Status of salivary lipid peroxidation in oral cancer and precancer

Abstract

Introduction:Lipid oxidation gives rise to number of secondary by-products. Malondialdehyde (MDA) is the principal and most widely studied product of polyunsaturated fatty acid peroxidation. This aldehyde is a highly toxic molecule and should be considered as more than just a marker of lipid peroxidation in oral carcinogenesis.Materials and Methods:Salivary malondiadldehyde was evaluated in 65 healthy controls (HC), 115 subjects with oral, potentially malignant disorders (PMD) and 50 subjects with oral squamous cell carcinoma (OSCC) using the Thiobarbituric-Trichloroacetitic acid (TBA-TCA) method.Results:A consistent elevation in the levels of salivary MDA was observed in HC with tobacco related habits, subjects with PMD and subjects with OSCC. The elevation in the salivary MDA was significant (P = 0.001) in the groups PMD and OSCC and group OSCC when compared to HC.Conclusion:The significant and encouraging findings of this study thus validate and reinforce that salivary malodialdehyde analysis can be used as an efficient, noninvasive tool for the early diagnosis of PMD and OSCC for planning comprehensive treatment protocol.

Endogenous Intoxication and Saliva Lipid Peroxidation in Patients with Lung Cancer

“…In the opposite direction, there is a decrease in glutathione, indicating the decreased activity of antioxidant enzymes. Similar results were obtained in studies of pre-cancerous changes in the oral cavity [19,23,25,26]. …”

“…Numerous researchers have discussed endogenous intoxication and lipid peroxidation in the blood and saliva, but the process is only described with a pileup of the end product, MDA [19,23,25,26,35]. Thus, the research of the MDA level in the context of pre-cancerous changes and squamous cell cancer of the mouth shows that the MDA concentration increases by 80% when going from the control group to pre-cancerous changes, and by 183% when going to moderately differentiated squamous cell cancer [35].…”

“…Special attention has been given to the comparison of saliva under normal conditions and that in smokers [22]. The researchers have reported changes to processes of lipid peroxidation in the saliva of patients with oral pre-cancer and cancer as exemplified by malondialdehyde [23,24,25,26]. However, the possibility of using saliva as a material to study the processes of lipid peroxidation in patients with lung cancer has not been considered so far.…”

State of lipid peroxidation and endogenous intoxication under non-small-cell lung cancer

“…[22,24,25] The changes in the lipid peroxidation processes in the saliva of patients with oral cavity precancer and cancer are described by the example of MDA. [26,27] Yet, despite the numerous literature data that show an increase in the level of MDA in saliva in case of malignant tumors, [28,29] we have noted that the character of MDA concentration change in case of lung cancer is nonlinearly connected with the tumor progression. [30] In this connection, for the complex assessment of the level of endogenous intoxication and lipid peroxidation processes, the determination of MDA is not that much informative.…”

“…[31] It should be noted that the MDA content increases in case of lung cancer, but we found no statistically significant increase in this indicator even despite the numerous confirmations of this fact in the literature. [22][23][24][25][26][27][28][29][30] During the performed studies, we have elicited the fact of an increase in the level of MM, which is an indirect evidence of excessive generation of active oxygen metabolites: Superoxide radicals and hydrogen peroxide. [36] Hydroxyl radicals are capable to damage the phosphoglyceride membrane structures of cell membranes and its organelles.…”