Kaur et al. [66] identified elevated levels in the salivary and serum samples of IL-6, IL-8, and TNF in patients diagnosed with oral leukoplakia, oral submucous fibrosis, and lichen planus, suggesting the high potential of these cytokines as biomarkers as they can be directly associated with oral precancerous lesions. This evidence concerns the gene TNF and Oral leukoplakia.