Wogonin inhibits the migration and invasion of fibroblast-like synoviocytes by targeting PI3K/AKT/NF-κB pathway in rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is currently an autoimmune inflammatory disease with an unclear pathogenesis. Fibroblast-like synoviocytes (FLSs) have tumor-like properties, and their activation and secretion of pro-inflammatory factors are important factors in joint destruction. Wogonin (5,7-dihydroxy-8-methoxyflavone), a natural flavonoid isolated from Scutellaria baicalensis root, has been shown to have significant anti-inflammatory, anti-oxidative stress, and anti-tumor effects in a variety of diseases. However, the role of wogonin in RA has not yet been demonstrated. PURPOSE: To investigate the inhibitory effect of wogonin on the invasive behavior of fibroblast-like synoviocytes and to explore the mechanism of action of wogonin in RA. METHODS: CCK-8, EdU, cell migration and invasion, immunofluorescence staining, RT-qPCR, and protein blot analysis were used to study the inhibitory effects of wogonin on migration, invasion, and pro-inflammatory cytokine overexpression in the immortalized rheumatoid synovial cell line MH7A. The therapeutic effects of wogonin were validated in vivo using arthritis scores and histopathological evaluation of collagen-induced arthritis mice. RESULTS: Wogonin inhibited the migration and invasion of MH7A cells, reduced the production of TNF-α, IL-1ß, IL-6, MMP-3 and MMP-9, and increased the expression of IL-10. Moreover, wogonin also inhibited the myofibrillar differentiation of MH7A cells, increased the expression of E-cadherin (E-Cad) and decreased the expression of α-smooth muscle actin (α-SMA). In addition, wogonin treatment effectively ameliorated joint destruction in CIA mice. Further molecular mechanism studies showed that wogonin treatment significantly inhibited the activation of PI3K/AKT/NF-κB signaling pathway in TNF-α-induced arthritic FLSs. CONCLUSION: Wogonin effectively inhibits migration, invasion and pro-inflammatory cytokine production of RA fibroblast-like synoviocytes through the PI3K/AKT/NF-κB pathway, and thus wogonin, as a natural flavonoid, has great potential for treating RA.

Peripheral Blood-Derived CircVPS35L as a Potential Diagnostic Biomarker for Non-Small Cell Lung Cancer.

INTRODUCTION: Circular RNAs (circRNAs) are dysregulated in cancers and are stably expressed in body fluids such as blood. We therefore identified and evaluated the clinical value of a newly found circRNA VPS35L (circVPS35L) as a biomarker for the diagnosis of non-small cell lung cancer (NSCLC). METHODS: Reverse-transcription quantitative PCR (RT-qPCR) was used to determine the expression levels of circVPS35L in tissues, whole blood, and cell lines. The actinomycin D assay and RNase R treatment were utilized to determine the stability of circVPS35L. Receiver operating characteristic (ROC) curve analysis was conducted to predict the diagnostic value of blood-derived circVPS35L in NSCLC. RESULTS: CircVPS35L was found to be downregulated in NSCLC tissues and cell lines. Interestingly, circVPS35L expression was significantly correlated with tumor size (p = 0.0269), histology type (p < 0.0001), and TNM stage (p = 0.0437). Importantly, circVPS35L was poorly expressed in peripheral blood of NSCLC patients when compared with healthy controls and patients with benign lung disease. ROC analysis revealed a higher diagnostic value of circVPS35L than the three conventional tumor markers (CYFR21-1, NSE, and CEA) in patients with NSCLC. Moreover, circVPS35L was highly stable in peripheral blood when exposed to undesirable conditions. CONCLUSION: These findings demonstrate that circVPS35L has great potential as a novel biomarker for the diagnosis of NSCLC and can be used to distinguish NSCLC from benign lung disease.

Skp2-Mediated RagA Ubiquitination Elicits a Negative Feedback to Prevent Amino-Acid-Dependent mTORC1 Hyperactivation by Recruiting GATOR1.

The regulation of RagA(GTP) is important for amino-acid-induced mTORC1 activation. Although GATOR1 complex has been identified as a negative regulator for mTORC1 by hydrolyzing RagA(GTP), how GATOR1 is recruited to RagA to attenuate mTORC1 signaling remains unclear. Moreover, how mTORC1 signaling is terminated upon amino acid stimulation is also unknown. We show that the recruitment of GATOR1 to RagA is induced by amino acids in an mTORC1-dependent manner. Skp2 E3 ligase drives K63-linked ubiquitination of RagA, which facilitates GATOR1 recruitment and RagA(GTP) hydrolysis, thereby providing a negative feedback loop to attenuate mTORC1 lysosomal recruitment and prevent mTORC1 hyperactivation. We further demonstrate that Skp2 promotes autophagy but inhibits cell size and cilia growth through RagA ubiquitination and mTORC1 inhibition. We thereby propose a negative feedback whereby Skp2-mediated RagA ubiquitination recruits GATOR1 to restrict mTORC1 signaling upon sustained amino acid stimulation, which serves a critical mechanism to maintain proper cellular functions.

Prostate cancer-associated SPOP mutations lead to genomic instability through disruption of the SPOP-HIPK2 axis.

Speckle-type Poz protein (SPOP), an E3 ubiquitin ligase adaptor, is the most frequently mutated gene in prostate cancer. The SPOP-mutated subtype of prostate cancer shows high genomic instability, but the underlying mechanisms causing this phenotype are still largely unknown. Here, we report that upon DNA damage, SPOP is phosphorylated at Ser119 by the ATM serine/threonine kinase, which potentiates the binding of SPOP to homeodomain-interacting protein kinase 2 (HIPK2), resulting in a nondegradative ubiquitination of HIPK2. This modification subsequently increases the phosphorylation activity of HIPK2 toward HP1γ, and then promotes the dissociation of HP1γ from trimethylated (Lys9) histone H3 (H3K9me3) to initiate DNA damage repair. Moreover, the effect of SPOP on the HIPK2-HP1γ axis is abrogated by prostate cancer-associated SPOP mutations. Our findings provide new insights into the molecular mechanism of SPOP mutations-driven genomic instability in prostate cancer.

lncRNA JPX/miR-33a-5p/Twist1 axis regulates tumorigenesis and metastasis of lung cancer by activating Wnt/ß-catenin signaling.

BACKGROUND: MicroRNAs (miRNAs) and Twist1-induced epithelial-mesenchymal transition (EMT) in cancer cell dissemination are well established, but the involvement of long noncoding RNAs (lncRNAs) in Twist1-mediated signaling remains largely unknown. METHODS: RT-qPCR and western blotting were conducted to detect the expression levels of lncRNA JPX and Twist1 in lung cancer cell lines and tissues. The impact of JPX on Twist1 expression, cell growth, invasion, apoptosis, and in vivo tumor growth were investigated in lung cancer cells by western blotting, rescue experiments, colony formation assay, flow cytometry, and xenograft animal experiment. RESULTS: We observed that lncRNA JPX was upregulated in lung cancer metastatic tissues and was closely correlated with tumor size and an advanced stage. Functionally, JPX promoted lung cancer cell proliferation in vitro and facilitated lung tumor growth in vivo. Additionally, JPX upregulated Twist1 by competitively sponging miR-33a-5p and subsequently induced EMT and lung cancer cell invasion. Interestingly, JPX and Twist1 were coordinately upregulated in lung cancer tissues and cells. Mechanically, the JPX/miR-33a-5p/Twist1 axis participated in EMT progression by activating Wnt/ß-catenin signaling. CONCLUSIONS: These findings suggest that lncRNA JPX, a mediator of Twist1 signaling, could predispose lung cancer cells to metastasis and may serve as a potential target for targeted therapy.

CRISPR/Cas9-mediated noncoding RNA editing in human cancers.

Cancer is characterized by multiple genetic and epigenetic alterations, including a higher prevalence of mutations of oncogenes and/or tumor suppressors. Mounting evidences have shown that noncoding RNAs (ncRNAs) are involved in the epigenetic regulation of cancer genes and their associated pathways. The clustered regularly interspaced short palindromic repeats (CRISPR)-associated nuclease 9 (CRISPR/Cas9) system, a revolutionary genome-editing technology, has shed light on ncRNA-based cancer therapy. Here, we briefly introduce the classifications and mechanisms of CRISPR/Cas9 system. Importantly, we mainly focused on the applications of CRISPR/Cas9 system as a molecular tool for ncRNA (microRNA, long noncoding RNA and circular RNA, etc.) editing in human cancers, and the novel techniques that are based on CRISPR/Cas9 system. Additionally, the off-target effects and the corresponding solutions as well as the challenges toward CRISPR/Cas9 were also evaluated and discussed. Long- and short-ncRNAs have been employed as targets in precision oncology, and CRISPR/Cas9-mediated ncRNA editing may provide an excellent way to cure cancer.

Phosphorylation by mTORC1 stablizes Skp2 and regulates its oncogenic function in gastric cancer.

BACKGROUND: Both mTOR and Skp2 play critical roles in gastric cancer (GC) tumorigenesis. However, potential mechanisms for the association between these two proteins remains unidentified. METHODS: The regulatory role for mTORC1 in Skp2 stability was tested using ubiquitination assay. The functions of p-Skp2 (phosphorylation of Skp2) were studied in vitro and in vivo. Expression of p-Skp2 and p-mTOR (phosphorylation of mTOR) were shown in GC lines and in 169 human primary GC tissues. RESULTS: mTORC1 can directly interact with Skp2 and phosphorylated Skp2 at Ser64, which sequentially protect Skp2 from ubiquitination and degradation. Furthermore, the phospho-deficient p-Skp2 (S64) mutant significantly suppresses GC cell proliferation and tumorigenesis. The expression of p-Skp2 was associated with p-mTOR in GC cell lines and tissues. Interestingly, the combination of p-Skp2 and p-mTOR was a better predictor of survival than either factor alone. CONCLUSION: The mTORC1 function to regulate Skp2 by Ser64 phosphorylation may represent an oncogenic event in GC tumorigenesis. Moreover, our study also indicates that Skp2 Ser64 expression is a potential indicator in the treatment of GC patients using mTORC1 inhibitor.

Long and short noncoding RNAs in lung cancer precision medicine: Opportunities and challenges.

The long and short noncoding RNAs have been involved in the molecular diagnosis, targeted therapy, and predicting prognosis of lung cancer. Utilizing noncoding RNAs as biomarkers and systemic RNA interference as an innovative therapeutic strategy has an immense likelihood to generate novel concepts in precision oncology. Targeting of RNA interference payloads such as small interfering RNAs, microRNA mimetic, or anti-microRNA (antagomirs) into specific cell types has achieved initial success. The clinical trials of noncoding RNA-based therapies are on the way with some positive results. Many attempts are done for developing novel noncoding RNA delivery strategies that could overcome systemic or local barriers. Furthermore, it precipitates concerted efforts to define the molecular subtypes of lung cancer, characterize the genomic landscape of lung cancer subtypes, identify novel therapeutic targets, and reveal mechanisms of sensitivity and resistance to targeted therapies. These efforts contribute a visible effect now in lung cancer precision medicine: patients receive molecular testing to determine whether their tumor harbors an actionable come resistance to the first-generation drugs are in clinical trials, and drugs targeting the immune system are showing activity in patients. This extraordinary promise is tempered by the sobering fact that even the newest treatments for metastatic disease are rarely curative and are effective only in a small fraction of all patients. Thus, ongoing and future efforts to find new vulnerabilities of lung cancers unravel the complexity of drug resistance, increase the efficacy of immunotherapies, and perform biomarker-driven clinical trials are necessary to improve the outcome of lung cancer patients.

[The biological functions and regulations of competing endogenous RNA].

Recent studies demonstrate that RNA species could regulate each other by competing for shared microRNA response elements (MREs). This regulatory model is called competing endogenous RNA (ceRNA). Currently, the identified ceRNAs cover coding and non-coding RNAs. The latter includes pseudogene transcripts, long non-coding RNAs (lncRNAs), circular RNAs (circRNAs) and so on. In this review, we summarize the biological functions of regulatory networks consisting of various types of ceRNAs and their roles in the pathological and physiological processes. Additionally, several factors that may regulate ceRNAs were discussed.

MicroRNAs affect tumor metastasis through regulating epithelial- mesenchymal transition.

Distant metastasis of tumor cell is a series of continuous, selectable cascades of events regulated by multiple factors and genes. Epithelial-mesenchymal transition (EMT) is a critical step during cancer metastasis. However, the mechanism of EMT in tumor is not yet fully elucidated. MicroRNAs (miRNAs) are a class of non-coding small endogenous RNAs that negatively regulate EMT-related genes at the post-transcriptional level and play critical roles in cancer metastasis. This review mainly focuses on the topics that include the relationship of EMT and tumor metastasis, transcription factors involved in EMT, and the effect of miRNAs on tumor metastasis by targeting the EMT-related transcription factors.

MicroRNA-31-5p modulates cell cycle by targeting human mutL homolog 1 in human cancer cells.

MicroRNAs (miRNAs) and DNA mismatch repair (MMR) have been linked to human cancer progression. Human mutL homolog 1 (hMLH1), one of the core MMR genes, defects in lung cancer development. However, the interaction between miRNAs and MMR genes and their regulatory effect on cell cycle remain poorly understood. In this study, we investigated the role of miR-31-5p in hMLH1 gene expression and the effect of miR-31-5p on cell cycle in non-small cell lung cancer (NSCLC). We found that miR-31-5p was inversely correlated with hMLH1 expression in NSCLC cell lines and hMLH1 was a direct target of miR-31-5p. Knockdown of miR-31-5p induced a cell cycle arrest at G2/M phase and increased hMLH1 protein expression in NSCLC cells. Conversely, overexpression of miR-31-5p significantly induced cell cycle arrest at S phase and decreased hMLH1 protein expression. Furthermore, knockdown of hMLH1 upregulated miR-31-5p expression and caused cell cycle arrest at S phase. Data from this study revealed that miR-31-5p modulates cell cycle by targeting hMLH1 protein at the posttranscriptional level in NSCLC, which may represent a novel therapy strategy for lung cancer by targeting miR-31-5p.

Emerging role of long non-coding RNA JPX in malignant processes and potential applications in cancers.

ABSTRACT: Long non-coding RNAs (lncRNAs) reportedly function as important modulators of gene regulation and malignant processes in the development of human cancers. The lncRNA JPX is a novel molecular switch for X chromosome inactivation and differentially expressed JPX has exhibited certain clinical correlations in several cancers. Notably, JPX participates in cancer growth, metastasis, and chemoresistance, by acting as a competing endogenous RNA for microRNA, interacting with proteins, and regulating some specific signaling pathways. Moreover, JPX may serve as a potential biomarker and therapeutic target for the diagnosis, prognosis, and treatment of cancer. The present article summarizes our current understanding of the structure, expression, and function of JPX in malignant cancer processes and discusses its molecular mechanisms and potential applications in cancer biology and medicine.

Kaempferol Attenuates Gouty Arthritis by Regulating the Balance of Th17/Treg Cells and Secretion of IL-17.

Kaempferol is a common flavonoid aglycone widely found in plants. It exhibits beneficial therapeutic effects in the treatment of arthritis. However, the effects of kaempferol on gouty arthritis (GA) have not been verified. This study aimed to explore the potential mechanisms by which kaempferol regulates GA by network pharmacology and experimental validation. Potential drug targets for GA were identified with a protein-protein interaction network. Then, we performed a KEGG pathway analysis to elucidate the major pathway involved in the kaempferol-mediated treatment of GA. In addition, the molecular docking was performed. A rat model of GA was constructed to verify the results of network pharmacology analysis and investigate the mechanism of kaempferol against GA. The network pharmacology study indicated that there were 275 common targets of kaempferol and GA treatment. Kaempferol exerted therapeutic effects on GA, in part, by regulating the IL-17, AGE-RAGE, p53, TNF, and FoxO signaling pathways. Molecular docking results showed that kaempferol stably docked with the core MMP9, ALB, CASP3, TNF, VEGFA, CCL2, CXCL8, AKT1, JUN, and INS. Experimental validation suggested that kaempferol eased MSU-induced mechanical allodynia, ankle edema, and inflammation. It significantly suppressed the expression of IL-1ß, IL-6, TNF-α, and TGF-ß1 and restored Th17/Treg imbalance in MSU-induced rats and IL-6-induced PBMCs. Kaempferol also affected RORγt and Foxp3 through IL-17 pathway. The present study clarifies the mechanism of kaempferol against GA and provides evidence to support its clinical use.

6-Shogaol inhibits the proliferation, apoptosis, and migration of rheumatoid arthritis fibroblast-like synoviocytes via the PI3K/AKT/NF-κB pathway.

BACKGROUND: Fibroblast-like synoviocytes (FLSs) are essential for joint destruction in rheumatoid arthritis (RA). 6-Shogaol, a phenolic extract isolated from ginger, has been found to have potential benefits in the treatment of diverse inflammatory and immune disorders. However, the role of 6-shogaol in RA has yet to be explored. PURPOSE: To reveal the effect of 6-shogaol on RA FLSs and MH7A cells and to investigate the molecular mechanism of 6-shogao in RA. METHODS: We performed MTT, EdU, cell apoptosis, cell migration and invasion, RT-qPCR, western blot analysis, and immunofluorescence to elucidate the effect of 6-shogaol on the proliferation, apoptosis, and migration of RA FLSs and MH7A cells and revealed its modulation of the PI3K/AKT/NF-κB pathway. The in vivo therapeutic effect of 6-shogaol was verified in mice with collagen-induced arthritis (CIA). RESULTS: 6-Shogaol suppressed proliferation, migration, and invasion, and induced apoptosis in RA FLSs and MH7A cells. 6-Shogaol also reduced the production of TNF-α, IL-1ß, IL-6, IL-8, MMP-2, and MMP-9. Molecular analysis revealed that 6-shogaol inhibited the PI3K/AKT/NF-κB pathway by activating PPAR-γ. Treatment with 6-shogaol ameliorated joint destruction of mice with CIA. CONCLUSION: This study revealed that 6-shogaol inhibited proliferation, migration, invasion, cytokine, and MMPs production, and induced apoptosis in RA FLSs via the PI3K/AKT/NF-κB pathway, providing a new natural potential drug for future RA treatments.

Whole Blood-Derived circUSP10 Acts as a Diagnostic Biomarker in Patients With Early-Stage Non-Small-Cell Lung Cancer.

Accumulating evidence has indicated that differentially expressed noncoding circular RNAs (circRNAs) play essential roles in the occurrence and development of various types of cancer. Here, we aimed to identify and explore the diagnostic value of hsa_circ_0003026 (named circUSP10) in patients with early non-small-cell lung cancer (NSCLC). The differentially expressed circRNAs were screened from the microarray-based assay of human NSCLC tissues and their corresponding noncancerous tissues, and the candidate circRNAs were further verified in patients with NSCLC using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Circulating circUSP10 was isolated from whole blood of healthy people and patients with NSCLC and was detected by RT-qPCR. In addition, the diagnostic value of circUSP10 in early NSCLC was evaluated by receiver operating characteristic (ROC) curve analysis. We found that circUSP10 was upregulated in tumor tissues from patients with early NSCLC and associated with tumor size and tumor-node-metastasis (TNM) stage. Importantly, circUSP10 was obviously upregulated in the whole blood of patients with NSCLC. Additionally, whole blood-derived circUSP10 showed good diagnostic performance for screening early NSCLC and was relatively stable in blood under adverse conditions. These findings demonstrate that circUSP10 may act as a novel biomarker for the diagnosis of early-stage NSCLC, suggesting the potential of circUSP10 in RNA-based therapy for cancer.

Cobalt nanoparticles induce mitochondrial damage and ß-amyloid toxicity via the generation of reactive oxygen species.

Exposure to cobalt nanoparticles (CoNPs) has been associated with neurodegenerative disorders, while the mitochondrial-associated mechanisms that mediate their neurotoxicity have yet to be fully characterized. In this study, we reported that CoNPs exposure reduced the survival and lifespan in the nematodes, Caenorhabditis elegans (C. elegans). Moreover, exposure to CoNPs aggravated the induction of paralysis and the aggregation of ß-amyloid (Aß). These effects were accompanied by reactive oxygen species (ROS) overproduction, ATP reduction as well as mitochondrial fragmentation. Dynamin-related protein 1 (drp-1) activation and ensuing mitochondrial fragmentation have been shown to be associated with CoNPs-reduced survival. In order to address the role of mitochondrial damage and ROS production in CoNPs-induced Aß toxicity, the mitochondrial reactive oxygen species scavenger mitoquinone (Mito Q) was used. Our results showed that Mito Q pretreatment alleviated CoNPs-induced ROS generation, rescuing mitochondrial dysfunction, thereby lessening the CoNPs-induced Aß toxicity. Taken together, we show for the first time, that increasing of ROS and the upregulation of drp-1 lead to CoNPs-induced Aß toxicity. Our novel findings provide in vivo evidence for the mechanisms of environmental toxicant-induced Aß toxicity, and can afford new modalities for the prevention and treatment of CoNPs-induced neurodegeneration.

Erratum: SPOP targets oncogenic protein ZBTB3 for destruction to suppress endometrial cancer.

[This corrects the article on p. 2797 in vol. 9, PMID: 31911863.].

MiR-421 is a functional marker of circulating tumor cells in gastric cancer patients.

The detection of circulating tumor cells (CTCs) has recently received great attention. To evaluate if miR-421 could be used as a specific marker for CTCs, the level of miR-421 in mononuclear cells (MNCs) from peripheral blood were determined by reverse transcription-polymerase chain reaction. Transfection of miR-421 inhibitor significantly suppressed tumor growth in vivo. The level of miR-421 in MNCs from gastric cancer was significantly higher than in those from healthy controls. The area under the receiver operating characteristic curve was 0.773 ± 0.0736. In conclusion, miR-421 may be used as a biomarker for monitoring CTCs in patients with gastric cancer.

[Extracellular miRNA: a novel molecular biomarker for lung cancer].

Though continuous development and progress have been made in the early diagnosis and treatment of cancer, it is still difficult to find a sensitive, accurate and minimally invasive biomarker for cancer diagnosis and treatment. MicroRNA (miRNA) is a class of non-coding small endogenous RNAs of 21-24 nucleotides in length. As a novel molecular biomarker, extracellular miRNA (ec-miRNA) has the potential to be a minimally invasive, highly sensitive and highly specific marker in cancer diagnosis. Many research achievements of ec-miRNA have been accumulated in recent years. In this paper, the origin, function and detection of ec-miRNA, its role in lung cancer diagnosis as a novel molecular biomarker, and some issues are reviewed.