Expression Of HNRNPA2B1 Research Articles

Melatonin Regulates Osteoblast Differentiation through the m6A Reader hnRNPA2B1 under Simulated Microgravity.

Recent studies have confirmed that melatonin and N6-methyladenosine (m6A) modification can influence bone cell differentiation and bone formation. Melatonin can also regulate a variety of biological processes through m6A modification. Heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2B1) serves as a reader of m6A modification. In this study, we used the hindlimb unloading model as an animal model of bone loss induced by simulated microgravity and used 2D clinorotation to simulate a microgravity environment for cells on the ground. We found that hnRNPA2B1 was downregulated both in vitro and in vivo during simulated microgravity. Further investigations showed that hnRNPA2B1 could promote osteoblast differentiation and that overexpression of hnRNPA2B1 attenuated the suppression of osteoblast differentiation induced by simulated microgravity. We also discovered that melatonin could promote the expression of hnRNPA2B1 under simulated microgravity. Moreover, we found that promotion of osteoblast differentiation by melatonin was partially dependent on hnRNPA2B1. Therefore, this research revealed, for the first time, the role of the melatonin/hnRNPA2B1 axis in osteoblast differentiation under simulated microgravity. Targeting this axis may be a potential protective strategy against microgravity-induced bone loss and osteoporosis.

HNRNPA2B1 induces cell proliferation and acts as biomarker in breast cancer.

Numerous studies have shown that m6A plays an important regulatory role in the development of tumors. HNRNPA2B1, one of the m6A RNA methylation reading proteins, has been proven to be elevated in human cancers. In this study, we aimed to identify the role of HNRNPA2B1 in breast cancer. HNRNPA2B1 expression was investigated via RT-qPCR and TCGA database in breast cancer. Then, the function of HNRNPA2B1 on cancer cell was measured by CCK8 assays, colony formation and scratch assays. In addition, HNRNPA2B1 expression in BRCA was explored via the Wilcoxon signed-rank test, KruskalWallis test and logistic regression. The association with HNRNPA2B1 expression and survival were considered by KaplanMeier and Cox regression analyses. The biological function of HNRNPA2B1 was analyzed via gene set enrichment analysis (GSEA) and the cluster Profiler R software package. We found that HNRNPA2B1 was highly expressed and induced cell proliferation and migration in breast cancer. Moreover, we observed HNRNPA2B1 induced tumor growth in vivo. In addition, we also found HNRNPA2B1 expression was associated with characteristics and prognosis in breast cancer patients. Our findings suggested that HNRNPA2B1 promoted tumor growth and could function as a new potential molecular marker in breast cancer.

UBE2I regulates the nuclear translocation of hnRNPA2B1 by contributing to SUMO modification in osteoarthritis

BackgroundOsteoarthritis (OA) is a progressive condition affecting the joints that lacking effective therapy. However, the underlying molecular mechanism has not been fully clarified. MethodsA model of OA was established in Sprague-Dawley (SD) rats through intra-articularly injected with monoiodoacetate (MIA). Western blot analysis was used to identify the levels of UBE2I and hnRNPA2B1 in articular cartilage. Overexpression and siRNA vectors for UBE2I were constructed and transfected into rat chondrocytes. CCK-8, TUNEL and transwell assay were utilized to assess the cell viability, apoptosis and migration ability. Western blot analysis was used to determine the levels of chondrogenic-specific genes including SOX9, COL2A1, Aggrecan, and PRG4. Then, molecular interactions were confirmed by immunoprecipitation. ResultsWe observed significant upregulation of UBE2I and hnRNPA2B1 expression in articular cartilage samples of OA. The Pearson correlation analysis revealed positive correlation between UBE2I and hnRNPA2B1 levels. Functional experiments showed that increased UBE2I expression significantly suppressed cell growth, migration, and reduced the expression of chondrogenic-specific genes, while decreasing UBE2I levels had the opposite effects. Molecular interactions between UBE2I and hnRNPA2B1were determined via co-localization and immunoprecipitation. SUMO1 and SUMO3 proteins were enriched by immunoprecipitation using hnRNPA2B1 antibodies. Rescue experiments were performed using SUMOylation inhibitor (2-D08) and SUMOylation activator (N106). Overexpression of UBE2I increased the expression of hnRNPA2B1 in the cytoplasm and decreased the level in the nucleus, which was reversed by the treatment of 2-D08. Conversely, UBE2I knockdown and N106 treatment had the opposite effect. ConclusionsUBE2I modulated the nuclear translocation of hnRNPA2B1 by promoting SUMOylation in OA.

Helicobacter Pylori-Enhanced hnRNPA2B1 Coordinates with PABPC1 to Promote Non-m6A Translation and Gastric Cancer Progression.

Helicobacter pylori (H. pylori) infection is the primary risk factor for the pathogenesis of gastric cancer (GC). N6-methyladenosine (m6A) plays pivotal roles in mRNA metabolism and hnRNPA2B1 as an m6A reader is shown to exert m6A-dependent mRNA stabilization in cancer. This study aims to explore the role of hnRNPA2B1 in H. pylori-associated GC and its novel molecular mechanism. Multiple datasets and tissue microarray are utilized for assessing hnRNPA2B1 expression in response to H. pylori infection and its clinical prognosis in patients with GC. The roles of hnRNPA2B1 are investigated through a variety of techniques including glucose metabolism analysis, m6A-epitranscriptomic microarray, Ribo-seq, polysome profiling, RIP-seq. In addition, hnRNPA2B1 interaction with poly(A) binding protein cytoplasmic 1 (PABPC1) is validated using mass spectrometry and co-IP. These results show that hnRNPA2B1 is upregulated in GC and correlated with poor prognosis. H. pylori infection induces hnRNPA2B1 upregulation through recruiting NF-κB to its promoter. Intriguingly, cytoplasm-anchored hnRNPA2B1 coordinated PABPC1 to stabilize its relationship with cap-binding eIF4F complex, which facilitated the translation of CIP2A, DLAT and GPX1 independent of m6A modification. In summary, hnRNPA2B1 facilitates the non-m6A translation of epigenetic mRNAs in GC progression by interacting with PABPC1-eIF4F complex and predicts poor prognosis for patients with GC.

N6-methyladenosine reader hnRNPA2B1 recognizes and stabilizes NEAT1 to confer chemoresistance in gastric cancer.

Chemoresistance is a major cause of treatment failure in gastric cancer (GC). Heterogeneous nuclear ribonucleoprotein A2B1 (hnRNPA2B1) is an N6-methyladenosine (m6A)-binding protein involved in a variety of cancers. However, whether m6A modification and hnRNPA2B1 play a role in GC chemoresistance is largely unknown. In this study, we aimed to investigate the role of hnRNPA2B1 and the downstream mechanism in GC chemoresistance. The expression of hnRNPA2B1 among public datasets were analyzed and validated by quantitative PCR (qPCR), Western blotting, immunofluorescence, and immunohistochemical staining. The biological functions of hnRNPA2B1 in GC chemoresistance were investigated both in vitro and in vivo. RNA sequencing, methylated RNA immunoprecipitation, RNA immunoprecipitation, and RNA stability assay were performed to assess the association between hnRNPA2B1 and the binding RNA. The role of hnRNPA2B1 in maintenance of GC stemness was evaluated by bioinformatic analysis, qPCR, Western blotting, immunofluorescence, and sphere formation assays. The expression patterns of hnRNPA2B1 and downstream regulators in GC specimens from patients who received adjuvant chemotherapy were analyzed by RNAscope and multiplex immunohistochemistry. Elevated expression of hnRNPA2B1 was found in GC cells and tissues, especially in multidrug-resistant (MDR) GC cell lines. The expression of hnRNPA2B1 was associated with poor outcomes of GC patients, especially in those who received 5-fluorouracil treatment. Silencing hnRNPA2B1 effectively sensitized GC cells to chemotherapy by inhibiting cell proliferation and inducing apoptosis both in vitro and in vivo. Mechanically, hnRNPA2B1 interacted with and stabilized long noncoding RNA NEAT1 in an m6A-dependent manner. Furthermore, hnRNPA2B1 and NEAT1 worked together to enhance the stemness properties of GC cells via Wnt/β-catenin signaling pathway. In clinical specimens from GC patients subjected to chemotherapy, the expression levels of hnRNPA2B1, NEAT1, CD133, and CD44 were markedly elevated in non-responders compared with responders. Our findings indicated that hnRNPA2B1 interacts with and stabilizes lncRNA NEAT1, which contribute to the maintenance of stemness property via Wnt/β-catenin pathway and exacerbate chemoresistance in GC.

Particulate matters 2.5 induce tumor progression in lung cancer by increasing the activity of hnRNPA2B1 resulting in retarding mRNA decay of oxidative phosphorylation.

Particulate matter 2.5 (PM2.5) has been implicated in lung injury and various cancers, yet its precise mechanistic role remains elusive. To elucidate the key signaling pathways underpinning PM2.5-induced lung cancer progression, we embarked on a study examining the impact of PM2.5 both in vitro and in vivo. Lung cancer cell lines, A549 and H157, were employed for the in vitro investigations. Overexpression or knockdown techniques targeting the hnRNPA2B1 protein were implemented. Lung cancer cells were treated with a medium containing PM2.5 and subsequently prepared for in vitro evaluations. Cell growth, invasion, and migration were gauged using transwell and CCK-8 assays. Apoptosis was ascertained through flow cytometry and western blotting of pertinent proteins. Seahorse analyses probed the influence of PM2.5 on lung cancer energy metabolism. The RNA stability assay was employed to discern the impact of PM2.5 on the stability of oxidative phosphorylation-related genes in lung cancer. Our findings revealed that PM2.5 augmented cell proliferation, migration, and invasion rates. Similarly, a diminished apoptosis rate was observed in PM2.5-treated cells. Elevated expression of hnRNPA2B1 was detected in lung cancer cells exposed to PM2.5. Moreover, in cells treated with PM2.5, hnRNPA2B1 knockdown markedly curtailed cell proliferation by inducing G1-S cell cycle arrest and bolstered lung cancer cell apoptosis in vitro; it also curbed xenograft tumor growth. Mechanistically, our data suggest that PM2.5 undermines the stability of mRNA transcripts associated with oxidative phosphorylation (OXPHOS) and augments the formation of processing bodies (P-bodies), leading to an upsurge in OXPHOS levels. In conclusion, PM2.5 appears to drive lung cancer progression and migration by modulating the energy metabolism of lung cancer in a hnRNPA2B1-dependent manner.

LSD1 modulates the bone metastasis of breast cancer cells through hnRNPA2B1-mediated sorting of exosomal miRNAs

Bone metastasis is a key contributor to morbidity and mortality of breast cancer patients. We have previously shown that exosomal miRNAs derived from LSD1 knockdown (KD) breast cancer cells inhibit osteoblast differentiation and promote osteoclast differentiation. However, how LSD1 regulates exosomal miRNAs and whether miRNAs promote bone metastasis through the formation of pre-metastatic niches remains unclear. In vivo experiments demonstrates that exosomes derived from LSD1 KD breast cancer cells significantly promoted bone metastasis. To explore the mechanism underlying the effect of LSD1 on exosomes in breast cancer cells, exosomal and cellular miRNAs from control, LSD1 KD, and rescue cells were sequenced. Interestingly, approximately 80% of LSD1-associated miRNAs were downregulated in exosomes from LSD1 KD cells. The consensus sequence UAGGGC, was identified in many miRNAs downregulated in LSD1 KD exosomes. We found that hnRNPA2B1 regulated the exosomal sorting of miR-6881-3p and some other miRNAs. LSD1 deficiency reduced hnRNPA2B1 expression in breast cancer cells by decreasing the level of H3K9me2 demethylation in the promoter region of the hnRNPA2B1 gene. Our study revealed that LSD1 plays a crucial role in the regulation of exosomal sorting of miRNA.

Ferroptosis, M6A and immune checkpoint-related gene expression in the middle temporal gyrus of the Alzheimer's disease brain

Alzheimer's disease (AD) is a common genetically related cognitive disorder. Studies have shown that ferroptosis, N⁶-Methyladenosine (M6A) and immune checkpoint are related to the development of AD. However, the effects of these three gene pathways on AD progression are still unclear. Here, we used genes expressed in the middle temporal gyrus (MTG) to study the differences in ferroptosis, M6A and immune checkpoint-related gene in 97 Alzheimer's disease and 98 normal controls (NC). We then conducted correlation analysis between ferroptosis, M6A and immune checkpoint-related gene expression levels to investigate the relationship between these genes and AD. Compared to the NC, the gene expression from MTG in AD are as follows: (1) in ferroptosis related genes, the expression of CARS, CDKN1A, HSPB1, MT1G, EMC2, SAT1 and SLC1A5 was increased, while the expression of ACSL4, ATP5MC3, CSID1, CS, DPP4, GLS2 and GPX4 was decreased; (2) in M6A-related genes, the expression of HNRNPA2B1, IGF2BP2, RBM15B and YTHDC1 was increased, while the expression of FTO, YTHDC2 and YTHDF2 was decreased; (3) the expression of immune checkpoint-related genes (including CTLA4, HAVCR2 and LAG3) was increased. Further, we determined related gene pathways among these genes by conducting a literature review. By verifying the dataset, we can well verify our results and prove that our results have good robustness. We concluded of gene expression that a complete set of ferroptosis, M6A and immune checkpoint regulatory mechanisms is activated in the MTG during AD development.

The Potential Impact of HNRNPA2B1 on Human Cancers Prognosis and Immune Microenvironment.

HNRNPA2B1 is a member of the HNRNP family, which is associated with telomere function, mRNA translation, and splicing, and plays an important role in tumor development. To date, there have been no pan-cancer studies of HNRNPA2B1, particularly within the TME. Therefore, we conducted a pan-cancer analysis of HNRNPA2B1 using TCGA data. Based on datasets from TCGA, TARGET, Genotype-Tissue Expression, and Human Protein Atlas, we employed a range of bioinformatics approaches to explore the potential oncogenic role of HNRNPA2B1. This included analyzing the association of HNRNPA2B1 expression with prognosis, tumor mutation burden (TMB), microsatellite instability (MSI), immune response, and immune cell infiltration of individual tumors. We further validated the bioinformatic findings using immunohistochemistry techniques. HNRNPA2B1 was found to be differentially expressed across most tumor types in TCGA's pan-cancer database and was predictive of poorer clinical staging and survival status. HNRNPA2B1 expression was also closely linked to TMB, MSI, tumor stemness, and chemotherapy response. HNRNPA2B1 plays a significant role in the TME and is involved in the regulation of novel immunotherapies. Its expression is significantly associated with the infiltration of macrophages, dendritic cells, NK cells, and T cells. Furthermore, HNRNPA2B1 is closely associated with immune checkpoints, immune-stimulatory genes, immune-inhibitory genes, MHC genes, chemokines, and chemokine receptors. We performed a comprehensive evaluation of HNRNPA2B1, revealing its potential role as a prognostic indicator for patients and its immunomodulatory functions.

Cholesterol homeostasis confers glioma malignancy triggered by hnRNPA2B1-dependent regulation of SREBP2 and LDLR.

Dysregulation of cholesterol metabolism is a significant characteristic of glioma, yet the underlying mechanisms are largely unknown. N6-methyladenosine (m6A) modification has been implicated in promoting tumor development and progression. The aim of this study was to determine the key m6A regulatory proteins involved in the progression of glioma, which is potentially associated with the reprogramming of cholesterol homeostasis. Bioinformatics analysis was performed to determine the association of m6A modification with glioma malignancy from The Cancer Genome Atlas and Genotype-Tissue Expression datasets. Glioma stem cell (GSC) self-renewal was determined by tumor sphere formation and bioluminescence image assay. RNA sequencing and lipidomic analysis were performed for cholesterol homeostasis analysis. RNA immunoprecipitation and luciferase reporter assay were performed to determine hnRNPA2B1-dependent regulation of sterol regulatory element-binding protein 2 (SREBP2) and low-density lipoprotein receptor (LDLR) mRNA. The methylation status of hnRNPA2B1 promoter was determined by bioinformatic analysis and methylation-specific PCR assay. Among the m6A-regulatory proteins, hnRNPA2B1 was demonstrated the most important independent prognostic risk factor for glioma. hnRNPA2B1 ablation exhibited a significant tumor-suppressive effect on glioma cell proliferation, GSC self-renewal and tumorigenesis. hnRNPA2B1 triggers de novo cholesterol synthesis by inducing HMGCR through the stabilization of SREBP2 mRNA. m6A modification of SREBP2 or LDLR mRNA is required for hnRNPA2B1-mediated mRNA stability. The hypomethylation of cg21815882 site on hnRNPA2B1 promoter confers elevated expression of hnRNPA2B1 in glioma tissues. The combination of targeting hnRNPA2B1 and cholesterol metabolism exhibited remarkable antitumor effects, suggesting valuable clinical implications for glioma treatment. hnRNPA2B1 facilitates cholesterol uptake and de novo synthesis, thereby contributing to glioma stemness and malignancy.

Coilin mediates m6A RNA methylation through phosphorylation of METTL3.

MicroRNAs (miRNAs) are a class of noncoding RNAs that regulate gene expression. An important step in miRNA biogenesis occurs when primary miRNAs are bound and cleaved by the microprocessor to generate precursor miRNAs. Regulation at this step is essential and one such regulator includes m6A RNA methylation, an RNA modification found on primary miRNAs that is installed by METTL3 and bound by hnRNPA2B1. Our lab has recently discovered that the Cajal body marker protein coilin also participates in miRNA biogenesis and hypothesized that coilin may be influencing miRNA biogenesis through m6A RNA methylation. Here we report that coilin suppression reduces m6A on primary Let7a and miR-21. We also found that coilin suppression reduced the protein expression of hnRNPA2B1 and METTL3. We observed an interaction between coilin and ectopically expressed METTL3 and found that coilin suppression reduced the nucleoplasmic portion of METTL3 and blunted ectopic METTL3 phosphorylation. Finally, coilin suppression disrupted the greater METTL3 complex with cofactors METTL14 and WTAP. Collectively, our work has uncovered a role for coilin in mediating m6A RNA methylation and provides an avenue by which coilin participates in miRNA biogenesis.

HnRNPA2B1 promotes the occurrence and progression of hepatocellular carcinoma by downregulating PCK1 mRNA via a m6A RNA methylation manner

BackgroundN6-methyladenosine (m6A) is the most prevalent RNA modification. Although hnRNPA2B1, as a reader of m6A modification, has been reported to promote tumorigenesis in a few types of tumors, its role in hepatocellular carcinoma (HCC) and the underlying molecular mechanism remains unclear.MethodsMultiple public databases were used to analyze the expression of hnRNPA2B1 in HCC and its correlation with survival prognosis. We employed a CRISPR-Cas9 sgRNA editing strategy to knockout hnRNPA2B1 expression in HCC cells. The biological function of hnRNPA2B1 in vitro in HCC cells was measured by CCK8, colony formation, migration, and invasion assay. The tumorigenic function of hnRNPA2B1 in vivo was determined by a subcutaneous tumor formation experiment and a HCC mouse model via tail injection of several plasmids into the mouse within 5s-7s. RNA binding protein immunoprecipitation (RIP) experiment using hnRNPA2B1 was performed to test the target genes of hnRNPA2B1 and methylated RNA immunoprecipitation (MeRIP) assay was performed to explore the m6A methylated mRNA of target genes.ResultshnRNPA2B1 highly expressed in HCC tissues, correlated with high grades and poor prognosis. Its knockout reduced HCC cell proliferation, migration, and invasion in vitro, while overexpression promoted these processes. hnRNPA2B1-knockout cells inhibited tumor formation in graft experiments. In HCC mice, endogenous knockout attenuated hepatocarcinogenesis. RNA-seq showed downregulated gluconeogenesis with high hnRNPA2B1 expression. hnRNPA2B1 negatively correlated with PCK1, a key enzyme. RIP assay revealed hnRNPA2B1 binding to PCK1 mRNA. hnRNPA2B1 knockout increased m6A-methylation of PCK1 mRNA. Interestingly, PCK1 knockout partially counteracted tumor inhibition by hnRNPA2B1 knockout in mice.ConclusionOur study indicated that hnRNPA2B1 is highly expressed in HCC and correlated with a poor prognosis. hnRNPA2B1 promotes the tumorigenesis and progression of HCC both in vitro and in vivo. Moreover, hnRNPA2B1 downregulates the expression of PCK1 mRNA via a m6A methylation manner. More importantly, the ability of hnRNPA2B1 to induce tumorigenesis and progression in HCC is dependent on its ability to decrease the expression of PCK1. Therefore, this study suggested that hnRNPA2B1 might be a diagnostic marker of poor prognosis of HCC and a potential therapeutic target for HCC patients.

HNRNPA2B1 is a potential biomarker of breast cancer related to prognosis and immune infiltration.

HNRNPA2B1, one of the regulator of m6A methylation, is involved in a wide range of physiological processes. However, the aberrant expression of HNRNPA2B1 in Breast Cancer (BC) and its clinical significance still need to be further studied. We used related databases to analyze the relationship between HNRNPA2B1 and BC by bioinformatics. Then, we further detected the expression of HNRNPA2B1 by immunohistochemical method, and analyzed the relationship between it and the prognosis of breast cancer by COX regression method. In the study, we found that the expression level of HNRNPA2B1 in breast cancer (BC) was significantly higher than that in normal breast tissues. In addition, the expression level of HNRNPA2B1 in BC samples was significantly correlated with clinical indexes such as TNM stage. The Cox analysis revealed that the expression of HNRNPA2B1 in BC had significant clinical prognostic value. The results of immune infiltration of HNRNPA2B1 showed that there was a significant correlation between HNRNPA2B1 and immune cell subsets. Our results show that the expression of HNRNPA2B1 in BC has important clinical diagnostic significance and high expression may be related with poor clinical outcome of BC. This helps to provide us with a new direction of BC targeted therapy.

LincRNA RP24-315D19.10 promotes endometrial decidualization via upregulation of hnRNPA2B1

Decidualization is a critical process for successful pregnancy. Disorders in this process are tightly associated with adverse pregnancy outcomes including spontaneous abortion. However, the potential molecular mechanisms of lncRNAs underlying this process are yet to be fully elucidated. In this study, we utilized RNA sequencing (RNA-seq) to identify differentially expressed lncRNAs during endometrial decidualization with a pregnant mouse model. Based on RNA-seq analysis, weighted gene co-expression network analysis (WGCNA) was performed to construct the lncRNA-mRNA co-expression network and to identify decidualization-associated hub lncRNAs. Through comprehensive screening and validation, we identified a novel lncRNA, RP24-315D19.10 and studied its function in primary mouse endometrial stromal cells (mESCs). lncRNA RP24-315D19.10 was highly expressed during decidualization. Knockdown of RP24-315D19.10 significantly inhibited mESCs decidualization in vitro. Mechanistically, RNA pull-down and RNA immunoprecipitation assays indicated that cytoplasmic RP24-315D19.10 could bind to hnRNPA2B1, thereby upregulating hnRNPA2B1 expression. Site-directed mutagenesis followed by biolayer interferometry analysis additionally illustrated that hnRNPA2B1 protein specifically bound to the ~-142ccccc~-167 region of the RP24-315D19.10 sequence. hnRPA2B1 deficiency impairs mESCs decidualization in vitro and we found that the inhibition in decidualization caused by RP24-315D19.10 knockdown was rescued by hnRNPA2B1 overexpression. Moreover, the expression of hnRNPA2B1 in spontaneous abortion women with deficient decidualization was significantly lower than that in healthy individuals, suggesting that hnRNPA2B1 may be involved in the development and progression of spontaneous abortion caused by decidualization failure. Collectively, our study indicates RP24-315D19.10 is a critical regulator for endometrial decidualization and RP24-315D19.10-regulated hnRNPA2B1 might be a new mark of decidualization-related spontaneous abortion.

NUF2 promotes tumorigenesis by interacting with HNRNPA2B1 via PI3K/AKT/mTOR pathway in ovarian cancer

BackgroundOvarian cancer (OC) is one of the commonest and deadliest diseases that threaten the health of women worldwide. It is essential to find out its pathogenic mechanisms and therapeutic targets for OC patients. Although NUF2 (Ndc80 kinetochore complex component) has been suggested to play an important role in the development of many cancers, but little is known about its function and the roles of proteins that regulate NUF2 in OC. This study aimed to investigate the effect of NUF2 on the tumorigenicity of OC and the activities of proteins that interact with NUF2.MethodsOncomine database and immunohistochemical (IHC) staining were used to evaluate the expression of NUF2 in OC tissues and normal tissues respectively. Normal ovarian epithelial cell lines (HOSEpiC) and OC cell lines (OVCAR3、HEY、SKOV3) were cultured. Western blot was applied to analyze the expression of NUF2 in these cell lines. Small interfering RNA (siRNA) was used to silence the expression of NUF2 in OC cell lines, SKOV3 and HEY. Gene Set Variation Analysis (GSVA), Gene Set Enrichment Analysis (GSEA), the CCK-8 method, colony formation assay and flow cytometry were conducted to analyze the biological functions of NUF2 in vitro. OC subcutaneous xenograft tumor models were used for in vivo tests. Immunoprecipitation and mass spectrometry (IP/MS) were performed to verify the molecular mechanisms of NUF2 in OC. IP, immunofluorescence, IHC staining, and Gene Expression Profiling Interactive Analysis platform (GEPIA) were used to analyze the relationship between HNRNPA2B1 and NUF2 in OC cells. SiRNA was used to silence the expression of HNRNPA2B1 in SKOV3 cells, reverse transcription quantitative polymerase chain reaction (RT-qPCR) assay and western blot were used to detect the effect of HNRNPA2B1 on NUF2. GEPIA, The Cancer Genome Atlas (TCGA) database, GSEA and western blot were used to detect the potential signaling pathways related to the roles of HNRNPA2B1 and NUF2 in OC cells.ResultsOur results showed high NUF2 expression in OC tissues and OC cell lines, which was associated with shorter overall survival and progression-free survival in patients. NUF2 depletion by siRNA suppressed the proliferation abilities and induced cell apoptosis of OC cells in vitro, and impeded OC growth in vivo. Mechanistically, NUF2 interacted with HNRNPA2B1 and activated the PI3K/AKT/mTOR signaling pathway in OC cells.ConclusionNUF2 could serve as a prognostic biomarker, and regulated the carcinogenesis and progression of OC. Moreover, NUF2 may interact with HNRNPA2B1 by activating the PI3K/AKT/mTOR signaling pathway to promote the development of OC cells. Our present study supported the key role of NUF2 in OC and suggested its potential as a novel therapeutic target.

HNRNPA2B1-mediated m6A modification of TLR4 mRNA promotes progression of multiple myeloma

BackgroundMultiple myeloma (MM) is a malignancy of plasma cells that remains incurable. Toll-like receptor 4 (TLR4) acts as a stress-responsive signal, protecting mitochondria during proteasome inhibitor (PI) exposure, maintaining mitochondrial metabolism and increasing drug resistance in MM. However, the mechanism of TLR4 regulation remains elusive.AimsThe purpose of this study was to investigate the methylation pattern of multiple myeloma and its effect on the expression of HNRNPA2B1 and downstream targets.MethodsThe methylation level in MM and normal bone marrow specimens was detected using a colorimetric assay. HNRNPA2B1 gene knockdown was achieved in RPMI 8226 MM cells via adenovirus transfection. CCK8 and flow cytometric assays were used to detect proliferation and apoptosis, respectively. Transcriptome sequencing and m6A methylation MeRIP sequencing were applied, and differentially expressed genes (DEGs) were detected. Three independent NCBI GEO datasets were applied to examine the effects of HNRNPA2B1 and TLR4 expression on MM patient survival.ResultsHNRNPA2B1 promoted MM progression. Clinical data from database revealed that HNRNPA2B1 was adverse prognostic factor for survival among MM patients. Furthermore, transcriptome sequencing and methylation sequencing showed that HNRNPA2B1 recognized and was enriched at the m6A sites of TLR4 and TLR4 was down-regulated of both the m6A level and transcription level in HNRNPA2B1-knockdown MM cells. Moreover, TLR4 was an adverse survival prognostic factor based on database analysis.ConclusionOverall, our study implies that the RNA-binding protein HNRNPA2B1 increases cell proliferation and deregulates cell apoptosis in MM through TLR4 signaling. Our study suggests HNRNPA2B1 as a potential therapeutic target for MM.

Neddylation-mediated degradation of hnRNPA2B1 contributes to hypertriglyceridemia pancreatitis

Hypertriglyceridemia-induced acute pancreatitis (HTGP) is characterized by the acute and excessive release of FFA produced by pancreatic lipases. However, the underlying mechanisms of this disease remain poorly understood. In this study, we describe the involvement of the RNA binding protein hnRNPA2B1 in the development of HTGP. We used palmitic acid (PA) and AR42J cells to create a model of HTGP in vitro. RT-PCR and western blot analyses revealed a decrease in the level of hnRNPA2B1 protein but not mRNA expression in PA-treated cells. Further analyses revealed that hnRNPA2B1 expression was regulated at the post-translational level by neddylation. Restoration of hnRNPA2B1 expression using the neddylation inhibitor MLN4924 protected AR42J cells from PA-induced inflammatory injury by preventing NF-κB activation and restoring fatty acid oxidation and cell proliferation. Furthermore, RNA immunoprecipitation studies demonstrated that hnRNPA2B1 orchestrates fatty acid oxidation by regulating the expression of the mitochondrial trifunctional protein-α (MTPα). Administration of MLN4924 in vivo restored hnRNPA2B1 protein expression in the pancreas of hyperlipidemic mice and ameliorated HTGP-associated inflammation and pancreatic tissue injury. In conclusion, we show that hnRNPA2B1 has a central regulatory role in preventing HTGP-induced effects on cell metabolism and viability. Furthermore, our findings indicate that pharmacological inhibitors that target neddylation may provide therapeutic benefits to HTGP patients.

Comprehensive analysis of the expression of N6-methyladenosine RNA methylation regulators in pulmonary artery hypertension.

Background: Pulmonary arterial hypertension (PAH) is a progressive disease characterized by pulmonary vascular remodeling. The development of PAH involves N6-methyladenosine (m6A) modification. However, the functional role of m6A regulators in PAH and the underlying regulatory mechanisms remain unknown so far. Methods: Microarray data (GSE149713) for monocrotaline induced PAH (MCT-PAH) rat models were downloaded and screened for differentially expressed genes (DEGs) and m6A regulators. Next, we screened for differentially expressed m6A regulators in endothelial cells (ECs), smooth muscle cells (SMCs), fibroblasts, interstitial macrophages, NK cells, B cells, T cells, regulatory T cells (Tregs) using scRNA sequencing data. The target DEGs of m6A regulators in ECs, SMCs, fibroblasts, and Tregs were functionally annotated using the Gene Ontology (GO) functional analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis. In addition, the cellular interaction analysis was performed to reveal the receptor—ligand pairs regulated by m6A regulators. Pseudo-time trajectory analyses were performed and a ceRNA network of lncRNAs-miRNAs-mRNAs was constructed in SMCs. Furthermore, the RNA transcriptome sequencing data for the SMCs isolated from idiopathic PAH (IPAH) patients (GSE144274) were validated for differentially expressed m6A regulators. Moreover, the HNRNPA2B1 levels in the lung samples from PAH patients and MCT-PAH were determined using immunohistochemistry. Results: The m6A regulators were observed to be dysregulated in PAH. HNRNPA2B1expression level was increased in the PASMCs of scRNAs and IPAH patients. The target DEGs of HNRNPA2B1 were enriched in the regulation of muscle cell differentiation and vasculature development in PASMCs. The HNRNPA2B1 expression levels determined were consistent with the proliferation-related and collagen synthesis-related gene COL4A1. Moreover, the predicted transcription factors (TFs) foxd2/3 and NFκB could be involved in the regulation of HNRNPA2B1. HNRNPA2B1 might be regulating SMCs proliferation and phenotypic transition via rno-miR-330–3p/TGFβR3 and rno-miR-125a-3p/slc39a1. In addition, HNRNPA2B1 was observed to be highly expressed in the lung samples from MCT-PAH rat models and patients with PAH. Conclusion: In summary, the present study identified certain key functional m6A regulators that are involved in pulmonary vascular remodeling. The investigation of m6A patterns might be promising and provide biomarkers for diagnosis and treatment of PAH in the future.

Preclinical Evaluation of hnRNPA2B1 Antibody in Human Triple-Negative Breast Cancer MDA-MB-231 Cells via PET Imaging.

Triple-negative breast cancer (TNBC) does not express estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2. Because TNBC lacks the expression of commonly targeted receptors, it is challenging to develop a new imaging agent for this cancer subtype. Heterogeneous nuclear ribonucleoproteins (hnRNPs) are RNA–protein complexes that have been linked to tumor development and progression. Considering the high expression of hnRNPA2B1, an hnRNP subtype, in TNBC MDA-MB-231 cells, this study aimed to develop a novel hnRNPA2B1 antibody-based nuclear imaging agent. The hnRNPA2B1-specific antibody was radiolabeled with 64Cu and evaluated in vitro and in vivo. The trans-cyclooctene (TCO) was functionalized on the antibody to obtain hnRNP-PEG4-TCO and reactive tetrazine (Tz) on the ultrastable bifunctional chelator PCB-TE2A-alkyne to yield PCB-TE2A-Tz for the inverse electron demand Diels–Alder reaction. The 64Cu-radiolabeled antibody was administered and imaged at 1–18 h time points for conventional imaging. Alternatively, the unlabeled antibody conjugate was administered, and 48 h later radiolabeled 64Cu-PCB-TE2A-Tz was administered to the same mice for the pretargeting strategy and imaged at the same time intervals for direct comparison. The tumor was successfully visualized in both strategies, and comparatively, pretargeting showed superior results. The 64Cu-PCB-TE2A-Tz was successfully clicked at the tumor site with hnRNP-PEG4-TCO and the non-clicked were concurrently eliminated. This led to increase the tumor uptake with extremely high tumor-to-background ratio manifested by positron emission tomography (PET) imaging and biodistribution studies.

Exploiting Interdata Relationships in Prostate Cancer Proteomes: Clinical Significance of HO-1, HSPB1, DDB1 and 14-3-3ζ/δ Interaction

PURPOSE Prostate cancer (PCa) is the second most common type of cancer in men and the sixth leading cause of cancer-related death in men worldwide. The discovery of new therapeutic avenues in PCa, and the development of effective drugs in the era of personalized medicine, would greatly benefit from the field of proteomics. We have previously shown the anti-tumoral role of Heme oxygenase 1 (HO-1) in PCa. METHODS In this work, we undertook a mass spectrometry-based proteomics study to assess whether in PCa cells and under oxidative stress conditions, HO-1 could interact with proteins previously documented to have nuclear localization. RESULTS Among the HO-1 interactors, we identified 11 proteins with nuclear localization. Significant and positive correlation between HMOX1 and six of those genes was observed, using the GSE70770 dataset. Alternatively, HMOX1 and YWHAZ showed negative correlation. High expression of HNRNPA2B1, HSPB1, NPM1, DDB1, HMGA1, ZC3HAV1, and HMOX1 was associated with an increased relapse-free survival (RFS) in PCa patients through univariable analyses. Further, PCa patients with high HSPB1/HMOX1, DDB1/HMOX1, and YWHAZ/HMOX1 showed a worse RFS compared with patients with lower ratios. Moreover, by using a prognostic risk score model, a decrease in RFS for patients with higher scores of this signature was observed. However, the only factor significantly associated with a higher risk of relapse was high YWHAZ. HSPB1, DDB1 and YWHAZ independence from PCa clinic-pathological parameters was confirmed through multivariable analyses. Moreover, co-immunoprecipitation analysis in PCa cells ascertained HO-1/14-3-3ζ/δ (YWHAZ encoding gene) interaction. CONCLUSION Herein, we report novel interactions between HO-1 and HSPB1, DDB1 and 14-3-3ζ/δ, highlighting their clinical relevance in PCa.