You may have heard the exciting data on PARP inhibitors for patients with mutations in the BRCA genes reported at ASCO 2009. Patients who carry these mutations are deficient in DNA repair which makes them very sensitive to PARP inhibitors which play a significant role in DNA repair.
Why does that matter for colon cancer? Well, the genetic predisposition HNPCC is caused by another DNA repair deficiency linked to mutations in MLH1, MSH2, MSH6, PMS1 and PMS2. The landmark sign for mismatch repair deficiency is microsatellite instability also called MSI. Read the rest of this entry »