Citations

TPS4142 Background: Advanced cholangiocarcinoma (CC) is a life-threatening disease for which there are limited therapeutic options. Mutations in isocitrate dehydrogenase 1 (mIDH1) occur in up to 25% of intrahepatic CC cases. mIDH1 lead to epigenetic and genetic changes that promote oncogenesis via production of the oncometabolite, D-2-hydroxyglutarate (2-HG). AG-120 is a first-in-class oral inhibitor of the mIDH1 enzyme, and is being tested in a phase 1 study that enrolled 73 patients (pts) with mIDH1 CC who had received a median of 2 prior therapies (range 1–5). AG-120 has demonstrated a favorable safety profile and clinical activity in this study. Among the 72 efficacy evaluable pts (≥1 post-baseline response assessment or discontinued prematurely), 6% (n = 4) had a confirmed partial response and 56% (n = 40) had stable disease. Progression-free survival (PFS) rate at 6 months was 40% as of Dec 16, 2016. The 500 mg once daily (QD) dose of AG-120 was selected for the ongoing phase 3 study in mIDH1 CC described here. Methods: ClarIDHy is a global, phase 3, multicenter, double-blind study randomizing 186 pts with mIDH1 CC in a 2:1 ratio to AG-120 (500 mg QD) or matched placebo (NCT02989857). Key eligibility criteria: nonresectable or metastatic CC; documented mIDH1 based on central laboratory testing; ECOG 0–1; measurable disease (RECIST v1.1); documented disease progression following ≤2 prior systemic therapies in the advanced setting, including at least 1 gemcitabine- or 5-fluorouracil-containing regimen; and no prior mIDH inhibitor therapy. Crossover from the placebo arm to the AG-120 arm will be permitted. The primary endpoint is PFS as assessed by an independent review. Secondary endpoints include safety, tolerability, overall response rate, overall survival, pharmacokinetic and pharmacodynamic analyses on plasma, and quality of life as assessed by the EORTC QLQ-C30, EORTC QLQ-BIL21, and EQ-5D-5L instruments. An independent data monitoring committee will monitor the data throughout the study. The ClarIDHy study is currently activated at participating sites in the US and will be activated in centers throughout Europe and in South Korea. Clinical trial information: NCT02989857.

TPS3102 Background: Multiple myeloma (MM) is largely incurable despite available therapies, including immunomodulatory drugs (IMiDs), proteasome inhibitors (PIs), and monoclonal antibodies (mAbs). As most MM patients (pts) eventually have relapsed/refractory (RR) disease, there is an unmet need. Myeloma cells upregulate PD-L1 [Liu et al, 2007]. Nivolumab (nivo), an immuno-oncology mAb, binds PD-1 on T cells and natural killer cells and inhibits signaling by PD-L1–expressing tumor cells, thus augmenting antitumor immunity. Nivo monotherapy has shown acceptable safety and modest clinical activity in RRMM [Lesokhin et al 2016]. Daratumumab (dara) is a cytolytic mAb that targets CD38+ myeloma cells, inducing antibody‐dependent cellular cytotoxicity, complement-dependent cytotoxicity, antibody-dependent cellular phagocytosis, and apoptosis, and may have an immunomodulatory role via depletion of CD38+ immune-suppressor cells [Dimopoulos et al 2016]. Dara is approved as monotherapy (US: after ≥3 prior lines of therapy; EU: after a prior PI and IMiD and progression on last therapy), and with lenalidomide/dexamethasone (dex) or bortezomib/dex (US: after ≥1 prior line of therapy for both combinations). Combining PD-1 and CD38 mAbs, immunotherapies with different mechanisms of action, may overcome resistance and improve outcomes. This phase 1 safety study (NCT01592370) includes multiple cohorts of nivo as monotherapy or in combination regimens across RR hematologic malignancies; 2 MM cohorts will evaluate nivo plus dara, with or without pomalidomide and dex. Methods: Eligible pts are aged ≥18 y, with RRMM after ≥2 prior therapies. Pts are RR to their last regimen, RR to prior IMiD and PI therapy, and agreed to bone marrow aspiration. Primary outcome of safety/tolerability will be measured by incidence of drug-related adverse events (AEs), serious AEs, and laboratory test abnormalities. Secondary endpoints include minimal residual disease, overall response rates and duration of response, and progression-free survival. Study funding: BMS. Writing support: C Tomas, Caudex, funded by BMS. Clinical trial information: NCT01592370.

Mesenchymal stem cells (MSCs) constitute an important repair system, but may be impaired by exposure to cardiovascular risk factors. Consequently, adipose tissue-derived MSCs from pigs with the metabolic syndrome (MetS) show decreased vitality. A growing number of microRNAs (miRNAs) are recognized as key modulators of senescence, but their role in regulating senescence in MSC in MetS is unclear. We tested the hypothesis that MetS upregulates in MSC expression of miRNAs that can serve as post-transcriptional regulators of senescence-associated (SA) genes. MSCs were collected from swine abdominal adipose tissue after 16 weeks of Lean or Obese diet ( n = 6 each). Next-generation miRNA sequencing (miRNA-seq) was performed to identify miRNAs up-or down-regulated in MetS-MSCs compared with Lean-MSCs. Functional pathways of SA genes targeted by miRNAs were analyzed using gene ontology. MSC senescence was evaluated by p16 and p21 immunoreactivity, H2AX protein expression, and SA-β-Galactosidase activity. In addition, gene expression of p16, p21, MAPK3 (ERK1) and MAPK14, and MSC migration were studied after inhibition of SA-miR-27b. Senescence biomarkers were significantly elevated in MetS-MSCs. We found seven upregulated miRNAs, including miR-27b, and three downregulated miRNAs in MetS-MSCs, which regulate 35 SA genes, particularly MAPK signaling. Inhibition of miR-27b in cultured MSCs downregulated p16 and MARP3 genes, and increased MSC migration. MetS modulates MSC expression of SA-miRNAs that may regulate their senescence, and the p16 pathway seems to play an important role in MetS-induced MSC senescence.

Abstract The amplified MYCN gene serves as an oncogenic driver in approximately 20% of high-risk pediatric neuroblastomas. Here we show that c-MYC itself is a potent transforming gene in a separate subset of high-risk neuroblastoma cases (~10%), based on (i) its upregulation by focal enhancer amplification or genomic rearrangements leading to enhancer hijacking, and (ii) its ability to transform neuroblastoma precursor cells in a transgenic animal model. The aberrant regulatory elements associated with oncogenic c-MYC activation include focally amplified distal enhancers or translocation of highly active enhancers from other genes to within topologically associating domains containing the c-MYC gene locus. The clinical outcome for patients with high levels of c-MYC expression is virtually identical to that of patients with amplification of the MYCN gene, a known high-risk feature of this disease. Together, these findings establish c-MYC as a bona fide oncogene in a clinically significant group of high risk childhood neuroblastomas. Citation Format: Mark W. Zimmerman, Yu Liu, Shuning He, Adam D. Durbin, Brian J. Abraham, John Easton, Ying Shao, Xu Beisi, Shizhen Zhu, Xiaoling Zhang, Zhaodong Li, Nina Weichert-Leahey, Richard A. Young, Jinghui Zhang, A. Thomas Look. c-MYC drives a subset of high-risk pediatric neuroblastoma and is activated through mechanisms including enhancer hijacking and focal enhancer amplification [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 4135.

Abstract Background: Targeted therapies are increasingly under evaluation in clinical trials for the treatment of biliary tract cancer (BTC), and cell-free tumor DNA assays are an emerging technology for the detection of actionable alterations. Methods: ctDNA analysis was performed in patients with BTC using the CLIA-certified Guardant360 liquid biopsy assay as part of routine clinical care. The assay screens up to 73 genes for single-nucleotide variants (SNVs), 23 for insertions or deletions (INDELs), 18 for copy number variations (CNVs), and 6 for fusions. Results: 855 samples were analyzed from 751 unique BTC patients. Median age was 64 years (range, 29-89), 53% were female, and 631 (84%) had at least one alteration in their first sample. In the 751 patients, the most common genes altered were TP53 (39%), KRAS (15%), PIK3CA (13%), ARID1A (13%), EGFR (11%), FGFR2 (11%), ERBB2 (11%), NF1 (10%), IDH1 (10%), APC (9%), BRAF (9%), MYC (8%), MET (7%), CCNE1 (7%), and FGFR1 (7%). Alterations in DNA damage response genes were also seen, including BRCA2 (6%), BRCA1 (5%), ATM (4%), and MLH1 (1%). The median number of alterations per sample was 3 (range, 0-40). In a clinically annotated dataset from the Massachusetts General Hospital Cancer Center, 112 samples were obtained from 61 unique patients. Among these, 52 (85%) had intrahepatic cholangiocarcinoma (ICC), 3 (5%) had extrahepatic cholangiocarcinoma, and 6 (10%) had gallbladder cancer. 20/61 (33%) patients were treated with targeted therapy. Among 20 patients with both ctDNA and tumor sequencing results, the targetable mutation was found in both ctDNA and tumor tissue in 7/20 (35%), solely in ctDNA in 1/20 (5%), and solely in tissue in 12/20 (60%) patients. The patient with the alteration detected solely in ctDNA had insufficient tissue for analysis; she was found to have an FGFR2 F276C mutation and benefited for 8.5 months from an FGFR inhibitor on a clinical trial. Of the 12 patients whose targetable mutation was not detected in plasma, 10 (83%) had an FGFR2 fusion, 1 had an INDEL in FGFR2 (Leu262_Ala266delinsAsp), and 1 had an FGFR3 splice site mutation. 15/20 (75%) patients treated with targeted therapy were followed with serial ctDNA analysis, and a potential resistance mechanism was identified in 5/15 (33%). All 5 patients had FGFR2-fusion positive ICC and developed mutations in the FGFR2 kinase domain as a potential resistance mechanism to FGFR inhibition, including the FGFR2 V564F gatekeeper mutation in 4/5 patients. Conclusions: In patients with BTC, ctDNA-based genomic profiling can detect alterations in IDH, FGFR, PIK3CA, ERBB2, BRAF, and MET. The technology is still evolving for the detection of FGFR2 fusions, which is hindered in capture-based methods in plasma by the large number of unique breakpoints and fusion partners. ctDNA analysis may also provide a noninvasive mechanism to study resistance to targeted therapy and clonal dynamics in BTC. Citation Format: Lipika Goyal, Robin Kate Kelley, Lesli Kiedrowski, Daniel Catenacci, Kabir Mody, Rachna Shroff, Aparna Parikh, Stephanie Reyes, Jordan R. Maurer, Ryan B. Corcoran, Paul Fanta, Mike Cusnir, Becky Nagy, Richard Lanman, Michael Morse, Benjamin Tan, Milind Javle, Andrew Zhu. Blood-based genomic profiling of cell-free tumor DNA (ctDNA) in patients with biliary tract cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2017 Oct 26-30; Philadelphia, PA. Philadelphia (PA): AACR; Mol Cancer Ther 2018;17(1 Suppl):Abstract nr A183.

The use of supraglottic airway devices such as the King LTS-D laryngeal tube has increased in the prehospital setting because of their relative ease of successful insertion, even in the hands of inexperienced providers. However, these devices have their own associated complications. In patients with a known or suspected difficult airway, supraglottic airway device exchanges should occur under controlled conditions using an airway exchange catheter, preferably under direct visualization with a flexible fiberoptic bronchoscope. We report unanticipated difficulties with supraglottic airway exchange caused by a kinked King LTS-D laryngeal tube.

Background: Extracellular vesicles (EVs) released from mesenchymal stem/stromal cells (MSCs) mediate their paracrine effect, but their efficacy to protect the microcirculation of the kidney is unknown. Using a novel swine model of unilateral renovascular disease (RVD) complicated by metabolic syndrome (MetS), we tested the hypothesis that EVs would attenuate renal microvascular loss. Methods: Four groups of pigs ( n = 7 each) were studied after 16 weeks of diet-induced MetS and RVD (MetS+RVD), MetS+RVD treated 4 weeks earlier with a single intra-renal delivery of EVs harvested from autologous adipose tissue-derived MSCs, and Lean and MetS Sham controls. Stenotic-kidney renal blood flow (RBF) and glomerular filtration rate (GFR) were measured in-vivo (fast CT), whereas EV characteristics, renal microvascular architecture (micro-CT), and injury pathways were studied ex-vivo. Results: mRNA sequencing and proteomic analysis revealed that EVs are packed with several pro-angiogenic genes and proteins, such as vascular endothelial growth factor. Labeled EVs were detected in the stenotic kidney 4 weeks after injection internalized by tubular and endothelial cells. EVs restored renal expression of angiogenic factors and improved cortical microvascular and peritubular capillary density. Renal apoptosis, oxidative stress, tubular injury, and fibrosis were also attenuated in EV-treated pigs. RBF and GFR decreased in MetS+RVD compared with MetS, but normalized in MetS+RVD+EVs. Conclusions: Intra-renal delivery of MSC-derived EVs bearing pro-angiogenic properties restored the renal microcirculation and in turn hemodynamics and function in chronic experimental MetS+RVD. Our study suggests a novel therapeutic potential for MSC-derived EVs in restoring renal hemodynamics in experimental MetS+RVD.

Tendon injuries are among the most common and severe hand injuries with a high demand for functional recovery. Stem cells have been identified and isolated from different species and a variety of tissues for the sake of regenerative medicine. Recently, turkey has been suggested as a potential new large animal model for flexor tendon-related research. However, turkey tissue-specific stem cells have not been investigated. Here, we presented the isolation and verification of tendon-derived stem cells (TDSCs) from 6- to 8-month-old heritage-breed turkey. TDSCs were isolated from turkey flexor tendon by plating nucleated cells at the determined optimal density. Approximately 4% of the nucleated cells demonstrated clonogenicity, high proliferation rate, and trilineage differentiation potential after induction culturing. These cells expressed surface antigens CD90, CD105, and CD44, but did not express CD45. There was a high level of gene expression of tenogenic markers in TDSCs, including mohawk, collagen type I, tenascin C, and elastin. Turkey TDSCs also expressed transcription factorsPouV,Nanog, andSox2, which are critically involved in the regulation of stemness. The successful isolation of tendon-derived stem cells from turkey was beneficial for future studies in tendon tissue engineering and would help in the development of new treatment for tendon diseases using this novel animal model.