For this reason, these chemotherapeutic agents function most effectively in active, proliferative tumors, whereas slow-growing, low-Ki-67 LI tumors, such as clear cell adenocarcinoma and mucinous adenocarcinoma, do not respond well, and treatment with these therapies may result in hyposensitivity. This evidence concerns the gene MKI67 and colon mucinous adenocarcinoma.