Fig. (3) Initiation, promotion and progression of carcinogenesis: from benign tumor to malignant tumor. (A) Survival and growth under microenvironment where no supply of energy and nutrient is available. Serum starvation in cell culture may mimic such a microenvironment in vitro. (B) Anti-apoptotic mechanism of cancer cells. Cell become invasive and enter newly formed capillary (induction of angiogenesis). (C) Newly formed capillary supports growth and survival of tumor. Cells travel through bloodstream and undergo metastasis. This scheme is adapted from “ The Bi9ology of Cancer” by R.A. Weinberg (Garland Science, 2007).