Citations

Abstract: A 21-year-old African American Division 1 female sprinter presented with 3-weeks history of right great toe and forefoot pain, fatigue, and a 30-day continuous menstrual cycle despite implanted etonogestrel (Nexplanon) inserted 3 years prior. An magnetic resonance imagine (MRI) identified likely stress fracture of the second metatarsal base with a diffusely low T1 signal indicating hyperactive red marrow. Due to persistent pain, a follow-up MRI was ordered 6 months later and indicated serous atrophy of the bone marrow, prompting a further metabolic workup notable for triglycerides exceeding 4000 mg/dL and a hemoglobin A1c of 10.9%. This case highlights the manifestation of a rare congenital lipodystrophy that initially presented as a relatively classic stress fracture and metrorrhagia in a female athlete.

AbstractIntroductionMelanoma guidelines stem largely from data on non‐Hispanic White (NHW) patients. We aimed to identify features of melanoma within non‐Hispanic Black (NHB) patients to inform strategies for earlier detection and treatment.MethodsFrom 2004 to 2019 Surveillance, Epidemiology, and End Results (SEER) data, we identified nonmetastatic melanoma patients with known TN category and race. Kaplan–Meier cancer‐specific survival (CSS) estimates and multivariable Cox proportional hazard modeling analyses were performed.ResultsOf 492 597 patients, 1499 (0.3%) were NHB, who were younger (21% vs. 17% age <50) and more commonly female (54% vs. 41%) than NHW, both p < 0.0005. For NHBs, lower extremity was the most common site (52% vs. 15% for NHWs, p < 0.0001), T category was higher (55% Tis–T1 vs. 82%; 27% T3–T4 vs. 8%, p < 0.0001) and stage at presentation was higher (19% Stage III, vs. 6%, p < 0.0001). Within the NHB cohort, males were older, and more often node‐positive than females. Five‐year Stage III CSS was 42% for NHB males versus 71% for females, adjusting for age and clinical nodal status (hazard ratio 2.48).ConclusionsNHB melanoma patients presented with distinct tumor characteristics. NHB males with Stage III disease had inferior CSS. Focus on this high‐risk patient cohort to promote earlier detection and treatment may improve outcomes.

Abstract Ovarian cancer is the most fatal of all female reproductive cancers due to its late detection, aggressive nature, and propensity to develop resistance to current standards of care. Despite initial responses to first line platinum- and paclitaxel-based chemotherapies, &gt;70% of ovarian cancers recur with increasingly resistant disease. Targeted therapies, including PARP-inhibitors (PARPi) and VEGF-inhibitors, are being included in the front-line setting; and while they have improved progression-free survival in a subset of patients, they have thus far failed to improve overall survival in patients without specific genetic signatures. With the broad uptake of PARPi, PARPi-resistance is becoming common. Once resistance develops, nearly all patients die of their disease and there is an obvious need to elucidate the basis for chemotherapy- and PARPi-resistance and devise novel approaches to overcome resistance. Using a small molecule drug screen, we identified lestaurtinib, a known tyrosine kinase inhibitor as a potent inhibitor of treatment naive and highly advanced models of ovarian cancer. Lestaurtinib was originally developed to target FLT3, a protein not expressed in any ovarian cancer models we’ve tested. To identify lestaurtinib targets, we preformed phospho-proteomics in parallel with RNAseq and discovered the JAK/STAT signally pathway as a top hit. We confirmed that essential components of JAK/STAT signaling are constitutively activated in chemotherapy- and PARPi-resistant cells, suggesting that induction of this pathway may drive resistance. Importantly, we found that lestaurtinib-sensitive patient-derived-xenografts (PDXs) exhibited higher expression of multiple JAK/STAT signaling pathway members compared to PDXs that did not respond to lestaurtinib. Genetic knockdown of STAT1 and STAT3 via siRNA, or knockout via CRISPR/Cas9, resulted in significant growth inhibition of sensitive and resistant models, confirming their importance in maintaining cell viability and progression. Combining lestuartinib with standard-of-care cisplatin or olaparib, a PARPi, was shown to be synergistic in multiple models, indicating that pharmacological inhibition of JAK/STAT signaling has the potential to alleviate drug resistance. Finally, we assessed a panel of JAK/STAT inhibitors that interfere at various levels of the pathway and found profound differences in their ability to block STAT-phosphorylation and inhibit cell proliferation. Thus, it is critical to further define the mechanisms by which these drugs function to selectively suppress JAK/STAT signaling in order to elucidate specific nodes of the pathway that drive ovarian cancer progression. Ongoing studies are aimed at identifying the unique roles of STAT1 and STAT3, the specific contributions of their tyrosine and serine phosphorylation, and the relevance of up-/down-stream mediators of the JAK/STAT pathway on ovarian cancer cell growth with the goal of informing future clinical trials. Citation Format: Esther Rodman, Michael Emch, Archit Bajaj, Xiaojia Tang, Xiaonan Hou, Scott Kaufmann, Krishna Kalari, John Weroha, John Hawse. Exploiting JAK/STAT signaling to inhibit highly advanced and resistant forms of ovarian cancer [abstract]. In: Proceedings of the AACR Special Conference on Ovarian Cancer; 2023 Oct 5-7; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_2):Abstract nr B002.

Abstract Background: The kinases ataxia-telangiectasia-mutated-and-Rad3-related kinase (ATR), checkpoint kinase 1 (CHK1) and WEE1 participate in the response to replication stress. Inhibitors of ATR, WEE1, and CHK1 are being tested for antineoplastic activity as monotherapies and in combination with chemotherapy. Although these agents impair cell cycle checkpoints, fork stabilization, origin firing, and HR, little is known about the apoptotic pathways that are engaged and the critical mediators activating cell death mechanisms. The present study utilizes high-grade serous ovarian cancer (HGSOC) cell lines and patient-derived xenografts (PDXs) to understand the predominant apoptotic players and assess changes involved in the resistance setting after treatment with these inhibitors. Methods: HGSOC cell lines were examined for responses to ceralasertib (ATRi), prexasertib (CHK1i), or adavosertib (WEE1i) using colony forming assays, immunoblotting, and assays for apoptosis. To characterize the cell death networks after prexasertib treatment, RNA-seq analysis was performed in two representative cell lines. Mechanisms involved in acquired resistance and downstream changes in cell fate were evaluated by generating prexasertib- resistant HGSOC cell lines. Results: Irrespective of the homologous recombination (HR) status, ovarian cell lines, and PDXs underwent cell death during prolonged exposure at clinically achievable concentrations. CDC25A-CDK2 signaling was predictive of responsiveness in vitro and in vivo. The subsequent apoptotic response was c-Jun N-terminal kinases (JNK) dependent and involved engagement of mitochondrial pathways rather than the TNFa-induced death receptor-mediated apoptosis we recently described in acute leukemia (H. Ding, N. Vincelette, et al., Cancer Res. 81:2666-2678, 2021). Additionally, ovarian lines selected for CHK1i resistance failed to die in response to either ATRi or WEE1i but were sensitive to front-line therapy options, including carboplatin and PARP inhibitor. Conclusions: Unlike AML, death receptor-mediated apoptosis was not observed; instead, the primary mechanism of cell killing in HGSOC lines involves activation of the mitochondrial apoptotic pathway. Our findings identify the key cell death-initiating events that serve as measures of response to replication checkpoint inhibitors in ovarian cancer. Acquired resistance to these therapies is multifactorial and mainly involves failure to exacerbate the replication stress response. Citation Format: Annapoorna Venkatachalam, Cristina Correia, Kevin L. Peterson, Xiaonan Hou, Annabella R. Strathman, Paula A Schneider, Karen S. Flatten, Laura N. Duffield, Cordelia D. McGehee, Melissa C. Larson, Xue Meng, Nicole D Vincelette, Ann L. Oberg, Hu Li, John Weroha, Scott H Kaufmann. Transcriptomic insights reveal role of BCL2 proteins in replication checkpoint inhibitor response [abstract]. In: Proceedings of the AACR Special Conference on Ovarian Cancer; 2023 Oct 5-7; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_2):Abstract nr B012.

Abstract Even though it is known that the immune response is highly relevant in ovarian cancer (OC), as demonstrated by the strong association between tumor infiltration by CD8 T cells and overall survival in high grade serous ovarian cancer, immunotherapy has not yet benefited patients with this disease. Therefore, there is a critical unmet need to identify new therapeutic targets and approaches that will improve outcomes for women with resistant disease. We used a novel culture system that uses a two-step activation process to elicit tumor-specific Type 1 (tumor-killing) T cells from the peripheral blood of OC patients. Briefly, the T cells are stimulated over the first two days with GM-CSF, MUC1 peptide antigens, and Toll-like receptor agonists (TLRa). After the second day in culture, the cells are washed and cultured in media containing IL-7 for the next 17 days. Using peripheral blood mononuclear cells (PBMCs) from 4 ovarian cancer patients, who had undergone between 1-3 prior lines of therapy, we have shown that all 4 were successfully activated and expanded with MUC1 antigens. Overall, the CD3+ cell population expanded from 5.7 – 12.6 fold over the 19 day culture, which was consistent with the sample from a healthy donor. Intracellular cytokine staining for IFNγ was used to determine MUC1-specific T cell responses at day 19. All OC patient T cells had increased reactivity to the MUC1-peptides as compared to the negative control peptide. Total MUC1-specificity ranged from 9.6 – 30.1% in CD4+ T cells and 6.6 – 16.8% in CD8+ T cells. We additionally performed high-parameter mass cytometry by time of flight (CyTOF) analysis using 34 antibodies targeting surface and intracellular markers. The FlowSOM algorithm followed by Marker Enrichment Modeling were used to identify major clusters of T cells and their associated phenotypes. Using this approach 12 major clusters of T cells were identified and overlayed on a tSNE plot. Of the 12 clusters, 7 represented CD8+ T cells and 5 represented CD4+ T cells. The day 19 clusters primarily represented T effector cells, T effector memory, and T central memory cells. The majority of day 19 cells expressed markers of effector function, including T-bet, EOMES, GRANZ-B, and GRANZ-K, which were present in both CD8+ and CD4+ populations. Exhaustion and regulatory markers were found to be low or absent in the day 19 cells. These results demonstrate that highly polyfunctional T cells with memory markers are generated from our innovative culture system using PBMCs from OC patients. These results provide preclinical evidence that will support future clinical trials of adoptive cell therapy using this culture system in OC. Citation Format: Brenda Ernst, Latha Pathangey, Michael Gustafson, Sandra Gendler, Marion Curtis. Rapid expansion of natural, MUC1-activated T cells from the peripheral blood of ovarian cancer patients for adoptive cell therapy [abstract]. In: Proceedings of the AACR Special Conference on Ovarian Cancer; 2023 Oct 5-7; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_2):Abstract nr A086.

Abstract Background: Prior infection with Chlamydia trachomatis, indicated by the presence of circulating antibodies against plasmid encoded glycoprotein 3 (Pgp3), is associated with an increased risk of ovarian cancer. The aberrant expression of p53 can be found in up to 95% of ovarian cancers and is an especially frequent feature among high-grade serous cancers. Prior studies have described mechanisms by which Chlamydia reprogram DNA damage response pathways, including those involving p53. However, tumor level expression of p53 among women with and without prior exposure to chlamydia is poorly described. We evaluated whether the association between prior chlamydial infection (Pgp3 seropositivity) and ovarian cancer varied by tumor p53 expression and whether Pgp3 seropositivity was associated with ovarian tumor expression of p53. Methods: Available serologic data for Pgp3 in tubo-ovarian cancer cases (n=155) and matched controls (n=556) from the Polish Ovarian Cancer Study were evaluated and stratified by p53 mutation status of cases inferred from immunohistochemical staining. Expression of p53 was assessed in tissue microarrays (2+ cores per case) and classified as aberrant (i.e., no expression or overexpression: ≥60% positive cells) or wild- type. Multinomial logistic regression with controls as the reference was used to estimate odds ratios (OR) and 95% confidence intervals (CI) for the association of Pgp3 seropositivity with ovarian cancer with stratification by p53 expression among the cases. Logistic regression among cases was only used to evaluate the association between Pgp3 and aberrant p53 expression. Results: Aberrant p53 expression was found in 70% of cases. Pgp3 seropositivity was associated with increased ovarian cancer risk (OR [95% CI]: 1.86 [1.28-2.68]). Pgp3 seropositivity was associated with risk for both p53 aberrant (1.79 [1.16-2.75]) or p53 wild-type ovarian cancers (2.06 [1.11-3.80], p for heterogeneity=0.80). When restricted to high-grade serous cancers, the association with Pgp3 was also not differential by p53 status (p for heterogeneity=0.16; 83% of high-grade serous cases had aberrant p53 expression). Among women with cancer, Pgp3 seropositivity was not associated with aberrant p53 expression (versus wild-type, OR [95% CI]: 0.90 [0.45-1.81], spearman correlation: -0.05, p-value=0.55). Conclusion/Discussion: Our study provides support that previous C. trachomatis infection is associated with ovarian cancer, irrespective of aberrant p53 tumor expression. There are many possible mechanisms by which Chlamydia may influence ovarian cancer. While the current results do not rule out interactions with p53-related pathways, it is likely that C. trachomatis increases ovarian cancer risk via multiple mechanisms (e.g., infection related sequelae like chronic inflammation). Citation Format: Sarina Pollat, Nicolas Wentzensen, Tim Waterboer, Manila Hada, Jolanta Lissowska, Beata Peplonska, Mark E. Sherman, Kara A. Michels, Britton Trabert. Prior chlamydial infection and ovarian cancer risk by tumor p53 expression [abstract]. In: Proceedings of the AACR Special Conference on Ovarian Cancer; 2023 Oct 5-7; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_2):Abstract nr A051.

Introduction and importance: Reports are limited on video-assisted thoracoscopic surgery for lung malignancy of patients with situs inversus totalis (SIT). Patients with SIT have significant anatomic differences with implications that are important for surgery, anesthesia, and nursing to understand in order to provide care for this patient population. Case presentation: A 64-year-old man with SIT and lung adenocarcinoma needed flexible bronchoscopy and wedge resection of a 9×8 mm adenocarcinoma in the right upper lobe and underwent video-assisted thoracoscopic surgery. Clinical discussion: Preoperative planning, including collaboration with the surgical team, allowed safe monitoring, induction of anesthesia, and airway isolation in this patient allowing them to have successful resection of their pulmonary malignancy. Postoperative care was enhanced by detailed communication and understanding of the patient’s anatomy and implications of this condition for post anesthesia care unit nursing care. Conclusion: Patients with rare clinical conditions and backgrounds may require surgical and anesthetic intervention. The authors describe important anesthetic considerations of preoperative evaluation, airway management, cardiac monitoring, and vascular access that should be noted and taken into account for patients with SIT. Proper preparation, planning, and communication allow for patients with SIT to safely undergo surgical procedures.

Abstract Introduction: Identifying dysregulated gene expression in ovarian cancers has been limited by a deficit of available normal tissues. Here, we generated the largest set of high-grade serous ovarian cancer (HGSOC) tumors with normal precursor tissues for transcriptome analyses to identify lncRNA expression patterns, provide insight into their cellular contexts and functions, and assess their relevance to HGSOC pathogenesis and genetic susceptibility. Methods: We performed RNA sequencing on 220 primary HGSOCs and 116 benign epithelia (micro-dissected fallopian tube, ovarian surface, and inclusion cyst epithelia), and combined samples with 428 HGSOCs from TCGA, 60 HGSOCs from a prior study, and 180 bulk ovary tissues from GTEx. Reads were processed with a uniform bioinformatic and quality control pipeline, combined and batch corrected. Normalized TPM expression values were compared using the Wilcoxon rank sum test with &gt;2-fold change and FDR &lt;1% considered statistically significant. We computed weighted gene co-expression networks for each tissue type and tested for enrichment of differentially expressed genes (DEGs) and gene ontologies within co-expression modules. Results: Transcriptomes included 27,700 expressed genes (8,202 lncRNAs) across 706 HGSOCs, 180 bulk ovary, and 88 ovarian epithelia tissues. Most genes were expressed in all tissues, though 5% each showed HGSOC- or normal tissue-specific expression which comprised ≥50% lncRNA. Comparing HGSOCs to normal tissues identified 11,804 DEGs with 4,522 lncRNAs (DElncRNA) of which ~50% were tissue-specific. DEGs included MUC16 and multiple GWAS/TWAS implicated susceptibility genes including RAD51, BRIP1, BNC2, TIPARP-AS1, PRC1, KANSL1, ANKLE1, CHMP4C, ESRP2, and CCNE1. The most highly expressed DElncRNA in HGSOC were upregulated RMRP (P=1.4 × 10−39), SNHG1 (P=3.0 × 10−27), and HAGLR (P=2.0 × 10−24) at the HOXD risk locus. Lower proportions of lncRNA were seen in the HGSOC co-expression modules compared to those in normal tissues and less (3% vs. 15%) HGSOC modules were considered strongly lncRNA regulated (&gt;50% lncRNA in module). Tissue-specific DElncRNA tended toward upregulation in HGSOC compared to ovarian epithelia with enriched modules associated with cell cycle regulation (P=1.5 × 10−38); and toward downregulation in HGSOC compared to bulk ovary with enriched modules associated with chemokine signaling/response (P=1.7 × 10−113). Conclusions: The lower proportion of lncRNA involved in HGSOC co-expression networks indicates a marked loss of regulation by lncRNA. Preliminary interrogation of HGSOC-dysregulated lncRNA expression revealed tissue-specific differences that highlight unique biological pathways in precursor epithelia and the ovarian microenvironment that contribute to HGSOC pathogenesis. Our results provide additional support for previously nominated risk genes. eQTL analysis has recently been completed and integration with GWAS are underway to elucidate lncRNA and lncRNA-regulated susceptibility genes and will be presented at the conference. Citation Format: Brett M. Reid, Ann Chen, Zhihua Chen, Florian A. Karreth, Peter Kanetsky, Jennifer B. Permuth, Ozlen Saglam, Jamie K. Teer, Xiaoqing Yu, Simon Gayther, Ellen Goode, Paul Pharoah, Thomas A. Sellers, Kate Lawrenson, Jonathan Tyrer. Patterns of lncRNA-regulated gene expression in high-grade serous ovarian carcinomas [abstract]. In: Proceedings of the AACR Special Conference on Ovarian Cancer; 2023 Oct 5-7; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(5 Suppl_2):Abstract nr A004.