The Flavonoid Quercetin Inhibits Pancreatic Cancer Growth In Vitro and In Vivo

Objectives: The flavonoid quercetin holds promise as an antitumor agent in several preclinical animal models. However, the efficacy of oral administration of quercetin in a pancreatic cancer mouse model is unknown. Methods: The antiproliferative effects of quercetin alone or in combination with gemcitabine were tested in 2 human pancreatic cancer cell lines using cell count and MTT assays. Apoptosis was evaluated by flow cytometry. Tumor growth in vivo was investigated in an orthotopic pancreatic cancer animal model using bioluminescence. Quercetin was administered orally in the diet. Results: Quercetin inhibited the growth of pancreatic cancer cell lines, which was caused by an induction of apoptosis. In addition, dietary supplementation of quercetin attenuated the growth of orthotopically transplanted pancreatic xenografts. The combination of gemcitabine and quercetin had no additional effect compared with quercetin alone. In vivo quercetin caused significant apoptosis and reduced tumor cell proliferation. Conclusions: Our data provide evidence that oral administration of quercetin was capable of inhibiting growth of orthotopic pancreatic tumors in a nude mouse model. These data suggest a possible benefit of quercetin in patients with pancreatic cancer.