Abstract 2691
Background
LAG-3, expressed on exhausted T cells, negatively regulates effector T-cell activation and may promote regulatory T-cell activity. MHC II, one of the ligands for LAG-3, is expressed by antigen-presenting cells and is heterogeneously upregulated on tumor cells in a variety of cancers. The LAG-3/MHC II interaction may activate LAG-3 and inhibit antitumor immunity. We performed digital spatial analysis to define the geographic association of LAG-3+ tumor-infiltrating lymphocytes (TILs) with individual MHC II+ and MHC II− tumor cells.
Methods
Bladder and gastric tumor samples (n = 20 each) of varying MHC II+ tumor expression (0–100%) were serially sectioned and stained by IHC for LAG-3, MHC II (human leukocyte antigen-DP, -DQ, and -DR), and Pan-cytokeratin. Slides were scanned via an Aperio AT2 scanner using a 20× objective and whole slide images were digitally aligned and analyzed via HALO software. LAG-3 engagement scores for the density of LAG-3+ TILs (LAG-3-D) and the proportion in close proximity (within 30 µm) to tumor cells (LAG-3-P) were computed for each sample using R software.
Results
MHC II was expressed by at least 1% of tumor cells in 55% of bladder and 70% of gastric samples. LAG-3-D and LAG-3-P within an individual tumor were significantly greater when associated with MHC II+ tumor cells (median [interquartile range] LAG-3-D = 6.53 [1.76, 24.9] cells/mm2; LAG-3-P = 46.7 [30.1, 70.4] % engaged) compared to MHC II− tumor cells (LAG-3-D = 0.616 [0.213, 2.38] cells/mm2 [P < 0.001]; LAG-3-P = 17.5 [6.09, 30.1] % engaged [P < 0.001]). Furthermore, we found significantly lower LAG-3/MHC II− tumor engagement by LAG-3-P in gastric compared to urothelial tumors (P < 0.001).
Conclusions
Digital spatial analysis of tumor cells and TILs in the tumor microenvironment is feasible without multiplex assays and can capture cell–cell relationships in tumors with heterogeneous MHC II staining. These data suggest preferential localization of LAG-3-expressing TILs to MHC II+ tumor cells within a proximity that may allow engagement and activation of LAG-3 and help define the importance of spatial analysis in predictive biomarker development for immunotherapy.
Clinical trial identification
Editorial acknowledgement
Editorial assistance was provided by Kathryn Woods, PhD, of Complete HealthVizion, funded by Bristol-Myers Squibb.
Legal entity responsible for the study
Bristol-Myers Squibb.
Funding
Bristol-Myers Squibb.
Disclosure
C.V. Hedvat: Shareholder / Stockholder / Stock options: Bristol-Myers Squibb; Full / Part-time employment: Bristol-Myers Squibb. G. Lee: Shareholder / Stockholder / Stock options: Bristol-Myers Squibb; Full / Part-time employment: Bristol-Myers Squibb. V. Baxi: Full / Part-time employment: Bristol-Myers Squibb. K. Dziuba: Full / Part-time employment: Bristol-Myers Squibb. D. Locke: Shareholder / Stockholder / Stock options: Bristol-Myers Squibb; Full / Part-time employment: Bristol-Myers Squibb. B. Li: Shareholder / Stockholder / Stock options: Bristol-Myers Squibb; Full / Part-time employment: Bristol-Myers Squibb. R. Edwards: Shareholder / Stockholder / Stock options: Bristol-Myers Squibb; Full / Part-time employment: Bristol-Myers Squibb.
Resources from the same session
3309 - Heat Shock Protein 90 chaperones and Protein Kinase D3 regulates androgen-independent prostate cancer development
Presenter: Attila Varga
Session: Poster Display session 1
Resources:
Abstract
3441 - The SWI/SNF driven reprograming for the AR cistrome is NSD2 dependent
Presenter: Katia Ruggero
Session: Poster Display session 1
Resources:
Abstract
1659 - IGF1R inhibition affects the survival of HT29 cancer cells by alterations of the TLR9- and autophagy signaling
Presenter: Györgyi Műzes
Session: Poster Display session 1
Resources:
Abstract
1379 - Characterization of atypical dMMR (deficient MisMatch Repair) tumors: a study from a large cohort of 4948 cases
Presenter: Marion Jaffrelot
Session: Poster Display session 1
Resources:
Abstract
1657 - Modulation of TLR9-dependent autophagy response via inhibition of c-Met signaling influences the survival of HT29 cancer cells
Presenter: Ferenc Sipos
Session: Poster Display session 1
Resources:
Abstract
3045 - Positive Feedback Activation of Notch Signal by Obesity Enhances Colorectal Tumorigenicity
Presenter: Dake Chu
Session: Poster Display session 1
Resources:
Abstract
2285 - The Pathological and Functional Roles of BRPF1 in Hepatocellular Carcinoma
Presenter: Lai Hung Carol Cheng
Session: Poster Display session 1
Resources:
Abstract
3210 - Protein tyrosine phosphatase non-receptor type 3 (PTPN3) could be a new therapeutic target for pancreatic cancer.
Presenter: Akio Yamasaki
Session: Poster Display session 1
Resources:
Abstract
3920 - A Novel bispecific BCMAxCD3 T cell engaging antibody that treat multiple myeloma (MM) with minimal cytokine serection
Presenter: Zhenyu Li
Session: Poster Display session 1
Resources:
Abstract
2182 - Evaluating the prevalence of the expression of PD-L1 in NSCLC specimens with short-duration formalin fixation using IHC 22C3 pharmDx
Presenter: Keiichi Ota
Session: Poster Display session 1
Resources:
Abstract