Lentivirus-mediated shRNA interference targeting STAT3 inhibits human pancreatic cancer cell invasion

Figure 2 Selection of the most effective STAT3 specific siRNA expression vector in 293T cells. A: Phase contrast and GFP expression under a fluorescent microscope was taken after 36-48 h in 293T cells, 1: 293T cells; 2: Transfection of pEGFP-N1 vector in 293T cells; 3: Transfection of pEGFP-N1-STAT3; 4: Co-transfected of pEGFP-N1-STAT3 and pGCL-GFP-siRNA vectors in 293T cells (original magnification × 200). B: STAT3 gene was cloned from the cDNA library with production of 2340 bp by PCR. C: pEGFP-N1-STAT3 was constructed after restricted enzyme cutting and connection with production of 300 bp by PCR. 1: pEGFP-N1 vector; 2: A special sequence was inserted in pEGFP-N1 vector; 3: Marker; 4-5: STAT3 gene over-expression vector pEGFP-N1-STAT3. D: Protein level of STAT3 in 293T cells was detected by western blotting. Lanes 1-6: 293T cells, STAT3 gene over-expression vector, non-silence control, LV-STAT3siRNA-1, -2, and-3 respectively. LV-STAT3siRNA-1 and LV-STAT3siRNA-2 can significantly knock down expression of STAT3 at the protein level.