Systemic Oxidative and Protein Profile Dysregulation in Tobacco-Associated Oral Malignancy and Precancerous Conditions.

Introduction Tobacco-related oral carcinogenesis is a complex multistep process characterized by early biochemical and metabolic disturbances that occur before the appearance of clinically detectable diseases. This study aimed to assess and compare the systemic levels of glutathione (GSH), total plasma protein, and albumin among individuals with tobacco-associated oral cancer, individuals with potentially malignant oral disorders, and tobacco users without oral lesions. Materials and methods This cross-sectional study included 90 participants: 30 patients with oral cancer, 30 with potentially malignant oral disorders (oral submucous fibrosis and leukoplakia), and 30 healthy tobacco users serving as controls. Venous blood samples were collected under sterile conditions following a thorough clinical evaluation. Plasma GSH, total protein, and albumin concentrations were determined using standardized biochemical assays. Statistical analyses were then performed. Results Mean GSH levels were significantly elevated in the oral cancer group (9.23 ± 1.35 mg/dL) compared to the precancerous (4.78 ± 1.27 mg/dL) and control groups (2.67 ± 0.73 mg/dL) (p = 0.001). In contrast, total protein levels were highest among controls (7.25 ± 0.43 g/dL), followed by the precancerous group (6.78 ± 0.67 g/dL), and were lowest in patients with oral cancer (6.56 ± 0.47 g/dL) (p = 0.001). Albumin concentrations showed a similar declining trend, with significantly reduced values in the oral cancer group (3.43 ± 0.47 g/dL) compared to the precancerous (3.84 ± 0.47 g/dL) and control groups (4.00 ± 0.32 g/dL) (p = 0.001). Conclusion Alterations in systemic antioxidant status and protein profiles, particularly increased GSH and reduced albumin and total protein levels, may reflect early biochemical changes associated with malignant progression in tobacco users. Therefore, these markers may have potential utility in early risk assessment and preventive oral health interventions.