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.
ABSTRACT
BACKGROUND@#Despite the progress in perinatal-neonatal medicine, complications of extremely preterm infants continue to constitute the major adverse outcomes in neonatal intensive care unit. Human umbilical cord Wharton’s Jellyderived mesenchymal stem cells (HUMSCs) may offer new hope for the treatment of intractable neonatal disorders. This study will explore the functional differences of HUMSCs between extremely preterm and term infants. @*METHODS@#UMSCs from 5 extremely preterm infants(weeks of gestation: 22+5 w,24+4 w,25+3 w,26 w,28 w) and 2 term infants(39 w,39+2 w) were isolated, and mesenchymal markers, pluripotent genes, proliferation rate were analyzed.HUVECs were injured by treated with LPS and repaired by co-cultured with HUMSCs of different gestational ages. @*RESULTS@#All HUMSCs showed fibroblast-like adherence to plastic and positively expressed surface marker of CD105,CD73 and CD90, but did not expressed CD45,CD34,CD14,CD79a and HLA-DR; HUMSCs in extremely preterm exhibited significant increase in proliferation as evidenced by CCK8, pluripotency markers OCT-4 tested by RT-PCR also showed increase. Above all, in LPS induced co-cultured inflame systerm, HUMSCs in extremely preterm were more capable to promote wound healing and tube formation in HUVEC cultures, they promoted TGFb1 expression and inhibited IL6 expression. @*CONCLUSIONS@#Our results suggest that HUMSCs from extremely preterm infants may be more suitable as candidates in cell therapy for the preterm infants.