Tumor Tissue Oxidative Stress Changes and Na, K-ATPase Evaluation in Head and Neck Squamous Cell Carcinoma.

Changes in metabolism are mechanisms that are largely implicated in the development, progression, and metastasis of head and neck squamous cell carcinoma (HNSCC) and also in resistance to different anticancer therapies. Identification of biomarkers for differentiation between cancerous and normal epithelium, treatment design and prognosis remain a vital issue in the field of head and neck cancer. The present study analyzed the main biochemical changes that occur in HNSCC tumors by through mechanisms involving oxidative stress. The release of substances reactive to thiobarbituric acid was significantly lower in HNSCC tumor tissue as compared to healthy tissue. The assays related to the lipid profile assays showed changes in membrane biophysics of tumor cells due to an increase in total phospholipids and total cholesterol, as well as an increased activity and expression of the α1 subunit of Na, K-ATPase, which is fundamental in the process of carcinogenesis. The modulation of the antioxidant system was also affected, with a decrease in the catalytic activity of the enzymes superoxide dismutase (SOD) and glutathione peroxidase (GPx), as well as a reduction of glutathione (GSH) content and an increase in H2O2 content. A reduction in catalase (CAT) activity was observed. The data presented here are in accordance with important findings described by us in a previous study, involving the same individuals, but with a focus on the damage generated in red blood cells, resulting from tumor installation. Therefore, it was possible to conclude that the biochemical alterations found in HNSCC cells are fundamental for transformation and maintenance of the tumor cell and once it is installed, it is also capable of generating injuries in the patients' red blood cells. Our data demonstrate that this could be a promising biomarker for HNSCC.

Evaluation of the Erythrocyte Membrane in Head and Neck Cancer Patients.

Head and neck squamous cell carcinoma (HNSCC) is a heterogeneous and complex disease, both from a clinical and molecular point of view. The prolonged use of alcohol and tobacco, along with the release of tumor secretions can modulate blood cells, such as erythrocytes. Here, this study was conducted with 24 patients diagnosed with HNSCC and an equal number of healthy individuals are matched by age and gender. The levels of lipid peroxidation were measured using the individual plasma, while for lipid concentrations, identification and quantification Na, K-ATPase activity and osmotic fragility, the red blood cell concentrate were used. The release of TBARS was significantly higher in patients with HNSCC. The lipid profile assays demonstrated a rearrangement of the erythrocyte membrane due to a decrease in total phospholipids and phosphatidylethanolamine followed by an increase in total cholesterol and phosphatidylcholine. Na, K-ATPase activity also increased. Erythrocytes were more fragile in patients with HNSCC than in health individuals. Therefore, the membrane of erythrocytes were rearranged and Na, K-ATPase function altered in the HNSCC patients. Our findings suggests that the alcohol, tobacco and tumor secretion modulate in a specific manner that the erythrocytes membranes of these patients making this system a potential tool for HNSCC biomarker of tumor progression.