Abstract
Background Disruptions in the pathways for activating and deactivating proteases in the bloodstream
can lead to thrombosis and bleeding issues. Leucine aminopeptidases (LAPs), which
are exopeptidases essential for regulating protein and peptide activities, are recognized
as clinical biomarkers for liver diseases. However, the relationship between serum
LAP activity and the risks of bleeding or thrombosis, as well as the identification
of the specific tissues or organs that control LAP levels, is not well understood.
Methods We performed a retrospective study to evaluate serum LAP activities in 149,360 patients
with 47 different diseases and 9,449 healthy individuals. The analysis was conducted
using SPSS V2.6, RStudio V.1.3.1073, and libraries in Python 3.8.
Results Our research revealed that 21 of the 47 diseases studied showed increased median
serum LAP activities, while 26 diseases were associated with significantly lower activities,
especially those related to thrombosis. Furthermore, most diseases were found to have
an increased risk of bleeding and thrombosis, indicated by higher Q25 and lower Q75
LAP activities compared to the control group. Receiver operating characteristic curve
analysis confirmed the effectiveness of LAP activities as biomarkers for specific
conditions like hepatic encephalopathy, liver cancer, pancreatitis, and pancreatic
cancer. Diseases were categorized into clusters with similar bleeding or thrombotic
tendencies through principal component analysis.
Conclusion This study highlighted regulatory influence of the liver and pancreas on LAP levels.
The established link between serum LAP concentrations and the risk of bleeding or
thrombosis paved the way for the development of diagnostic and preventative approaches
for various medical conditions.
Keywords
biomarkers - leucine aminopeptidase (LAP) - area under the curve (AUC) - receiving
operating characteristic (ROC) - principal component analysis
