title: The phytoestrogenic Cyclopia extract, SM6Met, increases median tumor free survival and reduces tumor mass and volume in chemically induced rat mammary gland carcinogenesis.
abstract: SM6Met, a phytoestrogenic extract of Cyclopia subternata indigenous to the Western Cape province of South Africa, displays estrogenic attributes with potential for breast cancer chemoprevention. In this study, we report that SM6Met, in the presence of estradiol, induces a significant cell cycle G0/G1 phase arrest similar to the selective estrogen receptor modulator, tamoxifen. Furthermore, as a proof of concept, in the N-Methyl-N-nitrosourea induced rat mammary gland carcinogenesis model, SM6Met increases tumor latency by 7days and median tumor free survival by 42 days, while decreasing palpable tumor frequency by 32%, tumor mass by 40%, and tumor volume by 53%. Therefore, the current study provides proof of concept that SM6Met has definite potential as a chemopreventative agent against the development and progression of breast cancer.
authors.affiliation: Biochemistry Department, Stellenbosch University, Stellenbosch, Western Cape, South Africa.
authors.forename: Koch
authors.initials: K
authors.lastname: Visser
authors.affiliation: Molecular Cell Physiology and Endocrinology, Institute for Zoology, Technische Universität Dresden, Dresden, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Zierau
authors.affiliation: Institute of Experimental Endocrinology, Slovak Academy of Sciences, Bratislava, Slovak Republic.
authors.forename: Dana
authors.initials: D
authors.lastname: Macejová
authors.affiliation: Institute for Pathology, Radeberg, Germany; Institute for Pathology, University Clinic Carl-Gustav-Carus, Dresden, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Goerl
authors.affiliation: Institute for Pathology, University Clinic Carl-Gustav-Carus, Dresden, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Muders
authors.affiliation: Institute for Pathology, University Clinic Carl-Gustav-Carus, Dresden, Germany.
authors.forename: Gustavo B
authors.initials: GB
authors.lastname: Baretton
authors.affiliation: Molecular Cell Physiology and Endocrinology, Institute for Zoology, Technische Universität Dresden, Dresden, Germany.
authors.forename: Günter
authors.initials: G
authors.lastname: Vollmer
authors.affiliation: Biochemistry Department, Stellenbosch University, Stellenbosch, Western Cape, South Africa. Electronic address: al@sun.ac.za.
authors.forename: Ann
authors.initials: A
authors.lastname: Louw
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000302:isolation & purification / Q000494:pharmacology*; D045744:Cell Line, Tumor; D053998:Cyclopia Plant / Q000737:chemistry*; D004965:Estrogen Antagonists / Q000494:pharmacology; D005260:Female; D059585:G1 Phase Cell Cycle Checkpoints / Q000187:drug effects / Q000235:genetics; D006801:Humans; D008321:Mammary Glands, Animal / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008325:Mammary Neoplasms, Experimental / Q000139:chemically induced / Q000188:drug therapy* / Q000401:mortality / Q000473:pathology; D008770:Methylnitrosourea; D048789:Phytoestrogens / Q000302:isolation & purification / Q000494:pharmacology*; D051381:Rats; D011960:Receptors, Estrogen / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D016019:Survival Analysis; D013629:Tamoxifen / Q000494:pharmacology; D047368:Tumor Burden / Q000187:drug effects
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D004965:Estrogen Antagonists; D048789:Phytoestrogens; D011960:Receptors, Estrogen; D013629:Tamoxifen; D008770:Methylnitrosourea
keywords: Breast cancer; Chemoprevention; Cyclopia; N-Methyl-N-nitrosourea; Phytoestrogens