目的:有限的研究集中在二氢尿苷合酶(DUS)家族成员在人类肿瘤中的作用。我们先前的发现表明二氢尿苷合酶4样(DUS4L)对肺腺癌(LUAD)A549细胞增殖和凋亡的影响,然而,其在LUAD中更广泛的功能和调节机制仍然难以捉摸。
方法:使用LUAD组织微阵列和免疫组织化学(IHC)染色,我们验证了LUAD患者中DUS4L蛋白表达水平的差异,并评估了其临床意义.使用短发夹RNA(shRNA)对抗DUS4L(sh-DUS4L-2)的其他实验,LUAD细胞系,细胞功能测定(包括伤口愈合,Transwell迁移和入侵,菌落形成,和凋亡测定),和小鼠肿瘤异种移植以检查DUS4L在LUAD进展中的生物学作用。RNA测序,蛋白质组学分析,质谱,和免疫共沉淀实验进行鉴定和验证DUS4L调节的下游靶基因和信号通路。
结果:我们在LUAD组织中发现了DUS4L的一致上调。体外和体内实验强调了DUS4L下调对LUAD进展的抑制作用,包括迁移,入侵,和扩散。机械上,发现DUS4L与信号分子GRB2相互作用,通过PI3K/AKT和ERK/MAPK途径诱导上皮-间质转化(EMT)促进LUAD进展和转移。
结论:我们的结果确立了DUS4L在驱动LUAD进展和转移中的功能作用,暗示其作为LUAD候选治疗靶点的潜力。
OBJECTIVE: Limited research has focused on the role of dihydrouridine synthases (DUS) family members in human tumors. Our previous findings indicated an impact of dihydrouridine synthase 4 like (DUS4L) on cell proliferation and apoptosis in lung adenocarcinoma (LUAD) A549 cell, yet its broader functions and regulatory mechanisms in LUAD remain elusive.
METHODS: Using a LUAD tissue microarray and immunohistochemical (IHC) staining, we validated variations in DUS4L protein expression levels among LUAD patients and assessed its clinical significance. Additional experiments using short hairpin RNA (shRNA) against DUS4L (sh-DUS4L-2), LUAD cell lines, cell function assays (including wound healing, transwell migration and invasion, colony formation, and apoptosis assays), and mouse tumor xenografts were performed to examine the biological roles of DUS4L in LUAD progression. RNA sequencing, proteomic analyses, mass spectrometry, and co-immunoprecipitation experiments were conducted to identify and validate DUS4L-regulated downstream target genes and signaling pathways.
RESULTS: We identified a consistent upregulation of DUS4L in LUAD tissues. In vitro and in vivo experiments underscored the inhibitory effect of DUS4L downregulation on LUAD progression, including migration, invasion, and proliferation. Mechanistically, DUS4L was found to interact with the signaling molecule GRB2, promoting LUAD progression and metastasis by inducing epithelial-mesenchymal transition (EMT) via the PI3K/AKT and ERK/MAPK pathways.
CONCLUSIONS: Our results establish the functional role of DUS4L in driving the progression and metastasis of LUAD, implicating its potential as a candidate therapeutic target for LUAD.