Ovarian Serous Adenocarcinoma Research Articles

Amplification of Hippo Signaling Pathway Genes Is Governed and Implicated in the Serous Subtype-Specific Ovarian Carcino-Genesis.

Among women, ovarian cancer ranks as the fifth most common cause of cancer-related deaths. This study examined the impact of Hippo signaling pathway on ovarian carcinogenesis. Therefore, the signatures related to Hippo signaling pathway were derived from the molecular signatures database (MSigDB) and were used for further analysis. The Z score-based pathway activation scoring method was employed to investigate the expression patterns of these signatures in the mRNA expression profiles of ovarian cancer cohorts. Compared to other subtype tumors, the results of this study show that the Hippo signaling pathway signatures are dysregulated prominently in serous subtype-specific ovarian carcinogenesis. A receiver operating characteristic (ROC) curve-based results of the Hippo gene set, yes-associated protein 1 (YAP1), and mammalian sterile 20-like kinases 1 (MST1) genes can predict the serous subtype tumors by higher specificity and sensitivity with significant areas under the curve values also further reconfirmed these signaling dysregulations. Moreover, these gene sets were studied further for mutation analysis in the profile of high-grade serous ovarian adenocarcinoma in the cBioPortal database. The OncoPrint results reveal that these Hippo signaling pathway genes are amplified highly during the grade three and stage third or fourth of serous type ovarian tumors. In addition, the results of the Dependency Map (DepMap) plot also clearly show that these genes are amplified significantly across the ovarian cancer cell lines. Finally, overall survival (OS) curve plot investigations also revealed that these gene expressions show poor survival patterns linked to highly expressed conditions in serous subtypes of ovarian cancer patients with significant p-values (p < 0.05). Thus, the current finding would help to develop the targeted therapies treatment for serous subtype ovarian carcinogenesis.

Unraveling the molecular mechanisms of lymph node metastasis in ovarian cancer: focus on MEOX1

BackgroundLymph node metastasis (LNM) is a major factor contributing to the high mortality rate of ovarian cancer, making the treatment of this disease challenging. However, the molecular mechanism underlying LNM in ovarian cancer is still not well understood, posing a significant obstacle to overcome.ResultsThrough data mining from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases, we have identified MEOX1 as a specific gene associated with LNM in ovarian cancer. The expression of MEOX1 was found to be relatively high in serous ovarian adenocarcinoma, and its higher expression were associated with increased tumor grade and poorer clinical prognosis for ovarian cancer patients. Bioinformatics analysis revealed that MEOX1 exhibited the highest mRNA levels among all cancer types in ovarian cancer tissues and cell lines. Furthermore, gene set enrichment analysis (GSEA) and pathway analysis demonstrated that MEOX1 was involved in various LNM-related biological activities, such as lymphangiogenesis, lymphatic vessel formation during metastasis, epithelial-mesenchymal transition (EMT), G2/M checkpoint, degradation of extracellular matrix, and collagen formation. Additionally, the expression of MEOX1 was positively correlated with the expression of numerous prolymphangiogenic factors in ovarian cancer. To validate our findings, we conducted experiments using clinical tissue specimens and cell lines, which confirmed that MEOX1 was highly expressed in high-grade serous ovarian cancer (HGSOC) tissues and various ovarian cancer cell lines (A2780, SKOV3, HO8910, and OVCAR5) compared to normal ovarian tissues and normal ovarian epithelial cell line IOSE-80, respectively. Notably, we observed a higher protein level of MEOX1 in tumor tissues of LNM-positive HGSOC compared to LNM-negative HGSOC. Moreover, our fundamental experiments demonstrated that suppression of MEOX1 led to inhibitory effects on ovarian cancer cell proliferation and EMT, while overexpression of MEOX1 enhanced the proliferation and EMT capacities of ovarian cancer cells.ConclusionsThe results of our study indicate that MEOX1 plays a role in the lymph node metastasis of ovarian cancer by regulating multiple biological activities, including the proliferation and EMT of ovarian cancer, lymphangiogenesis, and ECM remodeling. Our findings suggest that MEOX1 could serve as a potential biomarker for the diagnosis and treatment of ovarian cancer with LNM.

An algorithm for the pre-operative differentiation of benign ovarian tumours based on magnetic resonance imaging interpretation in a regional core hospital: a retrospective study

ObjectiveFor selecting minimally invasive surgery (i.e. laparoscopic ovarian cystectomy) for treating ovarian tumours (OTs) in premenopausal patients, the pre-operative differentiation of benign ovarian tumours (Be-OTs) based on magnetic resonance imaging (MRI) interpretation is important. This paper describes the authors’ 8-year experience of approximately 1000 OT cases, and provides information about a diagnostic algorithm to help other hospitals. Study designThe medical records of 901 patients aged < 50 years with OTs from 1 January 2015–31 March 31 2023 were reviewed. First, the accuracy of pre-operative differentiation between Be-OTs and borderline/malignant ovarian tumours (Bo/Ma-OTs) was compared in each type of OT. Second, to identify the factors influencing differentiation between Be-OTs and Bo/Ma-OTs in 164 serous/mucinous ovarian tumours (SM-OTs), a multi-variate logistic regression analysis was performed to assess the effect of 13 factors, including MRI findings, OT size and tumour markers. ResultsIn the comparison of diagnostic accuracy of pre-operative MRI for each OT type, accuracy was found to be notably high for ovarian endometrial cyst (OEC) (n = 409), ovarian mature cystic teratoma (OMCT) (n = 308), ovarian endometrioid adenocarcinoma (OEA) (n = 6) and ovarian clear cell adenocarcinoma (OCCA) (n = 14). On the other hand, discrepancies between MRI and pathological findings often occurred in SM-OTs, including ovarian serous cystadenoma (n = 86), ovarian mucinous adenocarcinoma (n = 61), ovarian serous adenocarcinoma (n = 12) and ovarian mucinous adenocarcinoma (n = 5). In the multi-variate logistic regression analysis of the latter 164 patients, in addition to MRI findings, OT size and carbohydrate antigen 125 also had an effect to some extent. The combination of MRI interpretation and OT size may enhance differentiation of Be-OTs and Bo/Ma-OTs. ConclusionsAmong four types of OTs (OEC, OMCT, OEA and OCCA), MRI interpretation was able to differentiate between Be-OTs and Bo/Ma-OTs almost perfectly. Additionally, to mitigate the difficulty in differentiating SM-OTs, OT size may be useful in combination with MRI findings, although further accumulation and analysis of OT cases is needed.

Changes in urine metabolite concentration as a minimally invasive marker of ovarian serous adenocarcinoma

Introduction. Detection of ovarian cancer (OC) at the earliest possible stages is a priority for gynecological oncology, since 5-year survival rates decrease significantly with the progression of the disease. Currently, there is a huge need for more effective diagnostic methods and approaches. In recent years, fluid biopsy has received increasing attention in precision medicine because it is minimally invasive and can be repeated many times, allowing for realtime disease monitoring.Aim. Study of the urine metabolomic profile of patients with ovarian carcinoma.Materials and methods. To perform metabolomic analysis, 50 urine samples from patients with a diagnosis of serous ovarian carcinoma and 20 samples from apparently healthy individuals were selected. For protein precipitation, 300 mkl of urine was mixed with 600 mkl of a solution of acetonitrile LC-MS (Merck, Germany) and methanol LC-MS (Merck, Germany) (3:1 ratio). Chromatographic separation of metabolites was performed on a Vanquish Flex UHPLC System chromatograph (Thermo Scientific, Germany). The chromatograph was coupled to an Orbitrap Exploris 480 mass spectrometer (Thermo Scientific, Germany) equipped with an electrospray ionization source. Chromatographic separation was carried out on a Hypersil GOLD™ C18 column (1.9mkm, 10 x 2.1 mm) using the following eluents: A, 0.1 % formic acid; B, acetonitrile containing 0.1 % formic acid.Results. A total of 417 metabolites of various classes were identified by HPLC-MS. It was shown that in the urine of patients with OC 14 metabolites (kynurenine, phenylalanyl-valine, lysophosphatidylcholine (18:3), lysophosphatidylcholine (18:2), alanyl-leucine, lysophosphatidylcholine (20:4), L-phenylalanine, phosphatidylinositol (34:1), 5-methoxytryptophan, 2-hydroxymyristic acid, 3-oxocholic acid, lysophosphatidylcholine (14:0), indoleacrylic acid, lysophosphatidylserine (20:4)) had a significantly higher concentration compared to apparently healthy individuals. The content of 12 compounds, on the contrary, was reduced (L-beta-aspartyl-L-phenylalanine, myristic acid, decanoylcarnitine, aspartyl-glycine, malonylcarnitine, 3-hydroxybutyrylcarnitine, 3-methylxanthine, 2,6-dimethylheptanoylcarnitine, 3-oxododecanoic acid, N-acetylproline, L-octanoylcarnitine, capryloylglycine). This indicates a significant metabolomic imbalance in patients with OC.Conclusion. The metabolomic profile study of urine by UHPLC-MS showed that in patients with serous ovarian carcinoma there is an imbalance in the content of certain fatty acids and their derivatives, acylcarnitines, phospholipids, amino acids and their derivatives, as well as some derivatives of nitrogenous bases. At the same time, 26 metabolites with abnormal concentrations in urine may have some potential as non-invasive biomarkers of OC in women belonging to high-risk groups.

Unveiling a Rare Complication: Gemcitabine-Induced Cardiomyopathy in Ovarian Serous Adenocarcinoma

Gemcitabine is a nucleoside analogue and pyrimidine antimetabolite authorized for the treatment of ovarian cancer. It is generally considered safe and well-tolerated, with only a few reported cases of cardiac adverse effects. However, we present a case of gemcitabine-induced dilated cardiomyopathy in a 33-year-old female receiving gemcitabine as second-line therapy for ovarian serous adenocarcinoma. The patient had no history of hypertension or significant cardiac issues. She presented with clinical symptoms, laboratory abnormalities, and imaging findings consistent with congestive cardiac failure, along with a Left Ventricular Ejection Fraction (LVEF) of 25-30%. Gemcitabine administration was immediately discontinued, and treatment with Furosemide, ACE inhibitors, and Beta-blocker agents was initiated. Subsequently, the patient’s condition improved, with the resolution of symptoms and normalization of cardiac findings upon discontinuation of gemcitabine. This is the first reported case demonstrating objective evidence of gemcitabine-induced dilated cardiomyopathy in a patient with ovarian serous adenocarcinoma without a significant cardiac history. Although rare, it is crucial to promptly diagnose gemcitabine-induced cardiomyopathy to initiate appropriate management protocols.

Development of prediction model to estimate future risk of ovarian lesions: A multi-center retrospective study

BackgroundTo develop the preoperative prediction of ovarian lesions using regression-based statistics analyses and machine learning methods based on multiple serological biomarkers in China. Methods1137 patients with ovarian lesions in Zhujiang Hospital and 518 patients in others hospital in China were randomly assigned to training, test and external validation cohorts. Five machine learning classifiers, including Random Forest (RF), Extreme Gradient Boosting (XGB), Support Vector Classifier (SVC), K-nearest Neighbor (KN), Multi-Layer Perceptron (MLP) and the Lasso-Logistics prediction model (LLRM) were used to derive diagnostic information from 23 predictors. ResultsThe RF model had a high diagnostic value (AUC = 0.968) in predicting benign and malignant ovarian disease. Age and MLR were also potential diagnostic indicators for predicting ovarian disease except tumor indicators. The RF model well distinguished borderline ovarian tumors (AUC = 0.742). The RFM had a high predictive power to identify ovarian serous adenocarcinoma (AUC = 0.943) and ovarian endometriosis cysts (AUC = 0.914). ConclusionsThe RF models can effectively predict adnexal lesions, promising to be adjuncts to the preoperative prediction of ovarian cancer.

An artificial intelligence prediction model based on extracellular matrix proteins for the prognostic prediction and immunotherapeutic evaluation of ovarian serous adenocarcinoma.

Background: Ovarian Serous Adenocarcinoma is a malignant tumor originating from epithelial cells and one of the most common causes of death from gynecological cancers. The objective of this study was to develop a prediction model based on extracellular matrix proteins, using artificial intelligence techniques. The model aimed to aid healthcare professionals to predict the overall survival of patients with ovarian cancer (OC) and determine the efficacy of immunotherapy. Methods: The Cancer Genome Atlas Ovarian Cancer (TCGA-OV) data collection was used as the study dataset, whereas the TCGA-Pancancer dataset was used for validation. The prognostic importance of 1068 known extracellular matrix proteins for OC were determined by the Random Forest algorithm and the Lasso algorithm establishing the ECM risk score. Based on the gene expression data, the differences in mRNA abundance, tumour mutation burden (TMB) and tumour microenvironment (TME) between the high- and low-risk groups were assessed. Results: Combining multiple artificial intelligence algorithms we were able to identify 15 key extracellular matrix genes, namely, AMBN, CXCL11, PI3, CSPG5, TGFBI, TLL1, HMCN2, ESM1, IL12A, MMP17, CLEC5A, FREM2, ANGPTL4, PRSS1, FGF23, and confirm the validity of this ECM risk score for overall survival prediction. Several other parameters were identified as independent prognostic factors for OC by multivariate COX analysis. The analysis showed that thyroglobulin (TG) targeted immunotherapy was more effective in the high ECM risk score group, while the low ECM risk score group was more sensitive to the RYR2 gene-related immunotherapy. Additionally, the patients with low ECM risk scores had higher immune checkpoint gene expression and immunophenoscore levels and responded better to immunotherapy. Conclusion: The ECM risk score is an accurate tool to assess the patient's sensitivity to immunotherapy and forecast OC prognosis.

Adavosertib Enhances Antitumor Activity of Trastuzumab Deruxtecan in HER2-Expressing Cancers.

Cyclin E (CCNE1) has been proposed as a biomarker of sensitivity to adavosertib, a Wee1 kinase inhibitor, and a mechanism of resistance to HER2-targeted therapy. Copy number and genomic sequencing data from The Cancer Genome Atlas and MD Anderson Cancer Center databases were analyzed to assess ERBB2 and CCNE1 expression. Molecular characteristics of tumors and patient-derived xenografts (PDX) were assessed by next-generation sequencing, whole-exome sequencing, fluorescent in situ hybridization, and IHC. In vitro, CCNE1 was overexpressed or knocked down in HER2+ cell lines to evaluate drug combination efficacy. In vivo, NSG mice bearing PDXs were subjected to combinatorial therapy with various treatment regimens, followed by tumor growth assessment. Pharmacodynamic markers in PDXs were characterized by IHC and reverse-phase protein array. Among several ERBB2-amplified cancers, CCNE1 co-amplification was identified (gastric 37%, endometroid 43%, and ovarian serous adenocarcinoma 41%). We hypothesized that adavosertib may enhance activity of HER2 antibody-drug conjugate trastuzumab deruxtecan (T-DXd). In vitro, sensitivity to T-DXd was decreased by cyclin E overexpression and increased by knockdown, and adavosertib was synergistic with topoisomerase I inhibitor DXd. In vivo, the T-DXd + adavosertib combination significantly increased γH2AX and antitumor activity in HER2 low, cyclin E amplified gastroesophageal cancer PDX models and prolonged event-free survival (EFS) in a HER2-overexpressing gastroesophageal cancer model. T-DXd + adavosertib treatment also increased EFS in other HER2-expressing tumor types, including a T-DXd-treated colon cancer model. We provide rationale for combining T-DXd with adavosertib in HER2-expressing cancers, especially with co-occuring CCNE1 amplifications. See related commentary by Rolfo et al., p. 4317.

Preclinical testing of farletuzumab ecteribulin (FZEC [MORAb-202]) and MORAb-109, folate receptor α and mesothelin targeting antibody-drug conjugates (ADCs), in rare gynecologic cancers.

e17634 Background: Rare gynecologic cancers, such as ovarian carcinosarcoma (OCS), uterine serous carcinoma (USC) and ovarian clear cell adenocarcinoma (OCCA), have limited treatment options and molecular alterations that drive cell proliferation and drug resistance, resulting in poor overall survival. The anti-microtubule agent (AMA) paclitaxel is used in first-line treatment of most gynecologic cancers; however, the AMA eribulin is known to have additional anticancer properties (Goto et al. Anticancer Res 38:2929, 2018; Ho et al. Cancer Res 82:4457, 2022). Eribulin ADCs have been developed for targeted delivery to limit toxicity and maximize response. FZEC is an anti-folate receptor α (FRA)-eribulin ADC (Shimizu et al. Clin Cancer Res 27:3905, 2021) and MORAb-109 targets eribulin to mesothelin (MSLN; Albone et al. Annals Oncol 31:S491, 2020). Here we provide preclinical data to support clinical trials of FZEC and MORAb-109 in rare gynecologic cancers. Methods: Fresh tumor tissue from patients consented to the WEHI Stafford Fox Rare Cancer Program was used to establish a cohort of patient-derived xenograft (PDX) models of high-grade serous ovarian carcinoma (HGSOC), OCS, USC and OCCA. PDX models were screened for FRA and MSLN expression by IHC and quantified by HALO software, and 15 models were selected for in vivo testing. Tumor-bearing mice were treated with eribulin (1 mg/kg TIW 3 wks), FZEC (12.5 mg/kg Q14Dx3) or MORAb-109 (25 mg/kg Q14Dx3) and compared to standard of care treatments. Results: About 80% of HGSOC PDX models were FRA positive with no difference between models from chemonaïve samples vs multiple lines of prior treatment. FRA expression was frequent in USC and OCCA models, with MSLN seen in a smaller subset. Despite most (80%) models being cisplatin refractory, 11/15 responded to eribulin with the 4 non-responders having high MDR1 expression and being from previously treated patients. Overall, responses to FZEC and MORAb-109 appeared to correlate with FRA and MSLN expression; importantly, some models with moderate to high target antigen expression showed deeper and more durable responses to FZEC and MORAb-109 compared to eribulin. Conclusions: Responses to FZEC and MORAb-109 correlated with FRA and MSLN expression, with equivalent or better activity compared to eribulin in target-positive PDX models of HGSOC, USC and OCCA. [Table: see text]

E030 Rheumatologists beware! Digital ischaemia as a presenting feature in metastatic ovarian cancer

Abstract Background/Aims Digital ischaemia is an umbrella term to describe the spectrum of acral vascular phenomena irrespective of aetiology, ranging from temporary (as in Raynaud’s phenomenon) to permanent (necrosis). It can be the presenting feature in multiple cancer types, and can be present with or without other features of connective tissue disease. Methods A 54-year-old woman was referred to Rheumatology with a four-day history of acute pain and ischaemic discolouration of all her fingertips bilaterally. There was no history of Raynaud’s phenomenon and no other clinical features of connective tissue disease. She had never smoked. There was a family history of breast cancer in her maternal aunt. She was admitted under vascular surgery for urgent review. All ten fingertips were ischaemic, with a capillary refill time of greater than five seconds. The history was otherwise significant for abdominal bloating, altered bowel habit and fatigue. Examination revealed normal peripheral pulses with no bruits, normal heart sounds and chest sounds. Her abdomen was soft with a mildly enlarged liver. Results FBC, U&amp;E, and LFTs showed no abnormalities. CRP, ESR, ANA, serum protein electrophoresis and complement levels were all normal. Blood tests for ANCA, rheumatoid factor and anti-CCP were also negative. Lupus anticoagulant, anti-cardiolipin and anti-B2-glycoprotein were all negative. The tumour marker CA125 was markedly elevated at 837kU/L (0.0-35.0kU/L). A CT abdomen &amp; pelvis showed a large right-sided adnexal mass with multiple enhancing peritoneal and omental nodules and moderate ascites. Biopsy of a metastatic deposit in the omentum revealed high grade serous ovarian adenocarcinoma. Partial improvement in digital ischaemia was achieved with iloprost and maintenance apixaban and sildenafil. Four cycles of carboplatin and paclitaxel chemotherapy produced near-complete resolution of digital ischaemia symptoms, corresponding to a fall in her CA125 level and reduction in the size of the ovarian mass and intra-abdominal metastases on CT. Ten cases of digital ischaemia associated with ovarian cancer have been described prior to this. The age of onset ranged from 45 to 71, with a median age of 56. Most patients had digital ischaemia without features of connective tissue disease. Four had no blood test abnormalities other than a raised tumour marker CA125. The time from onset of digital ischaemia to diagnosis of ovarian cancer ranged from less than one week to 2 years, with a median time of four months. Conclusion This case study supports previous findings that patients with digital ischaemia associated with ovarian cancer may have normal markers of inflammatory or rheumatological disease. Marked therapeutic responses can be achieved with systemic anti-cancer therapies. Therefore, underlying cancer should be suspected in patients with new-onset or worsening digital ischaemia over the age of 45. A high index of suspicion is required - rheumatologists beware! Disclosure J.H. Miller: None. P. Merry: None.

OPTIMISING THE TREATMENT OF PATIENTS WITH ADVANCED OVARIAN CANCER: AN ANALYSIS OF PRELIMINARY RESULTS

Summary. Aim: to evaluate surgical complications, side effects of chemotherapy, 1- and 3-year survival in patients with advanced ovarian cancer against the background of the introduction of optimized personalized treatment. Object and methods: for this purpose, a comparative analysis of the results of clinical examination and treatment of 74 patients with primary serous ovarian adenocarcinoma of stages III–IV (FIGO 2015) who were treated at the University Clinic of Odesa National Medical University was conducted. Patients were divided into 2 groups: Group IA — patients with primary ovarian cancer who were treated with primary cytoreductive surgery (PDS) + adjuvant chemotherapy (ACT) — 43 patients; IB group — patients with primary ovarian cancer who were treated with neoadjuvant chemotherapy (NACT) + interval cytoreductive surgery (ICS) + adjuvant chemotherapy — 16 patients. Results: the absence of statistical difference in the median overall survival in groups IA (PDS + ACT) and IB (NACT + ICS + ACT) was shown to be explained by the complete volume of cytoreduction performed. There was a change in 3-year survival from 56.3 to 70.7% (χ2 = 0.951; p = 0.329) and an increase in 5-year survival from 12.5 to 60.9% (φ = 0.0012; p &lt; 0.05). In group IB, the percentage of postoperative complications in patients and the average length of hospital stay after cytoreductive surgery were lower than in group IA, but the difference was statistically insignificant. When comparing the frequency of side effects of paclitaxel/carboplatin chemotherapy treatment in groups IA and IB, the values of χ2 = 36.441; p = 0.0195 were obtained. Thus, it was proved that in the IB group, the toxic effects of chemotherapy of 3–4 degrees of severity were significantly more common. Conclusions: there was no statistical difference when comparing the median overall survival and progression-free survival in the study groups. It has also been shown that primary cytoreductive surgery with macroscopically visible residual masses, especially in suboptimal and suboptimal volume (CC 2-3), leads to a significant decrease in survival rates in patients with ovarian cancer.

Gene co-expression network analysis revealed novel biomarkers for ovarian cancer.

Ovarian cancer is the second most common gynecologic cancer and remains the leading cause of death of all gynecologic oncologic disease. Therefore, understanding the molecular mechanisms underlying the disease, and the identification of effective and predictive biomarkers are invaluable for the development of diagnostic and treatment strategies. In the present study, a differential co-expression network analysis was performed via meta-analysis of three transcriptome datasets of serous ovarian adenocarcinoma to identify novel candidate biomarker signatures, i.e. genes and miRNAs. We identified 439 common differentially expressed genes (DEGs), and reconstructed differential co-expression networks using common DEGs and considering two conditions, i.e. healthy ovarian surface epithelia samples and serous ovarian adenocarcinoma epithelia samples. The modular analyses of the constructed networks indicated a co-expressed gene module consisting of 17 genes. A total of 11 biomarker candidates were determined through receiver operating characteristic (ROC) curves of gene expression of module genes, and miRNAs targeting these genes were identified. As a result, six genes (CDT1, CNIH4, CRLS1, LIMCH1, POC1A, and SNX13), and two miRNAs (mir-147a, and mir-103a-3p) were suggested as novel candidate prognostic biomarkers for ovarian cancer. Further experimental and clinical validation of the proposed biomarkers could help future development of potential diagnostic and therapeutic innovations in ovarian cancer.

Abstract 4262: Immunotherapy of ovarian cancer targeting FSHR by innate and adaptive immunity

Abstract Ovarian cancer (OC) represents the deadliest gynecologic malignancy. Despite important advances in the field of OC therapy, recurrent OC still has very poor prognosis with a median survival of 1 year. Due to the close interaction between the ovarian cancer cells and tumor microenvironment, development of treatment strategies which not only target the tumor cells but also the components of the tumor microenvironment hold significance. Notably, a prime obstacle in the development of therapies is to identify targets with specific expression limited to the tumor surface and not the healthy tissues. The follicle-stimulating hormone receptor (FSHR) is one such target with selective expression in ovarian granulosa cells and thus, a potentially important therapeutic target in OC. Therefore, we developed monoclonal antibodies against FSHR and focused on studies of the most potent of these reagents. Anti-FSHR antibody bound to diverse FSHR expressing ovarian serous and clear cell adenocarcinoma cells suggesting these antibodies could be used to specifically target OC. We then designed a novel DNA encoded bispecific T cell engager targeting FSHR (FSHRxCD3) and evaluated this bispecific in therapeutic models for the treatment of OC. FSHRxCD3 bispecific in the presence of human PBMCs was highly specific in killing FSHR positive ovarian tumor lines. However, T cell approaches alone may not be fully effective in treating OC, referred as Immunologically “Cold” Tumors. Hence, we hypothesized that engaging the other components of immune system, would provide better tumor control. Increasing lines of evidence suggest that OC is receptive to Natural killer (NK) cell attack. We designed antibodies against human Siglec-7, an inhibitory receptor present on human NK cells and showed they could bind to NK cells. We then used these to create a novel class of bispecific NK engager (NKE) that simultaneously targets both Siglec-7 and FSHR (Siglec-7xFSHR). This NKE was potent at killing FSHR positive OC targets in both in vitro and in vivo assays. Multiple Ovarian tumors including BRCA mutated and PARPi resistant ovarian cancer cells could be targeted by this immune therapy. Our data demonstrate the therapeutic potential of these two novel bispecific molecules and initial studies suggest that their combination may be valuable in patients with OC. Citation Format: Devivasha Bordoloi, Pratik Bhojnagarwala, Abhijeet J. Kulkarni, Opeyemi S. Adeniji, Alfredo Perales-Puchalt, Ryan P. O’Connell, Xizhou Zhu, Elizabeth M. Parzych, Rugang Zhang, Mohamed Abdel-Mohsen, David B. Weiner. Immunotherapy of ovarian cancer targeting FSHR by innate and adaptive immunity [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 4262.

Mesenteric Panniculitis Appears as Metastatic Disease on 18F-FDG-PET/CT Scan.

Mesenteric panniculitis is a rare benign inflammatory process involving mesenteric adipose tissue and the pathogenesis is still unknown. It may present 18Fluorine-fluorodeoxyglucose (18F-FDG) uptake and appear like a malign tumor or metastatic disease. We report a case of 47 year-old woman with serous ovarian adenocarcinoma demonstrating intense 18F-FDG uptake and hyperdense nodularity in mesenteric fatty tissue on post-chemotherapy positron emission tomography/computed tomography imaging. The serum tumor marker (CA-125) level was within the normal range. A correlative magnetic resonance imaging highlighted the diagnosis of mesenteric panniculitis that was also confirmed by clinical follow-up.

Spectrum of BRCA1/2 Mutations in Romanian Breast and Ovarian Cancer Patients.

Background: About 10,000 women are diagnosed with breast cancer and about 2000 women are diagnosed with ovarian cancer each year in Romania. There is an insufficient number of genetic studies in the Romanian population to identify patients at high risk of inherited breast and ovarian cancer. Methods: We evaluated 250 women of Romanian ethnicity with BC and 240 women of Romanian ethnicity with ovarian cancer for the presence of damaging germline mutations in breast cancer genes 1 and 2 (BRCA1 and BRCA2, respectively) using Next-Generation Sequencing (NGS) technology. Results: Of the 250 breast cancer patients, 47 carried a disease-predisposing BRCA mutation (30 patients (63.83%) with a BRCA1 mutation and 17 patients (36.17%) with a BRCA2 mutation). Of the 240 ovarian cancer patients, 60 carried a BRCA mutation (43 patients (72%) with a BRCA1 mutation and 17 patients (28%) with a BRCA2 mutation). In the BRCA1 gene, we identified 18 variants (4 in both patient groups (ovarian and breast cancer patients), 1 mutation variant in the BC patient group, and 13 mutation variants in the ovarian cancer patient group). In the BRCA2 gene, we identified 17 variants (1 variant in both ovarian and breast cancer patients, 6 distinct variants in BC patients, and 10 distinct variants in ovarian cancer patients). The prevailing mutation variants identified were c.3607C>T (BRCA1) (18 cases) followed by c.5266dupC (BRCA1) (17 cases) and c.9371A>T (BRCA2) (12 cases). The most prevalent mutation, BRCA1 c.3607C>T, which is less common in the Romanian population, was mainly associated with triple-negative BC and ovarian serous adenocarcinoma. Conclusion: The results of our analysis may help to establish specific variants of BRCA mutations in the Romanian population and identify individuals at high risk of hereditary breast and ovarian cancer syndrome by genetic testing.

CLO22-060: &gt; 3 Courses of Neo-Adjuvant Chemotherapy (NACT) May Affect Outcomes of Advanced Ovarian Serous Adenocarcinoma Patients

CLO22-060: &gt; 3 Courses of Neo-Adjuvant Chemotherapy (NACT) May Affect Outcomes of Advanced Ovarian Serous Adenocarcinoma Patients

Multi-scale Pan-cancer Integrative Analyses Identify the STAT3-VSIR Axis as a Key Immunosuppressive Mechanism in Head and Neck Cancer.

VSIR is a novel immune checkpoint protein whose expression on tumor cells across cancers remains largely uncharacterized. Here we purposed to decode the pan-cancer biologic and clinical significance of VSIR overexpression in the tumor compartment. We performed multi-omics integrative analyses of 9,735 tumor samples to identify cancers with non-leukocytic expression of VSIR (VSIR High), followed by association with overall survival and immune cell infiltration levels. Orthogonal assessments of VSIR protein expression and lymphocytic infiltration were performed using quantitative immunofluorescence (QIF). Integrative modeling identified a subset of cancer types as being enriched for VSIR High tumors. VSIR High tumors were associated with significantly poorer overall survival in immunogenic ovarian serous adenocarcinoma (SA) and oral cavity squamous cell carcinoma (SCC). QIF assessments in an independent validation cohort confirmed overexpression of VSIR as being associated with poorer overall survival within immunogenic oral cavity SCC. VSIR overexpression was associated with lower CD4 helper T-cell infiltration in both ovarian SA and oral cavity SCC, but did not impact CD8 T-cell infiltration. VSIR overexpressing tumors in both cancer types exhibited significantly higher STAT3 signaling activity. Pharmacologic inhibition of STAT3 signaling resulted in dose-dependent reduction of VSIR expression in ovarian SA and oral cavity SCC cells. The STAT3-VSIR axis is a potentially significant immunomodulatory mechanism in oral cavity and ovarian cancers, whose activation is associated with poorer survival and an immune microenvironment marked by decreased CD4 helper T-cell activity. The role of VSIR as a tumor-intrinsic modulator of resistance to immunotherapy warrants further exploration.

Analysis of the malignant ovarian tumors incidence in the Sumy region in 2014-2018.

Background. Ovarian cancer is a very important pathology of the female reproductive system and tends to increase in incidence and mortality rates around the world. Despite the fact that ovarian cancer prevalence is lower than that of breast and cervical cancer, its mortality rate is three times higher. Aim. To analyze the incidence of ovarian cancer in the female population of Ukraine and the Sumy region in 2014–2018. Methods. Data from the National Cancer Register of Ukraine were used for this work. A statistical analysis of the incidence rates of ovarian cancer in the population of Ukraine and Sumy region was carried out. Results. The highest incidence of ovarian cancer in the Sumy region was detected in 2018 (12.5 cases per 100,000 women), and the lowest - in 2017 (10.4 cases per 100,000 women). This pathology occurs most often in women 60-79 years old. 91% of the tumors were epithelial-stromal tumors, of which 75% were serous ovarian adenocarcinomas. Ovarian cancer in most cases was diagnosed at the third stage of the disease (47% of cases), which indicates a low level of early diagnosis of this tumor. Conclusion. In the Sumy region, a high incidence rate of ovarian cancer was revealed, which exceeds the national one and has a significant age dependence. Serous ovarian adenocarcinoma is the most common type of ovarian cancer. This pathology is diagnosed mainly at the 3rd stage.

StarD13 negatively regulates invadopodia formation and invasion in high-grade serous (HGS) ovarian adenocarcinoma cells by inhibiting Cdc42

Metastasis remains the main challenge to overcome for treating ovarian cancers. In this study, we investigate the potential role of the Cdc42 GAP StarD13 in the modulation of cell motility, invasion in ovarian cancer cells. StarD13 depletion does not affect the 2D motility of ovarian cancer cells. More importantly, StarD13 inhibits matrix degradation, invadopodia formation and cell invasion through the inhibition of Cdc42. StarD13 does not localize to mature TKS4-labeled invadopodia that possess matrix degradation ability, while a Cdc42 FRET biosensor, detects Cdc42 activation in these invadopodia. In fact, StarD13 localization and Cdc42 activation appear mutually exclusive in invadopodial structures. Finally, for the first time we uncover a potential role of Cdc42 in the direct recruitment of TKS4 to invadopodia. This study emphasizes the specific role of StarD13 as a narrow spatial regulator of Cdc42, inhibiting invasion, suggesting the suitability of StarD13 for targeted therapy.

A monoclonal antibody against annexin A2 targets stem and progenitor cell fractions in tumors

The involvement of cancer stem cells (CSCs) in driving tumor dormancy and drug resistance is well established. Most therapeutic regimens however are ineffective in targeting these regenerative populations. We report the development and evaluation of a monoclonal antibody, mAb150, which targets the metastasis associated antigen, Annexin A2 (AnxA2) through recognition of a N-terminal epitope. Treatment with mAb150 potentiated re-entry of CSCs into the cell cycle that perturbed tumor dormancy and facilitated targeting of CSCs as was validated by in vitro and in vivo assays. Epigenetic potentiation further improved mAb150 efficacy in achieving total tumor regression by targeting regenerative populations to achieve tumor regression, specifically in high-grade serous ovarian adenocarcinoma.