BCAT1 Promotes Lung Adenocarcinoma Progression Through Enhanced Mitochondrial Respiration and NF-κB Pathway Activation

Abstract BCAT1 is up-regulated and acts as an oncogenic factor in many types of cancers, but its role in lung adenocarcinoma (LUAD) development is not clearly understood. Here we found BCAT1 protein level was up-regulated in tumor tissues, which was positively associated with TNM stage and local lymph node metastasis of LUAD patients. BCAT1 knockdown inhibited cell growth and mobility while BCAT1 overexpression promoted LUAD development both in vitro and in vivo. BCAAs metabolism and mitochondrial respiration were enhanced in BCAT1 overexpression cells, which were more sensitive to Leucine and Isoleucine supplements, compared to control cells. Moreover, RNA sequencing analysis suggested that differentially expressed genes (DEGs) in BCAT1 overexpression LUAD cells were enriched in metabolism, signal transduction, and immune response processes, and BCAT1 overexpression decreased NFKBIB mRNA level that induced NF-κB pathway activation in LUAD cells. As an inhibitor of NF-κB pathway, ammonium pyrrolidinedithiocarbamate (PDTC) treatment predominately counteracted the effect of NF-κB pathway activation and inhibited LUAD cells proliferation and migration, especially cells with BCAT1 overexpression. Taken together, our findings point a key role for BCAT1 in promoting LUAD development through metabolic reprogramming and NF-κB pathway activation, which provides promising molecular biomarker and therapeutic targets for LUAD diagnosis and treatment.