Limits...
Cucurbitacin B Causes Increased Radiation Sensitivity of Human Breast Cancer Cells via G2/M Cell Cycle Arrest.

Duangmano S, Sae-Lim P, Suksamrarn A, Patmasiriwat P, Domann FE - J Oncol (2012)

Bottom Line: Results.Flow cytometric analysis for DNA content indicated that cucurbitacin B resulted in G2/M arrest in MDA-MB-231 and MCF7:5C but not SKBR-3 cells.Therefore, combinations of cucurbitacin B with radiotherapy may be appropriate for experimental breast cancer treatment.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Medical Technology, Mahidol University, Bangkok, Thailand.

ABSTRACT
Purpose. To explore the effects of cucurbitacin B on the radiation survival of human breast cancer cells and to elucidate the cellular mechanism of radiosensitization if any. Materials and Methods. Human breast carcinoma cell lines were treated with cucurbitacin B before irradiation with 0-10 Gy of (137)Cs gamma rays. The effect of cucurbitacin B on cell-survival following irradiation was evaluated by colony-forming assay. Cell cycle distributions were investigated using flow cytometry. Real-time PCR and western blots were performed to investigate the expression of cell cycle checkpoints. Results. Cucurbitacin B inhibited breast cancer cell proliferation in a dose-dependent manner. Only MDA-MB-231 and MCF7:5C cells but not SKBR-3 cells were radiosensitized by cucurbitacin B. Flow cytometric analysis for DNA content indicated that cucurbitacin B resulted in G2/M arrest in MDA-MB-231 and MCF7:5C but not SKBR-3 cells. Moreover, Real-time PCR and western blot analysis demonstrated upregulated p21 expression before irradiation, a likely cause of the cell cycle arrest. Conclusion. Taken together, these findings suggest that cucurbitacin B causes radiosensitization of some breast cancer cells, and that cucurbitacin B induced G2/M arrest is an important mechanism. Therefore, combinations of cucurbitacin B with radiotherapy may be appropriate for experimental breast cancer treatment.

No MeSH data available.


Related in: MedlinePlus

Effect of cucurbitacin B on p21 gene expression. MCF7:5C, MDA-MB-231, and SKBR-3 were incubated for 48 hr with the specified concentrations of cucurbitacin B, and RNA was extracted for real-time PCR to quantitate the expression level of p21. Relative expression levels of p21 mRNA at indicated concentration. Results shown are the average of three independent experiments. *P < 0.05 versus nontreated control, **P < 0.01 versus nontreated control.
© Copyright Policy - open-access
Related In: Results  -  Collection


getmorefigures.php?uid=PMC3368438&req=5

fig4: Effect of cucurbitacin B on p21 gene expression. MCF7:5C, MDA-MB-231, and SKBR-3 were incubated for 48 hr with the specified concentrations of cucurbitacin B, and RNA was extracted for real-time PCR to quantitate the expression level of p21. Relative expression levels of p21 mRNA at indicated concentration. Results shown are the average of three independent experiments. *P < 0.05 versus nontreated control, **P < 0.01 versus nontreated control.

Mentions: To determine the effect of cucurbitacin B on p21 mRNA expression, all three cell lines were incubated with cucurbitacin B for 48 hr, in parallel with untreated cell. Exposure of MCF7:5C, MDA-MB-231, and SKBR-3 cell lines to 2.5 μM and 5 μM of cucurbitacin B resulted in the progressive increase p21 mRNA level. SKBR-3 shows the highest induction of p21 mRNA expression after cucurbitacin B treatment. The expression p21 mRNA in SKBR-3 was increased up to 20 times when compared with untreated cell while MCF7:5C and MDA-MB-231 was increased 3-4 times as shown in Figure 4(a). The real-time PCR products were applied on 0.8% agarose gel containing ethidium bromide (EtBr) to scrutinize that the PCR reaction was specific and that cucurbitacin B induced gene expression of p21.


Cucurbitacin B Causes Increased Radiation Sensitivity of Human Breast Cancer Cells via G2/M Cell Cycle Arrest.

Duangmano S, Sae-Lim P, Suksamrarn A, Patmasiriwat P, Domann FE - J Oncol (2012)

Effect of cucurbitacin B on p21 gene expression. MCF7:5C, MDA-MB-231, and SKBR-3 were incubated for 48 hr with the specified concentrations of cucurbitacin B, and RNA was extracted for real-time PCR to quantitate the expression level of p21. Relative expression levels of p21 mRNA at indicated concentration. Results shown are the average of three independent experiments. *P < 0.05 versus nontreated control, **P < 0.01 versus nontreated control.
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC3368438&req=5

fig4: Effect of cucurbitacin B on p21 gene expression. MCF7:5C, MDA-MB-231, and SKBR-3 were incubated for 48 hr with the specified concentrations of cucurbitacin B, and RNA was extracted for real-time PCR to quantitate the expression level of p21. Relative expression levels of p21 mRNA at indicated concentration. Results shown are the average of three independent experiments. *P < 0.05 versus nontreated control, **P < 0.01 versus nontreated control.
Mentions: To determine the effect of cucurbitacin B on p21 mRNA expression, all three cell lines were incubated with cucurbitacin B for 48 hr, in parallel with untreated cell. Exposure of MCF7:5C, MDA-MB-231, and SKBR-3 cell lines to 2.5 μM and 5 μM of cucurbitacin B resulted in the progressive increase p21 mRNA level. SKBR-3 shows the highest induction of p21 mRNA expression after cucurbitacin B treatment. The expression p21 mRNA in SKBR-3 was increased up to 20 times when compared with untreated cell while MCF7:5C and MDA-MB-231 was increased 3-4 times as shown in Figure 4(a). The real-time PCR products were applied on 0.8% agarose gel containing ethidium bromide (EtBr) to scrutinize that the PCR reaction was specific and that cucurbitacin B induced gene expression of p21.

Bottom Line: Results.Flow cytometric analysis for DNA content indicated that cucurbitacin B resulted in G2/M arrest in MDA-MB-231 and MCF7:5C but not SKBR-3 cells.Therefore, combinations of cucurbitacin B with radiotherapy may be appropriate for experimental breast cancer treatment.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Medical Technology, Mahidol University, Bangkok, Thailand.

ABSTRACT
Purpose. To explore the effects of cucurbitacin B on the radiation survival of human breast cancer cells and to elucidate the cellular mechanism of radiosensitization if any. Materials and Methods. Human breast carcinoma cell lines were treated with cucurbitacin B before irradiation with 0-10 Gy of (137)Cs gamma rays. The effect of cucurbitacin B on cell-survival following irradiation was evaluated by colony-forming assay. Cell cycle distributions were investigated using flow cytometry. Real-time PCR and western blots were performed to investigate the expression of cell cycle checkpoints. Results. Cucurbitacin B inhibited breast cancer cell proliferation in a dose-dependent manner. Only MDA-MB-231 and MCF7:5C cells but not SKBR-3 cells were radiosensitized by cucurbitacin B. Flow cytometric analysis for DNA content indicated that cucurbitacin B resulted in G2/M arrest in MDA-MB-231 and MCF7:5C but not SKBR-3 cells. Moreover, Real-time PCR and western blot analysis demonstrated upregulated p21 expression before irradiation, a likely cause of the cell cycle arrest. Conclusion. Taken together, these findings suggest that cucurbitacin B causes radiosensitization of some breast cancer cells, and that cucurbitacin B induced G2/M arrest is an important mechanism. Therefore, combinations of cucurbitacin B with radiotherapy may be appropriate for experimental breast cancer treatment.

No MeSH data available.


Related in: MedlinePlus