KIAA1324是一种跨膜蛋白，被广泛报道为多种癌症中的肿瘤抑制剂和良好预后标志物，包括胃癌。在本研究中，我们报告了N-连接糖基化在KIAA1324中作为功能性翻译后修饰的作用。失去N-连接糖基化能力使KIAA1324无法抑制癌细胞的增殖和迁移。此外，我们证明KIAA1324经历了富卡糖化，这是一种由富卡糖基转移酶介导的N-糖基修饰。富卡糖化的抑制也显著抑制了KIAA1324诱导的胃癌细胞生长抑制和凋亡。此外，失去N-连接糖基化也抑制了KIAA1324介导的凋亡和肿瘤逆转。RNA测序分析显示，与凋亡和细胞周期阻滞途径最相关的基因受KIAA1324及其N-连接糖基化的调控，并且基因调控网络分析提示KIAA1324在转录水平上具有抗肿瘤作用的新靶点。N-连接糖基化的阻断通过快速蛋白酶体降解降低了蛋白稳定性。非糖基化突变体还表现出改变的定位和丧失的凋亡活性，抑制了GRP78和caspase 7之间的相互作用。这些数据表明N-连接糖基化对于KIAA1324蛋白在胃癌进展中的抑制作用至关重要，并且表明KIAA1324可能通过靶向具有N-连接糖基化的癌相关基因产生抗肿瘤效应。总之，我们的研究表明，包括N-连接糖基化和富卡糖基化在内的KIAA1324的翻译后修饰是考虑癌症预后和治疗改进的必要因素。© 2023. The Author(s).

KIAA1324 is a transmembrane protein largely reported as a tumor suppressor and favorable prognosis marker in various cancers, including gastric cancer. In this study, we report the role of N-linked glycosylation in KIAA1324 as a functional post-translational modification (PTM). Loss of N-linked glycosylation eliminated the potential of KIAA1324 to suppress cancer cell proliferation and migration. Furthermore, we demonstrated that KIAA1324 undergoes fucosylation, a modification of the N-glycan mediated by fucosyltransferase, and inhibition of fucosylation also significantly suppressed KIAA1324-induced cell growth inhibition and apoptosis of gastric cancer cells. In addition, KIAA1324-mediated apoptosis and tumor regression were inhibited by the loss of N-linked glycosylation. RNA sequencing (RNAseq) analysis revealed that genes most relevant to the apoptosis and cell cycle arrest pathways were modulated by KIAA1324 with the N-linked glycosylation, and Gene Regulatory Network (GRN) analysis suggested novel targets of KIAA1324 for anti-tumor effects in the transcription level. The N-linked glycosylation blockade decreased protein stability through rapid proteasomal degradation. The non-glycosylated mutant also showed altered localization and lost apoptotic activity that inhibits the interaction between GRP78 and caspase 7. These data demonstrate that N-linked glycosylation of KIAA1324 is essential for the suppressive role of KIAA1324 protein in gastric cancer progression and indicates that KIAA1324 may have anti-tumor effects by targeting cancer-related genes with N-linked glycosylation. In conclusion, our study suggests the PTM of KIAA1324 including N-linked glycosylation and fucosylation is a necessary factor to consider for cancer prognosis and therapy improvement.© 2023. The Author(s).