Benefit of Asian pigmented rice bioactive compound and its implication in breast cancer: a systematic review

Background: Utilizing the bioactive compounds found in pigmented rice might significantly reduce the risk of breast cancer. This study aims to systematically review existing literature on the benefit of Asian pigmented rice bioactive compounds and their implication in breast cancer. Methods: Searches of the literature were conducted in two databases (Scopus and PubMed) for a systematic review. The keywords resulted in a total of 407 articles, consisting of 103 PubMed and 304 Scopus articles. 32 manuscripts were excluded because the article was over 10 years old. After excluding book chapters and non-English languages, we had 278 potential articles to be reviewed. After checking and screening the title and abstract and eliminating duplicate articles, then 66 articles were obtained. After the selection and elimination of the full-text manuscripts, finally 10 of them which met the inclusion criteria. Result: The included studies in this review were entirely based in Asia. The year of publication ranged from 2013 to 2020. Half of included studies used black rice extract, two used red jasmine rice extracts, and three used Korean rice extracts (black, red, dark purple and brown rice). All studies were conducted in vitro and three studies were compared with in vivo tests on female mice. The pigmented rice is mainly black, red, and dark purple rice, and contains a variety of peonidin-3-glucoside, cyanidin-3-glucoside, γ-oryzanol, γ-tocotrienol, proanthocyanidin, cinnamic acid, and anthocyanins that may act as pro-apoptotic, anti-proliferative, and anti-metastasis of the breast cancer cells. Conclusion: Pigmented rice is a beneficial food which possessed bioactive compounds that may have significant potential concerning a breast cancer.