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Background: Lung cancer is the most common and deadliest cancer worldwide, and approximately 90% of all lung cancer deaths are caused by tumor metastasis. Tumor-derived exosomes could potentially promote tumor metastasis through the delivery of metastasis-related molecules. However, the function and underlying mechanism of exosomal long noncoding RNA (lncRNA) in lung cancer metastasis remain largely unclear., Methods: Cell exosomes were purified from conditioned media by differential ultracentrifugation and observed using transmission electron microscopy, and the size distributions were determined by nanoparticle tracking analysis. Exosomal lncRNA sequencing (lncRNA-seq) was used to identify long noncoding RNAs. Cell migration and invasion were determined by wound-healing assays, two-chamber transwell invasion assays and cell mobility tracking. Mice orthotopically and subcutaneously xenografted with human cancer cells were used to evaluate tumor metastasis in vivo. Western blot, qRT‒PCR, RNA-seq, and dual-luciferase reporter assays were performed to investigate the potential mechanism. The level of exosomal lncRNA in plasma was examined by qRT‒PCR. MS2-tagged RNA affinity purification (MS2-TRAP) assays were performed to verify lncRNA-bound miRNAs., Results: Exosomes derived from highly metastatic lung cancer cells promoted the migration and invasion of lung cancer cells with low metastatic potential. Using lncRNA-seq, we found that a novel lncRNA, lnc-MLETA1, was upregulated in highly metastatic cells and their secreted exosomes. Overexpression of lnc-MLETA1 augmented cell migration and invasion of lung cancer. Conversely, knockdown of lnc-MLETA1 attenuated the motility and metastasis of lung cancer cells. Interestingly, exosome-transmitted lnc-MLETA1 promoted cell motility and metastasis of lung cancer. Reciprocally, targeting lnc-MLETA1 with an LNA suppressed exosome-induced lung cancer cell motility. Mechanistically, lnc-MLETA1 regulated the expression of EGFR and IGF1R by sponging miR-186-5p and miR-497-5p to facilitate cell motility. The clinical datasets revealed that lnc-MLETA1 is upregulated in tumor tissues and predicts survival in lung cancer patients. Importantly, the levels of exosomal lnc-MLETA1 in plasma were positively correlated with metastasis in lung cancer patients., Conclusions: This study identifies lnc-MLETA1 as a critical exosomal lncRNA that mediates crosstalk in lung cancer cells to promote cancer metastasis and may serve as a prognostic biomarker and potential therapeutic target for lung cancer diagnosis and treatment., (© 2023. Italian National Cancer Institute ‘Regina Elena’.)

Background: Lung cancer has the highest mortality rate in the world, and mounting evidence suggests that cancer stem cells (CSCs) are associated with poor prognosis, recurrence, and metastasis of lung cancer. It is urgent to identify new biomarkers and therapeutic targets for targeting lung CSCs., Methods: We computed the single-sample gene set enrichment analysis (ssGSEA) of 1554 Reactome gene sets to identify the mRNA expression-based stemness index (mRNAsi)-associated pathways using the genome-wide RNA sequencing data of 509 patients from The Cancer Genome Atlas (TCGA) cohort of lung adenocarcinoma (LUAD). Phenotypic effects of ubiquitin-specific peptidase 5 (USP5) on the CSC-like properties and metastasis were examined by in vitro sphere formation assay, migration assay, invasion assay, and in vivo xenografted animal models. Cycloheximide chase assay, co-immunoprecipitation assay, and deubiquitination assay were performed to confirm the effect of USP5 on the deubiquitination of β-catenin., Results: We demonstrated that USP5 expression were positively correlated with the stemness-associated signatures and poor outcomes in lung cancer specimens. Silencing of endogenous USP5 reduced CSC-like characteristics, epithelial-mesenchymal transition (EMT), and metastasis in vitro and in vivo. Furthermore, USP5 interacted with β-catenin, which resulted in deubiquitination, stabilization of β-catenin, and activation of Wnt/β-catenin pathway. Accordingly, expression of USP5 was positively correlated with the enrichment score of the Wnt/TCF pathway signature in human lung cancer. Silencing of β-catenin expression suppressed USP5-enhancing sphere formation. Targeting USP5 with the small molecule WP1130 promoted the degradation of β-catenin, and showed great inhibitory effects on sphere formation, migration, and invasion. Finally, we identified a poor-prognosis subset of tumors characterized by high levels of USP5, Wnt signaling score, and Stemness score in both TCGA-LUAD and Rousseaux_2013 datasets., Conclusions: These findings reveal a clinical evidence for USP5-enhanced Wnt/β-catenin signaling in promoting lung cancer stemness and metastasis, implying that targeting USP5 could provide beneficial effects to improve lung cancer therapeutics., (© 2023. BioMed Central Ltd., part of Springer Nature.)

Background: Lymph node and distant metastasis contribute to poor outcomes in patients with oral squamous cell carcinoma (OSCC). The mechanisms regulating cancer migration and invasion play a key role in OSCC., Methods: We determined migration and invasion ability of OSCC by wound-healing assay, two-chamber transwell invasion assay and cell mobility tracking and evaluated tumor metastasis in vivo. Western blot (WB), qRT-PCR, RNA-seq, dual-luciferase reporter assays and nuclear/cytoplasmic fractionation were performed to investigate the potential mechanism. Immunohistochimical (IHC) staining determined vimentin and PDZK1IP1 expression in OSCC tissues., Results and Conclusion: In this study, we determined that miR-455-5p was associated with lymph node metastasis and clinical invasion, leading to poor outcomes in patients with OSCC. MiR-455-5p promoted oral cancer cell migration and invasion and induced epithelial-to-mesenchymal transition (EMT). We also identified a new biomarker, PDZK1IP1 (MAP17), that was targeted by miR-455-5p. PDZK1IP1 knockdown led to migration, metastasis, EMT, and increased transforming growth factor-β signaling in OSCC. In addition, miR-455-5p overexpression and PDZK1IP1 inhibition promoted collective OSCC cell migration. According to data from the Cancer Genome Atlas database and the NCKU-OrCA-40TN data set, miR-455-5p and PDZK1IP1 are positively and negatively correlated, respectively, with partial EMT score. High miR-455-5p expression was associated with high vimentin levels and low MAP17 H-scores. The patients with low MAP17 expression had higher rates of disease recurrence than did patients with high MAP17 expression, especially for patients with clinical invasion risk factors and low MAP17 expression. These results suggest that miR-455-5p suppresses PDZK1IP1 expression and mediates OSCC progression. MiR-455-5p and PDZK1IP1 may therefore serve as key biomarkers and be involved in regulating partial EMT in OSCC cells. PDZK1IP1 expression may also serve as an independent factor that impacts outcomes in patients with clinical risk factors for recurrence., (© 2023. The Author(s).)

Objective: To investigate the expression of peptidylarginine deiminases (PADIs) during macrophage differentiation and its role in inflammatory responses., Methods: The protein expression of PADI2, PADI4, and citrullinated histone 3 in U937 cells, differentiated macrophages, and macrophages stimulated with lipopolysaccharides (LPS) were analyzed by Western blotting. Three PADI inhibitors were used for assessing their effects on the secretion of proinflammatory cytokines in macrophages. The differential expressed citrullinated proteins during macrophage differentiation were probed by self-prepared anti-citrullinated protein antibodies, and the reactive bands were sent for proteomic analyses. Transfection studies were conducted to search for the functions of specific proteins. A specific protein was cloned and citrullinated for its protein binding study., Results: The expression of PADI2 and PADI4 markedly increased during macrophage differentiation, whereas the formation of citrullinated histone 3 increased after stimulated with lipopolysaccharides. Three PADI inhibitors suppressed the LPS mediated proinflammatory cytokines secretion, but did not affect the expression of PADI2 and PADI4. Plasminogen activator inhibitor-2 (PAI-2) was citrullinated during macrophage differentiation. The expression of PAI-2 increased during macrophage differentiation and further increased after stimulated with LPS. Suppressed PAI-2 expression decreased the expression and secretion of proinflammatory cytokines. Decreased PADI2 expression also suppressed the expression of PAI-2 and protein levels of citrullinated PAI-2. The citrullination of PAI-2 inhibited its binding ability to proteasome subunit beta type-1 (PSMB1)., Conclusion: PADI2 and PADI4 protein levels increased during the macrophage differentiation resulting in protein citrullination, including PAI-2. The increased expression of PAI-2 promoted inflammatory response, and the citrullination of PAI-2 impaired its binding to PSMB1. Therefore, protein citrullination could play a critical role in macrophage differentiation and function.

Background: Interleukin (IL)-23 can facilitate the differentiation of IL-17-producing helper T cells (Th17). The IL-23/IL-17 axis is known to play a key role in the immunopathogenesis of ankylosing spondylitis (AS). We hypothesized that the expression of microRNAs (miRNAs, miRs) would be regulated by IL-23 and that these miRNAs could participate in the immunopathogenesis of AS., Methods: Expression profiles of human miRNAs in K562 cells, cultured in the presence or absence of IL-23 for 3 days, were analyzed by microarray. Potentially aberrantly expressed miRNAs were validated using T-cell samples from 24 patients with AS and 16 control subjects. Next-generation sequencing (NGS) was conducted to search for gene expression and biological functions regulated by specific miRNAs in the IL-23-mediated signaling pathway., Results: Initial analysis revealed that the expression levels of 12 miRNAs were significantly higher, whereas those of 4 miRNAs were significantly lower, in K562 cells after coculture with IL-23 for 3 days. Among these IL-23-regulated miRNAs, the expression levels of miR-29b-1-5p, miR-4449, miR-211-3p, miR-1914-3p, and miR-7114-5p were found to be higher in AS T cells. The transfection of miR-29b-1-5p mimic suppressed IL-23-mediated signal transducer and activator of transcription 3 (STAT3) phosphorylation in K562 cells. After NGS analysis and validation, we found that miR-29b-1-5p upregulated the expression of angiogenin, which was also upregulated in K562 cells after coculture with IL-23. Increased expression of miR-29b-1-5p or miR-211-3p could enhance interferon-γ expression., Conclusions: Among the miRNAs regulated by IL-23, expression levels of five miRNAs were increased in T cells from patients with AS. The transfection of miR-29b-1-5p mimic could inhibit the IL-23-mediated STAT3 phosphorylation and might play a role in negative feedback control in the immunopathogenesis of AS.

Background: Tumor necrosis factor-alpha (TNF-α) can cause diverse T cell dysfunctions in patients with rheumatoid arthritis (RA). It is involved in the regulation of microRNAs (miRNAs) expression in different cell types. We hypothesized that the expression of T cell miRNAs would be affected by TNF-α, and these miRNAs could participate in the immunopathogenesis of RA., Methods: Expression profiles of 270 human miRNAs in Jurkat cells, cultured in the presence or absence of TNF-α for 7 days were analyzed by real-time polymerase chain reaction. Potentially aberrantly expressed miRNAs were validated using T cell samples from 35 patients with RA and 15 controls. Transfection studies were conducted to search for gene expression and biological functions regulated by specific miRNAs., Results: Initial analysis revealed 12 miRNAs were significantly lower, whereas the expression level of miR-146a was significantly higher in Jurkat cells after being cultured with TNF-α for 7 days. Decreased expression of miR-139-3p, miR-204, miR-760, miR-524-5p, miR-136, miR-548d-3p, miR-214, miR-383, and miR-887 were noted in RA T cells. Expression levels of miR-139-3p, miR-204, miR-214, and miR-760 were correlated with the use of biologic agents. The transfection of miR-214 mimic suppressed TNF-α-mediated apoptosis of Jurkat cells. Increased phosphorylation of extracellular regulating kinase (ERK) and c-Jun N-terminal kinase (JNK) was noted in RA T cells and Jurkat cells after TNF-α exposure. Transfection of Jurkat cells with miR-214 mimic suppressed both the basal and TNF-α-mediated ERK and JNK phosphoryation., Conclusions: Among T cell miRNAs affected by TNF-α, the expression levels of nine miRNAs were decreased in T cells from patients with RA. The expression levels of miR-139-3p, miR-204, miR-214, and miR-760 increased in RA patients receiving biologic agents. The transfection of miR-214 reversed the TNF-α-mediated cells apoptosis and inhibited the phosphorylation of ERK and JNK in Jurkat cells.

Background: Overexpression of membranous CD154 in T lymphocytes has been found previously in systemic lupus erythematosus (SLE). Because hydroxychloroquine (HCQ) has been used frequently in the treatment of lupus, we sought to identify the effects of HCQ on CD154 and a possibly regulatory mechanism., Methods: CD4 + T cells were isolated from the blood of lupus patients. After stimulation with ionomycin or IL-15 and various concentrations of HCQ, expression of membranous CD154 and NFAT and STAT5 signaling were assessed., Results: HCQ treatment had significant dose-dependent suppressive effects on membranous CD154 expression in ionomycin-activated T cells from lupus patients. Furthermore, HCQ inhibited intracellular sustained calcium storage release, and attenuated the nuclear translocation of NFATc2 and the expression of NFATc1. However, CD154 expressed through IL-15-mediated STAT5 signaling was not inhibited by HCQ treatment., Conclusions: HCQ inhibited NFAT signaling in activated T cells and blocked the expression of membranous CD154, but not STAT5 signaling. These findings provide a mechanistic insight into SLE in HCQ treatment.

Forkhead box P3 (Foxp3) is the major transcription factor controlling the development and function of regulatory T (Treg) cells. Previous studies have indicated epigenetic regulation of Foxp3 expression. Here, we investigated whether the deoxyribonucleic acid (DNA) methyltransferase inhibitor 5-aza-2'-deoxycytidine (5-Aza) applied peripherally could modulate central nervous system (CNS) inflammation, by using a mouse experimental autoimmune encephalomyelitis (EAE) model. We found that disease activity was inhibited in a myelin oligodendrocyte glycoprotein (MOG) peptide-induced EAE mouse briefly pretreated with low-dose (0.15 mg/kg) 5-Aza, ameliorating significant CNS inflammatory responses, as indicated by greatly decreased proinflammatory cytokines. On the contrary, control EAE mice expressed high levels of IFN-γ and interleukin (IL)-17. In addition, 5-Aza treatment in vitro increased GFP expression in CD4(+)GFP(-) T cells isolated from GFP knock-in Foxp3 transgenic mice. Importantly, 5-Aza treatment increased Treg cell numbers, in EAE mice, at both disease onset and peak. However, Treg inhibition assays showed 5-Aza treatment did not enhance per-cell Treg inhibitory function, but did maintain a lower activation threshold for effector cells in EAE mice. In conclusion, 5-Aza treatment prevented EAE development and suppressed CNS inflammation, by increasing the number of Treg cells and inhibiting effector cells in the periphery.

Background: ParaHox and Hox genes are thought to have evolved from a common ancestral ProtoHox cluster or from tandem duplication prior to the divergence of cnidarians and bilaterians. Similar to Hox clusters, chordate ParaHox genes including Gsx, Xlox, and Cdx, are clustered and their expression exhibits temporal and spatial colinearity. In non-chordate animals, however, studies on the genomic organization of ParaHox genes are limited to only a few animal taxa. Hemichordates, such as the Enteropneust acorn worms, have been used to gain insights into the origins of chordate characters. In this study, we investigated the genomic organization and expression of ParaHox genes in the indirect developing hemichordate acorn worm Ptychodera flava., Results: We found that P. flava contains an intact ParaHox cluster with a similar arrangement to that of chordates. The temporal expression order of the P. flava ParaHox genes is the same as that of the chordate ParaHox genes. During embryogenesis, the spatial expression pattern of PfCdx in the posterior endoderm represents a conserved feature similar to the expression of its orthologs in other animals. On the other hand, PfXlox and PfGsx show a novel expression pattern in the blastopore. Nevertheless, during metamorphosis, PfXlox and PfCdx are expressed in the endoderm in a spatially staggered pattern similar to the situation in chordates., Conclusions: Our study shows that P. flava ParaHox genes, despite forming an intact cluster, exhibit temporal colinearity but lose spatial colinearity during embryogenesis. During metamorphosis, partial spatial colinearity is retained in the transforming larva. These results strongly suggest that intact ParaHox gene clustering was retained in the deuterostome ancestor and is correlated with temporal colinearity.

Background: Increased risk of ischemic stroke has been validated for several cancers, but limited study evaluated this risk in cervical cancer patients. Our study aimed to evaluate the risk of ischemic stroke in cervical cancer patients., Methods: The study analyzed data from the 2003 to 2008 National Health Insurance Research Database (NHIRD) provided by the National Health Research Institutes in Taiwan. Totally, 893 cervical cancer patients after radiotherapy and 1786 appendectomy patients were eligible. The Kaplan-Meier method and the Cox proportional hazards model were used to assess the risk of ischemic stroke., Results: The 5-year cumulative risk of ischemic stroke was significantly higher for the cervical cancer group than for the control group (7.8% vs 5.1%; p <0.005). The risk of stroke was higher in younger (age <51 years) than in older (age ≥51 years) cervical cancer patients (HR = 2.73, p = 0.04; HR = 1.37, p = 0.07) and in patients with more than two comorbid risk factors (5 years cumulative stroke rate of two comorbidities: 15% compared to no comorbidities: 4%)., Conclusions: These study demonstrated cervical cancer patients had a higher risk of ischemic stroke than the general population, especially in younger patients. Strategies to reduce this risk should be assessed.

A recently developed near-infrared fluorescence-labeled folate probe (NIR2-folate) was tested for in vivo imaging of arthritis using a lipopolysaccharide intra-articular injection model and a KRN transgenic mice serum induction mouse model. In the lipopolysaccharide injection model, the fluorescence signal intensity of NIR2-folate (n = 12) and of free NIR2 (n = 5) was compared between lipopolysaccharide-treated and control joints. The fluorescence signal intensity of the NIR2-folate probe at the inflammatory joints was found to be significantly higher than the control normal joints (up to 2.3-fold, P < 0.001). The NIR2-free dye injection group showed a persistent lower enhancement ratio than the NIR2-folate probe injection group. Excessive folic acid was also given to demonstrate a competitive effect with the NIR2-folate. In the KRN serum transfer model (n = 4), NIR2-folate was applied at different time points after serum transfer, and the inflamed joints could be detected as early as 30 hours after arthritogenic antibody transfer (1.8-fold increase in signal intensity). Fluorescence microscopy, histology, and immunohistochemistry validated the optical imaging results. We conclude that in vivo arthritis detection was feasible using a folate-targeted near-infrared fluorescence probe. This receptor-targeted imaging method may facilitate improved arthritis diagnosis and early assessment of the disease progress by providing an in vivo characterization of active macrophage status in inflammatory joint diseases.