Background
Leukemic stem cells (LSCs) play an important role in the pathogenesis of leukemia. This research attempted to clarify effects of the telomere system on ginsenoside Rg1-induced senescence of LSCs. Objectives: This research attempted to clarify effects of the telomere system on ginsenoside Rg1-induced senescence of LSCs. Material and
Conclusions
Ginsenoside Rg1-induced senescence of CD34+CD38- LSCs through upregulating p16INK4a and downregulating hTERT expression, both of which are associated with telomere systems. The present study would be beneficial for the treatment of leukemia by providing a promising strategy to induce senescence of CD34+CD38- LSCs.
Material and methods
CD34+CD38- LSCs were isolated, sorted, and divided into a control group and a Rg1 group (treated with 40 μmol/L Rg1). Cell Counting Kit-8 (CCK-8) was used to evaluate cell proliferation, and flow cytometry was used to assess the cell cycle of CD34+CD38- LSCs. The senescence-associated β-galactosidase (SA-β-Gal) staining and CFU-Mix assay were conducted to measure senescence of CD34+CD38- LSCs. The mRNA transcription and protein expression of p16INK4a and human telomerase reverse transcriptase (hTERT) were determined using a real-time polymerase chain reaction (RT-PCR) and western blot assay, respectively.
Methods
CD34+CD38- LSCs were isolated, sorted, and divided into a control group and a Rg1 group (treated with 40 μmol/L Rg1). Cell Counting Kit-8 (CCK-8) was used to evaluate cell proliferation, and flow cytometry was used to assess the cell cycle of CD34+CD38- LSCs. The senescence-associated β-galactosidase (SA-β-Gal) staining and CFU-Mix assay were conducted to measure senescence of CD34+CD38- LSCs. The mRNA transcription and protein expression of p16INK4a and human telomerase reverse transcriptase (hTERT) were determined using a real-time polymerase chain reaction (RT-PCR) and western blot assay, respectively.
Results
The Rg1 treatment significantly attenuated proliferative activity and decreased the proliferative index (PI) of CD34+CD38- LSCs compared to those of the control group (p < 0.05). It remarkably increased positive SA-β-Gal staining rate, and suppressed formation of the CFU-Mix of CD34+CD38- LSCs compared with those of the control group (p < 0.05). The Rg1 treatment markedly boosted telomere effector, p16INK4a, in CD34+CD38- LSCs compared with that of control group (p < 0.05). Such treatment obviously reduced telomere regulator, hTERT, in CD34+CD38- LSCs compared with the control group (p < 0.05). Conclusions: Ginsenoside Rg1-induced senescence of CD34+CD38- LSCs through upregulating p16INK4a and downregulating hTERT expression, both of which are associated with telomere systems. The present study would be beneficial for the treatment of leukemia by providing a promising strategy to induce senescence of CD34+CD38- LSCs.