Abstract: Objective　To investigate the effect of interferon-induced protein with tetratricopeptide repeats 1 (IFIT1) on the progression of pancreatic cancer.Methods　The expression of IFIT1 in pancreatic cancer samples was analyzed using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets. The mRNA levels of IFIT1 were detected by real-time quantitative PCR in pancreatic cancer cell lines (AsPC-1, MiaPaCa-2, BxPC-3, Patu8988, Panc-1, and CFPAC-1) and normal pancreatic cells. IFIT1 knockout cells were generated using the CRISPR/Cas9 system in AsPC-1 and BxPC-3 cells. AsPC-1 cells were divided into AsPC-1-ko-NC group (negative control group) and AsPC-1-ko-IFIT1 group (IFIT1 knockout group). Similarly, BxPC-3 cells were divided into BxPC-3-ko-NC group (negative control group) and BxPC-3-ko-IFIT1 group (IFIT1 knockout group). Cell viability was assessed using the cell counting kit-8 (CCK-8) assay in the four groups. Wound healing assay was performed to observe the closure status after 24 h and to evaluate cell migration ability in the four groups. Transwell assay was used to detect cell invasion ability in the four groups. The expression levels of IFIT1, β-catenin, and EMT-related proteins (E-cadherin, N-cadherin, Vimentin) in the four groups were detected by Western blot. Subsequently, the above four groups of cells were respectively injected subcutaneously into BALB/c nude mice, the volume and weight of the transplanted tumors were measured, and the expression of proliferation markers (Ki-67) in the transplanted tumors were measured. Results　Compared with normal tissues, the expression level of IFIT1 was significantly elevated in pancreatic cancer tissues. Following IFIT1 knockout in AsPC-1 and BxPC-3 cells, compared with the respective negative control groups (AsPC-1-ko-NC and BxPC-3-ko-NC groups), the AsPC-1-ko IFIT1 and BxPC-3-ko-IFIT1 groups exhibited decreased cell proliferation activity, migration, and invasion ability. In these knockout groups, E-cadherin protein expression was increased, while the expression of IFIT1, N-cadherin, Vimentin, and β-catenin was decreased. The in vivo xenograft tumor assay showed that compared with the negative control groups, the AsPC-1-ko-IFIT1 and BxPC-3-ko-IFIT1 groups had reduced tumor volume and weight, as well as decreased Ki-67 expression in the tumor tissues. Conclusion　IFIT1 promotes the proliferation, migration, invasion, and in vivo tumor growth of pancreatic cancer cells by activating the Wnt/β-catenin signaling pathway. EMT is regulated by IFIT1. IFIT1 may serve as a potential therapeutic target for pancreatic cancer.

Key words: pancreatic cancer, IFIT1, Wnt/β-catenin signaling pathway, migration, invade and attack

摘要： 目的　探讨干扰素诱导的四肽重复蛋白 1(IFIT1)对胰腺癌发展的影响。方法　使用癌症基因组图谱 (TCGA)和基因表达综合(GEO)数据集探索胰腺癌样本中IFIT1的表达;通过实时荧光定量PCR方法检测胰腺癌 细胞系(AsPC-1、MiaPaCa-2、BxPC-3、Patu8988、Panc-1 和 CFPAC-1)和正常胰腺细胞IFIT1 mRNA含量;采用 CRISPR/Cas9方式,构建AsPC-1细胞和BxPC-3细胞的IFIT1敲除细胞,将AsPC-1细胞分为AsPC-1-ko-NC组(阴 性对照组)和AsPC-1-ko-IFIT1组(IFIT1敲除组),BxPC-3细胞分为BxPC-3-ko-NC组(阴性对照组)和BxPC-3-ko IFIT1组(IFIT1敲除组),通过细胞增殖检测试剂盒(CCK-8)检测四组细胞活力;采用细胞划痕实验观察四组细胞 24 h后愈合情况,检测细胞迁移能力;采用Transwell检测四组细胞侵袭能力;通过Western blot法分别检测四组细 胞中IFIT1、β-catenin及上皮-间质转化(EMT)相关蛋白(E-cadherin、N-cadherin、Vimentin)的表达水平。随后,将上 述四组细胞分别皮下注射至BALB/c裸鼠体内,检测移植瘤的体积与质量,并检测移植瘤中增殖标志物(Ki-67)的 表达。结果　与正常组织相比,胰腺癌组织中IFIT1的表达水平显著升高;与AsPC-1-ko-NC组、BxPC-3-ko-NC组相 比,敲除IFIT1后,AsPC-1-ko-IFIT1组与BxPC-3-ko-IFIT1组细胞增殖活性、迁移和侵袭能力下降,E-cadherin蛋白表 达升高,IFIT1、N-cadherin、Vimentin和β-catenin蛋白表达降低;裸鼠荷瘤实验结果显示,与AsPC-1-ko-NC组和 BxPC-3-ko-NC相比,敲除IFIT1后,AsPC-1-ko-IFIT1组和BxPC-3-ko-IFIT1组中移植瘤体积和质量降低,移植瘤中 Ki-67表达下降。结论　IFIT1 通过激活 Wnt/β-catenin 通路来增加胰腺癌细胞的增殖、迁移、侵袭和体内肿瘤生 长,EMT可以受到 IFIT1 的调节,IFIT1 或可作为胰腺癌的潜在治疗靶点。

关键词: 胰腺癌, 干扰素诱导的四肽重复蛋白 1, Wnt/β-catenin信号通路, 迁移, 侵袭