Unique Molecular Features in High-Risk Histology Endometrial Cancers

A review of basic to clinical targeted therapy and immunotherapy in uterine serous cancer

Uterine serous carcinomas show more frequent mutations of TP53, FBXW7, PIK3CA, and PP2R1A. Furthermore, cyclin-dependent kinase, human epidermal growth factor receptor 2, phosphatidylinositol 3-kinase/protein kinase B, and mammalian target of rapamycin signaling pathways are involved in uterine serous carcinoma progression. However, most patients with uterine serous carcinoma develop chemoresistance to paclitaxel and carboplatin. Moreover, uterine serous carcinoma shows immunosuppressive microenvironment with lower frequency of microsatellite instability. However, some clinical trials of human epidermal growth factor receptor 2/neu and WEE1 targeted therapies showed good effects in prolonging the survival in patients with uterine serous carcinoma. More effective targeted therapies and immunotherapies need to be developed in recurrent uterine serous carcinomas.

Looking beyond carboplatin and paclitaxel for the treatment of advanced/recurrent endometrial cancer

Endometrial cancer incidence and mortality are rising among all ethnic groups. Carboplatin plus paclitaxel is the established frontline treatment for advanced/recurrent disease; however, subsequent treatment with traditional cytotoxic chemotherapy is challenging. The molecular characterization of endometrial cancer has provided important insights into the biological drivers of carcinogenesis, which has allowed for the development of newer precision immunotherapies and targeted therapies, including pembrolizumab, dostarlimab, and lenvatinib. Until recently, platinum rechallenge was often considered at the time of recurrence, given the lack of other available therapeutic options; however, "platinum sensitivity" in endometrial cancer is subjective and largely based on expert opinion and/or practitioner experience. Small retrospective studies have tried to provide guidance on the utility of platinum rechallenge, but they are limited by variable patient characteristics and small sample sizes. The applicability of these retrospective studies to contemporary clinical practice is difficult in the setting of changing patient demographics, a better understanding of endometrial cancer drivers, and the recent approvals of immune checkpoint inhibitors and the combination of lenvatinib plus pembrolizumab in the second-line setting. The primary focus of this review is to distill the available data regarding platinum-doublet chemotherapy rechallenge and highlight recent pivotal developments in endometrial cancer treatment, as well as future directions.

Comparative transcriptome analysis between patient and endometrial cancer cell lines to determine common signaling pathways and markers linked to cancer progression

The rising incidence and mortality of endometrial cancer (EC) in the United States calls for an improved understanding of the disease's progression. Current methodologies for diagnosis and treatment rely on the use of cell lines as models for tumor biology. However, due to inherent heterogeneity and differential growing environments between cell lines and tumors, these comparative studies have found little parallels in molecular signatures. As a consequence, the development and discovery of preclinical models and reliable drug targets are delayed. In this study, we established transcriptome parallels between cell lines and tumors from The Cancer Genome Atlas (TCGA) with the use of optimized normalization methods. We identified genes and signaling pathways associated with regulating the transformation and progression of EC. Specifically, the LXR/RXR activation, neuroprotective role for THOP1 in Alzheimer's disease, and glutamate receptor signaling pathways were observed to be mostly downregulated in advanced cancer stage. While some of these highlighted markers and signaling pathways are commonly found in the central nervous system (CNS), our results suggest a novel function of these genes in the periphery. Finally, our study underscores the value of implementing appropriate normalization methods in comparative studies to improve the identification of accurate and reliable markers.

Vaginal Squamous Cell Carcinoma Develops in Mice with Conditional Arid1a Loss and Gain of Oncogenic Kras Driven by Progesterone Receptor Cre

Oncogenic KRAS mutations are a common finding in endometrial cancers. Recent sequencing studies indicate that loss-of-function mutations in the ARID1A gene are enriched in gynecologic malignant tumors. However, neither of these genetic insults alone are sufficient to develop gynecologic cancer. To determine the role of the combined effects of deletion of Arid1a and oncogenic Kras, Arid1a^flox/flox mice were crossed with Kras^{Lox-Stop-Lox-G12D/+} mice using progesterone receptor Cre (Pgr^Cre/+). Histologic analysis and immunohistochemistry of survival studies were used to characterize the mutant mouse phenotype. Hormone dependence was evaluated by ovarian hormone depletion and estradiol replacement. Arid1a^flox/flox; Kras^{Lox-Stop-Lox-G12D/+}; Pgr^Cre/+ mice were euthanized early because of invasive vaginal squamous cell carcinoma. Younger mice had precancerous intraepithelial lesions. Immunohistochemistry supported the pathological diagnosis with abnormal expression and localization of cytokeratin 5, tumor protein P63, cyclin-dependent kinase inhibitor 2A, and Ki-67, the marker of proliferation. Ovarian hormone deletion in Arid1a^flox/flox; Kras^{Lox-Stop-Lox-G12D/+}; Pgr^Cre/+ mice resulted in atrophic vaginal epithelium without evidence of vaginal tumors. Estradiol replacement in ovarian hormone-depleted Arid1a^flox/flox; Kras^{Lox-Stop-Lox-G12D/+}; Pgr^Cre/+ mice resulted in lesions that resembled the squamous cell carcinoma in intact mice. Therefore, this mouse can be used to study the transition from benign precursor lesions into invasive vaginal human papillomavirus-independent squamous cell carcinoma, offering insights into progression and pathogenesis of this rare disease.

The effect of surgical approach on the outcomes and prognosis of high-risk histologic endometrioid carcinomas

Background

High-risk histologic endometrioid carcinomas include poorly differentiated endometrial carcinoma (PDEC), uterine clear cell carcinoma (UCCC), uterine carcinosarcoma (UCS), and uterine papillary serous carcinomas (UPCS). The purpose of this study was to investigate and compare the effect of open surgery and minimally invasive surgery on the prognosis of patients with high-risk endometrial cancer tissue types.

Methods

A retrospective analysis was conducted to investigate 57 UCS or UPCS, 53 UCCC, and 110 PDEC patients receiving initial treatment at the Department of Gynecology in Shaanxi Provincial Tumor hospital and the Affiliated Hospital of Medical College of Xi'an Jiaotong University between February 2010 and January 2015. Prognostic factors were determined using univariate/multivariate analysis, and survival rates were assessed using the Kaplan-Meier method. The Cox regression model was adopted to assess the independent prognostic factors.

Results

Two hundred and twenty patients who met the criteria were included in this study. At the end of follow-up period, 94 patients were still alive. Univariate analysis found that the survival time of the patients was related to staging, adjuvant therapy, and surgical approach. Multivariate analysis revealed that surgical approach, staging, pathology, and adjuvant therapy were independent prognostic factors.

Conclusions

Minimally invasive surgery has a shorter survival time compared to open surgery in women with PDEC, UCCC, UCS, and UPCS. Multivariate analysis confirmed that staging, pathological type, surgical approach, and postoperative adjuvant therapy are independent risk factors for prognosis and affect the survival of women with PDEC, UCCC, UCS, and UPCS.

Endometrial cancer-is our knowledge changing?

In developed countries, endometrial cancer (EC) is the most frequent gynecologic malignancy in postmenopausal women. At the same time, EC has become one of the most common cancers in numerous developing countries, probably influenced by global epidemic of obesity. The majority of patients have low-grade endometrioid cancer with a high 5-year survival rate, but with high-risk EC, the survival rates are still rather low. However, despite intensive research in last decades, our knowledge of the mechanisms, risk factors, diagnosis and treatment have not significantly improved. The standard treatment of all types of EC is still a traditional combination of surgery, irradiation and/or chemotherapy, despite the fact that each of these options is not without having some negative side effects. Despite the fact that on the molecular level, EC is relatively well-studied, but the efforts to transform these findings into either diagnosis or therapies of EC remain elusive. In addition, some research into risk factors involved in the development or progression of EC seems to be more a fishing expedition than a well thought-out approach. The purpose of this review is to summarize the most recent developments in the search for biomarkers and prognostic markers and to discuss the progress in EC treatment.

Pten and Dicer1 loss in the mouse uterus causes poorly differentiated endometrial adenocarcinoma

Endometrial cancer remains the most common gynecological malignancy in the United States. While the loss of the tumor suppressor, PTEN (phosphatase and tensin homolog), is well studied in endometrial cancer, recent studies suggest that DICER1, the endoribonuclease responsible for miRNA genesis, also plays a significant role in endometrial adenocarcinoma. Conditional uterine deletion of Dicer1 and Pten in mice resulted in poorly differentiated endometrial adenocarcinomas, which expressed Napsin A and HNF1B (hepatocyte nuclear factor 1 homeobox B), markers of clear-cell adenocarcinoma. Adenocarcinomas were hormone-independent. Treatment with progesterone did not mitigate poorly differentiated adenocarcinoma, nor did it affect adnexal metastasis. Transcriptomic analyses of DICER1 deleted uteri or Ishikawa cells revealed unique transcriptomic profiles and global miRNA downregulation. Computational integration of miRNA with mRNA targets revealed deregulated let-7 and miR-16 target genes, similar to published human DICER1-mutant endometrial cancers from TCGA (The Cancer Genome Atlas). Similar to human endometrial cancers, tumors exhibited dysregulation of ephrin-receptor signaling and transforming growth factor-beta signaling pathways. LIM kinase 2 (LIMK2), an essential molecule in p21 signal transduction, was significantly upregulated and represents a novel mechanism for hormone-independent pathogenesis of endometrial adenocarcinoma. This preclinical mouse model represents the first genetically engineered mouse model of poorly differentiated endometrial adenocarcinoma.

Utilization and survival outcomes of sequential, concurrent and sandwich therapies for advanced stage endometrial cancers by histology

OBJECTIVE

To determine the impact on overall survival (OS) of different modalities of adjuvant therapy for the treatment of stage III endometrial cancer (EC), by histology.

METHODS

Stage 3 endometrioid (EAC), serous (SER), clear cell (CC), and carcinosarcoma (CS) patients who underwent primary surgical staging from 2000 to 2013 were identified in SEER-Medicare. Adjuvant therapy was defined by a 4-arm comparator grouping (none; RT only; CT only; combination RT), as well as by an 8-arm comparator grouping (none; RT only; CT only; concurrent CT-RT; concurrent CT-RT then CT; Serial CT-RT; serial RT-CT; sandwich). Modality of RT and CT were analyzed using Kaplan-Meier estimates, log rank tests, and multivariable cox modeling.

RESULTS

Of 2870 cases identified (1798 EAC, 606 SER, 118 CC, 348 CS), 31.5% received no adjuvant therapy. The remainder received RT or CT alone, concurrent RT-CT, serial or sandwich modalities. OS differed by adjuvant therapy in adjusted and unadjusted models, when combining all histologies, and when stratifying by histology using both the 4-arm, and 8-arm comparator analyses (log rank p < .05, all). By histology, in adjusted analyses, sandwich modality had the greatest improvement in OS for endometrioid, but pairwise comparisons did not identify a superior chemotherapy-based regimen. For serous and clear cell, the greatest improvement in OS was seen with concurrent RT-CT, and for carcinosarcoma, CT alone.

CONCLUSIONS

OS for advanced EC significantly differs by histology and mode of adjuvant therapy. Future studies should evaluate the efficacy of combination-based adjuvant therapy versus chemotherapy alone, by histologic subtype and molecular signature.

Adjuvant treatment for patients with FIGO stage I uterine serous carcinoma confined to the endometrium

Objectives

The role of adjuvant treatment for early-stage uterine serous carcinoma is not defined. The goal of this study was to investigate the impact of adjuvant treatment on survival of patients with tumors confined to the endometrium.

Methods

Patients diagnosed with stage I uterine serous carcinoma with no myometrial invasion between January 2004 and December 2015 who underwent hysterectomy with at least 10 lymph nodes removed were identified from the National Cancer Database. Adjuvant treatment patterns defined as receipt of chemotherapy and/or radiotherapy within 6 months from surgery were investigated and overall survival was evaluated using Kaplan–Meier curves, and compared with the log-rank test for patients with at least one month of follow-up. A Cox analysis was performed to control for confounders.

Results

A total of 1709 patients were identified; 833 (48.7%) did not receive adjuvant treatment, 348 (20.4%) received both chemotherapy and radiotherapy, 353 (20.7%) received chemotherapy only, and 175 (10.2%) received radiotherapy only. Five-year overall survival rates for patients who did not receive adjuvant treatment (n=736) was 81.9%, compared with 91.3% for those who had chemoradiation (n=293), 85.1% for those who received radiotherapy only (n=143), and 91.0% for those who received chemotherapy only (n=298) (p<0.001). After controlling for age, insurance status, type of treatment facility, tumor size, co-morbidities, and history of another tumor, patients who received adjuvant chemotherapy (HR 0.64, 95% CI 0.42, 0.96), or chemoradiation (HR 0.55, 95% CI 0.35, 0.88) had better survival compared with those who did not receive any adjuvant treatment, while there was no benefit from radiotherapy alone (HR 0.85, 95% CI 0.53, 1.37). There was no survival difference between chemoradiation and chemotherapy only (HR 1.15, 95% CI 0.65, 2.01).

Conclusion

Adjuvant chemotherapy (with or without radiotherapy) is associated with a survival benefit for uterine serous carcinoma confined to the endometrium.