Citations

Abstract Neuroblastoma is an embryonal tumor arising in the peripheral sympathetic nervous system (PSNS), and often presents with widespread metastasis at diagnosis. We recently demonstrated that overexpression of LMO1 can synergize with MYCN to promote tumor metastasis in our zebrafish model system. Here, we identify a “metastasis suppressor” gene – growth arrest specific 7 (GAS7) – whose loss of function or reduced expression can promote dissemination and migration of neuroblastoma cells with MYCN overexpression, both in vitro and in vivo. GAS7 resides on chromosome 17p13.1, a region that is deleted in high-risk neuroblastomas with higher frequency in MYCN-amplified cases. Expression levels of GAS7 are also significantly downregulated in MYCN-amplified or otherwise MYCN-overexpressing human neuroblastoma cells, as well as MYCN-overexpressing zebrafish PSNS cells, suggesting an inverse relationship between the oncogenic activities of MYCN and GAS7downregulation. To determine whether loss of function or reduced expression of GAS7 could contribute to neuroblastoma pathogenesis in the context of MYCN overexpression, we developed a gas7 knockout zebrafish line using a transcription activator-like effector nucleases (TALEN) method. Loss of function of gas7 promoted hematogenous metastasis of MYCN-overexpressing tumor cells to tissues and organs that paralleled the common sites of metastasis in neuroblastoma patients. Further RNA-sequencing and qRT-PCR analyses showed that representative signature genes encoding proteins involved in tumor cell-cell or cell-extracellular matrix interactions were significantly downregulated in fish tumors with loss of function of gas7, consistent with our electron microscopic finding in the fish model showing a loss of contact among tumor cells in fish lacking functional gas7, suggesting that GAS7 may physically act as a metastasis suppressor. Thus, in high-risk neuroblastoma with MYCNamplification or overexpression, we propose that deletion or reduced expression of GAS7 cooperates with MYCN to promote neuroblastoma cell dissemination. Although the precise mechanism of this interaction remains unclear, we suggest that it relies, in part, on the downregulation of pivotal genes involved in tumor cell-cell or cell-extracellular matrix contacts. Citation Format: Zhiwei Dong, Gonzalo Lepez Garcia, Cheng Zhang, Erin N. Dankert, Jo Lynne Harenza, Xiaonan Hou, Hu Li, John M. Maris, Shizhen (Jane) Zhu. Loss of function of GAS7 promotes neuroblastoma metastasis in the context of MYCN overexpression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr LB-127.

AbstractAlterations in global DNA methylation patterns are a major hallmark of cancer and represent attractive biomarkers for personalized risk stratification. Chronic lymphocytic leukemia (CLL) risk stratification studies typically focus on time to first treatment (TTFT), time to progression (TTP) after treatment, and overall survival (OS). Whereas TTFT risk stratification remains similar over time, TTP and OS have changed dramatically with the introduction of targeted therapies, such as the Bruton tyrosine kinase inhibitor ibrutinib. We have shown that genome-wide DNA methylation patterns in CLL are strongly associated with phenotypic differentiation and patient outcomes. Here, we developed a novel assay, termed methylation-iPLEX (Me-iPLEX), for high-throughput quantification of targeted panels of single cytosine guanine dinucleotides from multiple independent loci. Me-iPLEX was used to classify CLL samples into 1 of 3 known epigenetic subtypes (epitypes). We examined the impact of epitype in 1286 CLL patients from 4 independent cohorts representing a comprehensive view of CLL disease course and therapies. We found that epitype significantly predicted TTFT and OS among newly diagnosed CLL patients. Additionally, epitype predicted TTP and OS with 2 common CLL therapies: chemoimmunotherapy and ibrutinib. Epitype retained significance after stratifying by biologically related biomarkers, immunoglobulin heavy chain mutational status, and ZAP70 expression, as well as other common prognostic markers. Furthermore, among several biological traits enriched between epitypes, we found highly biased immunogenetic features, including IGLV3-21 usage in the poorly characterized intermediate-programmed CLL epitype. In summary, Me-iPLEX is an elegant method to assess epigenetic signatures, including robust classification of CLL epitypes that independently stratify patient risk at diagnosis and time of treatment.

Objectives: Data are lacking regarding implementation of novel strategies such as follow-up clinics and peer support groups, to reduce the burden of postintensive care syndrome. We sought to discover enablers that helped hospital-based clinicians establish post-ICU clinics and peer support programs, and identify barriers that challenged them. Design: Qualitative inquiry. The Consolidated Framework for Implementation Research was used to organize and analyze data. Setting: Two learning collaboratives (ICU follow-up clinics and peer support groups), representing 21 sites, across three continents. Subjects: Clinicians from 21 sites. Measurement and Main Results: Ten enablers and nine barriers to implementation of “ICU follow-up clinics” were described. A key enabler to generate support for clinics was providing insight into the human experience of survivorship, to obtain interest from hospital administrators. Significant barriers included patient and family lack of access to clinics and clinic funding. Nine enablers and five barriers to the implementation of “peer support groups” were identified. Key enablers included developing infrastructure to support successful operationalization of this complex intervention, flexibility about when peer support should be offered, belonging to the international learning collaborative. Significant barriers related to limited attendance by patients and families due to challenges in creating awareness, and uncertainty about who might be appropriate to attend and target in advertising. Conclusions: Several enablers and barriers to implementing ICU follow-up clinics and peer support groups should be taken into account and leveraged to improve ICU recovery. Among the most important enablers are motivated clinician leaders who persist to find a path forward despite obstacles.

Abstract Objectives Pathogenic free-living amebae (FLAs) cause skin, ocular, and central nervous system (CNS) infections with significant morbidity and mortality. Diagnosis of FLA infections by pathologic examination of tissue sections can be aided using molecular assays. This study investigated the performance characteristics of a multiplex real-time polymerase chain reaction (PCR) assay (FLA-PCR) for detection and differentiation of FLAs in clinical specimens. Methods FLA-PCR was performed on 39 human specimens comprising one cutaneous, 14 corneal, and 24 CNS formalin-fixed, paraffin-embedded (FFPE) tissues with a histopathologic diagnosis of FLA infection and four CNS FFPE tissues with inflammation but no evidence of FLAs. In addition, clinical specificity and assay limit of detection were determined. Results FLA detection sensitivities ranged from 79% to 84% in FFPE tissues. No cross-reactivity was observed. Conclusions While sensitivity is limited, FLA-PCR assay may serve as a useful adjunct for detection or confirmation of FLA infections in FFPE tissues.

AbstractAn association between genetic variants in the vitamin D receptor (VDR) gene and epithelial ovarian cancer (EOC) was previously reported in women of African ancestry (AA). We sought to examine associations between genetic variants in VDR and additional genes from vitamin D biosynthesis and pathway targets (EGFR, UGT1A, UGT2A1/2, UGT2B, CYP3A4/5, CYP2R1, CYP27B1, CYP24A1, CYP11A1, and GC). Genotyping was performed using the custom‐designed 533,631 SNP Illumina OncoArray with imputation to the 1,000 Genomes Phase 3 v5 reference set in 755 EOC cases, including 537 high‐grade serous (HGSOC), and 1,235 controls. All subjects are of African ancestry (AA). Logistic regression was performed to estimate odds ratios (OR) and 95% confidence intervals (CI). We further evaluated statistical significance of selected SNPs using the Bayesian False Discovery Probability (BFDP). A significant association with EOC was identified in the UGT2A1/2 region for the SNP rs10017134 (per allele OR = 1.4, 95% CI = 1.2‐1.7, P = 1.2 × 10−6, BFDP = 0.02); and an association with HGSOC was identified in the EGFR region for the SNP rs114972508 (per allele OR = 2.3, 95% CI = 1.6‐3.4, P = 1.6 × 10−5, BFDP = 0.29) and in the UGT2A1/2 region again for rs1017134 (per allele OR = 1.4, 95% CI = 1.2‐1.7, P = 2.3 × 10−5, BFDP = 0.23). Genetic variants in the EGFR and UGT2A1/2 may increase susceptibility of EOC in AA women. Future studies to validate these findings are warranted. Alterations in EGFR and UGT2A1/2 could perturb enzyme efficacy, proliferation in ovaries, impact and mark susceptibility to EOC.

Summary Opioids have long held a prominent role in the management of perioperative pain in adults and children. Published reports concerning the appropriate, and inappropriate, use of these medications in pediatric patients have appeared in various publications over the last 50 years. For this document, the Society for Pediatric Anesthesia appointed a taskforce to evaluate the available literature and formulate recommendations with respect to the most salient aspects of perioperative opioid administration in children. The recommendations are graded based on the strength of the available evidence, with consensus of the experts applied for those issues where evidence is not available. The goal of the recommendations was to address the most important issues concerning opioid administration to children after surgery, including appropriate assessment of pain, monitoring of patients on opioid therapy, opioid dosing considerations, side effects of opioid treatment, strategies for opioid delivery, and assessment of analgesic efficacy. Regular updates are planned with a re‐release of guidelines every 2 years.