High-grade Ovarian Cancer Research Articles

Determination of platinum-resistance of women with ovarian cancer by FTIR spectroscopy combined with multivariate analyses and machine learning methods

Patients with high-grade ovarian cancer have a poor prognosis, thus effective treatment remains an unmet medical issue of high importance. Moreover, finding the reason for resistance to cisplatin is a crucial task for the improvement of anti-cancer drugs. In this study, we showed for the first time a chemical difference in a serum collected from platinum-resistance and platinum-sensitive women suffering from ovarian cancer using Fourier Transform InfraRed (FTIR) spectroscopy followed by a data analysis by Principal Component Analysis (PCA), Hierarchical Component Analysis (HCA) and 4 different machine learning algorithms. Obtained results showed a shift of PO2-symmetric vibrations, amide III and amide II were observed on the FTIR spectrum of the serum collected from platinum-resistance women in comparison with the spectrum of the serum from platinum-sensitive women. Furthermore, PCA analysis clearly demonstrated the most important role of amide II and amide I in the differentiation of platinum-sensitive and platinum-resistance women. In addition, machine learning algorithms showed the important role of wavenumber at 1631 cm-1(amide I) and wavenumber at 2993 cm-1 (asymmetric stretching CH3 vibrations). The accuracy of the obtained results was above 92%. Summarizing, FTIR can be used in detection platinum-resistance phenomena.

The Diversity of Methylation Patterns in Serous Borderline Ovarian Tumors and Serous Ovarian Carcinomas.

Background: Changes in DNA methylation patterns are a pivotal mechanism of carcinogenesis. In some tumors, aberrant methylation precedes genetic changes, while gene expression may be more frequently modified due to methylation alterations than by mutations. Methods: Herein, 128 serous ovarian tumors were analyzed, including borderline ovarian tumors (BOTS) with (BOT.V600E) and without (BOT) the BRAF V600E mutation, low-grade (lg), and high-grade (hg) ovarian cancers (OvCa). The methylome of the samples was profiled with Infinium MethylationEPIC microarrays. Results: The biggest number of differentially methylated (DM) CpGs and regions (DMRs) was found between lgOvCa and hgOvCa. By contrast, the BOT.V600E tumors had the lowest number of DM CpGs and DMRs compared to all other groups and, in relation to BOT, their genome was strongly downmethylated. Remarkably, the ten most significant DMRs, discriminating BOT from lgOvCa, encompassed the MHC region on chromosome 6. We also identified hundreds of DMRs, being of potential use as predictive biomarkers in BOTS and hgOvCa. DMRs with the best discriminative capabilities overlapped the following genes: BAIAP3, IL34, WNT10A, NEU1, SLC44A4, and HMOX1, TCN2, PES1, RP1-56J10.8, ABR, NCAM1, RP11-629G13.1, AC006372.4, NPTXR in BOTS and hgOvCa, respectively. Conclusions: The global genome-wide hypomethylation positively correlates with the increasing aggressiveness of ovarian tumors. We also assume that the immune system may play a pivotal role in the transition from BOTS to lgOvCa. Given that the BOT.V600E tumors had the lowest number of DM CpGs and DMRs compared to all other groups, when methylome is considered, such tumors might be placed in-between BOT and OvCa.

GOG-3097/ENGOT-ov81/GTG-UK/RAMP 301: a phase 3, randomized trial evaluating avutometinib plus defactinib compared with investigator’s choice of treatment in patients with recurrent low grade serous ovarian cancer

BackgroundThere are no approved treatments specifically for low grade serous ovarian cancer; current standard of care treatment options are limited in efficacy and tolerability. The combination of avutometinib with defactinib...

High-grade serous ovarian cancer development and anti-PD-1 resistance is driven by IRE1α activity in neutrophils

ABSTRACT High-grade serious ovarian cancer (HGSOC) is an aggressive malignancy that remains refractory to current immunotherapies. While advanced stage disease has been extensively studied, the cellular and molecular mechanisms that promote early immune escape in HGSOC remain largely unexplored. Here, we report that primary HGSO tumors program neutrophils to inhibit T cell anti-tumor function by activating the endoplasmic reticulum (ER) stress sensor IRE1α. We found that intratumoral neutrophils exhibited overactivation of ER stress response markers compared with their counterparts at non-tumor sites. Selective deletion of IRE1α in neutrophils delayed primary ovarian tumor growth and extended the survival of mice with HGSOC by enabling early T cell-mediated tumor control. Notably, loss of IRE1α in neutrophils sensitized tumor-bearing mice to PD-1 blockade, inducing HGSOC regression and long-term survival in ~ 50% of the treated hosts. Hence, neutrophil-intrinsic IRE1α facilitates early adaptive immune escape in HGSOC and targeting this ER stress sensor might be used to unleash endogenous and immunotherapy-elicited immunity that controls metastatic disease.

506LBA (PB-506) LBA Posters: Ablation of Src Family Kinases FGR in hosts reduces confers response of high-grade ovarian cancer to immune checkpoint blockade treatment

506LBA (PB-506) LBA Posters: Ablation of Src Family Kinases FGR in hosts reduces confers response of high-grade ovarian cancer to immune checkpoint blockade treatment

Vitamin D Significantly Inhibits Carcinogenesis in the Mogp-TAg Mouse Model of Fallopian Tube Ovarian Cancer.

Epidemiological and observational studies suggest that vitamin D has potential for the chemoprevention of ovarian cancer. The anticancer effect of vitamin D in the fallopian tube epithelium (FTE), which is now thought to harbor the precursor cells for high grade ovarian cancer, is not known. The purpose of this study was to investigate whether vitamin D can inhibit carcinogenesis in the mogp-TAg fallopian tube (FT) ovarian cancer mouse model and examine underlying mechanisms. To test this hypothesis, 3 groups of 40 5-week-old female mogp-TAg mice were divided equally into two cohorts of 20 mice, treated with either vehicle (vitamin D solvent) or the active 1,25(OH)2D3 analogue EB1089, delivered via mini-pump or IP injection or cholecalciferol delivered in the feed. The FTs were characterized histologically and pathologically after 3 and 7 weeks of treatment. The effect of vitamin D on cultured human FTE cells was also examined. After 3 weeks, vitamin D, delivered as either cholecalciferol or EB1089 significantly inhibited FT carcinogenesis. After 7 weeks, cholecalciferol significantly reduced p53 signatures, serous tubal epithelial carcinoma, FT cancer, and plasma CA125 while increasing apoptosis in the FTE. EB1089 had no significant effect on FT carcinogenesis at 7 weeks. Cholecalciferol significantly reduced proliferation and increased apoptosis in vitro in p53-altered FTE cells. In conclusion, vitamin D inhibited FT carcinogenesis by clearing cells with p53 alterations. These data suggest that vitamin D has merit for the chemoprevention of fallopian tube/ovarian cancer. The optimal chemopreventive effect may be dependent on the route of vitamin D administration.

Increased peritoneal TGF-β1 is associated with ascites-induced NK-cell dysfunction and reduced survival in high-grade epithelial ovarian cancer.

Natural killer (NK) cell therapy represents an attractive immunotherapy approach against recurrent epithelial ovarian cancer (EOC), as EOC is sensitive to NK cell-mediated cytotoxicity. However, NK cell antitumor activity is dampened by suppressive factors in EOC patient ascites. Here, we integrated functional assays, soluble factor analysis, high-dimensional flow cytometry cellular component data and clinical parameters of advanced EOC patients to study the mechanisms of ascites-induced inhibition of NK cells. Using a suppression assay, we found that ascites from EOC patients strongly inhibits peripheral blood-derived NK cells and CD34+ progenitor-derived NK cells, albeit the latter were more resistant. Interestingly, we found that higher ascites-induced NK cell inhibition correlated with reduced progression-free and overall survival in EOC patients. Furthermore, we identified transforming growth factor (TGF)-β1 to correlate with ascites-induced NK cell dysfunction and reduced patient survival. In functional assays, we showed that proliferation and anti-tumor reactivity of CD34+ progenitor-derived NK cells are significantly affected by TGF-β1 exposure. Moreover, inhibition of TGF-β1 signaling with galunisertib partly restored NK cell functionality in some donors. For the cellular components, we showed that the secretome is associated with a different composition of CD45+ cells between ascites of EOC and benign reference samples with higher proportions of macrophages in the EOC patient samples. Furthermore, we revealed that higher TGF-β1 levels are associated with the presence of M2-like macrophages, B cell populations and T-regulatory cells in EOC patient ascites. These findings reveal that targeting TGF-β1 signaling could increase NK cell immune responses in high-grade EOC patients.

Abstract C020: Nuclear encoded mitochondrial protein MAGMAS as a potential predictor of taxane sensitivity in advanced prostate cancer patients and differential diagnostic marker of tumor aggressiveness in men of African ancestry

Abstract Prostate cancer (PCa) is the most commonly diagnosed malignancy and the second leading cause of cancer-related death among men in the United States (U.S.). Strikingly, men of African ancestry (AA) are 1.7 times more likely to be diagnosed with PCa and more than twice as likely to die of PCa than men of European origin (EU). These disparities are driven by socioeconomic, lifestyle, environmental, and biological/genetic factors. Prostate-specific antigen screening is limited in identifying men with aggressive PCa and exposes men to increased harm with minimal reduction in mortality from PCa. Specifically, several studies report that men of AA are considered to have low-risk prostate cancer by clinical parameters, and those who enrolled in active surveillance programs progress to a higher Gleason-grade cancer and high-volume status than men of EA. Also, men of AA in low to moderate-risk groups appear to be at a higher risk for biochemical recurrence after curative-intent treatment. Therefore, there is a need to understand molecular mechanisms underlying PCa aggressiveness in men of AA that are translatable to the clinic as reliable biomarkers and for the development of novel therapeutic targets. Evidence supports that the mitochondria have a fundamental influence on all steps of oncogenesis, including malignant transformation, tumor progression, and treatment resistance. Regarding cancer health disparities, genes encoding mitochondrial complexes involved in oxidative phosphorylation are upregulated to a greater extent in tumor specimens from AA patients than those from EA patients, supporting the rationale for investigating the role of mitochondria in cancer health disparities. This study investigates Magmas, a nuclear-encoded mitochondrial protein, as a potential mitochondrial marker for PCa tumor aggressiveness and a therapeutic target for advanced PCa. Several observations support the rationale for this study: 1) Magmas overexpression in multiple aggressive cancer subtypes, including high-grade prostate, ovarian cancer, and malignant gliomas. 2) AA PCa cell line overexpresses Magmas similar to chemo-resistant PCa cells, whereas the EA cell line is shown to exhibit lower expression. 3) In human cells, overexpression of Magmas suppresses oxidative stress by regulating the reactive oxygen species (ROS) levels. 4) In chemo-resistant PCa cell lines, pharmacological inhibition of Magmas re-sensitized PCa cells to taxane treatment; and 5) non-cytotoxic pharmacological inhibition of Magmas in chemo-resistant PCa cells dramatically reduced clonogenicity potential. We will evaluate the hypothesis that AA PCa tissue will overexpress Magmas and that overexpression will predict tumor aggressiveness, and 2) that pharmacological inhibition of Magmas will overcome treatment resistance in advanced PCa models. The proposed exploratory study is highly relevant as it will reveal the biological basis for race-related differential expression of Magmas, providing critical insights into mitochondrial determinants that contribute to PCa mortality disparities. Citation Format: Alfonso Duran, Kristen Whitley, Krystal Santiago, Bhaskar Das, Carlos Casiano, Frankis Almaguel. Nuclear encoded mitochondrial protein MAGMAS as a potential predictor of taxane sensitivity in advanced prostate cancer patients and differential diagnostic marker of tumor aggressiveness in men of African ancestry [abstract]. In: Proceedings of the 17th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2024 Sep 21-24; Los Angeles, CA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2024;33(9 Suppl):Abstract nr C020.

Potential of AKNA as a Predictive Biomarker for Ovarian Cancer and Its Relationship to Tumor Grading.

Ovarian cancer exhibits a significant prevalence and incidence on a global scale. Low-grade or high-grade epithelial-type ovarian cancer can be classified by using the dualistic model. Inflammation has been associated with AKNA protein by cancer researchers. The potential of AKNA as a cancer biomarker is supported by its significance and association with ovarian carcinoma. Uninvestigated is this enormous potential. This study examines the correlation between AKNA expression in low-grade and high-grade ovarian tumors and its utility as a predictive biomarker for ovarian cancer. This study examined a total of thirty-one samples, which were classified into three groups: cyst, low-grade, and high-grade ovarian carcinoma. The departmental archive was accessed for the following information: age, tumor size, nuclear grade, mitosis, ovary volume, implant tumor status, lymph vascular invasion status, lymph node metastasis, and tumor-infiltrating lymphocyte. The expression of AKNA was determined using IHC staining. The information was collected and analyzed via analysis of variance. The AKNA H-score shows the mean difference between all three groups (P < 0.001). Cysts had the highest AKNA expression, followed by low-grade and high-grade ovarian carcinoma. Higher-grade ovarian cancer expressed less AKNA compared to cysts or low-grade forms of the disease. This considerable difference suggests that AKNA might predict ovarian cancer tumor grade.

749P Luveltamab tazevibulin, an antifolate receptor alpha (FRα) antibody-drug conjugate (ADC), in combination with bevacizumab (bev) in patients with recurrent high-grade epithelial ovarian cancer (EOC): STRO-002-GM2 phase I study

749P Luveltamab tazevibulin, an antifolate receptor alpha (FRα) antibody-drug conjugate (ADC), in combination with bevacizumab (bev) in patients with recurrent high-grade epithelial ovarian cancer (EOC): STRO-002-GM2 phase I study

757P Sustained long-term responders to niraparib maintenance in recurrent platinum-sensitive high-grade ovarian cancer (PSROC): A subanalysis of the GEICO-88R study

757P Sustained long-term responders to niraparib maintenance in recurrent platinum-sensitive high-grade ovarian cancer (PSROC): A subanalysis of the GEICO-88R study

Constraint-based modelling predicts metabolic signatures of low and high-grade serous ovarian cancer

Ovarian cancer is an aggressive, heterogeneous disease, burdened with late diagnosis and resistance to chemotherapy. Clinical features of ovarian cancer could be explained by investigating its metabolism, and how the regulation of specific pathways links to individual phenotypes. Ovarian cancer is of particular interest for metabolic research due to its heterogeneous nature, with five distinct subtypes having been identified, each of which may display a unique metabolic signature. To elucidate metabolic differences, constraint-based modelling (CBM) represents a powerful technology, inviting the integration of ‘omics’ data, such as transcriptomics. However, many CBM methods have not prioritised accurate growth rate predictions, and there are very few ovarian cancer genome-scale studies. Here, a novel method for CBM has been developed, employing the genome-scale model Human1 and flux balance analysis, enabling the integration of in vitro growth rates, transcriptomics data and media conditions to predict the metabolic behaviour of cells. Using low- and high-grade ovarian cancer, subtype-specific metabolic differences have been predicted, which have been supported by publicly available CRISPR-Cas9 data from the Cancer Cell Line Encyclopaedia and an extensive literature review. Metabolic drivers of aggressive, invasive phenotypes, as well as pathways responsible for increased chemoresistance in low-grade cell lines have been suggested. Experimental gene dependency data has been used to validate areas of the pentose phosphate pathway as essential for low-grade cellular growth, highlighting potential vulnerabilities for this ovarian cancer subtype.

Does an Autoimmune Disorder Following Ovarian Cancer Diagnosis Affect Prognosis?

We investigated whether developing an autoimmune disorder (AID) following a high-grade epithelial ovarian cancer diagnosis improves overall survival. This retrospective study included data from women treated for high-grade serous, endometrioid, or transitional cell ovarian, fallopian tube, or peritoneal cancer FIGO stage III or IV at a Swiss cantonal gynecological cancer center (2008-2023). We used Kaplan-Meier estimates and the Cox proportional hazards model using time-varying covariates for the survival function estimation. In all, 9 of 128 patients developed an AID following a cancer diagnosis. The median time from cancer diagnosis to AID was 2 years (IQR 2-5). These women survived for a median of 3031 days (IQR 1765-3963) versus 972 days (IQR 568-1819) for those who did not develop an AID (p = 0.001). The median overall survival of nine women with a pre-existing AID was 1093 days (IQR 716-1705), similar to those who never had an AID. The multivariate analyses showed older age (p = 0.003, HR 1.04, 95% CI 1.013-1.064) was associated with a poorer prognosis, and developing an AID after a cancer diagnosis was associated with longer survival (p = 0.033, HR 0.113, 95% CI 0.015-0.837). Clinical manifestations of autoimmune disorders following ovarian cancer diagnoses were associated with better overall survival (8 versus 2.7 years), indicating an overactive immune response may improve cancer control.

Synergistic antitumor effect of liposomal-based formulations of olaparib and topotecan in primary epithelial ovarian cancer cells

BackgroundOlaparib is a PARP inhibitor inducing synthetic lethality in tumors with deficient homologous recombination (HRD) caused by BRCA1/2 mutations. The FDA has approved monotherapy for first-line platinum-sensitive, recurrent high-grade epithelial ovarian cancer. Combination therapy alongside DNA-damaging therapeutics is a promising solution to overcome the limited efficacy in patients with HRD. The present study was designed to develop topotecan- and olaparib-loaded liposomes (TLL and OLL) and assess the effectiveness of their combination in patient-derived ovarian cancer samples.MethodsWe used HEOC, four clear-cell tumors (EOC 1–4), malignant ascites, and an OCI-E1p endometrioid primary ovarian cancer cell line and performed NGS analysis of BRCA1/2 mutation status. Antiproliferative activity was determined with the MTT assay. The Chou-Talalay algorithm was used to investigate the in vitro pharmacodynamic interactions of TLLs and OLLs.ResultsThe OLL showed significantly higher efficacy in all ovarian cancer types with wild-type BRCA1/2 than a conventional formulation, suggesting potential for increased in vivo efficacy. The TLL revealed substantially higher toxicity to EOC 1, EOC 3, ascites and lower toxicity to HEOC than the standard formulation, suggesting better therapeutic efficacy and safety profile. The combination of studied compounds showed a higher reduction in cell viability than drugs used individually, demonstrating a synergistic antitumor effect at most of the selected concentrations.ConclusionsThe concentration-dependent response of different ovarian cancer cell types to combination therapy confirms the need for in vitro optimization to maximize drug cytotoxicity. The OLL and TLL combination is a promising formulation for further animal studies, especially for eliminating epithelial ovarian cancer with wild-type BRCA1/2.

Pembrolizumab plus chemotherapy in frontline treatment of advanced ovarian cancer: Clinical and translational results from a phase 2 trial.

The efficacy and feasibility of pembrolizumab combined with chemotherapy in frontline management of advanced high-grade epithelial ovarian cancer (EOC) is unknown. Additionally, modification of the tumor microenvironment following neoadjuvant therapy is not well understood. In this single-arm phase 2 trial (this study was registered at ClinicalTrials.gov: NCT02520154), eligible patients received up to 4 cycles of neoadjuvant chemotherapy followed by interval cytoreduction, 3 cycles of adjuvant intravenous carboplatin/weekly paclitaxel/pembrolizumab, and finally maintenance pembrolizumab until progression or toxicity (maximum 20 cycles). The primary endpoint was progression-free survival (PFS). Secondary endpoints included feasibility, toxicity, and overall survival (OS). PD-L1 staining, multiplex immunofluorescence staining, RNA sequencing, reverse-phase protein array analyses were performed on pre- and post-chemotherapy samples. Thirty-one eligible patients were enrolled. Median PFS and OS was 14.88 (95% CI 12.39-23.00) and 57.43months (95% CI 30.88-not reached), respectively. Among those with PD-L1 combined positive score (CPS) ≥10, the median PFS and OS were not reached compared to those with CPS <10 (10.50 and 30.90months, respectively). Feasibility was met, with all patients completing their planned adjuvant cycles. Treatment discontinuation due to immune-related toxicity occurred in 6 patients (20%). Chemotherapy resulted in an infiltration of anti-tumor immune cells in the tumor microenvironment. Samples of patients with the best PFS demonstrated increased expression of NF-κB, TGF-β, and β-catenin signaling. Pembrolizumab with chemotherapy was feasible and resulted in PFS within the historical range for this EOC population. Patients with CPS ≥10 may benefit more from this regimen, and future studies should investigate this potential biomarker. This investigator-initiated trial was funded by Merck.

The Clinical Significance of CRNDE Gene Methylation, Polymorphisms, and CRNDEP Micropeptide Expression in Ovarian Tumors.

CRNDE is an oncogene expressed as a long non-coding RNA. However, our team previously reported that the CRNDE gene also encodes a micropeptide, CRNDEP. The amino acid sequence of CRNDEP has recently been revealed by other researchers, too. This study aimed to investigate genetic alterations within the CRNDEP-coding region of the CRNDE gene, methylation profiling of this gene, and CRNDEP expression analysis. All investigations were performed on clinical material from patients with ovarian tumors of diverse aggressiveness. We found that CRNDEP levels were significantly elevated in highly aggressive tumors compared to benign neoplasms. Consistently, a high level of this micropeptide was a negative, independent, prognostic, and predictive factor in high-grade ovarian cancer (hgOvCa) patients. The cancer-promoting role of CRNDE(P), shown in our recent study, was also supported by genetic and epigenetic results obtained herein, revealing no CRNDEP-disrupting mutations in any clinical sample. Moreover, in borderline ovarian tumors (BOTS), but not in ovarian cancers, the presence of a single nucleotide polymorphism in CRNDE, rs115515594, significantly increased the risk of recurrence. Consistently, in BOTS only, the same genetic variant was highly overrepresented compared to healthy individuals. We also discovered that hypomethylation of CRNDE is associated with increased aggressiveness of ovarian tumors. Accordingly, hypomethylation of this gene's promoter/first exon correlated with hgOvCa resistance to chemotherapy, but only in specimens with accumulation of the TP53 tumor suppressor protein. Taken together, these results contribute to a better understanding of the role of CRNDE(P) in tumorigenesis and potentially may lead to improvements in screening, diagnosis, and treatment of ovarian neoplasms.

Targeting estrogen metabolism in high-grade serous ovarian cancer shows promise to overcome platinum resistance

The high mortality rate due to chemoresistance in patients with high-grade ovarian cancer (HGSOC) emphasizes the urgent need to determine optimal treatment strategies for advanced and recurrent cases. Our study investigates the interplay between estrogens and chemoresistance in HGSOC and shows clear differences between platinum-sensitive and -resistant tumors. Through comprehensive transcriptome analyzes, we uncover differences in the expression of genes of estrogen biosynthesis, metabolism, transport and action underlying platinum resistance in different tissues of HGSOC subtypes and in six HGSOC cell lines. Furthermore, we identify genes involved in estrogen biosynthesis and metabolism as prognostic biomarkers for HGSOC. Additionally, our study elucidates different patterns of estrogen formation/metabolism and their effects on cell proliferation between six HGSOC cell lines with different platinum sensitivity. These results emphasize the dynamic interplay between estrogens and HGSOC chemoresistance. In particular, targeting the activity of steroid sulfatase (STS) proves to be a promising therapeutic approach with potential efficacy in limiting estrogen-driven cell proliferation. Our study reveals potential prognostic markers as well as identifies novel therapeutic targets that show promise for overcoming resistance and improving treatment outcomes in HGSOC.

Stimulator of Interferon Genes Protein (STING) Expression in Cancer Cells: A Tissue Microarray Study Evaluating More than 18,000 Tumors from 139 Different Tumor Entities.

Stimulator of interferon genes protein (STING) activates the immune response in inflammatory cells. STING expression in cancer cells is less well characterized, but STING agonists are currently being evaluated as anticancer drugs. A tissue microarray containing 18,001 samples from 139 different tumor types was analyzed for STING by immunohistochemistry. STING-positive tumor cells were found in 130 (93.5%) of 139 tumor entities. The highest STING positivity rates occurred in squamous cell carcinomas (up to 96%); malignant mesothelioma (88.5%-95.7%); adenocarcinoma of the pancreas (94.9%), lung (90.3%), cervix (90.0%), colorectum (75.2%), and gallbladder (68.8%); and serous high-grade ovarian cancer (86.0%). High STING expression was linked to adverse phenotypes in breast cancer, clear cell renal cell carcinoma, colorectal adenocarcinoma, hepatocellular carcinoma, and papillary carcinoma of the thyroid (p < 0.05). In pTa urothelial carcinomas, STING expression was associated with low-grade carcinoma (p = 0.0002). Across all tumors, STING expression paralleled PD-L1 positivity of tumor and inflammatory cells (p < 0.0001 each) but was unrelated to the density of CD8+ lymphocytes. STING expression is variable across tumor types and may be related to aggressive tumor phenotype and PD-L1 positivity. The lack of relationship with tumor-infiltrating CD8+ lymphocytes argues against a significant IFN production by STING positive tumor cells.

Seromucinous borderline tumor-associated high-grade ovarian cancers

We present 6 high grade ovarian carcinomas that were associated with seromucinous borderline tumors. Patients ranged in age from 26 to 66 years. All cancers appeared as solid regions within otherwise paucicystic tumors that measured from 4.2 cm to 14.0 cm in greatest dimension. Five of the 6 tumors were bilateral, and endometriosis was seen in 4 of the tumors. Clinical data, with follow up periods ranging from 0 to 40 months, was available for all patients. Four patients died of their disease and two had recurrent disease at the time of this review. All tumors exhibited a low-grade carcinoma component, which is consistent with ovarian cancers developing in a progressive adenoma to carcinoma sequence (so-called type I ovarian cancers). Two of the associated low-grade/borderline tumors had focal serous characteristics with WT1+ epithelial cell clustering. High-grade tumors exhibited an array of cell types expressing endometrioid, undifferentiated, serous, clear cell, and mucinous features that were at times mixed within the same tumor. Five cancers were focally WT1+; two showed admixed lowgrade serous features and one showed a high-grade serous adenocarcinoma with transitional features. Two cancers had mucinous features (one with focal CK20 and CDX2 immunohistochemical staining and one only with focal CDX2 immunohistochemical staining). All the high-grade tumors showed a mutated-pattern of p53 nuclear staining with &gt;75% 2-3+ staining. We conclude that seromucinous borderline tumors need to be extensively sampled. Cyst wall membrane rolls are important to evaluate since they may reveal persisting endometriosis and solid regions most likely harbor a high-grade tumor. Identifying high-grade cancer within a seromucinous borderline tumor is important because, although seromucinous borderline tumors and their oftassociated low-grade endometrioid cancers have favorable outcomes, tumors harboring a high-grade component are aggressive and may eventuate in patient death.

Quantifiable TCR repertoire changes in prediagnostic blood specimens among patients with high-grade ovarian cancer

High-grade ovarian cancer (HGOC) is a major cause of death in women. Early detection of HGOC usually leads to a cure, yet it remains a clinical challenge with over 90% HGOCs diagnosed at advanced stages. This is mainly because conventional biomarkers are not sensitive enough to detect the microscopic yet metastatic early lesions. In this study, we sequence the blood Tcell receptor (TCR) repertoires of 466 patients with ovarian cancer and controls and systematically investigate the immune repertoire signatures in HGOCs. We observe quantifiable changes of selected TCRs in HGOCs that are reproducible in multiple independent cohorts. Importantly, these changes are stronger during stage I. Using pre-diagnostic patient blood samples from the Nurses' Health Study, we confirm that HGOC signals can be detected in the blood TCR repertoire up to 4 years preceding conventional diagnosis. Our findings may provide the basis for future immune-based HGOC early detection criteria.