Author of

• 20182

  +

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

  • Event: WCLC 2017
  • Type: Poster Session with Presenters Present
  • Track: Chemotherapy/Targeted Therapy
  • Presentations: 1
  • Moderators:
  • Coordinates: 10/18/2017, 09:30 - 16:00, Exhibit Hall (Hall B + C)

  • 24072

    +

    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 - 09:30  |  Author(s): A. Poteete
    • 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.