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 »

You may have heard the very exciting data about patients with breast cancer who carry BRCA mutations. These mutations indicate a genetic predisposition for breast cancer.

The function of BRCA is DNA repair, very similar to the genes associated with familial colorectal cancer known as Lynch syndrome or HNPCC (hereditary nonpolyposis colon cancer) which are the DNA mismatch repair genes. Read the rest of this entry »