Body site-dependent variations of microbiota in pancreatic cancer pathophysiology.

Lack of specific symptoms and reliable biomarkers, along with aggressive nature and resistance to therapies make pancreatic cancer one of the leading causes of death for cancer worldwide. The search for new diagnostic, prognostic, predictive and therapeutic tools that could improve clinical outcomes of patients has led, in recent years, to the investigation of potential roles for microbiota in the pathogenesis of this disease. The human microbiota encompasses trillions of microorganisms residing within several body tissues and organs, where they provide beneficial functions for host homeostasis and health. Derangements of the microbial ecology in different anatomic districts have been described in pancreatic cancer, as in many other diseases, both in patients and in animal models. In detail, infection from the gastric pathogen Helicobacter pylori and changes in composition and diversity of oral, intestinal and pancreatic microbiota have been found to associate with pancreatic cancer. Future research should assess how to potentially exploit such differences in microbiota composition as diagnostic, prognostic or predictive biomarkers, and as targets for therapeutic interventions, in the hope of improving the dismal prognosis of this insidious cancer.