Liu Dongtao, Ding Bo, Liu Gang, Yang Zhijuan
Department of Gastrointestinal Surgery, General Hospital of Ningxia Medical University, Yinchuan, 750004, Ningxia, China.
Department of Gynecology, General Hospital of Ningxia Medical University, No. 804 South Shengli Street, Xingqing District, Yinchuan, 750004, Ningxia, China.
Clin Exp Med. 2024 Dec 21;25(1):15. doi: 10.1007/s10238-024-01525-7.
FUS-mediated alternative splicing and METTL3-regulated RNA methylation play crucial roles in RNA processing. The purpose of this study was to investigate the interactive roles of FUS and METTL3 in gastric cancer (GC) progression. RNA sequencing data were obtained from the TCGA-STAD dataset. Differentially expressed genes (DEGs) were analyzed across groups stratified by the medians of FUS, METTL3, and NEAT1, respectively. Endoplasmic reticulum (ER) stress markers PERK, IRE1, pIRE1, Bip, and CHOP, as well as related apoptosis stress markers PARP, cleaved-PARP, (Cleaved) Caspase 7, and (Cleaved) Caspase 3, were assessed through western blotting. Alternative splicing and N6-methyladenosine (m(6)A) methylation of specific genes were detected with MeRIP-PCR. Finally, in vivo experiments were conducted using nude mice bearing sh-FUS-transfected HGC27 xenograft tumors. FUS and METTL3 expression levels were elevated in GC tissues. A significant overlap of DEGs was observed between the FUS- and METTL3-stratified groups. These overlapping DEGs were predominantly enriched in mRNA processing and protein processing in the ER. ER stress and apoptosis were induced by sh-FUS or sh-METTL3, which was further enhanced by ER stress inducer tunicamycin in both MKN45 and HGC27 cells. Similarly, DEGs for NEAT1 high- and low-expressed groups were enriched in protein processing in the ER and spliceosome. To a lesser extent, ER stress was also induced by sh-NEAT1 and enhanced by tunicamycin in HGC27 cells. Furthermore, sh-FUS or sh-METTL3 influenced alternative splicing and methylation of specific mRNAs, including FUS, NEAT1, PCNA, MCM2, and BIRC5. Tumor progression was inhibited by sh-FUS in mice, and ER stress and apoptosis were induced, which were further enhanced by tunicamycin. FUS and METTL3 collaborate to facilitate RNA maturation. Inhibiting FUS or METTL3 promoted ER stress and apoptosis and inhibited progression in GC.
FUS介导的可变剪接和METTL3调控的RNA甲基化在RNA加工过程中发挥着关键作用。本研究的目的是探讨FUS和METTL3在胃癌（GC）进展中的相互作用。RNA测序数据来自TCGA-STAD数据集。分别通过FUS、METTL3和NEAT1的中位数对各组进行分层，分析差异表达基因（DEG）。通过蛋白质印迹法评估内质网（ER）应激标志物PERK、IRE1、pIRE1、Bip和CHOP，以及相关的凋亡应激标志物PARP、裂解的PARP、（裂解的）半胱天冬酶7和（裂解的）半胱天冬酶3。用MeRIP-PCR检测特定基因的可变剪接和N6-甲基腺苷（m6A）甲基化。最后，使用携带sh-FUS转染的HGC27异种移植瘤的裸鼠进行体内实验。FUS和METTL3在GC组织中的表达水平升高。在FUS分层组和METTL3分层组之间观察到DEG有显著重叠。这些重叠的DEG主要富集在内质网中的mRNA加工和蛋白质加工过程中。sh-FUS或sh-METTL3诱导内质网应激和凋亡，内质网应激诱导剂衣霉素在MKN45和HGC27细胞中进一步增强了这种作用。同样，NEAT1高表达组和低表达组的DEG在内质网中的蛋白质加工和剪接体中富集。在较小程度上，sh-NEAT1也在HGC27细胞中诱导内质网应激，并被衣霉素增强。此外，sh-FUS或sh-METTL3影响特定mRNA的可变剪接和甲基化，包括FUS、NEAT1、PCNA、MCM2和BIRC5。sh-FUS在小鼠中抑制肿瘤进展，并诱导内质网应激和凋亡，衣霉素进一步增强了这种作用。FUS和METTL3协同促进RNA成熟。抑制FUS或METTL3可促进内质网应激和凋亡，并抑制GC进展。
