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Chi-Wan Chow
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MA06 - PDL1, TMB and DNA Repair (ID 903)
- Event: WCLC 2018
- Type: Mini Oral Abstract Session
- Track: Biology
- Presentations: 1
- Moderators:
- Coordinates: 9/24/2018, 13:30 - 15:00, Room 206 AC
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MA06.02 - Prospective Immunogenomic Profiling of Non-Small Cell Lung Cancer: Genomic and Immune Profiling Updates from Project ICON (ID 13523)
13:35 - 13:40 | Author(s): Chi-Wan Chow
- Abstract
- Presentation
Background
Our previous work has demonstrated that higher level of genomic complexity is associated with more heterogeneous neoantigen repertoire, suppressed T cell repertoire and postsurgical relapse in localized non-small cell lung cancers (NSCLC) highlighting the complex interaction of tumor molecular and immune landscape and their impact on cancer biology and patient survival. We launched the ICON Project (Immune Genomic Profiling of NSCLC) to prospectively delineate the molecular and immune landscape of early stage NSCLC and their impact on patient survival through a multidisciplinary approach. Here we report the updated genomic and immune analyses.
a9ded1e5ce5d75814730bb4caaf49419 Method
Surgical specimens from stage I-III NSCLC were subjected to whole-exome and RNA sequencing for mutational analysis, in silico neoantigen prediction and gene expression analysis as well as T cell receptor sequencing, cytometry by time-of-flight and multiplex immunofluorescence staining.
4c3880bb027f159e801041b1021e88e8 Result
From 2016-2018, 127 patients were accrued and 50 surgical samples have undergone WES, RNAseq, TCR sequencing and immune phenotyping. Median age is 66 yrs (range: 39-86), 52% (26/50) were female and 76% (38/50) former smokers. 76% (38/50) are non-squamous carcinomas and 24% (12/50) squamous cell carcinomas. 34% have stage I disease (17/50), 30% stage II (15/50), 34% stage III (17/50) and 2% stage IV (1/50). The majority of patients had upfront surgery (45/50; 90%). With median follow-up of 19 months, 15 patients have relapsed. Median tumor mutational burden is 7.8mut/Mb and predicted neoantigen burden was 10/sample (range: 0-250). Predicted neoantigen burden is significantly correlated with tumor mutational burden (r=0.41, p=0.002). The most commonly mutated genes are TP53, KRAS, CDKN2A, PIK3CA, EGFR, BRAF, GRIN2A and ATM. C->A transversions and C->T transitions were the most common mutational subtypes. PD-1 expression and regulatory T-cell (CD4+/FoxP3+) infiltration are significantly increased in tumor tissue compared to normal tissue (p=0.003 and p=0.02 respectively), while CD3, CD8, granzyme B and CD45RO are decreased in tumor tissue compared to normal lung.
8eea62084ca7e541d918e823422bd82e Conclusion
NSCLC tumors have an immunosuppressive microenvironment compared to tumor adjacent normal lung tissues. Clinical data will be adequate to conduct genomic and immune profiling comparisons across different clinical subgroups. Mutational and neoantigen profiling are consistent with previously reported studies and correlations between molecular and immune landscapes and its impact on patient survival are ongoing.
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OA03 - Advances in Lung Cancer Pathology (ID 897)
- Event: WCLC 2018
- Type: Oral Abstract Session
- Track: Pathology
- Presentations: 1
- Moderators:
- Coordinates: 9/24/2018, 10:30 - 12:00, Room 205 BD
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OA03.05 - Characterization of the Immunologic Intra-Tumor Heterogeneity in Early Stages of Non-Small Cell Lung Cancer by Multiplex Immunofluorescence (ID 13334)
11:15 - 11:25 | Author(s): Chi-Wan Chow
- Abstract
- Presentation
Background
Recurrence of non-small cell lung carcinoma (NSCLC) is associated with genetic and epigenetic intra-tumor heterogeneity (ITH). The interaction between malignant cells, stromal cells, and tumor-associated immune-cells (TAICs), such as T-cell lymphocytes (TCLs) and tumor-associated macrophages (TAMs), is important for progression of NSCLC and the characterization of the immunologic ITH might be relevant to predict recurrence in surgically treated patients at early stages of NSCLC. The aim of this study was to characterize the immunologic ITH of primary NSCLC tumors at early stages using image analysis and multiplex immunofluorescence (mIF) approaches.
a9ded1e5ce5d75814730bb4caaf49419 Method
Eight cases of stage IA and 8 cases of stage IB surgically resected NSCLC (11 adenocarcinomas, ADCs; and 5 squamous-cell carcinomas, SCCs) with a history of early recurrence were selected for this preliminary analysis. FFPE blocks were obtained and consecutive sections were stained with two panels of mIF for immune profiling, panel 1: pan-cytokeratin (AE1/AE3), PD-L1, PD-1, CD3, CD8, and CD68; panel 2: AE1/AE3, CD3, CD8, granzyme-B (GB), CD45RO, and FOXP3. Three not adjacent, intra-tumor regions (3mm2 each) per case were randomly selected after gridding the whole tumor section. A total of 41 intra-tumor regions were scanned by Vectra multispectral-microscope and analyzed using InForm-software. TAICs were quantified in epithelial and stromal compartments from each intra-tumor region. G-Cross AUC (area under the curve) was computed for specific intervals of distances between TAICs and malignant cells. Median distance between TAICs and malignant cells within each region was calculated.
4c3880bb027f159e801041b1021e88e8 Result
The median density of TCLs and TAMs were 1527 cells/mm2 and 635 cells/mm2, respectively, without significant differences between histologic subtypes. TCLs were predominantly concentered in stromal compartment (median, 2222 cells/mm2) compared with epithelial compartment (median, 332 cells/mm2). Percentage and density of TCLs and TAMs varied 4 and 8 times, respectively, between cases and regions. Non-cytotoxic T-cells and inactive cytotoxic T-cells were the most prevalent phenotypes. Higher density of TAMs and antigen-experienced TCLs were observed in stage IB than stage IA.
8eea62084ca7e541d918e823422bd82e Conclusion
Characterization of immunologic ITH of NSCLC is able by mIF and image analysis with FFPE tumor tissue. There is variability of TAICs densities between regions from the same tumor and different subpopulations were observed. TAMs and exhausted T-cells were more prominent in stage IB (tumor >3cm) suggesting these cells may play an important role in recurrence. Ongoing studies with a larger cohort and comparison with non-recurrent surgically treated patients are warranted. Supported by CPRITRP160668 and UTLungSPORE grants
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