SP1 and gastric cancer: The luciferase activity in pGL4.10‐TNPO2 promoter (Mu) and pcDNA4.1‐SP1 cotransfection groups was not significantly higher when compared to normal control cells (Figure 2G).These observations demonstrated that DYNC1I1 decreased TNPO2 expression by downregulating SP1 expression in gastric cancer cells, further confirming that SP1 serves as a transcription factor of TNPO2.