The nature of cancer disease, its probable causes, and the molecular and cellular mechanisms through which malignant tumours develop, have only recently begun to be understood in any appreciable detail. Cancer is fundamentally a disease of the genome, arising from dynamic changes occurring within DNA during the lifetime of the cell e.g. deletions, amplifications, point mutations, translocations, that can occur in any cell and that may interact in a variety of cellular pathways. The imbalance in the interplay between genetic and environmental factors can initiate malignancy. The determination of the human genome sequence is acclaimed as one of the great achievements made possible by the rapid progress in the available molecular biology tools achieved during the last few years. The sequence of the human genome promises to unveil invaluable information useful for the development of novel approaches in the diagnosis and treatment of cancer disease. This book includes part of the work of international experts on the most up-to-date developments of various aspects of research on genome and proteome in oncology. The scientists suggest that the genetic key to human complexity lies not in the number of genes but in how gene parts are used to build different products in a process of the mRNA transcript called alternative splicing.