[Pancreatic cancer stem cell].

Prognosis of pancreatic cancer remains dismal due to the resistance against conventional therapies. Metastasis and massive invasion toward surrounding organs hamper radical resection. Small part of entire cancer cells reveal resistance against chemotherapy or radiotherapy, increased tumorigenicity and migratory phenotype. These cells are called as cancer stem cells, as a counter part of normal stem cells. In pancreatic cancer, several cancer stem cell markers have been identified, which enabled detailed characterization of pancreatic cancer stem cells. Recent researches clarified that conventional chemotherapy itself could increase cancer cells with stem cell-phenotype, suggesting the necessity of cancer stem cell-targeting therapy. Based on these observations, pancreatic cancer stem cell-targeting therapies have been tested, which effectively eliminated cancer stem cell fraction and attenuated cancer progression in experimental models. Clinical efficacy of these therapies need to be evaluated, and cancer stem cell-targeting therapy will contribute to improve the prognosis of pancreatic cancer.