Ultrasound microbubble-mediated CRISPR/Cas9 knockout of C-erbB-2 in HEC-1A cells

Objective Epidermal growth factor receptor 2 (C-erbB-2) is one of the most frequently mutated oncogenes in human tumors. We aimed to evaluate the knockout efficiency of clustered regularly interspaced short palindromic repeat (CRISPR) technology using ultrasound microbubble transfection to target C-erbB-2 in human endometrial cancer (HEC)-1A cells. Methods Three single guide RNAs (sgRNAs) targeting C-erbB-2 were designed and used to construct CRISPR/CRISPR-associated (Cas)9-C-erbB-2 plasmids. The constructed plasmids were transfected into HEC-1A cells using ultrasound microbubbles. C-erbB-2 knockout cloned cells were identified by green fluorescence. C-erbB-2 mRNA and protein expression was measured by reverse transcription (RT)-PCR and western blotting, respectively. Results RT-PCR showed that C-erbB-2 mRNA expression was significantly lower in sgRNA1-transfected cells (0.57 +/- 0.06) than in blank (1.00 +/- 0.09) and negative-control groups (1.02 +/- 0.12). Western blotting revealed C-erbB-2 protein expression to be significantly lower in sgRNA1-transfected cells (0.269 +/- 0.033) than in blank (0.495 +/- 0.059) and negative-control groups (1.243 +/- 0.281). However, there was no significant difference in C-erbB-2 protein and mRNA expression in sgRNA2- and sgRNA3-transfected cells compared with controls. Conclusion Ultrasound microbubbles can mediate plasmid transfer into HEC-1A cells to interfere with gene expression and knockout C-erbB-2.