Many studies have demonstrated that cancer sera contain antibodies against a unique group of autologous cellular antigens called tumor-associated antigens (TAAs). Autoantibodies to TAAs can be used as serological markers for early diagnosis of cancer. Cancer has long been recognized as a multi-step process which involves not only genetic changes conferring growth advantage but also factors which disrupt regulation of growth and differentiation as well as lead to altered ex
Identification of TAAs
The establishment of panels of TAAs that elicit a humoral response can contribute highly to the development of methods in early screening and diagnosis of cancer. Several approaches are currently available for the identification of TAAs in cancer. One of the approaches is by using serum antibodies from cancer patients to immunoscreen cDNA ex
Over the past decade, proteomic techniques have been established in the field of cancer research to study basic and clinical aspects of cancer research. These new technologies are also being applied to facilitate the identification of novel diagnostic markers for cancer. In particular, there has been a remarkable advance in the field of proteomics over the last few years. Proteomics has the potential to discover and further expand the genetic information generated by genomics in liver cancer for several reasons. Compared to the first approach, which we have previously used, the proteome-based methodology allows individual screening of a large number of sera, as well as determination of a large number of autoantigens. The proteome-based approach can also distinguish isoforms and the detection of autoantibodies directed against post-translational modifications (PTMs) of specific targets. It is well known that mRNA levels do not necessarily correlate with corresponding protein abundance. Additional complexity of protein is conferred by PTMs including phosphorylation, acetylation, and glycosylation, as well as protein cleavage. These modifications may not reflect any change at the mRNA level but play important roles in protein stability, activity and functions. Intracellular proteins may also participate in the transformation of a healthy cell into a neoplastic cell. Therefore, protein levels may be more accessible and relevant to therapeutic targets than mRNA levels.