Why aren't cancer drugs better? The targets might be wrong

Drugs can stop cancer cells if they attack the right proteins. But a new study suggests many of these targets were chosen with dated, imprecise technology, writes Carl Zimmer

Twenty years ago, the fight against cancer seemed as if it were about to take a dramatic turn. Traditionally, cancer doctors fought the disease with crude weapons, often simply poisoning fast-growing cells whether they were cancerous or healthy. But then a team of researchers hit on a new strategy: drugs targeting proteins produced by cancer cells that seemed necessary to their survival.
 
Once such drug, Gleevec, worked spectacularly in patients with chronic myeloid leukemia. But the clinical trials that followed mostly have produced disappointments. According to a study published earlier this year, only three per cent of cancer drugs