PTPRJ is a receptor‐like protein tyrosine phosphatase mainly known for its antiproliferative and tumor‐suppressive functions. PTPRJ dephosphorylates several growth factors and their receptors, negatively regulating cell proliferation and migration. We recently identified a disulfide‐bridged nonapeptide, named PTPRJ‐19 (H‐[Cys‐His‐His‐Asn‐Leu‐Thr‐His‐Ala‐Cys]‐OH), which activates PTPRJ, thereby causing cell growth inhibition and apoptosis of both cancer and endothelial cells. With the aim of replacing the disulfide bridge by a chemically more stable moiety, we have synthesized and tested a series of lactam analogues of PTPRJ‐19. This replacement led to analogues with higher activity and greater stability than the parent peptide.

中文翻译：

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内酰胺限制的PTPRJ激动剂肽的设计，合成，生物学活性和结构分析

PTPRJ是一种受体样蛋白酪氨酸磷酸酶，主要以其抗增殖和抑制肿瘤的功能而著称。PTPRJ使多种生长因子及其受体脱磷酸化，从而负面调节细胞的增殖和迁移。我们最近发现了一种二硫键桥接的九肽，称为PTPRJ-19（H- [Cys-His-His-Asn-Leu-Thr-His-Ala-Cys] -OH），它可以激活PTPRJ，从而引起细胞生长抑制和凋亡癌细胞和内皮细胞。为了用化学上更稳定的部分取代二硫键，我们合成并测试了PTPRJ-19的一系列内酰胺类似物。这种替代导致比亲本肽具有更高活性和更高稳定性的类似物。