OBJECTIVE: Non-alcoholic fatty liver disease (NAFLD) involves hepatic accumulation of intracellular lipid droplets via incompletely understood processes. Here, we report distinct and cooperative NAFLD roles of LysTTT-5\'tRF transfer RNA fragments and microRNA miR-194-5p.
METHODS: Combined use of diet induced obese mice with human-derived oleic acid-exposed Hep G2 cells revealed new NAFLD roles of LysTTT-5\'tRF and miR-194-5p.
RESULTS: Unlike lean animals, dietary-induced NAFLD mice showed concurrent hepatic decrease of both LysTTT-5\'tRF and miR-194-5p levels, which were restored following miR-132 antisense oligonucleotide treatment which suppresses hepatic steatosis. Moreover, exposing human-derived Hep G2 cells to oleic acid for 7 days co-suppressed miR-194-5p and LysTTT-5\'tRF levels while increasing lipid accumulation. Inversely, transfecting fattened cells with a synthetic LysTTT-5\'tRF mimic elevated mRNA levels of the metabolic regulator β-Klotho while decreasing triglyceride amounts by 30% within 24 h. In contradistinction, antisense suppression of miR-194-5p induced accumulation of its novel target, the NAFLD-implicated lipid droplet-coating PLIN2 protein. Further, two out of 15 steatosis-alleviating screened drug-repurposing compounds, Danazol and Latanoprost, elevated miR-194-5p or LysTTT-5\'tRF levels.
CONCLUSIONS: Our findings highlight the different yet complementary roles of miR-194-5p and LysTTT-5\'tRF and offer new insights into the complex roles of small non-coding RNAs and the multiple pathways involved in NAFLD pathogenesis.

UNASSIGNED: To investigate the possible molecular mechanism of miR-194-5p/PRC1/Wnt/β-catenin signaling axis that regulates the invasive metastatic ability and radiotherapy sensitivity of esophageal squamous cell carcinoma (ESCC) cells.
UNASSIGNED: ESCC-related differentially expressed miRNAs were identified by microarray analysis, followed by the identification of a putative target. The targeting relationship between miR-194-5p and PRC1 was assayed. A series of mimic and shRNA were transfected into ESCC cells to find out the mechanism of miR-194-5p in ESCC by regulating PRC1 through Wnt/β-catenin signaling pathway and their effect on cell proliferation, migration, invasion, and radiosensitivity as well as xenograft tumor growth and metastasis in nude mice.
UNASSIGNED: We demonstrated low miR-194-5p expression and high PRC1 expression in ESCC tissues and cells. PRC1 was confirmed as a putative target for miR-194-5p. High miR-194-5p or silenced PRC1 enhanced ESCC cell radiosensitivity but reduced proliferation, invasion, and migration via PRC1 through modulation of the Wnt/β-catenin signaling pathway. Animal experiments also validated that overexpression of miR-194-5p suppressed tumorigenesis and in vivo metastasis in nude mice.Conclusion: miR-194-5p can inhibit the Wnt/β-catenin signaling pathway through down-regulation of the PRC1 gene, thereby enhancing the sensitivity of ESCC cells to radiotherapy and attenuating the invasion and metastasis ability of ESCC cells.

Among breast cancer (BC) subtypes, the most aggressive is triple negative BC (TNBC), which is prone to metastasis. We previously found that microRNA (miR)-194-5p is downregulated at the early stages of TNBC brain metastasis development. Additionally, the transcription factor myocyte enhancer factor 2 (MEF2)C, a bioinformatically predicted miR-194-5p target, was increasingly expressed throughout TNBC brain metastasis formation and disease severity. However, the contributions of these two players to malignant cells\' features remain undetermined. This study aimed at disclosing the role of miR-194-5p and MEF2C in TNBC tumorigenesis. The transfection of 4T1 cells with a silencer for MEF2C or with a pre-miRNA for miR-194-5p was employed to study TNBC cells\' phenotypic alterations regarding epithelial and mesenchymal markers, as well as migratory capability alterations. MEF2C-silenced cells presented a decline in both vimentin and cytokeratin expression, whereas the overexpression of miR-194-5p promoted an increase in cytokeratin and a reduction in vimentin, reflecting the acquisition of an epithelial phenotype. Both treatments reduced TNBC cells\' migration. These results suggest that MEF2C may determine TNBC cells\' invasive properties by partially determining the occurrence of epithelial-mesenchymal transition, while the overexpression of miR-194-5p promotes a decline in TNBC cells\' aggressive behavior and reinforces this miRNA\'s role as a tumor suppressor in TNBC.

Prostate cancer (PCa) is the most common cause of cancer death among African men. The analysis of microRNAs (miRNAs) in plasma extracellular vesicles (EVs) can be utilized as a non-invasive tool for the diagnosis of PCa. In this study, we used small RNA sequencing to profile miRNAs cargo in plasma EVs from South African PCa patients. We evaluated the differential expression of miRNAs between low and high Gleason scores in the plasma EVs of South African patients and in the prostatic tissue from data available in the Cancer Genome Atlas (TCGA) Data Portal. We identified 7 miRNAs differently expressed in both EVs and prostatic tissues. We evaluated their expression using qPCR in a larger cohort of 10 patients with benign prostatic hyperplasia (BPH) and 24 patients with PCa. Here, we reported that the ratio between two of these miRNAs (i.e., miR-194-5p/miR-16-5p) showed a higher concentration in PCa compared to BPH and in metastatic PCa compared to localized PCa. We explored for the first time the profiling of miRNAs cargo in plasma EVs as a tool for the identification of putative markers in the South African population. Our finding indicated the ratio miR-194-5p/miR-16-5p as a non-invasive marker for the evaluation of PCa aggressiveness in this population.

Diabetic kidney disease (DKD) is the most prevalent chronic kidney disease. Macrophage infiltration in the kidney is critical for the progression of DKD. However, the underlying mechanism is far from clear. Cullin 4B (CUL4B) is the scaffold protein in CUL4B-RING E3 ligase complexes. Previous studies have shown that depletion of CUL4B in macrophages aggravates lipopolysaccharide-induced peritonitis and septic shock. In this study, using two mouse models for DKD, we demonstrate that myeloid deficiency of CUL4B alleviates diabetes-induced renal injury and fibrosis. In vivo and in vitro analyses reveal that loss of CUL4B suppresses migration, adhesion, and renal infiltration of macrophages. Mechanistically, we show that high glucose upregulates CUL4B in macrophages. CUL4B represses expression of miR-194-5p, which leads to elevated integrin α9 (ITGA9), promoting migration and adhesion. Our study suggests the CUL4B/miR-194-5p/ITGA9 axis as an important regulator for macrophage infiltration in diabetic kidneys.

Stroke is an acute cerebrovascular disease that is now the most important cause of death due to brain problems in our country. CircRNAs are RNA circles that have been extensively involved in the disease. We aimed to investigate the mechanism of circ_0129657 in the pathogenesis of stroke. In this study, quantitative real-time polymerase chain reaction (RT-qPCR) and western blot assays were used to assess the expression of circ_0129657, miR-194-5p, and glia maturation factor beta (GMFB). Cell viability was measured by Cell Counting Kit-8 (CCK-8) assay. 5-Ethynyl-2\'-Deoxyuridine (EdU) assay was used to detect cell proliferation. Flow cytometry was used to detect cell apoptosis. Dual-luciferase reporter, RNA pull-down, and RNA immunoprecipitation (RIP) assays were used to assess the relationship between miR-194-5p and circ_0129657 or GMFB. Mouse middle cerebral artery occlusion (MCAO) model was applied to mimic the cerebral ischemia/reperfusion injury. Our data showed that the levels of circ_0129657 and GMFB were significantly increased and the expression of miR-194-5p was significantly decreased in oxygen-glucose deprivation (OGD)-induced human brain microvascular endothelial cells (HBMECs). Silencing circ_0129657 expression in OGD-induced HBMECs could promote cell viability and cell proliferation. Moreover, circ_0129657 depletion also could inhibit apoptosis and inflammatory factor secretion. Circ_0129657 functioned as a sponge for miR-194-5p and could regulate GMFB expression via miR-194-5p competition. Furthermore, miR-194-5p downregulation or GMFB restoration could partially reverse the effects of circ_0129657 silencing on cell biological properties in OGD-induced HBMECs. Meanwhile, circ_0129657 knockdown decreased cerebral infarction volume and neurological impairment in MCAO mouse models. In conclusion, our findings suggest that circ_0129657 can inhibit cell proliferation and promote apoptosis and inflammatory factor secretion in HBMECs after oxygen-glucose deprivation via miR-194-5p/GMFB axis, providing evidence that circ_0129657 has the potential as a useful biological molecular marker in the diagnosis of stroke.

Osteosarcoma (OS) is the most common bone tumour with a high risk of metastatic progression and recurrence after treatment. Circular RNA hsa_circ_0000591 (circ_0000591) plays a compelling role in OS aggressiveness. However, the function and regulatory mechanism of circ_0000591 need to be further elucidated. As a subject of this study, a differential circRNA circ_0000591 was screened by circRNA microarray expression profiling (GSE96964). Expression changes of circ_0000591 were detected using real-time quantitative polymerase chain reaction (RT-qPCR). Effects of circ_0000591 silencing on OS cell viability, proliferation, colony formation, apoptosis, invasion, and glycolysis were determined via functional experiments. The mechanism by which circ_0000591 functions as a molecular sponge for miRNAs was predicted using bioinformatics analysis and validated using dual-luciferase reporter and RNA pull-down assays. Xenograft assay was done to validate the function of circ_0000591. Circ_0000591 was strongly expressed in OS samples and cells. Silencing of circ_0000591 lessened cell viability, repressed cell proliferation, invasion, glycolysis, and promoted cell apoptosis. Importantly, circ_0000591 regulated HK2 expression by serving as a miR-194-5p molecular sponge. MiR-194-5p silencing impaired circ_0000591 downregulation-mediated suppression of OS cell malignancy and glycolysis. HK2 overexpression weakened the inhibiting impacts of miR-194-5p on OS cell malignancy and glycolysis. Also, circ_0000591 silencing decreased xenograft tumour growth in vivo. Circ_0000591 drove OS glycolysis and growth by upregulating HK2 by sequestering miR-194-5p. The study highlighted the tumour-promoting function of circ_0000591 in OS.

UNASSIGNED: The absence of breast cancer cells in surgical specimens, i.e., pathological complete response (pCR), is widely recognized as a favorable prognostic factor after neoadjuvant therapy. In contrast, the presence of disease at surgery characterizes a prognostically heterogeneous group of patients. Here, we challenged circulating microRNAs (miRNAs) at the end of neoadjuvant therapy as potential prognostic biomarkers in the NeoALTTO study.
UNASSIGNED: Patients treated within the trastuzumab arm (i.e., pre-operative weekly trastuzumab for 6 weeks followed by the addition of weekly paclitaxel for 12 weeks; post-operative FEC for 3 cycles followed by trastuzumab up to complete 1 year of treatment) were randomized into a training (n= 54) and testing (n= 72) set. RT-PCR-based high-throughput miRNA profile was performed on plasma samples collected at the end of neoadjuvant treatment of both sets. After normalization, circulating miRNAs associated with event free survival (EFS) were identified by univariate and multivariate Cox regression model.
UNASSIGNED: Starting from 23 circulating miRNAs associated with EFS in the training set, we generated a 3-circulating miRNA prognostic signature consisting of miR-185-5p, miR-146a-5p, miR-22-3p, which was confirmed in the testing set. The 3-circulating miRNA signature showed a C-statistic of 0.62 (95% confidence interval [95%CI] 0.53-0.71) in the entire study cohort. By resorting to a multivariate Cox regression model we found a statistical significant interaction between the expression values of miR-194-5p and pCR status (p.interaction =0.005) with an estimate Hazard Ratio (HR) of 1.83 (95%CI 1.14- 2.95) in patients with pCR, and 0.87 (95%CI 0.69-1.10) in those without pCR. Notably, the model including this interaction along with the abovementioned 3-circulating miRNA signature provided the highest discriminatory capability with a C-statistic of 0.67 (95%CI 0.58-0.76).
UNASSIGNED: Circulating miRNAs are informative to identify patients with different prognosis among those with heterogeneous response after trastuzumab-based neoadjuvant treatment, and may be an exploitable tool to select candidates for salvage adjuvant therapy.

Oral squamous cell carcinoma (OSCC) is a common malignant tumor with high recurrence, metastasis rates, and poor prognosis. Numerous studies discover that circular RNA (circRNA) is closely associated with OSCC progression. Hsa_circ_0020377 has been aberrantly expressed in OSCC, but its role in tumor growth and metastasis remains largely unclear. Hsa_circ_0020377, microRNA-194-5p (miR-194-5p), and Krüppel-like factor 7 (KLF7) contents were determined by real-time quantitative polymerase chain reaction (RT-qPCR). Cell proliferative, cycle progression migration, and invasion were measured using 5-ethynyl-2\'-deoxyuridine (EdU), Cell Counting Kit-8 (CCK-8), flow cytometry, wound healing, and Transwell assays. The glycolysis level was detected via specific kits. Cyclin D1, E-cadherin, hexokinase 2 (HK2), and KLF7 protein levels were detected via western blot. Using predicting bioinformatics software, the binding between miR-194-5p and hsa_circ_0020377 or KLF7 was verified using a dual-luciferase reporter and RNA Immunoprecipitation (RIP). Beyond that, a xenograft tumor model was used to analyze the role of hsa_circ_0020377 on tumor cell growth in vivo. Increased hsa_circ_0020377 and KLF7 and reduced miR-194-5p were found in OSCC tissues and cell lines. Loss-of-function experiments proved that hsa_circ_0020377 depletion might block OSCC cell proliferation, cycle progression, migration, invasion, and glycolysis in vitro. In xenograft mouse models, hsa_circ_0020377 silencing might suppress tumor growth. In addition, mechanism research suggested that hsa_circ_0020377 could bind with miR-194-5p and enhance its target gene (KLF7), thereby affecting OSCC development. These results broaden our insights regarding the regulation of OSCC progression via circRNA and act as a reference for future clinical studies in OSCC diagnosis and treatment.

Temporal lobe epilepsy (TLE) leads to extensive degradation of the quality of life of patients. Glycyrrhizic acid (GA) has been reported to exert neuroprotective effects on status epilepticus. Herein, the current study set out to explore the functional mechanism of GA in TLE young rats. Firstly, TLE young rat models were established using the lithium chloride and pilocarpine regimen and then subjected to treatment with different doses of GA, miR-194-5p-antagomir, or/and sh-prostaglandin-endoperoxide synthase 2 (PTGS2) to observe changes in iron content, glutathione and malondialdehyde levels, and GPX4 (glutathione peroxidase 4) and PTGS2 protein levels in the hippocampus. Neuronal injury and apoptosis were assessed through HE, Nissl, and TUNEL staining. Additionally, the expression patterns of miR-194-5p were detected. The binding site of miR-194-5p and PTGS2 was verified with a dual-luciferase assay. Briefly, different doses of GA (20, 40, and 60 mg/kg) reduced the epileptic score, frequency, and duration in TLE young rats, along with reductions in iron content, lipid peroxidation, neuronal injury, and apoptosis in the hippocampus. Silencing of miR-194-5p partly annulled the action of GA on inhibiting ferroptosis and attenuating neuronal injury in TLE young rats. Additionally, PTGS2 was validated as a target of miR-194-5p. GA inhibited ferroptosis and ameliorated neuronal injury in TLE young rats via the miR-194-5p/PTGS2 axis. Overall, our findings indicated that GA exerts protective effects on TLE young rats against neuronal injury by inhibiting ferroptosis through the miR-194-5p/PTGS2 axis.