Genome-scale CRISPR-Cas9 screening technology is a powerful tool to systematically identify genes essential for cancer cell survival. Herein, TKOv3, a genome-scale CRISPR-Cas9 knock-out library, was screened in the gastric cancer (GC) cells, and relevant validation experiments were performed. We obtained 854 essential genes for the AGS cell line, and 184 were novel essential genes. After knocking down essential genes: SPC25, DHX37, ABCE1, SNRPB, TOP3A, RUVBL1, CIT, TACC3 and MTBP, cell viability and proliferation were significantly decreased. Then, we analysed the detected essential genes at different time points and proved more characteristic genes might appear with the extension of selection. After progressive selection using a series of open datasets, 41 essential genes were identified as potential drug targets. Among them, methyltransferase 1 (METTL1) was over expressed in GC tissues. High METTL1 expression was associated with poor prognosis among 3 of 6 GC cohorts. Furthermore, GC cells growth was significantly inhibited after the down-regulation of METTL1 in vitro and in vivo. Function analysis revealed that METTL1 might play a role in the cell cycle through AKT/STAT3 pathways. In conclusion, compared with existing genome-scale screenings, we obtained 184 novel essential genes. Among them, METTL1 was validated as a potential therapeutic target of GC.

基因组规模的 CRISPR-Cas9 筛选技术是一种强大的工具，可以系统地识别对癌细胞生存至关重要的基因。本文在胃癌（GC）细胞中筛选出基因组规模的CRISPR-Cas9敲除文库TKOv3，并进行了相关验证实验。我们获得了AGS细胞系的854个必需基因，其中184个是新的必需基因。敲除必需基因：SPC25、DHX37、ABCE1、SNRPB、TOP3A、RUVBL1、CIT、TACC3和MTBP后，细胞活力和增殖显着降低。然后，我们分析了在不同时间点检测到的必需基因，证明随着选择的扩大，可能会出现更多的特征基因。在使用一系列开放数据集进行渐进式选择后，41 个必需基因被确定为潜在的药物靶点。其中，甲基转移酶 1 (METTL1) 在 GC 组织中过度表达。在 6 个 GC 队列中的 3 个中，高 METTL1 表达与不良预后相关。此外，在体外和体内下调 METTL1 后，GC 细胞的生长受到显着抑制。功能分析显示METTL1可能通过AKT/STAT3途径在细胞周期中发挥作用。总之，与现有的基因组规模筛选相比，我们获得了 184 个新的必需基因。其中，METTL1被验证为GC的潜在治疗靶点。功能分析显示METTL1可能通过AKT/STAT3途径在细胞周期中发挥作用。总之，与现有的基因组规模筛选相比，我们获得了 184 个新的必需基因。其中，METTL1被验证为GC的潜在治疗靶点。功能分析显示METTL1可能通过AKT/STAT3途径在细胞周期中发挥作用。总之，与现有的基因组规模筛选相比，我们获得了 184 个新的必需基因。其中，METTL1被验证为GC的潜在治疗靶点。