The lysosomal aminopeptidase tripeptidyl peptidase 1 displays increased activity in malignant pancreatic cysts.

The lysosomal aminopeptidase tripeptidyl peptidase 1 displays increased activity in malignant pancreatic cysts. Biol Chem. 2019 Jul 01;: Authors: Ivry SL, Knudsen GM, Caiazza F, Sharib JM, Jaradeh K, Ravalin M, O'Donoghue AJ, Kirkwood KS, Craik CS Abstract Incidental detection of pancreatic cysts has increased dramatically over the last decade, but risk stratification and clinical management remain a challenge. Mucinous cysts are precursor lesions to pancreatic cancer, however, the majority are indolent. Current diagnostics cannot identify mucinous cysts that harbor cancer or reliably differentiate these lesions from nonmucinous cysts, which present minimal risk of malignant progression. We previously determined that activity of two aspartyl proteases was increased in mucinous cysts. Using a global protease activity profiling technology, termed multiplex substrate profiling by mass spectrometry (MSP-MS), we now show that aminopeptidase activity is also elevated in mucinous cysts. The serine aminopeptidase, tripeptidyl peptidase 1 (TPP1), was detected by proteomic analysis of cyst fluid samples and quantitation using targeted mass spectrometry demonstrated that this protease was significantly more abundant in mucinous cysts. In a cohort of 110 cyst fluid samples, TPP1 activity was increased more than 3-fold in mucinous cysts relative to nonmucinous cysts. Moreover, TPP1 activity is primarily associated with mucinous cysts that harbor ...
Source: Biological Chemistry - Category: Chemistry Tags: Biol Chem Source Type: research