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C. Behrens



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    MA04 - HER2, P53, KRAS and Other Targets in Advanced NSCLC (ID 380)

    • Event: WCLC 2016
    • Type: Mini Oral Session
    • Track: Advanced NSCLC
    • Presentations: 1
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      MA04.07 - Impact of Major Co-Mutations on the Immune Contexture and Response of KRAS-Mutant Lung Adenocarcinoma to Immunotherapy (ID 6343)

      16:42 - 16:48  |  Author(s): C. Behrens

      • Abstract
      • Presentation
      • Slides

      Background:
      Activating mutations in the KRAS proto-oncogene define a prevalent and clinically heterogeneous molecular subset of lung adenocarcinoma (LUAC). We previously identified three major subgroups of KRAS-mutant LUAC on the basis of co-occurring genetic events in TP53 (KP), STK11/LKB1 (KL) and CDKN2A/B (KC) and reported that LKB1-deficient tumors exhibit a “cold” tumor immune microenvironment, with reduced expression of several immune checkpoint effector/mediator molecules, including PD-L1 (CD274). Here, we extend these findings and examine the clinical outcome of co-mutation defined KRAS subgroups to therapy with immune checkpoint inhibitors.

      Methods:
      We conducted a single-institution analysis of clinical and molecular data (PCR-based next generation sequencing of panels of 50, 134 or 409 genes) prospectively collected from patients enrolled into the MD Anderson Lung Cancer Moon Shot GEMINI database. KRAS-mutant LUAC were separated into KP, KL and K (wild-type for TP53 and STK11) groups. The log- rank test and Fisher’s exact test were used for comparison of progression-free survival (PFS) and objective response rate (ORR) respectively between the groups. In addition, automated IF-based enumeration of lymphocyte subsets was performed in 40 surgically resected LUAC (PROSPECT cohort) with available whole exome sequencing data.

      Results:
      Among 229 patients with KRAS-mutant LUAC who consented to the protocol we identified 35 patients with metastatic disease (17 KP, 6 KL, 12 K) that received immunotherapy with nivolumab (N=29), pembrolizumab (N=3), nivolumab/urelumab (N=1) and durvalumab/tremelimumab (N=2) and had robust clinical outcome data. There was no impact of different KRAS alleles (G12C/G12V/G12D) on PFS (P=0.6149, log-rank test) or ORR to immune checkpoint inhibitors (P=0.88, Fisher’s exact test, 2x3 contingency table). In contrast, co-mutation defined KRAS subgroups exhibited significantly different median PFS to immunotherapy (KP: 18 weeks, KL: 6 weeks, K: 16 weeks, P=0.0014, log-rank test). Objective responses were observed in 9/17 (52.9%) KP and 3/12 (25%) K tumors compared to 0/6 (0%) KL tumors (P=0.049, Fisher’s exact test, 2x3 contingency table). In the PROSPECT cohort of surgically resected LUACs with available whole exome sequencing data, somatic mutation in STK11 was associated with reduced intra-tumoral densities of CD3+ (P=0.0016), CD8+ (P=0.0125) and CD4+ (P=0.0036) lymphocytes.

      Conclusion:
      Mutations in STK11/LKB1 are associated with an inert tumor immune microenvironment and poor clinical response of KRAS-mutant LUAC to immune checkpoint blockade. The mechanism that underlies this phenotype and strategies to overcome it are under investigation. The impact of additional co-mutations on the immune profile and response of KRAS-mutant LUAC to immunotherapy is also being explored.

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    MA17 - Genetic Drivers (ID 409)

    • Event: WCLC 2016
    • Type: Mini Oral Session
    • Track: Biology/Pathology
    • Presentations: 1
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      MA17.10 - YES1 Kinase is a New Therapeutic Target in Non-small Cell Lung Cancer (ID 7159)

      15:26 - 15:32  |  Author(s): C. Behrens

      • Abstract
      • Presentation
      • Slides

      Background:
      Next-generation sequencing techniques have allowed the discovery of driver mutations in non-small cell lung cancer (NSCLC) that can be translated into advances in cancer diagnosis and treatment. However, specific oncogenic alterations are still unknown in a high proportion of NSCLC patients, that therefore cannot benefit from targeted therapies. The challenge is to identify new genetic alterations that allow the use of molecular-targeted therapies. In previous studies from our group (Aramburu et al. BMC Genomics 2015), the analysis of tumor molecular profiles from patients with NSCLC allowed us to identify the DNA copy number amplification of YES1 kinase (v-YES-1 Yamaguchi sarcoma viral oncogene homolog 1) as a prognostic marker in lung cancer. YES1 kinase is member of the Src family of non-receptor protein tyrosine kinases that are involved in the regulation of cell growth, apoptosis, cell-cell adhesion, cytoskeleton remodeling, and differentiation. The aim of this project is to evaluate if YES1 is a driver gene in NSCLC, and if targeting its activation may be a potential new therapeutic strategy.

      Methods:
      We first evaluated the prognostic role of YES1 protein expression in two independent series of 76 and 234 NSCLC patients, respectively. In both series, the multivariate analysis revealed that high YES1 expression is an independent poor prognostic factor for overall survival (CUN series HR: 3.416 [0.933-12.508]; MD Anderson series HR: 1.570 [1.032-2.391]). We next evaluated the effect of YES1 knockdown in 5 NSCLC cell lines with YES1 amplification and overexpression, and in 3 cell lines without YES1 amplification and with low protein expression. YES1 downregulation by two specific siRNAs decreased proliferation and cell survival only in those cells overexpressing YES1. Congruently, YES1 inhibition led to apoptosis only in those cells.

      Results:
      Consistent with these results, constitutive overexpression of YES1 in cells with low YES1 expression significantly enhanced cell proliferation. We next evaluated the effect of the multitarget Src kinase inhibitor dasatinib on the proliferation of NSCLC cell lines with high (8 cell lines) or low (4 cell lines) YES1 expression. Dasatinib dramatically inhibited proliferation in high YES1-expressing cell lines, whereas low YES1 cell lines were more resistant to dasatinib treatment (GI50s were four orders of magnitude higher in resistant cells).

      Conclusion:
      In conclusion, our results indicate that YES1 is a promising therapeutic target in NSCLC. Furthermore, amplification and high expression of YES1 may define a subset of patients who may potentially benefit from dasatinib treatment.

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    OA19 - Translational Research in Early Stage NSCLC (ID 402)

    • Event: WCLC 2016
    • Type: Oral Session
    • Track: Early Stage NSCLC
    • Presentations: 1
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      OA19.02 - Sex Differences Are Detected in the Profile of Tumor Associated Inflammatory Cells (TAICs) Are Lung Adenocarcinoma (ID 5451)

      11:10 - 11:20  |  Author(s): C. Behrens

      • Abstract
      • Presentation
      • Slides

      Background:
      A number of studies have characterized TAICs in lung cancer and associated their levels of infiltration with patients’ outcome. There is limited information about the correlation of TAICs infiltration with clinical and pathological features of lung cancer. We investigated the association between patterns of tumor infiltrating lymphocytes and macrophages with detailed clinical and pathological features in lung adenocarcinoma.

      Methods:
      We studied archival tumor tissue from 93 surgically resected lung adenocarcinomas, stages I to III. Density of TAICs expressing CD3, CD4, CD8, and CD68 was evaluated using immunohistochemistry (IHC) and image analysis. TAICs density was correlated with tumor’s histological characteristics and patients’ characteristics.

      Results:
      We found significant differences in the TAICs infiltrate density of lung adenocarcinomas based on patients’ characteristics. Overall: a) females showed higher levels of CD8+ (P=0.01) and CD3+ (P=0.03) cell density than males; b) smaller tumors (<3cms) showed more CD4+ (P=0.01) and CD3+ (P=0.03) cells than larger tumors; and, c) tumors with solid histology pattern showed higher levels of CD8+ (P=0.03) cells than non-solid pattern. No overall significant differences on TAICs infiltrates were detected by age, tobacco exposure by pack-years and TTF-1 IHC expression score. However when TAICs density of tumors was examined by sex we found the following: a) in larger tumor (>3cms), females demonstrated higher levels of CD8+ cells (P=0.0007) than males; b) tumors from females older than the median age (63 years) showed more CD4+ (P=0.04), CD8+ (P=0.009) and CD3+ (P=0.042) cells than males; c) tumors from females with <40 pack-years of tobacco history showed significantly higher levels of CD3+ (P=0.004) and CD68+ (P=0.004) cells than males; d) tumors from females with high levels of TTF1 expression (score >150) showed higher levels of CD8+ cells(P=0.03) than males; e) females with tumors having non-solid histology pattern showed higher CD8+ (P=0.02) and CD3+ (P=0.02) cells than males. Finally, tumors expressing low levels of TTF-1 and lower CD4+ cells correlated significantly with worse overall recurrence free survival and overall survival in both males (P<0.0001) and females (P=0.0072).

      Conclusion:
      In lung adenocarcinoma, TAICs infiltration correlates with clinical characteristics of patients and pathological features of tumors, particularly, sex, age, size and TTF-1 expression. Compared with men, lung adenocarcinomas from females showed higher levels of TAICs, particularly at older age, larger tumor size, less exposure to tobacco, and more differentiated histological patterns. (UT Lung SPORE and MD Anderson Moon Shot Program).

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    OA20 - Immunotherapy and Markers (ID 401)

    • Event: WCLC 2016
    • Type: Oral Session
    • Track: Biology/Pathology
    • Presentations: 1
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      OA20.05 - The Influence of Neoadjuvant Chemotherapy, on Immune Response Profile in Non-Small Cell Lung Carcinomas (ID 5738)

      11:35 - 11:45  |  Author(s): C. Behrens

      • Abstract
      • Presentation
      • Slides

      Background:
      The clinical efficacy observed with PD-1/PD-L1 inhibitors in non-small cell lung carcinoma (NSCLC) has prompted to characterize the immune response in lung tumors treated with chemotherapy. Our goal was to determine the characteristics of immune microenvironment of localized, surgically resected, NSCLCs from patients who received and did not receive neo-adjuvant chemotherapy. Using multiplex immunofluorescence (mIF) and image analysis, we investigated PD-1/PD-L1 expression, and quantified tumor infiltrating lymphocytes (TILs) and tumor associated macrophages (TAMs).

      Methods:
      We studied formalin-fixed and paraffin embedded (FFPE) tumor tissues from 111 stage II and III resected NSCLC, including 61 chemonaïve (adenocarcinoma, ADC=33; squamous cell carcinoma, SCC=28) and 50 chemotherapy-treated (ADC=30; SCC=20) tumors. mIF was performed using the Opal 7-color fIHC Kit™ and analyzed using the Vectra™ multispectral microscope and inForm™ Cell Analysis software (Perkin Elmer, Waltham, MA). The markers studied were grouped in two 6-antibody panels: Panel 1, AE1/AE3 pancytokeratins, PD-L1 (clone E1L3N), CD3, CD4, CD8 and CD68; and Panel 2, AE1/AE3, PD1, Granzyme B, FOXP3, CD45RO and CD57.

      Results:
      Positive PD-L1 expression (>5%) in malignant cells (MCs) was detected in 48% (n=53/111) of NSCLCs. Overall, chemotherapy-treated tumors showed significantly higher percentages of MCs expressing PD-L1 (median, 18.2%) than chemo-naïve cases (median, 1.8%; P=0.033). Higher densities of inflammatory cells expressing granzyme B (P=0.036), CD57 (P=0.001) and PD-1 (P=0.016) were detected in chemotherapy-treated NSCLCs compared with chemo-naïve tumors. In contrast, lower densities of FOXP3-positive regulatory T cells were detected in chemotherapy-treated tumors when compared with chemo-naïve cases (P=0.032). Following chemotherapy ADCs exhibited significantly higher levels of CD57-positive cells (P<0.0001) and lower density of FOXP3-positive cells (P=0.002) than chemo-naïve tumors. Chemotherapy-treated SCCs demonstrated higher density of PD-1-positive cells than chemo-naïve tumors (P=0.004). In chemotherapy-treated cancers, lower levels of CD4 helper T positive cells and tumor associated macrophages (TAMs) CD68-positive cells were associated with worse overall survival (OS; P=0.04 and P=0.005, respectively) in univariate analysis. In chemotherapy-treated ADC patients, lower levels of CD68-positive (P=0.010) and higher levels of FOXP3-positive cells correlated with worse OS (P=0.044).

      Conclusion:
      We developed a robust mIF panel of 10 markers to study inflammatory cells infiltrates in FFPE NSCLC tumor tissues. Chemotherapy-treated NSCLCs exhibited higher levels of PD-L1 expression and T cell subsets compared to chemo-naïve tumors, suggesting that chemotherapy activates specific immune response mechanisms in lung cancer. (Supported by CPRIT MIRA and UT Lung SPORE grants, and MD Anderson Moon Shot Program).

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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
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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): C. Behrens

      • 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).