Advances in endometrial cancer protein biomarkers for use in the clinic

Landscape of Endometrial Cancer: Molecular Mechanisms, Biomarkers, and Target Therapy

Endometrial cancer is one the most prevalent gynecological cancers and, unfortunately, has a poor prognosis due to low response rates to traditional treatments. However, the progress in molecular biology and understanding the genetic mechanisms involved in tumor processes offers valuable information that has led to the current classification that describes four molecular subtypes of endometrial cancer. This review focuses on the molecular mechanisms involved in the pathogenesis of endometrial cancers, such as genetic mutations, defects in the DNA mismatch repair pathway, epigenetic changes, or dysregulation in angiogenic or hormonal signaling pathways. The preclinical genomic and molecular investigations presented allowed for the identification of some molecules that could be used as biomarkers to diagnose, predict, and monitor the progression of endometrial cancer. Besides the therapies known in clinical practice, targeted therapy is described as a new cancer treatment that involves identifying specific molecular targets in tumor cells. By selectively inhibiting these targets, key signaling pathways involved in cancer progression can be disrupted while normal cells are protected. The connection between molecular biomarkers and targeted therapy is vital in the fight against cancer. Ongoing research and clinical trials are exploring the use of standard therapy agents in combination with other treatment strategies like immunotherapy and anti-angiogenesis therapy to improve outcomes and personalize treatment for patients with endometrial cancer. This approach has the potential to transform the management of cancer patients. In conclusion, enhancing molecular tools is essential for stratifying the risk and guiding surgery, adjuvant therapy, and cancer treatment for women with endometrial cancer. In addition, the information from this review may have an essential value in the personalized therapy approach for endometrial cancer to improve the patient's life.

Identification and validation of serum metabolite biomarkers for endometrial cancer diagnosis

Endometrial cancer (EC) stands as the most prevalent gynecological tumor in women worldwide. Notably, differentiation diagnosis of abnormity detected by ultrasound findings (e.g., thickened endometrium or mass in the uterine cavity) is essential and remains challenging in clinical practice. Herein, we identified a metabolic biomarker panel for differentiation diagnosis of EC using machine learning of high-performance serum metabolic fingerprints (SMFs) and validated the biological function. We first recorded the high-performance SMFs of 191 EC and 204 Non-EC subjects via particle-enhanced laser desorption/ionization mass spectrometry (PELDI-MS). Then, we achieved an area-under-the-curve (AUC) of 0.957-0.968 for EC diagnosis through machine learning of high-performance SMFs, outperforming the clinical biomarker of cancer antigen 125 (CA-125, AUC of 0.610-0.684, p < 0.05). Finally, we identified a metabolic biomarker panel of glutamine, glucose, and cholesterol linoleate with an AUC of 0.901-0.902 and validated the biological function in vitro. Therefore, our work would facilitate the development of novel diagnostic biomarkers for EC in clinics.

Deciphering the potential of proteomic-based biomarkers in women's reproductive diseases: empowering precision medicine in gynecology

CONTEXT

Gynecological disorders represent a complex set of malignancies that result from a diverse array of molecular changes affecting the lives of over a million women worldwide. Ovarian, Endometrial, and Cervical cancers, Endometriosis, PCOS are the most prevalent ones that pose a grave threat to women's health. Proteomics has emerged as an invaluable tool for developing novel biomarkers, screening methods, and targeted therapeutic agents for gynecological disorders. Some of these biomarkers have been approved by the FDA, but regrettably, they have a constrained diagnostic accuracy in early-stage diagnosis as all of these biomarkers lack sensitivity and specificity. Lately, high-throughput proteomics technologies have made significant strides, allowing for identification of potential biomarkers with improved sensitivity and specificity. However, limited successes have been shown with translation of these discoveries into clinical practice.

OBJECTIVE

This review aims to provide a comprehensive overview of the current and potential protein biomarkers for gynecological cancers, endometriosis and PCOS, discusses recent advances and challenges, and highlights future directions for the field.

CONCLUSION

We propose that proteomics holds great promise as a powerful tool to revolutionize the fight against female reproductive diseases and can ultimately improve personalized patient outcomes in women's biomedicine.

New therapeutic targets for endometrial cancer: a glimpse into the preclinical sphere

INTRODUCTION

Endometrial cancer (EC) is the only gynecologic malignancy showing increasing trends in incidence and mortality. While standard treatment has been effective primarily for early-stage EC, precision medicine with tailored therapy has revolutionized the management of this disease. Genome sequencing analyses have identified four sub-types of EC. Treatments for primary and metastatic disease can now be tailored more accurately to achieve better oncologic results.

AREAS COVERED

This review provides an overview of the most relevant and updated evidence in the literature regarding EC molecular analysis and its role in risk classification, prognostication, and guidance for tailored and target therapies in early and advanced/metastatic stages. In addition, it provides updated information on optimal surgical management based on molecular classification and highlights key advances and future strategies.

EXPERT OPINION

EC molecular analysis yields the potential of tailoring adjuvant treatment by escalating or deescalating therapy, as shown for POLE-mutated and p53-mutated tumors. Moreover, the expression of specific molecular signatures offers the possibility to employ novel target therapies, such as immune-checkpoint inhibitors that have demonstrated a significant benefit on prognosis. New treatment guidelines are still being established, and ongoing studies are exploring the potential prognostic role of further sub-stratifications of the four molecular classes and treatment options.

Analysis of the characteristics of immune infiltration in endometrial carcinoma and its relationship with prognosis based on bioinformatics

To explore immune-related molecules that affect the prognosis of endometrial carcinoma (EC) using bioinformatic data mining. The expression data related to EC were downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus databases. After differential expression analysis, the intersection with immune related genes in the ImmPort database was used to obtain immune related differentially expressed genes (IRDEGs). The correlation between clinicopathological information and the prognosis of IRDEGs was further analyzed to obtain prognosis related differentially expressed immune genes (PRDEIG). Gene correlation analysis and Gene Set Enrichment Analysis (GSEA) enrichment analysis showed that PRDEIG was enriched in cancer-related functional pathways. We then analyzed the relationship between PRDEIG and immune cell infiltration, and further analyzed the mRNA and protein expression of PRDEIG in EC using TCGA and the human protein expression atlas (THPA) databases. After the intersection of the differential expression analysis results and immune-related genes, 4 IRDEGs were obtained: osteoglycin (OGN), LTBP4, CXCL12, and SPP1. After analyzing the relationship between 4 IRDEGs and clinicopathological parameters and prognosis of patients with EC, revealed that only OGN was not only related to tumor immunity, but also affected the prognosis of patients with EC. Gene correlation and GSEA enrichment of OGN were analyzed. The results showed that OGN was significantly enriched in 6 functional pathways: epithelial mesenchymal transition, KRAS signaling up, myogenesis, UV response, allograft rejection and apical junction. In addition, it was also found that OGN was significantly correlated with a variety of immune cells. The results of TCGA and THPA database showed that the mRNA and protein expression levels of OGN decreased in EC. OGN may affect the epithelial mesenchymal transformation (EMT) of tumor by affecting the infiltration of tumor immune cells.

Upgrading Treatment and Molecular Diagnosis in Endometrial Cancer-Driving New Tools for Endometrial Preservation?

One emerging problem for onco-gynecologists is the incidence of premenopausal patients under 40 years of age diagnosed with stage I Endometrial Cancer (EC) who want to preserve their fertility. Our review aims to define a primary risk assessment that can help fertility experts and onco-gynecologists tailor personalized treatment and fertility-preserving strategies for fertile patients wishing to have children. We confirm that risk factors such as myometrial invasion and The International Federation of Gynecology and Obstetrics (FIGO) staging should be integrated into the novel molecular classification provided by The Cancer Genome Atlas (TCGA). We also corroborate the influence of classical risk factors such as obesity, Polycystic ovarian syndrome (PCOS), and diabetes mellitus to assess fertility outcomes. The fertility preservation options are inadequately discussed with women with a diagnosis of gynecological cancer. A multidisciplinary team of gynecologists, oncologists, and fertility specialists could increase patient satisfaction and improve fertility outcomes. The incidence and death rates of endometrial cancer are rising globally. International guidelines recommend radical hysterectomy and bilateral salpingo-oophorectomy as the standard of care for this cancer; however, fertility-sparing alternatives should be tailored to motivated women of reproductive age, establishing an appropriate cost-benefit balance between childbearing desire and cancer risk. New molecular classifications such as that of TCGA provide a robust supplementary risk assessment tool that can tailor the treatment options to the patient's needs, curtail over- and under-treatment, and contribute to the spread of fertility-preserving strategies.

Application value of Ki67 and serum CA125 in the deep myometrial invasion of endometrial adenocarcinoma

OBJECTIVE

To investigate the application value of Ki67 and serum CA125 in diagnosing the deep myometrial invasion of endometrial adenocarcinoma.

METHODS

This study retrospectively analyzed 80 patients with endometrial adenocarcinoma, who underwent procedure from January 2018 to June 2021 at Senior Department of Obstetrics & Gynecology, the Seventh Medical Center of PLA General Hospital assigned to the Fourth Medical Center. The general clinical data, serum CA125 and Ki67 levels were compared between the superficial muscular infiltration group and the deep myometrial invasion group. We investigated the application value of Ki67 and serum CA125 in diagnosing the deep myometrial invasion of endometrial adenocarcinoma by the ROC curve.

RESULTS

80 patients were retrospectively analyzed, and 53 cases were superficial muscular infiltration, 27 cases were deep myometrial invasion. There was significant difference in age, tumor diameter, lymph node metastasis, Ki67, serum CA125, p53 status, serum CA125 and Ki67 levels between the two groups (p < 0.05). As high as 35% of Ki67 was the optimal cutoff value for predicting DMI in endometrial adenocarcinoma, and the area under ROC curve was 0.691, the sensitivity and specificity of diagnosis were 88.9% and 56.6%. As high as 43.645 U/ml of serum CA125 was the optimal cutoff value for predicting DMI in endometrial adenocarcinoma, and the area under ROC curve was 0.668, the sensitivity and specificity of diagnosis were 40.7% and 92.5%. After combined detection of both, the area under ROC curve was 0.719, and its sensitivity and specificity of diagnosis were 96.3% and 43.4%.

CONCLUSION

Serum CA125 and Ki67 may be used to evaluate DMI in patients with endometrial adenocarcinoma, and the diagnostic value of combination is higher, which provide reference for clinical treatment.

Cervical Fluids Are a Source of Protein Biomarkers for Early, Non-Invasive Endometrial Cancer Diagnosis

BACKGROUND

Abnormal uterine bleeding is the main symptom of endometrial cancer (EC), but it is highly nonspecific. This represents a huge burden for women's health since all women presenting with bleeding will undergo sequential invasive tests, which are avoidable for 90-95% of those women who do not have EC.

METHODS

This study aimed to evaluate the potential of cervical samples collected with five different devices as a source of protein biomarkers to diagnose EC. We evaluated the protein quantity and the proteome composition of five cervical sampling methods.

RESULTS

Samples collected with a Rovers Cervex Brush^® and the HC2 DNA collection device, Digene, were the most suitable samples for EC proteomic studies. Most proteins found in uterine fluids were also detected in both cervical samples. We then conducted a clinical retrospective study to assess the expression of 52 EC-related proteins in 41 patients (22 EC; 19 non-EC), using targeted proteomics. We identified SERPINH1, VIM, TAGLN, PPIA, CSE1L, and CTNNB1 as potential protein biomarkers to discriminate between EC and symptomatic non-EC women with abnormal uterine bleeding in cervical fluids (AUC > 0.8).

CONCLUSIONS

This study opens an avenue for developing non-invasive protein-based EC diagnostic tests, which will improve the standard of care for gynecological patients.

Protein biomarkers in cervicovaginal lavages for detection of endometrial cancer

BACKGROUND

Rates of endometrial cancer (EC) are increasing. For a definitive diagnosis, women undergo various time-consuming and painful medical procedures, such as endometrial biopsy with or without hysteroscopy, and dilation and curettage, which may create a barrier to early detection and treatment, particularly for women with inadequate healthcare access. Thus, there is a need to develop robust EC diagnostics based on non- or minimally-invasive sampling. The objective of this study was to quantify a broad range of immuno-oncology proteins in cervicovaginal lavage (CVL) samples and investigate these proteins as predictive diagnostic biomarkers for EC.

METHODS

One hundred ninety-two women undergoing hysterectomy for benign or malignant indications were enrolled in this cross-sectional study. Classification of women to four disease groups: benign conditions (n = 108), endometrial hyperplasia (n = 18), low-grade endometrioid carcinoma (n = 53) and other EC subtypes (n = 13) was based on histopathology of biopsy samples collected after the surgery. CVL samples were collected in the operating room during the standard-of-care hysterectomy procedure. Concentrations of 72 proteins in CVL samples were evaluated using multiplex immunoassays. Global protein profiles were assessed using principal component and hierarchical clustering analyses. The relationships between protein levels and disease groups and disease severity were determined using Spearman correlation, univariate and multivariate receiver operating characteristics, and logistic regression analyses.

RESULTS

Women with EC and benign conditions exhibited distinctive cervicovaginal protein profiles. Several proteins in CVL samples (e.g., an immune checkpoint protein, TIM-3, growth factors, VEGF, TGF-α, and an anti-inflammatory cytokine, IL-10) discriminated EC from benign conditions, particularly, when tested in combinations with CA19-9, CA125, eotaxin, G-CSF, IL-6, MCP-1, MDC, MCP-3 and TRAIL (sensitivity of 86.1% and specificity of 87.9%). Furthermore, specific biomarkers (e.g., TIM-3, VEGF, TGF-α, TRAIL, MCP-3, IL-15, PD-L2, SCF) associated with histopathological tumor characteristics, including histological type and grade, tumor size, presence and depth of myometrial invasion or mismatch repair protein status, implying their potential utility for disease prognosis or monitoring therapies.

CONCLUSIONS

This proof-of-principle study demonstrated that cervicovaginal sampling coupled with multiplex immunoassay technology can offer a minimally to non-invasive method for EC detection.

Expression and clinical significance of CXCL17 and GPR35 in endometrial carcinoma

Endometrial carcinoma is one of the most common gynecologic malignancies. CXCL17-CXCR8 (GPR35) axis is reported to play an indispensability role in tumors. Our purpose is to screen possible prognostic and immune-related factors in endometrial carcinoma by detecting the mRNA and protein expression of CXCL17 and CXCR8. We use the qRT-PCR method to test the mRNA expression of CXCL17 and CXCR8 in 35 pairs of endometrial carcinoma and adjacent tissue. The protein expression of CXCL17 and CXCR8 in 30 cases of normal proliferative endometrium, 30 cases of endometrial atypical hyperplasia and 50 cases of endometrial carcinoma was detected by tissue microarray immunohistochemistry. There was no significant difference in the positive expression rate between endometrial adenocarcinoma tissue and endometrial atypical hyperplasia tissue (P > 0.05). But significantly better than normal proliferative tissue (P < 0.001). Correlation analysis of CXCR8 and CXCL17 in endometrial carcinoma showed a positive correlation (r = 0.9123, P < 0.0001). For patients with endometrial cancer, the overall survival (OS) of patients with high CXCL17 expression was significantly higher than that low CXCL17 expression (log-rank test, P < 0.0001), whereas CXCR8 had no statistical significance. But the expression of CXCR8 is an independent prognostic factor of OS in endometrial carcinoma patients. Our study showed that CXCL17 and CXCR8 may be involved in the occurrence and development of endometrial cancer. High expression of CXCL17 may be used as a biomarker for predicting survival. Because CXCL17 and CXCL18 are related to lymphocytes and immune regulation, they are expected to become potential targets for immunotherapy.

Associations between Genetically Predicted Circulating Protein Concentrations and Endometrial Cancer Risk

Simple Summary

Endometrial cancer is the leading female reproductive tract cancer in developed countries. Discovering new biomarkers is critical for understanding the etiology this cancer and identifying women with a higher risk of this cancer from the general population. Several blood protein biomarkers have been linked to endometrial cancer in previous studies, but these studies have assessed only a limited number of biomarkers usually among a small number of participants. The current study aimed at identifying novel circulating protein biomarkers of endometrial cancer by using the largest available dataset to date. Our finding suggested nine proteins to be associated with endometrial cancer risk, and five of the identified associations showed suggestive associations with risk of non-endometrioid EC, a much more lethal subtype. If validated by additional studies, our findings may contribute to understanding the pathogenesis of endometrial tumor development and facilitating the risk assessment of endometrial cancer.

Abstract

Endometrial cancer (EC) is the leading female reproductive tract malignancy in developed countries. Currently, genome-wide association studies (GWAS) have identified 17 risk loci for EC. To identify novel EC-associated proteins, we used previously reported protein quantitative trait loci for 1434 plasma proteins as instruments to evaluate associations between genetically predicted circulating protein concentrations and EC risk. We studied 12,906 cases and 108,979 controls of European descent included in the Endometrial Cancer Association Consortium, the Epidemiology of Endometrial Cancer Consortium, and the UK Biobank. We observed associations between genetically predicted concentrations of nine proteins and EC risk at a false discovery rate of <0.05 (p-values range from 1.14 × 10⁻¹⁰ to 3.04 × 10⁻⁴). Except for vascular cell adhesion protein 1, all other identified proteins were independent from known EC risk variants identified in EC GWAS. The respective odds ratios (95% confidence intervals) per one standard deviation increase in genetically predicted circulating protein concentrations were 1.21 (1.13, 1.30) for DNA repair protein RAD51 homolog 4, 1.27 (1.14, 1.42) for desmoglein-2, 1.14 (1.07, 1.22) for MHC class I polypeptide-related sequence B, 1.05 (1.02, 1.08) for histo-blood group ABO system transferase, 0.77 (0.68, 0.89) for intestinal-type alkaline phosphatase, 0.82 (0.74, 0.91) for carbohydrate sulfotransferase 15, 1.07 (1.03, 1.11) for D-glucuronyl C5-epimerase, and 1.07 (1.03, 1.10) for CD209 antigen. In conclusion, we identified nine potential EC-associated proteins. If validated by additional studies, our findings may contribute to understanding the pathogenesis of endometrial tumor development and identifying women at high risk of EC along with other EC risk factors and biomarkers.

Dermatopontin as a potential pathogenic factor in endometrial cancer

The present study aimed to determine the differential expression profiles of proteins in endometrial carcinoma and to screen the proteins associated with the occurrence and development of endometrial cancer (EC). In total, 15 samples of human EC and paracancerous tissues were selected for proteomic analysis using a label-free quantification method based on liquid chromatography-tandem mass spectrometry. The differential proteins were analysed using bioinformatics and verified using reverse transcription-quantitative PCR (RT-qPCR) and western blotting. Finally, the expression of differential proteins in 75 endometrial carcinoma samples and 30 normal endometrial tissue samples were detected using immunohistochemical staining, and the associations between differential protein expression and clinicopathological features were analysed. In total, 579 up-regulated proteins and 346 down-regulated proteins were identified between the two groups and seven proteins with the most significant differences were selected; these proteins included interferon-induced protein with tetratricopeptide repeats 3, poly(ADP-ribose) polymerase family member 9, solute carrier family 34 member 2, cytochrome b5 reductase 1, protein tyrosine phosphatase non-receptor type 1, dermatopontin (DPT) and secretory leukocyte peptidase inhibitor. RT-qPCR and western blotting showed that DPT expression was down-regulated (P<0.001), which was consistent with the mass spectrometry results. The immunohistochemical staining results showed that the positive expression of DPT in EC and normal endometrial tissues was statistically significant (P<0.001). The positive expression of DPT was significantly decreased in poorly differentiated, late stage, lymph node metastasis and myometrial invasion depth ≥1/2 samples (P<0.05). DPT expression was significantly lower in EC, which might play role in the pathogenesis of EC.

Prognostic Biomarkers in Endometrial Cancer: A Systematic Review and Meta-Analysis

Endometrial cancer (EC) is the sixth most common cancer in women worldwide and its mortality is directly associated with the presence of poor prognostic factors driving tumor recurrence. Stratification systems are based on few molecular, and mostly clinical and pathological parameters, but these systems remain inaccurate. Therefore, identifying prognostic EC biomarkers is crucial for improving risk assessment pre- and postoperatively and to guide treatment decisions. This systematic review gathers all protein biomarkers associated with clinical prognostic factors of EC, recurrence and survival. Relevant studies were identified by searching the PubMed database from 1991 to February 2020. A total number of 398 studies matched our criteria, which compiled 255 proteins associated with the prognosis of EC. MUC16, ESR1, PGR, TP53, WFDC2, MKI67, ERBB2, L1CAM, CDH1, PTEN and MMR proteins are the most validated biomarkers. On the basis of our meta-analysis ESR1, TP53 and WFDC2 showed potential usefulness for predicting overall survival in EC. Limitations of the published studies in terms of appropriate study design, lack of high-throughput measurements, and statistical deficiencies are highlighted, and new approaches and perspectives for the identification and validation of clinically valuable EC prognostic biomarkers are discussed.

Identification of core genes in the progression of endometrial cancer and cancer cell-derived exosomes by an integrative analysis

Endometrial cancer is one of the most prevalent tumors of the female reproductive system causing serious health effects to women worldwide. Although numerous studies, including analysis of gene expression profile and cellular microenvironment have been reported in this field, pathogenesis of this disease remains unclear. In this study, we performed a system bioinformatics analysis of endometrial cancer using the Gene Expression Omnibus (GEO) datasets (GSE17025, GSE63678, and GSE115810) to identify the core genes. In addition, exosomes derived from endometrial cancer cells were also isolated and identified. First, we analyzed the differentially expressed genes (DEGs) between endometrial cancer tissues and normal tissues in clinic samples. We found that HAND2-AS1, PEG3, OGN, SFRP4, and OSR2 were co-expressed across all 3 datasets. Pathways analysis showed that several pathways associated with endometrial cancer, including "p53 signaling pathway", "Glutathione metabolism", "Cell cycle", and etc. Next, we selected DEGs with highly significant fold change and co-expressed across the 3 datasets and validated them in the TCGA database using Gene Expression Profiling Interactive Analysis (GEPIA). Finally, we performed a survival analysis and identified four genes (TOP2A, ASPM, EFEMP1, and FOXL2) that play key roles in endometrial cancer. We found up-regulation of TOP2A and ASPM in endometrial cancer tissues or cells, while EFEMP1 and FOXL2 were down-regulated. Furthermore, we isolated exosomes from the culturing supernatants of endometrial cancer cells (Ishikawa and HEC-1-A) and found that miR-133a, which regulates expression of FOXL2, were present in exosomes and that they could be delivered to normal endometrial cells. The common DEGs, pathways, and exosomal miRNAs identified in this study might play an important role in progression as well as diagnosis of endometrial cancer. In conclusion, our results provide insights into the pathogenesis and risk assessment of endometrial cancer. Even so, further studies are required to elucidate on the precise mechanism of action of these genes in endometrial cancer.

Proteomic Biomarkers for the Detection of Endometrial Cancer

Endometrial cancer is the leading gynaecological malignancy in the western world and its incidence is rising in tandem with the global epidemic of obesity. Early diagnosis is key to improving survival, which at 5 years is less than 20% in advanced disease and over 90% in early-stage disease. As yet, there are no validated biological markers for its early detection. Advances in high-throughput technologies and machine learning techniques now offer unique and promising perspectives for biomarker discovery, especially through the integration of genomic, transcriptomic, proteomic, metabolomic and imaging data. Because the proteome closely mirrors the dynamic state of cells, tissues and organisms, proteomics has great potential to deliver clinically relevant biomarkers for cancer diagnosis. In this review, we present the current progress in endometrial cancer diagnostic biomarker discovery using proteomics. We describe the various mass spectrometry-based approaches and highlight the challenges inherent in biomarker discovery studies. We suggest novel strategies for endometrial cancer detection exploiting biologically important protein biomarkers and set the scene for future directions in endometrial cancer biomarker research.

New perspectives on screening and early detection of endometrial cancer

Due to the anatomical continuity of the uterine cavity with the cervix, genomic exploitation of material from routine Pap smears and other noninvasive sampling methods represent a unique opportunity to detect signs of disease using biological material shed from the upper genital tract. Recent research findings offer a promising perspective in the detection of endometrial cancer, but certain questions need to be addressed in order to accelerate the implementation of novel technologies in a routine screening or clinical setting. We discuss here new perspectives on detection of endometrial cancer using genomic and other biomarkers in minimally invasive sampling methods with a special focus on public health classic screening criteria, highlighting current gaps in knowledge.

Identification of key transcription factors in endometrial cancer by systems bioinformatics analysis

Endometrial cancer (EC) is one of the most common malignant diseases worldwide. Although many studies have been performed on EC, a systems analysis between transcription factors (TFs) and EC relationship remains poorly characterized. Here, we present a systems bioinformatics analysis of TFs in EC patient samples to identify key TFs in EC. First, dysregulated and survival-related TFs were identified in EC using data from The Cancer Genome Atlas database and Gene Expression Omnibus. Second, we investigated the mechanisms of dysregulated TFs and tested whether their expression is correlated with prognosis of EC. Finally, we addressed new perspectives in EC biomarker research, including comprehensive knowledge of previously suggested candidate biomarkers in conjunction with novel mass spectrometry-based proteomic technologies with enhanced sensitivity and specificity not yet applied to EC studies, enabling a directed clinical perspective of the study design. Our study identified three promising TFs, E2F1, HMGA1, and PGR, which closely correlate with EC. Although treatments targeting TFs are not always efficient, these TFs may be useful as biomarkers for the diagnosis and prognosis of EC. Furthermore, we found that these dysregulated TFs and their target genes are primarily involved in the cell cycle and may promote endometrial carcinoma occurrence and development. Using integrated bioinformatic analysis, we identified candidate genes and pathways in EC, which could improve our understanding of the etiology and underlying molecular events of EC. Furthermore, these candidate genes and pathways could be therapeutic targets for EC.

Anti-Müllerian Hormone Expression in Endometrial Cancer Tissue

Anti-Müllerian hormone (AMH) is a commonly known factor secreted by Sertoli cells, responsible for regression of the Müllerian ducts in male fetuses. AMH has also other functions in humans. In vivo and in vitro studies have shown that AMH inhibits cell cycle and induces apoptosis in cancers with AMH receptors. The aim of the study was to assess whether the tissue of pre-cancerous states of endometrium (PCS) and various histopathologic types of endometrial cancer (EC) exhibit the presence of AMH. We aimed to investigate whether the potential presence of the protein concerns menopausal women or those regularly menstruating, and whether is related to cancers with a good or a bad prognosis, as well as what other factors may influence AMH expression. The undertaken analysis was carried out on tissues retrieved from 232 women who underwent surgical treatment for PCS and EC. Tissues were prepared for immunohistochemical assessment with the use of a tissue microarrays method. AMH expression was confirmed in 23 patients with well differentiated endometrioid adenocarcinoma (G1), moderately differentiated endometrioid adenocarcinoma (G2), clear cell carcinoma (CCA) and nonatypical hyperplasia. AMH was not found in EC tissues in regularly menstruating women. An appropriately long mean period of breastfeeding in line with a prolonged period of hormonal activity had a positive effect on AMH expression. Our results may suggest that AMH is a factor which protects the organism against cancer, and should be further investigated as a potential prognosis marker and a therapeutic agent.

HOXB9 promotes endometrial cancer progression by targeting E2F3

HOXB9, as a HOX family transcription factor, playing a significant role in embryonic development and cancer progression. However, the function of HOXB9 and its precise mechanism in regulating endometrial cancer progression remains unknown. Here, we demonstrated that the expression of HOXB9 was increased in endometrial cancer, and associated with histological grade and lymph node metastasis. In addition, elevated HOXB9 predicts a poor prognosis in endometrial cancer patients. Interestingly, bioinformatics analysis of TCGA cancer database showed that HOXB9 expression is positively correlated with E2F3 expression. Moreover, HOXB9 promoted E2F3 expression by directly targeting to its promoter. Furthermore, we found that knocking down E2F3 abolished the ability of HOXB9 in enhancing cell migration. Taken together, for the first, we demonstrated the function and mechanism of HOXB9 in regulating endometrial cancer progression, and indicated HOXB9 may be a novel prognostic marker of endometrial cancer.