Design and Synthesis of the Artificial Luminescent Death Ligands Based on C3-Symmetric Cyclometalated Iridium Complexes for Selective Staining and Apoptosis Induction of Cancer Cells

肿瘤坏死因子相关凋亡诱导配体（TNF-related apoptosis-inducing ligand，TRAIL）具有C3对称的同源三聚体结构，通过与细胞表面的死亡受体（death receptor，DR）相互作用诱导多种肿瘤细胞和组织的凋亡。本研究设计合成了一种新型的C3-对称三环化铱配合物，该配合物具有诱导细胞凋亡的激动剂活性和肿瘤细胞的荧光成像活性，用含有DR 5结合环肽的铱配合物对Jurkat细胞进行染色实验，发现绿色发射定位于细胞膜上。流式细胞仪分析表明，癌细胞（Jurkat细胞、Molt-4细胞、K562细胞）DR 5的表达与Ir配合物的发光强度相关。Ir配合物的优化，以改善其TRAIL样活性正在进行中。

TNF-related apoptosis-inducing ligand (TRAIL) having a C3-symmetric homotrimeric structure induces the apoptosis in various tumor cells and tissues through the interaction with death receptor (DR) on cell surface. In this study, we have addressed the design and synthesis of new C3-symmetric tris-cyclometalated Ir complexes having dual activity both agonist activity for apoptosis induction and luminescent imaging of cancer cells.Staining experiments of Jurkat cell with Ir complex having the DR5 binding cyclic peptide suggested that green emission was localized on the cell membrane. Moreover, flow cytometer analysis suggested that the correlation between DR5 expressions of cancer cells (Jurkat cells, Molt-4 cells, K562 cells) and emission intensities derived from Ir complex. Optimizations of Ir complexes for improvement of their TRAIL-like activity are undergoing.