禽呼肠孤病毒σC蛋白抗肿瘤作用及其分子机制的研究

Malignant tumor becomes the medical problem with high morbidity, high mortality and no effective medicines, and biological therapy involved with oncolytic viruses would be promising for novel medicines against tumor. Avian reovirus (ARV) has been demonstrated to posses the anti-tumor activity , and its critical structural protein σC is able to induce cell apoptosis and immune responses, but what and how ARV σC functions during ARV inhibits tumors. This study would utilize eukaryotic expression plasmid pVAX1-σC-HA to transfect Hepatocellular cell and inject into tumor-bearing mice, and then examine the effects of ARV σC on apoptosis and immune responses in vivo and in vitro. The status of apoptosis and oxidation-reduction, mitochondrial membrane potential and distribution, as well as the expression changes of caspase and apoptosis-associated genes would be investigated to reveal the molecular basis of ARV σC-inducing tumor cell apoptosis. The expression changes of interferon-stimulating genes and MHC-I, the populations of T lymphocytes and NK cells together with cytokines in spleens from tumor-bearing mice would be investigated to elucidate the effects of ARV σC on host anti-tumor immune responses. These data above would help to clarify the anti-tumor activity of ARV σC, and further understand the molecular mechanism of σC-inducing hepatocellular apoptosis and anti-tumor immune responses, which would contribute to develop novel medicines for malignant tumor.

恶性肿瘤以高发病率、高死亡率和无特效药成为医学难题，以病毒溶瘤为特点的生物治疗有望带来新突破。禽呼肠孤病毒（ARV）已被证明具有抗肿瘤作用，其重要结构蛋白σC具有凋亡诱导和免疫刺激活性 ，但其在ARV抗肿瘤过程中作用尚不清楚。本研究拟以人肝癌细胞和肝癌的荷瘤小鼠为研究对象，从体内和体外考察ARV σC蛋白诱导肝癌细胞和瘤体发生凋亡及免疫反应的特性。通过检测转染pVAX1-σC-HA后的肝癌细胞凋亡状态、氧化还原状态、线粒体膜电位及分布、Caspase和凋亡相关基因的表达等，揭示ARV σC蛋白诱导人肝癌细胞凋亡的分子基础。通过检测荷瘤小鼠的肿瘤组织中干扰素刺激因子和MHC-I分子的表达水平，分析脾中T淋巴细胞亚群、NK细胞数和细胞因子的表达，解析ARV σC蛋白诱导的抗肿瘤免疫应答。通过上述研究，明确ARV σC蛋白的抗肿瘤作用，并阐明其分子机制，为研发新型抗肿瘤药物奠定基础。

恶性肿瘤以高发病率、高死亡率和无特效药成为医学难题，以病毒溶瘤为特点的生物治疗有望带来新突破。禽呼肠孤病毒（Avian reovirus,ARV）已被证明具有抗肿瘤作用，其重要结构蛋白σC具有凋亡诱导和免疫刺激活性 ，但其在ARV抗肿瘤过程中作用尚不清楚。本研究表明禽呼肠孤病毒σC蛋白可显著降低肝癌细胞的存活率，抑制肿瘤的生长，具有明显的抗肿瘤作用活性。并且，σC蛋白可诱导肝癌细胞发生凋亡、上调胞内ROS水平及激活TLR3和MDA5免疫信号通路因子表达。σC蛋白还可促使宿主脾内淋巴细胞增殖，介导瘤体内凋亡相关蛋白表达，并激活PI3K/Akt/mTOR信号通路。以上研究结果，明确了ARV σC蛋白的抗肿瘤作用，阐明了其可能的分子机制，为进一步研发新型抗肿瘤药物提供实验数据和理论基础。