Why cancer drugs lose their power
For 30 years, the chemotherapy drug cisplatin has been one of doctors’ first lines of defense against tumors, especially those of the lung, ovary and testes. While cisplatin is often effective when first given, it has a major drawback: Tumors can become resistant to the drug and start growing again.Now, MIT cancer biologists have shown how that resistance arises, a finding that could help researchers design new drugs that overcome cisplatin resistance. The team, led by Tyler Jacks, director of the David H. Koch Institute for Integrative Cancer Research at MIT, reports the results in the April 15 issue of the journal Genes and Development. Cisplatin and other platinum-based cancer drugs destroy tumor cells by binding to DNA strands, interfering with DNA replication. That activates the cell’s DNA repair mechanisms, but if the damage is too extensive to be repaired, the cell undergoes programmed suicide. Eventually, cancer cells learn to...