Limits...
Catechins induced acute promyelocytic leukemia cell apoptosis and triggered PML-RARα oncoprotein degradation.

Zhang L, Chen QS, Xu PP, Qian Y, Wang AH, Xiao D, Zhao Y, Sheng Y, Wen XQ, Zhao WL - J Hematol Oncol (2014)

Bottom Line: It has recently been reported that the extracts of green tea polyphenol have cancer preventive effects.Catechins-mediated apoptotic effect was also observed in primary APL cells without affecting normal hematopoietic progenitor cells.Catechins might be a potential candidate for APL treatment by activating intrinsic apoptotic pathway and targeting PML-RARα oncoprotein.

View Article: PubMed Central - PubMed

ABSTRACT

Background: It has recently been reported that the extracts of green tea polyphenol have cancer preventive effects. In this study, we investigated the effect of the natural composition from green tea leaves Catechins on acute promyelocytic leukemia (APL).

Methods: In vitro, APL cell lines NB4, retinoic acid-resistant NB4-R1 and NB4-R2 were treated with different concentrations of Catechins. Cell viability and cell apoptosis were analyzed using MTT assay and flow cytometric assay, respectively. Expression of proteins related to apoptosis and PML-RARα oncoprotein were assessed by Western blot. In vivo anti-tumor activity of Catechins was examined in nude mice xenografted with NB4 cells and in situ cell apoptosis was detected by terminal deoxytransferase-catalyzed DNA nick-end labeling assay.

Results: Catechins at micromolar concentration levels significantly inhibited APL cell proliferation and induced cell apoptosis, in association with mitochondria damage, ROS production and caspase activation. The anti-apoptotic Bcl-2 family member Bcl-xL was down regulated, with pro-apoptotic member Bax remaining unchanged. Moreover, Catechins induced the degradation of PML-RARα oncoprotein. Catechins-mediated apoptotic effect was also observed in primary APL cells without affecting normal hematopoietic progenitor cells. In the murine xenograft model, Catechins remarkably inhibited tumor growth and induced in situ leukemic cell apoptosis.

Conclusions: Catechins might be a potential candidate for APL treatment by activating intrinsic apoptotic pathway and targeting PML-RARα oncoprotein.

Show MeSH

Related in: MedlinePlus

The effect of Catechins treatment on growth and apoptosis of human leukemia cell lines. (A) IC50 results obtained from MTT assay in leukemia cell lines treated with Catechins at 24 h. The IC50 values of NB4-R1, NB4-R2 and NB4 cells were below 125 μM. (B) The growth inhibition of NB4-R1, NB4-R2 and NB4 cells treated with Catechins for 24 and 48 h. Reduced cell viability were detected in APL cell lines from 50 μM Catechins. (C) Characteristic apoptotic cells were present in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM or 200 μM Catechins for 24 h. (D) Detection of apoptotic cells by Annexin V-FITC/PI double staining in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM Catechins for 24 and 48 h. Catechins treatment increased the percentages of Annexin-V+/PI- cells (lower right quadrant) and Annexin-V+/PI + cells (upper right quadrant). (E) Contribution of nuclear DNA content in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM Catechins for 24 h and 48 h. Significantly increased sub-G1 cells were observed. *P < 0.05, **P < 0.01, ***P < 0.001 comparing with the untreated cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4197244&req=5

Fig1: The effect of Catechins treatment on growth and apoptosis of human leukemia cell lines. (A) IC50 results obtained from MTT assay in leukemia cell lines treated with Catechins at 24 h. The IC50 values of NB4-R1, NB4-R2 and NB4 cells were below 125 μM. (B) The growth inhibition of NB4-R1, NB4-R2 and NB4 cells treated with Catechins for 24 and 48 h. Reduced cell viability were detected in APL cell lines from 50 μM Catechins. (C) Characteristic apoptotic cells were present in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM or 200 μM Catechins for 24 h. (D) Detection of apoptotic cells by Annexin V-FITC/PI double staining in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM Catechins for 24 and 48 h. Catechins treatment increased the percentages of Annexin-V+/PI- cells (lower right quadrant) and Annexin-V+/PI + cells (upper right quadrant). (E) Contribution of nuclear DNA content in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM Catechins for 24 h and 48 h. Significantly increased sub-G1 cells were observed. *P < 0.05, **P < 0.01, ***P < 0.001 comparing with the untreated cells.

Mentions: Using MTT assay, we determined the effect of Catechins on various human leukemia cell lines. The IC50 value (median inhibitory concentration) of Catechins in these leukemia cells were calculated after 24 hours of treatment. Catechins exerted substantial growth inhibition in APL cell lines (NB4-R1, NB4-R2 and NB4), Kasumi-1 cells and K562 cells (Figure 1A). However, the sensitivity of U937 cells to Catechins was relatively lower, with IC50 higher than 200 μM.Figure 1


Catechins induced acute promyelocytic leukemia cell apoptosis and triggered PML-RARα oncoprotein degradation.

Zhang L, Chen QS, Xu PP, Qian Y, Wang AH, Xiao D, Zhao Y, Sheng Y, Wen XQ, Zhao WL - J Hematol Oncol (2014)

The effect of Catechins treatment on growth and apoptosis of human leukemia cell lines. (A) IC50 results obtained from MTT assay in leukemia cell lines treated with Catechins at 24 h. The IC50 values of NB4-R1, NB4-R2 and NB4 cells were below 125 μM. (B) The growth inhibition of NB4-R1, NB4-R2 and NB4 cells treated with Catechins for 24 and 48 h. Reduced cell viability were detected in APL cell lines from 50 μM Catechins. (C) Characteristic apoptotic cells were present in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM or 200 μM Catechins for 24 h. (D) Detection of apoptotic cells by Annexin V-FITC/PI double staining in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM Catechins for 24 and 48 h. Catechins treatment increased the percentages of Annexin-V+/PI- cells (lower right quadrant) and Annexin-V+/PI + cells (upper right quadrant). (E) Contribution of nuclear DNA content in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM Catechins for 24 h and 48 h. Significantly increased sub-G1 cells were observed. *P < 0.05, **P < 0.01, ***P < 0.001 comparing with the untreated cells.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4197244&req=5

Fig1: The effect of Catechins treatment on growth and apoptosis of human leukemia cell lines. (A) IC50 results obtained from MTT assay in leukemia cell lines treated with Catechins at 24 h. The IC50 values of NB4-R1, NB4-R2 and NB4 cells were below 125 μM. (B) The growth inhibition of NB4-R1, NB4-R2 and NB4 cells treated with Catechins for 24 and 48 h. Reduced cell viability were detected in APL cell lines from 50 μM Catechins. (C) Characteristic apoptotic cells were present in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM or 200 μM Catechins for 24 h. (D) Detection of apoptotic cells by Annexin V-FITC/PI double staining in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM Catechins for 24 and 48 h. Catechins treatment increased the percentages of Annexin-V+/PI- cells (lower right quadrant) and Annexin-V+/PI + cells (upper right quadrant). (E) Contribution of nuclear DNA content in NB4-R1, NB4-R2 and NB4 cells treated with 100 μM Catechins for 24 h and 48 h. Significantly increased sub-G1 cells were observed. *P < 0.05, **P < 0.01, ***P < 0.001 comparing with the untreated cells.
Mentions: Using MTT assay, we determined the effect of Catechins on various human leukemia cell lines. The IC50 value (median inhibitory concentration) of Catechins in these leukemia cells were calculated after 24 hours of treatment. Catechins exerted substantial growth inhibition in APL cell lines (NB4-R1, NB4-R2 and NB4), Kasumi-1 cells and K562 cells (Figure 1A). However, the sensitivity of U937 cells to Catechins was relatively lower, with IC50 higher than 200 μM.Figure 1

Bottom Line: It has recently been reported that the extracts of green tea polyphenol have cancer preventive effects.Catechins-mediated apoptotic effect was also observed in primary APL cells without affecting normal hematopoietic progenitor cells.Catechins might be a potential candidate for APL treatment by activating intrinsic apoptotic pathway and targeting PML-RARα oncoprotein.

View Article: PubMed Central - PubMed

ABSTRACT

Background: It has recently been reported that the extracts of green tea polyphenol have cancer preventive effects. In this study, we investigated the effect of the natural composition from green tea leaves Catechins on acute promyelocytic leukemia (APL).

Methods: In vitro, APL cell lines NB4, retinoic acid-resistant NB4-R1 and NB4-R2 were treated with different concentrations of Catechins. Cell viability and cell apoptosis were analyzed using MTT assay and flow cytometric assay, respectively. Expression of proteins related to apoptosis and PML-RARα oncoprotein were assessed by Western blot. In vivo anti-tumor activity of Catechins was examined in nude mice xenografted with NB4 cells and in situ cell apoptosis was detected by terminal deoxytransferase-catalyzed DNA nick-end labeling assay.

Results: Catechins at micromolar concentration levels significantly inhibited APL cell proliferation and induced cell apoptosis, in association with mitochondria damage, ROS production and caspase activation. The anti-apoptotic Bcl-2 family member Bcl-xL was down regulated, with pro-apoptotic member Bax remaining unchanged. Moreover, Catechins induced the degradation of PML-RARα oncoprotein. Catechins-mediated apoptotic effect was also observed in primary APL cells without affecting normal hematopoietic progenitor cells. In the murine xenograft model, Catechins remarkably inhibited tumor growth and induced in situ leukemic cell apoptosis.

Conclusions: Catechins might be a potential candidate for APL treatment by activating intrinsic apoptotic pathway and targeting PML-RARα oncoprotein.

Show MeSH
Related in: MedlinePlus