Ding Lixian, Li Bin, Yu Xiaotong, Li Zhongsheng, Li Xinglong, Dang Shuwei, Lv Qiang, Wei Jiufeng, Sun Haixia, Chen Hongsheng, Liu Ming, Li Guodong
1Department of General Surgery, The Fourth Affiliated Hospital of Harbin Medical University, No. 37 Yiyuan Street, Nangang District, Harbin, 150001 Heilongjiang China.
2Bio-Bank of Department of General Surgery, The Fourth Affiliated Hospital of Harbin Medical University, No. 37 Yiyuan Street, Nangang District, Harbin, 150001 Heilongjiang China.
Cancer Cell Int. 2020 Apr 15;20:125. doi: 10.1186/s12935-020-01199-7. eCollection 2020.
Kinesin superfamily proteins (KIFs) can transport membranous organelles and protein complexes in an ATP-dependent manner. Kinesin family member 15 (KIF15) is overexpressed in various cancers. However, the function of KIF15 in gastric cancer (GC) is still unclear.
GC patients' data from The Cancer Genome Atlas (TCGA) were analyzed by bioinformatics methods. The expression of KIF15 was examined in GC and paracarcinoma tissues from 41 patients to verify the analysis results. The relationship between KIF15 expression and clinical characteristics were also observed by bioinformatics methods. Kaplan-Meier survival analysis of 122 GC patients in our hospital was performed to explore the relationship between KIF15 expression levels and GC patients' prognosis. KIF15 was downregulated in GC cell lines AGS and SGC-7901 by transfecting a lentivirus-mediated shRNA plasmid targeting KIF15. In vitro, GC cell proliferation and apoptosis were detected by MTT assay, colony formation assay, and Annexin V-APC staining. In vivo, xenograft experiments were used to verify the in vitro results. Furthermore, Human Apoptosis Antibody Array kit was used to screen possible targets of KIF15 in GC cell lines.
The bioinformatics results showed that KIF15 expression levels were higher in GC tissues than in normal tissues. IHC showed same results. High expression of KIF15 was statistical correlated with high age and early histologic stage. Kaplan-Meier curves indicated that high KIF15 expression predict poor prognosis in patients with GC. MTT assay and colony formation assay showed that KIF15 promote GC cell proliferation. Annexin V-APC staining found that KIF15 can inhibit GC cell apoptosis. Xenograft experiments reveal that downregulating KIF15 can inhibit GC tumor growth and promote GC apoptosis. Through detection of 43 anti-apoptotic proteins by the Human Apoptosis Antibody Array kit, it was confirmed that knocking down KIF15 can reduce seven anti-apoptotic proteins expression.
Taken together, our study revealed a critical role for KIF15 to inhibit GC cell apoptosis and promote GC cell proliferation. KIF15 may decrease anti-apoptotic proteins expression by regulating apoptosis pathways. High expression of KIF15 predicts a poor prognosis in patients with GC. KIF15 might be a novel prognostic biomarker and a therapeutic target for GC.
驱动蛋白超家族蛋白（KIFs）能够以ATP依赖的方式转运膜性细胞器和蛋白质复合物。驱动蛋白家族成员15（KIF15）在多种癌症中过表达。然而，KIF15在胃癌（GC）中的功能仍不清楚。
采用生物信息学方法分析来自癌症基因组图谱（TCGA）的GC患者数据。检测41例患者GC组织和癌旁组织中KIF15的表达，以验证分析结果。还通过生物信息学方法观察KIF15表达与临床特征之间的关系。对我院122例GC患者进行Kaplan-Meier生存分析，以探讨KIF15表达水平与GC患者预后的关系。通过转染靶向KIF15的慢病毒介导的shRNA质粒，在GC细胞系AGS和SGC-7901中下调KIF15。在体外，通过MTT法、集落形成试验和Annexin V-APC染色检测GC细胞增殖和凋亡。在体内，采用异种移植实验验证体外结果。此外，使用人凋亡抗体阵列试剂盒筛选GC细胞系中KIF15可能的靶点。
生物信息学结果显示，GC组织中KIF15表达水平高于正常组织。免疫组化显示相同结果。KIF15的高表达与高龄和早期组织学分期具有统计学相关性。Kaplan-Meier曲线表明，KIF15高表达预示GC患者预后不良。MTT法和集落形成试验表明，KIF15促进GC细胞增殖。Annexin V-APC染色发现，KIF15可抑制GC细胞凋亡。异种移植实验表明，下调KIF15可抑制GC肿瘤生长并促进GC凋亡。通过人凋亡抗体阵列试剂盒检测43种抗凋亡蛋白，证实敲低KIF15可降低7种抗凋亡蛋白的表达。
综上所述，我们的研究揭示了KIF15在抑制GC细胞凋亡和促进GC细胞增殖中的关键作用。KIF15可能通过调节凋亡途径降低抗凋亡蛋白的表达。KIF15高表达预示GC患者预后不良。KIF15可能是GC的一种新型预后生物标志物和治疗靶点。
