(-)-Epigallocatechin-3-gallate downregulates Pg-P and BCRP in a tamoxifen resistant MCF-7 cell line

Farabegoli, Fulvia; Papi, Alessio; Bartolini, G; Ostan, Rita; Orlandi, Marina

doi:10.1016/j.phymed.2010.01.001

Cited by 109 publications

(70 citation statements)

References 31 publications

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“…Following exposure to 100 µg̸ml EGCG for 24 h, the expression of Bax was increased and the expression of Bcl-2 was decreased (40). A recent study also reported that microRNA expression in MCF-7 cells may be affected by green tea, which is rich in catechins and caffeine, resulting in inhibition of carcinogenesis (41).…”

Section: Discussionmentioning

confidence: 99%

Effect of Paullinia cupana on MCF-7 breast cancer cell response to chemotherapeutic drugs

Hertz

Cadoná

Machado

et al. 2014

Molecular and Clinical Oncology

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Abstract. Previous studies suggested that certain plants, such as guarana (Paullinia cupana), exert a protective effect against cancer-related fatigue in breast cancer patients undergoing chemotherapy. However, guarana possesses bioactive molecules, such as caffeine and catechin, which may affect the pharmacological properties of antitumor drugs. Therefore, the aim of this study was to evaluate the effects of guarana on breast cancer cell response to 7 chemotherapeutic agents currently used in the treatment of breast cancer. To perform this study, MCF-7 breast cancer cells were cultured under controlled conditions and exposed to 1, 5 and 10 µg/ml guarana concentrations, with and without chemotherapeutics (gemcitabine, vinorelbine, methotrexate, 5-fluorouracil, paclitaxel, doxorubicin and cyclophosphamide). The effect of these treatments on MCF-7 cell viability and proliferation was spectrophotometrically analyzed with the MTT assay. The main results demonstrated an antiproliferative effect of guarana at concentrations of 5 and 10 µg/ml and a significant effect on chemotherapeutic drug action. In general, guarana improved the antiproliferative effect of chemotherapeutic agents, causing a decrease of >40% in cell growth after 72 h of exposure. The results suggested an interaction of guarana with the chemotherapeutic drugs, which requires confirmation by in vivo complementary studies.

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Section: Discussionmentioning

confidence: 99%

Effect of Paullinia cupana on MCF-7 breast cancer cell response to chemotherapeutic drugs

Hertz

Cadoná

Machado

et al. 2014

Molecular and Clinical Oncology

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“…7 The inhibitory effect of EGCG on Nrf2 siRNA transfected MCF-7/TAM cell proliferation. Cells were treated with various concentrations of EGCG 24 h, and cell viability was determined by the MTT assay involved in the mechanism of drug resistance in MCF-7 cells [52]. These prompted us to determine whether EGCG in combination with Nrf2 siRNA exerts a synergic pro-apoptotic effect that are greater than those of each agent taken individually and can sensitize cancer cells to anticancer drugs through inhibiting Nrf2 signaling pathway.…”

Section: Discussionmentioning

confidence: 99%

Combination of siRNA-directed gene silencing with epigallocatechin-3-gallate (EGCG) reverses drug resistance in human breast cancer cells

Esmaeili

2015

J Chem Biol

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Elevated expression of NF-E2-related factor 2 (Nrf2), a nuclear transcription factor, is a frequent genetic abnormality seen in this malignancy and is an important contributor to chemoresistance in cancer therapy. In the present study, we investigated if Nrf2 was associated with drug resistance in tamoxifen-resistant MCF-7 (MCF-7/TAM) cells, and whether EGCG, major flavonoid isolated from green tea, could reverse drug resistance in MCF-7/TAM cells. Our results showed that the endogenous expression of Nrf2 as well as its target proteins heme oxygenase-1, NADP (H):quinone oxidoreductase in MCF-7/TAM cells was higher than that in MCF-7 cells. Epicatechin gallate (EGCG) significantly sensitizes MCF-7/TAM cells to tamoxifen and dramatically reduced Nrf2 expression at both the messenger RNA and protein, leading to a reduction of Nrf2-downstream genes. In addition, using siRNA technique, we found that the intracellular Nrf2 protein level was significantly decreased in MCF-7/ TAM cells and tamoxifen resistance was partially reversed by Nrf2 siRNA. Combination of siRNA-directed gene silencing with EGCG downregulated the Nrf2-dependent response and partly reversed tamoxifen resistance in MCF-7/TAM cells in a synergic manner. These results suggested that combining the chemotherapeutic effect of EGCG with siRNA-mediated Nrf2 knock-down results in the feasibility of using Nrf2 inhibitors to increase efficacy of chemotherapeutic drugs.

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“…Some recent studies have described this effect for 5-FU, 5 doxorubicin (DOX), 6,7 or tamoxifen. 8 To explain EGCG-induced increased intracellular drug concentration, different mechanisms have been suggested. Modulation of dihydropyrimidine dehydrogenase (DPD), a rate-limiting enzyme in the elimination of 5-FU, has been recently proposed as underlying event for the significantly increased 5-FU plasma concentration in rats treated with 5-FU and EGCG.…”

Section: Alteration Of Anticancer Drug Pharmacokineticsmentioning

confidence: 99%

“…As previously described, this catechin has been shown to act as chemosensitizer for DOX and tamoxifen in chemoresistant hepatocellular and breast cancer models, through decreased P-gP efflux pump activity and reduced expression of proteins involved in drug resistance such as MDR-1 and BCRP. 7,8 Expression of GRP78, which is over-expressed in chemoresistant cancer cells, has been shown to be decreased after drug-EGCG co-treatment, and has been proposed to mediate EGCG-induced sensitization of glioblastoma cells to temozolomide, 15 and breast cancer cells to paclitaxel. 16 In both cases, increased apoptosis and reduced tumor growth were described as a consequence of the co-treatment.…”

Section: Modulation Of Chemoresistance-related Proteinsmentioning

confidence: 99%

Green tea polyphenol epigallocatechin-3-gallate (EGCG) as adjuvant in cancer therapy

et al. 2013

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s u m m a r yBackground & aims: Green tea catechins, especially epigallocatechin-3-gallate (EGCG), have been associated with cancer prevention and treatment. This has resulted in an increased number of studies evaluating the effects derived from the use of this compound in combination with chemo/radiotherapy. This review aims at compiling latest literature on this subject. Methods: Keywords including EGCG, cancer, chemotherapy, radiotherapy and side effects, were searched using PubMed and ScienceDirect databases to identify, analyze, and summarize the research literature on this topic. Most of the studies on this subject up to date are preclinical. Relevance of the findings, impact factor, and date of publication were critical parameters for the studies to be included in the review. Results: Additive and synergistic effects of EGCG when combined with conventional cancer therapies have been proposed, and its anti-inflammatory and antioxidant activities have been related to amelioration of cancer therapy side effects. However, antagonistic interactions with certain anticancer drugs might limit its clinical use. Conclusions: The use of EGCG could enhance the effect of conventional cancer therapies through additive or synergistic effects as well as through amelioration of deleterious side effects. Further research, especially at the clinical level, is needed to ascertain the potential role of EGCG as adjuvant in cancer therapy.

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(-)-Epigallocatechin-3-gallate downregulates Pg-P and BCRP in a tamoxifen resistant MCF-7 cell line

Cited by 109 publications

References 31 publications

Effect of Paullinia cupana on MCF-7 breast cancer cell response to chemotherapeutic drugs

Effect of Paullinia cupana on MCF-7 breast cancer cell response to chemotherapeutic drugs

Combination of siRNA-directed gene silencing with epigallocatechin-3-gallate (EGCG) reverses drug resistance in human breast cancer cells

Green tea polyphenol epigallocatechin-3-gallate (EGCG) as adjuvant in cancer therapy

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