Human papillomavirus in endometrial adenocarcinomas: infectious agent or a mere "passenger"?

Primary adenosquamous carcinoma of the endometrium with glassy cell features. A diagnostic pitfall as a very rare tumour type in the endometrium

Primary adenosquamous carcinoma of the endometrium with glassy cell features (ASCGCF) is an extremely rare entity and to date, 16 cases of this entity have been reported in the literature. ASC-GCF is an aggressive histological subtype of cervical carcinoma with rapid growth and early metastases; however, very little is known about those originating from the endometrium as they are limited to only a few case reports. Herein, we report a case of primary adenosquamous carcinoma of the endometrium with extensive glassy cell features which posed a major diagnostic challenge by mimicking many entities with its histological diversity.

Human Papillomaviruses as Infectious Agents in Gynecological Cancers. Oncogenic Properties of Viral Proteins

Human papillomaviruses (HPVs), which belong to the Papillomaviridae family, constitute a group of small nonenveloped double-stranded DNA viruses. HPV has a small genome that only encodes a few proteins, and it is also responsible for 5% of all human cancers, including cervical, vaginal, vulvar, penile, anal, and oropharyngeal cancers. HPV types may be classified as high- and low-risk genotypes (HR-HPVs and LR-HPVs, respectively) according to their oncogenic potential. HR-HPV 16 and 18 are the most common types worldwide and are the primary types that are responsible for most HPV-related cancers. The activity of the viral E6 and E7 oncoproteins, which interfere with critical cell cycle points such as suppressive tumor protein p53 (p53) and retinoblastoma protein (pRB), is the major contributor to HPV-induced neoplastic initiation and progression of carcinogenesis. In addition, the E5 protein might also play a significant role in tumorigenesis. The role of HPV in the pathogenesis of gynecological cancers is still not fully understood, which indicates a wide spectrum of potential research areas. This review focuses on HPV biology, the distribution of HPVs in gynecological cancers, the properties of viral oncoproteins, and the molecular mechanisms of carcinogenesis.

Effects of Induced Exosomes from Endometrial Cancer Cells on Tumor Activity in the Presence of Aurea helianthus Extract

Endometrial cancer (EC) cells metastasize to various regions, including the ovaries, fallopian tubes, cervix, blood, liver, bone, and brain. Various carcinogens are known to cause EC. Exosomes are released from several types of cells and contain various cellular components. In this study, flow cytometry and quantitative PCR were used to evaluate marker levels, cell migration, cell invasion, and mitochondrial membrane potential, and cellular senescence tests were used to estimate cancer activity. The microRNAs were profiled using next-generation sequencing. Although tocopherol-α and rutin content in Aurea helianthus is high, A. helianthus extract was more useful in modulating tumor activity compared to the two aforementioned substances. Notably, we established that the extract induced bioactive exosomes in EC cells, and profiling of miRNAs in the extract-inducing exosomes (EIE) indicated their potency to be developed as a biological drug. The extract and EIE contributed to the following five biological process categories for EC cells: (1) cell migration and invasion suppression, (2) cellular senescence activation by attenuating mitochondrial membrane potential and enhancing autophagy, (3) reproductive cancer activity attenuation, (4) drug susceptibility activation, and (5) EIE containing miRNAs associated with decreasing inflammation.

Low Expression of miR-375 and miR-190b Differentiates Grade 3 Patients with Endometrial Cancer

Endometrial cancer (EC) is treated according to the stage and prognostic risk factors. Most EC patients are in the early stages and they are treated surgically. However some of them, including those with high grade (grade 3) are in the intermediate and high intermediate prognostic risk groups and may require adjuvant therapy. The goal of the study was to find differences between grades based on an miRNA gene expression profile. Tumor samples from 24 patients with grade 1 (n = 10), 2 (n = 7), and 3 (n = 7) EC were subjected to miRNA profiling using next generation sequencing. The results obtained were validated using the miRNA profile of 407 EC tumors from the external Cancer Genome Atlas (TCGA) cohort. We obtained sets of differentially expressed (DE) miRNAs with the largest amount between G2 to G1 (50 transcripts) and G3 to G1 (40 transcripts) patients. Validation of our results with external data (TCGA) gave us a reasonable gene overlap of which we selected two miRNAs (miR-375 and miR190b) that distinguish the high grade best from the low grade EC. Unsupervised clustering showed a high degree of heterogeneity within grade 2 samples. MiR-375 as well as 190b might be useful to create grading verification test for high grade EC. One of the possible mechanisms that is responsible for the high grade is modulation by virus of host morphology or physiology.

Human papillomavirus as an independent risk factor of invasive cervical and endometrial carcinomas in Jordan

BACKGROUND

Endometrial and cervical carcinomas are the most common gynecologic malignancies in Western world and many countries. The human papillomavirus (HPV) high-risk genotypes are associated with cervical carcinoma (CC). Chlamydia trachomatis (C. trachomatis), the most common sexually transmitted bacterial infection worldwide, considered a cofactor for HPV infection and CC. Information on HPV infection rate and type distribution among Jordanian women having CC is currently limited and unavailable among those with endometrial carcinoma. Therefore, the present study aimed to provide an updated estimate on HPV infection rate and its high-risk genotypes' distribution among Jordanian women by comparing data from invasive cervical carcinoma (ICC) to normal cervical tissues. Similarly, assessment of HPV infection rate was extended to the endometrial tissues. C. trachomatis infection was investigated as well to explore its possibility as HPV cofactor for induction of such carcinomas.

METHODS

Total DNA was extracted from 144 formaldehyde-fixed paraffin-embedded cervical and endometrial tissue, equally divided between age-matched control and carcinoma cases. Polymerase chain reaction (PCR) was used for general detection of HPV-DNA, high risk HPV-16 and 18 genotypes and C. trachomatis DNA using specific primers.

RESULTS

HPV infection was detected in 91.7% and 61.1% of cervical cancer patients and controls, respectively. Likewise, it was higher among cases (47.2%) than controls (13.8%) in endometrial biopsies. Significantly higher HPV infection rates were found among ICC and endometrial control biopsies of women >50 years. Out of 33 HPV positive ICC cases, single HPV-16 infections were detected in 69.7% compared to HPV-18 (15.2%), while HPV-16/18 co-infections were only found in three (9%) samples. C. trachomatis was not detected in all studied groups.

CONCLUSION

The present study has successfully provided an updated estimate on HPV infection rate among Jordanian women with and without ICC and endometrial carcinoma. In addition, a lack of co-infection was observed between HPV and C. trachomatis in both cancer types.

Meta-analysis of gene expression studies in endometrial cancer identifies gene expression profiles associated with aggressive disease and patient outcome

Although endometrioid endometrial cancer (EEC; comprising ~80% of all endometrial cancers diagnosed) is typically associated with favourable patient outcome, a significant portion (~20%) of women with this subtype will relapse. We hypothesised that gene expression predictors of the more aggressive non-endometrioid endometrial cancers (NEEC) could be used to predict EEC patients with poor prognosis. To explore this hypothesis, we performed meta-analysis of 12 gene expression microarray studies followed by validation using RNA-Seq data from The Cancer Genome Atlas (TCGA) and identified 1,253 genes differentially expressed between EEC and NEEC. Analysis found 121 genes were associated with poor outcome among EEC patients. Forward selection likelihood-based modelling identified a 9-gene signature associated with EEC outcome in our discovery RNA-Seq dataset which remained significant after adjustment for clinical covariates, but was not significant in a smaller RNA-Seq dataset. Our study demonstrates the value of employing meta-analysis to improve the power of gene expression microarray data, and highlight genes and molecular pathways of importance for endometrial cancer therapy.

HPV11 Positive Endometrioid Carcinoma of the Endometrium with Signet-Ring Cells: Diagnostic Criteria and Review of the Literature

The presence of signet-ring cells in an endometrial adenocarcinoma is extremely uncommon and it is always necessary to rule out a metastatic neoplasm. We report a FIGO grade 2 endometrial carcinoma with a signet-ring cell component found in the curettage performed to a 53-year-old woman. The neoplastic proliferation was also found in the endometrium of the radical hysterectomy with bilateral salpingo-oophorectomy and pelvic and para-aortic lymphadenectomy. The uterine neoplasm invaded less than one-half of the myometrium (FIGO stage I B). Alcian blue showed the presence of mucin in the signet-ring cells. The patient was alive and without evidence of recurrence 14 months after surgery. Polymerase chain reaction method from paraffin-embedded tissue revealed the presence of human papilloma virus type 11. We have discussed the differential diagnosis of this kind of neoplasm and we have reviewed the literature on signet-ring cell carcinoma of the endometrium.

Prevalence of Human Papillomavirus in endometrial cancer: a systematic review and meta-analysis

OBJECTIVE

HPV is a common sexually transmitted infection and is considered to be a necessary cause of cervical cancer. The anatomical proximity to the cervix has led researchers to investigate whether Human Papillomavirus (HPV) has a role in the etiology of endometrial cancer.

METHODS

We conducted a systematic review and meta-analysis to investigate the pooled prevalence of HPV DNA in endometrial cancer. Using meta-regression, we further analyzed whether factors such as geographical region, HPV DNA detection method, publication year and tissue type were associated with HPV prevalence. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were calculated for studies providing data on HPV prevalence in cases with endometrial cancer and in controls with normal or hyperplastic endometrial tissue.

RESULTS

We identified 28 papers (29 studies) examining the prevalence of HPV DNA in tumor tissue from endometrial cancer comprising altogether 1026 cases of endometrial cancer. The HPV prevalence varied considerably from 0% to 61.1%. From the random effects meta-analysis, the pooled prevalence of HPV DNA in endometrial cancer was 10.0% (95% CI: 5.2-16.2) with large between-study heterogeneity (I(2)=88.2%, p<0.0001). The meta-regression showed that HPV DNA detection method was statistically significantly associated with HPV prevalence (p=0.0016): the pooled HPV prevalence was 6.0% (95% CI: 1.5-13.0) using general primers, 18.9% (95% CI: 8.6-32.1) using type-specific primers and 1.0% (95% CI: 0.0-3.6) using non-PCR based methods. None of the other a priori defined variables were statistically significantly associated with HPV prevalence. The pooled OR was 1.43 (95% CI: 0.68-3.00) indicating that the odds of HPV was not increased in cases versus controls.

CONCLUSIONS

HPV appears to have a limited or no role in the etiology of endometrial cancer.

Identification of multiple HPV types on spermatozoa from human sperm donors

Human papillomaviruses (HPV) may cause sexually transmitted disease. High-risk types of HPV are involved in the development of cervical cell dysplasia, whereas low-risk types may cause genital condyloma. Despite the association between HPV and cancer, donor sperm need not be tested for HPV according to European regulations. Consequently, the potential health risk of HPV transmission by donor bank sperm has not been elucidated, nor is it known how HPV is associated with sperm. The presence of 35 types of HPV was examined on DNA from semen samples of 188 Danish sperm donors using a sensitive HPV array. To examine whether HPV was associated with the sperm, in situ hybridization were performed with HPV-6, HPV-16 and -18, and HPV-31-specific probes. The prevalence of HPV-positive sperm donors was 16.0% and in 66.7% of these individuals high-risk types of HPV were detected. In 5.3% of sperm donors, two or more HPV types were detected. Among all identified HPV types, 61.9% were high-risk types. In situ hybridization experiments identified HPV genomes particularly protruding from the equatorial segment and the tail of the sperm. Semen samples from more than one in seven healthy Danish donors contain HPV, most of them of high-risk types binding to the equatorial segment of the sperm cell. Most HPV-positive sperm showed decreased staining with DAPI, indicative of reduced content of DNA. Our data demonstrate that oncogenic HPV types are frequent in men.

Evidence of measles virus antigens and RNA in endometrial cancer

OBJECTIVES

To look for an association between the measles virus and endometrial carcinoma, the most frequent cancer of the female genital tract in our area.

STUDY DESIGN

Thirty-six of 49 patients with endometrial carcinoma were studied to detect fingerprints of the measles virus. Immunohistochemistry with the avidin-biotin complex method and in situ hybridization were used to demonstrate the association. The clinicopathological correlations were carried out to support a relationship between the virus and the cancer if any was found.

RESULTS

Twenty-six of the 36 cases (72%) of endometrial cancer showed the presence of measles virus antigens in the tumor cells. Sixteen of 21 cases were positive for measles virus RNA by in situ hybridization. Although type I endometrial carcinoma was more positive for viral particles than type II, type II cancer, when allied with the measles virus, was more often associated with the depth of myometrial invasion and with death from tumor.

CONCLUSIONS

We demonstrate for the first time a link between endometrial cancer and the presence of viral antigens and RNA of the measles virus, although these findings do not necessarily signify a causal relationship between the cancer and the virus.