Clinical significance of activin A and myostatin in patients with pancreatic adenocarcinoma and progressive weight loss.

Pancreatic ductal adenocarcinoma (PDAC) is characterized by progressive weight loss and nutritional deterioration. Several cytokines, such as activin A and myostatin, ligands of the transforming growth factor-β superfamily, have been shown to influence the pathogenesis of muscle wasting and tumor progression. The aim of our study was to assess the clinical significance of these cytokines in patients with different stages of PDAC. The study included 93 patients: 73 with newly diagnosed PDAC and 20 healthy volunteers as the control group. PDAC patients included 42 diagnosed with non-metastatic pancreatic cancer (stage I - III) and 31 patients with metastatic cancer (stage IV). The peripheral venous blood samples were collected from each patients at the time of cancer diagnosis and plasma concentrations of activin A and myostatin have been measured with an enzyme-linked immunoassay. Forty five patients (61.6%) presented weight loss > 5%, including 24 (57.1%) with stage I - II and 21 (67.7%) with metastatic PDAC (P > 0.05). Plasma levels of activing A were significantly higher in metastatic PDAC patients compared with stage I - III PDAC patients and control group (P < 0.01). The relationship between higher activin A levels and weight loss was also observed (P < 0.05). On the other hand, myostatin was not associated with weight loss in analysed group of patients. In conclusion, the current study demonstrates that high activin A plasma levels at the time of PDAC diagnosis is associated with unintentional weight loss and may be an useful biomarker for identifying patients with metastatic disease. However, further prospective studies are needed to fully explore the clinical significance of myostatin in pathogenesis of progressive weight loss in PDAC patients.