Citations

Abstract Medulloblastoma and central nervous system primitive neuroectodermal tumors (CNS-PNET) are aggressive, poorly differentiated brain tumors with limited effective therapies. Using Sleeping Beauty (SB) transposon mutagenesis, we identified novel genetic drivers of medulloblastoma and CNS-PNET. Cross-species gene expression analyses classified SB-driven tumors into distinct medulloblastoma and CNS-PNET subgroups, indicating they resemble human Sonic hedgehog and group 3 and 4 medulloblastoma and CNS neuroblastoma with FOXR2 activation. This represents the first genetically induced mouse model of CNS-PNET and a rare model of group 3 and 4 medulloblastoma. We identified several putative proto-oncogenes including Arhgap36, Megf10, and Foxr2. Genetic manipulation of these genes demonstrated a robust impact on tumorigenesis in vitro and in vivo. We also determined that FOXR2 interacts with N-MYC, increases C-MYC protein stability, and activates FAK/SRC signaling. Altogether, our study identified several promising therapeutic targets in medulloblastoma and CNS-PNET. Significance: A transposon-induced mouse model identifies several novel genetic drivers and potential therapeutic targets in medulloblastoma and CNS-PNET.

Abstract Retrospective studies have suggested that older adolescents and young adults (AYAs) with acute lymphoblastic leukemia (ALL) have better survival rates when treated using a pediatric ALL regimen administered by pediatric treatment teams. To address the feasibility and efficacy of using a pediatric treatment regimen for AYA patients with newly diagnosed ALL administered by adult treatment teams, we performed a prospective study, CALGB 10403, with doses and schedule identical to those in the Children's Oncology Group study AALL0232. From 2007 to 2012, 318 patients were enrolled; 295 were eligible and evaluable for response. Median age was 24 years (range, 17-39 years). Use of the pediatric regimen was safe; overall treatment-related mortality was 3%, and there were only 2 postremission deaths. Median event-free survival (EFS) was 78.1 months (95% confidence interval [CI], 41.8 to not reached), more than double the historical control of 30 months (95% CI, 22-38 months); 3-year EFS was 59% (95% CI, 54%-65%). Median overall survival (OS) was not reached. Estimated 3-year OS was 73% (95% CI, 68%-78%). Pretreatment risk factors associated with worse treatment outcomes included obesity and presence of the Philadelphia-like gene expression signature. Use of a pediatric regimen for AYAs with ALL up to age 40 years was feasible and effective, resulting in improved survival rates compared with historical controls. CALGB 10403 can be considered a new treatment standard upon which to build for improving survival for AYAs with ALL. This trial was registered at www.clinicaltrials.gov as #NCT00558519.

We aimed to assess the role of a short duration multimedia workshop to improve the knowledge and skills in cardiac critical care ultrasonography. Thirty critical care physicians participated in the cardiac critical care ultrasonography workshop. Two weeks prior to hands-on training, a three-hour web-based didactic lecture was provided to learners. Hands-on training consisted of a two-hour examination on models without pathology and a 30-minute debriefing with instructors. Pre- and post-workshop knowledge tests were conducted online using 30 multiple choice questions. Pre- and post-workshop skill tests were video captured for evaluation by two reviewers to whom data were masked. Scores were based on 34 predetermined checklist items including learner performance, instrumentation and adequacy of ultrasound images. Learners’ confidence levels on image acquisition were assessed using a ten-point Likert scale. A short duration multimedia, hands-on workshop improved intensivists’ knowledge, skills and confidence levels on cardiac critical care ultrasonography image acquisition. Further studies are needed to assess the sustainability of observed improvements. This module may be a practical option for the acquisition and maintenance of cardiac critical care ultrasonography knowledge and skills.

ABSTRACT Evaluating the association of multiple genetic variants with a trait of interest by use of kernel‐based methods has made a significant impact on how genetic association analyses are conducted. An advantage of kernel methods is that they tend to be robust when the genetic variants have effects that are a mixture of positive and negative effects, as well as when there is a small fraction of causal variants. Another advantage is that kernel methods fit within the framework of mixed models, providing flexible ways to adjust for additional covariates that influence traits. Herein, we review the basic ideas behind the use of kernel methods for genetic association analysis as well as recent methodological advancements for different types of traits, multivariate traits, pedigree data, and longitudinal data. Finally, we discuss opportunities for future research.

728 Background: Adjuvant FOLFOX therapy for stage II patients remains controversial, and selection criteria are imprecise. We examined the trend of disease-free survival (DFS: time to recurrence or death, whichever occurs first); time to recurrence (TTR: time to recurrence, censored at death without recurrence); survival after recurrence (SAR); and overall survival (OS) of pts treated with FOLFOX over a ten-year period. Methods: Outcomes of pts with stage II colon cancer enrolled in 6 adjuvant trials receiving FOLFOX alone were analyzed. Pt enrollment period was dichotomized as old (1998 – 2003) vs. new era (2004 – 2009) based on the FDA approval date of bevacizumab. 3/5yr event-free rates were estimated using adjusted Kaplan-Meier methods. Outcomes were compared between the two eras by multivariate Cox model. To control for potential confounding effects, all analyses were adjusted for age, gender, performance score, T stage, number of lymph nodes (LNs) examined, tumor side, and histologic grade. Results: In total, 1,122 pts with stage II were identified; 71% and 29% were treated in the old and new era, respectively. Pts enrolled in the new era were significantly younger and more likely to have higher tumor-grade and right-sided tumors compared to old era. More pts in the new era (71%) had ≥12 LNs examined compared to the old era (53%). After adjusting for potential confounding effects, no difference in DFS, TTR, SAR or OS between old and new eras was found (Table). Although median SAR increased from 13.6 to 26 months over time, this was not statistically significant, likely due to lack of power. An increased TTR over time (HRadj. 0.41, padj.= 0.002) was observed in pts with ≥12 LNs examined (3-yr TTR: 92% in old era vs. 96% in new era), but not pts with <12 LNs examined (pinteraction = 0.04). Conclusions: In stage II colon cancer pts who received adjuvant FOLFOX, no significant increase of DFS or OS was observed over time. However TTR was longer only in pts with ≥12 LNs examined. [Table: see text]

724 Background: Adjuvant FOLFOX is the standard of care for pts with stage III colon cancer and a platform to test new agents. Improvements in supportive care and development of newer treatments for metastatic disease impact the overall outcome of pts treated with adjuvant therapy. We examined the trend of disease-free survival (DFS), survival after recurrence (SAR), and overall survival (OS) of pts treated with FOLFOX over a ten-year period. Methods: Outcomes of colon cancer pts enrolled in 6 adjuvant trials receiving FOLFOX alone were analyzed. Pt enrollment period was dichotomized as old (1998 – 2003) vs. new era (2004 – 2009) based on the FDA approval date of bevacizumab. 3/5yr event-free rates were estimated by adjusted Kaplan-Meier methods. Outcomes were compared between the two eras by Cox model. To control for potential confounding effects, all analyses were adjusted for age, gender, performance score, T/N stage, tumor sidedness and histologic grade. Results: In total, 7,230 pts (stage II [n = 1122]; stage III [n = 6,108]) were identified; 32% and 68% were treated in the old and new era, respectively. Stage III pts enrolled in the new era were significantly younger, more likely to have T4/N2 disease, higher tumor grade, and left-sided tumors. After adjusting for pt characteristics, no difference in DFS was seen over time. However prolonged SAR and OS were observed in pts treated in the new era (Table). 5yr OS increased from 76% to 80% over time. Median SAR improved from 14.8 to 26.4 months. Conclusions: Stage III colon cancer pts who received adjuvant FOLFOX experienced significant improvements in SAR and OS—but not DFS—over time. In view of the improvements in OS and nearly doubled SAR, the optimal duration of OS follow-up to evaluate the benefits of adjuvant therapy (currently 5 years) should be reassessed, and ACCENT investigators are planning to conduct these additional analyses using their large pooled-trial database. [Table: see text]

723 Background: The US FDA approved pembro for treating pts with 1) recurrent locally advanced or metastatic G/GEJ adenocarcinoma, whose disease has progressed on or after ≥2 prior therapies and whose tumors express PD-L1 (combined positive score [CPS] ≥1), and 2) unresectable or metastatic, microsatellite instability-high (MSI-H) solid tumors that have progressed after prior therapy and who have no fitting options. We report Asian subgroup analyses from cohort 1 of KEYNOTE-059 (NCT02335411), a global, phase 2 study in advanced G/GEJ cancer. Methods: Eligible pts had measurable recurrent or metastatic G/GEJ adenocarcinoma whose disease has progressed on ≥2 prior chemotherapy regimens. Pts received pembro 200 mg Q3W up to 2 y. PD-L1+ tumors had a CPS ≥1. Primary end points were ORR (RECIST 1.1, by central review) and safety. Results: Cohort 1 enrolled 259 pts; 57% had PD-L1+ tumors. MSI status was evaluable in 174 tumor samples; of these, 7 were MSI-H. At data cutoff (4/21/2017), median (range) follow-up was 6 mo (1-25). Overall ORR was 12% (95% CI, 8-17) and median (range) DOR was 14 mo (2-19+). PFS6-mo rate was 15% and OS6-mo rate was 46%. In pts with PD-L1+ tumors, ORR was 16% (95% CI, 11-23) and median (range) DOR was 14 mo (3+-19+). In pts with PD-L1+ tumors, PFS6-mo rate was 20% and OS6-mo rate was 50%. In pts with MSI-H tumors, ORR was 57% (95% CI, 18-90) and median (range) DOR was not reached (5-14+ mo). In cohort 1, 41 pts were Asian and 218 pts were non-Asian. PD-L1+ tumors occurred in 42% of Asian pts and 60% of non-Asian pts. ORR was 12% (95% CI, 2-36) in Asian pts with PD-L1+ tumors and 17% (95% CI, 11-24) in non-Asian pts with PD-L1+ tumors. One of 7 pts with MSI-H tumors was Asian; this pt had CR. Grade 3-5 treatment-related AEs occurred in 17% and 18% of Asian and non-Asian pts, similar to the overall cohort. Conclusions: Pembro showed durable clinical benefit in previously treated pts with advanced G/GEJ cancer, especially those with PD-L1+ or MSI-H tumors. Safety and efficacy were similar in Asian and non-Asian pts. These findings highlight pembro as a standard treatment option in Asian and non-Asian pts with advanced G/GEJ cancer. Clinical trial information: NCT02335411.

The lack of reliable, noninvasive methods to diagnose early nonalcoholic steatohepatitis (NASH) is a major unmet need. We aimed to determine the diagnostic accuracy of three‐dimensional magnetic resonance elastography (3D‐MRE), with shear stiffness measured at 60 Hz, damping ratio at 40 Hz, and magnetic resonance imaging proton density fat fraction (MRI‐PDFF) in the detection of NASH in individuals undergoing bariatric surgery. Obese adults at risk for NASH were enrolled between 2015 and 2017 (prospective cohort, n = 88) and 2010 and 2013 (retrospective cohort, n = 87). The imaging protocol consisted of multifrequency 3D‐MRE (mf3D‐MRE) with shear waves delivered at different frequencies to explore parameters that best correlated with histologic NASH, and MRI‐PDFF to estimate steatosis. The prospective cohort was used to establish the optimal mf3D‐MRE technical parameters for NASH detection. The two cohorts were then combined to derive predictive models of NASH and disease activity by nonalcoholic fatty liver disease activity score (NAS) using the three imaging parameters that correlated with NASH. A total of 175 patients (median age 45, 81% women, and 81 [46%] with histologic NASH) were used for model derivation. From the complex shear modulus output generated by mf3D‐MRE, the damping ratio at 40 Hz and shear stiffness at 60 Hz best correlated with NASH. The fat fraction obtained from MRI‐PDFF correlated with steatosis ( P < 0.05 for all). These three parameters were fit into a logistic regression model that predicted NASH with cross‐validated area under the receiver operating characteristic curve (AUROC) = 0.73, sensitivity = 0.67, specificity = 0.80, positive predictive value = 0.73 and negative predictive value = 0.74, and disease activity by NAS with cross‐validated AUROC = 0.82. Conclusion: The mf3D‐MRE allows identification of imaging parameters that predict early NASH and disease activity. This imaging biomarker represents a promising alternative to liver biopsy for NASH diagnosis and monitoring. The results provide motivation for further studies in nonbariatric cohorts.

ABSTRACTFlexor tendon injury is often associated with suboptimal outcomes and results in substantial digit dysfunction. Stem cells have been isolated from several experimental animals for the growing interest and needs of utilizing cell‐based therapies. Recently, turkey has been developed as a new large animal model for flexor tendon research. In the present study, we reported the isolation and characterization of bone marrow‐derived mesenchymal stem cells (BMSCs) from 8‐ to 12‐month‐old heritage‐breed turkeys. The isolated cells demonstrated fibroblast‐like morphology, clonogenic capacity, and high proliferation rate. These cells were positive for surface antigens CD90, CD105, and CD44, but were negative for CD45. The multipotency of turkey BMSCs was determined by differentiating cells into osteogenic, adipogenic, chondrogenic, and tenogenic lineages. There was upregulated gene expression of tenogenic markers, including mohawk, tenomodulin, and EGR1 as well as increased collagen synthesis in BMP12 induced cells. The successful isolation and verification of bone marrow‐derived MSCs from turkey would provide opportunities of studying cell‐based therapies and developing new treatments for tendon injuries using this novel preclinical large animal model. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1419–1428, 2019.