Citations

AbstractBackgroundNeurodegeneration of the substantia nigra in dementia with Lewy bodies is associated with iron deposition, which increases the magnetic susceptibility of the substantia nigra on MRI. The objective of this study was to measure the magnetic susceptibility of the substantia nigra in patients with dementia with Lewy bodies (DLB) and patients with mild cognitive impairment with at least one core feature of DLB (MCI‐DLB) compared to cognitively unimpaired controls (CU) by quantitative susceptibility mapping (QSM).MethodWe studied clinically diagnosed patients with DLB (n=36), patients with MCI‐DLB (n=16), and age‐, gender‐matched CU (n=104) in a case‐control study. MR images used for QSM were performed on 3T MRI with a multi‐echo (5 echoes) 3D gradient recalled echo sequence with a bipolar‐readout. Three‐dimensional regions of interest (ROIs) of bilateral substantia nigra, based on the DISTAL atlas, were propagated from the Mayo Clinic Adult Lifespan Template (MCALT) to each subject’s T1 image using ANTs nonlinear registration. The mean susceptibility values of the substantia nigra were extracted by aligning each subjects QSM image to their T1 image and corresponding ROIs with a 6 DOF rigid registration.ResultThe mean susceptibility values of the substantia nigra bilaterally was 0.110 ± 0.026 for DLB, 0.099 ± 0.028 for MCI‐DLB and 0.091 ± 0.025 for controls (Figure 1). No difference was found across the mean susceptibility from left, right and combined bilateral substantia nigra. Compared to controls, patients with DLB had higher susceptibility in the substantia nigra (p<0.001). The susceptibility of substantia nigra showed an increasing trend from controls to MCI‐DLB and to DLB (p<0.001). There was no correlation between the Unified Parkinson's Disease Rating Scale (UPDRS) and the mean susceptibility in the substantia nigra in patients with MCI‐DLB and DLB (r=0.03; p=0.82).ConclusionQuantitative susceptibility mapping is sensitive to the increased magnetic susceptibility due to higher iron content in the substantia nigra in DLB. The trend of increasing susceptibility from CU to MCI‐DLB and to DLB suggests that iron deposition in the substantia nigra starts to increase as early as the prodromal stage in DLB and continues to increase as the disease progresses independent of the severity of Parkinsonism.

AbstractBackgroundThe critical‐period theory of menopausal hormone therapy (mHT) suggests that if menopausal hormone therapy begins shortly after menopause, it may have beneficial effects on brain structure and cognitive health. We investigated white matter integrity with diffusion tensor MRI (DTI) 3 years after the end of mHT trial in recently menopausal women who were randomized shortly after menopause.MethodParticipants of this study were enrolled in the Kronos Early Estrogen Prevention Study (aged 42–56 years; 5–36 months past menopause). Participants received the following treatments: 0.45 mg/d oral conjugated equine estrogen (oCEE, n=19); 50 μg/d transdermal 17β‐estradiol (tE2, n=22); or placebo (n=33) for 4 years. Oral progesterone (200 mg/d) was given to hormone therapy groups for 12 days each month. DTI was performed 3 years after the end of 4 years of hormone therapy (n=75), which corresponded to 7 years after randomization. Voxel‐based analysis was performed on DTI to evaluate fractional anisotropy (FA) and mean diffusivity (MD) differences between treatment groups (uncorrected p<0.001).ResultVoxel based analysis showed higher FA, a measure of white matter integrity, in the superior corona radiata, anterior limb of the internal capsule and splenium of the corpus callosum of participants treated with oCEE compared to placebo (p <0.001, Figure 1A). Furthermore, higher FA was observed in the superior corona radiata, anterior limb of internal capsule and thalamus in participants treated with tE2 compared to placebo (p <0.001, Figure 1B). There were no differences in FA findings between oCEE and tE2 groups, and no MD differences between treatments groups.ConclusionA relatively higher FA in a variety of white matter regions in the oCEE and tE2 groups compared to placebo suggest that mHT may have long‐term protective effects on white matter integrity. Previously, we had shown that women in the tE2 group preserved their dorsolateral prefrontal cortex volumes better than the placebo group over 7 years. Our findings suggest that the tracts that connect the dorsolateral prefrontal cortex and the thalamus such as the superior corona radiata and the anterior limb of internal capsule may particularly benefit from mHT.

AbstractBackgroundCharacterization of the changes that occur throughout the transition from asymptomatic to symptomatic for those with familial frontotemporal dementia is essential for planning future disease‐modifying trials.MethodWe identified four related microtubule associated protein tau (MAPT) N279K mutation carriers who have phenoconverted from the asymptomatic to the symptomatic state. Key features were as follows: Case 1 (female) initial exam age 36, onset age 44, current age 49; Case 2 (male) initial exam age 39, onset age 43, current age 48; Case 3 (female) initial exam age 41, onset age 47, current age 53; Case 4 (male) initial exam age 36, onset age 37, current age 46. MRI and neuropsychological data were analyzed.ResultStructural MRI was analyzed using Tensor Based Morphometry Symmetric Diffeomorphic Image Normalization (TBM‐SyN) methodology to quantify lobar volumes, which was then analyzed using a Mixed Effects Model to determine the annual change in lobar volumes. The phenoconverters had a greater estimated annual rate of cortical atrophy in temporal (p <0.001), frontal (p <0.01) and parietal (p <0.05) lobes compared to non‐carriers, with the rate of annual change in symptomatic individuals double that of asymptomatic individuals. Annual change in the parietal and occipital lobes was also analyzed and found to be similar to healthy controls of a similar age. Raw scores on neuropsychological measures were converted to z‐scores for analysis. Category fluency, letter fluency, and Trails A and B were all impaired (z‐score <‐1.5) following phenoconversion, but performance on these and other measures was variable across these four in the late asymptomatic state.ConclusionFor each of the four phenoconverters, structural MRI changes preceded symptom onset, whereas neuropsychological performance was more variable and occurred in closer proximity to the time of phenoconversion. Decrements in verbal fluency and cognitive flexibility were observed earlier than other cognitive domains. These findings suggest that changes in frontal and temporal volume on MRI precede symptom onset, with regional brain volumes most consistently tracking the evolution from the asymptomatic to symptomatic state in N279K MAPT mutation carriers. Supported by: AG063911, AG045390, NS092089, AG016976, AG016574, AG062677.

Background: The FMS-like tyrosine kinase 3 (FLT3) inhibitor gilteritinib (Gilt) improves survival compared with standard salvage chemotherapy in relapsed/refractory (R/R) FLT3-mutated (FLT3mut+) acute myeloid leukemia (AML); however, relapses are common and long-term survival remains poor. Combination therapies of FLT3 tyrosine kinase inhibitors (TKIs) with agents that induce apoptosis have demonstrated preclinical synthetic lethality and enhanced cytotoxicity against FLT3mut+ clones. This may delay or prevent drug resistance. We present updated data from the dose-escalation and expansion cohorts of an ongoing, multicenter, open-label, Phase 1b trial (NCT03625505) of Gilt in combination with B-cell lymphoma 2 (BCL-2) inhibitor venetoclax (Ven) in patients (pts) with R/R FLT3mut+ AML. Methods: Pts with R/R AML with ≥1 prior line of therapy and Eastern Cooperative Oncology Group (ECOG) performance status of 0-2 were eligible. The expansion cohort required FLT3mut+ R/R AML at enrollment. Pts received the recommended Phase 2 dose (RP2D) of Ven 400 mg in combination with Gilt 120 mg daily in 28-day cycles, following a 3-day ramp-up of Ven. Pts with prior Gilt were excluded from expansion, and none were enrolled in dose escalation; prior Ven or other FLT3 inhibitor was permitted. Concurrent use of moderate or strong CYP3A4 inhibitor was allowed. Interruptions of Ven or both drugs simultaneously were permitted for management of adverse events (AEs), and subsequent cycles could include dose adjustments to minimize myelosuppression or other drug-related AEs. The primary endpoint was modified composite complete remission (mCRc; complete response [CR] + CR with incomplete platelet recovery [CRp] + CR with incomplete blood count recovery [CRi]) + morphologic leukemia-free state (MLFS). Responses were graded by the International Working Group (IWG) for AML criteria (with adapted CRi criteria as presented in the ADMIRAL trial) for comparison with composite CR (CRc) used in Gilt development. All criteria for response used by IWG were maintained in these response definitions. Secondary endpoints included CR + CR with partial hematologic recovery (CRh) and duration of response (DOR) of mCRc. Results: At data cutoff, April 15, 2020, 39 R/R pts started therapy at the RP2D (internal tandem duplications [ITD] only [n=32]; tyrosine kinase domain [TKD] mutation only [n=5]; both TKD and ITD [n=2]). Median age was 63 years (range 23-85) and the majority had an ECOG status of 1-2 (87.2%). Most pts (n=29; 74.4%) had received ≥2 prior lines of therapy, including ≥1 FLT3 TKI (n=25, 64.1%; midostaurin, n=19; sorafenib, n=5; crenolanib, n=1). Twelve pts (30.8%) had prior stem-cell transplant (SCT); 3 (7.7%) had received prior Ven. Grade ≥3 treatment-emergent AEs (TEAEs) were reported in 37 pts (94.9%), and 28 (71.8%) reported serious AEs. The only Grade 3/4 nonhematologic TEAE reported in &gt;20% of pts was febrile neutropenia (48.7%). Four pts (10.3%) experienced a fatal AE, including colitis, disease progression, multiple organ dysfunction syndrome, and bronchopulmonary aspergillosis (all n=1). AEs leading to Ven and Gilt interruptions occurred in 19 pts (48.7%) and 18 pts (46.2%), respectively, and AEs leading to dose reductions occurred in 2 pts (5.1%) for each treatment. Six pts (15.4 %) and 5 pts (12.8%) discontinued Ven and Gilt, respectively, owing to AEs. mCRc was achieved by 83.8% of pts (n=31/37; Table). With median duration of follow-up of 2.9 (range 0.8−11.0) months in all pts, median event-free survival was 5.1 (95% confidence interval: 2.8, 8.3) months but administrative censoring after short follow-up for a large number of recently enrolled patients limits interpretation; median DOR has not been reached. Eight pts (21.6%), all ITD only, proceeded to SCT. CR + CRh was achieved by 7 pts (18.9%). Conclusions: Ven plus Gilt achieved a very high overall rate of marrow and blood blast elimination and mCRc rate (84%) in this expansion cohort of heavily pretreated FLT3mut+ pts, the majority of whom had prior FLT3 TKI exposure. Using similar response assessment criteria, the high mCRc rate here suggests substantially greater antileukemic activity from Ven plus Gilt compared with single-agent Gilt. Cytopenias were prominent but manageable with dose interruption/modification on subsequent cycles. Nonhematologic toxicities were modest, and the combination was well tolerated. Disclosures Daver: Bristol-Myers Squibb: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Pfizer: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Karyopharm: Research Funding; Servier: Research Funding; Genentech: Research Funding; AbbVie: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Astellas: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Novimmune: Research Funding; Gilead: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding; Trovagene: Research Funding; Fate Therapeutics: Research Funding; ImmunoGen: Research Funding; Novartis: Consultancy, Membership on an entity's Board of Directors or advisory committees; Celgene: Consultancy, Membership on an entity's Board of Directors or advisory committees; Jazz: Consultancy, Membership on an entity's Board of Directors or advisory committees; Trillium: Consultancy, Membership on an entity's Board of Directors or advisory committees; Syndax: Consultancy, Membership on an entity's Board of Directors or advisory committees; Amgen: Consultancy, Membership on an entity's Board of Directors or advisory committees; KITE: Consultancy, Membership on an entity's Board of Directors or advisory committees; Agios: Consultancy, Membership on an entity's Board of Directors or advisory committees; Daiichi Sankyo: Consultancy, Membership on an entity's Board of Directors or advisory committees, Research Funding. Altman:AbbVie: Membership on an entity's Board of Directors or advisory committees, Research Funding; Fujifilm: Research Funding; Astellas: Other: Advisory Board, Speaker (no payment), Steering Committee (no payment), Research Funding; Agios, Theradex, Abbvie: Other: Advisory Board; Astellas, Agios: Honoraria, Research Funding; Glycomimetics: Other: Data safety and monitoring committee; Daiichi Sankyo: Other: Advisory Board - no payment but was reimbursed for travel; Kura Oncology: Patents & Royalties: Scientific Advisory Board - no payment accepted; Biosight: Other: No payment but was reimbursed for travel . Levis:Menarini: Honoraria; Amgen: Honoraria; FujiFilm: Honoraria, Research Funding; Daiichi-Sankyo: Honoraria; Astellas: Honoraria, Research Funding. Ritchie:Abbvie: Honoraria; Sierra Oncology: Honoraria; Incyte: Speakers Bureau; Novartis: Honoraria; Jazz pharmaceuticals: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding. McCloskey:Amgen: Consultancy, Honoraria; BMS: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; AbbVie: Consultancy, Honoraria; Jazz: Consultancy, Honoraria. Smith:Abbvie: Other: Research Support, Research Funding; Sanofi: Honoraria; Astellas Pharma: Honoraria, Other: Research Support, Research Funding; FujiFilm: Other: Research support, Research Funding; Revolution Medicines: Other: Research Support, Research Funding; Daiichi Sanyko: Consultancy, Honoraria. Schiller:Johnson & Johnson: Current equity holder in publicly-traded company; Novartis: Consultancy, Research Funding; Sangamo: Research Funding; Tolero: Research Funding; Trovagene: Research Funding; Kaiser Permanente: Consultancy; Genentech-Roche: Research Funding; Geron: Research Funding; DeltaFly: Research Funding; Deciphera: Research Funding; Celator: Research Funding; FujiFilm: Research Funding; Ariad: Research Funding; Constellation: Research Funding; Cyclacel: Research Funding; Jazz Pharmaceuticals: Research Funding; Karyopharm: Research Funding; Kite Pharma: Research Funding; Mateon: Research Funding; MedImmune: Research Funding; Astellas Pharma: Honoraria, Research Funding; Actinium: Research Funding; Gamida: Research Funding; Bristol-Myers Squibb: Current equity holder in publicly-traded company, Research Funding; Daiichi Sankyo: Research Funding; Abbvie: Research Funding; Stemline: Speakers Bureau; Celgene: Research Funding, Speakers Bureau; Ono Pharma: Consultancy; Forma: Research Funding; Incyte: Consultancy, Research Funding, Speakers Bureau; Gilead: Speakers Bureau; Amgen: Consultancy, Current equity holder in publicly-traded company, Research Funding, Speakers Bureau; Onconova: Research Funding; Pfizer: Current equity holder in publicly-traded company, Research Funding; Regimmune: Research Funding; Samus: Research Funding; Agios: Consultancy, Research Funding, Speakers Bureau; AstraZeneca: Consultancy; Sanofi: Speakers Bureau. Bradley:AbbVie: Membership on an entity's Board of Directors or advisory committees, Speakers Bureau; Novartis: Consultancy, Speakers Bureau. Tiu:Astellas Pharma Global Development: Current Employment; Eli Lilly & Company: Current equity holder in publicly-traded company, Ended employment in the past 24 months. Hong:F. Hoffmann-La Roche: Current equity holder in publicly-traded company; Genentech, Inc.: Current Employment. Tong:AbbVie, Inc.: Current Employment, Other: may hold stock or other options. Qin:AbbVie: Current Employment, Other: may hold stock or other options. Dilley:AbbVie Inc.: Current Employment, Other: may hold stock or stock options. Perl:Leukemia & Lymphoma Society.: Other; AbbVie Inc, Astellas, Actinium, Bayer HealthCare Pharmaceuticals, Daiichi Sankyo Inc, FUJIFILM Pharmaceuticals USA Inc: Research Funding; AbbVie Inc, Actinium Pharmaceuticals Inc, Astellas, Daiichi Sankyo Inc, FORMA Therapeutics, Loxo Oncology Inc, a wholly owned subsidiary of Eli Lilly & Company, NewLink Genetics: Other; AbbVie Inc, Arog Pharmaceuticals Inc, Astellas, Daiichi Sankyo Inc: Consultancy; Astellas, AbbVie Inc, Daiichi Sankyo, Actinium, Forma, Syndax, Loxo: Consultancy, Honoraria. OffLabel Disclosure: Venetoclax is a B-cell lymphoma 2 inhibitor approved in combination with azacitidine, or decitabine, or low-dose cytarabine for the treatment of newly-diagnosed acute myeloid leukemia (AML) in adults who are age 75 years or older, or who have comorbidities that preclude use of intensive induction chemotherapy. Gilteritinib is a kinase inhibitor indicated for the treatment of adult patients who have relapsed or refractory acute myeloid leukemia (AML) with an FLT3 mutation as detected by an FDA-approved test.

Background: The extent of cardiac involvement has a major impact on clinical outcomes in patients with newly diagnosed light chain (AL) amyloidosis. Here, we present the hematologic responses, major organ deterioration progression-free survival (MOD-PFS) and event-free survival (MOD-EFS), and organ responses by cardiac stage in patients with newly diagnosed AL amyloidosis treated with cyclophosphamide, bortezomib, and dexamethasone (VCd) with or without daratumumab subcutaneous (DARA SC) in the ANDROMEDA trial (NCT03201965). Methods: Key eligibility criteria included newly diagnosed AL amyloidosis with measurable hematologic disease, ≥1 involved organ, cardiac stage I-IIIA (based on the European Modification of the Mayo staging system), eGFR ≥20 mL/min, and absence of symptomatic multiple myeloma. Patients were randomized (1:1) to receive DARA-VCd or VCd alone. All patients received bortezomib (1.3 mg/m2 SC weekly), cyclophosphamide (300 mg/m2 oral [PO] or intravenous [IV] weekly [500 mg maximum]), and dexamethasone (20-40 mg PO or IV weekly) for six 28-day cycles. DARA SC (1800 mg, co-formulated with recombinant human hyaluronidase PH20 in 15 mL) was administered by injection weekly in Cycles 1-2, every 2 weeks in Cycles 3-6, and every 4 weeks thereafter for up to 24 cycles. Disease evaluations occurred every 4 weeks (Cycles 1-6) and every 8 weeks (after Cycle 7) until major organ deterioration, hematologic progression, death, end of study, or withdrawal. The primary endpoint was overall (ie, at any time) hematologic complete response (CR) rate. Secondary endpoints included MOD-PFS, MOD-EFS, organ response rate, time to hematologic response, survival, and safety. Analyses of hematologic CR and MOD-PFS were performed on the intent-to-treat analysis set; cardiac response analyses were based on patients who were evaluable for cardiac response, defined as patients with baseline NT-ProNBP value ≥650 ng/L or baseline NYHA class 3 or 4 and received at least 1 administration of study treatment. Patients without a baseline assessment or post-baseline assessment were censored at randomization for the MOD-PFS analysis. Descriptive statistics were used to summarize overall CR rate and organ response rate. Hazard ratios and corresponding 95% confidence intervals were estimated based on Cox proportional hazard model. Results: A total of 388 patients were randomized to receive DARA-VCd (n=195) or VCd alone (n=193). Baseline characteristics were well balanced between treatment groups. The median age was 64 years and the proportions of patients with cardiac stage I, II, and III were 23%, 40%, and 37%, respectively. The median duration of treatment was 9.6 months for DARA-VCd and 5.3 months for VCd. Median follow-up was 11.4 months (range, 0.03-21.3+). Baseline characteristics were generally balanced across cardiac stages, except increasing cardiac stage was associated with older age (≥65 years), worse Eastern Cooperative Oncology Group performance status, more advanced renal failure (CrCl ≤30), and functionally worse heart failure (NYHA IIIA). Hematologic CR rates were higher in the DARA-VCd group than in the VCd group in patients with cardiac stages I, II, and III at baseline (Table). Cardiac and renal response rates at 6 months were also higher in the DARA-VCd group regardless of cardiac stage at baseline (Table). The hazard ratios (HRs) for MOD-PFS were 0.33, 0.55 and 0.66 for cardiac stages I, II and III, respectively, favoring DARA-VCd. Corresponding HRs for MOD-EFS were 0.24, 0.39, and 0.48, respectively. Rates of any grade adverse events (AEs) were similar in patients with and without cardiac involvement at baseline. Across both treatment arms, rates of serious treatment-emergent AEs were higher in patients with cardiac involvement at baseline than in those without. Conclusions: The benefit of DARA-VCd was retained over VCd alone across cardiac stages for hematologic CR, MOD-PFS, MOD-EFS, and organ responses. Disclosures Minnema: Kite, a Gilead Company: Speakers Bureau; Celgene: Other: travel support, Research Funding; Amgen: Consultancy; Servier: Consultancy. Dispenzieri:Alnylam: Research Funding; Intellia: Research Funding; Janssen: Research Funding; Pfizer: Research Funding; Takeda: Research Funding; Celgene: Research Funding. Comenzo:Unum: Consultancy; Prothena: Consultancy, Research Funding; Amgen: Consultancy; Sanofi: Consultancy; Caleum: Consultancy; Janssen: Consultancy, Research Funding; Karyopharm: Consultancy, Research Funding; Takeda: Consultancy, Research Funding. Kastritis:Janssen: Consultancy, Honoraria, Research Funding; Genesis Pharma: Consultancy, Honoraria; Takeda: Consultancy, Honoraria; Pfizer: Consultancy, Honoraria; Amgen: Consultancy, Honoraria, Research Funding. Wechalekar:Takeda: Honoraria, Other: Travel; Celgene: Honoraria; Janssen: Honoraria, Other: Advisory; Caelum: Other: Advisory. Witteles:Pfizer: Membership on an entity's Board of Directors or advisory committees; Alnylam Pharmaceuticals: Membership on an entity's Board of Directors or advisory committees. Maurer:Pfizer: Membership on an entity's Board of Directors or advisory committees, Research Funding; Alnylam: Membership on an entity's Board of Directors or advisory committees, Research Funding; Ionis: Research Funding; Eidos: Research Funding; Akcea: Research Funding. Tran:Janssen: Current Employment, Current equity holder in publicly-traded company. Qin:Janssen: Current Employment. Vasey:Janssen Research & Development: Current Employment, Current equity holder in publicly-traded company. Tromp:Janssen: Current Employment, Current equity holder in publicly-traded company. Weiss:Janssen: Current Employment, Current equity holder in publicly-traded company. Vermeulen:Janssen: Current Employment, Current equity holder in publicly-traded company. Jaccard:Janssen: Consultancy, Honoraria, Other: A.J. has served in a consulting or advisory role for Janssen and has received honoraria from, received research funding from, and had travel, accommodations, or other expenses paid for or reimbursed by Janssen., Research Funding; Celgene: Honoraria, Other: A.J. has served in a consulting or advisory role for Janssen and has received honoraria from, received research funding from, and had travel, accommodations, or other expenses paid for or reimbursed by Celgene., Research Funding.

Abstract Purpose: Pediatric high-grade glioma (pHGG) diagnosis portends poor prognosis and therapeutic monitoring remains difficult. Tumors release cell-free tumor DNA (cf-tDNA) into cerebrospinal fluid (CSF), allowing for potential detection of tumor-associated mutations by CSF sampling. We hypothesized that direct, electronic analysis of cf-tDNA with a handheld platform (Oxford Nanopore MinION) could quantify patient-specific CSF cf-tDNA variant allele fraction (VAF) with improved speed and limit of detection compared with established methods. Experimental Design: We performed ultra-short fragment (100–200 bp) PCR amplification of cf-tDNA for clinically actionable alterations in CSF and tumor samples from patients with pHGG (n = 12) alongside nontumor CSF (n = 6). PCR products underwent rapid amplicon-based sequencing by Oxford Nanopore Technology (Nanopore) with quantification of VAF. Additional comparison to next-generation sequencing (NGS) and droplet digital PCR (ddPCR) was performed. Results: Nanopore demonstrated 85% sensitivity and 100% specificity in CSF samples (n = 127 replicates) with 0.1 femtomole DNA limit of detection and 12-hour results, all of which compared favorably with NGS. Multiplexed analysis provided concurrent analysis of H3.3A (H3F3A) and H3C2 (HIST1H3B) mutations in a nonbiopsied patient and results were confirmed by ddPCR. Serial CSF cf-tDNA sequencing by Nanopore demonstrated correlation of radiological response on a clinical trial, with one patient showing dramatic multi-gene molecular response that predicted long-term clinical response. Conclusions: Nanopore sequencing of ultra-short pHGG CSF cf-tDNA fragments is feasible, efficient, and sensitive with low-input samples thus overcoming many of the barriers restricting wider use of CSF cf-tDNA diagnosis and monitoring in this patient population.

Abstract Background: Discovery of methylated DNA markers (MDM) of esophageal squamous cell carcinoma (ESCC) has sparked interest in assessing these markers in tissue. We evaluated MDMs in ESCC from three geographically and ethnically distinct populations, and explored the feasibility of assaying MDMs from DNA obtained by swallowed balloon devices. Methods: MDMs were assayed in ESCC and normal tissues obtained from the populations of United States, Iran, and China, and from exfoliative cytology specimens obtained by balloons in a Chinese population. Areas under the receiver operating curve (AUC) of MDMs discriminating ESCC from normal tissues were calculated. Random forest prediction models were built, trained on U.S. cases and controls, and calibrated to U.S.-only controls (model 1) and three-country controls (model 2). Statistical tests were used to assess the relationship between dysplasia and MDM levels in balloons. Results: Extracted DNA from 333 ESCC and 322 normal tissues was analyzed, in addition to archival DNA from 98 balloons. For ESCC, model 1 validated in Iranian and Chinese tissues with AUCs of 0.90 and 0.87, and model 2 yielded AUCs of 0.99, 0.96, and 0.94 in tissues from the United States, Iran, and China, respectively. In Chinese balloons, MDMs showed a statistically significant trend of increasing levels with increasing grades of dysplasia (P &lt; 0.004). Conclusions: MDMs accurately discriminate ESCC from normal esophagus in tissues obtained from high- and low-incidence countries. Preliminary data suggest that levels of MDMs assayed in DNA from swallowed balloon devices increase with dysplasia grade. Larger studies are needed to validate these results. Impact: MDMs coupled with minimally invasive collection methods have the potential for worldwide application in ESCC screening.

Abstract Background: PD-L1 is an immune checkpoint protein that may display intrinsic, non-immune functions in human cancer cells. Previously, we discovered that PD-L1 is regulated by BRAFV600E via YAP and c-Jun, and whose deletion can confer chemoresistance due to a decrease in the BH3-only BIM protein in colorectal cancer (CRC) cells. Here, we hypothesize that release of pro-apoptotic BIM from its sequestration by MCL-1 or BCL-2 can overcomes drug resistance mediated by depletion of PD-L1. Materials and Methods: Parental and PD-L1 knockout human (RKO) and murine (MC38) CRC cells with or without reconstituted PD-L1 were utilized. RKO cells with knockdown of MCL-1 or BCL-2 by shRNA were generated. Cells were treated with the MCL-1 selective inhibitor AZD5591 or the BCL-2/BCL-xL inhibitor ABT-263 alone or combined with the MEK inhibitor, cobimetinib. Apoptosis was measured by immunoblotting of cleaved caspase-3 and by Annexin V labeling using FACS. Clonogenic cell survival assay was performed. Protein/protein interaction was analyzed by immunoprecipitation assay. Results: BIM induction by cobimetinib was insufficient to overcome chemoresistance due to loss of PD-L1. Using a potent and selective inhibitor of MCL-1 (AZD-5591), we demonstrate that concurrent antagonism of MCL-1 and MEK can overcome apoptosis resistance in both human and murine PD-L1 knockout CRC cells. Specifically, inhibition of MCL-1 by AZD-5591 or gene knockdown combined with cobimetinib suppresses clonogenic cell survival and enhances apoptosis in cells with PD-L1 knockout, wild type or those with reconstituted PD-L1. Mechanistically, the interaction of BIM with MCL-1 is increased in PD-L1 knockout (versus wild-type cells) in the presence of cobimetinib, and enhanced binding of BIM to MCL-1 is associated with BIM phosphorylation at Thr116. Targeting MCL-1 using AZD-5591 or MCL-1 shRNA releases BIM from its sequestration by MCL-1 and results in enhanced apoptotic signaling induced by cobimetinib to an equivalent extent in wild type and PD-L1 knockout cells with or without reconstitution of PD-L1. Similarly, targeting BCL-2 by ABT-263 or by BCL-2 shRNA releases BIM from its binding to BCL-2, and enhances apoptosis induction by cobimetinib independent of PD-L1 status. Enhanced binding of BIM to BCL-2 was also associated with BIM phosphorylation at Thr116. Conclusion: Chemoresistance mediated by loss of PD-L1 can be reversed by the use of BH3 mimetic drugs combined with MEK inhibition in CRC cells to exploit their apoptotic dependency on BIM expression. Citation Format: Lei Sun, Arpad Patai, Bo Qin, Frank A. Sinicrope. Reversal of PD-L1-mediated chemoresistance by MCL-1/BCL-2 antagonism in colon cancer cells [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1821.

Abstract BackgroundThe effect of angiotensin-converting enzyme inhibitor/angiotensin receptor blockers (ACEI/ARB) on the COVID-19 remains controversial from clinic evidence. MethodsThis is a retrospective, two-center case series of 198 consecutive COVID-19 patients with a history of hypertension. ResultsAmong 198 patients, 58 (29.3%) and 16 (8.1%) were on were on ARB and ACEI, respectively. Patients who were on ARB or ACEI/ARB had a significantly lower rate of severe illness and ARDS when compared with patients treated with ACEI alone or not receiving and RAAS blocker (P＜0.05). The Kaplan-Meier survival curve showed that patients with ARB in their antihypertensive regimen had a trend towards a higher survival rate when compared with individuals without ARB (adjusted hazard ratio, 0.27; 95% CI, 0.07-1.02; P = 0.054). The Cox-regression analysis to compared ACEI vs. ARB groups showed a significantly lower mortality rate in the ARB group (adjusted hazard ratio, 0.03; 95% CI, 0.00-0.58; P = 0.02). ConclusionsUsing of ARB was associated with a reduced rate of severe illness and ARDS, indicating their potential protective impact in COVID-19.