[Down-regulation of human intercellular adhesion molecule-1 expression in MCF-7 cells infected by lentiviral short hairpin RNA interference vectors].

Abstract To construct lentiviral interference vectors of human intercellular adhesion molecule-1 (ICAM-1), then infect human breast cancer MCF-7 cells and identify the interference effects. Three short hairpin RNA (shRNA) interference sequences targeting human ICAM-1 gene (ICAM-1 shRNA1, ICAM-1 shRNA2 and ICAM-1 shRNA3) and a negative control sequence (NS) were designed, synthesized and cloned into the pLKO.1-SP6-PGK-GFP vector. After DNA sequencing, three plasmid-based lentiviral packaging system (vector plasmid-psPAX2-pMD2.G) was used to transfect HEK293T cells to package lentiviruses. The supernatants containing viruses were harvested to detect the viral titer. Human MCF-7 breast cancer cells were infected with the lentiviruses and the interference efficiency was detected by real-time quantitative PCR (qRT-PCR) and Western blotting. PCR showed that the designed sequences were successfully inserted into the pLKO.1-SP6-PGK-GFP vector and DNA sequencing results were correct. The qRT-PCR and Western blotting showed that the mRNA and protein expression levels of ICAM-1 in the infected MCF-7 cells decreased significantly in the ICAM-1 shRNA3 group. Lentiviral interference vectors of human ICAM-1 were constructed successfully and the expression of ICAM-1 in MCF-7 cells was down-regulated by ICAM-1 shRNA.