PDF(Pubmed)
Abstract：
Exosomes are released by various cells, including natural killer (NK) cells and transport signaling molecules for the intercellular communication. Hepatocellular carcinoma (HCC), also known as primary liver cancer, is often inoperable and difficult to accurate diagnosis. Notably, the prognosis and underlying mechanisms of HCC are not fully understood. Exosomes-derived NK cells (NK-exos) express unique cytotoxic proteins with a killing ability in tumors and can easily penetrate tumor tissues to improve their targeting ability. NK cell functions, inducing cellular cytotoxicity are modulated by cytokines such as interleukin (IL)-15 and IL-21. However, the mechanisms and effects of cytokines-stimulated NK-exos for the treatment of liver cancer, including HCC, are not well known. In this study, we aimed to investigate the synergistic anti-tumor effects of NK-exos stimulated with IL-15 and IL-21 (NK-exosIL-15/21) in Hep3B cells. Our findings revealed that NK-exosIL-15/21 expressed cytotoxic proteins (perforin and granzyme B) and contained typical exosome markers (CD9 and CD63) within the size range of 100-150 nm. Moreover, we demonstrated that NK-exosIL-15/21 induced the enhancement of cytotoxicity and apoptotic activity in Hep3B cells by activating the specific pro-apoptotic proteins (Bax, cleaved caspase 3, cleaved PARP, perforin, and granzyme B) and inhibiting the anti-apoptotic protein (Bcl-2). In summary, our results suggest that NK-exosIL-15/21 regulate strong anti-tumor effects of HCC cells, by increasing the cytotoxicity and apoptosis through the activation of specific cytotoxic molecules.
摘要：
外泌体由各种细胞释放，包括自然杀伤（NK）细胞和细胞间通讯的转运信号分子。肝细胞癌（HCC），也被称为原发性肝癌，往往无法手术，难以准确诊断。值得注意的是,HCC的预后和潜在机制尚不完全清楚。外泌体来源的NK细胞（NK-exos）表达独特的细胞毒性蛋白，在肿瘤中具有杀伤能力，可以很容易地穿透肿瘤组织以提高其靶向能力。NK细胞功能，诱导细胞的细胞毒性由细胞因子如白细胞介素(IL)-15和IL-21调节。然而,细胞因子刺激的NK-exos治疗肝癌的机制和效果，包括HCC，不是众所周知的。在这项研究中,我们旨在研究IL-15和IL-21（NK-exosIL-15/21）刺激的NK-exos在Hep3B细胞中的协同抗肿瘤作用。我们的发现表明，NK-exosIL-15/21表达细胞毒性蛋白（穿孔素和颗粒酶B），并在100-150nm的大小范围内含有典型的外泌体标记（CD9和CD63）。此外，我们证明了NK-exosIL-15/21通过激活特定的促凋亡蛋白（Bax，裂解的半胱天冬酶3，裂解的PARP，穿孔素,和颗粒酶B）并抑制抗凋亡蛋白（Bcl-2）。总之,我们的结果表明，NK-exosIL-15/21调节肝癌细胞的强抗肿瘤作用，通过激活特定的细胞毒性分子来增加细胞毒性和细胞凋亡。
