Zhang Hong, Zhang Haojian, Zhu Jiye, Liu Huan, Zhou Qin
Department of Oncology, The First Hospital of Hunan University of Chinese Medicine, No.95 Shaoshan Middle Road, Yuhua District, Changsha, 410007, Hunan, China.
Cancer Cell Int. 2021 Nov 27;21(1):628. doi: 10.1186/s12935-021-02336-6.
Non-small cell lung cancer (NSCLC) accounts for more than 80% of lung cancers, which is the most common malignant tumor worldwide. Polypeptide extract from scorpion venom (PESV) has been reported to inhibit NSCLC process. The present study aims to reveal the roles of PESV in NSCLC progression under hypoxia and the inner mechanism.
The expression levels of circular RNA 0016760 (circ_0016760) and microRNA-29b (miR-29b) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Protein expression was determined by western blot and immunohistochemistry assays. Cell migration, invasion, proliferation and tube formation were investigated by transwell, cell colony formation, 3-(4,5-Dimethylthazol-2-yl)-2,5-diphenyltetrazolium bromide and tube formation assays. The impacts between PESV and circ_0016760 overexpression on tumor growth in vivo were investigated by in vivo tumor formation assay.
Circ_0016760 expression was dramatically upregulated in NSCLC tissues and cells, compared with adjacent lung tissues and cells, respectively. PESV treatment downregulated circ_0016760 expression. Circ_0016760 silencing or PESV treatment repressed cell migration, invasion, proliferation and tube formation under hypoxia in NSCLC cells. Circ_0016760 overexpression restored the effects of PESV treatment on NSCLC process under hypoxia. Additionally, circ_0016760 acted as a sponge of miR-29b, and miR-29b bound to HIF1A. Meanwhile, miR-29b inhibitor impaired the influences of circ_0016760 knockdown on NSCLC process under hypoxia. Further, ectopic circ_0016760 expression restrained the effects of PESV exposure on tumor formation in vivo.
Circ_0016760 overexpression counteracted PESV-induced repression of NSCLC cell malignancy and angiogenesis under hypoxia through miR-29b/HIF1A axis.
非小细胞肺癌（NSCLC）占肺癌的80%以上，是全球最常见的恶性肿瘤。据报道，蝎毒多肽提取物（PESV）可抑制NSCLC进程。本研究旨在揭示PESV在缺氧条件下对NSCLC进展的作用及其内在机制。
采用定量实时聚合酶链反应（qRT-PCR）检测环状RNA 0016760（circ_0016760）和微小RNA-29b（miR-29b）的表达水平。通过蛋白质印迹法和免疫组织化学分析确定蛋白质表达。采用Transwell法、细胞集落形成实验、3-(4,5-二甲基噻唑-2)-2,5-二苯基四氮唑溴盐法和管形成实验研究细胞迁移、侵袭、增殖和管形成情况。通过体内肿瘤形成实验研究PESV和circ_0016760过表达对体内肿瘤生长的影响。
与相邻肺组织和细胞相比，circ_0016760在NSCLC组织和细胞中的表达显著上调。PESV处理可下调circ_0016760的表达。circ_0016760沉默或PESV处理可抑制缺氧条件下NSCLC细胞的迁移、侵袭、增殖和管形成。circ_0016760过表达恢复了PESV处理对缺氧条件下NSCLC进程的影响。此外，circ_0016760作为miR-29b的海绵，miR-29b与HIF1A结合。同时，miR-29b抑制剂削弱了circ_0016760敲低对缺氧条件下NSCLC进程的影响。此外，异位circ_0016760表达抑制了PESV暴露对体内肿瘤形成的影响。
circ_0016760过表达通过miR-29b/HIF1A轴抵消了PESV诱导的缺氧条件下NSCLC细胞恶性和血管生成的抑制作用。
