Upregulation of CD39/NTPDases and P2 receptors in human pancreatic disease

Abstract

Chronic inflammation, fibrosis, atrophy, malignant transformation, and thromboembolic events are hallmarks of chronic pancreatic disease. Extracellular nucleotides have been implicated as inflammatory mediators in many pathological situations. However, there are minimal data detailing expression of ectonucleotidases and type-2 purinergic receptors (P2R) in chronic pancreatitis and pancreatic cancer. We have therefore defined tissue distribution and localization of the CD39 family of ectonucleotidases and associated P2R in human disease. Transcripts of ectonucleotidases (CD39 and CD39L1) together with P2R (P2X7, P2Y2, and P2Y6) are significantly increased in both chronic pancreatitis and pancreatic cancer. CD39 and CD39L1 are preferentially associated with the vasculature and stromal elements in pathological tissues. P2X7 mRNA upregulation was associated with chronic pancreatitis, and heightened protein expression was found to be localized to infiltrating cells. P2Y2 was markedly upregulated in biopsies of pancreatic cancer tissues and expressed by fibroblasts adjacent to tumors. High-tissue mRNA levels of CD39 significantly correlated with better long-term survival after tumor resection in patients with pancreatic cancer. Heightened expression patterns and localization patterns of CD39, P2X7, and P2Y2 infer associations with chronic inflammation and neoplasia of the pancreas. Our data suggest distinct roles for CD39 and P2-purinergic signaling in both tissue remodeling and fibrogenesis with respect to human pancreatic diseases.

The role of P2X7 receptors in tissue fibrosis: a brief review

“…They have suggested that when pancreatic inflammation occurs, the high ATP concentration is used by PSCs to induce IL-1β release, which activates and attracts other PSCs and immune cells. Kunzli et al [80] showed P2X 7 R upregulation in pancreatic tissue samples isolated from patients affected by CP with respect to control samples. Moreover, in a study to understand the impact of CD39 gene deletion using a mouse model of the disease, they noted P2X 7 R upregulation [80,81].…”

Disordered Pancreatic Inflammatory Responses and Inhibition of Fibrosis in CD39-Null Mice

“…16 The membranes were probed with either CD39 (C9F), CD39L1 (BZ3−4F), P2X7 and P2Y2 (Alomone Labs Ltd., Jerusalem, Israel), MMP-2 (Chemicon Int., Temecula, CA, USA), TGF-β1 (Santa Cruz Biotechnology Inc., Santa Cruz, CA, USA), CD45 (Chemicon), fibronectin and α-SMA (Sigma, St. Louis, MI, USA) or for control anti-glyceraldehyde-3-phosphate dehydrogenase (GAPDH; Amblion Inc., Woodward, TX, USA) primary antibodies. Appropriate secondary antibodies were used for detection, as previously described.…”

“…Appropriate secondary antibodies were used for detection, as previously described. 16 Equal gel loading was confirmed by analyses with GAPDH antibody.…”

“…16 Tissue sections for colocalization studies of CD39 and CD34 were fixed in 2% paraformaldehyde. Sections were incubated with primary antibodies (CD39, CD39L1 and CD34) at 4 °C over night.…”

“…We also noted P2X7 to be upregulated in CP and being localized to immune cells. 16 We next addressed whether purinergic signaling and in particular CD39 could impact pancreatic fibrosis. To test this hypothesis, we examined the course of pancreatic fibrosis and inflammation in CD39-null mice.…”