ADRB2 and lip and oral cavity carcinoma: Thereby, in light of these results we can conclude that although the present study reinforces that β2-AR is constitutive in normal oral epithelial cells and is positively correlated with the expression levels of β2-AR by OSCC cells, further clinical, cellular, and animal studies are needed to elucidate the role of β2-AR in oral cancer, specially, in relation to the importance of its decrease on tumor progression.