Dual CCNE1/PIK3CA targeting is synergistic in CCNE1-amplified/PIK3CA-mutated uterine serous carcinomas in vitro and in vivo.

BACKGROUND: Clinical options for patients harbouring advanced/recurrent uterine serous carcinoma (USC), an aggressive variant of endometrial tumour, are very limited. Next-generation sequencing (NGS) data recently demonstrated that cyclin E1 (CCNE1) gene amplification and pik3ca driver mutations are common in USC and may therefore represent ideal therapeutic targets. METHODS: Cyclin E1 expression was evaluated by immunohistochemistry (IHC) on 95 USCs. The efficacy of the cyclin-dependent kinase 2/9 inhibitor CYC065 was assessed on multiple primary USC cell lines with or without CCNE1 amplification. Cell-cycle analyses and knockdown experiments were performed to assess CYC065 targeting specificity. Finally, the in vitro and in vivo activity of CYC065, Taselisib (a PIK3CA inhibitor) and their combinations was tested on USC xenografts derived from CCNE1-amplified/pik3ca-mutated USCs. RESULTS: We found that 89.5% of the USCs expressed CCNE1. CYC065 blocked cells in the G1 phase of the cell cycle and inhibited cell growth specifically in CCNE1-overexpressing USCs. Cyclin E1 knockdown conferred increased resistance to CYC065, whereas CYC065 treatment of xenografts derived from CCNE1-amplified USCs significantly reduced tumour growth. The combination of CYC065 and Taselisib demonstrated synergistic effect in vitro and was significantly more effective than single-agent treatment in decreasing tumour growth in xenografts of CCNE1-amplified/pik3ca-mutated USCs. CONCLUSIONS: Dual CCNE1/PIK3CA blockade may represent a novel therapeutic option for USC patients harbouring recurrent CCNE1-amplified/pi3kca-mutated tumours.

Incidental injury and repair of obturator nerve during laparoscopic pelvic lymphadenectomy.

OBJECTIVE: To demonstrate a surgical video wherein left obturator nerve was iatrogenically injured during pelvic lymphadenectomy and repaired immediately with laparoscopic epineural end-to-end tension free anastomosis. METHODS: This is a step-by-step demonstration of an incidental injury and laparoscopic repair of left obturator nerve during pelvic lymphadenectomy. The patient was a 59year-old Hispanic female who was found to have endometrial adenocarcinoma. She was referred to our division for laparoscopic staging during which left obturator nerve was iatrogenically injured. After completion of left pelvic lymphadenectomy, proximal and distal cut ends of the obturator nerve were identified. Careful inspection revealed that the nerve was transected cleanly without any fraying of the edges. Tension-free reattachment of the edges seemed possible without further mobilization of the nerve since the resected part was approximately 5mm. The obturator nerve edges were oriented and stay sutures were placed in order to perform tension-free anastomosis. Epineural end-to-end coaptation was completed with 5-0 polypropylene sutures [1,2]. RESULTS: Postoperatively, the patient did not exhibit any clinically apparent loss of adductor function or any other neurologic deficiency and was discharged home on postoperative day one. Over 6months of follow-up, the patient experienced no residual neuropathy or deficit in the left thigh. CONCLUSION: Laparoscopic repair of a transected obturator nerve during gynecologic surgery is feasible. In this case, immediate repair of the damaged nerve by an experienced laparoscopic gynecologic surgeon did not result in any neurologic deficit postoperatively.

Solitomab, an EpCAM/CD3 bispecific antibody construct (BiTE), is highly active against primary uterine serous papillary carcinoma cell lines in vitro.

BACKGROUND: Uterine serous carcinoma is an aggressive form of endometrial cancer that carries an extremely poor prognosis. Solitomab is a novel bispecific single-chain antibody construct that targets epithelial cell adhesion molecule on tumor cells and also contains a CD3 binding region. We evaluated the expression levels of epithelial cell adhesion molecule and the in vitro activity of solitomab against primary uterine serous carcinoma cell lines in vitro and ex-vivo in the ascites of patients with uterine serous carcinoma. OBJECTIVE: The purpose of this study was to determine the frequency of expression of epithelial cell adhesion molecule on uterine serous carcinoma cell lines and the ability of solitomab to modulate immune responses (T-cell proliferation, activation, cytokine production, and tumor killing) to tumor cells when it is combined with lymphocytes and epithelial cell adhesion molecule-positive cell lines or epithelial cell adhesion molecule-positive ascitic fluid in vitro. STUDY DESIGN: Epithelial cell adhesion molecule expression was evaluated by flow cytometry in a total of 14 primary uterine serous carcinoma cell lines. Sensitivity to solitomab-dependent cellular-cytotoxicity was tested against a panel of primary uterine serous carcinoma cell lines that express different levels of epithelial cell adhesion molecule in standard 4-hour chromium release assays. The proliferative activity, activation, cytokine secretion (ie, type I vs type II), and cytotoxicity of solitomab in autologous tumor-associated T cells in the ascitic fluid of patients with uterine serous carcinoma was also evaluated by carboxyfluorescein succinimidyl ester and flow-cytometry assays. Differences in epithelial cell adhesion molecule expression, solitomab-dependent cellular-cytotoxicity levels were analyzed with the use of an unpaired t test. T-cell activation marker increase and cytokine release were analyzed by a paired t test. RESULTS: Surface expression of epithelial cell adhesion molecule was found in 85.7% (12 of 14) of the uterine serous carcinoma cell lines that were tested by flow cytometry. Epithelial cell adhesion molecule-positive cell lines were found resistant to natural killer cells or T-cell-mediated killing after exposure to peripheral blood lymphocytes in 4-hour chromium-release assays (mean killing ± standard of the mean, 2.7% ± 3.1% after incubation of epithelial cell adhesion molecule-positive cell lines with control bispecific antibody construct). In contrast, after incubation with solitomab, epithelial cell adhesion molecule-positive uterine serous carcinoma cells became highly sensitive to T-cell cytotoxicity (mean killing, 25.7% ± 4.5%; P < .0001) by peripheral blood lymphocytes. Ex vivo incubation of autologous tumor-associated lymphocytes with epithelial cell adhesion molecule that expressed malignant cells in ascites with solitomab resulted in a significant increase in T-cell proliferation in both CD4+ and CD8+ T cells, increase in T-cell activation markers (ie, CD25 and HLA-DR), and a reduction in number of viable uterine serous carcinoma cells in ascites (P < .001). CONCLUSION: Solitomab induces robust immunologic responses in vitro that result in increased T-cell activation, proliferation, production of cytokines, and direct killing of tumor cells. These findings suggest that solitomab may represent a novel, potentially effective agent for the treatment of recurrent/metastatic and/or chemo-resistant uterine serous carcinoma-overexpressing epithelial cell adhesion molecule.

Clostridium perfringens enterotoxin C-terminal domain labeled to fluorescent dyes for in vivo visualization of micrometastatic chemotherapy-resistant ovarian cancer.

Identification of micrometastatic disease at the time of surgery remains extremely challenging in ovarian cancer patients. We used fluorescence microscopy, an in vivo imaging system and a fluorescence stereo microscope to evaluate fluorescence distribution in Claudin-3- and -4-overexpressing ovarian tumors, floating tumor clumps isolated from ascites and healthy organs. To do so, mice harboring chemotherapy-naïve and chemotherapy-resistant human ovarian cancer xenografts or patient-derived xenografts (PDXs) were treated with the carboxyl-terminal binding domain of the Clostridium perfringens enterotoxin (c-CPE) conjugated to FITC (FITC-c-CPE) or the near-infrared (NIR) fluorescent tag IRDye CW800 (CW800-c-CPE) either intraperitoneally (IP) or intravenously (IV). We found tumor fluorescence to plateau at 30 min after IP injection of both the FITC-c-CPE and the CW800-c-CPE peptides and to be significantly higher than in healthy organs (p < 0.01). After IV injection of CW800-c-CPE, tumor fluorescence plateaued at 6 hr while the most favorable tumor-to-background fluorescence ratio (TBR) was found at 48 hr in both mouse models. Importantly, fluorescent c-CPE was highly sensitive for the in vivo visualization of peritoneal micrometastatic tumor implants and the identification of ovarian tumor spheroids floating in malignant ascites that were otherwise not detectable by conventional visual observation. The use of the fluorescent c-CPE peptide may represent a novel and effective optical approach at the time of primary debulking surgery for the real-time detection of micrometastatic ovarian disease overexpressing the Claudin-3 and -4 receptors or the identification of residual disease at the time of interval debulking surgery after neoadjuvant chemotherapy treatment.

Solitomab, an epithelial cell adhesion molecule/CD3 bispecific antibody (BiTE), is highly active against primary chemotherapy-resistant ovarian cancer cell lines in vitro and fresh tumor cells ex vivo.

BACKGROUND: Solitomab is a novel, bispecific, single-chain antibody that targets epithelial cell adhesion molecule (EpCAM) on tumor cells and also contains a cluster of differentiation 3 (CD3) (T-cell coreceptor) binding region. The authors evaluated the in vitro activity of solitomab against primary chemotherapy-resistant epithelial ovarian carcinoma cell lines as well as malignant cells in ascites. METHODS: EpCAM expression was evaluated by flow cytometry in 5 primary ovarian cancer cell lines and in 42 fresh ovarian tumor cell cultures in ascites from patients with mainly advanced or recurrent, chemotherapy-resistant disease. The potential activity of solitomab against EpCAM-positive tumor cells was evaluated by flow cytometry, proliferation, and 4-hour chromium-release, cell-mediated cytotoxicity assays. RESULTS: EpCAM expression was detected by flow cytometry in approximately 80% of the fresh ovarian tumors and primary ovarian tumor cell lines tested. EpCAM-positive, chemotherapy-resistant cell lines were identified as resistant to natural killer cell-mediated or T-cell-mediated killing after exposure to peripheral blood lymphocytes in 4-hour chromium-release assays (mean±standard error of the mean, 3.6%±0.7% of cells killed after incubation of EpCAM-positive cell lines with control bispecific antibody). In contrast, after incubation with solitomab, EpCAM-positive, chemotherapy-resistant cells became highly sensitive to T-cell cytotoxicity (mean±standard error of the mean, 28.2%±2.05% of cells killed; P<.0001) after exposure to peripheral blood lymphocytes. Ex vivo incubation of autologous tumor-associated lymphocytes with EpCAM-expressing malignant cells in ascites with solitomab resulted in a significant increase in T-cell activation markers and a reduction in the number of viable ovarian tumor cells in ascites (P<.001). CONCLUSIONS: Solitomab may represent a novel, potentially effective agent for the treatment of chemotherapy-resistant ovarian cancers that overexpress EpCAM.

PIK3CA oncogenic mutations represent a major mechanism of resistance to trastuzumab in HER2/neu overexpressing uterine serous carcinomas.

OBJECTIVES: We evaluated the role of PIK3CA-mutations as mechanism of resistance to trastuzumab in primary HER2/neu-amplified uterine-serous-carcinoma (USC) cell lines. METHODS: Fifteen whole-exome-sequenced USC cell lines were tested for HER2/neu-amplification and PIK3CA-mutations. Four HER2/neu-amplified USC (2-harbouring wild-type-PIK3CA-genes and 2-harbouring oncogenic-PIK3CA-mutations) were evaluated in in vitro dose-titration-proliferation-assays, cell-viability and HER2 and S6-protein-phosphorylation after exposure to trastuzumab. USC harbouring wild-type-PIK3CA were transfected with plasmids encoding oncogenic PIK3CA-mutations (i.e., H1047R/R93Q) and exposed to trastuzumab. Finally, trastuzumab efficacy was tested by using two USC xenograft mouse models. RESULTS: Seven out of fifteen (46%) of the USC cell lines were HER2/neu-amplified by fluorescence in situ hybridisation. Within these tumours four out of seven (57%) were found to harbour oncogenic PIK3CA-mutations vs two out of eight (25%) of the HER2/neu not amplified cell lines (P=0.01). HER2/neu-amplified/PIK3CA-mutated USC were highly resistant to trastuzumab when compared with HER2/neu-amplified/wild-type-PIK3CA cell lines (P=0.02). HER2/neu-amplified/PIK3CA wild-type cell lines transfected with oncogenic PIK3CA-mutations increased their resistance to trastuzumab (P<0.0001). Trastuzumab was effective in reducing tumour growth (P=0.001) and improved survival (P=0.0001) in mouse xenografts harbouring HER2-amplified/PIK3CA wild-type USC but not in HER2-amplified/PIK3CA-mutated tumours. CONCLUSIONS: Oncogenic PIK3CA mutations are common in HER2/neu-amplified USC and may constitute a major mechanism of resistance to trastuzumab treatment.

Dacomitinib (PF-00299804), a second-generation irreversible pan-erbB receptor tyrosine kinase inhibitor, demonstrates remarkable activity against HER2-amplified uterine serous endometrial cancer in vitro.

Uterine serous carcinoma (USC) is an aggressive subtype of endometrial cancer that carries an extremely poor prognosis. Up to 35 % of USC may overexpress the epidermal growth factor receptor-2 (HER2/neu) at strong (i.e., 3+) level by immunohistochemistry (IHC) or harbor HER2/neu gene amplification by fluorescence in situ hybridization (FISH). In this study, we assessed the sensitivity of a panel of USC cell lines with and without HER2/neu gene amplification to dacomitinib (PF-00299804), an irreversible pan-human epidermal growth factor receptor tyrosine kinase inhibitor. Eight primary cell lines (i.e., four harboring HER2/neu gene amplification by FISH and four FISH- cell lines), all demonstrating similar in vitro growth rates, were evaluated in viability/proliferation assays. The effect of dacomitinib on cell growth, cell cycle distribution, and signaling was determined using flow cytometry-based assays. Dacomitinib caused a significantly stronger growth inhibition in HER2/neu FISH+ USC cell lines when compared to FISH- USC (dacomitinib half maximal inhibitory concentration (IC50) mean ± SEM = 0.02803 ± 0.003355 µM in FISH+ versus 1.498 ± 0.2209 µM in FISH- tumors, P < 0.0001). Dacomitinib growth inhibition was associated with a significant and dose-dependent decline in phosphorylated HER2/neu and S6 transcription factor and a dose-dependent and time-dependent cell cycle arrest in G0/G1 in FISH+ USC. Dacomitinib is remarkably effective against chemotherapy-resistant HER2/neu gene-amplified USC. Clinical studies with dacomitinib in HER2/neu FISH+ USC patients resistant to standard salvage chemotherapy are warranted.

Neratinib shows efficacy in the treatment of HER2 amplified carcinosarcoma in vitro and in vivo.

OBJECTIVE: Carcinosarcoma is a deadly gynecologic malignancy with few effective treatment options. The study of new therapies is difficult because of its rarity. The objective of this study was to determine the efficacy of neratinib in the treatment of HER2 amplified carcinosarcoma. METHODS: The efficacy of neratinib in the treatment of HER2 amplified carcinosarcoma was determined in vitro using seven primary carcinosarcoma cell lines with differential expression of HER2/neu. Data regarding IC50, cell cycle distribution, and cell signaling changes were assessed by flow cytometry. The efficacy of neratinib was determined in treating mice harboring HER2 amplified carcinosarcoma xenografts. RESULTS: Two of seven (28.5%) carcinosarcoma cell lines were HER2/neu amplified. HER2/neu amplified cell lines SARARK6 and SARARK9 were significantly more sensitive to neratinib than the five non-HER2/neu amplified carcinosarcoma cell lines (mean±SEM IC50:0.014µM±0.004vs.0.164µM±0.019 p=0.0003). Neratinib treatment caused a significant build up in G0/G1 phase of the cell cycle, arrest auto phosphorylation of HER2/neu and activation of S6. Neratinib inhibited tumor growth (p=0.012) and prolonged survival in mice harboring HER2 amplified carcinosarcoma xenografts (p=0.0039). CONCLUSIONS: Neratinib inhibits HER2 amplified carcinosarcoma proliferation, signaling, cell cycle progression and tumor growth in vitro. Neratinib inhibits HER2/neu amplified xenograft growth and improves overall survival. Clinical trials are warranted.

Taselisib, a selective inhibitor of PIK3CA, is highly effective on PIK3CA-mutated and HER2/neu amplified uterine serous carcinoma in vitro and in vivo.

OBJECTIVE: To evaluate the efficacy of taselisib, a selective inhibitor of PIK3CA, against primary uterine serous carcinomas (USC) harboring PIK3CA mutations and HER2/neu gene amplification. METHODS: Sensitivity to taselisib was evaluated by flow-cytometry viability assays in vitro against nine primary USC cell lines. Cell cycle distribution and downstream signaling were assessed by measuring the DNA content of cells and by phosphorylation of the S6 protein by flow-cytometry. Preclinical efficacy of taselisib was also evaluated in vivo in a mouse model. RESULTS: Four USC cell lines harbored HER2/neu gene amplification by FISH and two of them harbored oncogenic PIK3CA mutations. Taselisib caused a strong differential growth inhibition in both HER2/neu FISH positive and HER2/neu FISH positive/PIK3CA mutated USC cell lines when compared to lines that were FISH negative and PIK3CA wild type (taselisib IC50 mean±SEM=0.042±0.006µM in FISH+ versus 0.38±0.06µM in FISH-tumors, P<0.0001). Taselisib growth-inhibition was associated with a significant and dose-dependent increase in the percentage of cells in the G0/G1 phase of the cell cycle and dose-dependent decline in the phosphorylation of S6. Taselisib was highly active at reducing tumor growth in vivo in USC mouse xenografts harboring PIK3CA mutation and overexpressing HER2/neu (P=0.007). Mice treated with taselisib had significantly longer survival when compared to control mice (P<0.0001). CONCLUSIONS: Taselisib represents a novel therapeutic option in patients harboring PIK3CA mutations and/or HER2/neu gene amplification.

Neratinib shows efficacy in the treatment of HER2/neu amplified uterine serous carcinoma in vitro and in vivo.

OBJECTIVES: Uterine serous carcinoma (USC) represents an aggressive variant of endometrial cancer and accounts for a large proportion of deaths annually. HER2/neu amplification is associated with USC in approximately 30-35% of cases. The objective of this study was to determine the sensitivity of a panel of primary USC cell lines to the small tyrosine kinase inhibitor neratinib, an ErbB1 and HER2 inhibitor, both in vitro and in vivo. METHODS: HER2/neu amplification was determined by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) in 24 USC cell lines. Flow cytometry was used to determine the effects of neratinib on cell viability, cell cycle distribution and signaling in vitro. Mice harboring HER2/neu amplified xenografts were treated with neratinib to assess the efficacy of the drug in vivo. RESULTS: HER2/neu amplification was noted in 8/24 primary cell lines. Data regarding the efficacy of neratinib was determined using 4 HER2 amplified cell lines and 4 non-amplified cell lines with similar growth rates. Data revealed that cell lines with HER2/neu amplification were exquisitely more sensitive to neratinib compared to non-amplified cell lines (mean ± SEM IC50: 0.011µM ± 0.0008 vs. 0.312µM ± 0.0456 p<0.0001). Neratinib caused arrest in the G0/G1 phase of the cell cycle and resulted in decreased autophosphorylation of HER2 and activation of S6. Neratinib treated mice harboring xenografts of HER2/neu amplified USC showed delayed tumor growth and improved overall survival compared to vehicle (p=0.0019). CONCLUSIONS: Neratinib may be a potential treatment option for patients harboring HER2/neu amplified USC. Clinical trials for this subset of endometrial cancer patients are warranted.

Taxanes: their impact on gynecologic malignancy.

The use of taxanes in the treatment of gynecologic malignancies has expanded tremendously over the past 30 years. Both paclitaxel and docetaxel have unique microtubule stabilizing, antiangiogenic and radiation sensitizing properties that endow them with remarkable activity as chemotherapeutic agents. As research into the appropriate dose, timing, treatment interval, and response rates have been studied, they have emerged as one of the most active agents available in the treatment of gynecologic cancer. The body of research on taxanes continues to expand especially with regard to the use of taxanes in alternative formulations and in combination with newer treatments or routes of treatment. This review focuses on the development of taxanes as an effective therapy in the treatment of gynecologic cancers and data currently available in the literature regarding their efficacy. Future directions of taxane-based chemotherapy with regards to ovarian, uterine, and cervical cancers are also addressed. There is little doubt that taxane-based chemotherapy will remain an integral part of the treatment of gynecologic cancer for the foreseeable future.

Dual-Targeting Nanoparticles for In Vivo Delivery of Suicide Genes to Chemotherapy-Resistant Ovarian Cancer Cells.

Ovarian cancer is the most lethal gynecologic cancer. Claudin-3 and -4, the receptors for Clostridium perfringens enterotoxin (CPE), are overexpressed in more than 70% of these tumors. Here, we synthesized and characterized poly(lactic-co-glycolic-acid) (PLGA) nanoparticles (NPs) modified with the carboxy-terminal-binding domain of CPE (c-CPE-NP) for the delivery of suicide gene therapy to chemotherapy-resistant ovarian cancer cells. As a therapeutic payload, we generated a plasmid encoding for the diphtheria toxin subunit-A (DT-A) under the transcriptional control of the p16 promoter, a gene highly differentially expressed in ovarian cancer cells. Flow cytometry and immunofluorescence demonstrated that c-CPE-NPs encapsulating the cytomegalovirus (CMV) GFP plasmid (CMV GFP c-CPE-NP) were significantly more efficient than control NPs modified with a scrambled peptide (CMV GFP scr-NP) in transfecting primary chemotherapy-resistant ovarian tumor cell lines in vitro (P = 0.03). Importantly, c-CPE-NPs encapsulating the p16 DT-A vector (p16 DT-A c-CPE-NP) were significantly more effective than control p16 DT-A scr-NP in inducing ovarian cancer cell death in vitro (% cytotoxicity: mean ± SD = 32.9 ± 0.15 and 7.45 ± 7.93, respectively, P = 0.03). In vivo biodistribution studies demonstrated efficient transfection of tumor cells within 12 hours after intraperitoneal injection of CMV GFP c-CPE-NP in mice harboring chemotherapy-resistant ovarian cancer xenografts. Finally, multiple intraperitoneal injections of p16 DT-A c-CPE-NP resulted in a significant inhibition of tumor growth compared with control NP in chemotherapy-resistant tumor-bearing mice (P = 0.041). p16 DT-A c-CPE-NP may represent a novel dual-targeting therapeutic approach for the selective delivery of gene therapy to chemotherapy-resistant ovarian cancer cells. Mol Cancer Ther; 16(2); 323-33. ©2016 AACR.

Immunotherapy and targeted therapy for cervical cancer: an update.

The prognosis of patients with metastatic cervical cancer is poor with a median survival of 8-13 months. Despite the potency of chemotherapeutic drugs, this treatment is rarely curative and should be considered palliative only. In the last few years, a better understanding of Human papillomavirus tumor-host immune system interactions and the development of new therapeutics targeting immune check points have renewed interest in the use of immunotherapy in cervical cancer patients. Moreover, next generation sequencing has emerged as an attractive option for the identification of actionable driver mutations and other markers. In this review, we provide background information on the molecular biology of cervical cancer and summarize immunotherapy studies, targeted therapies, including those with angiogenesis inhibitors and tyrosine kinase inhibitors recently completed or currently on-going in cervical cancer patients.

The Role of the Immune System in Ovarian Cancer and Implications on Therapy.

Ovarian cancer is the leading cause of death from gynecologic malignancy in the United States. While the treatment options have improved with conventional cytotoxic chemotherapy and advanced surgical techniques, disease recurrence is common and fatal in nearly all cases. Current evidence suggests that the immune system and its ability to recognize and eliminate microscopic disease is paramount in preventing recurrence. The goal of immunotherapy is to balance the activation of the immune system against cancer while preventing the potential for tremendous toxicity elicited by immune modulation. In this paper we will review the role of immune system in disease pathogenesis and different immunotherapies available for the treatment of ovarian cancer as well as current ongoing studies and potential future directions.

Immune checkpoint inhibitors in gynecologic cancers with lessons learned from non-gynecologic cancers.

INTRODUCTION: The immune system plays a critical role in controlling cancer through a dynamic relationship with cancer cells. Immunotherapy can establish a sustained immune response against recurring cancer cells leading to long-term remissions for cancer patients. The use of immune checkpoint inhibitors, which work by targeting molecules that regulate immune responses, might be a promising avenue of immunotherapeutic research in gynecologic cancers. AREAS COVERED: This review focuses on the use of immune checkpoint inhibitors targeting cytotoxic T lymphocyte antigen-4 (CTLA-4) and the programmed death receptors such as PD-1 and PD1-ligand in gynecologic cancers. Combinatorial approaches utilizing immunotherapeutic agents with conventional treatments as well as immune-related response criteria and the adverse effects arising due to checkpoint inhibitor immunotherapy have been also discussed in the review. EXPERT OPINION: After years of very little success, a better understanding of the pivotal role of the tumor microenvironment in suppressing anticancer immunity and the exploration of treatment regimens using immune checkpoint inhibitors alone or in combination have finally led to the development of effective cancer immunotherapies and to improve survival of patients with certain types of advanced cancers. While the clinical experience with immune checkpoint inhibitors in gynecologic cancer patients remains limited, early signal of clinical activity strongly suggest that immunotherapy will play a significant role in the year to come in at least a subset of gynecologic cancer patients.

An update on the current pharmacotherapy for endometrial cancer.

INTRODUCTION: Endometrial cancer (EC) is the most common gynecologic malignancy in the developed world and is increasing in incidence. While the mainstay of treatment for EC is surgery followed by chemotherapy and/or radiation therapy, the available pharmacotherapies are rapidly and constantly evolving. Understanding these new therapies is an important part of the research and clinical care of women with EC. A review of available literature from MEDLINE (1879-2015) was conducted for the historic treatments and current therapies available for endometrial tumors. AREAS COVERED: This article reviews the current conventional therapies and discusses novel therapeutic agents, some of which are available to clinicians while others are currently being investigated in the preclinical setting. EXPERT OPINION: Genomic and immunohistochemical characterization of endometrial cancer may soon be the best approach for the identification of aggressive forms of tumor. Targeted therapies will soon be standard in the management of endometrial cancer.

Molecular diagnosis and molecular profiling to detect treatment-resistant ovarian cancer.

INTRODUCTION: Epithelial ovarian cancer remains the gynecologic tumor with the highest rate of recurrence after initial optimal cytoreductive surgery followed by adjuvant chemotherapy. Unfortunately, with the development of recurrent ovarian cancer often comes the discovery of chemo-resistant disease. The absence of improvement in long term survival, notwithstanding the use of newer agents as is seen in other cancers, emphasizes the need for improved understanding of the processes that lead to chemo-resistant disease. AREAS COVERED: This review will cover the following topics: 1. Molecular and cellular mechanisms in platinum and paclitaxel resistance 2. Other molecular mediators of chemo-resistance 3. Expression of stem cell markers in ovarian cancer and relationship to chemo-resistance 4. MicroRNA and long non-coding RNA expression in chemo-resistant ovarian cancer 5. Determination of chromosomal aberrations as markers of chemo-resistance 6. Molecular profiling in chemo-resistant disease. A standard MEDLINE search was performed using the key words; ovarian cancer, chemo-resistant disease, molecular profiling, cancer stem cells and chemotherapy. Expert Commentary: Over the next few years the challenge remains to precisely determine the mechanisms responsible for the onset and maintenance of chemo-resistance and to effectively target these mechanisms.

Overexpression of HE4 (human epididymis protein 4) enhances proliferation, invasion and metastasis of ovarian cancer.

Overexpression of Human epididymis protein 4 (HE4) related with a role in ovarian cancer tumorigenesis while little is known about the molecular mechanism alteration by HE4 up regulation. Here we reported that overexpressed HE4 promoted ovarian cancer cells proliferation, invasion and metastasis. Furthermore, human whole genome gene expression profile microarrays revealed that 231 differentially expressed genes (DEGs) were altered in response to HE4, in which MAPK signaling, ECM receptor, cell cycle, steroid biosynthesis pathways were involved. The findings suggested that overexpressed HE4 played an important role in ovarian cancer progression and metastasis and that HE4 has the potential to serve as a novel therapeutic target for ovarian cancer.

SYD985, a Novel Duocarmycin-Based HER2-Targeting Antibody-Drug Conjugate, Shows Antitumor Activity in Uterine Serous Carcinoma with HER2/Neu Expression.

Uterine serous carcinoma (USC) is an aggressive form of endometrial cancer. Up to 35% of USC may overexpress the HER2/neu oncogene at strong (i.e., 3+) levels by IHC while an additional 40% to 50% express HER2/neu at moderate (2+) or low (1+) levels. We investigated the efficacy of SYD985, (Synthon Biopharmaceuticals), a novel HER2-targeting antibody-drug conjugate (ADC) composed of the mAb trastuzumab linked to a highly potent DNA-alkylating agent (i.e., duocarmycin) in USC. We also compared the antitumor activity of SYD985 in head-to-head experiments to trastuzumab emtansine (T-DM1), a FDA-approved ADC, against multiple primary USC cell lines expressing different levels of HER2/neu in in vitro and in vivo experiments. Using antibody-dependent cellular cytotoxicity (ADCC), proliferation, viability, and bystander killing assays as well as propidium iodide-based flow cytometry assays and multiple in vivo USC mouse xenograft models, we demonstrate for the first time that SYD985 is a novel ADC with activity against USC with strong (3+) as well as low to moderate (i.e., 1+/2+) HER2/neu expression. SYD985 is 10- to 70-fold more potent than T-DM1 in comparative experiments and, unlike T-DM1, it is active against USC demonstrating moderate/low or heterogeneous HER2/neu expression. Clinical studies with SYD985 in patients harboring chemotherapy-resistant USC with low, moderate, and high HER2 expression are warranted. Mol Cancer Ther; 15(8); 1900-9. ©2016 AACR.