Epigenetic silencing of miR-335 induces migration by targeting insulin-like growth factor-1 receptor in multiple myeloma

Circ_0005615 restrains the progression of multiple myeloma through modulating miR-331-3p and IGF1R regulatory cascade

BACKGROUND

Circular RNAs are implicated in modulating the progression of various malignant tumors. However, the function and underlying mechanisms of circ_0005615 in multiple myeloma (MM) remain unclear.

METHODS

The expression levels of circ_0005615, miR-331-3p and IGF1R were tested by quantitative real-time polymerase chain reaction or western blot assay. Cell counting kit-8 and 5-ethynyl-2'-deoxyuridine (EdU) assay were performed for cell proliferation detection. Cell apoptosis and cell cycle were measured by flow cytometry. The protein expressions of Bax and Bcl-2 were detected by western blot assay. Glucose consumption, lactate production and ATP/ADP ratios were estimated to disclose cell glycolysis. The interaction relationship among miR-331-3p and circ_0005615 or IGF1R was proved by dual-luciferase reporter assay.

RESULTS

The abundance of circ_0005615 and IGF1R was increased in MM patients and cells, while the expression of miR-331-3p was decreased. Circ_0005615 inhibition retarded the proliferation and cell cycle progression, while reinforced the apoptosis of MM cells. Molecularly, circ_0005615 could sponge miR-331-3p, and the repressive trends of circ_0005615 deficiency on MM progression could be alleviated by anti-miR-331-3p introduction. Additionally, IGF1R was validated to be targeted by miR-331-3p, and IGF1R overexpression mitigated the suppressive function of miR-331-3p on MM development. Furthermore, IGF1R was mediated by circ_0005615/miR-331-3p axis in MM cells.

CONCLUSION

Circ_0005615 downregulation blocked MM development by targeting miR-331-3p/IGF1R axis.

A Novel Small Molecular Inhibitor of DNMT1 Enhances the Antitumor Effect of Radiofrequency Ablation in Lung Squamous Cell Carcinoma Cells

Radiofrequency ablation (RFA) is a relatively new and effective therapeutic strategy for treating lung squamous cell carcinomas (LSCCs). However, RFA is rarely used in the clinic for LSCC which still suffers from a lack of effective comprehensive treatment strategies. In the present work, we investigate iDNMT, a novel small molecular inhibitor of DNMT1 with a unique structure. In clinical LSCC specimens, endogenous DNMT1 was positively associated with methylation rates of miR-27-3p's promoter. Moreover, endogenous DNMT1 was negatively correlated with miR-27-3p expression which targets PSEN-1, the catalytic subunit of γ-secretase, which mediates the cleavage and activation of the Notch pathway. We found that DNMT1 increased activation of the Notch pathway in clinical LSCC samples while downregulating miR-27-3p expression and hypermethylation of miR-27-3p's promoter. In addition of inhibiting activation of the Notch pathway by repressing methylation of the miR-27-3p promoter, treatment of LSCC cells with iDNMT1 also enhanced the sensitivity of LSCC tumor tissues to RFA treatment. These data suggest that iDNMT-induced inhibition of DNMT-1 enhances miR-27-3p expression in LSCC to inhibit activation of the Notch pathway. Furthermore, the combination of iDNMT and RFA may be a promising therapeutic strategy for LSCC.

Homo sapiens circular RNA 0003602 (Hsa_circ_0003602) accelerates the tumorigenicity of acute myeloid leukemia by modulating miR-502-5p/IGF1R axis

Acute myeloid leukemia (AML) has become a worldwide malignant cancer. We intended to investigate the critical roles and mechanism underlying homo sapiens circular RNA 0003602 (hsa_circ_0003602) in AML progression, especially in tumor cell proliferation, migration, invasion, and apoptosis. Real-time PCR was applied to identify the differential expression of hsa_circ_0003602 and miR-502-5p in AML bone marrow tissues and cell lines. In addition, western blot analysis was employed to determine the levels insulin-like growth factor 1 receptor (IGF1R) protein. The biological behaviors were assessed by CCK-8 cell viability assay, flow cytometry assay for apoptosis detection, and Transwell migration and invasion assay. The relationships between target miRNA and downstream mRNA were investigated by bioinformatics, luciferase reporter assay, and biotin-labeled RNA pull-down assay. Hsa_circ_0003602 was upregulated and predicted poor survival in AML. Knockdown of hsa_circ_0003602 in AML cell lines induced the inhibition of proliferation, migration, and invasion and caused apoptosis. Hsa_circ_0003602 sequestered miR-502-5p by functioning as a competitive endogenous RNA (ceRNA), thereby regulating IGF1R expression. Hsa_circ_0003602 acted as a tumor promoter in AML via miR-502-5p/IGF1R axis. Our study provides evidence that hsa_circ_0003602, miR-502-5p, and IGF1R might form a regulatory axis to affect the carcinogenicity of AML cells and provide potential targets for the treatment of AML.

Downregulation of miR-335 exhibited an oncogenic effect via promoting KDM3A/YAP1 networks in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common type of renal cancer affecting many people worldwide. Although the 5-year survival rate is 65% in localized disease, after metastasis, the survival rate is <10%. Emerging evidence has shown that microRNAs (miRNAs) play a crucial regulatory role in the progression of ccRCC. Here, we show that miR-335, an anti-onco-miRNA, is downregulation in tumor tissue and inhibited ccRCC cell proliferation, invasion, and migration. Our studies further identify the H3K9me1/2 histone demethylase KDM3A as a new miR-335-regulated gene. We show that KDM3A is overexpressed in ccRCC, and its upregulation contributes to the carcinogenesis and metastasis of ccRCC. Moreover, with the overexpression of KDM3A, YAP1 was increased and identified as a direct downstream target of KDM3A. Enrichment of KDM3A demethylase on YAP1 promoter was confirmed by CHIP-qPCR and YAP1 was also found involved in the cell growth and metastasis inhibitory of miR-335. Together, our study establishes a new miR-335/KDM3A/YAP1 regulation axis, which provided new insight and potential targeting of the metastasized ccRCC.

A Molecular Signature of Circulating MicroRNA Can Predict Osteolytic Bone Disease in Multiple Myeloma

Simple Summary

Multiple myeloma bone disease (MMBD) is one of the most important complications of multiple myeloma with a great impact on quality of life. Recent advances in the field of imaging techniques provided clinicians with a variety of imaging modalities with high sensitivity for the diagnosis of MMBD. However, no circulating biomarkers are available to support the diagnosis of MMBD in cases where the results are inconclusive. The aim of our study was to investigate the clinical utility of 19 miRNAs implicated in osteoporosis in MMBD. Our results suggest that the levels of circulating let-7b-5p, miR-143-3p, miR-17-5p, miR-335-5p, and miR-214-3p (standalone or combined in multi-miRNA models) can effectively predict the presence of MMBD in newly diagnosed MM patients.

Abstract

Background: Multiple myeloma bone disease (MMBD) constitutes a common and severe complication of multiple myeloma (MM), impacting the quality of life and survival. We evaluated the clinical value of a panel of 19 miRNAs associated with osteoporosis in MMBD. Methods: miRNAs were isolated from the plasma of 62 newly diagnosed MM patients with or without MMBD. First-strand cDNA was synthesized, and relative quantification was performed using qPCR. Lastly, we carried out extensive biostatistical analysis. Results: Circulating levels of let-7b-5p, miR-143-3p, miR-17-5p, miR-214-3p, and miR-335-5p were significantly higher in the blood plasma of MM patients with MMBD compared to those without. Receiver operating characteristic curve and logistic regression analyses showed that these miRNAs could accurately predict MMBD. Furthermore, a standalone multi-miRNA–based logistic regression model exhibited the best predictive potential regarding MMBD. Two of those miRNAs also have a prognostic role in MM since survival analysis indicated that lower circulating levels of both let-7b-5p and miR-335-5p were associated with significantly worse progression-free survival, independently of the established prognostic factors. Conclusions: Our study proposes a miRNA signature to facilitate MMBD diagnosis, especially in ambiguous cases. Moreover, we provide evidence of the prognostic role of let-7b-5p and miR-335-5p as non-invasive prognostic biomarkers in MM.

miR‑139‑5p affects cell proliferation, migration and adipogenesis by targeting insulin‑like growth factor 1 receptor in hemangioma stem cells

Infant hemangioma is the most common benign tumor in infancy. The pathological development process of this tumor is separated into the proliferation period, the involution period and the composite period in which a few residual capillary-like vessels grow through the loose fibrofatty tissue. Previous studies have confirmed that insulin-like growth factor 1 (IGF-1) is able to facilitate the cell proliferation of hemangioma stem cells (HemSCs) and the differentiation of HemSCs into adipocytes. Additionally, studies have confirmed that microRNAs (miRs) may serve a crucial function in regulating the IGF-1 receptor (IGF-1R). miR-139-5p often functions as a tumor suppressor. The present study was designed to investigate the mechanism of miR-139-5p in HemSCs. Dual luciferase reporter results verified that IGF-1R is the target gene of miR-139-5p. miR-139-5p overexpression reduced IGF-1R expression, and miR-139-5p inhibition increased IGF-1R expression. Cell Counting Kit-8 and Transwell migration assays demonstrated that miR-139-5p overexpression may target IGF-1R to inhibit the proliferation in addition to the migration of HemSCs. Reverse transcription-quantitative PCR, oil red o staining and western blot analysis confirmed that miR-139-5p overexpression was able to reduce adipogen-esis in HemSCs via the IGF-1/IGF-1R pathway. In contrary, miR-139-5p inhibition substantially enhanced the proliferation, migration and adipogenesis of HemSCs. Overall, miR-139-5p is able to affect the IGF-1/IGF-1R pathway by regulating IGF-1R expression, which ultimately affects the proliferation, migration and adipogenesis of HemSCs.