Lapatinib and potential prognostic value of EGFR mutations in a Gynecologic Oncology Group phase II trial of persistent or recurrent endometrial cancer

Locally advanced and metastatic endometrial cancer: Current and emerging therapies

Until recently, patients diagnosed with locally advanced and metastatic endometrial cancer faced significant challenges in their treatment due to limited options and poor prognostic outcomes. The sequencing of tumors has been a major advancement in its management. It has led to The Cancer Genome Atlas classification currently used in clinical practice and the initiation of several clinical trials for innovative treatments targeting principally signaling pathways, immune checkpoints, DNA integrity, growth factors, hormonal signaling, and metabolism. Numerous clinical trials are investigating a combinatorial approach of these targeted therapies to counter tumoral resistance, cellular compensatory mechanisms, and tumor polyclonality. This review provides a comprehensive overview of historical, current, and promising therapies in advanced and metastatic endometrial cancer. It particularly highlights clinical research on targeted and hormonal therapies, but also immunotherapy, reflecting the evolving landscape of treatment modalities for this disease.

Nanocarrier-based targeting of metabolic pathways for endometrial cancer: Status and future perspectives

Cancer is the second-most lethal global disease, as per health reports, and is responsible for around 70% of deaths in low- and middle-income countries. Endometrial cancer is one of the emerging malignancies and has been predicted as a public health challenge for the future. Insulin resistance, obesity, and diabetes mellitus are the key metabolic factors that promote risks for the development of endometrial cancer. Various signaling pathways and associated genes are involved in the genesis of endometrial cancer, and any mutation or deletion in such related factors leads to the induction of endometrial cancer. The conventional way of drug delivery has been used for ages but is associated with poor management of cancer due to non-targeting of the endometrial cancer cells, low efficacy of the therapy, and toxicity issues as well. In this context, nanocarrier-based therapy for the management of endometrial cancer is an effective alternate choice that overcomes the problems associated with conventional therapy. In this review article, we highlighted the nanocarrier-based targeting of endometrial cancer, with a special focus on targeting various metabolic signaling pathways. Furthermore, the future perspectives of nanocarrier-based targeting of metabolic pathways in endometrial cancer were also underpinned. It is concluded that targeting metabolic signaling pathways in endometrial cancer via nanocarrier scaffolds is the future of pharmaceutical design for the significant management and treatment of endometrial cancer.

Pharmacological Treatment of Advanced, Persistent or Metastatic Endometrial Cancer: State of the Art and Perspectives of Clinical Research for the Special Issue "Diagnosis and Management of Endometrial Cancer"

Patients with metastatic or recurrent endometrial cancer (EC) not suitable for surgery and/or radiotherapy are candidates for pharmacological treatment frequently with unsatisfactory clinical outcomes. The purpose of this paper was to review the results obtained with chemotherapy, hormonal therapy, biological agents and immune checkpoint inhibitors in this clinical setting. The combination of carboplatin (CBDCA) + paclitaxel (PTX) is the standard first-line chemotherapy capable of achieving objective response rates (ORRs) of 43-62%, a median progression-free survival (PFS) of 5.3-15 months and a median overall survival (OS) of 13.2-37.0 months, respectively, whereas hormonal therapy is sometimes used in selected patients with slow-growing steroid receptor-positive EC. The combination of endocrine therapy with m-TOR inhibitors or cyclin-dependent kinase 4/6 inhibitors is currently under evaluation. Disappointing ORRs have been associated with epidermal growth factor receptor (EGFR) inhibitors, HER-2 inhibitors and multi-tyrosine kinase inhibitors used as single agents, and clinical trials evaluating the addition of bevacizumab to CBDCA + PTX have reported conflicting results. Immune checkpoint inhibitors, and especially pembrolizumab and dostarlimab, have achieved an objective response in 27-47% of highly pretreated patients with microsatellite instability-high (MSI-H)/mismatch repair (MMR)-deficient (-d) EC. In a recent study, the combination of lenvatinib + pembrolizumab produced a 24-week response rate of 38% in patients with highly pretreated EC, ranging from 64% in patients with MSI-H/MMR-d to 36% in those with microsatellite stable/MMR-proficient tumors. Four trials are currently investigating the addition of immune checkpoint inhibitors to PTX + CBDCA in primary advanced or recurrent EC, and two trials are comparing pembrolizumab + lenvatinib versus either CBDCA + PTX as a first-line treatment of advanced or recurrent EC or versus single-agent chemotherapy in advanced, recurrent or metastatic EC after one prior platinum-based chemotherapy.

Human epidermal growth factor receptor 2 targeted therapy in endometrial cancer: Clinical and pathological perspectives

Endometrial cancer is the most common gynecological cancer in developed countries, and its incidence has increased. The majority of patients with endometrial cancer have an early disease and favorable prognosis; however, a significant proportion of endometrial cancer, which mainly comprises high-grade or type II endometrial cancer such as serous, clear cell, and carcinosarcoma, shows advanced/recurrent disease and dismal prognosis. Novel therapeutic development is required for patients with aggressive endometrial cancers. Recent genomic and immunohistochemical analyses revealed human epidermal growth factor receptor 2 (HER2) overexpression/gene amplification in 20%-40% of patients with type II endometrial cancer. Historically, HER2 targeted therapy has been developed for various major cancers, including breast and gastric cancer. Notably, recent advances in HER2 targeted therapy for patients with type II endometrial cancer are also expected to change. Simultaneously, an optimized HER2 test for endometrial cancer as companion diagnostics should be established. In this review, we summarize the recent findings on endometrial cancer, current treatment, optimized HER2 testing, key clinical trials on HER2 targeted therapy, and future directions in aggressive endometrial cancer, including serous carcinoma and carcinosarcoma.

CircZNF124 regulates cell proliferation, leucine uptake, migration and invasion by miR-199b-5p/SLC7A5 pathway in endometrial cancer

BACKGROUND

Recent studies have revealed that circular RNA participates in endometrial carcinoma (EC) progression. Here we investigated the role of circRNA zinc finger protein 124 (circZNF124) in EC genesis and underlying mechanism.

METHODS

The expression levels of circZNF124, microRNA-199b-5p (miR-199b-5p) and solute carrier family 7 member 5 (SLC7A5) were detected by quantitative real-time polymerase chain reaction. The expression of SLC7A5 and other indicated marker proteins was determined by western blot analysis. For functional assay, cell proliferation, leucine uptake and metastasis were investigated by total cell number, cell counting kit-8, cell colony formation, leucine uptake or transwell assay. The interaction between miR-199b-5p and circZNF124 or SLC7A5 was predicted by starbase online database, and identified by mechanism assays. The impact of circZNF124 absence on tumor growth in vivo was revealed by xenograft mouse model assay. Immunohistochemistry assay was implemented to detect the positive expression rate of nuclear proliferation marker (Ki67).

RESULTS

CircZNF124 and SLC7A5 expression were significantly increased, while miR-199b-5p was decreased in EC tissues and cells compared with normal endometrial tissues or cells. CircZNF124 expression was closely associated with EC severity and lymph node metastasis. Additionally, circZNF124 depletion repressed cell proliferation, leucine uptake, migration and invasion in both HEC1A and Ishikawa cells. CircZNF124 regulated SLC7A5 expression by binding to miR-199b-5p. MiR-199b-5p inhibitors or SLC7A5 overexpression attenuated circZNF124 silencing-mediated EC malignant progression. Furthermore, SLC7A5 absence inhibited tumor growth in vivo.

CONCLUSION

CircZNF124 depletion inhibited EC cell malignancy by miR-199b-5p/SLC7A5 pathway, which demonstrated that circZNF124 had the potential as a therapeutic target for EC.

Tailored Therapy Based on Molecular Characteristics in Endometrial Cancer

Management of endometrial cancer, an adenocarcinoma of the endometrium which occupies most uterine corpus neoplasms, including uterine sarcomas, has been more relevant due to its increasing incidence. Extensive research on tumorigenesis molecular mechanisms and molecular characterization across cancers has brought paradigm shifts in the treatment of various malignant tumors. Endometrial cancer treatment has been traditionally guided according to the disease extent or histology types, while recent studies on molecular features have led to the introduction of targeted agents into clinical use, along with conventional chemotherapeutic agents in patients with recurrent or metastatic disease. Considering the proven efficacy and relatively tolerable toxicities of targeted therapies across malignant tumors, improvement of treatment outcomes is also expected in endometrial cancer by adopting an individualized therapy depending on the specific molecular features. Efficacy assessment of new biological agents is still ongoing based on previous preclinical data on endometrial cancer molecular features. Here, endometrial cancer molecular characterization will be reviewed, and then, we will introduce preclinical data, directing the adoption of new biological agents.

Histomolecular features of high-grade endometrial cancers

High-grade endometrial cancers (ECs) are an aggressive subset of ECs accounting for 70-80% of EC-related deaths. Currently, staging surgery, together with chemotherapy or radiotherapy, is the primary treatment strategy for these cancers. The widespread use of next-generation sequencing has led to a refined understanding of EC's genomics with important information for diagnosis and therapy for individual patients (precision medicine). However, advances in the genomics assessment of high-grade tumors have been slower due to their lower incidence than low-grade EC. This article will briefly introduce the current state of knowledge of the genomics of G3 endometrioid EC, serous uterine cancer, clear cell uterine carcinoma and uterine carcinosarcoma and discuss its implications for diagnosis and targeted therapy.

Phase 2 study of cetuximab (Erbitux) in patients with progressive or recurrent endometrial cancer

INTRODUCTION

Overexpression of the epidermal growth factor receptor (EGFR) found in common subtypes of endometrial cancer has been associated with advanced stage disease and a poor prognosis. The purpose of this phase 2 study was to evaluate the efficacy and safety of cetuximab in patients with recurrent endometrial cancer.

METHODS

The study was an open-label phase 2 clinical trial conducted at two institutions. Patients with recurrent or progressive endometrial cancer of any histologic type with the exception of uterine sarcoma received cetuximab at an initial dose of 400 mg/m² IV followed by weekly doses of 250 mg/m². One cycle was considered 4 weeks of treatment. The primary efficacy endpoint was clinical benefit response, defined as a complete or partial response or prolonged stable disease (>8 weeks) by RECIST 1.0 criteria.

RESULTS

A total of 30 patients were enrolled with a median age of 64 years (range 42-83). Of the 20 evaluable patients, three (15%) had clinical benefit response (one complete response, two stable disease). The patient with a clinical benefit response received a total of 27 cycles and the two patients with stable disease were taken off the study due to progression after four and six cycles, respectively. Of the 10 inevaluable patients, nine received ≤1 cycle due to clinical deterioration and one had an anaphylactic reaction. One patient had a grade 3 rash which resolved after a delay in treatment. No dose reduction was reported.

CONCLUSIONS

In this cohort, single agent therapy with cetuximab was well tolerated and had a 15% clinical benefit response. Further studies are required to better identify patients who may respond to this treatment.

Small-Molecule Inhibitors (SMIs) as an Effective Therapeutic Strategy for Endometrial Cancer

Endometrial cancer (EC) is the sixth most common cancer in women. A continued number of low-risk EC patients at diagnosis, as well as patients diagnosed with advanced-stage disease, will experience an aggressive disease. Unfortunately, those patients will present recurrence or overt dissemination. Systemic cytotoxic chemotherapy treatment on advanced, recurrent, or metastatic EC patients has shown poor results, with median survival rates of less than one year, and median progression-free survival rates of four months. Therefore, the search for innovative and alternative drugs or the development of combinatorial therapies involving new targeted drugs and standard regimens is imperative. Over the last few decades, some small-molecule inhibitors have been introduced in the clinics for cancer treatment, but only a few have been approved by the Food and Drug Administration (FDA) for EC treatment. In the present review, we present the current state and future prospects of small-molecule inhibitors on EC treatment, both alone and in combination.

CircRNA hsa_circ_0002577 accelerates endometrial cancer progression through activating IGF1R/PI3K/Akt pathway

Background

Endometrial cancer (EC) is a common gynecologic malignancy worldwide. This study investigated the regulatory effects of circular RNA (circRNA) hsa_circ_0002577 on the tumorigenesis of EC.

Methods

Tumor samples and adjacent normal tissues were obtained from 84 EC patients. Recombinant lentiviral vectors expressing hsa_circ_0002577 (Lv-circRNA), short hairpin RNAs against hsa_circ_0002577 (sh-circRNA), miR-625-5p mimics, miR-625-5p inhibitor, lentiviral vectors expressing insulin-like growth factor 1 receptor (IGF1R) and their corresponding controls were transfected into EC cells as designated. A mouse xenograft model was established in BALB/c mice by inoculating Ishikawa cells transfected with sh-circRNA or control sequence.

Results

Hsa_circ_0002577 was upregulated in EC tissue samples and cells as compared to normal controls. EC patients with higher expression of hsa_circ_0002577 showed poorer overall survival and more advanced tumor stage. EC cells transfected with Lv-circRNA showed promoted proliferation, migration, and invasion, whereas the delivery of sh-circRNA exerted an opposite effect. Further analyses showed that hsa_circ_0002577 acted as a miR-625-5p sponge in EC cells. IGF1R was a potential downstream target of miR-625-5p. The expression of IGF1R in EC tissues was significantly higher than that in matched controls. Hsa_circ_0002577 accelerated EC development by inducing IGF1R expression and activating PI3K/Akt signaling pathway. Also, the knockdown of hsa_circ_0002577 delayed tumor growth and metastasis in the inoculated mice.

Conclusion

Our study showed that circRNA hsa_circ_002577 accelerated EC progression by acting as a miR-625-5p sponge, upregulating IGF1R and activating the PI3K/Akt pathway, suggesting the potential therapeutic use of hsa_circ_002577 in EC treatment.

Trial registration

Not Applicable.

Targeted therapies in gynecological cancers: a comprehensive review of clinical evidence

Advanced and recurrent gynecological cancers are associated with poor prognosis and lack of effective treatment. The developments of the molecular mechanisms on cancer progression provide insight into novel targeted therapies, which are emerging as groundbreaking and promising cancer treatment strategies. In gynecologic malignancies, potential therapeutic targeted agents include antiangiogenic agents, poly (ADP-ribose) polymerase (PARP) inhibitors, tumor-intrinsic signaling pathway inhibitors, selective estrogen receptor downregulators, and immune checkpoint inhibitors. In this article, we provide a comprehensive review of the clinical evidence of targeted agents in gynecological cancers and discuss the future implication.

Pathogenesis and Clinical Management of Uterine Serous Carcinoma

Uterine serous carcinoma (USC) is an aggressive variant of endometrial cancer that has not been well characterized. It accounts for less than 10% of all endometrial cancers and 80% of endometrial cancer–related deaths. Currently, staging surgery together with chemotherapy or radiotherapy, especially vaginal cuff brachytherapy, is the main treatment strategy for USC. Whole-exome sequencing combined with preclinical and clinical studies are verifying a series of effective and clinically accessible inhibitors targeting frequently altered genes, such as HER2 and PI3K3CA, in varying USC patient populations. Some progress has also been made in the immunotherapy field. The PD-1/PD-L1 pathway has been found to be activated in many USC patients, and clinical trials of PD-1 inhibitors in USC are underway. This review updates the progress of research regarding the molecular pathogenesis and putative clinical management of USC.

Targeting human epidermal growth factor receptor 2 (HER2) in gynecologic malignancies

PURPOSE OF REVIEW

The purpose of this review is to describe the role of the human epidermal growth factor receptor 2 (HER2) as a biomarker and potential target in gynecologic malignancies and to describe contemporary updates in the use of anti-HER2 treatments for these cancers.

RECENT FINDINGS

Approximately 25-30% of all patients with uterine serous carcinoma overexpress tumoral HER2. The anti-HER2 antibody trastuzumab represents an effective, targeted therapy with significant efficacy in the treatment of HER2-positive breast and gastric cancer. Recently, trastuzumab efficacy has also been demonstrated in a randomized controlled trial of women with advanced or recurrent uterine serous carcinoma. Additionally, trastuzumab may be effective in women with HER2-positive uterine carcinosarcoma. The role of anti-HER2 therapy is unclear in women with other gynecologic malignancies but is being evaluated.

SUMMARY

HER2 amplification/overexpression is an effective therapeutic target in select gynecologic malignancies, and especially in the rare endometrial cancer subtype, uterine serous carcinoma. As anti-HER2-targeted therapies become increasingly available, more treatment options may become available for women with HER2-positive disease.

Efficacy of afatinib in a HER2 amplification-positive endometrioid adenocarcinoma patient- a case report

Afatinib has improved the prognosis of epidermal growth factor receptor-positive advanced non-small cell lung cancer and has been explored in the treatment of human epidermal growth factor receptor 2 (HER2)-amplified breast cancer. However, its clinical efficacy in HER2-amplified endometrial cancer has not been reported. Herein, we present the clinical benefit of afatinib in a case of stage IIIC endometrioid adenocarcinoma refractory to multiple lines of chemotherapy and eventually developed pulmonary, abdominal and pelvic metastasis. Upon referral to our clinic, capture-based targeted sequencing was performed on both blood and tumor samples and revealed HER2 amplification. The patient was administered with afatinib and achieved partial response (PR) after two months of treatment, reflected by a significant reduction in pulmonary lesions and serum levels of tumor markers including carcinoembryonic antigen (CEA), cancer antigen (CA) 19-9, 125, 15-3 and cytokeratin 19 fragment antigen 21-1 (CY211). The patient passed away after 3 months of afatinib treatment due to suspected complications of severe intestinal obstruction. Our report demonstrates the efficacy of afatinib in a heavily pre-treated HER2-amplified endometrial cancer patient with multi-organ metastasis. This case also highlights the need to include comprehensive mutational profiling in the standard management of endometrial cancer patients for treatment guidance.

PP2A: A Promising Biomarker and Therapeutic Target in Endometrial Cancer

Over the last decade, the use of targeted therapies has immensely increased in the treatment of cancer. However, treatment for endometrial carcinomas (ECs) has lagged behind, although potential molecular markers have been identified. This is particularly problematic for the type II ECs, since these aggressive tumors are usually not responsive toward the current standard therapies. Therefore, type II ECs are responsible for most EC-related deaths, indicating the need for new treatment options. Interestingly, molecular analyses of type II ECs have uncovered frequent genetic alterations (up to 40%) in PPP2R1A, encoding the Aα subunit of the tumor suppressive heterotrimeric protein phosphatase type 2A (PP2A). PPP2R1A mutations were also reported in type I ECs and other common gynecologic cancers, albeit at much lower frequencies (0-7%). Nevertheless, PP2A inactivation in the latter cancer types is common via other mechanisms, in particular by increased expression of Cancerous Inhibitor of PP2A (CIP2A) and PP2A Methylesterase-1 (PME-1) proteins. In this review, we discuss the therapeutic potential of direct and indirect PP2A targeting compounds, possibly in combination with other anti-cancer drugs, in EC. Furthermore, we investigate the potential of the PP2A status as a predictive and/or prognostic marker for type I and II ECs.

Endometrial Cancer: Obesity, Genetics, and Targeted Agents

It is imperative to understand the underlying mechanisms of both endometrial carcinogenesis and recurrence in order to develop more effective prevention and treatment. This article reviews available molecular data, the interplay between endometrial cancer carcinogenesis with obesity and genetics, as well as current targeted therapies.

Molecular-targeted therapies and precision medicine for endometrial cancer

The overall survival rate of patients with early-stage endometrial cancer is relatively high; however, there are few treatment options for patients with advanced or recurrent endometrial cancer, and the prognosis of such patients remains poor. Recent progress in molecular-targeted therapies demonstrated that they have the potential to improve the long-term survival of cancer patients with appropriate biomarkers. However, the median progression-free survival of patients who received single-agent molecular-targeted therapy was <5 months, and the development of molecular-targeted therapies for endometrial cancer patients is urgently needed. This review highlights the previous efforts, including antiangiogenesis therapy, PI3K/AKT/mTOR pathway inhibitor treatment and epidermal growth factor receptor inhibitor treatment and reports on ongoing phase 2 clinical trials, including immune checkpoint inhibitor and PARP inhibitor. We also summarized the genetic background of endometrial cancer according to The Cancer Genome Atlas data and considered the theoretical background for future efforts to prolong the survival of patients with refractory endometrial cancer and for other interesting challenges.

Molecular Genetics of Endometrial Carcinoma

Endometrial cancer is the most commonly diagnosed gynecologic malignancy in the United States. Endometrioid endometrial carcinomas constitute approximately 85% of newly diagnosed cases; serous carcinomas represent approximately 3-10% of diagnoses; clear cell carcinoma accounts for <5% of diagnoses; and uterine carcinosarcomas are rare, biphasic tumors. Longstanding molecular observations implicate PTEN inactivation as a major driver of endometrioid carcinomas; TP53 inactivation as a major driver of most serous carcinomas, some high-grade endometrioid carcinomas, and many uterine carcinosarcomas; and inactivation of either gene as drivers of some clear cell carcinomas. In the past decade, targeted gene and exome sequencing have uncovered additional pathogenic aberrations in each histotype. Moreover, an integrated genomic analysis by The Cancer Genome Atlas (TCGA) resulted in the molecular classification of endometrioid and serous carcinomas into four distinct subgroups, POLE (ultramutated), microsatellite instability (hypermutated), copy number low (endometrioid), and copy number high (serous-like). In this review, we provide an overview of the major molecular features of the aforementioned histopathological subtypes and TCGA subgroups and discuss potential prognostic and therapeutic implications for endometrial carcinoma.

HER2 immunohistochemistry in endometrial and ovarian clear cell carcinoma: discordance between antibodies and with in-situ hybridisation

AIMS

Treatment with anti-HER2 therapy could be beneficial for patients with HER2-positive endometrial and ovarian clear cell carcinoma (CCC). We studied HER2 overexpression by immunohistochemistry (IHC) using three different antibodies, including concordance with amplification by in-situ hybridisation (ISH).

METHODS AND RESULTS

IHC and ISH were performed on tissue microarrays of 101 tumours: 58 endometrial pure CCC, 19 endometrial mixed carcinomas with a CCC component and 24 ovarian pure CCC. IHC was performed using SP3, 4B5 and HercepTest antibodies, and was scored by two independent observers. ISH was performed using dual-colour silver ISH. Using IHC, agreement was poor between SP3/4B5 (61.4%), poor between SP3/HercepTest (68.3%) and reasonable between 4B5/HercepTest (75.2%). Interobserver agreement was substantial to almost perfect for all antibodies (SP3: linear weighted κ = 0.89, 4B5: κ = 0.90, HercepTest: κ = 0.76). HER2-positivity by ISH was 17.8% (endometrial pure CCC: 24.1%, endometrial mixed: 0%, ovarian pure CCC: 16.7%). IHC/ISH concordance was poor, with a high false-negative rate of all three IHC antibodies: sensitivity (38.9-50.0%) and positive predictive value (PPV) (37.5-58.3%) were poor; specificity (81.9-94.0%) and negative predictive value (NPV) (87.1-88.3%) were reasonable. When excluding 2+ cases, sensitivity declined (26.7-43.8%) but PPV (80.0-87.5%) and specificity (98.6-98.7%) improved.

CONCLUSIONS

In ovarian and endometrial CCC, there is considerable difference in HER2 overexpression by different IHC antibodies and marked discordance with ISH. As such, no single antibody can be considered conclusive for determining HER2 status in CCC. Based on these results, the lack of predictive value of different HER2 testing methods, as used in other studies, could be explained.

Targeted Therapies in Type II Endometrial Cancers: Too Little, but Not Too Late

Type II endometrial carcinomas (ECs) are responsible for most endometrial cancer-related deaths due to their aggressive nature, late stage detection and high tolerance for standard therapies. However, there are no targeted therapies for type II ECs, and they are still treated the same way as the clinically indolent and easily treatable type I ECs. Therefore, type II ECs are in need of new treatment options. More recently, molecular analysis of endometrial cancer revealed phosphorylation-dependent oncogenic signalling in the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) and mitogen-activated protein kinase (MAPK) pathways to be most frequently altered in type II ECs. Consequently, clinical trials tested pharmacologic kinase inhibitors targeting these pathways, although mostly with rather disappointing results. In this review, we highlight the most common genetic alterations in type II ECs. Additionally, we reason why most clinical trials for ECs using targeted kinase inhibitors had unsatisfying results and what should be changed in future clinical trial setups. Furthermore, we argue that, besides kinases, phosphatases should no longer be ignored in clinical trials, particularly in type II ECs, where the tumour suppressive phosphatase protein phosphatase type 2A (PP2A) is frequently mutated. Lastly, we discuss the therapeutic potential of targeting PP2A for (re)activation, possibly in combination with pharmacologic kinase inhibitors.

Management Strategies for Recurrent Endometrial Cancer

INTRODUCTION

Endometrial cancer is the most common gynecologic malignancy in the developed world, and its incidence is increasing. Mortality from this cancer has not improved in recent decades and is primarily driven by high-grade carcinomas that are more likely to present at an advanced stage and ultimately are more likely to recur. The prognosis for recurrent endometrial cancer is poor, especially for the 50% of these women that present with extrapelvic disease recurrence. As a standard of care, recurrent disease has been treated with platinum-based chemotherapy; however, new therapies are emerging as we identify drivers of proliferation and metastasis at the cellular and molecular levels. Areas Covered: We review currently available data for the management of recurrent endometrial cancer, with a focus on systemic treatment of recurrent disease. We discuss the available evidence for first-line, second-line, and subsequent systemic therapy and discuss emerging therapeutic targets including their biologic plausibility and early clinical data. Expert Commentary: Endometrial cancer, though prevalent, remains underfunded and understudied. Recurrent and metastatic disease remains difficult to treat, and prospective randomized data are limited. Our ability to reduce mortality due to this cancer is dependent on identifying new and effective therapeutic strategies for recurrent disease.

Hierarchical closeness-based properties reveal cancer survivability and biomarker genes in molecular signaling networks

Specific molecular signaling networks underlie different cancer types and quantitative analyses on those cancer networks can provide useful information about cancer treatments. Their structural metrics can reveal survivability of cancer patients and be used to identify biomarker genes for early cancer detection. In this study, we devised a novel structural metric called hierarchical closeness (HC) entropy and found that it was negatively correlated with 5-year survival rates. We also made an interesting observation that a network of higher HC entropy was likely to be more robust against mutations. This finding suggested that cancers of high HC entropy tend to be incurable because their signaling networks are robust to perturbations caused by treatment. We also proposed a novel core identification method based on the reachability factor in the HC measure. The cores were permitted to decompose such that the negative relationship between HC entropy and cancer survival rate was consistently conserved in every core level. Interestingly, we observed that many promising biomarker genes for early cancer detection reside in the innermost core of a signaling network. Taken together, the proposed analyses of the hierarchical structure of cancer signaling networks may be useful in developing future novel cancer treatments.

Endometrial cancer: Molecular markers and management of advanced stage disease

Endometrial cancer is the most prevalent gynecologic cancer in the United States. Over the last 10 years, death rates from endometrial cancer have been rising about 1.4% per year. Traditionally endometrial cancer treatment has been driven by stage and histology. Recent studies have, however, shown that cancers of the same stage and histology have very distinct molecular and genomic profiles. Translational research is progressing rapidly and endometrial cancer-specific precision medicine is evolving. The first tissue agnostic therapy based on the molecular profile of the tumor was approved by the FDA this year. The approval of immune checkpoint inhibitor, pembrolizumab (anti-PD-1), for all solid tumors with defective DNA mismatch repair, could benefit 20-30% of patients with advanced endometrial cancer. Other genomic changes and molecular markers in endometrial cancer, such as hormone receptor status, could lead to more tailored therapy in the future. Pre-clinical and clinical investigations of targeted therapies suggest efficacy for some agents. Single agent targeted therapies, however, have modest activity. Identifying biomarkers that effectively determine response to targeted therapy remains a challenge. The next generation of clinical trials will focus on novel combinations and how to best utilize the advances that have been made in sequencing technology and bioinformatics. Although there is currently an immense body of data and many options for obtaining genomic characteristics of endometrial cancer, how to interpret and utilize this data is still being explored. This review will summarize the important trials that have led to the treatment options we have for advanced and/or recurrent endometrial cancer and discuss the important studies that have led to a better understanding of the distinctive molecular and genomic profiles within endometrial cancer. We will review the current status of biomarker-driven targeted therapy in endometrial cancer and the rationale behind ongoing clinical trials that are utilizing novel targeted agents.

Verteporfin exhibits YAP-independent anti-proliferative and cytotoxic effects in endometrial cancer cells

Endometrial Carcinoma (EMCA) is the most common gynecologic malignancy and the fourth most common malignancy in women in the United States. Yes-associated protein (YAP) is a potent transcription coactivator acting via binding to the TEAD transcription factor, and plays a critical role in organ size regulation. Verteporfin (VP), a benzoporphyrin derivative, was identified as an inhibitor of YAP-TEAD interaction. We investigated the therapeutic efficacy and mechanism of VP in EMCA. The efficacy of VP on cell viability, cytotoxicity and invasion was assayed in EMCA cell lines. An organoid model system was also developed to test the effect of VP on apoptotic markers in an in vitro model system. Treatment with VP resulted in a decrease in cell viability, invasion and an increase in cytotoxicity of EMCA cells. These effects occurred as early as 15 minutes following treatment. Similarly, VP treatment versus vehicle control increased apoptosis in human organoid model systems. Quantitative RT-PCR, cDNA based RTPCR array analysis and western blotting were performed to investigate the mechanism of VP action. The cytotoxic and anti-proliferative effects appeared to be independent of its effect on YAP. Our results suggest that VP is a promising chemotherapeutic agent for the treatment of endometrial cancer.

Mathematical modeling identifies optimum lapatinib dosing schedules for the treatment of glioblastoma patients

Human primary glioblastomas (GBM) often harbor mutations within the epidermal growth factor receptor (EGFR). Treatment of EGFR-mutant GBM cell lines with the EGFR/HER2 tyrosine kinase inhibitor lapatinib can effectively induce cell death in these models. However, EGFR inhibitors have shown little efficacy in the clinic, partly because of inappropriate dosing. Here, we developed a computational approach to model the in vitro cellular dynamics of the EGFR-mutant cell line SF268 in response to different lapatinib concentrations and dosing schedules. We then used this approach to identify an effective treatment strategy within the clinical toxicity limits of lapatinib, and developed a partial differential equation modeling approach to study the in vivo GBM treatment response by taking into account the heterogeneous and diffusive nature of the disease. Despite the inability of lapatinib to induce tumor regressions with a continuous daily schedule, our modeling approach consistently predicts that continuous dosing remains the best clinically feasible strategy for slowing down tumor growth and lowering overall tumor burden, compared to pulsatile schedules currently known to be tolerated, even when considering drug resistance, reduced lapatinib tumor concentrations due to the blood brain barrier, and the phenotypic switch from proliferative to migratory cell phenotypes that occurs in hypoxic microenvironments. Our mathematical modeling and statistical analysis platform provides a rational method for comparing treatment schedules in search for optimal dosing strategies for glioblastoma and other cancer types.

Clinical trials in gynecologic oncology: Past, present, and future

The Gynecologic Oncology Group has historically performed ground-breaking, practice-changing clinical trials in women's cancers. The current standard of care for initial treatment of ovarian, endometrial, cervical, and trophoblastic cancers was determined by clinical trials completed within this cooperative group structure. For example, trial GOG-0111 set the standard for combining platinum and taxane chemotherapy in ovarian cancer, and more recently GOG-0240 provided evidence for adding bevacizumab to chemotherapy for women with advanced cervical cancer. The landscape of clinical trial design has markedly changed in recent decades, with a clear emphasis on streamlining drug development towards specific patient populations and indications for investigational agents. Translational science in gynecologic cancers can set the stage for rapid and efficient introduction of new therapies for our patients. The gynecologic oncology community of researchers and clinicians is well positioned to enter into the new era of drug development, with breakthrough discoveries increasing each year. It is clear that we must incorporate smarter clinical trial design to get the right drugs to the right patients expeditiously, so we can continue to improve outcome for women with gynecologic cancers.

New therapies for advanced, recurrent, and metastatic endometrial cancers

Endometrial cancer is the most common gynecologic malignancy in the United States, accounting for 6% of cancers in women. In 2017, an estimated 61,380 women were diagnosed with endometrial cancer, and approximately 11,000 died from this disease. From 1987 to 2008, there was a 50% increase in the incidence of endometrial cancer, with an approximate 300% increase in the number of associated deaths. Although there are many chemotherapeutic and targeted therapy agents approved for ovarian, fallopian tube and primary peritoneal cancers, since the 1971 approval of megestrol acetate for the palliative treatment of advanced endometrial cancer, only pembrolizumab has been Food and Drug Administration (FDA)-approved for high microsatellite instability (MSI-H) or mismatch repair deficient (dMMR) endometrial cancer; this highlights the need for new therapies to treat advanced, recurrent, metastatic endometrial cancer. In this review, we discuss current and emerging treatment options for endometrial cancer, including chemotherapy, targeted therapy, and immunotherapy. The National Cancer Institute (NCI) and others are now focusing their efforts on the design of scientifically rational targeted therapy and immunotherapy trials for specific molecular phenotypes of endometrial cancer. This is essential for the advancement of cancer care for women, which is threatened by a severe enrollment decline of approximately 80% for gynecologic oncology clinical trials.

HER2 expression patterns in paired primary and metastatic endometrial cancer lesions

Background:

Despite successful implementation of drugs targeting the human epidermal growth factor receptor 2 (HER2) receptor in breast and gastric cancers, the potential of HER2 as a therapeutic target in other cancers has been less studied, including endometrial cancer. We investigated expression levels of HER2 (ERBB2) in a large cohort of endometrial cancer lesions, also including complex atypical hyperplasia and metastatic lesions.

Methods:

67 precursor lesions, 790 primary endometrial cancers and 383 metastatic lesions were investigated for HER2 expression in relation to clinicopathologic features and outcome. Protein levels were assessed by immunohistochemistry (using the HercepTest and staining index (SI) criteria), mRNA levels by microarrays and amplification status by chromogenic in situ hybridisation.

Results:

High HER2 protein levels were significantly associated with features of aggressive disease and increased mRNA ERBB2 levels. HER2 expression defined by the SI proved to be a better predictor of survival compared with the HercepTest. A discordant HER2 expression pattern between paired primary and metastatic lesions was detected, revealing substantial reduction in HER2 expression from primary to metastatic disease.

Conclusions:

Loss of HER2 expression is common in metastatic endometrial cancer lesions and assessment of HER2 levels in the metastatic lesions may be important to define the potential benefit of anti-HER2 treatments in endometrial cancer patients.

Moving forward with actionable therapeutic targets and opportunities in endometrial cancer: NCI clinical trials planning meeting report on identifying key genes and molecular pathways for targeted endometrial cancer trials

The incidence and mortality rates from endometrial cancer are increasing. There have been no new drugs approved for the treatment of endometrial cancer in decades. The National Cancer Institute, Gynecologic Cancer Steering Committee identified the integration of molecular and/or histologic stratification into endometrial cancer management as a top strategic priority. Based on this, they convened a group of experts to review the molecular data in this disease. Here we report on the actionable opportunities and therapeutic directions identified for incorporation into future clinical trials.

Endometrial Carcinoma: Specific Targeted Pathways

Endometrial cancer (EC) is the most common gynecologic malignancy in the western world with more than 280,000 cases per year worldwide. Prognosis for EC at early stages, when primary surgical resection is the most common initial treatment, is excellent. Five-year survival rate is around 70 %.Several molecular alterations have been described in the different types of EC. They occur in genes involved in important signaling pathways. In this chapter, we will review the most relevant altered pathways in EC, including PI3K/AKT/mTOR, RAS-RAF-MEK-ERK, Tyrosine kinase, WNT/β-Catenin, cell cycle, and TGF-β signaling pathways. At the end of the chapter, the most significant clinical trials will be briefly discussed.This information is important to identify specific targets for therapy.

Cardiac toxicities of lapatinib in patients with breast cancer and other HER2-positive cancers: a meta-analysis

PURPOSE

Lapatinib is a tyrosine kinase inhibitor that targets the human epidermal growth factor receptor 2 (HER2) and the epidermal growth factor receptor (EGFR/HER1), and there are concerns about its cardiac toxicity. Recent studies of lapatinib have reported cardiac adverse events; however, the results have been inconsistent among the studies. The aim of our study was to estimate the cardiac toxicity of lapatinib in patients with breast cancer and other HER2-positive cancers.

METHODS

To evaluate the cardiotoxicity of lapatinib, the results of previous studies were quantitatively integrated using meta-analysis. Forty-five articles regarding cardiac adverse events, including left ventricular dysfunction, left ventricular ejection fraction (LVEF) decrease, arrhythmia, and other cardiac adverse events, were assessed. As a subgroup analysis in patients with breast cancer, 26 studies of lapatinib-induced cardiac adverse events were assessed.

RESULTS

The overall incidence of cardiac adverse events was 2.70% (95% confidence interval [CI] 1.60-4.50%). The incidences of left ventricular dysfunction and LVEF decrease were 1.60% (95% CI 1.30-2.00%) and 2.20% (95% CI 1.30-3.60%), respectively. The overall incidence of cardiac adverse events was 3.00% (95% CI 1.50-6.10%) in patients with breast cancer, which was marginally higher than the rate in patients with all type of cancers.

CONCLUSION

The overall incidence of lapatinib-induced cardiac toxicity was relatively low based on an indirect comparison with trastuzumab. However, careful monitoring of cardiac toxicity is still needed when patients are treated with lapatinib because the related risk factors have not been clearly identified.

Molecular Pathology: Predictive, Prognostic, and Diagnostic Markers in Uterine Tumors

This article focuses on the diagnostic, prognostic, and predictive molecular biomarkers in uterine malignancies, in the context of morphologic diagnoses. The histologic classification of endometrial carcinomas is reviewed first, followed by the description and molecular classification of endometrial epithelial malignancies in the context of histologic classification. Taken together, the molecular and histologic classifications help clinicians to approach troublesome areas encountered in clinical practice and evaluate the utility of molecular alterations in the diagnosis and subclassification of endometrial carcinomas. Putative prognostic markers are reviewed. The use of molecular alterations and surrogate immunohistochemistry as prognostic and predictive markers is also discussed.

SYD985, a Novel Duocarmycin-Based HER2-Targeting Antibody-Drug Conjugate, Shows Antitumor Activity in Uterine and Ovarian Carcinosarcoma with HER2/Neu Expression

Purpose: Carcinosarcomas (CS) are highly aggressive gynecologic malignancies containing both carcinomatous and sarcomatous elements with heterogeneous HER2/neu expression. We compared the efficacy of SYD985 (Synthon Biopharmaceuticals BV), a novel HER2-targeting antibody-drug conjugate (ADC), to trastuzumab emtansine (T-DM1, Genentech-Roche) against primary uterine and ovarian CS.Experimental Design: Eight primary CS cell lines were evaluated for HER2/neu surface expression by IHC and gene amplification by FISH assays. The in vitro experiments included cytotoxicity, antibody-dependent cellular cytotoxicity (ADCC), proliferation, viability, and bystander killing. In vivo activity was studied in mouse xenograft and patient-derived xenograft (PDX) models.Results: SYD985 and T-DM1 induced similar levels of ADCC against CS cell lines with low and high HER2/neu expression when challanged in the presence of effector cells. In contrast, SYD985 was 7- to 54-fold more potent than T-DM1 in the absence of effector cells. SYD985, unlike T-DM1, was active against CS demonstrating low or heterogeneous HER2/neu expression. Specifically, the mean IC₅₀ values were 0.060 μg/mL and 3.221 μg/mL (P < 0.0001) against HER2/neu 0/1+ cell lines and 0.013 μg/mL and 0.096 μg/mL (P < 0.0001) against HER2/neu 3+ cell lines for SYD985 versus T-DM1, respectively. Importantly, unlike T-DM1, SYD985 induced efficient bystander killing of HER2/neu 0/1+ tumor cells admixed with HER2/neu 3+ cells. In vivo studies confirmed that SYD985 is more active than T-DM1 in CS and highly effective against HER2/neu expressing xenografts and PDX.Conclusions: SYD985 may represent a novel and highly effective ADC against HER2-expressing CS. Clinical studies with SYD985 in patients harboring chemotherapy-resistant CS with low/moderate and high HER2 expression are warranted. Clin Cancer Res; 23(19); 5836-45. ©2017 AACR.

Recent Advances in Endometrial Cancer

Endometrial cancer is the most common gynecologic malignancy in the United States, with yearly rates continuing to increase. Most women present with early stage disease; however, advanced disease carries a grave prognosis. As a result, novel therapies are currently under investigation for the treatment of endometrial cancer. These advances include a better understanding of the genetic basis surrounding the development of endometrial cancer, novel surgical therapies, and new molecular targets for the treatment of this disease. This review explores the literature regarding these advancements in endometrial cancer.

New Targeted Agents in Endometrial Cancer: Are We Really Making Progress?

Endometrial cancer is the most common gynecological malignancy in Europe and North America. Metastatic and recurrent disease is generally incurable with poor prognosis. Recent advances in molecular profiling of endometrial cancer have elucidated four distinct molecular subtypes with different biology and prognosis which should facilitate the development of treatments tailored to disease-specific subgroups. To date, some molecular-targeted agents have shown interesting clinical activity in the recurrent setting, but no targeted therapies are approved for endometrial cancer. Novel pan-PI3K, AKT, and dual PI3K-mTOR inhibitors are being investigated with early signs of activity, but there are concerns about tolerability and toxicity in this often elderly patient population with comorbidities. The development of anti-angiogenic therapies, PARP inhibitors, and immunotherapies, alone or in combinations, appear to be promising strategies. This paper will describe the current evidence supporting the efficacy of molecular-targeted agents already tested in the treatment of metastatic and recurrent EC, and provide some insights on emerging data related to novel-targeted therapies.

Chemotherapy for Endometrial Cancer in Adjuvant and Advanced Disease Settings

: Level I evidence exists for use of adjuvant chemotherapy in stage IIIC endometrial cancer (positive lymph nodes), although results of randomized trials have varied. Chemotherapy is also often recommended for high-risk subsets of stage I disease, such as serous carcinomas, although prospective trial data to validate this practice are lacking. Carboplatin plus paclitaxel is the current standard regimen, based on extrapolation of data from the metastatic setting. Several clinical trials have compared adjuvant pelvic radiotherapy alone to a combination of radiotherapy and chemotherapy with mixed results. One of the largest of these trials, Postoperative Radiation Therapy in Endometrial Carcinoma 3 (PORTEC-3), has completed accrual and is awaiting data maturation. Metastatic disease is not curable. For tumors of low-grade endometrioid histology with a prolonged time to recurrence, endocrine therapy with a progestin-based regimen is appropriate. Chemotherapy will be used in most other cases, and the standard first-line regimen is carboplatin and paclitaxel. Few chemotherapy agents have been shown to produce meaningful response rates in the second-line setting. Molecularly targeted therapies such as mTOR inhibitors and antiangiogenic agents including bevacizumab have been studied but their role in the armamentarium remains uncertain.

IMPLICATIONS FOR PRACTICE

Following surgical resection and staging for endometrial cancer, adjuvant chemotherapy with carboplatin and paclitaxel can be administered to patients with a high risk for recurrence. This includes patients with stage IIIC disease with positive lymph nodes, and high-risk subsets of stage I disease such as serous carcinomas. In the metastatic setting, endocrine therapy can be considered, particularly for patients with lower-grade disease and a prolonged time to recurrence. Combined therapy with carboplatin and paclitaxel is the standard of care used for front-line chemotherapy. Antiangiogenic agents are clearly active, but how they should be integrated into treatment is not yet determined. Immunotherapy is a promising direction for patients with mismatch repair-deficient or polymerase ε-mutated tumors.

MUC1 stimulates EGFR expression and function in endometrial cancer

The current standard of care for endometrial cancer patients involves hysterectomy with adjuvant radiation and chemotherapy, with no effective treatment for advanced and metastatic disease. MUC1 is a large, heavily glycosylated transmembrane protein that lubricates and protects cell surfaces and increases cellular signaling through the epidermal growth factor receptor (EGFR). We show for the first time that MUC1 stimulates EGFR expression and function in endometrial cancer. siRNA knockdown and CRISPR/Cas knockout of MUC1 reduced EGFR gene expression, mRNA, protein levels and signaling. MUC1 bound strongly to two regions of the EGFR promoter: -627/-511 and -172/-64. MUC1 knockout also reduced EGFR-dependent proliferation in two dimensional culture, as well as growth and survival in three dimensional spheroid cultures. MUC1 knockout cells were more sensitive to the EGFR inhibitor, lapatinib. Finally, MUC1 and EGFR co-expression was associated with increased cellular proliferation in human endometrial tumors. These data demonstrate the importance of MUC1-driven EGFR expression and signaling and suggest dual-targeted therapies may provide improved response for endometrial tumors.

Ridaforolimus improves the anti-tumor activity of dual HER2 blockade in uterine serous carcinoma in vivo models with HER2 gene amplification and PIK3CA mutation

OBJECTIVE

Uterine serous carcinomas (USC) harbor simultaneous HER2 (ERBB2) over-expression and gain of function mutations in PIK3CA. These concurrent alterations may uncouple single agent anti-HER2 therapeutic efficacy making inhibition of the mammalian target of rapamycin (mTOR) a promising option to heighten anti-tumor response.

METHODS

Both in vitro and in vivo experiments were conducted to assess proliferation, cell death and anti-tumor activity of ridaforolimus, lapatinib and combination lapatinib, trastuzumab (L/T) and ridaforolimus. With institutional approval, NOD/SCID mice bearing xenografts of non-immortalized, HER2 gene amplified cell lines (ARK1, ARK2) with and without PIK3CA gene mutations were divided into four arm cohorts. Ridaforolimus was administered alone and in combination with L/T. Tumor volumes were assessed and posttreatment analysis was performed.

RESULTS

We observed dose dependent in vitro abrogation of downstream target proteins including phospho-AKT and phospho-S6. In both in vivo models, single agent ridaforolimus impaired xenograft tumor growth. Combination ridaforolimus and L/T, however, further improved the observed anti-tumor activity only in the ARK1 model with the PIK3CA gene mutation (E542K). The addition of mTOR inhibition to dual HER2 blockade added no additional anti-tumor effects in the ARK2 xenografts. Western blot and immunohistochemical analysis of downstream pathway alterations following in vivo treatment revealed dual HER2 blockade with ridaforolimus was necessary to induce apoptosis, decrease proliferation and abrogate phospho-S6 protein expression in the PIK3CA mutated model.

CONCLUSIONS

These pilot data suggest that PIK3CA gene mutation may be an effective biomarker for selecting those HER2 over-expressing USC tumors most likely to benefit from mTOR inhibition.

Endometrial Carcinoma: Role of Current and Emerging Biomarkers in Resolving Persistent Clinical Dilemmas

OBJECTIVES

Type II and other high-grade endometrial carcinomas may challenge conventional treatment due to recurrence and metastatic spread and therefore are a persistent clinical dilemma. Effective targeted therapy for these is a goal for clinicians and researchers alike.

METHODS

An extensive review of the literature has been performed for obtaining an in-depth understanding of the clinicopathological characteristics, etiologic factors, and molecular profile of these subsets of endometrial carcinoma. Progress made with current and emerging biomarkers for prognosis assessment and therapeutic targeting has been summarized.

RESULTS

There has been a significant increase in research on potential biomarkers of endometrial cancer, and beneficial targeted therapies have been identified.

CONCLUSIONS

Clinical trials are leading the charge for substantial gains toward personalized treatment of aggressive endometrial carcinoma subtypes.

A phase II evaluation of cediranib in the treatment of recurrent or persistent endometrial cancer: An NRG Oncology/Gynecologic Oncology Group study

PURPOSE

Cediranib is a multi-tyrosine kinase inhibitor targeting vascular endothelial growth factor (VEGF), platelet-derived growth factor (PDGF), and fibroblast growth factor (FGF) receptors. This phase II study was conducted to assess activity and tolerability of single-agent cediranib in recurrent/persistent endometrial cancer.

PATIENTS AND METHODS

Eligible patients had recurrent or persistent endometrial cancer after receiving one or two prior cytotoxic regimens, measurable disease, and Gynecologic Oncology Group (GOG) performance status of ≤2 (≤1 if two prior cytotoxic regimens given). Cediranib 30mg orally daily for a 28daycycle was administered until disease progression or prohibitive toxicity. Microvessel density (MVD) was measured in tumor tissue from initial hysterectomy specimens and correlated with clinical outcome. Primary endpoints were tumor response and surviving progression-free for six months without subsequent therapy (6-month event-free survival [EFS]).

RESULTS

Of 53 patients enrolled, 48 were evaluable for cediranib efficacy and toxicity. Median age was 65.5 years, 52% of patients had received prior radiation, and 73% of patients received only one prior chemotherapy regimen. A partial response was observed in 12.5%. Fourteen patients (29%) had six-month EFS. Median progression-free survival (PFS) was 3.65 months and median overall survival (OS) 12.5 months. No grade 4 or 5 toxicities were observed. A trend towards improved PFS was found in patients whose tumors expressed high MVD.

CONCLUSION

Cediranib as a monotherapy treatment for recurrent or persistent endometrial cancer is well tolerated and met protocol set objectives for sufficient activity to warrant further investigation. MVD may be a useful biomarker for activity.

A phase II trial of trebananib (AMG 386; IND#111071), a selective angiopoietin 1/2 neutralizing peptibody, in patients with persistent/recurrent carcinoma of the endometrium: An NRG/Gynecologic Oncology Group trial

OBJECTIVES

Ang1 & 2 (angiopoietin-1; -2) interact with Tie2 receptors on endothelial cells to mediate vascular remodeling in an angiogenesis signaling pathway distinct from the VEGF axis. Trebananib is a peptide Fc fusion protein that binds Ang1 and 2 and prevents interaction with Tie2. The efficacy of trebananib in recurrent/persistent endometrial cancer (EC) was studied.

METHODS

The primary objective was to determine the frequency of patients with objective tumor responses (ORR) and event-free survival for ≥6months (6-month EFS) and determine toxicity of trebananib at a dose and schedule of 15mg/kg, IV QW. Recurrent/persistent EC, measurable disease, and ≤2 prior chemotherapy lines were required.

RESULTS

Thirty-two patients were eligible and treated. The most common histologies were G1/2 endometrioid (31%), G3 endometrioid (28%) and serous (31.3%). 78% of patients had 1 prior regimen. Patients received 1-9+ cycles of trebananib; 24 patients (75%) received ≤2cycles. One patient had a partial response (3.1%); 8 patients had stable disease (25%) and 5 patients (15.6%) had 6 month EFS. Median progression-free survival and overall-survival were 1.97 months (90% CI 1.77-2.1) and 6.6 months (90% CI 4.01-14.75), respectively. Most common adverse events (AEs) were fatigue, anemia, and GI issues. Grade 3 and 4 AEs were: GI 31 and 0%; vascular 22 and 0%; metabolism/nutrition 19 and 3%; and general (including edema) 16 and 0%.

CONCLUSIONS

Trebananib has insufficient single agent activity in recurrent EC to warrant further investigation at this dose/schedule.

Molecular staging of gynecological cancer: What is the future?

The purpose of cancer staging is to classify cancers into prognostic groups and to allow for comparison of treatment results and survival between patients and institutions. Staging for gynecologic cancers is based on extent of disease and metastasis, which was historically determined by physical examination and is now based on surgical and histologic examination of tumor specimens. Although the extent of disease is currently considered the most important predictor of recurrence and survival, current staging does not include molecular features that are associated with tumor aggressiveness, response to therapy, and prognosis. This review focuses on genomic and proteomic features of gynecologic cancers and the future of biomarkers in staging classification.

The Therapeutic Challenge of Targeting HER2 in Endometrial Cancer

Endometrial cancer is the most common gynecologic cancer in the United States, diagnosed in more than 50,000 women annually. While the majority of women present with low-grade tumors that are cured with surgery and adjuvant radiotherapy, a significant subset of women experience recurrence and do not survive their disease. A disproportionate number of the more than 8,000 annual deaths attributed to endometrial cancer are due to high-grade uterine cancers, highlighting the need for new therapies that target molecular alterations specific to this subset of tumors. Numerous correlative scientific investigations have demonstrated that the HER2 (ERBB2) gene is amplified in 17%-33% of carcinosarcoma, uterine serous carcinoma, and a subset of high-grade endometrioid endometrial tumors. In breast cancer, this potent signature has directed women to anti-HER2-targeted therapies such as trastuzumab and lapatinib. In contrast to breast cancer, therapy with trastuzumab alone revealed no responses in women with recurrent HER2 overexpressing endometrial cancer, suggesting that these tumors may possess acquired or innate trastuzumab resistance mechanisms. This review explores the literature surrounding HER2 expression in endometrial cancer, focusing on trastuzumab and other anti-HER2 therapy and resistance mechanisms characterized in breast cancer but germane to endometrial tumors. Understanding resistance pathways will suggest combination therapies that target both HER2 and key oncogenic escape pathways in endometrial cancer.

IMPLICATIONS FOR PRACTICE

This review summarizes the role of HER2 in endometrial cancer, with a focus on uterine serous carcinoma. The limitations to date of anti-HER2 therapy in this disease site are examined, and mechanisms of drug resistance are outlined based on the experience in breast cancer. Potential opportunities to overcome inherent resistance to anti-HER2 therapy in endometrial cancer are detailed, offering opportunities for further clinical study with the goal to improve outcomes in this challenging disease.

Endometrial metastasis of lung adenocarcinoma: a report of two cases

Case series

Patient: Female, 55 • Female, 51

Final Diagnosis: Metastatic lung adenocarcinoma

Symptoms: Neck swelling

Medication: Erlotinib

Clinical Procedure: Lymph node biopsy

Specialty: Oncology

Phase II evaluation of dalantercept, a soluble recombinant activin receptor-like kinase 1 (ALK1) receptor fusion protein, for the treatment of recurrent or persistent endometrial cancer: an NRG Oncology/Gynecologic Oncology Group Study 0229N

OBJECTIVE

This two-stage phase II study assessed activity of single agent dalantercept in patients with recurrent/persistent endometrial carcinoma (EMC).

METHODS

Eligible patients had persistent/recurrent EMC after 1-2 prior cytotoxic regimens, measurable disease (RECIST 1.1), and GOG performance≤2. Dalantercept 1.2mg/kg subcutaneous was administered once every 3weeks until disease progression (PD)/development of prohibitory toxicity. Primary objectives were to estimate the proportion of patients with persistent/recurrent EMC, who survive progression-free without receiving non-protocol therapy (TPFS) for at least 6months and to estimate the proportion having objective tumor response.

RESULTS

All 28 enrolled patients were eligible and evaluable. Median age: 62years. Most common histologies: 32% Grade 1/2 endometrioid and 54% serous tumors. Prior treatment: 1 or 2 regimens in 82% and 18% of patients, respectively. Eighteen patients received prior radiation therapy. Patients received 1-12 cycles of dalantercept, and 46% of patients received ≤2cycles. The most common adverse events (AE) were fatigue, anemia, constipation and peripheral edema. Grade 3/4 AEs occurred in 39% and 4% of patients. One grade 5 gastric hemorrhage in a patient with a history of radiation fibrosis/small bowel obstruction was deemed possibly dalantercept-related. All patients are off study: 86% for PD. No ORs were observed; 57% had stable disease and 11% had TPFS>6 mos. Median progression-free and overall survival: 2.1months (90% CI: 1.4-3.2) and 14.5months (90% CI: 7.0-17.5), respectively.

CONCLUSIONS

Dalantercept has insufficient single agent activity in recurrent EMC to warrant further investigation at this dose level and schedule.

HER2 over-expressing high grade endometrial cancer expresses high levels of p95HER2 variant

BACKGROUND

Subsets of high grade endometrial cancer (EnCa) over-express HER2 (ERBB2), yet clinical trials have failed to demonstrate any anti-tumor activity utilizing trastuzumab, an approved platform for HER2 positive breast cancer (BrCa). A truncated p95HER2 variant lacking the trastuzumab binding site may confer resistance. The objective of this investigation was to characterize the expression of the p95HER2 truncated variant in EnCa.

MATERIALS AND METHODS

With institutional approval, 86 high grade EnCa tumors were identified with tumor specimens from surgeries performed between 2000 and 2011. Clinical data were collected and all specimens underwent tumor genotyping, HER2 immunohistochemistry (IHC, HercepTest®), HER2 fluorescent in situ hybridization (FISH), along with total HER2 (H2T) and p95HER2 assessment with VeraTag® testing. Regression models were used to compare a cohort of 86 breast tumors selected for equivalent HER2 protein expression.

RESULTS

We identified 44 high grade endometrioid and 42 uterine serous carcinomas (USC). IHC identified high HER2 expression (2+ or 3+) in 59% of the tumors. HER2 gene amplification was observed in 16 tumors (12 USC, 4 endometrioid). Both HER2 gene amplification and protein expression correlated with H2T values. High p95HER2 expression above 2.8RF/mm2 was observed in 53% (n=54) with significant correlation with H2T levels. When matched to a cohort of 107 breast tumors based on HercepTest HER2 expression, high grade EnCa presented with higher p95 levels (p<0.001).

CONCLUSIONS

These data demonstrate that compared to BrCa, high grade EnCa expresses higher levels of p95HER2 possibly providing rationale for the trastuzumab resistance observed in EnCa.