Oldenlandia diffusa extracts exert antiproliferative and apoptotic effects on human breast cancer cells through ERα/Sp1-mediated p53 activation.
Breast cancer is the most frequent tumor and a major cause of death among women. Estrogens play a crucial role in breast tumor growth, which is the rationale for the use of hormonal antiestrogen therapies. Unfortunately, not all therapeutic modalities are efficacious and it is imperative to develop new effective antitumoral drugs. Oldenlandia diffusa (OD) is a well-known medicinal plant used to prevent and treat many disorders, especially cancers. The aim of this study was to investigate the effects of OD extracts on breast cancer cell proliferation. We observed that OD extracts strongly inhibited anchorage-dependent and -independent cell growth and induced apoptosis in estrogen receptor alpha (ERα)-positive breast cancer cells, whereas proliferation and apoptotic responses of MCF-10A normal breast epithelial cells were unaffected. Mechanistically, OD extracts enhance the tumor suppressor p53 expression as a result of an increased binding of ERα/Sp1 complex to the p53 promoter region. Finally, we isolated ursolic and oleanolic acids as the bioactive compounds able to upregulate p53 expression and inhibit breast cancer cell growth. These acids were greatly effective in reducing tamoxifen-resistant growth of a derivative MCF-7 breast cancer cell line resistant to the antiestrogen treatment. Our results evidence how OD, and its bioactive compounds, exert antiproliferative and apoptotic effects selectively in ERα-positive breast cancer cells, highlighting the potential use of these herbal extracts as breast cancer preventive and/or therapeutic agents.
Lester and Sue Smith Breast Center and Department of Molecular and Cellular Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX, USA.
Guowei
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Gu
Ines
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Barone
Luca
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Gelsomino
Cinzia
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Giordano
Daniela
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Bonofiglio
Giancarlo
G
Statti
Francesco
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Menichini
Stefania
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Catalano
Sebastiano
S
Andò
D017209:Apoptosis / Q000187:drug effects*; D001943:Breast Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D050759:Cyclin-Dependent Kinase Inhibitor p21 / Q000235:genetics / Q000378:metabolism; D019008:Drug Resistance, Neoplasm / Q000187:drug effects / Q000235:genetics; D020847:Estrogen Receptor Modulators / Q000494:pharmacology; D047628:Estrogen Receptor alpha / Q000235:genetics* / Q000378:metabolism; D004967:Estrogens / Q000378:metabolism; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D006801:Humans; D007136:Immunoglobulins / Q000235:genetics* / Q000378:metabolism; D032067:Oldenlandia / Q000737:chemistry*; D009828:Oleanolic Acid / Q000494:pharmacology; D010936:Plant Extracts / Q000494:pharmacology*; D011401:Promoter Regions, Genetic / Q000187:drug effects; D013629:Tamoxifen / Q000494:pharmacology; D015533:Transcriptional Activation / Q000187:drug effects / Q000235:genetics; D014315:Triterpenes / Q000494:pharmacology; D016159:Tumor Suppressor Protein p53 / Q000235:genetics* / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects; D000097245:Ursolic Acid
D050759:Cyclin-Dependent Kinase Inhibitor p21; D020847:Estrogen Receptor Modulators; D047628:Estrogen Receptor alpha; D004967:Estrogens; D007136:Immunoglobulins; D009828:Oleanolic Acid; D010936:Plant Extracts; D013629:Tamoxifen; D014315:Triterpenes; D016159:Tumor Suppressor Protein p53; D000097245:Ursolic Acid; C506487:ESR1 protein, human; C090698:SP1 antigen; C495901:TP53 protein, human