Limits...
Combined xanthorrhizol-curcumin exhibits synergistic growth inhibitory activity via apoptosis induction in human breast cancer cells MDA-MB-231.

Cheah YH, Nordin FJ, Sarip R, Tee TT, Azimahtol HL, Sirat HM, Rashid BA, Abdullah NR, Ismail Z - Cancer Cell Int. (2009)

Bottom Line: The effective dose that produced 50% growth inhibition (GI50) was calculated from the log dose-response curve of fixed-combinations of xanthorrhizol and curcumin generated from the sulforhodamine B (SRB) assay.Hoechst 33258 nuclear staining assay showed the rate of apoptosis of MDA-MB-231 cells to increase in response to the treatment.Apoptotic cell death was further confirmed by DNA fragmentation assay, where internucleosomal excision of DNA was induced upon treatment with xanthorrhizol-curcumin.

View Article: PubMed Central - HTML - PubMed

Affiliation: Bioassay Unit, Herbal Medicine Research Center, Institute for Medical Research, Jalan Pahang, Kuala Lumpur, Malaysia. yhcheah@gmail.com

ABSTRACT

Background: It has been suggested that combined effect of natural products may improve the treatment effectiveness in combating proliferation of cancer cells. The present study was undertaken to evaluate the possibility that the combination of xanthorrhizol and curcumin might show synergistic growth inhibitory effect towards MDA-MB-231 human breast cancer cells via apoptosis induction. The effective dose that produced 50% growth inhibition (GI50) was calculated from the log dose-response curve of fixed-combinations of xanthorrhizol and curcumin generated from the sulforhodamine B (SRB) assay. The experimental GI50 value was used to determine the synergistic activity of the combination treatment by isobolographic analysis and combination-index method. Further investigation of mode of cell death induced by the combination treatment was conducted in the present study.

Results: Isobole analysis revealed that substances interaction was synergistic when xanthorrhizol and curcumin were added concurrently to the cultures but merely additive when they were added sequentially. The synergistic combination treatment was then applied to the cultures to investigate the mode of cell death induced by the treatment. Immunofluorescence staining using antibody MitoCapturetrade mark revealed the possibility of altered mitochondrial transmembrane potential, which is one of the hallmark of apoptosis. Hoechst 33258 nuclear staining assay showed the rate of apoptosis of MDA-MB-231 cells to increase in response to the treatment. Apoptotic cell death was further confirmed by DNA fragmentation assay, where internucleosomal excision of DNA was induced upon treatment with xanthorrhizol-curcumin.

Conclusion: This is the first time the combined cytotoxic effect of xanthorrhizol and curcumin on MDA-MB-231 cells has been documented and our findings provide experimental support to the hypothesis that combined xanthorrhizol-curcumin showed synergistic growth inhibitory activity on MDA-MB-231 cells via apoptosis induction.

No MeSH data available.


Related in: MedlinePlus

Apoptosis level after treatment of xanthorrhizol and simultaneous treatment of xanthorrhizol-curcumin as determined from Hoechst 33258 staining. The treatment for 24 h induced exponential apoptotic cell death in a dose dependent manner as compare to untreated control. Results are presented as means ± SD of 3 independent experiments. *p < 0.05, **p < 0.005 statistically significant values relative to untreated control.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC2630298&req=5

Figure 4: Apoptosis level after treatment of xanthorrhizol and simultaneous treatment of xanthorrhizol-curcumin as determined from Hoechst 33258 staining. The treatment for 24 h induced exponential apoptotic cell death in a dose dependent manner as compare to untreated control. Results are presented as means ± SD of 3 independent experiments. *p < 0.05, **p < 0.005 statistically significant values relative to untreated control.

Mentions: The Hoechst 33258 dye was able to diffuse through intact membranes of MDA-MB-231 cells and stain their DNA. As the concentration of combined xanthorrhizol-curcumin increased, single intense fluorescence and multiple strong fluorescence signals were produced in the cell nuclei (Figure. 2B). The control culture (untreated MDA-MB-231) was uniformly stained with no substantial fluorescence signal, whereas the treated cells showed clear apoptotic morphology. According to the fluorescence and phase contrast images, shrinkage of cells and plasma membrane convolution were all observed in the treated cells. Similar apoptotic morphology was also observed in the MDA-MB-231 cells treated with 15 μg/ml xanthorrhizol (X). The number of apoptotic cells was determined and expressed as percentage of apoptotic index. Simultaneous treatment with combined xanthorrhizol-curcumin resulted in a dose dependent increase in apoptotic cells (Figure 4).


Combined xanthorrhizol-curcumin exhibits synergistic growth inhibitory activity via apoptosis induction in human breast cancer cells MDA-MB-231.

Cheah YH, Nordin FJ, Sarip R, Tee TT, Azimahtol HL, Sirat HM, Rashid BA, Abdullah NR, Ismail Z - Cancer Cell Int. (2009)

Apoptosis level after treatment of xanthorrhizol and simultaneous treatment of xanthorrhizol-curcumin as determined from Hoechst 33258 staining. The treatment for 24 h induced exponential apoptotic cell death in a dose dependent manner as compare to untreated control. Results are presented as means ± SD of 3 independent experiments. *p < 0.05, **p < 0.005 statistically significant values relative to untreated control.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC2630298&req=5

Figure 4: Apoptosis level after treatment of xanthorrhizol and simultaneous treatment of xanthorrhizol-curcumin as determined from Hoechst 33258 staining. The treatment for 24 h induced exponential apoptotic cell death in a dose dependent manner as compare to untreated control. Results are presented as means ± SD of 3 independent experiments. *p < 0.05, **p < 0.005 statistically significant values relative to untreated control.
Mentions: The Hoechst 33258 dye was able to diffuse through intact membranes of MDA-MB-231 cells and stain their DNA. As the concentration of combined xanthorrhizol-curcumin increased, single intense fluorescence and multiple strong fluorescence signals were produced in the cell nuclei (Figure. 2B). The control culture (untreated MDA-MB-231) was uniformly stained with no substantial fluorescence signal, whereas the treated cells showed clear apoptotic morphology. According to the fluorescence and phase contrast images, shrinkage of cells and plasma membrane convolution were all observed in the treated cells. Similar apoptotic morphology was also observed in the MDA-MB-231 cells treated with 15 μg/ml xanthorrhizol (X). The number of apoptotic cells was determined and expressed as percentage of apoptotic index. Simultaneous treatment with combined xanthorrhizol-curcumin resulted in a dose dependent increase in apoptotic cells (Figure 4).

Bottom Line: The effective dose that produced 50% growth inhibition (GI50) was calculated from the log dose-response curve of fixed-combinations of xanthorrhizol and curcumin generated from the sulforhodamine B (SRB) assay.Hoechst 33258 nuclear staining assay showed the rate of apoptosis of MDA-MB-231 cells to increase in response to the treatment.Apoptotic cell death was further confirmed by DNA fragmentation assay, where internucleosomal excision of DNA was induced upon treatment with xanthorrhizol-curcumin.

View Article: PubMed Central - HTML - PubMed

Affiliation: Bioassay Unit, Herbal Medicine Research Center, Institute for Medical Research, Jalan Pahang, Kuala Lumpur, Malaysia. yhcheah@gmail.com

ABSTRACT

Background: It has been suggested that combined effect of natural products may improve the treatment effectiveness in combating proliferation of cancer cells. The present study was undertaken to evaluate the possibility that the combination of xanthorrhizol and curcumin might show synergistic growth inhibitory effect towards MDA-MB-231 human breast cancer cells via apoptosis induction. The effective dose that produced 50% growth inhibition (GI50) was calculated from the log dose-response curve of fixed-combinations of xanthorrhizol and curcumin generated from the sulforhodamine B (SRB) assay. The experimental GI50 value was used to determine the synergistic activity of the combination treatment by isobolographic analysis and combination-index method. Further investigation of mode of cell death induced by the combination treatment was conducted in the present study.

Results: Isobole analysis revealed that substances interaction was synergistic when xanthorrhizol and curcumin were added concurrently to the cultures but merely additive when they were added sequentially. The synergistic combination treatment was then applied to the cultures to investigate the mode of cell death induced by the treatment. Immunofluorescence staining using antibody MitoCapturetrade mark revealed the possibility of altered mitochondrial transmembrane potential, which is one of the hallmark of apoptosis. Hoechst 33258 nuclear staining assay showed the rate of apoptosis of MDA-MB-231 cells to increase in response to the treatment. Apoptotic cell death was further confirmed by DNA fragmentation assay, where internucleosomal excision of DNA was induced upon treatment with xanthorrhizol-curcumin.

Conclusion: This is the first time the combined cytotoxic effect of xanthorrhizol and curcumin on MDA-MB-231 cells has been documented and our findings provide experimental support to the hypothesis that combined xanthorrhizol-curcumin showed synergistic growth inhibitory activity on MDA-MB-231 cells via apoptosis induction.

No MeSH data available.


Related in: MedlinePlus