Abstract 5144: Using proteomic approach to identify potential tumor-associated antigens (TAAs) as biomarkers in Hispanic hepatocellular carcinoma

Abstract

Abstract Hepatocellular carcinoma (HCC) is one of the most common malignancies worldwide with high prevalence and poor prognosis. The incidence rate and mortality rate in Hispanic HCC is relative higher than other ethnic groups. Autoantibodies against tumor associated antigens (TAAs) have long been proved as useful biomarkers in cancer diagnosis. In the present study, sera from 25 Hispanic patients with HCC and 25 sera from normal individuals were used in a proteomic approach to identify HCC-related TAAs. Twenty-four immunoreactive protein spots (16 from HepG2 cells, and 8 from SUN449 cells) were excised from the two-dimensional electrophoresis (2DE) gels, digested with trypsin, and subsequently analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Of 24 immunoreactive protein spots, 21 were identified with compatible molecular weights and isoelectric points. After further analysis, a total of 9 proteins were found to be potential TAAs, including endoplasmic reticulum chaperone BiP (HSPA5), 60 kDa heat shock protein (HSP60), triosephosphate isomerase (TPI1), protein disulfide-isomerase (PDI), Actin-cytoplasmic 2 (ACTG1), calreticulin (CRP55), alpha-enolase (ENO1), heat shock 70 kDa protein (HSP70), tropomyosin alpha-3 chain (TPM3). Among these proteins, HSPA5 was corresponded to 5 protein spots on the 2DE gels, while 4 proteins (HSPA5, HSP60, TPI1 and PDI) were found in both HepG2 and SNU449 cell lines. Enrichment analysis show that these proteins are mostly responsible for protein folding in endoplasmic reticulum as well as ubiquitin ligase binding function. In the subsequent study, autoantibodies against these proteins will be detected by immunoassay, and further evaluated as biomarkers in detection of Hispanic HCC. Citation Format: Yangcheng Ma, Cuipeng Qiu, Xiaojun Zhang, Xiao Wang, Jianying Zhang. Using proteomic approach to identify potential tumor-associated antigens (TAAs) as biomarkers in Hispanic hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5144.