Abstract：
Upstream-stimulating factor 1 (USF1) is a ubiquitously expressed transcription factor implicated in multiple cellular processes, including metabolism and proliferation. This study focused on the function of USF1 in glycolysis and the malignant development of prostate adenocarcinoma (PRAD). Bioinformatics predictions suggested that USF1 is poorly expressed in PRAD. The clinical PRAD samples revealed a low level of USF1, which was correlated with an unfavorable prognosis. Artificial upregulation of USF1 significantly repressed glycolytic activity in PRAD cells and reduced cell growth and metastasis in vitro and in vivo. Potential downstream genes of USF1 were probed by integrated bioinformatics analyses. The chromatin immunoprecipitation and luciferase assays indicated that USF1 bound to the α-ketoglutarate-dependent dioxygenase alkB homolog 5 (ALKBH5) promoter for transcription activation. Flightless I (FLII) was identified as the gene showing the highest degree of correlation with ALKBH5. As an m6A demethylase, ALKBH5 enhanced FLII mRNA stability by inducing m6A demethylation in an m6A-YTH N6-methyladenosine RNA-binding protein F2 (YTHDF2)-dependent manner. Either silencing of ALKBH5 or FLII blocked the role of USF1 in PARD cells and restored glycolysis, cell proliferation, and invasion. This study demonstrates that USF1 activates ALKBH5 to stabilize FLII mRNA in an m6A-YTHDF2-dependent manner, thereby repressing glycolysis processes and the progression of PRAD.
摘要：
上游刺激因子1（USF1）是一种广泛表达的转录因子，涉及多个细胞过程，包括新陈代谢和增殖。本研究集中于USF1在糖酵解和前列腺腺癌（PRAD）恶性发展中的功能。生物信息学预测表明USF1在PRAD中表达不良。临床PRAD样本显示USF1水平较低，这与不良预后相关。USF1的人工上调显着抑制了PRAD细胞中的糖酵解活性，并在体外和体内降低了细胞生长和转移。通过整合的生物信息学分析探测了USF1的潜在下游基因。染色质免疫沉淀和荧光素酶测定表明，USF1与α-酮戊二酸依赖性双加氧酶alkB同源物5（ALKBH5）启动子结合以进行转录激活。FlightlessI（FLII）被鉴定为与ALKBH5相关程度最高的基因。作为一种m6A去甲基酶，ALKBH5通过以m6A-YTHN6-甲基腺苷RNA结合蛋白F2（YTHDF2）依赖性方式诱导m6A去甲基化来增强FLIImRNA的稳定性。ALKBH5或FLII的沉默阻断了USF1在PARD细胞中的作用并恢复糖酵解,细胞增殖，和入侵。这项研究表明，USF1激活ALKBH5以m6A-YTHDF2依赖性方式稳定FLIImRNA，从而抑制糖酵解过程和PRAD的进展。
