School of Chemical and Material Engineering, Jiangnan University, Wuxi, China.
Key Laboratory of Nuclear Medicine, Ministry of Health, Jiangsu Key Laboratory of Molecular Nuclear Medicine, Jiangsu Institute of Nuclear Medicine, Wuxi, China.
Chem Biol Drug Des. 2019 Aug;94(2):1494-1503. doi: 10.1111/cbdd.13530. Epub 2019 May 16.
Legumain, a lysosomal cysteine protease, is critical for pathological progression and has been found to play an important role in the occurrence and development of several cancers. However, its biological functions remain few recognized. To further understand the role of legumain activity in tumor progression, a legumain protease-responsive fluorescent probe was developed in the present study. The probe 1 was synthesized by conjugating an aminoluciferin fluorophore with an alanine-alanine-asparagine (AAN) peptide sequence. The successful synthesis of probe 1 was validated by NMR and MS spectra as well as HPLC analysis. The probe 1 was non-toxic and exhibited great stability in the physiological solutions. More importantly, compared with the aminoluciferin fluorophore, the peptide conjugation may dramatically increase the targeting specificity. Probe 1 was able to effectively detect the legumain activity in living HCT116 cells through fluorescence imaging. All these results implied that probe 1 could act as a promising fluorescent probe specialized for the monitoring of legumain activity in living cells.
组织蛋白酶 L，一种溶酶体半胱氨酸蛋白酶，对病理进程至关重要，并且被发现于多种癌症的发生和发展中扮演着重要角色。然而，其生物学功能仍鲜为人知。为了进一步理解组织蛋白酶 L 活性在肿瘤进展中的作用，本研究开发了一种组织蛋白酶 L 蛋白酶响应型荧光探针。探针 1 通过将氨肽酶荧光团与丙氨酰-丙氨酰-天冬酰胺（AAN）肽序列连接而合成。探针 1 的成功合成通过 NMR 和 MS 谱以及 HPLC 分析得到了验证。探针 1 在生理溶液中无毒且表现出很好的稳定性。更重要的是，与氨肽酶荧光团相比，肽连接可能会极大地提高靶向特异性。探针 1 通过荧光成像能够有效地检测活的 HCT116 细胞中的组织蛋白酶 L 活性。所有这些结果表明，探针 1 可以作为一种有前途的荧光探针，专门用于监测活细胞中的组织蛋白酶 L 活性。
