LRRC75A-AS1 targets miR-199b-5p/PDCD4 axis to repress multiple myeloma

Analysis of the role of dihydromyricetin derived from vine tea (Ampelopsis grossedentata) on multiple myeloma by activating STAT1/RIG-I axis

Multiple myeloma (MM) is a plasma cell malignancy and remains incurable as it lacks effective curative approaches; thus, novel therapeutic strategies are desperately needed. The study aimed to explore the therapeutic role of dihydromyricetin (DHM) in MM and explore its mechanisms. Human MM and normal plasma samples, human MM cell lines, and normal plasma cells were used for in vitro experiments. Cell counting kit-8 (CCK-8), flow cytometry, and trans-well assays were performed for the assessment of cell viability, apoptosis, migration, and invasion, respectively. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to assess the mRNA expression of signal transducer and activator of transcription 1 (STAT1) and retinoic acid-inducible gene I (RIG-I). Western blotting was employed to assess E-cadherin, N-cadherin, signal transducer, STAT1, p-STAT1, and RIG-I protein expression. A tumor xenograft model was used for in vivo experiments. Here, dihydromyricetin (DHM) dose-dependently restrained viability, apoptosis, migration, and invasion, and facilitated apoptosis of U266 cells. After DHM treatment, the E-cadherin level was increased and the N-cadherin level was decreased in U266 and RPMI-8226 cells, suggesting the inhibitory effects of DHM on epithelial-mesenchymal transition (EMT) in MM. Besides, the levels of p-STAT1/STAT1 and RIG-I were down-regulated in MM. However, the STAT1 inhibitor fludarabine undid the suppressive effect of DMH on the malignant characteristics of U266 cells. Also, DHM inhibited MM tumor growth and EMT, and activated STAT1/RIG-I pathway in vivo. Collectively, this study first revealed that DHM can restrain EMT and tumor growth in MM by activating STAT1/RIG-I signaling, which provides a novel drug for the treatment of MM.

Long non-coding RNA small nucleolar RNA host gene 29 drives chronic myeloid leukemia progression via microRNA-483-3p/Casitas B-lineage Lymphoma axis-mediated activation of the phosphoinositide 3-kinase/Akt pathway

The aberrant expression of the long non-coding RNA (lncRNA) Small Nucleolar RNA Host Gene 29 (SNHG29) has been associated with various human cancers. However, the role of SNHG29 in chronic myeloid leukemia (CML) remains elusive. Therefore, this study aimed to investigate the function of SNHG29 in CML and unveil its potential underlying mechanisms. Herein, peripheral blood samples from 44 CML patients and 17 healthy subjects were collected. The expressions of SNHG29, microRNA-483-3p (miR-483-3p), and Casitas B-lineage Lymphoma (CBL) were measured using quantitative polymerase chain reaction (qPCR) or Western Blot. Cell viability, apoptosis, and cell cycle progression were evaluated using the Cell Counting Kit-8 assay, 5-ethynyl-2'-deoxyuridine incorporation, and flow cytometry, respectively. Western Blot analysis was employed to assess protein expressions related to cellular proliferation, apoptosis, and oncogenesis. RNA immunoprecipitation and dual-luciferase reporter assays were utilized to verify the interactions among SNHG29, miR-483-3p, and CBL. SNHG29 was significantly overexpressed in both blood samples of CML patients and CML cell lines. In CML, increased expression of SNHG29 was positively correlated with clinical staging, and patients with high SNHG29 expression had poorer survival outcomes. Functionally, knocking down SNHG29 effectively inhibited CML cell proliferation and promoted apoptosis. Mechanistically, SNHG29 acted as a competing endogenous RNA for miR-483-3p to modulate CBL expression, thereby activating the Phosphoinositide 3-Kinase/Akt signaling pathway and mediating CML progression. In summary, these findings reveal that SNHG29 promotes tumorigenesis in CML, offering a potential therapeutic strategy for CML treatment.

RNA profile of immuno-magnetically enriched lung cancer associated exosomes isolated from clinical samples

Exosomal cargo secreted from cancer cells has been associated with the development and progression of the tumour. Enriching clinically relevant tissue-specific exosomes may assist in the focused analysis of RNA molecules packaged during cancer. Therefore, this study utilized a rapid immunomagnetic enrichment approach for targeted isolation of lung cancer cell-derived exosomes from human plasma, followed by analysing their cargo RNA using high throughput sequencing. The total RNA purified from these immunomagnetically enriched exosomes provided adequate RNA quality for characterization through the Illumina platform. Differential expression analysis was performed between patients and healthy controls to study the altered exosomal RNA profile during lung cancer. Further, functional enrichment analysis was performed with the list of identified differentially expressed genes (DEGs). In total, 1383 mRNAs and 64 lncRNA were identified as differentially expressed between patient plasma exosomes than healthy controls (fold change > 2, P < 0.05). Kyoto encyclopaedia of Genes and Genomes (KEGG) pathway analysis revealed that the DEGs were mainly associated with cancer-related pathways, purine metabolism, calcium, and cGMP-PKG signalling pathways. In conclusion, the presented approach successfully demonstrated a novel strategy for focused disease-specific transcriptome analysis, which provides a feasible option for identifying disease-specific exosome biomarkers for detecting non-small lung cancer.

Yin Yang 1-induced activation of LINC01133 facilitates the progression of pancreatic cancer by sponging miR-199b-5p to upregulate myelin regulatory factor expression

Increasing evidence has reported that long non-coding RNA (lncRNA) plays a vital role in the development of pancreatic cancer (PC). However, the function and mechanism of LINC01133 in PC tumorigenesis are still unknown. Herein, we found that LINC01133 was highly expressed in PC tissues and cell lines, and LINC01133 knockdown could block the growth and metastasis of PC cells. Besides, upregulated LINC01133 in PC cells was induced by Yin Yang 1 (YY1). Furthermore, LINC01133 directly targeted miR-199b-5p and promoted cancer malignancy by suppressing miR-199b-5p. It was also discovered that myelin regulatory factor (MYRF) was targeted by miR-199b-5p and positively correlated with LINC01133 expression in PC, and LINC01133 modulated PC progression through miR-199b-5p/MYRF pathway. In conclusion, we demonstrated that YY1-mediated the upregulation of LINC0113 increased MYRF expression by sponging miR-199b-5p, resulting in the accelerated development of PC. These findings might offer a novel insight into the development of efficient therapeutics for PC patients.

miR-199b-5p-AKAP1-DRP1 pathway plays a key role in ox-LDL-induced mitochondrial fission and endothelial apoptosis

BACKGROUND

Atherosclerosis (AS) remains prevalent despite hyperlipidemia-lowering therapies. Although multiple functions of miR-199b-5p have been implicated in cancers, its role in endothelial apoptosis and AS remains unclear. This study aimed to examine the role of miR-199b-5p in mitochondrial dynamics and endothelial apoptosis.

METHODS

Human umbilical vein endothelial cells (HUVECs) treated with oxidized low-density lipoprotein (ox-LDL) were subjected to other treatments, followed by a series analysis. We found that ox-LDL-treated HUVECs were associated with miR-199b-5p downregulation, increased reactive oxygen species level, reduced adenosine triphosphate (ATP) production, mitochondrial fission, and apoptosis, whereas enhanced miR-199b-5p expression or applied mitochondrial division inhibitor 1 (Mdivi-1) markedly reversed these changes.

RESULTS

Mechanistically, A-kinase anchoring protein 1 (AKAP1) was confirmed as a downstream target of miR-199b-5p by dual-luciferase activity reporter assay, AKAP1 overexpression reversed the anti-apoptotic effects of miR-199b-5p through the enhanced interaction of AKAP1 and dynamin protein 1 (DRP1) in ox-LDL-treated HUVECs. Moreover, miR-199b-5p downregulation, AKAP1 upregulation, and excessive mitochondrial fission were verified in human coronary AS endothelial tissues.

CONCLUSION

The miR-199b-5p-dependent regulation of AKAP1/DRP1 is required to inhibit hyperlipidemia-induced mitochondrial fission and endothelial injury and could be a promising therapeutic target for AS.

Development of an Inflammation-Related lncRNA-miRNA-mRNA Network Based on Competing Endogenous RNA in Breast Cancer at Single-Cell Resolution

The role and mechanism of inflammation in breast cancer is unclear. This study aims to probe the relationship between inflammation and long non-coding RNAs (lncRNAs) and to stablish an inflammation-related competing endogenous RNA (ceRNA) network in breast cancer. Inflammation-related lncRNAs and target genes were screened based on the data from four single-cell RNA sequencing (scRNA-seq) studies and miRNAs were bioinformatically predicted according to ceRNA hypothesis. A series of in silico analyses were performed to construct an inflammation-related ceRNA network in breast cancer. Consequently, a total of seven inflammation-related lncRNAs were selected, after which LRRC75A-AS1 was identified as the most potential lncRNA in view of its expression and prognostic predictive value in breast cancer. Finally, an inflammation-related ceRNA network in breast cancer at the single cell level was established based on lncRNA LRRC75A-AS1, miR-3127-5p, miR-2114-3p, RPL36 and RPL27A mRNAs. Collectively, the lncRNA LRRC75A-AS1 and the LRRC75A-AS1-based on ceRNA network may exert crucial roles in modulating inflammation response during the initiation and progression of breast cancer.

miR-199b-5p mediates adriamycin-induced podocyte apoptosis by inhibiting the expression of RGS10

Podocyte apoptosis is a key risk factor for the progression of kidney diseases. MicroRNA (miR)-199b-5p has been shown to be involved in cell apoptosis. However, the molecular mechanisms of miR-199b-5p in podocyte apoptosis remain uncertain. Thus, the present study aimed to investigate whether miR-199b-5p participates in the regulation of podocyte apoptosis and to elucidate the involved mechanisms of this process. A podocyte apoptosis model was constructed using adriamycin (ADR) in vitro. miR-199b-5p mimic and inhibitor were transfected in podocytes to change the expression level of miR-199b-5p. RNA expression was examined by reverse transcription-quantitative PCR. Western blotting was used to measure protein expression. Apoptosis was monitored via flow cytometry and detection of apoptosis-associated proteins. The results from the present study demonstrated that miR-199b-5p was upregulated and that regulator of G-protein signaling 10 (RGS10) was downregulated in ADR-stimulated podocytes. Overexpression of miR-199b-5p could inhibit RGS10 expression and stimulate podocyte apoptosis, whereas miR-199b-5p knockdown restored the levels of RGS10 and ameliorated podocyte apoptosis in ADR-induced podocytes. Furthermore, the effects of miR-199b-5p overexpression could be significantly reversed by RGS10 overexpression. In addition, podocyte transfection of miR-199b-5p activated the AKT/mechanistic target of rapamycin (mTOR) signaling, which was blocked following RGS10 overexpression. Taken together, the present study demonstrated that miR-199b-5p upregulation could promote podocyte apoptosis by inhibiting the expression of RGS10 through the activation of AKT/mTOR signaling.