Sadegh Rajabi1, Maryam Shojaee2, Ali Malmir3, Mostafa Rezaei Tavirani4, Shokoofe Noori1. 1. Department of clinical Biochemistry, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran. 2. Department of Biology, Payame Noor University of Mashhad, Mashhad, Iran. 3. Department of Cellular and Molecular Biology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University G.C, Tehran, Iran. 4. Proteomics Research Center, Faculty of Paramedical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
Abstract
PURPOSE: Cancer stem cells (CSCs) play an important role in various stages of cancer development and therapy refractoriness. 8-Hydroxydaidzein (8-OHD) has revealed anti-cancer activity in different tumors. Accordingly, we aimed to assess the effects of 8-OHD on the suppression of breast cancer stem-like cells (BCSCs). METHODS: The anti-proliferative and pro-apoptotic properties of 8-OHD were examined by MTS assay and flowcytometry. The expression levels of stemness markers and JAK2/STAT proteins were measured by quantitative real time-PCR (qRT-PCR) and western blotting, respectively. RESULTS: 8-OHD significantly decreased three out of six stemness markers and remarkably reduced viability and induced apoptosis of spheroidal and parental cells compared to controls. Further experiments using CD95L, as a death ligand, and ZB4 antibody, as an extrinsic apoptotic pathway blocker, showed that 8-OHD induced apoptosis through the intrinsic pathway, proposing a mechanism by which 8-OHD triggers apoptosis. Results of western blot analysis also revealed a marked decline in the phosphorylation of JAK2 and STAT proteins. CONCLUSION: Our study, for the first time, elucidated an anti-BCSC activity for 8-OHD via decreasing stemness markers, inducing toxicity and stimulating apoptosis in these cells and parental cells. Our results also suggested a novel mechanism by which 8-OHD induces apoptosis in BCSCs.
PURPOSE:Cancer stem cells (CSCs) play an important role in various stages of cancer development and therapy refractoriness. 8-Hydroxydaidzein (8-OHD) has revealed anti-cancer activity in different tumors. Accordingly, we aimed to assess the effects of 8-OHD on the suppression of breast cancer stem-like cells (BCSCs). METHODS: The anti-proliferative and pro-apoptotic properties of 8-OHD were examined by MTS assay and flowcytometry. The expression levels of stemness markers and JAK2/STAT proteins were measured by quantitative real time-PCR (qRT-PCR) and western blotting, respectively. RESULTS:8-OHD significantly decreased three out of six stemness markers and remarkably reduced viability and induced apoptosis of spheroidal and parental cells compared to controls. Further experiments using CD95L, as a death ligand, and ZB4 antibody, as an extrinsic apoptotic pathway blocker, showed that 8-OHD induced apoptosis through the intrinsic pathway, proposing a mechanism by which 8-OHD triggers apoptosis. Results of western blot analysis also revealed a marked decline in the phosphorylation of JAK2 and STAT proteins. CONCLUSION: Our study, for the first time, elucidated an anti-BCSC activity for 8-OHD via decreasing stemness markers, inducing toxicity and stimulating apoptosis in these cells and parental cells. Our results also suggested a novel mechanism by which 8-OHD induces apoptosis in BCSCs.