Construction of human TCRP1 gene knockout chronic myeloid leukemia K562 cell line using CRISPR/Cas9 technology and its biological function detection / 中国医师杂志

ABSTRACT

Objective:To select human chronic myeloid leukemia (CML) cell line K562 as the experimental object, and use lentivirus mediated CRISPR/Cas9 gene editing technology to construct a stable CML cell line K562/TCRP1-KO that knocks out the tongue cancer resistance related protein 1 (TCRP1) gene; and through functional tests such as cell proliferation, apoptosis, and drug sensitivity, compare the phenotypic differences between K562/TCRP1-KO and control cells (K562/cas9-CTL), and preliminarily explore the possible mechanism of TCRP1 gene involvement in the pathogenesis of CML.Methods:The small guide RNA (sgRNA) targeting TCRP1 was designed at a specific location. After annealing, the oligonucleotide fragments were recombined with the linearized Cas9 expression vector, and the lentivirus packaging system was transfected into 293T cells. The purified virus was collected and infected with K562 cells. Positive polyclons were screened for puromycin pressure, and monoclonal K562/TCRP1-KO was further screened by limited dilution method. Stable cell lines were successfully knocked out by sanger sequencing and Western blot detection; Simultaneously, K562 cells transfected with lentiCRISPR vector were constructed as control cell lines (K562/cas9-CTL); Using cell counting method, cell counting kit 8 (CCK8) method, imatinib (IM) gradient dilution method, and flow cytometry cell proliferation, drug sensitivity, and apoptosis analysis were performed on K562/TCRP1-KO and K562/cas9-CTL, respectively.Results:The sgRNA-Cas9 recombinant plasmid vector for TCRP1 knockout was successfully constructed, and after transfection into 293T cells, TCRP1 knockout monoclonal cell lines were successfully screened using limited dilution method. Compared with K562/cas9-CTL cells, the proliferation ability of K562/TCRP1-KO cells was significantly reduced, IM drug sensitivity was significantly enhanced, and the process of cell apoptosis was significantly accelerated (all P<0.05). Conclusions:A CML cell line with TCRP1 knockout was successfully constructed using CRISPR/Cas9. TCRP1 may act as a cancer related gene to affect the proliferation, IM resistance, and apoptosis process of CML cells.