Mechanisms of Fucoxanthin from Sargassum fusiforme in Inhibiting Proliferation of Human Acute Leukemia REH Cells

Background: Fucoxanthin, a carotenoid predominantly found in brown algae, exhibits notable anti-tumor activity. However, its mechanisms underlying the inhibition of leukemia cell proliferation remain poorly understood. Here, we explored the effect of Sargassum fusiforme fucoxanthin (SFFx) on the proliferation of human acute non-B non-T lymphocytic leukemia REH cells and its underlying mechanism. Methods: The MTT assay was used to assess the impact of SFFx on REH cell viability. EdU assay, TUNEL assay, and propidium iodide (PI) staining were employed to evaluate cell proliferation, DNA damage, and cell cycle distribution, respectively. Intracellular reactive oxygen species (ROS) levels and mitochondrial membrane potential (MMP) were measured using DCFH-DA fluorescent probe and JC-1 staining, respectively. The expression levels of Cyclin E1, Cyclin-Dependent Kinase 1 (CDK1), CDK2, CDK4, and TP53 in REH cells were detected by qRT-PCR and Western blot. Results: SFFx inhibited REH cell viability in a concentration- and time-dependent manner (P<0.01). SFFx significantly increased intracellular ROS levels and decreased MMP (P<0.01). Furthermore, SFFx induced G1 phase cell cycle arrest in REH cells, significantly upregulating the expression of the cell cycle-related gene TP53 and its protein p53 (P<0.01), while downregulating the expression of CCNE1, CDK1, CDK2, CDK4 genes and their corresponding proteins Cyclin E1, CDK1, CDK2, and CDK4 (P<0.01). Conclusion: Fucoxanthin from Sargassum fusiforme inhibits REH cell proliferation by inducing cell cycle arrest, this study provides theoretical support for the development and utilization of Sargassum fusiforme resources and the research of anti-leukemia drugs.