National Glycoengineering Research Center, NMPA Key Laboratory for Quality Research and Evaluation of Carbohydrate- based Medicine, Shandong University, Qingdao, Shandong, 266237, China.
Curr Protein Pept Sci. 2024;25(6):480-491. doi: 10.2174/0113892037287189240122110819.
It has been proven that vasoactive intestinal peptide (VIP) was involved in the pathogenesis of prostate cancer. Cardin . found that by an alanine scan, the heparin- binding site on VIP was exactly the same sequence in VIP and its receptor. Therefore, heparin could competitively block the binding of VIP and its receptor. However, the structure-activity relationship between heparin and VIP has not been reported, especially in terms of the sequence and sulfation patterns of heparin oligosaccharides upon binding to VIP.
A variety of experiments were designed to study the binding process and structure-activity relationship between heparin oligosaccharides and VIP.
Heparin was enzymatically digested and purified to produce heparin oligosaccharides, and the structures were characterized by NMR. The binding capacity between heparin oligosaccharides and VIP was analyzed by GMSA and ITC experiments. The binding between heparin oligosaccharides and VIP was simulated using a molecular docking program to show the complex. ELISA assay was used to investigate the effect of non-anticoagulant heparin oligosaccharides on the VIP-mediated cAMP/PKA signaling pathway .
The results indicated that both the length and the sulfation pattern of heparin oligosaccharides affected its binding to VIP. VIP could induce the expression of cAMP at a higher level in PC3 cells, which could be regulated by the interaction of heparin oligosaccharides and VIP.
The binding between heparin oligosaccharides and VIP could block the binding between VIP and its receptor on tumor cells. Downloading the regulation of the expression level of cAMP could possibly further affect the subsequent activation of PKA. These non-anticoagulant heparin oligosaccharides may block the VIP-mediated cAMP/PKA signaling pathway and thus exert their antitumor activity.
已有研究证明血管活性肠肽（VIP）参与了前列腺癌的发病机制。Cardin 发现，通过丙氨酸扫描，VIP 上的肝素结合位点与 VIP 和其受体完全相同。因此，肝素可以竞争性地阻断 VIP 与其受体的结合。然而，肝素与 VIP 之间的结构-活性关系尚未被报道，特别是肝素寡糖与 VIP 结合时的序列和硫酸化模式。
设计了多种实验来研究肝素寡糖与 VIP 之间的结合过程和结构-活性关系。
通过酶解和纯化肝素制备肝素寡糖，并通过 NMR 对其结构进行表征。通过 GMSA 和 ITC 实验分析肝素寡糖与 VIP 之间的结合能力。使用分子对接程序模拟肝素寡糖与 VIP 之间的结合，以显示复合物。ELISA 检测非抗凝肝素寡糖对 VIP 介导的 cAMP/PKA 信号通路的影响。
结果表明，肝素寡糖的长度和硫酸化模式都影响其与 VIP 的结合。VIP 可在 PC3 细胞中诱导 cAMP 更高水平的表达，而肝素寡糖与 VIP 的相互作用可以调节这种表达。
肝素寡糖与 VIP 的结合可以阻断 VIP 与其在肿瘤细胞上的受体的结合。下调 cAMP 的表达水平可能会进一步影响随后 PKA 的激活。这些非抗凝肝素寡糖可能通过阻断 VIP 介导的 cAMP/PKA 信号通路发挥其抗肿瘤活性。
