Role In Cervical Carcinogenesis Research Articles

High-risk human papillomavirus diversity among indigenous women of western Botswana with normal cervical cytology and dysplasia

BackgroundCervical cancer remains a public health problem despite heavy global investment in health systems especially in low-and-middle-income countries (LMIC). Prophylactic vaccines against the most commonly detected human papillomavirus (HPV) types in cervical cancers are available and decisions on the selection of vaccine design depends on the prevalence of high-risk (hr) HPV genotypes for a particular region. In 2015, Botswana adopted the use of a quadrivalent HPV vaccine as a primary prevention strategy. Secondary prevention includes cervical smear screening whose uptake remains notably low among indigenous and marginalized communities despite efforts to improve access.AimTo determine the prevalence of hrHPV genotypes and cervical lesions’ burden in women from the indigenous and marginalized communities of Botswana.MethodsThis prospective survey enrolled 171 non-HPV vaccinated women aged 21 years and older. Face-to-face interviews, Pap smear screening, hr-HPV and Human Immuno-deficiency virus (HIV) testing were carried out. Conventional Papanicolau smears were analyzed and cervical brushes were preserved for hrHPV testing using the Ampfire Multiplex HR-HPV protocol which detects the following genotypes: HPV 16, 18, 31, 35, 39, 45, 51, 52, 53, 56, 58, 59 and 68.ResultsIn this study, 168/171 (98.6%) of the women consented to HIV testing; 53/171 (31%) were living with HIV and self-reported enrolment on antiretroviral therapy. Among the women examined, 23/171 (13.5%) had cervical dysplasia with most presenting with Atypical Squamous Cells of Undetermined Significance 8/23 (35%), Low-Grade Squamous Intraepithelial Lesions 8/23 (35%), Atypical Squamous Cells-High Grade 4/23 (17%), Atypical Endocervical Cells 2/23 (9%) and Atypical Endocervical Cell favoring neoplasia 1/23(4%). However, no High-Grade Squamous Intraepithelial Lesions (HSIL) or squamous cell carcinoma (SCC) were detected. Overall hrHPV prevalence in this study was at 56/171 (32.7%). The most commonly detected hrHPV genotypes in women with cervical dysplasia were HPV39 (6.25%), HPV51 (14.5%), HPV52 (12.5%) and HPV56 (4%). Notably, HPV 16 and 18 were not found in women with cervical dysplasia.ConclusionsOur study provides valuable insights into the prevalence and distribution of hrHPV genotypes in indigenous and marginalized communities in Botswana, and the need for further investigation of their potential role in cervical carcinogenesis in this population. These results may also serve as baseline data to facilitate future evaluation of the HPV vaccine needs.

Assessing the diagnostic value of CAIX and ProEx-C in cervical squamous intraepithelial lesions

Cervical squamous intraepithelial lesions (SILs) may present a diagnostic challenge due to their morphological similarity to benign conditions and variability in interpretation, necessitating the exploration of objective biomarkers to aid in their identification and grading. This study evaluates the immunohistochemical markers Carbonic Anhydrase IX (CAIX) and ProEx-C to assess their diagnostic potential in cervical SILs. We retrospectively identified 56 SIL cases, including 20 low-grade SILs (LSIL) and 36 high-grade SILs (HSIL), alongside a control group of nine chronic cervicitis cases. Immunohistochemical staining was performed on formalin-fixed, paraffin-embedded tissue blocks, and the sensitivity and specificity of CAIX and ProEx-C were evaluated for detecting and grading SILs. CAIX exhibited a sensitivity of 64.3 % and a specificity of 100 % for detecting SILs. ProEx-C staining displayed a sensitivity of 66.1 % and a specificity of 100 % for detecting SILs. The combination of CAIX and ProEx-C staining increased the sensitivity for detecting SILs to 80.4 % without compromising the specificity. These markers alone or in combination were not found to be significant in distinguishing LSIL from HSIL. Both markers showed positivity in benign endocervical and squamous epithelium in high rates. In conclusion, CAIX and ProEx-C are valuable immunohistochemical markers for detecting SILs in cervical specimens, with high sensitivity and specificity. Further research is needed to elucidate their roles in cervical carcinogenesis and their relationship with HPV infection.

Modern concepts in cervical carcinogenesis

The article discusses modern ideas about cervical carcinogenesis as a multi-stage process of multifactorial genesis. Currently, ideas about the pathogenesis of cervical cancer (CC) are based not only on understanding the role of high-risk oncogenic human papillomavirus (HPV) in this process and accumulation of genetic changes caused by it, but also on formation of a complex HPV interactome, or a network of intermolecular interactions of HPV oncoproteins with host cell proteins. Carcinogenesis also involves a wide range of epigenetic events and, above all, impairment of the regulatory function of miRNAs. An important role in cervical carcinogenesis is attributed to the concept of cancer stem cells (CSCs) formulated in recent years, which is closely related to the explanation of disease recurrence and treatment resistance, as well as to new approaches to treatment. The cervicovaginal microbiome and cervical microenvironment, which are responsible for natural clearance of HPV, regression of epithelial lesions, and modeling of the immune response, are becoming promising objects for research.The aim of the review was to present up-to-date information on the most important mechanisms of cervical carcinogenesis, as well as on new approaches to the treatment of CC, based, in particular, on the use of knowledge about regulatory miRNAs, CSC markers, and the state of the cervicovaginal microbiota.

HLA-G 3'UTR polymorphism diplotypes and soluble HLA-G plasma levels impact cervical cancer susceptibility and prognosis.

Human leukocyte antigen G (HLA-G) is an immune checkpoint molecule with relevance in several cancers. The aim of this study was to evaluate the potential role of soluble HLA-G (sHLA-G), its genetic polymorphisms and its haplotype structure in the susceptibility and prognosis of primary cervical cancer in a Chinese Han population. We investigated sHLA-G plasma levels and 3' untranslated region (3'UTR) polymorphisms through ELISA and direct DNA sequencing, respectively, in cervical cancer patients (120 cases) and healthy control women (96 cases). The data were analyzed for associations using PowerMarker, Haploview, and GraphPad Prism. In this study, 8 polymorphic sites, 16 haplotypes and 23 diplotypes in the HLA-G 3'UTR were identified in our study population. We observed that each pair of 8 polymorphic sites exhibited linkage disequilibrium. The heterozygote CT genotype at position +3422 (rs17875408) was more common in cervical cancer patients than in healthy women (OR=5.285, P<0.05). Haplotypes UTR-1, UTR-3, and UTR-7 accounted for more than 85% of both groups, but no significant difference was found. The frequency of the UTR-1/UTR-3 diplotype in patients was significantly higher than that in controls (P<0.05). In addition, we further observed that HLA-G 3'UTR polymorphisms may influence the sHLA-G plasma level in patients' peripheral blood, especially 14 bp Ins/Del (rs371194629) and +3142 C/G (rs1063320). A receiver operating characteristic (ROC) curve analysis showed that the sHLA-G level had good diagnostic performance in differentiating patients with cervical cancer from healthy women (AUC>0.7). Among patients, mean sHLA-G levels increased with increasing FIGO stages but were not related to the overall survival time. The results of the present study enhance our understanding of how HLA-G 3'UTR polymorphisms can influence the peripheral sHLA-G plasma level and play a key role in cervical carcinogenesis. This study further confirmed that sHLA-G may represent a novel plasma biomarker for the prognosis and potential therapeutic target of cervical cancer.

Association of xenobiotic-metabolizing genes polymorphisms with cervical cancer risk in the Tunisian population.

Host genetic characteristics and environmental factors interactions may play a crucial role in cervical carcinogenesis. We investigated the impact of functional genetic variants of four xenobiotic-metabolizing genes (AhR, CYP1A1, GSTM1, and GSTT1) on cervical cancer development in Tunisian women. The AhR gene polymorphism was analyzed using the tetra-primer ARMS-PCR, whereas the CYP1A1 polymorphism genotypes were identified by PCR-RFLP. A multiplex ligation-dependent polymerase chain reaction approach was applied for the analysis of GSTM1 and GSTT1 polymorphisms. The homozygous A/A genotype of the AhR gene (rs2066853) and the heterozygous T/C genotype of the CYP1A1 SNP (CYP1A1-MspI) appeared to be associated with an increased risk of cervical tumorigenesis (ORa = 2.81; ORa = 5.52, respectively). Furthermore, a significantly increased risk of cervical cancer was associated with the GSTT1 null genotype (ORa = 2.65). However, the null GSTM1 genotype showed any significant association with the risk of cervical cancer compared to the wild genotype (ORa = 1.18; p = 0.784). Considering the combined effect, we noted a significantly higher association with cancer risk for individuals with at least two high-risk genotypes of CYP1A1/GSTT1 (ORa = 4.2), individuals with at least two high-risk genotypes of CYP1A1/GSTT1/AhR (ORa = 11.3) and individuals with at least two high-risk genotypes of CYP1A1/GSTM1/GSTT1/AhR exploitation low-risk genotype as a reference. This study indicated that the single-gene contribution and the combined effect of xenobiotic-metabolizing gene polymorphisms (AhR, CYP1A1-MspI, GSTM1, and GSTT1) may have a considerable association with increased cervical cancer risk.

A Novel Prognostic Risk Model for Cervical Cancer Based on Immune Checkpoint HLA-G-Driven Differentially Expressed Genes.

Human leukocyte antigen G (HLA-G) is a potential checkpoint molecule that plays a key role in cervical carcinogenesis. The purpose of this study was to construct and validate a prognostic risk model to predict the overall survival (OS) of cervical cancer patients, providing a reference for individualized clinical treatment that may lead to better clinical outcomes. HLA-G-driven differentially expressed genes (DEGs) were obtained from two cervical carcinoma cell lines, namely, SiHa and HeLa, with stable overexpression of HLA-G by RNA sequencing (RNA-seq). The biological functions of these HLA-G-driven DEGs were analysed by GO enrichment and KEGG pathway using the “clusterProfiler” package. The protein-protein interactions (PPIs) were assessed using the STRING database. The prognostic relevance of each DEG was evaluated by univariate Cox regression using the TCGA-CESC dataset. After the TCGA-CESC cohort was randomly divided into training set and testing set, and a prognostic risk model was constructed by LASSO and stepwise multivariate Cox regression analysis in training set and validated in testing set or in different types of cervical cancer set. The predictive ability of the prognostic risk model or nomogram was evaluated by a series of bioinformatics methods. A total of 1108 candidate HLA-G-driven DEGs, including 391 upregulated and 717 downregulated genes, were obtained and were enriched mostly in the ErbB pathway, steroid biosynthesis, and MAPK pathway. Then, an HLA-G-driven DEG signature consisting of the eight most important prognostic genes CD46, LGALS9, PGM1, SPRY4, CACNB3, PLIN2, MSMO1, and DAGLB was identified as a key predictor of cervical cancer. Multivariate Cox regression analysis showed that this signature is an independent risk factor for the overall survival of CESC patients. Kaplan-Meier survival analysis showed that the 5-year overall survival rate is 23.0% and 84.6% for the high-risk and low-risk patients, respectively (P<0.001). The receiver operating characteristic (ROC) curve of this prognostic model with an area under the curve (AUC) was 0.896 for 5 years, which was better than that of other clinical traits. This prognostic risk model was also successfully validated in different subtypes of cervical cancer, including the keratinizing squamous cell carcinoma, non-keratinizing squamous cell carcinoma, squamous cell neoplasms, non-squamous cell neoplasms set. Single-sample gene set enrichment (ssGSEA) algorithm and Tumor Immune Dysfunction and Exclusion (TIDE) analysis confirmed that this signature influence tumour microenvironment and immune checkpoint blockade. A nomogram that integrated risk score, age, clinical stage, histological grade, and pathological type was then built to predict the overall survival of CESC patients and evaluated by calibration curves, AUC, concordance index (C-index) and decision curve analysis (DCA). To summarize, we developed and validated a novel prognostic risk model for cervical cancer based on HLA-G-driven DEGs, and the prognostic signature showed great ability in predicting the overall survival of patients with cervical cancer.

Human papillomavirus targets the YAP1-LATS2 feedback loop to drive cervical cancer development.

Human papillomavirus (HPV) infection is very common in sexually active women, but cervical cancer only develops in a small fraction of HPV-infected women, suggesting that unknown intrinsic factors associated with the unique genetic/genomic background of the high-risk population play a critical role in cervical carcinogenesis. Although our previous studies have identified the hyperactivated YAP1 oncogene as a critical contributor to cervical cancer, the molecular mechanism by which YAP1 drives cervical cancer is unknown. In the present study, we found that although the hyperactivated YAP1 caused a malignant transformation of immortalized cervical epithelial cells, it induced cellular senescence in cultures of primary human cervical epithelial cells (HCvECs). However, the hyperactivated YAP1 induced malignant transformation of HCvECs in the presence of high-risk HPV E6/E7 proteins, suggesting that the hyperactivated YAP1 synergizes with HPV to initiate cervical cancer development. Our mechanistic studies demonstrate that YAP1, via up-regulating LATS2, formed a YAP1-LATS2 negative feedback loop in cervical epithelial cells to maintain homeostasis of cervical tissue. Intriguingly, we found that high-risk HPV targets LATS2 to disrupt the feedback loop leading to the malignant transformation of cervical epithelial cells. Finally, we report that mitomycin C, an FDA-approved drug that could upregulate LATS2 and drive cellular senescence in vitro and in vivo, induced a regression of cervical cancer in a pre-clinial animal model. Thus, high-risk HPV targeting the YAP1-LATS2 feedback loop represents a new mechanism of cervical cancer development.

Altered Vaginal pH Value and Enterobacteria as a Risk Factor in the Development of Precancerous Lesions of the Cervix

Background: Vaginal microflora plays an important role in cervical carcinogenesis. An increase in vaginal pH is associated with the severity of squamous intraepithelial lesion (SIL) and a decrease in the number of lactobacilli. Microbial dysbiosis contributes to the damage of the epithelial barrier, as well as the reprogramming of immune and metabolic signaling. Dysbiotic bacteria cause damage to the epithelial barrier, immune dysregulation and genotoxicity and create a tumor-permissive microenvironment. Objective: The aim of this study was to determine the presence of risk factors (abnormal colposcopic and microbiological status, elevated pH of the vaginal environment) in regular Pap tests and LSIL. Methods: Retrospective prospective study 2021-2022. 90 women with pap smears were analyzed: 40 with LSIL at the Gynecological Center “Dr. Mahira Jahić” Tuzla and 50 with normal findings at the Tesanj Health Center. General data such as: age of the subjects, reproductive status, contraception, smoking and data on colposcopic examination, microbiological findings and vaginal pH value were analyzed. Statistical data processing was done in the SPSS program. Results: The average age of the test subjects is 39.94, in normal Pap 41.20 years, and in LSIL 38.38 years. The vital characteristics of the subjects did not differ significantly, except for smoking, where in LSIL findings, they consumed cigarettes significantly more often. Abnormal colposcopic examination were found in 85% (N-34) of women with LSIL. In subjects with LSIL, a positive microbiological test for enterobacteria was found in 47.5% (N-19) and a normal pap test in 12% (N-6). Statistically significant difference p=0.00523 p&lt;0.05, E faecalis and E coli had the highest prevalence in LSIL. The mean pH value of the vaginal environment in LSIL is 5.38, and 4.96 in a regular pap test. Subjects with LSIL in 10% (N-4) had a normal pH test, and 48% (N-24) had a normal Pap test. P=0.00129 p &lt; (0.05). A normal pH value was significantly more common in subjects with a normal Pap test. Microbiological flora, especially enterogenic bacteria, are more common in LSIL than in women with a regular pap test. Conclusion: when monitoring women with LSIL, special attention should be paid to the elimination of present enterobacteria (E.faecalis and E.coli) as a possible risk factor in the development of precancerous lesions (SIL) and cervical cancer.

HPV16 E1 dysregulated cellular genes involved in cell proliferation and host DNA damage: A possible role in cervical carcinogenesis.

HPV16 is the most prominent cause of cervical cancer. HPV16 E1, a helicase required for HPV replication exhibits increased expression in association with cervical cancer progression, suggesting that E1 has a similar effect on the host as the HPV16 E6 and E7 oncoproteins. This study aimed to determine whether expression of HPV16 E1 correlated with carcinogenesis by modulating cellular pathways involved in cervical cancer. HEK293T cells were transfected with pEGFP, pEGFPE1 or truncated forms of HPV16 E1. Cell proliferation, cell death, and the impact of HPV16 E1 on host gene expression was then evaluated. HPV16 E1 overexpression resulted in a significant reduction of cell viability and cellular proliferation (p-value<0.0001). Moreover, prolonged expression of HPV16 E1 significantly induced both apoptotic and necrotic cell death, which was partially inhibited by QVD-OPH, a broad-spectrum caspase inhibitor. Microarray, real time RT-PCR and kinetic host gene expression analyses revealed that HPV16 E1 overexpression resulted in the downregulation of genes involved in protein synthesis (RPL36A), metabolism (ALDOC), cellular proliferation (CREB5, HIF1A, JMJDIC, FOXO3, NFKB1, PIK3CA, TSC22D3), DNA damage (ATR, BRCA1 and CHEK1) and immune response (ISG20) pathways. How these genetic changes contribute to HPV16 E1-mediated cervical carcinogenesis warrants further studies.

Cervical Squamous Intraepithelial Lesions Are Associated with Differences in the Vaginal Microbiota of Mexican Women.

ABSTRACTCervical cancer is an important health concern worldwide and is one of the leading causes of death in Mexican women. Previous studies have shown changes in the female genital tract microbe community related to human papillomavirus (HPV) infection and cervical cancer; yet, this link remains unexplored in many human populations. This study evaluated the vaginal bacterial community among Mexican women with precancerous squamous intraepithelial lesions (SIL). We sequenced the V3 region of the 16S rRNA gene in cervical samples from 228 Mexican women, including 121 participants with SIL, most of which were HPV positive, and 107 healthy women without HPV infection or SIL. The presence of SIL was associated with changes in composition (beta diversity) and with a higher species richness (Chao1). A comparison of HPV-positive women with and without SIL showed that microbiota changes occurred even in the absence of SIL. Multivariate association with linear models (MaAsLin) analysis yielded independent associations between HPV infection and an increase in the relative abundance of Brachybacterium conglomeratum and Brevibacterium aureum as well as a decrease in two Lactobacillus iners operational taxonomic units (OTUs). We also identified a positive independent association between HPV-16, the most common HPV subtype linked to SIL, and Brachybacterium conglomeratum. Our work indicates that HPV infection leading to SIL is primarily associated with shifts in vaginal microbiota composition, some of which may be specific to this human population.IMPORTANCE Human papillomavirus (HPV) plays a critical role in cervical carcinogenesis but is not sufficient for cervical cancer development, indicating the involvement of other factors. The vaginal microbiota is an important factor in controlling infections caused by HPV, and, depending on its composition, it can modulate the microenvironment in vaginal mucosa against viral infections. Ethnic and sociodemographic factors influence differences in vaginal microbiome composition, which underlies the dysbiotic patterns linked to HPV infection and cervical cancer across different populations of women. Here, we provide evidence for associations between vaginal microbiota patterns and HPV infection linked to ethnic and sociodemographic factors. To our knowledge, this is the first report of the species Brevibacterium aureum and Brachybacterium conglomeratum linked to HPV infection or squamous intraepithelial lesions (SIL).

Multiple Human Papilloma Virus (HPV) Infections Are Associated with HSIL and Persistent HPV Infection Status in Korean Patients.

Infections with multiple human papilloma virus (HPV) types have been reported, but their role in cervical carcinogenesis has not been fully elucidated. In this study, 236 cases with multiple HPV infection were examined and compared to 180 cases with single HPV infection. HPV genotyping was performed with cervico-vaginal swab specimens using multiplex (real-time) polymerase chain reaction (PCR). In multiple HPV infection, the most prevalent HPV genotype was HPV 53, followed by HPV 16, 58, 52, and 68. HPV 33, 35, 39, 51, 52, 53, 58, and 68 were high-risk-HPV (HR-HPV) genotypes that were more frequently detected in multiple HPV infection compared to that in single HPV infection. The association between multiple HPV infection and high-grade SIL (HSIL) was significantly stronger compared to that of single HPV infection and HSIL (p = 0.002). Patients with multiple HPV infection displayed persistent and longer duration of the HPV infection compared to patients with single HPV infection. Multiple HPV infections have distinct clinicopathologic characteristics. Since it is associated with persistent HPV infection, HSIL, and different HR-HPV strains in contrast to single HPV infection, the presence of multiple HPV infection should be reported; close follow up is warranted.

Expression of miR-34a and miR-15b during the progression of cervical cancer in a murine model expressing the HPV16 E7 oncoprotein.

The high-risk human papillomavirus (HR-HPV) E7 oncoprotein appears to be a major determinant for cell immortalization and transformation altering critical processes such as cell proliferation, apoptosis, and immune response. This oncoprotein plays an essential role in cervical carcinogenesis, but other cofactors such as long-term use of hormonal contraceptives are necessary to modulate the risk of cervical cancer (CC). The role of HR-HPVs in the alteration of microRNA (miRNA) levels in persistent viral infections currently remains unclear. The aim of this study was to evaluate the miR-34a and miR-15b expression levels in the murine HPV16K14E7 (K14E7) transgenic model after chronic estrogen (E2) treatment and their involvement in CC. Interestingly, results showed that, although miR-34a expression is elevated by the HPVE7 oncogene, this expression was downregulated in the presence of both the E7 oncoprotein and chronic E2 in cervical carcinoma. On the other hand, miR-15b expression was upregulated along cervical carcinogenesis mainly by the effect of E2. These different changes in the expression levels of miR-34a and miR-15b along cervical carcinogenesis conduced to low apoptosis levels, high cell proliferation and finally, to cancerous cervical tissue development. In this work, we also determined the relative mRNA expression of Cyclin E2 (Ccne2), Cyclin A2 (Ccna2), and B cell lymphoma 2 (Bcl-2) (target genes of miR-34a and miR-15b); Sirtuin 1 (Sirt1), Cmyc, and Bax (miR-34a target genes); and p21/WAF1 (mir15b target gene) and the H-ras oncogene. Given the modifications in the expression levels of miR-34a and miR-15b during the development of cervical cancer, it will be useful to carry out further investigation to confirm them as molecular biomarkers of cancer.

Integrated bioinformatic analysis of miR-15a/16-1 cluster network in cervical cancer

The miR-15a/16-1 cluster is abnormally expressed in cervical cancer (CC) tissues and plays a vital role in cervical carcinogenesis. We aimed to evaluate the miR-15a/16-1 expression in healthy and cancerous cervical tissues, identify the associated networks, and to test its prognostic significance. miR-15a/16-1-MC expressions were analyzed in TCGA-CESC datasets by UALCAN, GEPIA2, and Datasetviewer. miR-15a/16-1 validated targets were extracted from mirTarBase and in silico functional analysis of the target genes were performed using WebGestalt. The interaction networks were constructed by the miRNet, STRING, and NetworkAnalyst tools. The prognostic significance and metastatic potential of the target genes were predicted using UALCAN and HCMDB. The FDA approved drugs to target miR-15a/16-1 and target gene network in CC were performed using DGIdb, STITCH and PanDrugs. TCGA-CESC and GEO data analysis suggested significant overexpression of miR-15a/16-1 in CC samples. The Kaplan-Meier survival analysis showed that miR-15a and its four target genes (BCL2, CCNE1, NUP50, and RBPJ) influence the overall survival of CC patients. Among the 66 differentially expressed target genes, 12 of them are linked to head, neck, or lung metastasis. Functional enrichment analysis predicted the association of this cluster with p53 signaling, human papillomavirus infection, PI3-AKT signaling pathway, and pathways in cancer. Drug-gene interaction analysis showed 52 potential FDA approved drugs to interact with the miR-15a/16-1 target genes. Nine of the 52 drugs are currently used as a chemotherapeutic agent for the treatment of CC patients. The present study shows that miR-15a/16-1 expression can be used as a clinical marker and target for therapy in CC.

ERRATUM.

It has been demonstrated that microRNAs (miRNAs) act as oncogenes or tumor suppressors in a variety of cancers. Our previous work suggested that miR-10a/b functioned as a tumor suppressor in gastric cancer, and miR-10b was also reported to be significantly downregulated in advanced stage cervical cancer tissues. However, the aberrant expression of miR-10b in cervical cancer and its possible role in cervical carcinogenesis was largely unknown. In this study, we investigated the expression of miR-10b in cervical cancer tissues, carcinoma in situ tissues, mild dysplasia, moderate dysplasia, severe dysplasia tissues, and normal controls. We found that miR-10b was significantly downregulated during cervical cancer progression, and the lower level of miR-10b in cervical cancer was significantly associated with a more aggressive tumor phenotype. Moreover, overexpression of miR-10b in cervical cancer cells could inhibit the cell proliferation and invasion, and the further mechanism study suggested that its role was possibly through directly targeting HOXA1. These results suggested that the downregulation of miR-10b and the resulting elevated HOXA1 level in cervical cancer tissues might play critical roles in cervical cancer progression.

HPV16 E6 oncoprotein-induced upregulation of lncRNA GABPB1-AS1 facilitates cervical cancer progression by regulating miR-519e-5p/Notch2 axis.

Human papillomaviruses 16 (HPV16) is the primary causative agent of cervical cancer (CC). E6 oncoprotein plays a crucial role in cervical carcinogenesis and commonly cause the dysregulation of the long noncoding RNAs (lncRNAs) expression. However, the biological function of lncRNAs in HPV16-related CC remains largely unexplored. In the present study HPV16 E6-induced differential expression of lncRNAs, miRNA, and mRNA were identified using microarray-based analysis and verified in tumor r cell lines and tumor tissues, and the function of lncRNA in CC was investigated in vitro and in vivo. We found that an lncRNA, named GABPB1-AS1, was significantly upregulated in HPV16-positive CC tissues and cell lines. GABPB1-AS1 expression in HPV16-positive CC tissues was positively associated with tumor size, lymph node metastasis, and FIGO stage. High expression of GABPB1-AS1 was correlated with a poor prognosis for HPV16-positive CC patients. Functionally, E6-induced GABPB1-AS1 overexpression facilitated CC cells proliferation and invasion in vitro and in vivo. Mechanistically, GABPB1-AS1 acted as a competing endogenous RNA (ceRNA) by sponging miR-519e-5p, resulting in the de-repression of its target gene Notch2 which is well known as an oncogene. Therefore, GABPB1-AS1 functioned as a tumor activator in CC pathogenesis by binding to miR-519e-5p and destroying its tumor suppressive function. Collectively, current results demonstrate that GABPB1-AS1 is associated with CC progression, and may be a promising biomarker or target for the clinical management of CC.

Role of Epstein-Barr Virus and Human Papillomavirus Coinfection in Cervical Cancer: Epidemiology, Mechanisms and Perspectives.

High-risk human papillomavirus (HR-HPV) is etiologically associated with the development and progression of cervical cancer, although other factors are involved. Epstein-Barr virus (EBV) detection in premalignant and malignant tissues from uterine cervix has been widely reported; however, its contribution to cervical cancer development is still unclear. Here, a comprehensive analysis regarding EBV presence and its potential role in cervical cancer, the frequency of EBV/HR-HPV coinfection in uterine cervix and EBV infection in tissue-infiltrating lymphocytes were revised. Overall, reports suggest a potential link of EBV to the development of cervical carcinomas in two possible pathways: (1) Infecting epithelial cells, thus synergizing with HR-HPV (direct pathway), and/or (2) infecting tissue-infiltrating lymphocytes that could generate local immunosuppression (indirect pathway). In situ hybridization (ISH) and/or immunohistochemical methods are mandatory for discriminating the cell type infected by EBV. However, further studies are needed for a better understanding of the EBV/HR-HPV coinfection role in cervical carcinogenesis.

A novel mechanism by which ACTA2-AS1 promotes cervical cancer progression: acting as a ceRNA of miR-143-3p to regulate SMAD3 expression

BackgroundLong non-coding RNAs (LncRNAs) have been increasingly confirmed to be abnormally expressed in human cancer and closely related to tumorigenesis. LncRNA ACTA2-AS1 is abnormally expressed in multiple tumors and participates in their development. However, whether ACTA2-AS1 plays a role in the development of cervical cancer (CC) and the exact mechanism of its role has not been elucidated.MethodsQuantitative real-time PCR (qRT-PCR) was conducted to detect the expression level of messenger RNA of ACTA2-AS1, miR-143-3p and SMAD3 in tumor tissues and cells. Additionally, SMAD3 protein expression by western blots in cells. Small interference RNA against ACTA2‐AS1 or SMAD3 and miR‐143‐3p mimic/inhibitor was designed and transfected into CC cell lines to investigate their correlations and potential impacts on cell function. Cell Counting Kit-8 (CCK-8) assay, colony formation, cell cycle assay, transwell assay and flow cytometry analysis were performed to detect the specific effects on cell line proliferation, metastasis and apoptosis.ResultsACTA2-AS1 was significantly increased in CC tissues and cells and miR‐143‐3p was down-regulated. Clinically, the higher expression of ACTA2-AS1 was significantly correlated with higher FIGO stage. Loss-of-function assay revealed that silencing of ACTA2-AS1 inhibited cell proliferation, colony formation, migration and promoted apoptosis in CC. Additionally, Pearson correlation analysis showed that the expression of ACTA2-AS1 and miR-143-3p were negatively correlated. Dual-luciferase reporter assay and further mechanistic experiments confirmed that ACTA2-AS1 could sponge and regulate the expression of miR-143-3p. Furthermore, SMAD3 was the target gene of miR-143-3p and ACTA2-AS1 could upregulate SMAD3 through acting as a competitive endogenous RNA (ceRNA) of miR-143-3p. Finally, rescue assay demonstrated that the ACTA2-AS1/miR-143-3p/SMAD3 axis played an important role in the proliferation, migration and apoptosis of CC cells.ConclusionsIn summary, our study revealed that ACTA2-AS1 upregulates SMAD3 by competitively binding miR-143-3p, thereby accelerating CC progression. The ACTA2-AS1/miR-143-3p/SMAD3 axis can play a crucial role in cervical carcinogenesis, providing new clues for the early diagnosis and treatment of CC.

Genetic predisposition for cervical cancer

Aim: to assess a role of genetic factors and human papillomavirus (HPV) in developing cervical neoplasia based on analyzing current publications on virus-induced carcinogenesis.Materials and methods. A systematic overview on publications dedicated to examining genetic predisposition to developing cervical cancer (CC) available in electronic databases was performed by searching in the International Scientific Databases (ISDB) PubMed/MEDLINE as well as manually by accessing enlisted input documents related to the above noted studies. Full-text publications were solely selected for analysis.Results. CC is a multifactorial disease implicating host genetic predisposition being caused by persistent high oncogenic risk HPV-infection. Immune system plays a major role in HPV-infection. Altered cell-mediated immune response is responsible for impaired potential to HPV eradication. On the other hand, immune evasion contributes to viral persistence and cancer progression. Oncogenes, cancer suppressor genes (Rb and TP53), cytokine (ILs, IFNG) and chemokine (CXCL) genes, the genes involved in antigen processing, as well as an impact for each gene polymorphism or even haplotypes playing a role in cervical carcinogenesis are mainly involved in CC developing.Conclusion. The data obtained allowed to demonstrate a role for genetic polymorphisms in the genes encoding cytokines, chemokines, diverse receptors as well as those involved in antigen processing, and cancer suppressor genes in perpetuation of HPV-infection.

Abstract B56: YAP1 inhibits host cell immunity and increases human papillomavirus (HPV) infection to drive cervical tumorigenesis

Abstract Although human papillomavirus (HPV) is believed to be the major causative agent for cervical cancer, accumulating evidence indicates that HPV alone is insufficient to induce cervical cancer. The molecular mechanisms underlying cervical cancer development remain unclear. In the present study, we provide evidence showing that the Hippo/YAP pathway plays a critical role in cervical carcinogenesis. We found that genetic alteration of the Hippo/YAP pathway frequently occurred in human cervical cancer patients and was associated with poor prognosis of these patients. Keratin 14 promoter-driven expression of constitutively active YAP1 (YAP S127A) in mouse cervical epithelial cells induced invasive cervical squamous cell carcinoma (CVSCC), suggesting that hyperactivation of YAP1 is sufficient to induce cervical cancer. Importantly, hyperactivation of YAP1 in cervical epithelial cells not only increased the putative HPV receptor molecules and cellular susceptibility to HPV infection, but also disrupted the host cell innate immune system, resulting in failure of HPV viral recognition, suppression of type I IFN production, inhibition of the IFNRs/JAKs/STATs pathway, and blockage of production of antiviral interferon-stimulated genes. Cervical epithelial-specific YAP1 and HPV double knockin mouse models showed that YAP1 synergizes with HPV to promote the initiation and progression of CVSCC. The present study demonstrates that the Hippo/YAP pathway plays a central role in the development of CVSCC and the synergism between hyperactivated YAP1 and high-risk HPV may be the key driver of cervical cancer development. The Hippo/YAP signaling pathway may represent a promising target for developing novel strategies to prevent and treat cervical cancer. Citation Format: Xiangmin Lv, Chunbo He, Cong Huang, Hongbo Wang, Li Chen, Peichao Chen, John S. DavisS, Bo R. Rueda, Cheng Wang. YAP1 inhibits host cell immunity and increases human papillomavirus (HPV) infection to drive cervical tumorigenesis [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr B56.

Indoleamine 2,3-dioxygenase and tryptophan 2,3-dioxygenase expression in HPV infection, SILs, and cervical cancer.

Human papillomavirus (HPV) infection is the central factor for cervical cancer, whereas epithelial immune mechanisms contribute to the progression of HPV infection and its associated lesions. The authors evaluated the expression of indoleamine 2,3-dioxygenase (IDO) and tryptophan 2,3-dioxygenase (TDO) in cervicovaginal samples from women with normal cervical epithelium or with different degrees of squamous intraepithelial lesions (SILs) and cervical cancer. IDO expression was analyzed by immunocytochemistry in liquid-based cytology samples from 165 women, of whom 42 had cervical changes subclassified as low-grade SIL (n=6), high-grade SIL (n=30), or squamous cell carcinoma (SCC) (n=6), and 123 had negative Papanicolaou smears. IDO and TDO expression also were analyzed by immunohistochemistry, and HPV and other genital pathogens were evaluated by polymerase chain reaction analysis. Low IDO expression was observed in normal cervical epithelium irrespective of HPV status. Increased numbers of IDO-positive squamous cells and IDO-positive leukocytes were observed in women with SIL or SCC. TDO expression was detected in leukocytes infiltrating the stroma around intraepithelial or invasive cervical lesions. Higher IDO levels were detected in organotypic epithelial cultures established from keratinocytes transduced with the HPV16 E6/E7 oncoproteins. The upregulation of IDO expression in leukocytes and squamous cells in HPV-associated SIL and SCC suggests that immunosuppressive mechanisms involving tryptophan metabolism may have a role in cervical carcinogenesis. Although previous studies have suggested the role of IDO in HPV pathogenesis, this is the first evidence of TDO involvement in the process. Furthermore, the current data emphasize the role of leukocytes, especially neutrophil-like cells, as an IDO source.