Contributions
Abstract: PB1671
Type: Publication Only
Background
Leukemia cells are limitless cell sources for initiation and maintenance of leukemia. Telomere-binding proteins are key regulatory factors for various diseases, including leukemia. Therefore, targeting telomere-binding proteins is considered as a promising therapeutic strategy for treatment of leukemia.
Aims
We aimed to explore whether quercetin, a natural flavonoids, could regulate telomere-binding proteins expression to inhibit proliferation and induce apoptosis in acute myeloid leukemia(AML) THP-1 cells.
Methods
1. In vitro: (1) We cultured human AML THP-1 cells. (2) The cells were treated with different concentration of quercetin for 24/48 h, and the cell viability was measured by cell counting kit-8(CCK-8) to determine the IC50 of quercetin. (3) The cell cycle distribution and apoptotic rate were measured by Annexin V-FITC/PI double staining flow cytometry(FCM). (4) The protein expression levels of POT1, TRF1, TRF2 were measured by western-blotting. (5) The mRNA expression levels of POT1, TRF1, TRF2 were measured by real-time fluorescent quantitative polymerase chain reaction(RT-qPCR). 2 In vivo: (1) Established AML-NOD/SCID model based on THP-1 cell line in NOD/SCID mice, and treated with optimal quercetin concentration 40mg/(kg*d) for 4 weeks by tail vein injection. (2)We observed the changes of mice survival status, peripheral blood and bone marrow cell morphology and organ histopathology by microscopy before and after treatment with quercetin. (3) The cell cycle distribution and apoptotic rate of spleen cells were measured by Annexin V-FITC/PI double staining FCM. The protein expression levels of POT1, TRF1, TRF2 were measured by immunohistochemistry(IHC) staining.
Results
In this study, we found that quercetin significantly suppressed THP-1 cells proliferation in dose- and time-dependent manner. Treatment with quercetin significantly increased THP-1 cells apoptotic rate and G1 phase arrest rate. Furthermore, the protein expression levels of POT1 and TRF1 increased and the protein expression level of TRF2 decreased. The mRNA expression levels of POT1, TRF1, TRF2 were consistent with their protein expression levels, respectively.
Conclusion
Our results demonstrate that quercetin has anti-leukemia activity. It is mediated by regulating telomere-binding proteins expression of POT1, TRF1 and TRF2. Taken together, our findings support the concept that quercetin is a promising therapeutic strategy for treatment of leukemia.
Session topic: 3. Acute myeloid leukemia - Biology
Keyword(s): Acute Myeloid Leukemia, Telomere, Leukemia cell line
Abstract: PB1671
Type: Publication Only
Background
Leukemia cells are limitless cell sources for initiation and maintenance of leukemia. Telomere-binding proteins are key regulatory factors for various diseases, including leukemia. Therefore, targeting telomere-binding proteins is considered as a promising therapeutic strategy for treatment of leukemia.
Aims
We aimed to explore whether quercetin, a natural flavonoids, could regulate telomere-binding proteins expression to inhibit proliferation and induce apoptosis in acute myeloid leukemia(AML) THP-1 cells.
Methods
1. In vitro: (1) We cultured human AML THP-1 cells. (2) The cells were treated with different concentration of quercetin for 24/48 h, and the cell viability was measured by cell counting kit-8(CCK-8) to determine the IC50 of quercetin. (3) The cell cycle distribution and apoptotic rate were measured by Annexin V-FITC/PI double staining flow cytometry(FCM). (4) The protein expression levels of POT1, TRF1, TRF2 were measured by western-blotting. (5) The mRNA expression levels of POT1, TRF1, TRF2 were measured by real-time fluorescent quantitative polymerase chain reaction(RT-qPCR). 2 In vivo: (1) Established AML-NOD/SCID model based on THP-1 cell line in NOD/SCID mice, and treated with optimal quercetin concentration 40mg/(kg*d) for 4 weeks by tail vein injection. (2)We observed the changes of mice survival status, peripheral blood and bone marrow cell morphology and organ histopathology by microscopy before and after treatment with quercetin. (3) The cell cycle distribution and apoptotic rate of spleen cells were measured by Annexin V-FITC/PI double staining FCM. The protein expression levels of POT1, TRF1, TRF2 were measured by immunohistochemistry(IHC) staining.
Results
In this study, we found that quercetin significantly suppressed THP-1 cells proliferation in dose- and time-dependent manner. Treatment with quercetin significantly increased THP-1 cells apoptotic rate and G1 phase arrest rate. Furthermore, the protein expression levels of POT1 and TRF1 increased and the protein expression level of TRF2 decreased. The mRNA expression levels of POT1, TRF1, TRF2 were consistent with their protein expression levels, respectively.
Conclusion
Our results demonstrate that quercetin has anti-leukemia activity. It is mediated by regulating telomere-binding proteins expression of POT1, TRF1 and TRF2. Taken together, our findings support the concept that quercetin is a promising therapeutic strategy for treatment of leukemia.
Session topic: 3. Acute myeloid leukemia - Biology
Keyword(s): Acute Myeloid Leukemia, Telomere, Leukemia cell line