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E.R. Parra Cuentas



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    MA 05 - Immuno-Oncology: Novel Biomarker Candidates (ID 658)

    • Event: WCLC 2017
    • Type: Mini Oral
    • Track: Immunology and Immunotherapy
    • Presentations: 1
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      MA 05.02 - STK11/LKB1 Loss of Function Genomic Alterations Predict Primary Resistance to PD-1/PD-L1 Axis Blockade in KRAS-Mutant NSCLC (ID 10367)

      15:45 - 17:30  |  Author(s): E.R. Parra Cuentas

      • Abstract
      • Presentation
      • Slides

      Background:
      The genomic landscape of primary resistance to PD-1 blockade in lung adenocarcinoma (LUAD) is largely unknown. We previously reported that co-mutations in STK11/LKB1 (KL) or TP53 (KP) define subgroups of KRAS-mutant LUAD with distinct therapeutic vulnerabilities and immune profiles. Here, we present updated data on the clinical efficacy of PD-1/PD-L1 inhibitors in co-mutation defined KRAS mutant and wild-type LUAD patients and examine the relationship between genetic alterations in individual genes, tumor cell PD-L1 expression and tumor mutational burden (TMB) using cohorts form the SU2C/ACS Lung Cancer Dream Team and Foundation Medicine (FM).

      Method:
      The cohorts included 924 LUAD with NGS (FM cohort) and 188 patients with KRAS non-squamous NSCLC (SU2C cohort) who received at least one cycle of PD-1/PD-L1 inhibitor therapy and had available molecular profiling. Tumor cell PD-L1 expression was tested using E1L3N IHC (SU2C) and the VENTANA PD-L1 (SP142) assay (FM). TMB was defined as previously described and was classified as high (TMB-H), intermediate (TMB-I) or low (TMB-L).

      Result:
      188 immunotherapy-treated (83.5% nivolumab, 11.7% pembrolizumab, 4.8% anti-PD1/PD-L1 plus anti-CTLA-4) pts with KRAS-mutant NSCLC were included in the efficacy analysis. The ORR differed significantly between the KL (8.8%), KP (35.9%) and K-only sub-groups (27.3%) (P=0.0011, Fisher’s exact test). KL LUAC exhibited significantly shorter PFS (mPFS 1.8m vs 2.7m, HR=0.53, 95% CI 0.34-0.84, P<0.001, log-rank test) and OS (mOS 6.8m vs 15.6m, HR 0.53, 95% CI 0.34 to 0.84, P=0.0072, log rank test) compared to KRAS-mutant NSCLC with wild-type STK11. Loss-of function (LOF) genetic alterations in STK11 were the only significantly enriched event in PD-L1 negative, TMB-I/H compared to PD-L1 high positive (TPS≥50%), TMB-I/H tumors in the overall FMI cohort (Bonferroni adjusted P=2.38x10[-4], Fisher’s exact test) and among KRAS-mutant tumors (adjusted P=0.05, Fisher’s exact test) . Notably, PD-1 blockade demonstrated activity among 10 PD-L1-negative KP tumors, with 3 PRs and 4SDs recorded. In syngeneic isogenic murine models PD-1 blockade significantly inhibited the growth of Kras mutant tumors with wild-type LKB1 (K), but not those with LKB1 loss (KL), providing evidence that LKB1 loss can play a causative role in promoting PD-1 inhibitor resistance.

      Conclusion:
      Loss of function genomic alterations in STK11 represent a dominant driver of de novo resistance to PD-1/PD-L1 blockade in KRAS-mutant NSCLC. In addition to tumor PD-L1 status and tumor mutational burden precision immunotherapy approaches should take into consideration the STK11 status of individual tumors.

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    P2.02 - Biology/Pathology (ID 616)

    • Event: WCLC 2017
    • Type: Poster Session with Presenters Present
    • Track: Biology/Pathology
    • Presentations: 1
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      P2.02-046 - Assessment of PDL1 and Immunoprofiling Using Multiplex Quantitative Immunofluorescence in Lung Cancer: Clinical Implications (ID 10245)

      09:30 - 16:00  |  Author(s): E.R. Parra Cuentas

      • Abstract
      • Slides

      Background:
      Understanding of the “profile” of PD-L1 expression and its interplay with immune cells will provide important insights into lung cancer pathogenesis, and immunotherapeutic strategies targeting this important immune checkpoint protein. The aim was to investigate the correlation between multiplex immunofluorescence (mIF) expression of PD-L1, density and nature of tumor infiltrating immune cells in non-small cell lung carcinomas (NSCLC), and correlate those profiles with clinical and pathological variables including patient outcome.

      Method:
      We studied 194 stage II/III patients that underwent pulmonary resection, including 98 adenocarcinoma (ADC), 59 squamous cell carcinoma (SqCC), 15 large cells carcinomas (LCC) and 22 neuroendocrine carcinomas (NEC), primary tumors. Formalin-fixed and paraffin embedded (FFPE) tissue microarrays were constructed with five 1.5 mm cores representative of histologic patterns found in each tumor. mIF was performed using the Opal 7-color fIHC Kit™, scanning in the Vectra™ multispectral microscope and analyzed using the inForm™ software (Perkin Elmer, Waltham, MA). The markers studied were grouped in two 6-antibody panels: Panel 1, AE1/AE3 pancytokeratins, PD-L1 (clone E1L3N), PD-1, CD3, CD8 and CD68; and Panel 2, AE1/AE3, Granzyme B, CD45RO and CD57, FOXP3, and CD20. General linear model was used to evaluate the interaction among primary vs metastatic tumors, histologic type and TAICs and Cox's proportional hazard model for overall survival (OS).

      Result:
      Fifty-eight % out of 164 tumors were positive for PDL-1+ expression (5% cut-off) in malignant cells (EA1/EA3+). Significant higher levels of PD-L1+ expression were detected in NEC compared with other histologies (ADC, SqCC and LCC) (P=0.006). In the same way, we observed higher densities of cytotoxic T lymphocytes (CD3+CD8+) in NEC when compared with the lowest expression in SqCC (P=0.02). Large cell carcinomas presented high levels of memory/regulatory T cells (CD3+FOXP3+CD45RO+) compared with other histologic types but the difference didn´t achieve statistical significance. No difference was found for CD3+PD-L1+, CD68+PD-L1+, natural killer T lymphocytes (CD3+CD57+) and B lymphocytes (CD20+) among the histologic types. Difference between primary and metastatic tumors was found only for naive/memory T lymphocytes (CD3+ CD45RO+) (P=0.04). High CD3+FOXP3+CD45RO+ and CD3+PDL1+ expression were independent favorable prognostic factor for DFS and OS adjusted by smoking, primary vs metastatic, and histologic type [HR 2.68, 95% (CI 1.37–5.24), P=0.004; HR 2.11 (CI 1.07-4.18, P=0.03].

      Conclusion:
      High abundance of CD3+PD-L1+ cells and memory/regulatory T cells CD3+FOXP3+CD54RO are favorable prognostic factors for resected NSCLC, highlighting the importance of comprehensive assessment of both tumor and immune cells. Supported by CNPq P246042/2012-5 e CNPq 301411/2016-6; FAPESP 2013/10113-7.

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    P3.03 - Chemotherapy/Targeted Therapy (ID 719)

    • Event: WCLC 2017
    • Type: Poster Session with Presenters Present
    • Track: Chemotherapy/Targeted Therapy
    • Presentations: 1
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      P3.03-027 - LKB1 Loss Is Associated with Resistance to Anti-Angiogenic Therapy in Non-Small Cell Lung Cancer Mouse Models (ID 10259)

      09:30 - 16:00  |  Author(s): E.R. Parra Cuentas

      • Abstract

      Background:
      LKB1 is a protein kinase that is mutated and down-regulated in 20-30% of non-small cell lung cancer (NSCLC). LKB1 mutations co-occur with KRAS alterations in 7%-10% of NSCLC, resulting in an aggressive phenotype with short survival. Because LKB1 activates AMPK, the master sensor of cellular energy, many of the best known functions of LKB1 are attributed to its ability to control metabolic alterations in the cells. However LKB1 also plays an important role in regulating angiogenesis, likely as a strategy to overcome energetic depletion of tumor microenvironment. Bevacizumab, the human anti-VEGF antibody, improves the PFS and OS of NSCLC patients combined with chemotherapy, but often the benefit is transient and therapeutic resistance occurs. Our laboratory has previously identified alterations in cell metabolism and in vasculature of LKB1-deficient tumors when compared to LKB1 wild type in NSCLC.

      Method:
      LKB1 KO murine NSCLC cell lines were generated using CRISPR/Cas9 system in a KRAS[G12D] mutant background (LKR10 & LKR13). Syngeneic NSCLC models were established via s.c. injection of LKB1 intact and KO murine cells in immunocompetent mice. After tumors reached 150 mm[3] mice were randomly assigned to treatment groups consisting of vehicle, mouse anti-VEGF and nintedanib. Tumor volumes were measured and compared using student’s t test and samples were collected for vasculature analysis. Survival curves will be calculated using log rank test. Hypoxia experiments were preformed and apoptosis was measured using annexin V and 7ADD staining.

      Result:
      Treatment with anti-VEGF or nintedanib significantly inhibited tumor progression in LKB1 wt KRAS[G12D] mutant mouse model (p<0.001) but did not show any therapeutic effect in the LKB1 KO KRAS[G12D] group. Furthermore in the LKB1 wt group, the median survival of anti-VEGF and nintedanib treated mice was 111 days and 84 days respectively and 37 days in the vehicle group. No improvement in survival was detected in the LKB1 KO group after treatment with anti-VEGF. In vitro studies showed that LKB1 loss is associated with a decrease in oxygen consumption and enhanced glycolysis. Furthermore LKB1 KO NSCLC cells showed a decrease in apoptosis under hypoxic and low nutrient conditions compared to LKR13 LKB1 wt cells.

      Conclusion:
      NSCLC LKB1-deficient tumors showed resistance to anti-angiogenic therapy and this effect is driven by the regulation of metabolic adaptations that allow cells to survive under hypoxic and low nutrient conditions.