The TNF-Related Apoptosis Inducing Ligand (TRAIL) cytokine triggers apoptosis specifically in cancer cells. Susceptibility of a given cell to TRAIL depends on the activity of regulatory proteins, one of the most important of which is BID. The aim of this study was to increase the cytotoxic potential of TRAIL against cancer cells. TRAIL was fused to the BH3 domain of BID. Hence, TRAIL acted not only as an anticancer agent, but also as a specific carrier for the BID fragment. Two fusion protein variants were obtained by genetic engineering, harboring two different linker sequences. The short linker allowed both parts of the fusion protein to fold into their native structures. The long linker influenced the structure of the fused proteins but nonetheless resulted in their highest cytotoxic activity. Optimal buffer formulation was determined for all the analyzed TRAIL variants. Fusing the BH3 domain of BID to TRAIL improved the cytotoxic potential of TRAIL. Further, these findings may be useful for the optimization of other anticancer drugs based on TRAIL, since the appropriate formulation would secure their native structures during prolonged storage.

中文翻译：

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作为重组融合蛋白生产的新型TRAIL变体的细胞毒性得到改善。

TNF相关凋亡诱导配体（TRAIL）细胞因子可特异性触发癌细胞凋亡。给定细胞对TRAIL的敏感性取决于调节蛋白的活性，其中最重要的一项是BID。这项研究的目的是增加TRAIL对癌细胞的细胞毒性潜力。TRAIL与BID的BH3域融合。因此，TRAIL不仅充当抗癌剂，而且还充当BID片段的特定载体。通过遗传工程获得了两个融合蛋白变体，它们带有两个不同的接头序列。短连接子允许融合蛋白的两个部分折叠成其天然结构。长接头影响融合蛋白的结构，但仍导致其最高的细胞毒活性。确定所有分析的TRAIL变体的最佳缓冲液配方。将BID的BH3结构域与TRAIL融合可提高TRAIL的细胞毒性潜力。此外，这些发现对于优化基于TRAIL的其他抗癌药物可能是有用的，因为适当的配方可以在长期保存期间确保其天然结构。