SP1 and hepatocellular carcinoma: Finally, to validate our hypothesis that transcription factor SP1-mediated STK39 upregulation promotes the progression of HCC cells, we co-transfected shRNA-STK39 and pcDNA3.1-SP1 into cells to overexpress SP1, and then evaluated the effects of STK39 silencing on HCC cells proliferation, migration, invasion and EMT.