Citations

Abstract Background: Acquired PARP inhibitor (PARPi) resistance in high-grade serous ovarian cancer (HGSOC) as a result of restored homologous recombination has been observed following secondary mutations that restore full-length protein in BRCA1, BRCA2, RAD51C, and RAD51D. Additionally, loss of BRCA1 methylation has also been shown to confer resistance. However, little is known about the role of RAD51C methylation in acquired PARPi resistance. In ARIEL2 Part 1, a phase 2 study of the PARPi rucaparib in ovarian carcinoma, four (2%) tumors demonstrated RAD51C methylation. The present study utilizes HGSOC patient derived xenografts (PDXs) and recurrent samples from ARIEL2 to assess the role of RAD51C methylation in the development of PARPi resistance. Methods: To drive PARPi resistance, PDX039, an extremely PARPi-sensitive model lacking demonstrable mutations in DNA repair genes, was treated cyclically with niraparib (100 mg/kg) for 21 days, after which the tumor was allowed to regrow and re-established in new mice for the next treatment round. To evaluate the frequency of methylation change, RAD51C methylation was analyzed in 12 rucaparib-treated mice (300 or 450 mg/kg) harboring PDX183, a PARPi-sensitive model without mutations in DNA repair genes. Global changes in gene expression following development of PARPi resistance were assessed by RNA sequencing. RAD51C promoter methylation was evaluated by bisulfite sequencing. Subsequent functional analysis included qRT-PCR, IHC, and western blot. DNA damage response pathways are being evaluated by immunofluorescence ex vivo following niraparib, rucaparib, or IR. Results: PDX039 grew through PARPi treatment by the third and fourth cycle of therapy. RAD51C was the only DNA repair gene to show significant change in RNAseq analysis (log2 fold-change=8.43; p=2e-192), corresponding with a loss of RAD51C methylation. Moreover, after just one round of PARPi treatment, RAD51C methylation was lost in 1 of 12 PARPi-treated PDX183 xenografts. RAD51C methylation loss ultimately resulted in restoration of expression, for which functional analysis is ongoing. Analysis of patient samples is currently underway. Conclusions: In HGSOC PDX models, RAD51C methylation affords PARPi sensitivity in the absence of DNA repair gene mutations. Treatment pressure with PARPi can reverse RAD51C methylation and restore RAD51C expression. Isolated changes in methylation of the RAD51C locus are sufficient to restore HR and convey PARPi resistance. Citation Format: Rachel M. Hurley, Ksenija Nesic, Cordelia McGehee, Olga Kondrashova, Maria I. Harrell, Paula A. Schneider, Xiaonan Hou, Cristina Correia, Karen S. Flatten, Giada V. Zapparoli, Alexander Dobrovic, Kevin K. Lin, Thomas C. Harding, Andrea E. Wahner Hendrickson, Elizabeth M. Swisher, Matthew Wakefield, S. John Weroha, Clare L. Scott, Scott H. Kaufmann. Loss of RAD51C promoter hypermethylation confers PARP inhibitor resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 5885.

Abstract Multiple myeloma (MM) is twice as common in African Americans (AA) compared to European Americans (EA). The reported familial clustering and the elevated MM risk among first-degree relatives of cases implicate genetic susceptibility. Previous genome-wide association studies (GWAS) in EA have identified 16 novel risk loci. In this study, we tested the generalizability of the established risk alleles to AA and conducted a meta-GWAS analysis using two sets of AA to identify additional novel common MM risk variants. In the first study, we genotyped 1,305 incident AA MM cases from the African American Multiple Myeloma Study (AAMMS) using the Illumina HumanCore GWAS array and compared them to 7,078 AA controls from the African Ancestry Prostate Cancer Consortium (AAPC) and African Ancestry Breast Cancer Consortium (AABC) using the Illumina 1M-Duo. In the second study, 95 additional AAMMS cases and 435 AA MM cases from the University of Arkansas for Medical Sciences (UAMS) were genotyped using the Illumina MegaBead Chip and compared to 2,390 AA controls from the Multiethnic Cohort. The Haplotype Reference Consortium (HRC) was used to impute the overlapping typed SNPS from each GWAS case and control set together. Per-allele risk associations were tested for 8,715,278 overlapping genotyped and imputed variants with >1% frequency and >0.8 imputation score using unconditional logistic regression in both sets, and the combined effects were estimated using a fixed-effect meta-analysis. Of the 16 reported risk loci discovered in EA, directional consistency was present for 15 variants; eight of these replicated at nominal significance p<0.05, with the most statistically significant variant being rs4487645 at 7p15.3 (OR=1.38, p=3.56×10-6). AA individuals with polygenic risk scores from these 16 variants (PRS) in the top 10% stratum had a 1.44-fold increased MM risk compared to those with a PRS in the 25th -75th percentiles. Additionally, we identified three suggestive novel loci located at 12q12, 9p24.3 and 9p13.1 at p<1×10-6, with ORs ranging from 1.25-1.55, but none reached genome-wide significance. The variant at 9p24.3 is located in an intron in the KANK1 gene and a correlated SNP in EAs (r2=0.5) is strongly associated with gene expression in neoplastic plasma cells (unpublished, Weinhold and Morgan). Our study replicated most of the reported risk loci discovered among EA, demonstrated that a PRS constructed using the 16 reported risk alleles was associated with MM risk, and provides suggestive evidence for additional loci associated with MM risk in AAs. Citation Format: Zhaohui Du, Chi Song, Kristin Rand, Niels Weinhold, David Van Den Berg, Amie Hwang, Xin Sheng, Victor Hom, Sikander Ailawadhi, Ajay K. Nooka, Seema Singhal, Karen Pawlish, Edward S. Peters, Cathryn Bock, Ann Mohrbacher, Alexander Stram, Sonja I. Berndt, William Blot, John David Carpten, Antoinette Stroup, Andrew Olshan, Wei Zhang, African Ancestry Breast & Prostate Consortium, Stephen Chanock, Jayesh Mehta, Graham A. Colditz, Jeffrey Wolf, Thomas G. Martin, Michael Tomasson, Mark A. Fiala, Howard Terebelo, Nalini Janakiraman, Laurence Kolonel, Loic LeMarchand, Elad Ziv, Daniel Stram, Ravi Vij, Leon Bernal-Mizrachi, Gareth J. Morgan, Jeffrey A. Zonder, Carol Ann Huff, Sagar Lonial, Robert Z. Orlowski, David V. Conti, Christopher A. Haiman, Wendy Cozen. A meta-analysis of genome-wide association studies of multiple myeloma among African Americans [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 223.

Abstract The endosteal niche is a component of the bone marrow microenvironment that can serve to protect hematological malignancies such as acute myeloid leukemia (AML) from standard chemotherapies such as cytarabine (Ara-C). Surviving AML cells harbored by this niche can eventually lead to relapse. The endosteal niche is rich in osteoblast lineage cells. U937 or KG1a AML cell lines were cultured with or without osteoblast lineage cells (MC3T3 or W-20-17 cell lines), challenged with doses of 0µM, 0.1µM, 0.5µM, 1µM, 5µM, or 10µM of Ara-C, and assayed for apoptosis via annexin-V staining and flow cytometry. Osteoblast lineage cells (MC3T3 or W-20-17 cell lines) were able to protect AML cells (U937 or KG1a cell lines) from Ara-C-induced apoptosis. Histone deacetylase inhibitors (HDACi) globally alter gene expression within cells. When we pre-treated osteoblast lineage cells (MC3T3) with the HDACi vorinostat (suberoylanilide hydroxamic acid, SAHA), it reduced the ability of the osteoblast lineage cells (MC3T3) to protect AML cells (U937) from Ara-C-induced apoptosis, which we have previously confirmed in the KG1a AML cell line as well. This indicates that osteoblast lineage cell-mediated protection of AML from Ara-C occurs via an HDACi sensitive mechanism. To begin to further explore the mechanism of action, we co-cultured AML cells (KG1a or U937) with and without osteoblast lineage cells (MC3T3) in the presence or absence of a transwell. We found that the presence of the transwell reduced the osteoblast lineage cell-mediated protection, indicating that osteoblast lineage cell-mediated protection of AML from Ara-C is cell contact dependent. Thus, osteoblast lineage cells can protect AML cells from Ara-C induced apoptosis, this protection can be reduced by pre-treatment of the osteoblast lineage cells with the HDACi vorinostat, and osteoblast lineage cell-mediated protection from Ara-C is cell contact dependent. These studies begin to characterize the mechanisms of osteoblast lineage cell-mediated protection of AML from Ara-C. Manipulating the protective properties of osteoblast lineage cells of the endosteal niche may help make AML cells more susceptible to chemotherapeutics. Therefore, developing combination therapies that target the protective mechanisms of osteoblast-lineage cells may help to further deplete the bone marrow microenvironment of AML cells and prevent relapse of disease. Citation Format: Rosalie M. Sterner, Kimberly N. Kremer, Meagan R. Rollins, Amel Dudakovic, Jennifer J. Westendorf, Andre J. van Wijnen, Karen E. Hedin. Osteoblast-lineage cells protect AML cells from cytarabine-induced apoptosis via a mechanism sensitive to HDACi and reduced cell-cell contact [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2137.

Screening for hepatopulmonary syndrome (HPS) using pulse oximetry is recommended in liver transplant (LT) candidates because mortality is increased, independently of the severity of the oxygenation defect. LT exception points may be afforded to those with HPS and severe hypoxemia. We assessed the screening characteristics of pulse oximetry for HPS. The Pulmonary Vascular Complications of Liver Disease 2 study is a multicenter, prospective cohort study of adults undergoing their first LT evaluation. Patients underwent protocolized assessment of oxygen saturation by pulse oximetry (SpO2), arterial blood gas, spirometry, and contrast‐enhanced echocardiography (CE). HPS was defined as an alveolar‐arterial gradient ≥15 mm Hg (≥20 mm Hg if age >64 years), intrapulmonary vascular dilatation on CE, and absence of lung disease. The study sample included 363 patients. Of these, 75 (20.7%; 95% confidence interval [CI], 16.6%‐25.2%) met the criteria for HPS. The area under the receiver operating characteristic curve (or c‐statistic) for SpO2 in discriminating HPS was 0.59 (95% CI, 0.51‐0.66). An SpO2 <96%, recommended by practice guidelines as a threshold to require further testing, had low sensitivity (28%; 95% CI, 18%‐28%). The c‐statistic of SpO2 in discriminating HPS with a partial pressure of oxygen (PaO2) <60 mm Hg (eligible for LT exception points) was 0.76 (95% CI, 0.46‐1.00). An SpO2 cutoff of <96% had higher sensitivity for detecting HPS with PaO2 <60 mm Hg (71%; 95% CI, 38%‐100%) but was still inadequate. Conclusion: Pulse oximetry is not sufficiently sensitive to screen for HPS in LT candidates. Arterial blood gas and CE are required in LT candidates for diagnosis of HPS.

BACKGROUNDDelirium is associated with poor outcomes in adults but is less extensively studied in children.OBJECTIVESTo describe a quality improvement initiative to implement delirium assessment in a pediatric intensive care unit and to identify barriers to delirium screening completion.METHODSA survey identified perceived barriers to delirium assessment. Failure modes and effects analysis characterized factors likely to impede assessment. A randomized case-control study evaluated factors affecting assessment by comparing patients always assessed with patients never assessed.RESULTSDelirium assessment was completed in 57% of opportunities over 1 year, with 2% positive screen results. Education improved screening completion by 20%. Barriers to assessment identified by survey (n = 25) included remembering to complete assessments, documentation outside workflow, and “busy patient.” Factors with high risk prediction numbers were lack of time and paper charting. Patients always assessed had more severe illness (median Pediatric Index of Mortality 2 score, 0.90 vs 0.36; P &lt; .001), more developmental disabilities (moderate to severe pediatric cerebral performance category score, 54% vs 32%; P = .007), and admission during lower pediatric intensive care unit census (median [interquartile range], 10 [9–12] vs 12 [10–13]; P &lt; .001) than did those never assessed (each group, n = 80). Patients receiving mechanical ventilation were less likely to be assessed (41.0% vs 51.2%, P &lt; .001).CONCLUSIONSSuccessful implementation of pediatric delirium screening may be associated with early use of quality improvement tools to identify assessment barriers, comprehensive education, monitoring system with feedback, multidisciplinary team involvement, and incorporation into nursing workflow models.

Aims: First, describe how acute myocardial infarction criteria are used to diagnose type 1 (T1MI) and 2 (T2MI) myocardial infarction. Second, determine whether subjective or objective criteria are used for T2MI. Third, examine outcomes for T2MI based on the presence or absence of objective evidence of myocardial ischemia compared with myocardial injury. Methods and results: Post-hoc analysis of UTROPIA (NCT02060760), a prospective, observational, cohort study involving 1640 consecutive emergency department patients with serial high-sensitivity cardiac troponin I among whom 74 (4.5%) had T1MI, 103 (6.3%) T2MI, and 245 (15%) myocardial injury. Compared with T1MI, patients with T2MI were less likely to have ischemic symptoms (97% vs. 83%), Q waves (24% vs. 1%), new ST-T wave changes (74% vs. 51%), new regional wall motion abnormality (64% vs. 11%), and a culprit lesion on coronary angiography (59% vs. 0%) (all p <0.05). T2MIs were more likely to be diagnosed using subjective criteria (symptoms alone) than T1MI (42% vs. 12%, p <0.0001). Patients with objective T2MI, but not subjective T2MI, had a two-fold increase in early mortality compared with myocardial injury, with 30- and 60-day hazard ratios (95% confidence interval) of 2.3 (0.9, 6.2) and 2.0 (0.9, 4.7) respectively. Conclusions: Among patients with T2MI, many cases are diagnosed using subjective criteria. The presence of objective evidence of myocardial ischemia may identify a higher-risk group of T2MI patients in whom early outcomes are worse than myocardial injury. Emphasis on using objective evidence of myocardial ischemia to diagnose T2MI may result in a more precise and specific disease definition.

Background: Underrepresentation of African American women as research participants contributes to health disparities. Contemporary studies have focused on clinical trial (CT) participation; epidemiologic and genetic studies utilizing medical records and/or biological samples have received less attention. In partnership with The Links, Incorporated (The Links), a national service organization of professional African American women, this study sought to examine attitudes regarding chart review (CR) studies, genetic studies/biobanking (GEN), and CTs; develop; and evaluate an online education-to-action program. Methods: In phase 1, focus groups were convened with members of The Links to inform the content and format of the program. Phases 2 and 3 involved designing and evaluating the program, respectively. Results: Thirty-four women across three focus groups shared attitudes and perceptions regarding research and provided guidance for program development. Subsequently, 244 women completed the program (77% response rate), including pre- and post-assessments. Participants indicating that they “definitely” or “probably” (responses combined) intend to participate in research increased from 36.5% to 69.3% (pre/post-program). Agreement with the statement “research in the U.S. is ethical” increased (52.9% to 74.4%) as did factual knowledge regarding each of the study types. There was a decrease in reporting “little or no understanding” of study types (Pre/Post: GEN: 66%/24.9%, CR: 62.9%/18.4%, CTs: 40.7%/15.5%). Pre-program, few were “very positive” about the study types (14.3% GEN, 15.0% CR, 28.6% CTs); post-program ratings increased and equalized (42.8% GEN, 43.0% CR, 42.5% CTs). Conclusions: An online education-to-action program targeting professional African American women improved knowledge, perceptions of ethics, and intent to participate in biomedical research.

Purpose: Novel approaches are needed to enhance employee well-being and perhaps supervisors can be an effective agent for worksite health promotion. The aim of this study was to examine the supervisor’s perceived needs, barriers, and role for influencing employee well-being for incorporation into program development. Design: Semistructured, qualitative interviews of supervisors. Setting: Large, integrated academic health-care organization with over 30 000 employees and 2600 supervisors having access to comprehensive well-being programs and a successful well-being champion network comprised of 600 champions. Participants: Twenty supervisors representing clinical, research, and administrative units. Methods: Semistructured, one-on-one interviews were conducted and audio recorded. Analysis included content log development and open coding by a trained analyst to reveal key themes. More formalized content coding using specialized software for qualitative analyses was also conducted. Results: Supervisor responses were wide ranging regarding their perceived and desired role in promoting workplace well-being. Barriers from the supervisor perspective included high current workload, ambivalence about promoting wellness, lack of support from leadership, lack of flexibility and control at work, and difficulty accessing on-site resources. They perceived their potential role in well-being as remaining a positive role model and encouraging their staff in wellness activities. Conclusion: Although findings are generated from a small sample size, these qualitative data provide compelling and early insights into building a workplace well-being strategy leveraging an underutilized key stakeholder, the workplace supervisor.

AbstractIntroductionType 2 diabetes mellitus and obesity may increase risks for cognitive decline as individuals age. It is unknown whether this results in different prevalences of cognitive impairment for women and men.MethodsThe Action for Health in Diabetes, a randomized controlled clinical trial of a 10‐year intensive lifestyle intervention, adjudicated cases of cross‐sectional cognitive impairment (mild cognitive impairment or dementia) 10–13 years after enrollment in 3802 individuals (61% women).ResultsThe cross‐sectional prevalences of cognitive impairment were 8.3% (women) and 14.8% (men): adjusted odds ratio 0.55, 95% confidence interval [0.43, 0.71], P < .001. Demographic, clinical, and lifestyle risk factors varied between women and men but did not account for this difference, which was limited to individuals without apolipoprotein E (APOE)‐ε4 alleles (interaction P = .034).ConclusionsAmong overweight and obese adults with type 2 diabetes mellitus, traditional risk factors did not account for the lower prevalence of cognitive impairment observed in women compared with men.