The hallmarks of cancer
A major challenge for cancer medicine involves the remarkable variability of the disease, at all levels. The hallmarks of cancer constitute an organizing principle that may provide a rational basis for distilling this complexity so as to better understand mechanisms of the disease in its diverse manifestations. The conceptualization involves eight acquired capabilities—the hallmarks of cancer—and two generic characteristics of neoplastic disease that facilitate their acquisition during the multistage process of neoplastic development and malignant progression. The integration of these hallmark capabilities in symptomatic disease involves multiple cell types populating the tumor microenvironment, including heterogeneous populations of cancer cells, in particular cancer stem cells, and three prominent classes of stromal support cells. A premise is that the hallmarks of cancer constitute a useful heuristic tool for understating the mechanistic basis and interrelationships between different forms of human cancer, with potential applications to cancer therapy.