Analysis of 3-nitrotyrosine levels in lung cancer patients

The kinds of reactive oxygen and nitrogen which is composed as endogen and exogen can attack to lipids in cell, proteins and DNA; and harmful results can happen. According to researchs, the reactive oxygens and nitrogens have a role on the pathogenesis of the lung cancer. The nitric oxide (NO) which consists from L-Arginine is a resultant that its half-life is too short and it forms peroxynitrite by reacting with superoxide radical. Peroxynitrite composes the 3-nitrotyrosine (3-NT) by adding the nitro group to the proteins in the cell or to the independent thyrosine phenol. Lysosomal is an enzyme and catalyzer of the myeloperoxidase (MPO) which is defence enzyme against pathogens; also catalyzer of the thyrosine nitration.In our study, we aimed to analyse the changes of the MPO, 3-NT and total NO level on the patients with lung cancer. We observed 30 lung cancer patients and 25 healthy controls and found with the measurement that MPO enzyme level increases on the ill people than healthy people (p<0.005). In addition to this, we did not observe any differences on the level of total NO and 3-NT. In our study, we also investigated the effects of several factors, such as lung cancer types, gender, age, cigaratte smoking, body mass index on the parameters. Although, patients who smoke has higher MPO, 3-NT and total NO than the nonsmokers or ex-smokers; we found an important difference about the level of MPO between smokers and ex-smokers (p<0.05). When we analysed the correlations between measured parameters, it was found that there is a positive correlation between MPO and 3-NT on the only patients with adenocarcinoma (R=0.682, p<0.05).In our study, the high level of the MPO can be accepted as an evidence of the increased inflammation in the lung cancer. Furthermore, similar nitrotyrosıne level between patients and healthy controls groups can be the result of the resistance of the proteins against oxidative stress, as compared with the other biomolecules.