RNA N6-methyladenosine (m6A) readers mediate cancer progression. However, the functional role and potential mechanisms of the m6A readers in prostate cancer tumorigenicity remain to be elucidated. In this study, we demonstrate that YTHDF3 expression is elevated in castration-resistant prostate cancer (CRPC) and positively correlated to high grade, bone metastasis and poor survival. YTHDF3 expression promoted CRPC cell proliferation, epithelial to mesenchymal transition (EMT) and tumour progression. Mechanistically, YTHDF3 promoted the RNA degradation of SPOP and NXK3.1 but stabilized RNA expressions of TWIST1 and SNAI2 dependent on m6A to facilitate cell proliferation and EMT. Additionally, YTHDF3 expression enhanced AKT activity via degrading SPOP in an m6A-dependent manner. Importantly, we found that melatonin can compete with m6A to occupy the m6A-binding cage of YTHDF3, leading to inhibition of YTHFD3 and its target expressions as well as CRPC tumour growth. Our findings uncover an essential role of YTHDF3 in the progression of CRPC and highlight the role of melatonin in anti-CRPC activity.

UNASSIGNED: Introduction: Circular RNAs (circRNAs) have been identified as significant contributors to the development and advancement of cancer. The objective of this study was to examine the expression and clinical implications of circRNA circ_BBS9 in lung adenocarcinoma (LUAD), as well as its potential modes of action.
UNASSIGNED: The expression of Circ_BBS9 was examined in tissues and cell lines of LUAD through the utilization of microarray profiling, quantitative real-time polymerase chain reaction (qRT-PCR), and western blot analysis. In this study, we assessed the impact of circ_BBS9 on the proliferation of LUAD cells, as well as its influence on ferroptosis and tumor formation. To analyze these effects, we employed CCK-8 assays and ferroptosis assays. The identification of proteins that interact with Circ_BBS9 was achieved through the utilization of RNA pull-down and mass spectrometry techniques. A putative regulatory network comprising circ_BBS9, miR-7150, and IFIT3 was established using bioinformatics study. The investigation also encompassed the examination of the correlation between the expression of IFIT3 and the invasion of immune cells.
UNASSIGNED: Circ_BBS9 was significantly downregulated in LUAD tissues and cell lines. Low circ_BBS9 expression correlated with poor prognosis. Functional experiments showed that circ_BBS9 overexpression inhibited LUAD cell proliferation and promoted ferroptosis in vitro and suppressed tumor growth in vivo. Mechanistically, circ_BBS9 was found to directly interact with IFIT3 and regulate its expression by acting as a sponge for miR-7150. Additionally, IFIT3 expression correlated positively with immune infiltration in LUAD.
UNASSIGNED: Circ_BBS9 has been identified as a tumor suppressor in lung adenocarcinoma (LUAD) and holds promise as a diagnostic biomarker. The potential mechanism of action involves the modulation of ferroptosis and the immunological microenvironment through direct interaction with IFIT3 and competitive binding to miR-7150. The aforementioned findings offer new perspectives on the pathophysiology of LUAD and highlight circ_BBS9 as a potentially valuable target for therapeutic interventions.

BACKGROUND: Obesity is well-established as a significant contributor to the development of insulin resistance (IR) and diabetes, partially due to elevated plasma saturated free fatty acids like palmitic acid (PA). Grb10-interacting GYF Protein 2 (GIGYF2), an RNA-binding protein, is widely expressed in various tissues including the liver, and has been implicated in diabetes-induced cognitive impairment. Whereas, its role in obesity-related IR remains uninvestigated.
METHODS: In this study, we employed palmitic acid (PA) exposure to establish an in vitro IR model in the human liver cancer cell line HepG2 with high-dose chronic PA treatment. The cells were stained with fluorescent dye 2-NBDG to evaluate cell glucose uptake. The mRNA expression levels of genes were determined by real-time qRT-PCR (RT-qPCR). Western blotting was employed to examine the protein expression levels. The RNA immunoprecipitation (RIP) was used to investigate the binding between protein and mRNA. Lentivirus-mediated gene knockdown and overexpression were employed for gene manipulation. In mice, an IR model induced by a high-fat diet (HFD) was established to validate the role and action mechanisms of GIGYF2 in the modulation of HFD-induced IR in vivo.
RESULTS: In hepatocytes, high levels of PA exposure strongly trigger the occurrence of hepatic IR evidenced by reduced glucose uptake and elevated extracellular glucose content, which is remarkably accompanied by up-regulation of GIGYF2. Silencing GIGYF2 ameliorated PA-induced IR and enhanced glucose uptake. Conversely, GIGYF2 overexpression promoted IR, PTEN upregulation, and AKT inactivation. Additionally, PA-induced hepatic IR caused a notable increase in STAU1, which was prevented by depleting GIGYF2. Notably, silencing STAU1 prevented GIGYF2-induced PTEN upregulation, PI3K/AKT pathway inactivation, and IR. STAU1 was found to stabilize PTEN mRNA by binding to its 3\'UTR. In liver cells, tocopherol treatment inhibits GIGYF2 expression and mitigates PA-induced IR. In the in vivo mice model, GIGYF2 knockdown and tocopherol administration alleviate high-fat diet (HFD)-induced glucose intolerance and IR, along with the suppression of STAU1/PTEN and restoration of PI3K/AKT signaling.
CONCLUSIONS: Our study discloses that GIGYF2 mediates obesity-related IR by disrupting the PI3K/AKT signaling axis through the up-regulation of STAU1/PTEN. Targeting GIGYF2 may offer a potential strategy for treating obesity-related metabolic diseases, including type 2 diabetes.

The unfolded protein response (UPR) is a conserved and adaptive intracellular pathway that relieves the endoplasmic reticulum (ER) stress by activating ER transmembrane stress sensors. As a consequence of ER stress, the inhibition of nonsense-mediated mRNA decay (NMD) is due to an increase in the phosphorylation of eIF2α, which has the effect of inhibiting translation. However, the role of NMD in maintaining ER homeostasis remains unclear. In this study, we found that the three NMD factors, up-frameshift (UPF)1, UPF2, or UPF3B, were required to negate the UPR. Among these three NMD factors, only UPF3B interacted with inositol-requiring enzyme-1α (IRE1α). This interaction inhibited the kinase activity of IRE1α, abolished autophosphorylation, and reduced IRE1α clustering for ER stress. BiP and UPF3B jointly control the activation of IRE1α on both sides of the ER membrane. Under stress conditions, the phosphorylation of UPF3B was increased and the phosphorylated sites were identified. Both the UPF3BY160D genetic mutation and phosphorylation at Thr169 of UPF3B abolished its interaction with IRE1α and UPF2, respectively, leading to activation of ER stress and NMD dysfunction. Our study reveals a key physiological role for UPF3B in the reciprocal regulatory relationship between NMD and ER stress.

BACKGROUND: The modification of N6-methyladenosine (m6A) plays a pivotal role in tumor by altering both innate and adaptive immune systems through various pathways, including the regulation of messenger RNA. The YTH domain protein family, acting as \"readers\" of m6A modifications, affects RNA splicing, stability, and immunogenicity, thereby playing essential roles in immune regulation and antitumor immunity. Despite their significance, the impact of the YTH domain protein family on tumor initiation and progression, as well as their involvement in tumor immune regulation and therapy, remains underexplored and lacks comprehensive review.
CONCLUSIONS: This review introduces the molecular characteristics of the YTH domain protein family and their physiological and pathological roles in biological behavior, emphasizing their mechanisms in regulating immune responses and antitumor immunity. Additionally, the review discusses the roles of the YTH domain protein family in immune-related diseases and tumor resistance, highlighting that abnormal expression or dysfunction of YTH proteins is closely linked to tumor resistance.
CONCLUSIONS: This review provides an in-depth understanding of the YTH domain protein family in immune regulation and antitumor immunity, suggesting new strategies and directions for immunotherapy of related diseases. These insights not only deepen our comprehension of m6A modifications and YTH protein functions but also pave the way for future research and clinical applications.

Preeclampsia (PE) is a life-threatening pregnancy-specific complication with controversial mechanisms and no effective treatment except delivery is available. Currently, increasing researchers suggested that PE shares pathophysiologic features with protein misfolding/aggregation disorders, such as Alzheimer disease (AD). Evidences have proposed defective autophagy as a potential source of protein aggregation in PE. Endoplasmic reticulum-selective autophagy (ER-phagy) plays a critical role in clearing misfolded proteins and maintaining ER homeostasis. However, its roles in the molecular pathology of PE remain unclear. We found that lncRNA DUXAP8 was upregulated in preeclamptic placentae and significantly correlated with clinical indicators. DUXAP8 specifically binds to PCBP2 and inhibits its ubiquitination-mediated degradation, and decreased levels of PCBP2 reversed the activation effect of DUXAP8 overexpression on AKT/mTOR signaling pathway. Function experiments showed that DUXAP8 overexpression inhibited trophoblastic proliferation, migration, and invasion of HTR-8/SVneo and JAR cells. Moreover, pathological accumulation of swollen and lytic ER (endoplasmic reticulum) was observed in DUXAP8-overexpressed HTR8/SVneo cells and PE placental villus trophoblast cells, which suggesting that ER clearance ability is impaired. Further studies found that DUXAP8 overexpression impaired ER-phagy and caused protein aggregation medicated by reduced FAM134B and LC3II expression (key proteins involved in ER-phagy) via activating AKT/mTOR signaling pathway. The increased level of FAM134B significantly reversed the inhibitory effect of DUXAP8 overexpression on the proliferation, migration, and invasion of trophoblasts. In vivo, DUXAP8 overexpression through tail vein injection of adenovirus induced PE-like phenotypes in pregnant rats accompanied with activated AKT/mTOR signaling, decreased expression of FAM134B and LC3-II proteins and increased protein aggregation in placental tissues. Our study reveals the important role of lncRNA DUXAP8 in regulating trophoblast biological behaviors through FAM134B-mediated ER-phagy, providing a new theoretical basis for understanding the pathogenesis of PE.

BACKGROUND: Long noncoding RNAs (lncRNAs) and N6-methyladenosine (m6A) modification of RNA play pivotal roles in tumorigenesis and cancer progression. However, knowledge regarding the expression patterns of m6A-related lncRNAs and their corresponding m6A regulators in prostate cancer (PCa) is limited. This study aimed to delineate the landscape of m6A-related lncRNAs, develop a predictive model, and identify the critical m6A regulators of prognostic lncRNAs in PCa.
METHODS: Clinical and transcriptome data of PCa patients were downloaded from The Cancer Genome Atlas (TCGA) database. Prognostic m6A-related lncRNAs were subsequently identified through Pearson correlation and univariate Cox regression analyses. The prognostic lncRNAs were clustered into two groups by consensus clustering analysis, and a risk signature model was constructed using least absolute shrinkage and selection operator (LASSO) regression analysis of the lncRNAs. This model was evaluated using survival, clinicopathological, and immunological analyses. Furthermore, based on the constructed lncRNA-m6A regulatory network and RT-qPCR results, RBM15 was identified as a critical regulator of m6A-related lncRNAs. The biological roles of RBM15 in PCa were explored through bioinformatics analysis and biological experiments.
RESULTS: Thirty-four prognostic m6A-related lncRNAs were identified and categorized into two clusters with different expression patterns and survival outcomes in PCa patients. Seven m6A lncRNAs (AC105345.1, AL354989.1, AC138028.4, AC022211.1, AC020558.2, AC004076.2, and LINC02666) were selected to construct a risk signature with robust predictive ability for overall survival and were correlated with clinicopathological characteristics and the immune microenvironment of PCa patients. Among them, LINC02666 and AC022211.1 were regulated by RBM15. In addition, RBM15 expression correlated with PCa progression, survival, and the immune response. Patients with elevated RBM15 expression were more susceptible to the drug AMG-232. Moreover, silencing RBM15 decreased the viability of PCa cells and promoted apoptosis.
CONCLUSIONS: RBM15 is involved in the regulation of prognostic lncRNAs in the risk signature and has a robust predictive ability for PCa, making it a promising biomarker in PCa.

Interactions between double-stranded RNA (dsRNA) and proteins play an important role in cellular homeostasis by regulating the editing, stability, and splicing of intracellular RNA. The identification of dsRNA-binding proteins (dsRBPs) is key; however, it has long been challenging to purify dsRBPs from cells. In this study, we developed a novel method, dsRBPC (dsRNA-binding protein capture), to purify cellular dsRBPs based on classic phase separation purification procedures. A global dsRNA-binding proteome of LLC-PK1 cells was obtained, and we identified 1326 dsRBPs, including 1303 putative novel dsRBPs. Functional analyses suggested that these enriched dsRBPs are mainly associated with rRNA processing, RNA splicing, transcriptional regulation, and nucleocytoplasmic transport. We also found that the ARM (armadillo/beta-catenin-like repeats) motif is a previously unknown dsRNA-binding domain, as demonstrated by biochemical experiments. Collectively, this study provides a useful approach for dsRBP identification and the discovery of a global dsRNA-binding proteome to comprehensively map the dsRNA - protein interaction network.

Aortic aneurysm and dissection (AD) represent a critical cardiovascular emergency with an alarmingly high mortality rate. Recent research has spotlighted the overexpression of genes associated with the m6A modification in AD patients, linking them to the presence of inflammatory M1-type macrophages. Moreover, glycolysis is widely recognized as a key feature of inflammatory M1-type macrophages, but biomarkers linking glycolysis and macrophage function to promote disease progression in AD have not been reported. We conducted an analysis of aortic immune cell infiltration, macrophages, and m6A-related biomarkers in AD patients using bioinformatics techniques. Subsequently, we employed a combination of RT-PCR, WB, and immunofluorescence assays to elucidate the alterations in the expression of M1- and M2-type macrophages, as well as markers of glycolysis, following the overexpression of key biomarkers. These findings were further validated in vivo through the creation of a rat model of AD with knockdown of the aforementioned key biomarkers. The findings revealed that the m6A-modified related gene RBM15 exhibited heightened expression in AD samples and was correlated with macrophage polarization. Upon overexpression of RBM15 in macrophages, there was an observed increase in the expression of M1-type macrophage markers CXCL9 and CXCL10, alongside a decrease in the expression of M2-type macrophage markers CCL13 and MRC1. Furthermore, there was an elevation in the expression of glycolytic enzymes GLUT1 and Hexokinase, as well as HIF1α, GAPDH, and PFKFB3 after RBM15 overexpression. Moreover, in vivo knockdown of RBM15 led to an amelioration of aortic aneurysm in the rat AD model. This knockdown also resulted in a reduction of the M1-type macrophage marker iNOS, while significantly increasing the expression of the M2-type macrophage marker CD206. In conclusion, our findings demonstrate that RBM15 upregulates glycolysis in macrophages, thus contributing to the progression of AD through the promotion of M1-type macrophage polarization. Conversely, downregulation of RBM15 suppresses M1-type macrophage polarization, thereby decelerating the advancement of AD. These results unveil potential novel targets for the treatment of AD.

Rationale: Adult neurogenesis in the subventricular zone (SVZ) is essential for maintaining neural homeostasis, and its dysregulation contributes to anosmia and delayed tissue healing in neurological disorders, such as Parkinson\'s disease (PD). Despite intricate regulatory networks identified in SVZ neurogenesis, the molecular mechanisms dynamically maintaining neural stem/progenitor cells (NSPCs) in response to physiological and pathological stimuli remain incompletely elucidated. Methods: We generated an RNA binding motif protein 24 (Rbm24) knockout model to investigate its impact on adult neurogenesis in the SVZ, employing immunofluorescence, immunoblot, electrophysiology, RNA-sequencing, and in vitro experiments. Further investigations utilized a PD mouse model, along with genetic and pharmacological manipulations, to elucidate Rbm24 involvement in PD pathology. Results: Rbm24, a multifaceted post-transcriptional regulator of cellular homeostasis, exhibited broad expression in the SVZ from development to aging. Deletion of Rbm24 significantly impaired NSPC proliferation in the adult SVZ, ultimately resulting in collapsed neurogenesis in the olfactory bulb. Notably, Rbm24 played a specific role in maintaining Notch1 mRNA stability in adult NSPCs. The Rbm24/Notch1 signaling axis was significantly downregulated in the SVZ of PD mice. Remarkably, overexpression of Rbm24 rescued disruption of adult neurogenesis and olfactory dysfunction in PD mice, and these effects were hindered by DAPT, a potent inhibitor of Notch1. Conclusions: Our findings highlight the critical role of the Rbm24/Notch1 signaling axis in regulating adult SVZ neurogenesis under physiological and pathological circumstances. This provides valuable insights into the dynamic regulation of NSPC homeostasis and offers a potential targeted intervention for PD and related neurological disorders.