Priority Research Center, Myunggok Medical Research Institute, College of Medicine, Konyang University, Daejeon, 35365, Republic of Korea.
Biotherapeutics Translational Research Center, Korea Research Institute of Bioscience and Biotechnology, Daejeon, 34141, Republic of Korea.
Cell Oncol (Dordr). 2019 Jun;42(3):275-285. doi: 10.1007/s13402-019-00424-4. Epub 2019 Jan 29.
Previously, it has been reported that homeobox A9 (HOXA9) protein expression is downregulated in lung cancer cells, and that its expression is inversely correlated with the metastatic potential of lung cancer cells both in vitro and in vivo. As such, HOXA9 shows therapeutic potential. The development of therapeutic strategies based on this protein is, however, limited due to its poor membrane permeability. To overcome this problem, we developed a system to deliver HOXA9 protein into non-small cell lung cancer (NSCLC) cells.
First, we constructed a delivery vector expressing polyarginine, a cell-penetrating peptide, as well as HOXA9. The resulting recombinant R10-HOXA9 protein was effectively introduced into A549 and NCI-H1299 NSCLC cells. Next, we examined the roles and molecular mechanisms of recombinant R10-HOXA9 in processes involved in tumor progression. To investigate the therapeutic efficacy of the delivery system, we performed cell motility assays using both in vitro and in vivo experimental models.
We found that recombinant R10-HOXA9 protein reduced the invasion and migration rate, but not the proliferation rate, of the NSCLC cells tested, both in vitro and in vivo. Treatment of NSCLC cells with recombinant R10-HOXA9 protein led to a significant increase in E-cadherin expression. Conversely, we found that the expression of snail family zinc finger 2 (SLUG), a transcriptional repressor of E-cadherin, was markedly decreased. In an experimental metastatic mouse model, recombinant R10-HOXA9 protein was found to effectively reduce the rate of lung cancer cell motility.
Our data suggest that the developed cell-permeable R10-HOXA9 system may serve as a useful tool to prevent NSCLC cell migration and invasion.
先前已有报道称，HOXA9 蛋白在肺癌细胞中的表达下调，其表达水平与肺癌细胞在体外和体内的转移潜能呈负相关。因此，HOXA9 具有治疗潜力。然而，由于其膜通透性差，基于该蛋白开发治疗策略受到限制。为了解决这个问题，我们开发了一种将 HOXA9 蛋白递送到非小细胞肺癌（NSCLC）细胞中的系统。
首先，我们构建了一个表达多聚精氨酸（一种细胞穿透肽）和 HOXA9 的递药载体。所得重组 R10-HOXA9 蛋白可有效地递送至 A549 和 NCI-H1299 NSCLC 细胞。接下来，我们研究了重组 R10-HOXA9 在肿瘤进展相关过程中的作用和分子机制。为了研究递药系统的治疗效果，我们使用体外和体内实验模型进行了细胞迁移实验。
我们发现，重组 R10-HOXA9 蛋白降低了 NSCLC 细胞的侵袭和迁移率，但对增殖率没有影响，无论是在体外还是体内。用重组 R10-HOXA9 蛋白处理 NSCLC 细胞后，E-钙黏蛋白的表达显著增加。相反，我们发现转录抑制因子 E-钙黏蛋白的 snail 家族锌指 2（SLUG）的表达明显降低。在实验性转移性小鼠模型中，重组 R10-HOXA9 蛋白可有效降低肺癌细胞迁移率。
我们的数据表明，开发的细胞穿透性 R10-HOXA9 系统可能成为预防 NSCLC 细胞迁移和侵袭的有用工具。
