An update of the classical Bokhman's dualistic model of endometrial cancer

A comprehensive analysis of immunotherapy in advanced endometrial cancer (Review)

The morbidity and mortality rates of endometrial cancer (EC) are increasing yearly. Early-stage EC can be effectively treated through surgery or surgery combined with radiotherapy and chemotherapy. Advanced and recurrent EC is treated with chemotherapy and comprehensive treatment; however, the prognosis for patients at this disease stage is poor. Consequently, novel and effective treatment strategies are urgently required for these patients. Breakthrough progress has been made with the use of immunosuppressants in the treatment of EC, which have been included in treatment guidelines. In the present review, the etiology and classification of EC was outlined and the relevant scientific basis for the application of immunosuppressants in advanced and recurrent EC was discussed. The relevant published and ongoing clinical trials are also summarized. As such, the present review aimed to provide a scientific summary of immunotherapy of EC.

Models including preoperative plasma levels of angiogenic factors, leptin and IL-8 as potential biomarkers of endometrial cancer

Background

The diversity of endometrial cancer (EC) dictates the need for precise early diagnosis and pre-operative stratification to select treatment options appropriately. Non-invasive biomarkers invaluably assist clinicians in managing patients in daily clinical practice. Currently, there are no validated diagnostic or prognostic biomarkers for EC that could accurately predict the presence and extent of the disease.

Methods

Our study analyzed 202 patients, of whom 91 were diagnosed with EC and 111 were control patients with the benign gynecological disease. Using Luminex xMAP™ multiplexing technology, we measured the pre-operative plasma concentrations of six previously selected angiogenic factors - leptin, IL-8, sTie-2, follistatin, neuropilin-1, and G-CSF. Besides basic statistical methods, we used a machine-learning algorithm to create a robust diagnostic model based on the plasma concentration of tested angiogenic factors.

Results

The plasma levels of leptin were significantly higher in EC patients than in control patients. Leptin was higher in type 1 EC patients versus control patients, and IL-8 was higher in type 2 EC versus control patients, particularly in poorly differentiated endometrioid EC grade 3. IL-8 plasma levels were significantly higher in EC patients with lymphovascular or myometrial invasion. Among univariate models, the model based on leptin reached the best results on both training and test datasets. A combination of age, IL-8, leptin and G-CSF was determined as the most important feature for the multivariate model, with ROC AUC 0.94 on training and 0.81 on the test dataset. The model utilizing a combination of all six AFs, BMI and age reached a ROC AUC of 0.89 on both the training and test dataset, strongly indicating the capability for predicting the risk of EC even on unseen data.

Conclusion

According to our results, measuring plasma concentrations of angiogenic factors could, provided they are confirmed in a multicentre validation study, represent an important supplementary diagnostic tool for early detection and prognostic characterization of EC, which could guide the decision-making regarding the extent of treatment.

Biological Activity of fac-[Re(CO)3(phen)(aspirin)], fac-[Re(CO)3(phen)(indomethacin)] and Their Original Counterparts against Ishikawa and HEC-1A Endometrial Cancer Cells

Nonsteroidal anti-inflammatory drugs (NSAIDs) are inhibitors of cyclooxygenase enzyme (COX) and were found to have positive effects in reducing the risk of developing gynecological cancers. However, long-term administration of NSAIDs carries the risk of various side effects, including those in the digestive and circulatory systems. Therefore, there is a constant need to develop new NSAID derivatives. In this work, we investigated rhenium NSAIDs, comparing their effects on endometrial cancer cells with original NSAIDs, demonstrating the high activity of aspirin and indomethacin derivatives. The cytotoxic activity of rhenium derivatives against the Ishikawa and HEC-1A cancer cell lines was higher than that of the original NSAIDs. The IC50 after 24-h incubation of Ishikawa and HEC-1A were 188.06 µM and 394.06 µM for rhenium aspirin and 228.6 µM and 1459.3 µM for rhenium indomethacin, respectively. At the same time, IC50 of aspirin and indomethacin were 10,024.42 µM and 3295.3 µM for Ishikawa, and 27,255.8 µM and 5489.3 µM for HEC-1A, respectively. Moreover, these derivatives were found to inhibit the proliferation of both cell lines in a time- and state-dependent manner. The Ishikawa cell proliferation was strongly inhibited by rhenium aspirin and rhenium indomethacin after 72-h incubation (*** = p < 0.001), while the HEC-1A proliferation was inhibited by the same agents already after 24-h incubation (*** = p < 0.001). Furthermore, the ROS level in the mitochondria of the tested cells generated in the presence of rhenium derivatives was higher than the original NSAIDs. That was associated with rhenium indomethacin exclusively, which had a significant effect (*** = p < 0.001) on both Ishikawa and HEC-1A cancer cells. Rhenium aspirin had a significant effect (*** = p < 0.001) on the mitochondrial ROS level of Ishikawa cells only. Overall, the research revealed a high potential of the rhenium derivatives of aspirin and indomethacin against endometrial cancer cells compared with the original NSAIDs.

Current Approaches to the Management of Patients with Endometrial Cancer

Simple Summary

New data, the development of new methods of treatment and management and the rising incidence of endometrial cancer require constant reviewing, in order to inform healthcare professionals about the current approaches to endometrial cancer. This review aims to present old, new and emerging perspectives in the management of endometrial cancer and evaluate the existing therapeutic strategies, by assessing the different surgical routes, the position of adjuvant therapies in the treatment of endometrial cancer and the implementation of SLNB. Upon reviewing literature data, it became clear that minimally invasive surgery is becoming gradually the preferred route of surgery, whereas SLNB is gaining more ground and could yield important information about the management needed in low-risk and high-risk endometrial cancer.

Abstract

The incidence of endometrial cancer (EC) is rising and healthcare professionals need to be informed about the latest data on the constant developments in the field of its management. With particular interest in the classification and management of EC, we surveyed current literature, national and international data, and guidelines, as well as the latest studies to present the most recent data regarding the management of EC. It became evident that despite the consensus on low-risk EC, there are still controversies surrounding the management of high-risk EC, especially regarding the role of sentinel lymph node biopsy (SLNB). Our aim is to present the old and new perspectives in the management of EC, the different available surgical routes, the possible desire for fertility preservation, the role of adjuvant therapies and the focus on the advantages and the limitations of the implementation of SLNB in therapeutic strategies. It became evident throughout our search and based on literature data that minimally invasive surgery (MIS) leads to satisfying outcomes, thus becoming gradually the preferred route of surgery, while SLNB could provide essential information and guidance about the overall management needed in cases of both low-risk and high-risk EC.

Bone Marrow-Derived Cells in Endometrial Cancer Pathogenesis: Insights from Breast Cancer

Endometrial cancer is the most common gynecological cancer, representing 3.5% of all new cancer cases in the United States. Abnormal stem cell-like cells, referred to as cancer stem cells (CSCs), reside in the endometrium and possess the capacity to self-renew and differentiate into cancer progenitors, leading to tumor progression. Herein we review the role of the endometrial microenvironment and sex hormone signaling in sustaining EC progenitors and potentially promoting dormancy, a cellular state characterized by cell cycle quiescence and resistance to conventional treatments. We offer perspective on mechanisms by which bone marrow-derived cells (BMDCs) within the endometrial microenvironment could promote endometrial CSC (eCSC) survival and/or dormancy. Our perspective relies on the well-established example of another sex hormone-driven cancer, breast cancer, in which the BM microenvironment plays a crucial role in acquisition of CSC phenotype and dormancy. Our previous studies demonstrate that BMDCs migrate to the endometrium and express sex hormone (estrogen and progesterone) receptors. Whether the BM is a source of eCSCs is unknown; alternatively, crosstalk between BMDCs and CSCs within the endometrial microenvironment could be an additional mechanism supporting eCSCs and tumorigenesis. Elucidating these mechanisms will provide avenues to develop novel therapeutic interventions for EC.

Clear Cell Carcinoma of the Endometrium: Evaluation of Prognostic Parameters in 27 Cases

Objective

Clear cell carcinoma (CCC) of the endometrium is an uncommon yet aggressive tumor. Few cohort studies are reporting the overall survival time of CCC patients. This study aimed to retrospectively analyze the clinicopathologic features, molecular characteristics and survival data of 27 endometrial CCC patients to improve the understanding of CCC.

Methods

The clinicopathologic features, molecular characteristics and survival data total of 27 CCC patients admitted to the BBMU affiliated hospital (Anhui, China) between January 2005 and December 2018 were retrospectively analyzed. Kaplan-Meier method was used to analyze the prognosis-related factors.

Results

The median age of the patients was 60 years (range; 39 to 81 years). The average tumor size was 3.8 cm (range; 0.8 to 13.0cm). Myometrial infiltration greater than 50% was reported in 55.6% of the patients, while the Ki-67 index greater than 50% was reported in 70.4% of the patients. The patients’ FIGO (2009) surgical stages were as follows: 18 I, 3 II, 4 III, and 2 IV. Besides, 7 (25.6%) patients had lymphovascular invasion, 3 (11.1%) patients with distant metastasis, including 1 patient with bone metastasis, and 2 with liver metastasis. Adjuvant treatment included 7 with chemotherapy alone, 9 with radiotherapy alone, and 9 with both radiotherapy and chemotherapy. The median overall survival time from the time of CCC diagnosis was 56 months. ER and PR showed negative expression and P16 showed patchy immunostaining. 18 (63%) cases showed Napsin A positive expression. Loss of MSH2, MSH6 and PTEN were seen in 5, 4 and 7 cases respectively. All cases showed HER-2/nue negative expression.

Conclusion

CCC is a rare and invasive tumor. Age of diagnosis, FIGO stage, tumor size, myometrial infiltration, lymphovascular invasion, distant metastasis, Ki-67 index and P53 expression are important indicators to evaluate patient’s prognosis (P = 0.048, P < 0.001, P = 0.016, P = 0.043, P = 0.001, P < 0.001, P = 0.026, and P = 0.007, respectively). CCC has a worse prognosis than endometrioid carcinoma (P = 0.002), and there is no significant difference when compared with uterine papillary serous carcinoma (P = 0.155).

What Has Changed in the Management of Uterine Serous Carcinomas? Two Decades of Experience

Uterine serous carcinoma accounts for 3-10% of endometrial cancers, but it is the most lethal histopathological subtype. The molecular characterization of endometrial carcinomas has allowed novel therapeutic approaches for these patients. We undertook a retrospective analysis of patients with uterine serous carcinomas treated in our hospital within the last two decades to identify possible changes in their management. The patients and their characteristics were evenly distributed across the two decades. Treatment modalities did not change significantly throughout this period. After adjuvant treatment, patients' median disease-free survival was 42.07 months (95% CI: 20.28-63.85), and it did not differ significantly between the two decades (p = 0.059). The median overall survival was 47.51 months (95% Cl: 32.18-62.83), and it significantly favored the first decade's patients (p = 0.024). In patients with de novo metastatic or recurrent disease, median progression-free survival was 7.8 months (95% Cl: 5.81-9.93), whereas both the median progression-free survival and the median overall survival of these patients did not show any significant improvement during the examined time period. Overall, the results of our study explore the minor changes in respect of uterine serous carcinoma's treatment over the last two decades, which are reflected in the survival outcomes of these patients and consequently underline the critical need for therapeutic advances in the near future.

Metalloproteinases in Endometrial Cancer-Are They Worth Measuring?

Endometrial cancer is one of the most common gynecological malignancies, yet the molecular mechanisms that lead to tumor development and progression are still not fully established. Matrix metalloproteinases (MMPs) are a group of enzymes that play an important role in carcinogenesis. They are proteases involved in the degradation of the extracellular matrix (ECM) that surrounds the tumor and the affected tissue allows cell detachment from the primary tumor causing local invasion and metastasis formation. Recent investigations demonstrate significantly increased metalloproteinase and metalloproteinase inhibitor levels in patients with endometrial cancer compared to those with normal endometrium. In this review, we aim to show their clinical significance and possible use in the diagnosis and treatment of patients with endometrial cancer. We have critically summarized and reviewed the research on the role of MMPs in endometrial cancer.

Research progress of PARP inhibitor monotherapy and combination therapy for endometrial cancer

Endometrial cancer is one of the three most common malignant tumors in the female reproductive system. Advanced and recurrent endometrial cancers have poor prognoses and lack effective treatments. Poly(ADP-ribose) polymerase (PARP) inhibitors have been applied to many different types of tumors, and they can selectively kill tumor cells that are defective in homologous recombination repair. Endometrial cancer is characterized by mutations in homologous recombination repair genes; accordingly, PARP inhibitors have achieved positive results in off-label treatments of endometrial cancer cases. Clinical trials of PARP inhibitors as monotherapies and within combination therapies for endometrial cancer are ongoing. For this review, we searched PubMed with "endometrial cancer" and "PARP inhibitor" as keywords, and we used "olaparib", "rucaparib", "niraparib" and "talazoparib" as search terms in clinicaltrials.gov for ongoing trials. The literature search ended in October 2020, and only English-language publications were selected. Multiple studies confirm that PARP inhibitors play an important role in killing tumor cells with defects in homologous recombination repair. Its combination with immune checkpoint inhibitors, PI3K/AKT/mTOR pathway inhibitors, cell cycle checkpoint inhibitors, and other drugs can improve the treatment of endometrial cancer.

Prognostic impact of tumor budding in endometrial carcinoma within distinct molecular subgroups

Tumor budding is a robust prognostic parameter in several tumor entities but is rarely investigated in endometrial carcinoma. We applied the recently standardized counting method from the International Tumor Budding Consensus Conference for colorectal cancer (ITBCC) on a cohort of 255 endometrial carcinomas with known molecular profiles according to The Cancer Genome Atlas (TCGA) subgroups. Our investigation aims to clarify the potential prognostic role of tumor budding in endometrial carcinoma in contrast to other known prognostic factors, including molecular factors. In addition, the microcystic elongated and fragmented (MELF) pattern and tumor budding were compared with respect to their potential as markers for epithelial-mesenchymal transition (EMT). Tumor budding was found in n = 67 (26.3%) tumors, with a very low mean of 0.7 buds per ×20 HE field. Tumor budding was significantly associated with depth of invasion, nodal status, lymphatic invasion (each p < 0.001), grading (p = 0.004), and vascular invasion (p = 0.01). Tumor budding showed moderate inter-observer-variability with prognostic stratification irrespective of the observer (κ-value = 0.448). In multivariate analysis, tumor budding served as a significant independent prognosticator for worse outcomes in overall and recurrence-free survival (HR 2.376 and 2.736, p < 0.001), but not when the TCGA subgroups entered into the analysis. In consequence, dependency had to be clarified in the subgroup analysis for Polymerase E mutated (POLEmut), mismatch repair deficient (MMRdef), nonspecific mutation profile (NSMP), and P53 aberrant (P53abn) endometrial carcinomas. A particular impact was identified in the intermediate prognostic groups of NSMP and MMRdef carcinomas. Tumor budding outperformed the MELF pattern in single and combined prognostic information. In conclusion, the presence of tumor budding alone is a promising, robust, and easy-to-apply prognostic parameter in endometrial carcinoma. In a morpho-molecular approach, it exerts its prognostic potential in the most clinically relevant subgroups of endometrial carcinoma and serves as a good biomarker for EMT.

PARP Inhibitors in Endometrial Cancer: Current Status and Perspectives

Advanced, recurrent and metastatic endometrial cancer (EC) has a dismal prognosis due to poor response rates to conventional treatments. In the era of precision medicine, the improved understanding of cancer genetics and molecular biology has led to the development of targeted therapies, such as poly (ADP-ribose) polymerase (PARP) inhibitors. This class of drugs that inhibit PARP enzymes has been investigated in many different types of tumors and its use in the treatment of gynecological malignancies has rapidly increased over the past few years. Data from several clinical trials showed that PARP inhibitors have a beneficial role in cancers with a defect in the homologous DNA recombination system, regardless of the BRCA mutational status. Since EC frequently shows mutations in PTEN and TP53 genes, indirectly involved in the homologous DNA recombination pathway, several in vivo and in vitro studies investigated the efficacy of PARP inhibitors in EC, showing promising results. This review will discuss the use of PARP inhibitors in endometrial cancer, summarizing data from preclinical studies and providing an overview of the ongoing trials, with a special focus on the development of combined treatment strategies with PARP inhibitors and immune checkpoint inhibitors.

Immune Checkpoint Inhibitors: A Promising Choice for Endometrial Cancer Patients?

Although around 80% of endometrial cancers are diagnosed at early stages and present with a 5-year survival rate exceeding 95%, patients with advanced and recurrent disease show a poor prognosis and low response rates to standard chemotherapy. In the era of targeted therapy, the great advances in the understanding of programmed death-ligand 1 (PD-L1) upregulation in cancer cells, which is responsible for tumor immune escape, have contributed to the increasing interest in immune checkpoint inhibitors as a promising strategy for the treatment of several refractory solid malignancies, including endometrial cancer. Several clinical trials have investigated the efficacy and safety of immune checkpoint inhibitors in endometrial cancer, which already led to the approval of the anti-programmed cell death protein 1 (anti-PD-1) antibody pembrolizumab as a satisfactory alternative for selected patients with unresectable or metastatic disease. As the future of cancer treatment will probably rely on combination therapy strategies, currently, innovative ongoing trials are exploring the potential role of immune checkpoint inhibitors associated with chemotherapy, radiotherapy, and other targeted therapies. Moreover, further research is warranted to discover new specific biomarkers that can accurately predict the response to immunotherapy.

Checkpoint inhibitors in endometrial cancer: preclinical rationale and clinical activity

CONTEXT

Treatment of advanced and recurrent endometrial cancer (EC) is still an unmet need for oncologists and gynecologic oncologists. The Cancer Genome Atlas Research Network (TCGA) recently provided a new genomic classification, dividing EC in four subgroups. Two types of EC, the polymerase epsilon (POLE)-ultra-mutated and the microsatellite instability-hyper-mutated (MSI-H), are characterized by a high mutation rate providing the rationale for a potential activity of checkpoint inhibitors.

MATERIALS AND METHODS

We analyzed all available evidence supporting the role of tumor microenvironment (TME) in EC development and the therapeutic implications offered by immune checkpoint inhibitors in this setting. We performed a review on Pubmed with Mesh keywords 'endometrial cancer' and the name of each checkpoint inhibitor discussed in the article. The same search was operated on clinicaltrial.gov to identify ongoing clinical trials exploring PD-1/PD-L1 and CTLA-4 axis in EC, particularly focusing on POLE-ultra-muted and MSI-H cancer types.

RESULTS

POLE-ultra-mutated and MSI-H ECs showed an active TME expressing high number of neo-antigens and an elevated amount of tumor infiltrating lymphocytes (TILs). Preliminary results from a phase-1 clinical trial (KEYNOTE-028) demonstrated antitumor activity of Pembrolizumab in EC. Moreover, both Pembrolizumab and Nivolumab reported durable clinical responses in POLE-ultra-mutated patients.

CONCLUSIONS

Immune checkpoint inhibitors are an attractive option in POLE-ultra-mutated and MSI-H ECs. Future investigations in these subgroups include combinations of checkpoints inhibitors with chemotherapy and small tyrosine kinase inhibitors (TKIs) to enhance a more robust intra-tumoral immune response.