SMAD2 and neoplasm: Similarly, no statistically significant differences between TGF-β1 signaling expression levels and radiological factors of calcification and content were found, but tumor volume was significantly correlated with the expression levels of TGF-β1, SMAD2, and β-catenin, with higher expression in larger volume (P = 0.05, P = 0.04, and P = 0.03, respectively).