Cancer has been a scourge on the human population for many years. Although numerous advances have been made in prevention, diagnosis and treatment of the disease, it still continues to torment mankind. Among the modern epidemics cancer is the second largest non-communicable disease and it has a sizeable contribution in the total number of deaths. With the increasing frequency of its occurrence it still remains elusive and largely incomprehensible. In recent years considerable progress has been made in understanding the molecular basis of the development of cancer. It is well established that an accumulation of genetic alterations is the basis for the progression of a normal cell to a cancer cell. This is enabled by the increasingly more aberrant function of genes that positively or negatively regulate different aspects of proliferation, apoptosis, genome stability, angiogenesis, invasion and metastasis.