专肽生物_定制多肽合成服务_多肽合成定制服务_多肽合成厂家_多肽合成公司

一种非常热门的RGD环肽。c(RGDfK) 是一种由5个氨基酸组成的首尾酰胺环肿瘤靶向肽，它通过与细胞表面的 αvβ3 整合素结合，特异性靶向肿瘤微血管和癌细胞。

IC50：对细胞粘附显示出抑制作用，IC50范围为0.1至1 μM。

有一系列可识别并结合三肽序列RGD（精氨酸-甘氨酸-天冬氨酸）的整联蛋白亚型，代表参与细胞粘附最显著的识别基序。其中，cyclo (-RGDfK)已被广泛应用于生物材料涂层以改善细胞粘附性或作为显像剂用于肿瘤治疗。 

体外:整联蛋白αvβ3在许多细胞类型包括内皮细胞、上皮细胞、成纤维细胞、成骨细胞和平滑肌细胞中表达。整联蛋白αvβ3在发生血管生成的内皮细胞中上调，肿瘤血管生成期间在内皮细胞中高表达。据报道, Cyclo (-RGDfK)对αvβ3 /αvβ5具有高亲和力，因此可以促进体外成骨细胞和软骨细胞的细胞粘附。

体内:在兔子体内进行动物研究。据证实,新形成的骨组织与RGD-肽包被的植入物产生直接接触,而无包被的植入物似乎与新形成的骨组织分离。这种分离是由一种可阻断植入物和骨骼之间结合的纤维组织层引起。

临床试验：目前尚未进行临床试验。

一种RGD肿瘤靶向肽，与αvβ3受体结合。c（RGDfK）可以很容易地与荧光标记、螯合剂或载体结合。Palecek等人通过重氮转移将ε-氨基转化为叠氮化物，从而允许通过点击化学进一步官能化。巯基可以通过用S-乙酰硫代乙酸（SATA）酰化c（RGDfK）来引入。

An RGD tumor-targeting peptide, which binds to αvβ3 receptors. c(RGDfK) can be easily conjugated to fluorophore tags, chelators, or carriers. Palecek et al. converted the ε-amino group into the azide by diazo transfer allowing further functionalization by click chemistry. Mercapto groups can be introduced via acylation of c(RGDfK) with S-acetylthioacetic acid (SATA).

Cyclo(Arg-Gly-Asp-D-Phe-Lys) is a synthetic peptide that binds to the integrin receptor on pancreatic cancer cells. It has been shown to be an effective diagnostic tool for pancreatic cancer and other cancers, such as prostate, breast, and lung. Cyclo(Arg-Gly-Asp-D-Phe-Lys) selectively binds to cells with high levels of integrin receptors by using "a heterofunctional approach." This technique is used in the synthesis of peptides because it increases the stability of peptides. Cyclo(Arg-Gly-Asp-D-Phe-Lys) can be used for diagnosis or therapeutic purposes.

Cyclo(Arg-Gly-Asp-D-Phe-Lys) is a small molecule drug that binds to the integrin receptor and blocks the growth of solid tumours. It has been shown to inhibit angiogenesis, especially in choroidal neovascularization in mice. Cyclo(Arg-Gly-Asp-D-Phe-Lys) is a cyclic peptide with biological properties that are similar to those of the natural amino acids found in protein. This drug has been shown to be safe for use in humans and animals, with no observed toxicity or side effects.

靶向多肽可以根据其功能和用途分为不同的类别。在PDC（多肽偶联药物）中，靶向多肽通常被分为细胞穿透肽和细胞靶向肽两大类。

细胞穿透肽：这类多肽能够跨越细胞膜，转运具有生物活性的大分子物质，如多肽、蛋白质、核酸等化学药物，使其顺利进入细胞。一些常见的细胞穿透肽包括Pep-1、Pentratin、PepFact14、Transportan等。

细胞靶向肽：这类多肽的作用主要是引导化学药物或生物活性分子与特定类型的细胞结合，以提高其靶向性和治疗效率。常见的细胞靶向肽包括PEGA、生长激素抑制素类似物、蛙皮素类似物、RGD肽类等。