Applications of proteomics in oncology

Genomics has expanded the field of molecular oncology, and proteomics is complementing genomics in the fields of elucidation of pathophysiology, gene function, molecular diagnosis and anticancer drug discovery. This trend is reflected in the establishment of the Human Tumour Gene Index by the National Cancer Institute (NCI), which is now followed by the Tissue Proteomics Initiative. Laser capture microdissection (LCM) provides an ideal method for extraction of cells from specimens in which the exact morphologies of both the captured cells and the surrounding tissue are preserved. Proteomic technologies can be applied for the further characterisation and analysis of proteins. LCM can also be combined with the protein chip technology. Proteomic technologies have been used for the study of cancer of various organs including the liver, prostate, breast, bladder and oesophagus. Some of the anticancer strategies are directed against proteases that facilitate several steps in cancer progression. Proteomic mapping of blood vessels in normal and malignant tissues can be used to identify tissue-specific markers on the endothelium that serve as potential targets for in vivo drug delivery. Studies of global protein expression in human tumours have led to the identification of various polypeptide markers, potentially useful as diagnostic tools. Genes that encode proteins that are overexpressed in tumours are being identified. Demonstration of tissue or cell type specific expression of some nuclear matrix proteins has led to the search for tumour specific nuclear matrix proteins. There is considerable activity in the commercial sector to develop diagnostic tests, as well as to facilitate anticancer drug discovery using proteomic technologies. Continued refinement of techniques and methodologies to determine the abundance and status of proteins in vivo holds great promise for future study of normal cells and associated neoplasms.