Decreased HDL-dependent paraoxonase and arylesterase enzyme activity may indicate a worse prognosis in multiple myeloma.

BACKGROUND Multiple myeloma (MM) is a haematological cancer characterized by clonal proliferation of plasma cells.The aim of this study was to investigate the activity of serum paraoxonase-1 (PON1) and arylesterase (ARE) in multiple myeloma with and without free light chain excretion(FLCe-MM and NFLCe-MM); as well as to investigate possible alterations in oxidative stress parameters. MATERIALS AND METHODS Total thiol (T.thl), oxidative stress index (OSI), total oxidant status (TOS) and total antioxidant status (TAS) were examined in addition to the PON1 and ARE enzyme activities in twenty one FLCe-MM and nineteen NFLCe-MM subjects. Routine parameters like lipid panel, serum total protein, albumin, creatinine, blood urea nitrogen (BUN), uric acid and hemoglobin levels were compared with the oxidative stress markers. RESULTS Serum total protein, BUN, creatinin, and uric acid levels were significantly higher (p=0.04, p=0.001, p=0.001 and p=0.0022, respectively), while hemoglobin and albumin levels were significantly lower in FLCe-MM patients (p=0.009 and p=0.04,respectively). PON1 and ARE activities were significantly lower in patients with FLCe-MM compared to those with NFLCe-MM (p=0.001 and p=0.008, respectively). CONCLUSIONS Depending on our results of prognostic markers of MM such as age, hemoglobin, albumin, and creatinine we feel confident to presume FLCe-MM as a subgroup with a worse prognosis. A decrease in PON1 and ARE activities may contribute to the prognosis and may be used as a prognostic tool in MM.