Lysine acetylation is a vital post-translational modification (PTM) of proteins, which plays an important role in cancer development. In healthy human liver tissues, multiple non-histone proteins were identified with acetylation modification, however, the role of acetylated proteins in hepatocellular carcinoma (HCC) development remains largely unknown. Here we performed a quantitative acetylome study of tumor and normal liver tissues from HCC patients. Overall, 598 lysine acetylation sites in 325 proteins were quantified, and almost 59% of their acetylation levels were significantly changed. The differentially acetylated proteins mainly consisted of non-histone proteins located in mitochondria and cytoplasm, which accounted for 42% and 24%, respectively. Bioinformatics analysis showed that differentially acetylated proteins were enriched in metabolism, oxidative stress, and signal transduction processes. In tumor tissues, 278 lysine sites in 189 proteins showed decreased acetylation levels, which occupied 98% of differentially acetylated proteins. Moreover, we collected twenty pairs of tumor and normal liver tissues from HCC male patients, and found that expression levels of SIRT1 (p = 0.002), SIRT2 (p = 0.01), and SIRT4 (p = 0.045) were significantly up-regulated in tumor tissues. Over-expression of possibly accounted for the widespread deacetylation of non-histone proteins identified in HCC tumor tissues, which could serve as promising predictors of HCC. Taken together, our work illustrates abundant differentially acetylated proteins in HCC tumor tissues, and offered insights into the role of lysine acetylation in HCC development. It provided potential biomarker and drug target candidates for clinical HCC diagnosis and treatment.

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.