title: Lycopene and beta-carotene induce cell-cycle arrest and apoptosis in human breast cancer cell lines.
abstract: Lycopene and beta-carotene are carotenoids widely distributed in fruits and vegetables, with potential anticancer activity. Epidemiological trials rarely provide evidence for the mechanisms of action of these compounds, and their biological effects at different times of treatment are still unclear. The aim of the present study was to determine the effect of carotenoids on the cell cycle and cell viability in human breast cancer cell lines. Human breast cell lines were treated with carotenoids (0.5-10 μM) for 48 and 96 h. Cell viability was monitored using the MTT method (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide; thiazolyl blue). The cell cycle was analyzed by flow cytometry, and apoptotic cells were identified by annexin/propidium iodide (PI) biomarkers. Our data showed a significant decrease in the number of viable breast cancer cells on treatment with carotenoids. Carotenoids also promoted cell-cycle arrest followed by decreased cell viability in the majority of cell lines after 96 h, compared to controls. Furthermore, an increase in apoptosis was observed in cell lines when cells were treated with carotenoids. Our findings show the capacity of lycopene and beta-carotene to inhibit cell proliferation, arrest the cell cycle in different phases, and increase apoptosis. These findings indicate that the effect was cell type-dependent and that carotenoids are potential agents for biological interference with cancer.
authors.affiliation: Universidade Federal do Estado do Rio de Janeiro, Escola de Nutrição, Departamento de Tecnologia de Alimentos CEP 22290-240, Rio de Janeiro, RJ, Brazil. atteodoro@gmail.com.
authors.forename: Nathalie Fonseca
authors.initials: NF
authors.lastname: Gloria
authors.forename: Nathalia
authors.initials: N
authors.lastname: Soares
authors.forename: Camila
authors.initials: C
authors.lastname: Brand
authors.forename: Felipe Leite
authors.initials: FL
authors.lastname: Oliveira
authors.forename: Radovan
authors.initials: R
authors.lastname: Borojevic
authors.forename: Anderson Junger
authors.initials: AJ
authors.lastname: Teodoro
mesh_terms: D000230:Adenocarcinoma / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D016588:Anticarcinogenic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D002338:Carotenoids / Q000494:pharmacology*; D059447:Cell Cycle Checkpoints / Q000187:drug effects*; D049109:Cell Proliferation / Q000187:drug effects; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D000077276:Lycopene; D014407:Tumor Cells, Cultured; D014815:Vitamins / Q000494:pharmacology; D019207:beta Carotene / Q000494:pharmacology*
chemical_list: D016588:Anticarcinogenic Agents; D014815:Vitamins; D019207:beta Carotene; D002338:Carotenoids; D000077276:Lycopene
keywords: Lycopene; beta-carotene; bioactive compounds; breast cancer; cell cycle