• Proceedings of the Korea Environmental Mutagen Society Conference
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• 2002.05a
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• pp.91-91
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• 2002

• Archives of Pharmacal Research
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• v.28 no.7
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• pp.823-828
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• 2005

Multidrug resistance (MDR) is one of the most significant obstacles in cancer chemotherapy. One of the mechanisms involved in the development of MDR is the over-expression of P-glycoprotein (P-gp). It is widely known that natural compounds found in vegetables, fruits, plant-derived beverages and herbal dietary supplements not only have anticancer properties, but may also modulate P-gp activity. Therefore, the purpose of this investigation was to examine the effects of naturally occurring products on P-gp function in human breast cancer cell lines, MCF-7 (sensitive) and MCF-7/ADR (resistant). The accumulation of daunomycin (DNM), a P-gp substrate, was greater in the sensitive cells compared to the resistant cells, while the efflux of DNM was higher in the resistant cells compared to the sensitive cells over a period of 2h. The $IC_{50}$ value of DNM in the resistant cells was about 22 times higher than that in the sensitive cells, indicating an over-expression of P-gp in the resistant cells, MCF-7/ADR. All of the compounds tested, with the exception of fisetin, significantly decreased the $IC_{50}$ value of DNM. Biochanin A showed the greatest increase in $[^3H]-DNM$ accumulation, increasing by $454.3{\pm}19.5%$ in the resistant cells, whereas verapamil, the positive control, increased the accumulation by $229.4{\pm}17.6%$. Also, the accumulation of $[^3H]-DNM$ was increased substantially by quercetin and silymarin while it was reduced by fisetin. Moreover, biochanin A, silymarin, and naringenin significantly decreased DNM efflux from MCF-7/ADR cells compared with the control. These results suggest that some flavonoids such as biochanin A and silymarin may reverse MDR by inhibiting the P-gp function.

• Journal of Life Science
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• v.19 no.2
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• pp.157-162
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• 2009

Nitric oxide (NO) is a diffusible, multifunctional and transcellular messenger that has been implicated in numerous physiological and pathological conditions. It has been reported that NO induced apoptosis in tumor cells, macrophage cells and inhibited apoptosis in normal cells, endothelial cells. To examine whether NO could induce apoptosis in MCF-7 cells, cells were treated with SIN-1 (3-morpholinosydnonimine), NO donor. Cell viability did not change in SIN-1 treated cells for 48 h and there was no significantly changes in cell cycle progression or growth pattern by FACS analysis. But p53 protein, an apoptosis-related factor, increased SIN-1 treatment time dependently. Bcl-2, MDM2 and p21 were also accumulated. Bax level did not change. A major role of inhibiting apoptosis by NO in MCF-7 cells, cobalt chloride ($CoCl_2$) was added to cells preincubated with SIN-1. Whereas $CoCl_2$ treated cells underwent apoptosis, for 24 h SIN-1 preincubated cells were not induced apoptosis. Inactivated proteins, MDM2 and bcl-2, by $CoCl_2$ levels also increased in SIN-1 pre-treated cells. These results suggested that SIN-1 blocked p53 by MDM2 activation and inhibited apoptosis by inducing p21 and bcl-2 expression.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9655-9660
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• 2014

Background: Nigella Sativa (NS) is an herb from the Ranunculaceae family that exhibits numerous medicinal properties and has been used as important constituent of many complementary and alternative medicines (CAMs). The ability of NS to kill cancer cells such as PC3, HeLa and hepatoma cells is well established. However, our understanding of the mode of death caused by NS remains nebulous. The objective of this study was to gain further insight into the mode and mechanism of death caused by NS in breast cancer MCF-7 cells. Materials and Methods: Human breast cancer cells (MCF-7) were treated with a methanolic extract of NS, and a dose- and time-dependent study was performed. The $IC_{50}$ was calculated using a Cell Titer $Blue^{(R)}$ viability assay assay, and evidence for DNA fragmentation was obtained by fluorescence microscopy TUNEL assay. Gene expression was also profiled for a number of apoptosis-related genes (Caspase-3, -8, -9 and p53 genes) through qPCR. Results: The $IC_{50}$ of MCF-7 cells was $62.8{\mu}L/mL$. When MCF-7 cells were exposed to $50{\mu}L/mL$ and $100{\mu}L/mL$ NS for 24h, 48h and 72h, microscopic examination (TUNEL assay) revealed a dose- and time-dependent increase in apoptosis. Similarly, the expression of the Caspase-3, -8, -9 and p53 genes increased significantly according to the dose and time. Conclusions: NS induced apoptosis in MCF-7 cells through both the p53 and caspase pathways. NS could potentially represent an alternative source of medicine for breast cancer therapy.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.131-134
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• 2016

Breast cancer is the most common malignancy and also the second leading cause of cancer death among women and also in women that have a high mortality. Previous studies showed that magnesium (Mg) has cytotoxic effects on malignant cell lines. However, the anti-cancer effects of Mg on MCF-7 breast cancer cells are uncertain. This study was aimed at the comparison of the cytotoxic effect of Mg salt (MgCl2) and cisplatin on MCF-7 cells and fibroblasts (as normal cells). After treatment with various concentrations of MgCl2, and cisplatin as a positive control for 24 and 48 hours (h), cytotoxicity activity was measured by MTT assay. In addition, apoptosis was determined by annexin V/propidium iide assay. Both cisplatin and the MgCl2 exhibited dose-dependent cytotoxic effects in the MCF-7 cell line, although the LD50 of the Mg was significantly higher when compared to cispaltin ($40{\mu}g/ml$ vs. $20{\mu}g/ml$). Regarding annexin V/propidium results, treatment of MCF-7 cells with LD50 concentrations of cisplatin and Mg showed 59% and 44% apoptosis at 24h, respectively. Finally, the results indicated that Mg has cytotoxic effects on MCF-7 cells, but less than cisplatin as a conventional chemotherapeutic agent. However, regarding the side effects of chemotherapy drugs, it seems that Mg can be considered as a supplement for the treatment of breast cancer.

• Journal of Ginseng Research
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• v.43 no.4
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• pp.527-538
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• 2019

Background: Ginsenoside Rg1 was shown to exert ligand-independent activation of estrogen receptor (ER) via mitogen-activated protein kinase-mediated pathway. Our study aimed to delineate the mechanisms by which Rg1 activates the rapid ER signaling pathways. Methods: ER-positive human breast cancer MCF-7 cells and ER-negative human embryonic kidney HEK293 cells were treated with Rg1 ($10^{-12}M$, $10^{-8}M$), $17{\beta}$-estradiol ($10^{-8}M$), or vehicle. Immunoprecipitation was conducted to investigate the interactions between signaling protein and ER in MCF-7 cells. To determine the roles of these signaling proteins in the actions of Rg1, small interfering RNA or their inhibitors were applied. Results: Rg1 rapidly induced $ER{\alpha}$ translocation to plasma membrane via caveolin-1 and the formation of signaling complex involving linker protein (Shc), insulin-like growth factor-I receptor, modulator of nongenomic activity of ER (MNAR), $ER{\alpha}$, and cellular nonreceptor tyrosine kinase (c-Src) in MCF-7 cells. The induction of extracellular signal-regulated protein kinase and mitogen-activated protein kinase kinase (MEK) phosphorylation in MCF-7 cells by Rg1 was suppressed by cotreatment with small interfering RNA against these signaling proteins. The stimulatory effects of Rg1 on MEK phosphorylation in these cells were suppressed by both PP2 (Src kinase inhibitor) and AG1478 [epidermal growth factor receptor (EGFR) inhibitor]. In addition, Rg1-induced estrogenic activities, EGFR and MEK phosphorylation in MCF-7 cells were abolished by cotreatment with G15 (G protein-coupled estrogen receptor-1 antagonist). The increase in intracellular cyclic AMP accumulation, but not Ca mobilization, in MCF-7 cells by Rg1 could be abolished by G15. Conclusion: Ginsenoside Rg1 exerted estrogenic actions by rapidly inducing the formation of ER containing signalosome in MCF-7 cells. Additionally, Rg1 could activate EGFR and c-Src ER-independently and exert estrogenic effects via rapid activation of membrane-associated ER and G protein-coupled estrogen receptor.

• Biomedical Science Letters
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• v.17 no.3
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• pp.261-265
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• 2011

Parkin is a putative tumor suppressor protein and its expression is frequently reduced or absent in several types of tumors. In this study, we examined the role of Parkin in mRNA expression of monocyte chemotactic protein-1 (MCP-1) in the breast cancer cell line MCF7. Expression of MCP-1 mRNA increased after TNF-${\alpha}$ treatment. However, overexpression of Parkin induced a decrease in expression of MCP-1 mRNA in TNF-${\alpha}$-stimulated MCF7. This decrease in MCP-1 mRNA by Parkin overexpression occurred in a dose- and time-dependent manner. Using a wound scratch assay, we found that Parkin overexpression in MCF7 cells also resulted in a decrease in cell migration. These results suggest that Parkin down-regulates MCP-1 synthesis leading to decreased migration of tumor cells. We suggest that one possible mechanism by which Parkin acts as a tumor suppressor is by inhibiting migration or metastasis of cancer cells.

• Korean Journal of Environmental Biology
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• v.21 no.1
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• pp.52-55
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• 2003

There is considerable evidence that ionizing radiation (IR) mediates checkpoint control, repair and cell death. In this study, we have used a high density microarray hybridization approach to characterize the transcriptional response of human breast carcinoma MCF-7 cell line to ${\gamma}$-radiation, such as 4 Gy 4 hr, 8 Gy 4 hr, and 8 Gy 12 hr. We found that exposure to ${\gamma}$-ray alters by at least a $log_2$ factor of 1.0 the expression of 115 known genes. Of the 66 genes affected by ${\gamma}$-radiation, 49 are down-regulated. In our results, the cellular response to irradiation includes induction of the c-jun and EGR1 early response genes. The present work has examined potential cytoplasmic signaling cascades that transduce IR-induced signals to the nucleus. 40S ribosomal protein s6 kinase modulates the activities of the mitogen activated protein kinase (MAPK) and c-Jun $NH_2$-terminal kinase (JNK1) cascades in human monocytic leukemia (U937/pREP4) cells. 14-3-3 family members are dimeric phosphoserine -binding proteins that participate in signal transduction and checkpoint control pathways.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.10
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• pp.4311-4317
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• 2014

Background: Nano-biotechnology is recognized as offering revolutionary changes in the field of cancer therapy and biologically synthesized gold nanoparticles are known to have a wide range of medical applications. Materials and Methods: Gold nanoparticles (GNPs) were biosynthesized with an aqueous extract of the red alga Corallina officinalis, used as a reducing and stabilizing agent. GNPs were characterized using UV-Vis spectroscopy, transmission electron microscopy (TEM), energy dispersive analysis (EDX) and Fourier transform infra-red (FT-IR) spectroscopy and tested for cytotoxic activity against human breast cancer (MCF-7) cells cultured in Dulbecco's modified Eagle medium supplemented with 10% fetal bovine serum, considering their cytotoxicty and effects on cellular DNA. Results: The biosynthesized GNPs were $14.6{\pm}1nm$ in diameter. FT-IR analysis showed that the hydroxyl functional group from polyphenols and carbonyl group from proteins could assist in formation and stabilization. The GNPs showed potent cytotoxic activity against MCF-7 cells, causing necrosis at high concentrations while lower concentrations were without effect as indicated by DNA fragmentation assay. Conclusions: The antitumor activity of the biosynthesized GNPs from the red alga Corallina officinalis against human breast cancer cells may be due to the cytotoxic effects of the gold nanoparticles and the polyphenolcontent of the algal extract.

• Biomedical Science Letters
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• v.23 no.3
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• pp.290-294
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• 2017

Metformin or sodium salicylate is known to induce apoptosis and G0/G1 phase arrest in a variety of cancer cells. However, the anti-cancer effects of the combined treatments for these drugs-induced apoptosis are yet unclear. Here, we found that the combined treatment of metformin and sodium salicylate increased the efficacy of chemotherapeutics against breast cancer cells. These combined drugs significantly inhibited cellular proliferation and induced apoptosis at an earlier stage in human MCF-7 breast cancer cells. Also, co-treatments of metformin and sodium salicylate induced G1 cell cycle arrest in MCF-7 cells more effectively than either agent alone. Taken together, these results demonstrate that dual metformin/sodium salicylate treatment prevents proliferation of MCF-7 cells by inducing apoptosis and G1 cell cycle arrest.