Citations

Intra-acinar trypsinogen activation occurs in the earliest stages of pancreatitis and is believed to play important roles in pancreatitis pathogenesis. However, the exact role of intra-acinar trypsin activity in pancreatitis remains elusive. Here, we aimed to examine the specific effects of intra-acinar trypsin activity on the development of pancreatitis using a transgenic mouse model. This transgenic mouse model allowed for the conditional expression of a mutant trypsinogen that can be activated specifically inside pancreatic acinar cells. We found that expression of this active mutated trypsin had no significant effect on triggering spontaneous pancreatitis. Instead, several protective compensatory mechanisms, including SPINK1 and heat shock proteins, were upregulated. Notably, these transgenic mice developed much more severe acute pancreatitis, compared with control mice, when challenged with caerulein. Elevated tissue edema, serum amylase, inflammatory cell infiltration and acinar cell apoptosis were dramatically associated with increased trypsin activity. Furthermore, chronic pathological changes were observed in the pancreas of all transgenic mice, including inflammatory cell infiltration, parenchymal atrophy and cell loss, fibrosis, and fatty replacement. These changes were not observed in control mice treated with caerulein. The alterations in pancreata from transgenic mice mimicked the histological changes common to human chronic pancreatitis. Taken together, we provided in vivo evidence that increased intra-acinar activation of trypsinogen plays an important role in the initiation and progression of both acute and chronic pancreatitis. NEW & NOTEWORTHY Trypsinogen is activated early in pancreatitis. However, the roles of trypsin in the development of pancreatitis have not been fully addressed. Using a genetic approach, we showed trypsin activity is critical for the severity of both acute and chronic pancreatitis.

242 Background: We evaluated plasma cell free based genomic aberrations for prognosticating survival of newly diagnosed metastatic hormone sensitive prostate cancer (mHSPC) patients (pts). Methods: Plasma was collected from mHSPC pts enrolled between 2009-2014. Platelet poor plasma (PPP) fractions were processed uniformly and cell free DNA (cfDNA) extracted using Qiagen kits. Pts were followed after initiating hormonal therapy until death. Next Gen Sequencing (NGS) of cfDNA was performed using Illumina HiSeq X for a preselected panel of 128 genes (PredicineDDR-77 cancer driver genes; 29 genes in BRCA-FA homologous recombination deficiency (HRD) pathway; 22 DNA damage repair pathway genes). Statistical analyses of plasma genome based aberrations with overall survival (OS) were performed in R 3.5.1. Cox proportional-hazard models were used for survival analysis. Results: An average of 2.5 ml PPP from 99 pts yielded a median of 10.5 ng (range: 2.8-702) cfDNA per sample. 15/99 pt samples with a yield < 5 ng were excluded from sequencing; 9/99 samples failed NGS. Median follow-up time was 80.2 months (mths) (Range: 74.7, 87]); median OS was 69.1 mths (range: 54,NR). 29 pts with full NGS data had high volume metastatic disease. cfDNA yield correlated with metastatic volume (P = 0.01). Univariate analysis revealed both variables prognostic for OS (Metastatic volume: log-rank P=0.01, HR=2.1, 95% CI: 1.1-3.8; cfDNA yield: P =0.04, HR = 1.3, 95% CI: 1.03-1.7). Multivariate regression showed prognostic value of cfDNA yield remained independent of metastatic volume (P = 0.03, HR = 1.34, 95% CI: 1.02-1.76). 54/67 samples with NGS data had at least one mutation/copy number variation detected. Top mutated genes included TP53 (N=18), ATM (N=9), CHEK2 (N=7), FANCM (N=6), RB1 (N=6), BRCA2 (N=5), PIK3CA (N=4) and 37/67 pts harbored 1≥ variant in HDR pathways. These pts had a shorter survival (median: 58.6 mths) (P=0.04, HR= 2.28, 95% CI: 1.01-5.18) and pts with ATM mutations did significantly worse (median survival: 47.4 mths) (HR=4.03, P=0.0005, 95% CI: 1.73-9.37). Conclusions: Plasma cfDNA yield is prognostic for survival in newly diagnosed mHSPC state and presence of HRD pathway genomic aberrations in plasma cfDNA are associated with poor survival.

AbstractPurposeTo identify associations between implant failure and selective serotonin reuptake inhibitor (SSRI) medication use in a cohort of consecutive patients receiving dental implants during a 20‐year period.Materials and MethodsA retrospective review was conducted of all patients who received at least 1 dental implant from January 1, 1995, through December 31, 2014, assessing their history of SSRI use, active SSRI use, and SSRI use during follow‐up with implant failure. Cox proportional hazards regression models assessed associations between demographic characteristics and SSRI use with implant failure, and outcomes were summarized with hazard ratios (HRs) and 95% confidence intervals (CIs). Follow‐up SSRI use was analyzed with time‐dependent covariates.ResultsDuring the study period, 5456 patients received their first implant (median age, 53 years). The median duration of follow‐up was 5.3 years (interquartile range, 2.3‐10.2 years) for the 4927 patients who did not have implant failure. For the 529 patients who had implant failure, it occurred at a median of 0.5 years. After adjusting for age, sex, and era of implant, history of use of the SSRI sertraline was associated with an increased risk of implant failure among all patients (hazard ratio [HR], 1.60; 95% CI, 1.15‐2.23; p = 0.006) and among the subset of patients with a history of SSRI use (HR, 1.64; 95% CI, 1.07‐2.52; p = 0.02).ConclusionsIn the population reviewed, a history of sertraline use was associated with a 60% greater risk of implant failure; however, active SSRI use at the time of implant placement or during follow‐up was not significantly associated with an increased risk of implant failure.

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.

Purpose The majority of patients with cancer receive treatments that are minimally informed by omics data. We propose a precision medicine computational framework, PANOPLY (Precision Cancer Genomic Report: Single Sample Inventory), to identify and prioritize drug targets and cancer therapy regimens. Materials and Methods The PANOPLY approach integrates clinical data with germline and somatic features obtained from multiomics platforms and applies machine learning and network analysis approaches in the context of the individual patient and matched controls. The PANOPLY workflow uses the following four steps: selection of matched controls to the patient of interest; identification of patient-specific genomic events; identification of suitable drugs using the driver-gene network and random forest analyses; and provision of an integrated multiomics case report of the patient with prioritization of anticancer drugs. Results The PANOPLY workflow can be executed on a stand-alone virtual machine and is also available for download as an R package. We applied the method to an institutional breast cancer neoadjuvant chemotherapy study that collected clinical and genomic data as well as patient-derived xenografts to investigate the prioritization offered by PANOPLY. In a chemotherapy-resistant patient-derived xenograft model, we found that that the prioritized drug, olaparib, was more effective than placebo in treating the tumor ( P < .05). We also applied PANOPLY to in-house and publicly accessible multiomics tumor data sets with therapeutic response or survival data available. Conclusion PANOPLY shows promise as a means to prioritize drugs on the basis of clinical and multiomics data for an individual patient with cancer. Additional studies are needed to confirm this approach.

TPS7574 Background: The PD-1/PD-L1 pathway is an important immune checkpoint used by tumor cells to evade immune cell detection and inhibit antitumor responses. PD-1/PD-L1 expression in multiple hematologic malignancies may provide an effective target for enhancing anticancer immune response. Durvalumab (MEDI4736) is a high-affinity human IgG1 monoclonal Ab that selectively blocks PD-L1 binding to PD-1 and CD80, and has shown preliminary evidence of antitumor activity across multiple tumor types. Study objectives are to evaluate durvalumab monotherapy and combinations to determine dose and safety, as well as identify histologies and combinations that show the best complementary antitumor signals for future study. Methods: This is a phase I/II open-label, global, multicenter study of durvalumab as a monotherapy and in combination in relapsed/refractory B-cell lymphoma or CLL (MEDI4736-NHL-001; EUDRA CT 2015-003516-21; NCT02733042). Patients must have histologically-confirmed FL, MCL, splenic or nodal MZL, T-cell/histiocyte rich BCL, PMBCL, ALK+ large BCL, transformed large BCL, Richter’s transformation, DLBCL (NOS), CLL/SLL, or classical HL during the dose-finding part. Inclusion criteria are ECOG PS 0-2, and ≥1 prior antilymphoma therapy. Up to 253 patients may enroll in 4 treatment arms, which include fixed-dose durvalumab 1500 mg Q4W monotherapy or combinations with lenalidomide/rituximab, ibrutinib, or bendamustine/rituximab. The study has 3 parts: dose finding, dose confirmation, and dose expansion. The monotherapy arm does not have a dose finding or expansion part; upon progression, patients may receive combination therapy or involved-field radiation to a single nodal site (evaluating for systemic abscopal antitumor effect). Primary endpoints are safety, identification of recommended phase II dose (phase I, 3+3 design), and overall response rate (ORR; phase II); secondary endpoints include DOR, PFS, and PK/PD. ORR is measured by 2014 IWG criteria for lymphoma or modified 2008 iwCLL criteria for CLL; safety is assessed per NCI CTCAE v4.03 criteria. Recruitment is ongoing, with a target enrollment of 253 patients across 60-80 centers globally. Clinical trial information: NCT02733042.

Abstract Triple-negative breast cancer (TNBC) is characterized by elevated locoregional recurrence risk despite aggressive local therapies. New tumor-specific radiosensitizers are needed. We hypothesized that the ATR inhibitor, VX-970 (now known as M6620), would preferentially radiosensitize TNBC. Noncancerous breast epithelial and TNBC cell lines were investigated in clonogenic survival, cell cycle, and DNA damage signaling and repair assays. In addition, patient-derived xenograft (PDX) models generated prospectively as part of a neoadjuvant chemotherapy study from either baseline tumor biopsies or surgical specimens with chemoresistant residual disease were assessed for sensitivity to fractionated radiotherapy, VX-970, or the combination. To explore potential response biomarkers, exome sequencing was assessed for germline and/or somatic alterations in homologous recombination (HR) genes and other alterations associated with ATR inhibitor sensitivity. VX-970 preferentially inhibited ATR-Chk1-CDC25a signaling, abrogated the radiotherapy-induced G2–M checkpoint, delayed resolution of DNA double-strand breaks, and reduced colony formation after radiotherapy in TNBC cells relative to normal-like breast epithelial cells. In vivo, VX-970 did not exhibit significant single-agent activity at the dose administered even in the context of genomic alterations predictive of ATR inhibitor responsiveness, but significantly sensitized TNBC PDXs to radiotherapy. Exome sequencing and functional testing demonstrated that combination therapy was effective in both HR-proficient and -deficient models. PDXs established from patients with chemoresistant TNBC were also highly radiosensitized. In conclusion, VX-970 is a tumor-specific radiosensitizer for TNBC. Patients with residual TNBC after neoadjuvant chemotherapy, a subset at particularly high risk of relapse, may be ideally suited for this treatment intensification strategy. Mol Cancer Ther; 17(11); 2462–72. ©2018 AACR.