ABSTRACT
Introduction Human carcinogenesis is a multi-step process that reflects genetic alterations, driving the progressive transformation of normal to malignant cells. The process can be arbitrarily divided into tumor initiation, tumor promotion, malignant conversion, and tumor progression. The initiation and progression to malignancy is based on the accumulation of defects or mutations in certain genes coding for certain factors. Important factors in malignant transformation are the acquired capability of:
It is thought that cancer cells must acquire these capabilities, although the means of acquisition may vary mechanistically and chronologically. In addition, escape from the immune system is necessary for malignant transformation.
