MAPK3 and adenoma: Overall, the frequency of samples positive for p-ERK1/2 and PI3-K in gallbladder adenocarcinomas was significantly higher than that in surrounding tissues (χ2pERK = 10.04, P < 0.01; χ2PI3-K = 21.77, P < 0.01), in adenoma polyps (χ2pERK = 7.78, P < 0.01; χ2PI3-K = 5.06, P < 0.01), and in chronic cholecystitis (χ2pERK = 23.35, P < 0.01; χ2PI3-K = 19.67, P < 0.01).