Department of Biochemistry and Molecular Biology, School of Medicine, Kyung Hee University, Seoul 02447, Republic of Korea.
Department of Oriental Pharmaceutical Science, College of Pharmacy, Kyung Hee University, Seoul 02447, Republic of Korea.
J Microbiol Biotechnol. 2021 Apr 28;31(4):540-549. doi: 10.4014/jmb.2012.12015.
The Wnt/β-catenin signaling pathway is involved in breast cancer and KYC4048 is a myxobacterial strain that can produce a variety of bioactive secondary metabolites. Although a previous study revealed that KYC4048 metabolites exhibit anti-proliferative effects on breast cancer, the biochemical mechanism involved in their effects remains unclear. In the present study, KYC4048 metabolites were separated into polar and non-polar (ethyl acetate and n-hexane) fractions via liquid-liquid extraction. The effects of these polar and non-polar KYC4048 metabolites on the viability of breast cancer cells were then determined by MTT assay. Expression levels of Wnt/β-catenin pathway proteins were determined by Western blot analysis. Cell cycle and apoptosis were measured via fluorescence-activated cell sorting (FACS). The results revealed that non-polar KYC4048 metabolites induced cell death of breast cancer cells and decreased expression levels of WNT2B, β-catenin, and Wnt target genes (c-Myc and cyclin D1). Moreover, the -hexane fraction of non-polar KYC4048 metabolites was found most effective in inducing apoptosis, necrosis, and cell cycle arrest, leading us to conclude that it can induce apoptosis of breast cancer cells through the Wnt/β-catenin pathway. These findings provide evidence that the -hexane fraction of non-polar KYC4048 metabolites can be developed as a potential therapeutic agent for breast cancer via inhibition of the Wnt/β-catenin pathway.
Wnt/β-连环蛋白信号通路参与乳腺癌的发生，KYC4048 是一种粘细菌菌株，能够产生多种生物活性的次级代谢产物。尽管先前的研究表明 KYC4048 代谢产物对乳腺癌具有抗增殖作用，但它们作用的生化机制尚不清楚。在本研究中，通过液液萃取将 KYC4048 代谢产物分离为极性和非极性（乙酸乙酯和正己烷）部分。然后通过 MTT 测定法确定这些极性和非极性 KYC4048 代谢产物对乳腺癌细胞活力的影响。通过 Western blot 分析测定 Wnt/β-连环蛋白通路蛋白的表达水平。通过荧光激活细胞分选（FACS）测量细胞周期和凋亡。结果表明，非极性 KYC4048 代谢产物诱导乳腺癌细胞死亡，并降低 WNT2B、β-连环蛋白和 Wnt 靶基因（c-Myc 和 cyclin D1）的表达水平。此外，非极性 KYC4048 代谢产物的正己烷部分最有效地诱导细胞凋亡、坏死和细胞周期停滞，这表明它可以通过 Wnt/β-连环蛋白通路诱导乳腺癌细胞凋亡。这些发现为非极性 KYC4048 代谢产物的正己烷部分通过抑制 Wnt/β-连环蛋白通路可以开发为治疗乳腺癌的潜在治疗剂提供了证据。
