icaritin and Breast-Neoplasms

Breast cancer is one of the most prevalent malignancies and the leading cause of cancer-associated mortality in China. Icaritin (ICT), a prenyl flavonoid derived from the

Topics: AMP-Activated Protein Kinases; Animals; Apoptosis; Autophagy; Breast Neoplasms; Cell Line, Tumor; Female; Flavonoids; Humans; Mice; Stearoyl-CoA Desaturase

We aim to investigate the anticancer effects and mechanisms of icaritin against breast cancer.. Both estrogen receptor (ER) positive breast cancer cells MCF- 7 and ER-negative MDA-MB-231 cells were employed. We examined the effects of icaritin on the proliferation and migration by wound healing assay and transwell assay. Cell apoptosis and cell cycle of MCF-7 and MDA-MB-231 cells were analyzed using Flow cytometry. Cell autophagy of MCF-7 and MDA-MB-231 cells was assessed by western blotting, acridine orange staining and confocal microscopy. We also detected the expression of apoptosis-related genes by western blotting. In addition, an autophagy inhibitor was used to investigate whether cytoprotective autophagy was induced. Meanwhile, an ER inhibitor was utilized to explore whether ER was involved in autophagy.. Icaritin inhibited the proliferation and migration, and induced cell cycle arrest of both MDA-MB-231 and MCF-7 cells. Icaritin significantly induced apoptosis of MDA-MB- 231 cells by activating caspase-3. And icaritin stimulated autophagy in MCF-7 cells, as evidenced by increased LC3II/LC3I, enhanced p62 degradation, the accumulation of endogenous LC3 puncta formation, and the increased autophagy flux. Icaritin induced autophagy through upregulating the phosphorylation of AMPK and ULK1. Chloroquine, an autophagy inhibitor, increased icaritin-induced apoptosis and proliferation inhibition of MCF-7 cells. Meanwhile, tamoxifen, an ER inhibitor, reversed icaritin-induced autophagy and proliferation inhibition of MCF-7 cells.. Our study demonstrated that the antitumor effects of icaritin against breast cancer are related to ER, which suggested that the status of ER should be considered in the clinical application of icaritin.

Topics: Apoptosis; Apoptosis Regulatory Proteins; Autophagy; Breast Neoplasms; Cell Cycle; Cell Proliferation; Female; Flavonoids; Gene Expression Regulation, Neoplastic; Humans; Receptors, Estrogen; Signal Transduction; Tumor Cells, Cultured

Due to their various biological activities that are beneficial to human health and antitumor effect, flavonoid compounds have attracted much attention in recent years. Hydrous icaritin (HICT) was such a flavonoid that can inhibit the growth of breast cancer and cancer stem cells. In order to overcome the insolubility problem, HICT was fabricated into nanorods (NRs) through anti-solvent precipitation in this paper using D-α tocopherol acid polyethylene glycol succinate and sodium oleate as a co-stabilizer meanwhile using the mixture of ethanol and acetone (1:2, v/v) as the organic solvent. The obtained HICT NRs showed an average particle size 222.0 nm with a small polydispersity index value of 0.124 and a high zeta potential of - 49.5 mV. HICT NRs could maintain similar particle size in various physiological medium and could be directly lyophilized without the addition of any cytoprotectants and then reconstituted into a colloidal system of similar size. The resultant HICT NRs had a high drug loading content of 55.6% and released HICT in a steady and constant pattern. MTT assay indicated NRs enhanced HICT's antitumor activity to ninefold against MCF-7 breast carcinoma cells.

Topics: Animals; Antineoplastic Agents, Phytogenic; Breast Neoplasms; Drug Stability; Female; Flavonoids; Humans; Injections, Intravenous; MCF-7 Cells; Mice; Mice, Nude; Nanotubes; Paclitaxel; Particle Size

Epimedium is popularly used in traditional Chinese medicine to treat sexual dysfunction, menstrual irregularity, and osteoporosis. The estrogenic effects of the prenylated flavonoids of Epimedium make it an attractive alternative for hormone replacement therapy. Here, we examined the therapeutic potential of the estrogenic herb extract of Epimedium brevicornum as an alternative to hormone replacement therapy in a breast cancer mouse model. To that end, athymic and ovariectomized female nude mice were subcutaneously injected into the mammary fat pads with MCF-7 breast cancer cells, randomly grouped and fed with soy-free feeds, alone or in combination with ethinyl estradiol or different doses of the estrogenic herb extract of E. brevicornum. Our findings demonstrate that unlike ethinyl estradiol, it did not promote the growth of breast cancer xenograft volume and weight, with the highest dose showing a significant reduction in growth and ERα protein content. Moreover, the extract increased uterine weight at the lowest dose, while higher doses had no effects. Put together, our data shows for the first time that despite the estrogenic activity of E. brevicornum, its action is largely tissue specific and dose-dependent. Our data on E. brevicornum presents in vivo evidence for its selective estrogen receptor modulator effect and warrants exploration of its use as an alternative to hormone replacement therapy in menopausal women.

Topics: Animals; Breast Neoplasms; Dose-Response Relationship, Drug; Epimedium; Estrogen Receptor alpha; Ethinyl Estradiol; Female; Flavonoids; Humans; Medicine, Chinese Traditional; Mice; Mice, Nude; Organ Size; Ovariectomy; Plant Extracts; Selective Estrogen Receptor Modulators; Uterus; Xenograft Model Antitumor Assays

There is concern that ingestion of dietary phytoestrogens may increase risk of estrogen receptor alpha (ERα)-positive breast cancer. The prenylflavone icaritin, a phytoestrogen consumed in East Asian societies for its perceived beneficial effects on bone health, stimulated the growth of breast cancer (MCF-7) cells at low concentrations. Although acting like an estrogenic ligand, icaritin exerted an unexpected suppressive effect on estrogen-stimulated breast cancer cell proliferation and gene expression at higher concentrations. Like estradiol, icaritin could dose-dependently destabilize ERα protein. However, destabilization of ERα by the estradiol/icaritin combination was profound and greater than that observed for either compound alone. Microarray gene expression analyses implicated aryl hydrocarbon receptor (AhR) signaling for this suppressive effect of icaritin. Indeed, icaritin was an AhR agonist that competitively reduced specific binding of a potent AhR agonist and increased expression of the AhR-regulated gene CYP1A1. When AhR was knocked down by small interfering RNA, the suppressive effect of icaritin on estradiol-stimulated breast cancer cell growth and gene expression was abolished, and ERα protein stability was partially restored. Similarly in an athymic nude mouse model, icaritin restricted estradiol-stimulated breast cancer xenograft growth and strongly reduced ERα protein levels. Overall, our data support the feasibility for the development of dual agonists like icaritin, which are estrogenic but yet, through activating AhR-signaling, can destabilize ERα protein to restrict ERα-positive breast cancer cell growth.

Topics: Animals; Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Cytochrome P-450 CYP1A1; Estradiol; Estrogen Receptor alpha; Female; Flavonoids; Gene Expression; Humans; Male; Mice; Mice, Inbred BALB C; Mice, Nude; Proteasome Endopeptidase Complex; Receptors, Aryl Hydrocarbon; RNA, Small Interfering; Transcription, Genetic

Icaritin, a prenylflavonoid derivative from Epimedium Genus, regulates many cellular processes. However, the function and the underlying mechanisms of icaritin in breast cancer cell growth have not been well established. Here, we report that icaritin strongly inhibited the growth of breast cancer MDA-MB-453 and MCF7 cells. At concentrations of 2-3 μM, icaritin induced cell cycle arrest at the G(2)/M phase accompanied by a down-regulation of the expression levels of the G(2)/M regulatory proteins such as cyclinB, cdc2 and cdc25C. Icaritin at concentrations of 4-5 μM, however, induced apoptotic cell death characterized by the accumulation of the annexin V- and propidium iodide-positive cells, cleavage of poly ADP-ribose polymerase (PARP) and down-regulation of the Bcl-2 expression. In addition, icaritin also induced a sustained phosphorylation of extracellular signal-regulated kinase (ERK) in these breast cancer cells. U0126, a specific ERK activation inhibitor, abrogated icaritin-induced G2/M cell cycle arrest and cell apoptosis. Icaritin more potently inhibited growth of the breast cancer stem/progenitor cells compared to anti-estrogen tamoxifen. Our results indicate that icaritin is a potent growth inhibitor for breast cancer cells and provide a rationale for preclinical and clinical evaluations of icaritin for breast cancer therapy.

Topics: Antineoplastic Agents; Apoptosis; Breast Neoplasms; Cell Division; Cell Line, Tumor; Cell Proliferation; Enzyme Activation; Extracellular Signal-Regulated MAP Kinases; Flavonoids; G2 Phase; Humans; Neoplastic Stem Cells; Signal Transduction

To investigate the estrogen-like activities of icariin (ICA), icaritin (ICT) and desmethylicaritin (DICT) and their structure/activity relationships.. ICT was hydrolyzed from ICA by cellulase and then DICT was demethylated from ICT in boron tribromide and dichloromethane system. Estrogen-sensitive MCF-7 cells and T47D cells were co-incubated with different concentrations of test compounds for 6 and 9 d respectively, and the cell proliferation was measured by MTT.. ICT and DICT both markedly enhanced cell proliferation. Compared with estradiol (10.(-9) mol/L), the proliferative effects of 10.-6 mol/L ICT and DICT on MCF-7 cells were 90.0% and 94.0% (P<0.01), respectively, and those of T47D cells were 65.6% and 50.0%. (P<0.01). But this phenomenon was not observed with ICA. Cell proliferation induced by ICT and DICT was completely antagonized by 10.(-7 )mol/L pure estrogen receptor antagonist, ICI182,780.. ICT and DICT possess estrogen-like activity of enhancing proliferation in MCF-7 and T47D cells. However, ICA appears to have no estrogenicity on MCF-7 and T47D cell lines in vitro.

Topics: Breast Neoplasms; Cell Division; Drugs, Chinese Herbal; Flavonoids; Humans; Phytoestrogens; Tumor Cells, Cultured

The aims of the present study were to determine the estrogenic activities of icariin (ICA) and its derivatives and their structure-estrogenic activity relationship. Therefore, icaritin (ICT) and desmethylicaritin (DICT) were derived from ICA. The estrogenic activities of ICA, ICT and DICT were examined by cell proliferation and progestogen receptor mRNA expression of estrogen-receptor-positive MCF-7 cells. Current studies exhibited that ICT and DICT both markedly enhanced the proliferation of MCF-7 cells; as compared to estradiol (100%), their relative proliferative effects (RPE) were 90% and 94%, respectively. Cell proliferation induced by ICT and DICT was completely antagonized by ICI182,780. ICT and DICT increased progestogen receptor (PR) at mRNA levels at 48 h after treatment, although the effects were not as prominent as 17beta-estradiol (E2). Those phenomena were not observed with ICA. Results demonstrate that ICT and DICT (nonconjugated forms) possess estrogen-like activity; however, ICA appears to have no estrogenicity in the MCF-7 cell line model in vitro.

Topics: Breast Neoplasms; Cell Line, Tumor; Cell Proliferation; Drugs, Chinese Herbal; Estrogen Receptor Modulators; Female; Flavonoids; Humans; Receptors, Progesterone; Structure-Activity Relationship; Transcription, Genetic