Laminaria japonica is consumed as a health food and used as a traditional medicine because of its biochemical and pharmacological abilities. However, the anti-tumor effect of L. japonica peptides has not been well explored. In the current study, three novel L. japonica cyclic peptides (LCPs) were isolated using an anti-cancer activity tracking method. LCP-3 [cyclo-(Trp-Leu-His-Val)] significantly induced apoptosis in Caco-2 cells in vitro. LCP-3 increased the Bax/Bcl-2 ratio, activated caspases, and regulated the p53/murine double minute 2 network. LCP-3 blocked Caco-2 cells in G0/G1 phase, which was accompanied by the inhibition of cyclin expression. Furthermore, LCP-3 inhibited colon cancer growth and induced cancer cell apoptosis in tumor-bearing mice. Notably, LCP-3 might be a potential agent for the prevention of colon cancer.

中文翻译：

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海带环肽通过体外和体内凋亡诱导发挥抗结直肠癌作用

海带因其生化和药理能力而被用作保健食品和传统药物。然而， L. japonica肽的抗肿瘤作用尚未得到很好的探索。在目前的研究中，使用抗癌活性追踪方法分离了三种新型L. japonica环肽 (LCP)。LCP-3 [cyclo-(Trp-Leu-His-Val)]在体外显着诱导 Caco-2 细胞凋亡. LCP-3 增加了 Bax/Bcl-2 比率，激活了半胱天冬酶，并调节了 p53/鼠双分钟 2 网络。LCP-3在G0/G1期阻断Caco-2细胞，同时抑制cyclin表达。此外，LCP-3 在荷瘤小鼠中抑制结肠癌生长并诱导癌细胞凋亡。值得注意的是，LCP-3 可能是预防结肠癌的潜在药物。