Body cells sequester cholesterol from the LDLC fraction of lipoproteins. LDL receptors are necessary for metabolizing circulating LDLC levels and nearly 80% of the plasma LDLC is cleared by LDL receptors.[5,7,15] High activity of LDL receptors attributes for lowering the serum cholesterol levels.[5,7,16] selleck Bicalutamide In the present study, a highly significant reduction was observed in the levels of TC in the oral cancer group as compared with the controls thus supporting the hypothesis postulated above. Several prospective and retrospective studies have shown an inverse association between blood lipid profile and different cancers.[2,4,5,7,17,18,19] Lohe et al. have observed an inverse relationship between serum lipid profile and oral cancer and oral precancer.[6] Patel et al.

have also observed an inverse relationship between lower plasma lipid profile and head and neck malignancies and oral precancerous conditions.[5,7] Furthermore, some investigators have also found a relation of low serum cholesterol with increased risk of cancer occurrence and mortality.[5,6,9,20,21,22] HDLC levels may be a useful indicator, reflecting the initial changes occurring in neoplastic conditions.[7] A drastic reduction in levels of HDLC was observed in our study, which is in accordance with previous reports[2,5,6,19,23,24] stating that low HDLC is an additional predictor of cancer and it might be a consequence of disease that is mediated by utilization of cholesterol for membrane biogenesis of the proliferating malignant cells.

[5,23] We observed significantly decreased TGL levels in cancer patients as compared with the controls, which is in agreement with the previous studies.[5,23] However, Alexopoulos et al. have found a non-significant difference in serum TGL between controls and patients,[5,18] while others have observed elevated TGL levels in cancer patients.[2,5,25] Serum LDLC and VLDLC levels did not reveal any significant difference between the two groups. Similar results for LDLC and VLDLC were observed in a study conducted by Chawda et al.[23] Histopathologically, the oral cancer group was graded as well-differentiated, moderately differentiated or poorly differentiated squamous cell carcinoma. While comparing all the lipid levels between the three different groups of oral cancer patients, there was no statistically significant difference found.

The results of our study were in accordance with the studies conducted by Lohe et al. and Chawda et al.[6,23] Lipid peroxidation is an essential Entinostat biochemical process that involves the oxidation of polyunsaturated fatty acids, the important components of cell membranes. Tobacco carcinogens generate reactive oxygen species and lipid peroxides, which result in tissue injury, thus damaging the cellular structural blocks like lipids, proteins, DNA, etc., This process affects essential constituents of cell membranes and might be involved in carcinogenesis/tumorigenesis.