Background Runt-related transcription factor 1 （Runxl） plays a crucial role in hematogenesis and its dysfunction may contribute to leukemogenesis. However, it is not clear whether or not abnormal expression of Runxl...Background Runt-related transcription factor 1 （Runxl） plays a crucial role in hematogenesis and its dysfunction may contribute to leukemogenesis. However, it is not clear whether or not abnormal expression of Runxl will induce leukemia and how the change of Runxl expression level could affect BCR-ABL-induced leukemogenesis. In the present study, we aimed to analyze if abnormal expression of Runxl in BaF3 cells alone would induce teukemogenesis. And we also wanted to know if abnormal expression of Runxl in leukemic cells would affect leukemogenesis. Furthermore, we investigated whether overexpression or knock-down of Runxl in BaF3 cells would induce leukemogenesis. Methods Plasmids containing full-length Runxl cDNA were transduced into BaF3 cells and BaF3-P185wt cells （BCR-ABL transformed BaF3 cells） by electroporation. Plasmids containing a short hairpin RNA of Runxl were transduced into BaF3 cells and BaF3-P185wt cells by electroporation. Runxl expression level was quantified by Western blotting and quantitative real-time PCR. The effects of overexpression or knock-down of Runxl on proliferation, apoptosis and migration of cells were detected in vitro. Then, using MSCV-P185wt-EGFP as a control, we transplanted MSCV-P185wt-Runx1 cells or MSCV-P185wt-shRNA cells into Balb/c mice through tail vein and observed tumorgenesis of the different phenotypes. Results In vitro analysis revealed that overexpression of Runxl in P185wt cells could inhibit cell proliferation and slow down cell migration; while knock-down of Runxl could promote cell proliferation and speed up cell migration. In vivo analysis indicated that mice transplanted with MSCV-P185wt-Runx1 survived longer than controls. In contrast, mice transplanted with MSCV-P185wt-shRNA survived shorter than the control group. Gross pathological analysis revealed that the MSCV-P185wt-Runx1 group had less severe splenomegaly and hepatomegaly compared to the control group, and the MSCV-P185wt-shRNA group had more severe splenomegaly and hepatomegaly. No splenomegaly or hepatomegaly was detected in mice transplanted with MSCV-BaF3-Runxl cells or MSCV-BaF3-shRNA cells. Both the mice of MSCV-BaF3-Runxl group and MSCV-BaF3-shRNA group were healthy with no sign of leukemia for up to three months. Conclusions Overexpression or knock-down of Runxl gene in BaF3 cells alone could not induce leukemogenesis. However, in BaF3-P185wt cells, alteration of Runxl expression could affect BCR-ABL-induced proliferation and migration in vitro and leukemoaenesis in vivo.展开更多
文摘Background Runt-related transcription factor 1 （Runxl） plays a crucial role in hematogenesis and its dysfunction may contribute to leukemogenesis. However, it is not clear whether or not abnormal expression of Runxl will induce leukemia and how the change of Runxl expression level could affect BCR-ABL-induced leukemogenesis. In the present study, we aimed to analyze if abnormal expression of Runxl in BaF3 cells alone would induce teukemogenesis. And we also wanted to know if abnormal expression of Runxl in leukemic cells would affect leukemogenesis. Furthermore, we investigated whether overexpression or knock-down of Runxl in BaF3 cells would induce leukemogenesis. Methods Plasmids containing full-length Runxl cDNA were transduced into BaF3 cells and BaF3-P185wt cells （BCR-ABL transformed BaF3 cells） by electroporation. Plasmids containing a short hairpin RNA of Runxl were transduced into BaF3 cells and BaF3-P185wt cells by electroporation. Runxl expression level was quantified by Western blotting and quantitative real-time PCR. The effects of overexpression or knock-down of Runxl on proliferation, apoptosis and migration of cells were detected in vitro. Then, using MSCV-P185wt-EGFP as a control, we transplanted MSCV-P185wt-Runx1 cells or MSCV-P185wt-shRNA cells into Balb/c mice through tail vein and observed tumorgenesis of the different phenotypes. Results In vitro analysis revealed that overexpression of Runxl in P185wt cells could inhibit cell proliferation and slow down cell migration; while knock-down of Runxl could promote cell proliferation and speed up cell migration. In vivo analysis indicated that mice transplanted with MSCV-P185wt-Runx1 survived longer than controls. In contrast, mice transplanted with MSCV-P185wt-shRNA survived shorter than the control group. Gross pathological analysis revealed that the MSCV-P185wt-Runx1 group had less severe splenomegaly and hepatomegaly compared to the control group, and the MSCV-P185wt-shRNA group had more severe splenomegaly and hepatomegaly. No splenomegaly or hepatomegaly was detected in mice transplanted with MSCV-BaF3-Runxl cells or MSCV-BaF3-shRNA cells. Both the mice of MSCV-BaF3-Runxl group and MSCV-BaF3-shRNA group were healthy with no sign of leukemia for up to three months. Conclusions Overexpression or knock-down of Runxl gene in BaF3 cells alone could not induce leukemogenesis. However, in BaF3-P185wt cells, alteration of Runxl expression could affect BCR-ABL-induced proliferation and migration in vitro and leukemoaenesis in vivo.
