Cancer cells can resist treatment in profoundly frustrating ways – by sticking together and hiding from chemotherapy agents, by evolving cellular defenses against treatments, by pumping out toxins that should kill them. Cancer researchers, however, aren’t frustrated by the seemingly ingenious ways these cells evade death. Instead, researchers are spying on the evolving and resistant tumor cells, learning their tricks and trying to use those tricks to outwit cancer. This story describes two key categories of cancer resistance – intrinsic and extrinsic – and uses the stories of patients and researchers to explain reasons for hope.
