Abstract
Cancer is a complex family of diseases that usually begins with
carcinogenesis, in which abnormal cells divide or develop wildly by not following the
regular path of cell division and likewise can invade nearby tissues. Cancer cells
demonstrate transformations in metabolism, which is frequently more anaerobic than
normal and probably can tolerate hypoxic surroundings. The remarkable variability of
the disease, at all levels, is the major challenge for cancer medicine. Six biological
abilities gained during the multi-stage advances of human tumors are the maintenance
of proliferative signaling, the prevention of growth suppressors, cell death resistance,
replicative immortality allowance, angiogenesis induction, invasion, and metastasis
activation. In this chapter, we discuss the features of cancer cells and the epidemiology
of cancer for better understanding.