Author of

• 17398

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  P2.01 - Poster Session with Presenters Present (ID 461)

  • Event: WCLC 2016
  • Type: Poster Presenters Present
  • Track: Biology/Pathology
  • Presentations: 1
  • Moderators:
  • Coordinates: 12/06/2016, 14:30 - 15:45, Hall B (Poster Area)

  • 17459

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    P2.01-061 - Image Analysis-Based Expression of Nine Immune Checkpoints Identifies Distinct Immunoprofiling Patterns in Non-Small Cell Lung Carcinomas (ID 5548)

    14:30 - 14:30  |  Author(s): J. Zhang
    • Abstract

    Background:
    The understanding of the co-expression of immune checkpoints in non-small cell lung carcinoma (NSCLC) is important to potentially design combinatorial immunotherapy approaches in this disease. We examined the expression of a panel of immune checkpoints markers by immunohistochemistry (IHC) and quantitative image analysis in a large cohort of surgically resected NSCLCs, and correlated those findings with patients’ clinicopathological features and tumors’ inflammatory cells infiltrate and molecular characteristics.
    
    Methods:
    We studied 225 formalin fixed and paraffin embedded (FFPE) tumor tissues from stage I-III NSCLCs, including 123 adenocarcinomas (ADC) and 83 squamous cell carcinomas (SCC), placed in tissue microarrays (TMAs). Nine immune checkpoints markers, 4 (PD-L1, B7-H3, B7-H4, IDO1) expressed predominantly in malignant cells (MCs), and 5 (ICOS, VISTA, TIM3, LAG3 and OX40) expressed mostly in stromal tumor associated inflammatory cells (TAICs). All IHC markers were examined using quantitative image analysis system (Aperio).
    
    Results:
    Using > median value of the immune checkpoint expressions as positive expression we observed that MCs H-score expressing PD-L1, B7-H3, B7-H4 and IDO1was higher in SCC than ADC, with 3 out of 4 markers showing statistically significant (P<0.05) differences. In contrast, density of TAICs expressing ICOS, VISTA, OX40, LAG3 and TIM3 was higher in ADC than SCC, with 3 out of 5 markers demonstrating significant (P<0.05) differences. Furthermore, we identified frequent co-expression of markers: a) 11% ADC (13/123) and 10% SCC (8/83) co-expressed 8 to 9 markers; b) 45% ADC (55/123) and 32% SCC (27/83) co-expressed 6 to 7 markers, c) 28% ADC (35/123) and 40% SCC (33/83) co-expressed 4 to 5 markers, and d) 16% ADC (20/123) and 18% SCC (15/83) co-expressed 2 to 3 markers. In ADC, higher number of TAICs expressing OX40 and lower levels of MCs expressing B7-H4 were detected in tumors with EGFR (median, 7.49 vs. 1.16, P=0.021) and KRAS (median, 6.88 vs. 0.67, P=0.033) mutation compared with wild-type tumors, respectively. Univariate analysis demonstrated that high B7-H4 and low OX40 expression in MCs and in TAICs respectively correlated with worse overall survival (OS; P=0.016 and P=0.037, respectively) in ADC patients.
    
    Conclusion:
    We detected different patterns of immune checkpoints expression in NSCLC with higher level of markers found in malignant cells of SCC and in stromal inflammatory cells of ADC. Immune checkpoints expression correlated with the outcome of NSCLC patients. Importantly, co-expression of several immune checkpoints is a frequent event in NSCLC (Supported by CPRIT MIRA and UT Lung SPORE grants).