Armstrong, Deborah K.

Abstract Introduction: Epigenetic modulators may sensitize platinum-resistant ovarian cancer (PROC) to immune checkpoint inhibition by reprogramming the tumor microenvironment. Methods: We report clinical and translational findings from a phase II non-randomized study of pembrolizumab and oral azacitidine in 34 women with PROC (NCT02900560). Key eligibility criteria included age ≥ 18 years, ECOG performance status of 0-1, measurable disease and platinum-resistant, histologically confirmed epithelial ovarian cancer, fallopian tube carcinoma or primary peritoneal carcinoma. Primary endpoints included safety, tolerability, overall response rate (ORR), and disease control rate (DCR). Secondary endpoints included CA-125 response. The effect of combined epigenetic modulation and immunotherapy was evaluated by transcriptomic analyses of 72 serially biopsied tumors. Target gene expression analyses were used to identify differentially expressed genes and pathways, and bulk RNA sequencing was used for gene set enrichment analyses (GSEA) and to infer T cell receptor (TCR) assemblies. Results: The combination of azacitidine and pembrolizumab was moderately well tolerated, and the most common grade 3-4 adverse events were gastrointestinal side effects and anemia. ORR was 2.9% and DCR was 50%; with 3 of the 27 evaluable patients attaining a CA-125 response. Differential gene expression analyses revealed an upregulation of inflammatory and cytolytic genes (FDR-adjusted p=0.005) and co-inhibitory checkpoints (p=0.005) 6 weeks on-therapy. Upregulation of interferon signaling (p=0.006), antigen presentation (p=0.003), costimulatory signaling (p=0.002), and immune cell adhesion and migration (p=0.005) pathways were prominent on-therapy, together with an increase in CD8+ T-cell density (p=0.05). GSEA analyses were concordant with these findings, showing enrichment of immune and inflammatory gene sets on-therapy and upregulation of gene sets linked to IFN-γ response, natural killer cell-mediated cytotoxicity, and immunoregulatory interactions (p < 10e-13). Findings were not confounded by histological subtype. TCR abundance analyses evaluating significant TCR clonotypic expansions and regressions showed that intra-tumoral TCR repertoires were reshaped on-therapy. Furthermore, patients with a CA-125 and/or clinical response showed enrichment of hallmark inflammatory gene sets at baseline (p < 10e-10) and of adaptive and conserved immune response gene sets on therapy (p < 10e-09). Conclusions: Our findings highlight the potential of epigenetic modulators to reshape the tumor microenvironment of PROC toward a more inflammatory phenotype and may point to approaches to augment immunotherapy response. Citation Format: Blair V. Landon, Julia L. Boland, Andrea E. Wahner Hendrickson, Deborah K. Armstrong, Boris Winterhoff, Jaime Wehr, Akshaya V. Annapragada, Christopher Cherry, Archana Balan, Guneet Kaleka, Victor E. Velculescu, Stephen B. Baylin, Cynthia A. Zahnow, Dennis J. Slamon, Gottfried E. Konecny, John A. Glaspy, Valsamo (Elsa) Anagnostou. Pembrolizumab and epigenetic modification with azacitidine reprogram the tumor microenvironment of platinum-resistant epithelial ovarian cancer: clinical and translational findings from a phase II study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(8_Suppl):Abstract nr CT260.

Abstract Purpose: Germline alterations in homologous recombination repair (gHRR) genes affect the pathogenesis, treatment options, and survival of patients with cancer. However, distinct gHRR gene alterations may differentially affect treatment response and oncogenic signaling. In this study, we interrogated genomic and transcriptomic data and assessed clinical outcomes of patients with gHRR mutations across four BRCA-associated cancers (breast, ovarian, pancreatic, and prostate cancers) to identify therapeutic vulnerabilities. Experimental Design: We assessed 24,309 patients undergoing matched tumor/normal next-generation DNA and RNA sequencing. Annotated gHRR gene variants [germline BRCA1, germline BRCA2, germline PALB2, germline ATM (gATM), and germline CHEK2] were analyzed. HRs were used to assess survival outcomes comparing germline versus sporadic groups. Somatic alterations and their frequencies were compared across gHRR-altered groups. Differential gene expression and gene set enrichment analysis were used to compare transcriptomic profiles. Results: Somatic TP53 mutations were depleted in gATM carriers (P < 0.05) across all four BRCA-associated cancers by up to 2.5-fold. Tumors with germline BRCA1/2 mutations were associated with improved survival in patients with ovarian cancer and had consistent enrichment of TP53 mutations in all four cancers. gATM mutations displayed elevated p53 transcriptional activity in all four cancers, with significance reached in breast and prostate cancers (P < 0.01). In breast, ovarian, and prostate cancers, gATM tumors demonstrated significantly increased inflammatory pathways (P < 0.001). Finally, using gene dependency data, we found that cell lines that were highly dependent on ATM were co-dependent on canonical p53 function. Conclusions: gATM-associated cancers seem to require intact p53 activity and this synthetic essentiality may be used to guide targeted therapies that perturb canonical TP53 function.

ASCO Guidelines provide recommendations with comprehensive review and analyses of the relevant literature for each recommendation, following the guideline development process as outlined in the ASCO Guidelines Methodology Manual . ASCO Guidelines follow the ASCO Conflict of Interest Policy for Clinical Practice Guidelines . Clinical Practice Guidelines and other guidance (“Guidance”) provided by ASCO is not a comprehensive or definitive guide to treatment options. It is intended for voluntary use by clinicians and should be used in conjunction with independent professional judgment. Guidance may not be applicable to all patients, interventions, diseases or stages of diseases. Guidance is based on review and analysis of relevant literature and is not intended as a statement of the standard of care. ASCO does not endorse third-party drugs, devices, services, or therapies and assumes no responsibility for any harm arising from or related to the use of this information. See complete disclaimer in Appendix 1 and 2 (online only) for more . PURPOSE To provide updated guidance regarding neoadjuvant chemotherapy (NACT) and primary cytoreductive surgery (PCS) among patients with stage III-IV epithelial ovarian, fallopian tube, or primary peritoneal cancer (epithelial ovarian cancer [EOC]). METHODS A multidisciplinary Expert Panel convened and updated the systematic review. RESULTS Sixty-one studies form the evidence base. RECOMMENDATIONS Patients with suspected stage III-IV EOC should be evaluated by a gynecologic oncologist, with cancer antigen 125, computed tomography of the abdomen and pelvis, and chest imaging included. All patients with EOC should be offered germline genetic and somatic testing at diagnosis. For patients with newly diagnosed advanced EOC who are fit for surgery and have a high likelihood of achieving complete cytoreduction, PCS is recommended. For patients fit for PCS but deemed unlikely to have complete cytoreduction, NACT is recommended. Patients with newly diagnosed advanced EOC and a high perioperative risk profile should receive NACT. Before NACT, patients should have histologic confirmation of invasive ovarian cancer. For NACT, a platinum-taxane doublet is recommended. Interval cytoreductive surgery (ICS) should be performed after ≤four cycles of NACT for patients with a response to chemotherapy or stable disease. For patients with stage III disease, good performance status, and adequate renal function treated with NACT, hyperthermic intraperitoneal chemotherapy may be offered during ICS. After ICS, chemotherapy should continue to complete a six-cycle treatment plan with the optional addition of bevacizumab. Patients with EOC should be offered US Food and Drug Administration–approved maintenance treatments. Patients with progressive disease on NACT should have diagnosis reconfirmed via tissue biopsy. Patients without previous comprehensive genetic or molecular profiling should be offered testing. Treatment options include alternative chemotherapy regimens, clinical trials, and/or initiation of end-of-life care. Additional information is available at www.asco.org/gynecologic-cancer-guidelines . This guideline has been endorsed by the Society of Gynecologic Oncology.

The NCCN Guidelines for Ovarian Cancer/Fallopian Tube Cancer/Primary Peritoneal Cancer provide multidisciplinary diagnostic workup, staging, and treatment recommendations for this disease. These NCCN Guidelines Insights detail how the evolution of the use of PARP inhibitors as maintenance and single-agent regimens for the treatment of ovarian cancer informed panel recommendations in the guidelines.

Epithelial ovarian cancer is the leading cause of death from gynecologic cancer in the United States, with less than half of patients living >5 years following diagnosis. The NCCN Guidelines for Ovarian Cancer provide recommendations for the diagnosis, evaluation, treatment, and follow-up for patients with ovarian, fallopian tube, and primary peritoneal cancers. These NCCN Guidelines Insights summarize the panel discussion behind recent important updates to the guidelines, including revised guidance on alternative chemotherapy regimens for patients with advanced age and/or comorbidities, a new algorithm for recurrent low-grade serous carcinoma based on developing research and novel therapeutic agents, and updated language regarding tumor molecular analysis applications in ovarian cancer.

Epithelial ovarian cancer is the leading cause of death from gynecologic cancer in the United States and is the country’s fifth most common cause of cancer mortality in women. A major challenge in treating ovarian cancer is that most patients have advanced disease at initial diagnosis. These NCCN Guidelines discuss cancers originating in the ovary, fallopian tube, or peritoneum, as these are all managed in a similar manner. Most of the recommendations are based on data from patients with the most common subtypes─high-grade serous and grade 2/3 endometrioid. The NCCN Guidelines also include recommendations specifically for patients with less common ovarian cancers, which in the guidelines include the following: carcinosarcoma, clear cell carcinoma, mucinous carcinoma, low-grade serous, grade 1 endometrioid, borderline epithelial, malignant sex cord-stromal, and malignant germ cell tumors. This manuscript focuses on certain aspects of primary treatment, including primary surgery, adjuvant therapy, and maintenance therapy options (including PARP inhibitors) after completion of first-line chemotherapy.

Abstract Background: The combination of cediranib (ced) and olaparib (olap) improves progression-free survival and overall response rates (ORR) in women with recurrent plat sensitive high-grade serous (HGS) ovarian cancer compared to olap alone. In this Phase 2 study of ced/olap in women with relapsed ovarian cancer (NCT02345265), we observed an ORR of 74% with ced/olap in plat sensitive relapsed patients (pts) and an ORR of 20% in plat resistant pts. BROCA-HR was performed to characterize tumor HRD status and to correlate this with the activity of ced/olap in the plat sensitive and resistant settings. Methods: Pts with relapsed ovarian cancer across 11 centers were enrolled to 2 cohorts, either plat sensitive or resistant. All pts received ced 30mg daily and olap tablets 200mg BID. Archival, pre-treatment, and on-treatment biopsies were collected on all pts where safely feasible; pts also had the option of undergoing a post-progression biopsy. A baseline blood sample was collected for germline testing and matched control. Available samples were sequenced with BROCA-HR, and HRD status was determined by (1) presence of an HR-related mutation or (2) an increase in loss of heterozygosity (LOH) score. Results: 72 pts were enrolled, with 70 pts receiving study treatment (35 plat sensitive and 35 plat resistant). BROCA-HR analysis is complete on 60 samples, with 10 samples in final analysis. The concordance of HRD status by presence of an HR-related mutation or by LOH score was relatively low (agreement=36/60=60%, Cohen's Kappa=0.28). In 19 pts with a germline BRCA mutation, 16 were HRD+ by LOH (LOH high), 2 were HRD- by LOH (LOH low), and 1 not quantifiable. 3 pts had a somatic BRCA mutation; 1 was LOH high, 1 LOH low, and 1 not quantifiable. 4 pts had non-BRCA somatic HR-related mutations (3 CDK12; 1 ATR); 3 were LOH high and 1 LOH low. Of the 34 pts without HR-related mutations, 15 were LOH high, 16 were LOH low, and 3 not quantifiable. In 29 plat sensitive pts with BROCA-HR results, 18 were HRD+ by mutation (12 germline BRCA, 3 somatic BRCA, 3 somatic other), and 16 were HRD+ by LOH (LOH high). The ORR in plat sensitive pts by HRD status with available HRD results was: 22/29=75.9% (13/18=72% HRDmut+; 9/11=82% HRDmut-); (12/16=75% LOH high; 6/9= 67% LOH low). In 31 plat resistant pts with BROCA-HR results, 8 were HRD+ by mutation (7 germline BRCA, 0 somatic BRCA, 1 somatic other), and 19 were HRD+ by LOH. The ORR in plat resistant pts by HRD status with available HRD results was: 7/31=22.6% (4/8=50% HRDmut+; 3/23=13% HRDmut-, P=0.05); (7/19=37% LOH high; 0/11= 0% LOH low, P=0.03). Updated results with the full data set are pending. Conclusion: Ced/olap has clinical activity in women with relapsed ovarian cancer, both in the plat sensitive and plat resistant settings. In women with plat sensitive disease, where response rates are high, HRD status by presence of an HR-related mutation or LOH status does not appear to provide significant additional information regarding likelihood of response. In women with plat resistant disease, the presence of HRD by an HR-related mutation or LOH status is correlated with a higher likelihood of response. Citation Format: Joyce F Liu, Su-Chun Cheng, Robert M Wenham, Andrea E Wahner Hendrickson, Deborah K Armstrong, Nancy Chan, David E Cohn, Jung-Min Lee, Richard T Penson, Mihaela Cristea, James Abbruzzese, Koji Matsuo, Alexander B Olawaiye, Jennifer Curtis, Geoffrey Shapiro, Ursula A Matulonis, Elise Kohn, Percy Ivy, Elizabeth M Swisher. Correlation of homologous recombination deficiency (HRD) status by BROCA-HR sequencing with response to combination cediranib and olaparib in relapsed ovarian cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr A074. doi:10.1158/1535-7163.TARG-19-A074

AbstractTopotecan (TPT) is a topoisomerase I (topo I) poison that has shown promising antineoplastic activity in solid tumors and acute leukemia. In the present study, a band depletion assay was used to evaluate the ability of TPT to stabilize topo I-DNA adducts in human leukemia cell lines and in clinical leukemia samples ex vivo. This assay showed that 50% of the cellular topo I in HL-60 human myelomonocytic leukemia cells became covalently bound to DNA at an extracellular TPT concentration of 4 μmol/L. In contrast, in 13 clinical specimens of human leukemia harvested before treatment of patients with TPT, the TPT concentration required to stabilize 50% of the cellular topo I in topo I-DNA complexes ranged from 3 to greater than 100 μmol/L (median, 30 μmol/L). Flow microfluorimetry showed that cellular TPT accumulation varied over only a twofold range and failed to provide evidence for transport-mediated resistance in the clinical samples. These observations raise the possibility that formation of topo I-DNA adducts is diminished in many specimens of refractory/relapsed acute leukemia by a mechanism that might alter topo I sensitivity to TPT.

Epithelial ovarian cancer is the leading cause of death from gynecologic cancer in the United States, with less than half of patients living >5 years from diagnosis. A major challenge in treating ovarian cancer is that most patients have advanced disease at initial diagnosis. The best outcomes are observed in patients whose primary treatment includes complete resection of all visible disease plus combination platinum-based chemotherapy. Research efforts are focused on primary neoadjuvant treatments that may improve resectability, as well as systemic therapies providing improved long-term survival. These NCCN Guidelines Insights focus on recent updates to neoadjuvant chemotherapy recommendations, including the addition of hyperthermic intraperitoneal chemotherapy, and the role of PARP inhibitors and bevacizumab as maintenance therapy options in select patients who have completed primary chemotherapy.