GSK3B and lip and oral cavity carcinoma: We used two strains of cultured oral cancer cells, one with reduced EGFR expression (OECM1 cells) and one with elevated EGFR expression (SAS cells), and measured downstream effects, such as phosphorylation of β-catenin and GSK-3β, association of β-catenin with E-cadherin, and target gene regulation.