Role of free oxygen radicals and lipid peroxidation in newly diagnosed hematologic malignancies

Free oxygen radicals (FOR) play a role in ischemia, inflammation, aging and carcinogenesis. Various studies have demonstrated that SOR metabolism and lipid peroxidation were stimulated in solid tumors and hematological malignancies, differences in SOR protective enzymes may occur.In this study, the role of free oxygen radicals and protective enzymes were investigated in new diagnosed patients with suspected hematologic malignancies.According to appropriate diagnostic criteria, 51 patients (33 were male and 18 female, mean age 64 ± 15) with new diagnosed and untreated lymphoproliferative disease who were admitted to Adnan Menderes University Medical Faculty, Hematology clinic, were enrolled to this study. 21 of them were chronic lymphocytic leukemia (CLL), 18 multiple myeloma (MM) and 12 NHL. 31 healthy individuals (19 were male and 12 female, mean age 63±11) without diabetes mellitus, malignancy, acute and chronic infection, inflammatory disease were selected in this study as control group. 72%, 14%, and 14% of patients with CLL were in Stage A, Stage B and Stage C, respectively. 17%, 33%, and 50% of patients with MM were in IPI1, IPI2, and IPI3, respectively. The types of patients with NHL were diffuse large B-cell lymphoma (92%) and mantle cell lymphoma (8%). 42% of patients were at stage 1, 8% in stage 2, 8% at stage 3, and 42% at stage 4, respectively.In this study, there is no difference between patient and control groups in terms of age and sex (p>0.05). When evaluated in terms of SOD, MDA and catalase, no difference was found between control and patient groups (p>0.05). The levels of Gpx in patients with hematological malignancies were significantly lower than control group (p< 0.001). While the levels of Gpx in all patient groups were lower than control (p< 0.001 for all groups), no significant difference was determined between patient groups (p< 0.001). GSH levels in patients with hematological malignancies were higher than control group (p<0.001). While GSH levels were higher only in patients with CLL (p<0.05) and MM (p<0.005), there was no difference between patients with NHL and controls (p>0.05). However, the levels of GSH were not different in patient groups (p>0.05).In conclusion, unaffected lipid peroxidation in patients with lymphoproliferative disease may be related to decrease in Gpx and increase in GSH. This condition may be due to inhibition of lipid peroxidation by Gpx in presence of GSH and suppression of lipid peroxidation as protective mechanism of body.Key Words: Multipl myeloma, chronic lymphocytic leukemia, non-Hodgkin lymphoma, antioxidant enzymes, lipid peroxidation, glutathione