Download Understanding Cancer: The Ten Hallmarks of Cancer Cells and more Slides Biology in PDF only on Docsity! 1 PIP Digest UNDERSTANDING CANCER: Hallmarks of Cancer This PIP Digest describes the ten “hallmarks of cancer” — the crucial features and functions that distinguish cancer cells from the body’s normal cells. Key concepts • Distinct biology of cancer Related PIP Digests • Understanding Cancer: What is Cancer and Types of Cancer • Understanding Cancer: Genetics 101 • Understanding Cancer: Tumour Heterogeneity In 2000, cancer researchers Douglas Hanahan (https://en.wikipedia.org/wiki/Douglas_Hanahan) and Robert Weinberg (https://en.wikipedia.org/wiki/Robert_Weinberg) published a review article in the journal Cell, which identified six “hallmarks” or rules of how cancers behave. Their huge undertaking synthesized much of what was known at the time about the distinct biology of cancer. In an update in the same journal in 2011, the authors added four more hallmarks. These ten hallmarks (see diagram on the next page) are key to understanding and advancing cancer research. Hallmarks refer to acquired functional capabilities or properties of cancer. They activate tumours to do things normal cells do not do, to behave chronically, and to disrupt the normally well-regulated activities of the body’s cells and organs. Therapies have been developed to target each hallmark and its enablers. Often, these therapies yield dramatic results, but only for short periods. Cancer cells are very adaptable, and variants quickly emerge that resist the therapy. Attacking all hallmarks simultaneously would stop tumours in their tracks, but such an approach would likely be too toxic to be useful. Strategically combining therapies to target limited combinations of hallmarks, though, can reduce a tumour’s ability to adapt and resist. 2 PIP Digest Source: Hanahan D & Weinberg RA. (2011). Hallmarks of cancer: the next generation. Cell, 144(5):646-74. The ten major hallmarks fall into groups: those that occur inside the cell, those “enabling characteristics” that allow cancers to grow, and those that operate outside in the tumour microenvironment (outside the tumour itself). Inside the Cell 1. Sustaining proliferative signaling Normal cells have a controlled and time-limited cycle of cell division, growth, and death. In healthy tissue, certain signaling proteins called “growth factors” regulate cell proliferation. Growth factors work by binding to receptor proteins located on the surface of the plasma membrane that forms the outer boundary of all cells. Different cell types have different plasma membrane receptors and thus respond to different growth factors. When a growth factor binds to its receptor, it triggers a multi-step process — proteins relay signals that trigger molecular changes that stimulate cell growth and division. In normal cells, this growth is well regulated.
