MET and neoplasm: It has been reported that tumor hypoxia microenvironment would cause abnormal activation of the oncogene MET (Stella et al. 2010), and consistent with this, the transcription level of MET was 2.54 and 1.8 times higher up-regulated in the 3D MTSs than in the 2D cultures under the control and 5-FU treatment conditions, respectively, which would promote angiogenesis and maintain tumor aggressiveness.