title: Chemoprevention of rat mammary carcinogenesis by spirulina.
abstract: Spirulina (SP) (Arthrospira platensis; previously Spirulina platensis) is a filamentous blue-green microalga (cyanobacterium) with potent dietary phytoantioxidant and anticancerous properties. We investigated the chemopreventive effect of SP against 7,12-dimethylbenz[a]anthracene (DMBA)-induced rat breast carcinogenesis, and further studied its underlying mechanisms of action in vitro. Remarkably, SP cleared DMBA-induced rat mammary tumors, which was clearly confirmed by morphological and histological methods. SP supplementation reduced the incidence of breast tumors from 87% to 13%. At the molecular level, immunohistochemical analysis revealed that SP supplementation reduced expression of both Ki-67 and estrogen α. More interestingly, molecular analysis in the in vitro experiments indicated that SP treatment inhibited cell proliferation by 24 hours, which was accompanied by increased p53 expression, followed by increased expression of its downstream target gene, Cdkn1a (alias p21 or p21(Waf1/Cip1)). In addition, SP increased Bax and decreased Bcl-2 expression, indicating induction of apoptosis by 48 hours after SP treatment. To our knowledge, this is the first report of in vivo chemopreventive effect of SP against DMBA-induced breast carcinogenesis in rat, supporting its potential use in chemoprevention of cancer.
authors.affiliation: Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman. Electronic address: aouhtit@squ.edu.om.
authors.forename: Allal
authors.initials: A
authors.lastname: Ouhtit
authors.affiliation: Department of Zoology, Faculty of Science, Mansoura University, Mansoura, Egypt.
authors.forename: Mohammed F
authors.initials: MF
authors.lastname: Ismail
authors.affiliation: Department of Zoology, Faculty of Science, Mansoura University, Mansoura, Egypt.
authors.forename: Amira
authors.initials: A
authors.lastname: Othman
authors.affiliation: Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman.
authors.forename: Augusta
authors.initials: A
authors.lastname: Fernando
authors.affiliation: Department of Zoology, Faculty of Science, Mansoura University, Mansoura, Egypt.
authors.forename: Mohamed E
authors.initials: ME
authors.lastname: Abdraboh
authors.affiliation: Department of Family Medicine and Public Health, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman.
authors.forename: Attalla F
authors.initials: AF
authors.lastname: El-Kott
authors.affiliation: Department of Botany, Faculty of Science, Mansoura University, Mansoura, Egypt.
authors.forename: Yahia A
authors.initials: YA
authors.lastname: Azab
authors.affiliation: Department of Zoology, Faculty of Science, Mansoura University, Mansoura, Egypt.
authors.forename: Sherif H
authors.initials: SH
authors.lastname: Abdeen
authors.affiliation: Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman.
authors.forename: Rajiv L
authors.initials: RL
authors.lastname: Gaur
authors.affiliation: Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman.
authors.forename: Ishita
authors.initials: I
authors.lastname: Gupta
authors.affiliation: Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman.
authors.forename: Somya
authors.initials: S
authors.lastname: Shanmuganathan
authors.affiliation: Department of Family Medicine and Public Health, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman.
authors.forename: Yahya M
authors.initials: YM
authors.lastname: Al-Farsi
authors.affiliation: Department of Genetics, College of Medicine and Health Sciences, Sultan Qaboos University, Muscat, Sultanate of Oman.
authors.forename: Hamad
authors.initials: H
authors.lastname: Al-Riyami
authors.affiliation: Department of Obstetrics and Gynecology, Stanley S. Scott Cancer; Louisiana State University Health Science Center, New Orleans, Louisiana.
authors.forename: Madhwa H G
authors.initials: MH
authors.lastname: Raj
mesh_terms: D000818:Animals; D015153:Blotting, Western; D018890:Chemoprevention / Q000379:methods*; D005260:Female; D015870:Gene Expression; D006801:Humans; D007150:Immunohistochemistry; D061986:MCF-7 Cells; D008325:Mammary Neoplasms, Experimental / Q000517:prevention & control*; D051381:Rats; D017207:Rats, Sprague-Dawley; D053545:Spirulina