The lack of sensitization to gemcitabine by GSK-3 inhibition in pancreatic cancer might be due to number of reasons: 1) Some of the proteins targeted by GSK-3 for proteasomal degradation, including Mcl-1, β-catenin, and cdc25 [42-44], have cancer-promoting effects. The gene discussed is MCL1; the disease is familial pancreatic carcinoma.