Serum and salivary myeloperoxidase in oral squamous cell carcinoma: A preliminary study

Background: Free radical damage to biologic molecules forms a basis for cancer development. Since DNA damage and methylation states are influenced by oxidative species catalyzed by myeloperoxidase (MPO), this enzyme is postulated to have a role in the occurrence of cancer. MPO has been studied in cancers such as those of the lung, ovary, and breast. However, serum and salivary studies of MPO in oral cancer are lacking. Aims: (1) To determine the MPO levels in the serum and saliva of patients with primary oral squamous cell carcinoma (OSCC). (2) To compare and correlate the serum and salivary MPO levels in patients with primary OSCC and healthy controls. Subjects and Methods: A total of 30 subjects were involved in this study, of which study group consisted of 15 subjects and control group consisted of 15 subjects. Study group included subjects with histologically proven primary OSCC. Serum and salivary samples were collected from all the subjects. Results: The results showed that the serum levels of MPO were slightly higher in the study group as compared to the control group; however, the difference was not significant. In saliva, levels of MPO were slightly lower in the study group as compared to the control group. The difference was not significant. Conclusions: This study could not find a significant correlation between serum and salivary MPO and OSCC. However, our study consisted of a limited number of samples and as such can be considered a pilot study. Studies with larger sample size are needed to give better insight into the role of MPO in OSCC.