Abstract 916: Combined focal radiation and immune checkpoint inhibition enhances anti-tumor responses over single agent treatment in a murine mammary carcinoma model

Author(s):  
Brogan Yarzabek ◽  
Philip Lapinski ◽  
David Draper ◽  
Scott Wise ◽  
Maryland Franklin
2021 ◽  
Vol 39 (15_suppl) ◽  
pp. 9049-9049
Author(s):  
Noura J. Choudhury ◽  
Jaime Laurel Schneider ◽  
Tejas Patil ◽  
Viola Weijia Zhu ◽  
Debra A. Goldman ◽  
...  

9049 Background: ROS1 fusions are oncogenic drivers in various cancers types, including 1-3% of non-small cell lung cancers (NSCLCs). Immunotherapy approvals for NSCLC include ROS1-rearranged carcinomas, but the activity of immune checkpoint inhibition (ICI) as monotherapy or in combination with chemotherapy (chemo-ICI) therapy, as well as the immunophenotypic characteristics of these tumors, have not been described in a large data set. Methods: In this multi-institutional study, patients with ROS1-rearranged NSCLC were identified retrospectively. Tumor PD-L1 expression and tumor mutational burden (TMB) were assessed as part of routine clinical care. In patients who received ICI monotherapy or chemo-ICI in the metastatic setting, time to treatment discontinuation (TTD) and objective response rate (ORR; RECIST v. 1.1) were calculated. TTD was assessed with Kaplan-Meier methods; patients remaining on treatment were censored at last follow up. Results: 184 patients with ROS1-rearranged NSCLC were identified. Among 146 PD-L1 evaluable cases, PD-L1 expression was < 1% in 60 (41%), 1-49% in 35 (24%) and ≥50% in 51 (35%) tumors. Ninety-two of 100 (92%) TMB-evaluable tumors had < 10 mutations/megabase (mut/Mb). TMB was significantly lower for ROS1-rearranged NSCLCs (n = 97) vs. ROS1-wild type tumors (n = 5,380) evaluated with next-generation sequencing using MSK-IMPACT (median 2.6 vs. 5.9 mut/Mb, p < 0.001). Twenty-eight patients received ICI monotherapy and 11 patients received chemo-ICI. The median TTD was 2.1 months (95% CI: 1.0-4.2; n = 28) for single-agent ICI therapy and 10 months (95% CI: 4.7-14.1; n = 11) for chemo-ICI therapy. The ORR was 13% (2/16 RECIST-evaluable; 95% CI: 2-38%) for ICI monotherapy and 83% (5/6 RECIST-evaluable; 95% CI: 36-100%) for chemo-ICI therapy. There was no difference in PD-L1 tumor expression (p = 0.9) or TMB (p = 0.8) between responders and non-responders and no correlation between PD-L1 tumor expression (rho = 0.16, p = 0.6) or TMB (rho = 0.03, p = 0.9) and maximum change in sum of target lesions. Conclusions: Most ROS1-rearranged NSCLCs have low or no PD-L1 expression and low TMB. The activity of checkpoint inhibitor monotherapy is disappointing in ROS1-driven NSCLC. In contrast, combination chemoimmunotherapy can achieve clinically meaningful activity.


2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii363-iii363
Author(s):  
Eric Bouffet ◽  
Sumedha Sudhaman ◽  
Jiil Chung ◽  
Jacalyn Kelly ◽  
Ailish Coblentz ◽  
...  

Abstract Pediatric brain tumors with replication repair deficiency (RRD) are hypermutant and may respond to immune checkpoint inhibition (ICI). We performed a consortium registry study of ICI in recurrent RRD cancers. Clinical and companion biomarkers were collected longitudinally on all patients. Biomarkers included tumor mutational burden (TMB), neoantigens and genetic signatures obtained from whole genome and exome sequencing. Immune inference was obtained by RNAseq and T cell rearrangement was collected in the tumor and in blood throughout treatment. Of the 46 tumors on the study, 32 were brain tumors with glioblastoma in 96%. Rapid, objective responses (&gt;50%) were observed in 50% of glioblastomas. Three year overall survival for the whole cohort was 48+/-8% which compares favorably with historical controls. Brain tumors fared worse with OS of 39+/-10% and late recurrences observed even after 2 years of therapy (p=0.02). Tumor size and acute “flare” constitute poor outcome throughout all cancers. While all tumors are hypermutant, TMB and predicted neoantigens correlated with response to ICI (p=0.02). Specific signatures extracted from SNVs and total mutations predicted response to ICI and favorable outcome (p=0.005). RNA inference and TCR reveal that the FLARE phenotype is mostly acute nonspecific immune response and not true progression. Finally, glioblastomas (n=8) which failed single agent ICI had favorable responses to combinational immunotherapies with prolonged survival of 65%+/-8% at one year after failure vs 0 for other patients (p=0.01). RRD glioblastomas exhibit favorable outcome and responses to ICI. Combinational therapies based on tumor and immune signatures of these cancers are necessary.


2020 ◽  
Author(s):  
Shivangi Lohia ◽  
Stephanie Flukes ◽  
Alexander N. Shoushtari ◽  
Akash D. Shah ◽  
Ian Ganly ◽  
...  

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Shuang Qu ◽  
Zichen Jiao ◽  
Geng Lu ◽  
Bing Yao ◽  
Ting Wang ◽  
...  

Abstract Background Although using a blockade of programmed death-ligand 1 (PD-L1) to enhance T cell immune responses shows great promise in tumor immunotherapy, the immune-checkpoint inhibition strategy is limited for patients with solid tumors. The mechanism and efficacy of such immune-checkpoint inhibition strategies in solid tumors remains unclear. Results Employing qRT-PCR, Sanger sequencing, and RNA BaseScope analysis, we show that human lung adenocarcinoma (LUAD) all produce a long non-coding RNA isoform of PD-L1 (PD-L1-lnc) by alternative splicing, regardless if the tumor is positive or negative for the protein PD-L1. Similar to PD-L1 mRNA, PD-L1-lnc in various lung adenocarcinoma cells is significantly upregulated by IFNγ. Both in vitro and in vivo studies demonstrate that PD-L1-lnc increases proliferation and invasion but decreases apoptosis of lung adenocarcinoma cells. Mechanistically, PD-L1-lnc promotes lung adenocarcinoma progression through directly binding to c-Myc and enhancing c-Myc transcriptional activity. Conclusions In summary, the PD-L1 gene can generate a long non-coding RNA through alternative splicing to promote lung adenocarcinoma progression by enhancing c-Myc activity. Our results argue in favor of investigating PD-L1-lnc depletion in combination with PD-L1 blockade in lung cancer therapy.


Sign in / Sign up

Export Citation Format

Share Document