Jiang Jianwu, Chang Wei, Fu Yang, Gao Yongshun, Zhao Chunlin, Zhang Xiefu, Zhang Shuijun
a Department of Gastrointestinal Surgery, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
b Department of Henan Key Laboratory of Digestive Organ Transplantation, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, 450052, China.
Biochem Cell Biol. 2019 Apr;97(2):91-99. doi: 10.1139/bcb-2018-0034. Epub 2019 Jan 25.
This study investigated the role and action of the Salvador 1 protein (SAV1, also called WW45) in colorectal cancer (CRC). For this, CRC SW480 and HCT116 cells were infected with lentiviruses of SAV1 overexpression vector (lenti-SAV1) and SAV1 short hairpin RNA (sh-SAV1) to overexpress and silence SAV1 respectively, or transfected with microRNA-21 (miR-21) mimic to overexpress miR-21. Relative mRNA levels of SAV1 and relative miR-21 levels in CRC tissues or cells were detected. The effects of SAV1 and miR-21 on cell proliferation and apoptosis were evaluated using the MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay and annexin V - fluorescein isothiocyanate (FITC) - propidium iodide (PI) flow cytometry, respectively. Our results revealed that SAV1 was downregulated in CRC tissues compared with the adjacent noncancerous tissues. Furthermore, SAV1 overexpression inhibited proliferation and promoted apoptosis in SW480 and HCT116 cells, whereas knockdown of SAV1 exerted the opposite effect. Additionally, the tumorigenesis of SW480 cells in xenografted mice was significantly inhibited by SAV1 overexpression but promoted by SAV1 knockdown. MiR-21 levels significantly and negatively correlated with SAV1 expression in CRC tissues. More importantly, miR-21 overexpression significantly abolished the SAV1-mediated inhibition of proliferation and stimulation of apoptosis of SW480. In conclusion, SAV1 suppresses tumor growth in CRC and is regulated by miR-21.
本研究调查了萨尔瓦多1蛋白（SAV1，也称为WW45）在结直肠癌（CRC）中的作用及作用机制。为此，分别用SAV1过表达载体慢病毒（lenti-SAV1）和SAV1短发夹RNA（sh-SAV1）感染CRC SW480和HCT116细胞，以分别过表达和沉默SAV1，或用微小RNA-21（miR-21）模拟物转染以过表达miR-21。检测CRC组织或细胞中SAV1的相对mRNA水平和相对miR-21水平。分别使用MTT [3-(4,5-二甲基噻唑-2-基)-2,5-二苯基四氮唑溴盐] 法和膜联蛋白V - 异硫氰酸荧光素（FITC） - 碘化丙啶（PI）流式细胞术评估SAV1和miR-21对细胞增殖和凋亡的影响。我们的结果显示，与相邻的非癌组织相比，CRC组织中SAV1表达下调。此外，SAV1过表达抑制SW480和HCT116细胞的增殖并促进其凋亡，而敲低SAV1则产生相反的效果。此外，SAV1过表达显著抑制了SW480细胞在异种移植小鼠中的肿瘤发生，但敲低SAV1则促进了肿瘤发生。CRC组织中miR-21水平与SAV1表达呈显著负相关。更重要的是，miR-21过表达显著消除了SAV1介导的对SW480增殖的抑制和对凋亡的刺激作用。总之，SAV1抑制CRC中的肿瘤生长，并受miR-21调控。
