types, and to sustain specific oncogenic processes. Particularly, in virus-associated malignancies such as human papillomavirus (HPV)-associated anogenital carcinoma and oropharyngeal and oral cancers, circRNAs have been shown to be involved in tumorigenesis and cancer progression, as well as in drug resistance, and some are useful diagnostic and prognostic markers. HPV-derived circRNAs, encompassing the HPV E7 oncogene, have been shown to be expressed and to serve as transcript for synthesis of the E7 oncoprotein, thus reinforcing the virus oncogenic activity in HPV-associated cancers. In this review, we summarize research advances in the biogenesis of cell and viral circRNAs, their features and functions in the pathophysiology of HPV-associated tumors, and their importance as diagnostic, prognostic, and therapeutic targets in anogenital and oropharyngeal and oral cancers.

HIV susceptibility in women: The roles of genital inflammation, sexually transmitted infections and the genital microbiome

Given that heterosexual transmission of HIV across the genital mucosa is the most common route of infection in women, an in-depth understanding of the biological mechanisms associated with HIV risk in the female genital tract (FGT) is essential for effective control of the epidemic. Genital pro-inflammatory cytokines are well-described biological co-factors to HIV risk. Increased levels of pro-inflammatory cytokines in the FGT have been associated with a 3-fold higher-risk of acquiring HIV, presumably through involvement in barrier compromise and the recruitment of highly activated HIV target cells to the site of initial viral infection and replication. Sexually transmitted infections (STIs) and bacterial vaginosis (BV) are suggested possible contributors to genital inflammation in the FGT, and this, coupled with the relationship between genital inflammation and HIV risk, underscores the importance of effective treatment of STI and BV in the promotion of women's health. In most low- and middle-income countries, STIs are treated syndromically, a practice providing rapid treatment without identifying the infection source. However, this approach has been associated with over-diagnosis and the overuse of drugs. Further, because many women with STIs are asymptomatic, syndromic management also fails to treat a vast proportion of infected women. Although several studies have explored the role of STIs and the vaginal microbiome on genital inflammation and HIV risk, the impact of STI and BV management on genital inflammation remains poorly understood. This review aimed to collate the evidence on how BV and STI management efforts affect genital inflammation and the genital microbiome in women.

CRISPR-Cas9: A Preclinical and Clinical Perspective for the Treatment of Human Diseases

At present, the idea of genome modification has revolutionized the modern therapeutic research era. Genome modification studies have traveled a long way from gene modifications in primary cells to genetic modifications in animals. The targeted genetic modification may result in the modulation (i.e., either upregulation or downregulation) of the predefined gene expression. Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated nuclease 9 (Cas9) is a promising genome-editing tool that has therapeutic potential against incurable genetic disorders by modifying their DNA sequences. In comparison with other genome-editing techniques, CRISPR-Cas9 is simple, efficient, and very specific. This enabled CRISPR-Cas9 genome-editing technology to enter into clinical trials against cancer. Besides therapeutic potential, the CRISPR-Cas9 tool can also be applied to generate genetically inhibited animal models for drug discovery and development. This comprehensive review paper discusses the origin of CRISPR-Cas9 systems and their therapeutic potential against various genetic disorders, including cancer, allergy, immunological disorders, Duchenne muscular dystrophy, cardiovascular disorders, neurological disorders, liver-related disorders, cystic fibrosis, blood-related disorders, eye-related disorders, and viral infection. Finally, we discuss the different challenges, safety concerns, and strategies that can be applied to overcome the obstacles during CRISPR-Cas9-mediated therapeutic approaches.

Global gene methylation profiling of common warts caused by human papillomaviruses infection

Infection with the human papillomaviruses (HPV) often involves the epigenetic modification of the host genome. Despite its prevalence among the population, host genome methylation in HPV-induced warts is not clearly understood. In this study, genome-wide methylation profiling was carried out on paired healthy skin and wart samples in order to investigate the effects that benign HPV infection has on gene methylation status. To overcome this gap in knowledge, paired wart (n = 12) and normal skin (n = 12) samples were obtained from Arab males in order to perform DNA extraction and subsequent genome-wide methylation profiling on the Infinium Methylation EPIC Bead Chip microarray. Analysis of differential methylation revealed a clear pattern of discrimination between the wart and normal skin samples. In warts, the most differentially methylated (DM) genes included long non-coding RNAs (AC005884, AL049646.2, AC126121.2, AP001790.1, and AC107959.3), microRNAs (MIR374B, MIR596, MIR1255B1, MIR26B, and MIR196A2),snoRNAs (SNORD114-22, SNORD70, and SNORD114-31), pseudogenes (AC069366.1, RNU4ATAC11P, AC120057.1, NANOGP3, AC106038.2, TPT1P2, SDC4P, PKMP3, and VN2R3P), and protein-coding genes (AREG, GJB2, C12orf71, AC020909.2, S100A8, ZBED2, FABP7, and CYSLTR1). In addition, pathway analysis revealed that, among the most differentially methylated genes, STAT5A, RARA, MEF2D, MAP3K8, and THRA were the common regulators. It can be observed that HPV-induced warts involve a clear and unique epigenetic alteration to the host genome.

Bioinformatics Analysis of Key Genes and Pathways of Cervical Cancer

Background and Objective

Globally, cervical cancer (CC) is the fourth most common cancer affecting women. Although effective screening reduces its incidence, it remains one of the most serious cancers threatening the health of women. Therefore, the purpose of this study is to find new genes that can be used as potential biomarkers for the prognosis of CC.

Methods and Results

After downloading three datasets such as GSE6791, GSE63678, and GSE63514 from the Gene Expression Omnibus (GEO), we combined the expression matrixes and analyzed them to obtain the differential expressed genes (DEGs). Next, using the STRING website, we performed the protein interaction network analysis. Subsequently, hub genes were screened using the R and Cytoscape software. Then, the expression difference and survival analyses of the hub genes were confirmed using GIPIA. Here, we established that the KNTC1 gene was correlated to the overall survival prognosis of CC. Besides, the expression of the KNTC1 gene in the GSE63514 dataset was significantly different from that of the normal cervix, cervical pre-cancerous lesions, and CC. Consequently, immunohistochemistry analysis showed that the results have a definite diagnostic value.

Conclusion

The KNTC1 gene could be linked with the pathophysiology of CC and maybe one of the early diagnostic markers for the diagnosis of cervical pre-cancerous lesions.

Identification of pathways and genes in the process of E6/E7-induced carcinogenesis of esophageal epithelial cells

Human papillomavirus (HPV) infection was associated with some carcinomas, especially malignant tumors in upper digestive tract, upper respiratory tract, and genitourinary system. The mechanism of the viral transformation of normal cells is still not very clear. To investigate the tumorigenesis of epithelial cells, E6/E7-induced malignant transformation model cells were used for expression profiling analysis by performing RNA expression microarray detection. Bioinformatics analysis was applied to investigate the cellular process changes along with the E6/E7 expression in SHEE cells. The differentially expressed genes were further grouped and uploaded for Search Tool for the Retrieval of Interacting Genes analysis. The protein-protein interaction results were visualized. The hub genes and their first-neighbors genes were selected, followed by gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis. The obtained results demonstrated that tumor-related biological processes began to emerge during the carcinogenesis process from 48th passage to 76th passage of SHEE cells after E6/E7 expression. Ten hub genes were identified and analyzed during the E6/E7-induced tumorigenesis. This study explores the gene expression network in the progressive transformation of immortalized esophageal epithelial cells induced by E6/E7 expression. Understanding the biological processes and hub genes that first appear during the transformation will provide some clues to the mechanism of E6/E7-induced carcinogenesis of esophageal epithelial cells.

In Vitro Organotypic Systems to Model Tumor Microenvironment in Human Papillomavirus (HPV)-Related Cancers

Despite the well-known role of chronic human papillomavirus (HPV) infections in causing tumors (i.e., all cervical cancers and other human malignancies from the mucosal squamous epithelia, including anogenital and oropharyngeal cavity), its persistence is not sufficient for cancer development. Other co-factors contribute to the carcinogenesis process. Recently, the critical role of the underlying stroma during the HPV life cycle and HPV-induced disease have been investigated. The tumor stroma is a key component of the tumor microenvironment (TME), which is a specialized entity. The TME is dynamic, interactive, and constantly changing-able to trigger, support, and drive tumor initiation, progression, and metastasis. In previous years, in vitro organotypic raft cultures and in vivo genetically engineered mouse models have provided researchers with important information on the interactions between HPVs and the epithelium. Further development for an in-depth understanding of the interaction between HPV-infected tissue and the surrounding microenvironment is strongly required. In this review, we critically describe the HPV-related cancers modeled in vitro from the simplified 'raft culture' to complex three-dimensional (3D) organotypic models, focusing on HPV-associated cervical cancer disease platforms. In addition, we review the latest knowledge in the field of in vitro culture systems of HPV-associated malignancies of other mucosal squamous epithelia (anogenital and oropharynx), as well as rare cutaneous non-melanoma associated cancer.

From Ancient to Emerging Infections: The Odyssey of Viruses in the Male Genital Tract

The male genital tract (MGT) is the target of a number of viral infections that can have deleterious consequences at the individual, offspring, and population levels. These consequences include infertility, cancers of male organs, transmission to the embryo/fetal development abnormalities, and sexual dissemination of major viral pathogens such as human immunodeficiency virus (HIV) and hepatitis B virus. Lately, two emerging viruses, Zika and Ebola, have additionally revealed that the human MGT can constitute a reservoir for viruses cleared from peripheral circulation by the immune system, leading to their sexual transmission by cured men. This represents a concern for future epidemics and further underlines the need for a better understanding of the interplay between viruses and the MGT. We review here how viruses, from ancient viruses that integrated the germline during evolution through old viruses (e.g., papillomaviruses originating from Neanderthals) and more modern sexually transmitted infections (e.g., simian zoonotic HIV) to emerging viruses (e.g., Ebola and Zika) take advantage of genital tract colonization for horizontal dissemination, viral persistence, vertical transmission, and endogenization. The MGT immune responses to viruses and the impact of these infections are discussed. We summarize the latest data regarding the sources of viruses in semen and the complex role of this body fluid in sexual transmission. Finally, we introduce key animal findings that are relevant for our understanding of viral infection and persistence in the human MGT and suggest future research directions.

Host proteome linked to HPV E7-mediated specific gene hypermethylation in cancer pathways

Background

Human papillomavirus (HPV) infection causes around 90% of cervical cancer cases, and cervical cancer is a leading cause of female mortality worldwide. HPV-derived oncoprotein E7 participates in cervical carcinogenesis by inducing aberrant host DNA methylation. However, the targeting specificity of E7 methylation of host genes is not fully understood but is important in the down-regulation of crucial proteins of the hallmark cancer pathways. In this study, we aim to link E7-driven aberrations in the host proteome to corresponding gene promoter hypermethylation events in the hope of providing novel therapeutic targets and biomarkers to indicate the progression of cervical cancer.

Methods

HEK293 cells were transfected with pcDNA3.1-E7 plasmid and empty vector and subjected to mass spectrometry-based proteomic analysis. Down-regulated proteins (where relative abundance was determined significant by paired T-test) relevant to cancer pathways were selected as gene candidates for mRNA transcript abundance measurement by qPCR and expression compared with that in SiHa cells (HPV type 16 positive). Methylation Specific PCR was used to determine promoter hypermethylation in genes downregulated in both SiHa and transfected HEK293 cell lines. The FunRich and STRING databases were used for identification of potential regulatory transcription factors and the proteins interacting with transcription factor gene candidates, respectively.

Results

Approximately 400 proteins totally were identified in proteomics analysis. The transcripts of six genes involved in the host immune response and cell proliferation (PTMS, C1QBP, BCAP31, CDKN2A, ZMYM6 and HIST1H1D) were down-regulated, corresponding to proteomic results. Methylation assays showed four gene promoters (PTMS, C1QBP, BCAP31 and CDKN2A) were hypermethylated with 61, 55.5, 70 and 78% increased methylation, respectively. Those four genes can be regulated by the GA-binding protein alpha chain, specificity protein 1 and ETS-like protein-1 transcription factors, as identified from FunRich database predictions.

Conclusions

HPV E7 altered the HEK293 proteome, particularly with respect to proteins involved in cell proliferation and host immunity. Down-regulation of these proteins appears to be partly mediated via host DNA methylation. E7 possibly complexes with the transcription factors of its targeting genes and DNMT1, allowing methylation of specific target gene promoters.

E6 and E7 gene polymorphisms in human papillomavirus Type-6 identified in Southwest China

BACKGROUND

Human papillomavirus type-6 (HPV6) is the major etiological agent of anogenital warts both men and women. The present study aimed to characterize the genetic diversity among HPV6 in Southwest China, and to investigate the origin of, selective pressure experienced by, and impact of the resultantly identified genetic variants on the HPV6 secondary structure.

METHODS

Phylogenetic trees were constructed by Maximum-likelihood and the Kimura 2-parameters methods by Molecular Evolutionary Genetics Analysis version 6.0. The diversity of secondary structure was analyzed by PSIPred software. The selection pressures acting on the E6/E7 genes were estimated by Phylogenetic Analyses by Maximum Likelihood version 4.8 software.

RESULTS

HPV6 was the most prevalent low risk HPV type in southwest China. In total, 143 E6 and E7 gene sequences of HPV6 isolated from patients were sequenced and compared to GenBank HPV6 reference sequence X00203. The results of these analyses revealed that both the HPV6 E6 and E7 were highly conserved within the analyzed patient samples, and comprised only 3 types of variant sequence, respectively. Furthermore, the analysis of HPV6 E6 and E7 sequences revealed seven/five single-nucleotide mutations, two/four and five/one of which were non-synonymous and synonymous, respectively. The phylogenetic analyses of the E6 and E7 sequences indicated that they belonged to sub-lineage A1 and sub-lineage B1, whereas the selective pressure analyses showed that only the E7 mutation sites 4R, 34E, and 52F were positive selection.

CONCLUSIONS

HPV6 (detection rate = 13.10%) was very prevalent in southwest China, both the HPV6 E6 and E7 sequences were highly conserved within the analyzed patient samples in southwest China, indicating that the low risk HPV6 can adapt to the environment well without much evolution.

Human Papillomavirus Type 16 Disables the Increased Natural Killer Cells in Early Lesions of the Cervix

The mechanism for pathogenesis of human papillomavirus (HPV) in the cervix has been investigated intensively. However, detailed differences in the distribution and function of innate immune cells between high-risk HPV types, especially during the chronic inflammation phase, have not been described fully. In this study, histologic pathology results of 245 women with HPV type 16 only (HPV16⁺) or type 18 only (HPV18⁺) were analyzed retrospectively from January 2015 to November 2016. More severe lesions of the cervix were observed in HPV16⁺ women compared with those in HPV18⁺ women. In total, 212 cervical brush specimens were collected from women suffering from chronic inflammation, HPV16⁺, or HPV18⁺ from December 2016 to December 2018. Flow cytometry analysis showed that abundant NK cells along with aberrant Treg cells were found in the HPV16-infected cervix. Quantitative real-time PCR demonstrated that higher expression levels of IFN-γ but muted IL-2 and KLRG-1 expression was detected in the cervix of patients with HPV16⁺ compared to HPV18⁺, which were further confirmed using 20 paraffin sections of cervical conization tissue. The ex vivo cytotoxicity experiment showed that the cytotoxicity of NK cells was significantly decreased in the cervix of HPV16⁺ patients compared with that of HPV18⁺ patients. Collectively, our results suggested that HPV16 disables the increased NK cells in the early lesion of the cervix, indicating that the local immune system of the cervix is hyporesponsive to HPV16 infection and this may explain its bias for malignant transformation.

Three Prime Repair Exonuclease 1 (TREX1) expression correlates with cervical cancer cells growth in vitro and disease progression in vivo

Alterations in specific DNA damage repair mechanisms in the presence of human papillomavirus (HPV) infection have been described in different experimental models. However, the global effect of HPV on the expression of genes involved in these pathways has not been analyzed in detail. In the present study, we compared the expression profile of 135 genes involved in DNA damage repair among primary human keratinocytes (PHK), HPV-positive (SiHa and HeLa) and HPV-negative (C33A) cervical cancer derived cell lines. We identified 9 genes which expression pattern distinguishes HPV-positive tumor cell lines from C33A. Moreover, we observed that Three Prime Repair Exonuclease 1 (TREX1) expression is upregulated exclusively in HPV-transformed cell lines and PHK expressing HPV16 E6 and E7 oncogenes. We demonstrated that TREX1 silencing greatly affects tumor cells clonogenic and anchorage independent growth potential. We showed that this effect is associated with p53 upregulation, accumulation of subG1 cells, and requires the expression of E7 from high-risk HPV types. Finally, we observed an increase in TREX1 levels in precancerous lesions, squamous carcinomas and adenocarcinomas clinical samples. Altogether, our results indicate that TREX1 upregulation is important for cervical tumor cells growth and may contribute with tumor establishment and progression.

Analysis of human papillomavirus 16 E6/E7 and L1 in the bronchial brushing cells of patients with squamous cell carcinoma of the lungs

A type of high-risk human papillomavirus (HPV), HPV16 takes part in lung carcinogenesis. E6 and E7 are the major oncoproteins of high-risk HPV, and L1 is the major capsid protein. In this study, we detected their mRNA expressions and analyzed their relationship in the bronchial brushing cells of 211 patients with malignant lesions (squamous cell carcinoma of the lungs) and benign lesions (pneumonia and tuberculosis) by quantitative real-time PCR. HPV16 E6, E7, and L1 mRNA expressions in the malignant group were statistically higher than in benign group (P<0.05), and their mRNA expressions in the squamous cell carcinoma of the lung group were statistically higher than in pneumonia group (P<0.05). There was a negative correlation between L1 and E6 expression in the squamous cell carcinoma of the lungs group (Spearman correlation coefficient r=-0.498, P=0.000). An ROC curve shows that the combination of L1 and E6 is a significant predictor for the diagnosis of squamous cell carcinoma of the lungs (AUC: 0.878; Sensitivity: 96.00%; Specificity: 77.91%), which could make up for the deficiency of cytologic testing. The combined detection of HPV16 E6 and L1 mRNA expressions in bronchial brushing cells by quantitative real-time PCR has a great significance for the diagnosis of squamous cell carcinoma of the lungs, providing new therapeutic targets for the clinical treatment of squamous cell carcinoma of the lungs.

Human papillomavirus (HPV) 16 E6 oncoprotein targets the Toll-like receptor pathway

Cervical cancer is one of the leading causes of death in women worldwide and is etiologically linked to human papillomavirus (HPV) infection. Viral early proteins E6 and E7 manipulate cellular functions to promote the virus life cycle and are essential to the cellular transformation process. The innate immune system plays a pivotal role in the natural history of HPV infection. Among the various proteins that mediate the innate immune response, Toll-like receptors (TLRs) recognize pathogen-associated molecular patterns (PAMPs) and initiate the immune response. The objective of this study was to identify HPV E6 protein interaction partners in the TLR signalling pathway that may play a role in the immune response against HPV. Six TLR pathway proteins were shown to interact with HPV16 E6: myeloid differentiation primary response protein (MyD88), TIR domain-containing adapter molecule 1 (TRIF), interleukin-1 receptor-associated kinase-like (IRAK) 2, TNF receptor-associated factor (TRAF) 6, I-κB kinase beta (IKKβ) and I-κB kinase epsilon (IKKε). The interaction site of IKKε with E6 is located in the region containing the enzyme catalytic site, suggesting an influence of E6 on the activation of IKKε target proteins. HPV16 E6 potentiated the activation of NF-κB by various TLR pathway members. These results suggest that HPV16 has the ability to interfere with components of the immune response, contributing to HPV carcinogenesis.

A proper triage for detecting women with high-risk human papillomavirus genotypes other than HPV16/18

OBJECTIVE

To evaluate the effect of human papillomavirus (HPV) L1 capsid protein detection in cervical exfoliated cells as a proper triage for women with high-risk human papillomavirus (hrHPV) genotypes other than HPV 16/18.

STUDY DESIGN

From January 2013 to June 2015, a total of 513 women aged 30-65 years infected with non-16/18 hrHPV were enrolled into the study. Primary HPV testing, HPV 16/18 genotyping and Papanicolaou (Pap) test were performed in all eligible women. HPV L1 capsid protein was detected by immunocytochemistry in cervical exfoliated cells. All hrHPV positive women underwent colposcopy and further biopsy if indicated. Relationships between HPV L1 capsid protein expression and histologic diagnosis, as well as cytology were analyzed.

RESULTS

The positive expression rate of HPV L1 capsid protein in CIN2+ group was significantly lower than that in CIN1 or better group (16.3% vs. 66.7%, P=0.000). Compared with the Pap test, HPV L1 detection achieved higher sensitivity (83.7% vs. 51.2%, P=0.000), higher negative predictive value (NPV) (95.3% vs. 88.6%, P=0.002), and significant lower specificity (66.7% vs.76.1%, P=0.002) while identifying CIN2+. Compared with the Pap test, HPV L1 detection achieved higher sensitivity (89.7% vs. 51.7%, P=0.008), higher NPV (99.0% vs. 96.2%, P=0.043), and significant lower specificity (61.2% vs.73.8%, P=0.000) while identifying CIN3+.

CONCLUSION

Because of its higher sensitivity and NPV than that of Pap test, HPV L1 capsid protein detection in cervical exfoliated cells reduces the missed identification of high-grade cervical intraepithelial neoplasia (CIN) in women with hrHPV genotypes other than HPV 16/18. HPV L1 capsid protein detection could be a potential triage for women with non-16/18 hrHPV infection.

Roles of immune inhibitory molecule B7-H4 in cervical cancer

Recent studies have reported that the immune-regulatory protein B7-H4 is highly expressed in various types of cancer, but little is known concerning its roles in cervical cancer. In the present study, we investigated the expression of B7-H4 in human tissues and serum samples, and explored the effects of B7-H4 on proliferation, apoptosis, migration and invasion of cervical cancer cell lines, including SiHa and HeLa. We found that B7-H4 was mainly located in the cytoplasm of cervical cancer cells as determined by immunofluorescence staining. Serum B7-H4 (sB7-H4) was overexpressed in patients with cervical intraepithelial neoplasia (CIN) and cervical cancer, and the area under the ROC curve (AUC) was 0.955. There was no statistical significance between B7-H4 expression and clinicopathological factors in cervical cancer tissue samples. B7-H4 promoted the proliferation of SiHa and HeLa cells, and protected them from apoptosis, which was related to the upregulation of E7, phosphorylated Rb (pRb), E2F, P16, P21, Bcl-2 and the downregulation of Rb, cleaved PARP and cleaved caspase-3 as determined by western blotting. In addition, B7-H4 increased the ability of cell migration and invasion by targeting angiogenic factors, matrix metalloproteinase (MMP)-2, MMP-9 and vascular endothelial growth factor (VEGF) as determined by RT-PCR. Our findings revealed that B7-H4 has the potential to be a useful prognostic marker. In addition, B7-H4 plays important roles in proliferation, apoptosis, migration and invasion, indicating that B7-H4 can serve as a new therapeutic target for cervical cancer.

Vaginal Infections of Albanian women Infected with HPV and their impact in intraepithelial cervical lesions evidenced by Pap test

BACKGROUND

Cervical cytology is the best single method for large screening of the population in identifying precancerous lesions of the uterine cervix.

AIM

To estimate the frequency of human papillomavirus (HPV) positivity in a group of Albanian women, the prevalence of vaginal coinfections, and the relationship of coinfections with HPV, as well as their role in metaplasia or cervical intraepithelial lesions (CIN).

MATERIALS AND METHODS

In this retrospective study, 2075 vaginal smears were examined. The Papanicolaou stain was used for all slides. The New Bethesda System 2001 was used for the interpretations of the smears. Data analysis was completed using the Statistical Package for the Social Sciences version 19.0.

RESULTS

Prevalence of HPV positivity was 43.9% with an average age of 35.48 ± 9.27 years. Candida coinfection resulted in 57.8% of HPV positive women with a significant relationship between them. Gardnerella coinfection resulted in 36 (23%), mixed flora in 34 (8%), and Trichomonas vaginalis in 50% of HPV positive woman. Among the women with positive HPV, 19% had CIN, 8% had metaplasia, and 1% had metaplasia and CIN; 9% of the women with HPV had CIN1 and one of the coinfections.

CONCLUSIONS

There is a strong relationship between CIN1 and HPV positivity as well as between CIN1 and coinfections. HPV infection is a major factor contributing to metaplasia, and bacterial coinfections in HPV positive women have a statistically significant impact in the development of metaplasia.

Nature and Pathogenicity of Micro-organisms

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Micro-organisms and higher organisms have evolved together and interact in complex ways. Only a small percentage of microbes are inherently pathogenic.

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Pathogenicity, the ability of infectious agents to cause disease, must be interpreted in the context of the properties of both transmissible agent and host.

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Understanding this interplay is important to developing methods to prevent infection and reduce the severity of disease.

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The initial step in infection is usually adherence, mediated by the interaction of surface structures on the pathogen with host cell membrane proteins or carbohydrates. This often presents excellent targets for immunity.

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Intracellular pathogens have evolved methods to neutralize the cellular defenses that can destroy invaders.

Humoral Immune Response Against Human Papillomavirus as Source of Biomarkers for the Prediction and Detection of Cervical Cancer

Cervical cancer (CC) is one of the main causes of death among women of reproductive age. Although there are different tests, the disease tends to be diagnosed at late stages. In recent years, the use of complementary tests or sequential diagnostic tests has been implemented. Nevertheless, the results are variable and not conclusive; therefore, more studies for improving the usefulness of these tests in diagnostics are necessary. The human papillomavirus (HPV) infection has been associated with both benign and malignant proliferation of skin and mucosal tissues. Furthermore, some HPV types have been classified as high risk due to their potential to cause cancer, and HPV16 is most frequently associated with this disease. Although between 70% and 80% of precancerous lesions are eliminated by the host's immune system, there is no available test to distinguish between regressive lesions from those that could progress to CC. An HPV infection generates a humoral immune response against L1 and L2 capsid proteins, which can be protective and a response against early proteins. The latter is not a protective response, but these antibodies can be used as markers to determine the stage of the infection and/or the stage of the cervical lesion. Up to now, the humoral immune response resulting from the HPV infection has been used to study the biology of the virus and the efficacy of the HPV vaccines. Although there are no conclusive results regarding the use of these antibodies for diagnosis, we hereby review the actual panorama of the antibody response against the HPV proteins during the development of the disease as well as their possible use as biomarkers for the progression of cervical lesions and of CC.

The prognostic value of p53 expression for patients with cervical cancer: a meta analysis

OBJECTIVE

A number of studies have evaluated the association of p53 expression with the cervical cancer clinical outcome, but the results were inconsistent.

STUDY DESIGN

Electronic search of PubMed was conducted to select studies. Studies which quantitatively evaluated the relationship between p53 expression and survival of the patients with cervical cancer were chosen, and hazard ratio (HR) with 95% confidence interval (CI) was used to assess the association.

RESULTS

The final meta-analysis contained 11 published studies including 1105 patients. Combined HRs suggested that p53 overexpression has an unfavorable impact on overall survival(OS) [HR=1.672, 95% confidence interval (CI): 1.144-2.444, P=0.008], and Caucasian cervical cancer patients OS[HR=1.942, 95% CI: 1.162-3.245, P=0.011].

CONCLUSIONS

p53 expression indicates a poor prognosis for Caucasian people with cervical cancer.

Molecular Detection of Human Papillomavirus and Viral DNA Load after Radiotherapy for Cervical Carcinomas

Aims and background

Infection with high-risk types of human papillomavirus (HPV) is a necessary cause for cervical carcinoma. Radiation therapy together with surgery is the most effective treatment. The purpose of this study was to investigate the molecular basis of the response to radiotherapy in cervical cancer cells.

Methods and study design

Tumor cells were obtained from biopsies of 44 cervical cancers, collected before and after radiotherapy. The presence of HPV was analyzed by polymerase chain reaction (PCR) using primers specific for the L1 region.

Results

The prevalence of HPV was 70.4%, with HPV16 being the most common (54.5%) and HPV18 the second (15.9%). Our analyses show that ionizing radiation does not influence HPV detection, as the percentage of HPV-positive biopsies was similar in patients before and after radiotherapy (HPV16 60% vs. 51.7% and HPV18 20% vs. 13.7%, respectively). However, the detection of HPV did vary by tumor stage, with the highest proportion observed in late-stage tumors (HPV16 and HPV18 in 80% and 60% of stage III tumors, respectively). We also found that HPV viral load is influenced by radiotherapy and tumor stage, with the highest viral loads in late-stage tumors (stage III) after 1 day since radiotherapy (p<0.05). According to Kaplan-Meier curves, higher HPV viral load was associated with significantly shortened progression-free survival (p = 0.04).

Conclusions

Our data provide prospective evidence that ionizing radiation can affect the HPV viral load and this might offer the best strategies for assessment of therapeutic efficacy.

Human Papillomavirus: Current and Future RNAi Therapeutic Strategies for Cervical Cancer

Human papillomaviruses (HPVs) are small DNA viruses; some oncogenic ones can cause different types of cancer, in particular cervical cancer. HPV-associated carcinogenesis provides a classical model system for RNA interference (RNAi) based cancer therapies, because the viral oncogenes E6 and E7 that cause cervical cancer are expressed only in cancerous cells. Previous studies on the development of therapeutic RNAi facilitated the advancement of therapeutic siRNAs and demonstrated its versatility by siRNA-mediated depletion of single or multiple cellular/viral targets. Sequence-specific gene silencing using RNAi shows promise as a novel therapeutic approach for the treatment of a variety of diseases that currently lack effective treatments. However, siRNA-based targeting requires further validation of its efficacy in vitro and in vivo, for its potential off-target effects, and of the design of conventional therapies to be used in combination with siRNAs and their drug delivery vehicles. In this review we discuss what is currently known about HPV-associated carcinogenesis and the potential for combining siRNA with other treatment strategies for the development of future therapies. Finally, we present our assessment of the most promising path to the development of RNAi therapeutic strategies for clinical settings.

Implication of high risk human papillomavirus HR-HPV infection in prostate cancer in Indian population--a pioneering case-control analysis

Prostate cancer is the second most common cancer with sexual history as a consistent risk factor. This is the pioneering study that evaluates the frequency of HPV infection in prostate cancer in India. Ninety five (95) histopathologically confirmed cancer and fifty five (55) BPH from Indian population were analyzed for HPV infection using a pair of consensus sequence primer followed by type specific PCRs for both high-risk and low-risk HPV types. The data demonstrate HPV infection in 41% of prostate tumor biopsies and 20% in BPH. Subsequent PCR- based HPV typing using type - specific primers revealed 32% were infected with HPV type 16 whereas 6% were found to be positive for HPV type 18, while in BPH controls only 5% of the BPH controls were infected with HPV 16 and this difference was highly significant (p = 0.0004). Significant proportion of HPV infected (74%) cases belonged to stage III and IV (p < 0.001) with a high Gleason score ≥8 (p = 0.003). The study represents for the first time the incidence of HPV infection in prostate cancer in Indian population and strengthens the hypothesis that HPV infection could be one of the co factor associated with progression of prostate cancer.

Targeting forkhead box transcription factors FOXM1 and FOXO in leukemia (Review)

Deregulation of forkhead box (FOX) proteins has been found in many genetic diseases and malignancies including leukemia. Leukemia is a common neoplastic disease of the blood or bone marrow characterized by the presence of immature leukocytes and is one of the leading causes of death due to cancer. Forkhead transcription factors, FOXM1 and FOXO family members (FOXOs), are important mediators in leukemia development. Aberrant expression of FOXM1 and FOXOs results in leukemogenesis. Usually the expression of FOXM1 is upregulated, whereas the expression of FOXOs is downregulated due to phosphorylation, nuclear exclusion and degradation in leukemia. On the one hand, FOXOs are bona fide tumor suppressors, on the other hand, active FOXOs maintain leukemia stem cells and stimulate drug resistance genes, contributing to leukemogenesis. FOXM1 and FOXOs have been proven to be potential targets for the development of leukemia therapeutics. They are also valuable diagnostic and prognostic markers in leukemia for clinical applications. This review summarizes the present knowledge concerning the molecular mechanisms by which FOXM1 and FOXOs modulate leukemogenesis and leukemia development, the clinical relevance of these FOX proteins in leukemia and related areas that warrant further investigation.

Human papilloma virus lesions of the oral cavity: healing and relapse after treatment with 810-980 nm diode laser

This study evaluated the therapeutic efficacy of laser therapy in treating oral human papilloma virus (HPV) lesions. In particular, mode of action, healing, postoperative patient compliance, visual numeric scale (VNS) pain index, and recurrence were analyzed. During 2001-2012, in 170 patients (80 women and 90 men), 174 intraoral and lip HPV lesions were detected and excised by diode laser of different wavelengths (810-980 nm), with an average power of 2.1 W, in continuous wave mode, using 300 to 320 μm optical fibers. In most cases (95.4%), complete healing occurred in the first 30 days. There were no adverse effects and all patients were carefully followed up until complete healing occurred, documenting any complications. There was only one recurrence, which was later treated successfully; the mean VNS pain score was below one. In treating HPV lesions, the diode laser is not only a valuable tool for their eradication but especially it reduces relapses, thanks to the characteristics of the laser light.

Mechanistic investigation of immunosuppression in patients with condyloma acuminata

Condyloma acuminatum (CA) is a common sexually transmitted disease caused by human papillomavirus (HPV) infection. Previous studies have identified that the occurrence, relapse and cancerization of CA is relevant to immune imbalance caused by immune hypofunction or immunoregulatory dysfunction. However, to date, the specific mechanisms accounting for immune imbalance in CA patients have remained elusive. In the present study, changes in the expression levels of myeloid differentiation factor 88 (MyD88) and toll‑like receptors (TLRs) were determined in lesion tissues and peripheral blood samples obtained from CA patients by fluorescence quantitative PCR and western blot analysis. The results indicated that TLRs and MyD88 expression was upregulated in the lesion tissues only. In addition, the expression of forkhead box P3, a characteristic marker of regulatory T cells (Tregs), transforming growth factor‑β1 and interleukin (IL)‑10, inhibitory factors secreted by Tregs and inhibitory costimulatory molecules, cytotoxic T-lymphocyte antigen 4, glucocorticoid-induced TNFR-related protein and programmed cell death protein 1 was observed to be upregulated, indicating that immunosuppression of Tregs was enhanced significantly. However, the expression levels of NKG2D and NKp46, natural killer (NK) cell activation receptors located on the surface of NK cells, decreased markedly indicating that HPV infection inhibits the activation of NK cells. The secretion levels of various cytokines in the peripheral blood of CA patients were detected by enzyme‑linked immunosorbent assay revealing that IL‑2, IL‑12 and interferon‑γ levels were markedly lower than that of healthy subjects. By contrast, the expression levels of tumor necrosis factor‑α, IL‑4 and IL‑10 were markedly increased in CA samples compared with the control, with the exception of IL‑6. Taken together, these results are consistent with the hypothesis of immunosuppression in CA patients. Increased expression of MyD88 and TLRs is likely to enhance immunosuppression of Tregs, leading to the imbalance of Th1/Th2, cytotoxic T cell type 1 (Tc1)/Tc2 cells and secreted cytokines.

Detention of HPV L1 Capsid Protein and hTERC Gene in Screening of Cervical Cancer

OBJECTIVE(S)

To investigate the expression of human papilloma virus (HPV) L1 capsid protein, and human telomerase RNA component (hTERC) in cervical cancer and the role of detection of both genes in screening of cervical cancer.

MATERIALS AND METHODS

A total of 309 patients were recruited and cervical exfoliated cells were collected. Immunocytochemistry was employed to detect HPV L1 capsid protein, and fluorescent in situ hybridization (FISH) was performed to detect the hTERC.

RESULTS

The expression of HPV L1 capsid protein reduced with the increase of the histological grade of cervical cells and was negatively related to the grade of cervical lesions. However, the expression of hTERC increased with the increase of the histological grade and positively associated with the grade of cervical lesions. The proportion of patients with L1(-)/hTERC(+) was higher in patients with histological grade of CIN2 or higher than that in those with histological grade of CIN1. The L1(+)/hTERC(-) and L1(-)/hTERC(-) were negatively related to the grade of cervical lesions. L1(-)/hTERC(+) was positively associated with the grade of cervical lesions. The L1/hTERC ratio increased. The negative predictive value of both HPV L1 and hTERC was higher than that of HPV L1 or hTERC, but there was no marked difference in the screening efficacy of cervical cancer among HPV L1, hTERC and HPV L1+hTERC.

CONCLUSION

HPV L1 capsid protein and hTERC gene may serve as markers for the early diagnosis and prediction of cervical lesions. The increase in L1/hTERC ratio reflects the progression of cervical lesions to a certain extent.