Abstract 4371: To investigate the role of heme flux and function in growth and progression of NSCLCin vivo

Lung cancer is the leading cause of cancer-related mortality and about 85% of the cases are non-small cell lung cancer (NSCLC). Previous research from our lab has shown that the levels of rate limiting heme biosynthetic enzyme ALAS1, heme uptake proteins HCP1 and HRG1 and oxygen utilizing hemoproteins are strongly elevated in NSCLC cells. Furthermore, specific inhibition of heme synthesis using a well-known inhibitor suppresses NSCLC cell proliferation, colony formation and migration compared to normal cells. These results suggest that heme flux and function is important for NSCLC growth and progression. Lentiviral particles overexpressing eGFP, Alas1, HRG1, and HCP1 were used to transfect NSCLC cell lines. Tumorigenic properties of these cells were analyzed in vitro using invasion, migration and colony formation assay. These cell lines were used to implant subcutaneous xenografts in NOD/SCID mice (n=6). Tumor growth was monitored using Bioluminescence imaging (BLI) and Vernier caliper measurements over a period of five weeks. Mice were sacrificed, tumor tissues were harvested and processed and embedded into FFPE blocks. The tissue sections were then used for histopathological analysis (Hematoxylin and Eosin staining) and immunohistochemistry experiments. Our data show a significant increase in invasion, migration and colony formation properties of cells lines overexpressing Alas1, HRG1 and HCP1 compared to eGFP overexpressing cell lines (Control) in vitro. At week 5, BLI radiance (total photons/seconds), tumor volumes and masses of Alas1, HCP1 and HRG1 overexpression subcutaneous tumor xenografts were significantly higher compared to eGFP overexpression controls. This was further corroborated by H and E staining. Our results demonstrate that overexpression of heme synthesis and uptake proteins causes an increase in tumorigenic properties of NSCLC cells in vivo. Thus, heme flux and function plays an important role in growth and progression of NSCLC. Further studies are underway to discern the molecular mechanisms underlying the role of heme in lung tumor growth. Citation Format: Adnin Ashrafi, Poorva Ghosh, Sagar Sohoni, Li Zhang. To investigate the role of heme flux and function in growth and progression of NSCLC in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 4371.