Probiotic-derived ferrichrome inhibits the growth of refractory pancreatic cancer cells

Abstract

Pancreatic cancer is associated with a poor prognosis due to challenges in early detection, severe progression of the primary tumor, metastatic lesions, and resistance to antitumor agents. However, previous studies have indicated a relationship between the microbiome and pancreatic cancer outcomes. Our previous study demonstrated that ferrichrome derived from Lactobacillus casei, a probiotic bacteria, exhibited tumor-suppressive effects in colorectal and gastric cancer, and that the suppressive effects were stronger than conventional antitumor agents, such as 5-fluorouracil (5-FU) and cisplatin, suggesting that certain probiotics exert antitumorigenic effects. However, whether or not probiotic-derived molecules, including ferrichrome, exert a tumor-suppressive effect in other gastrointestinal tumors, such as pancreatic cancer, remains unclear. In the present study, it was demonstrated that probiotic-derived ferrichrome inhibited the growth of pancreatic cancer cells, and its tumor-suppressive effects were further revealed in 5-FU-resistant pancreatic cancer cells in vitro and in vivo in a mouse xenograft model. Ferrichrome inhibited the progression of cancer cells via dysregulation of the cell cycle by activating p53. DNA fragmentation and cleavage of poly (ADP-ribose) polymerase were induced by ferrichrome treatment, suggesting that ferrichrome induced apoptosis in pancreatic cancer cells. A transcriptome analysis revealed that the expression p53-associated mRNAs was significantly altered by ferrichrome treatment. Thus, the tumor-suppressive effects of probiotics may mediated by probiotic-derived molecules, such as ferrichrome, which may have applications as an antitumor drug, even in refractory and 5-FU-resistant pancreatic cancer.