phytoestrogens and Neoplasm-Metastasis

Genistein being a phytoestrogen imitates the characteristics of estrogen, which can be useful to treat conditions by reducing the estrogen levels at the time of menopause, osteoporosis and high risk for breast cancer.. The superior binding of genistein to ERβ might help in reducing breast malignancy risk.. Genistein induces cell cycle arrest, anti-metastatic properties and ultimately affects the breast cancer cell growth by multiple mechanisms. Genistein-mediated anti-proliferative or anti-growth effects are usually observed at higher concentrations. These signaling pathways involve the decrease of NF-κB, HIF-1α, VEGF, and an increase of tumor suppressor p21. This will provide further insight into understanding the biology of transcription factors NF-κB, and HIF-1α in breast cancer.

Topics: Breast Neoplasms; Cell Cycle Checkpoints; Cell Proliferation; Estrogen Receptor beta; Female; Genistein; Humans; Neoplasm Metastasis; Phytoestrogens; Signal Transduction

Epithelial-mesenchymal transition (EMT) plays a key role in tumor progression. The cells undergoing EMT upregulate the expression of cell motility-related proteins and show enhanced migration and invasion. The hallmarks of EMT in cancer cells include changed cell morphology and increased metastatic capabilities in cell migration and invasion. Therefore, prevention of EMT is an important tool for the inhibition of tumor metastasis. A novel preventive therapy is needed, such as treatment of natural dietary substances that are nontoxic to normal human cells, but effective in inhibiting cancer cells. Phytoestrogens, such as genistein, resveratrol, kaempferol and 3,3'-diindolylmethane (DIM), can be raised as possible candidates. They are plant-derived dietary estrogens, which are found in tea, vegetables and fruits, and are known to have various biological efficacies, including chemopreventive activity against cancers. Specifically, these phytoestrogens may induce not only anti-proliferation, apoptosis and cell cycle arrest, but also anti-metastasis by inhibiting the EMT process in various cancer cells. There have been several signaling pathways found to be associated with the induction of the EMT process in cancer cells. Phytoestrogens were demonstrated to have chemopreventive effects on cancer metastasis by inhibiting EMT-associated pathways, such as Notch-1 and TGF-beta signaling. As a result, phytoestrogens can inhibit or reverse the EMT process by upregulating the expression of epithelial phenotypes, including E-cadherin, and downregulating the expression of mesenchymal phenotypes, including N-cadherin, Snail, Slug, and vimentin. In this review, we focused on the important roles of phytoestrogens in inhibiting EMT in many types of cancer and suggested phytoestrogens as prominent alternative compounds to chemotherapy.

Topics: Anticarcinogenic Agents; Antineoplastic Agents; Cell Line, Tumor; Epithelial-Mesenchymal Transition; Genistein; Humans; Indoles; Kaempferols; Neoplasm Metastasis; Neoplasms; Phytoestrogens; Resveratrol; Stilbenes

Cancer is a leading cause of death worldwide, and the numbers of new cancer cases are expected to continue to rise. The main goals of cancer therapy include removing the primary tumor, preventing the spread of distant metastases, and improving survival and quality of life for the patients. To attain these goals of cancer therapy, the combination of different chemotherapeutics, as opposed to the conventional single-agent treatment, is an emerging area of research. Given the potential risks of drug toxicity in such treatment, the focus is to have a second compound that increases the anticancer potential of the primary agent but which reduces toxicity. There is an ever growing interest in treatment with natural compounds, such as plant phytoestrogens, as an adjuvant cancer therapy along with conventional cancer therapy. The question remains whether or not adding these compounds to the cancer therapy regimen as a second agent would be beneficial, and if they are safe to be used among cancer patients. The current literature suggests that phytoestrogen treatment is capable of inducing G2/M cell cycle arrest in a number of cancer cell lines, as well as upregulating cell cycle inhibitory molecules. Phytoestrogen therapy has been shown to inhibit inflammation, angiogenesis and metastases in various IN VIVO tumor models, and pronounced benefits have been observed when combined with radiation therapy. The lack of side effects from phase I and II clinical trials of phytoestrogens in cancer therapy points towards their safety, but to further understand their added benefit clinical studies with large sample sizes are required. We have reviewed the recent research studies in these areas in an attempt to find evidence for their role in cancer therapy as well as safety.

Topics: Animals; Antineoplastic Agents, Phytogenic; Cell Cycle; Chemotherapy, Adjuvant; Humans; Inflammation; Isoflavones; Lignans; Mice; Neoplasm Metastasis; Neoplasms; Neovascularization, Pathologic; Phytoestrogens; Randomized Controlled Trials as Topic

Arctigenin is a plant lignan extracted from Arctium lappa that has been shown to have estrogenic properties. In spite of the health benefits of phytoestrogens reducing the risk of osteoporosis, heart disease, and menopausal symptoms, its benefits against the risk of breast cancer have not been fully elucidated. Thus, we investigated the effects of arctigenin on metastasis of breast cancer using both estrogen receptor (ER)-positive MCF-7 and ER-negative MDA-MB-231 human breast cancer cell lines to see if the effects are dependent on the status of ER expression. In ER-positive MCF-7 cells, arctigenin efficiently inhibited 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced cell migration and invasion. The activity of crucial metastatic protease matrix metalloprotease (MMP)-9 in gelatin zymography was also efficiently decreased by arctigenin, as well as its mRNA expression. Notably, arctigenin exhibited similar anti-metastatic effects even in ER-negative MDA-MB-231 cells, suggesting that the anti-metastatic effects of arctigenin were not exerted via the ER. The upstream signaling pathways involved in the regulation of MMP-9 and urokinase plasminogen activator (uPA) were analyzed using western blotting. The activation of Akt, NF-κB and MAPK (ERK 1/2 and JNK 1/2) was found to be inhibited. Taken together, these data suggest that arctigenin confers anti-metastatic effects by inhibiting MMP-9 and uPA via the Akt, NF-κB and MAPK signaling pathways on breast cancer, regardless of ER expression. Therefore, we propose that the intake of arctigenin could be an effective supplement for breast cancer patients.

Topics: Breast Neoplasms; Cell Line, Tumor; Cell Movement; Female; Furans; Gene Expression; Gene Expression Regulation, Neoplastic; Humans; Lignans; Matrix Metalloproteinase 9; MCF-7 Cells; Neoplasm Metastasis; Phytoestrogens; Receptors, Estrogen; Signal Transduction; Urokinase-Type Plasminogen Activator