Abstract 720: Systematic discovery and evaluation of tumor-associated antigens (TAAs) as biomarkers in cancer immunodiagnosis

Abstract

Abstract Proteins aberrantly over-expressed in tissues from nineteen types of cancers have been identified from the Human Protein Atlas (HPA) database. Among these proteins, some were overexpressed in several types of cancers while certain proteins were found only overexpressed in certain type of cancers. It is demonstrated that aberrantly overexpressed proteins might shed into the blood and trigger the immune system to produce autoantibodies during the process of oncogenesis. Autoantibodies are more stable and often have higher titer compared to autoantigens. Therefore, we hypothesize that autoantibodies against these aberrantly overexpressed proteins may have the potential to serve as diagnostic biomarkers in certain type of cancers. In current study, we have selected 11 proteins, including EDNRB, KRT4, PLAT, MSLN, WFDC2, F5, FOXA1, AURKC, STC1, CAB39L, and SFTPA1, to further evaluate the diagnostic values of their corresponding serum autoantibodies in five types of cancers, including hepatocellular carcinoma, lung cancer, gastric cancer, breast cancer and ovarian cancer. Sera from 470 patients (94 per cancer type), 94 hepatitis patients and 192 age- and gender-matched normal controls were used in current study. Serum autoantibodies were detected by ELISA. Receiver operating curve (ROC) analysis was used to evaluate the diagnostic value of serum autoantibodies against these potential TAAs. The data indicates that several anti-TAA autoantibodies can be found to have diagnostic value for certain types of cancers. Autoantibodies against PLAT can distinguish breast and ovarian cancer while autoantibodies against SFTPA1 and CAB39L can distinguish cancers both in male and female. However, none of these serum anti-TAAs was found to be specific to a single type of cancer. In summary, HPA database has made systematic discovery of cancer biomarkers possible. Whether these in silicon biomarkers can be used to distinguish normal and cancer still needs to be evaluated in more serum samples from normal controls and cancer patients. Note: This abstract was not presented at the meeting. Citation Format: Jianxiang Shi, Lu Zhang, Peng Wang, Hua Ye, Liping Dai, Pei Li, Chenglin Luo, Chuhua Song, Kaijuan Wang, Xiao Wang, Jun Ouyang, Zhenyu Ji, Jianying Zhang. Systematic discovery and evaluation of tumor-associated antigens (TAAs) as biomarkers in cancer immunodiagnosis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 720. doi:10.1158/1538-7445.AM2017-720