Effects of miR-340 on hepatocellular carcinoma by targeting the DcR3 gene

The Role of Decoy Receptor DcR3 in Gastrointestinal Malignancy

Malignancies are among the leading causes of mortality worldwide. Early detection and treatment are the primary targets of clinical and translational research, and may be facilitated by the recognition of novel diagnostic and prognostic biomarkers. Decoy receptor 3 (DcR3) is a soluble receptor of the tumor necrosis factor receptor superfamily of proteins (TNFRSF), which associates with its respective TNF-like ligands, Fas-L, LIGHT, and TL1A. DcR3 has been recognised as a significant anti-apoptotic factor with prominent involvement in various inflammatory and neoplastic conditions. Increased intratumor expression of DcR3 and elevated soluble DcR3 protein content in the sera of patients has been reported for various malignancies. Recent published work has suggested that monitoring of local and systemic DcR3 may provide an attractive biomarker, mainly for defining subgroups of patients with aggressive tumor behaviour and poor prognosis. The aim of the present review is to summarize and critically present existing evidence regarding the potential clinical importance of monitoring DcR3 expression in patients with malignancies of the gastrointestinal tract, as well as liver and pancreatic cancer. We also present a detailed description of the pathophysiological basis that may underlie the involvement of DcR3 in gastrointestinal carcinogenesis. Based on these data, we comment on the potential applicability of DcR3 monitoring in the diagnosis and, most importantly, the prognostic stratification of patients.

Overexpression of miR-340 inhibits cell proliferation and induces apoptosis of human bladder cancer via targeting Glut-1

Background

Bladder cancer (BC) has high mortality due to distant metastasis. Previous works suggested that microRNA (miRNA)-340 is a critical regulator for the development and progression of various cancers. The specific biological function of miR-340 in BC is little known.

Methods

In the present study, RT-qPCR was performed to measure the expression of miR-340 in paired BC tissues and adjacent non-tumor tissues. Next, the target gene of miR-340 was identified using dual-luciferase reporter assay and its level was also tested in tissues. Moreover, cell proliferation and apoptosis were analyzed by CCK-8 and flow cytometry. Finally, the expression of PCNA, Bax was detected by RT-qPCR and western blotting, as well as PI3K/AKT signaling measured by western blotting.

Result

The results demonstrated that miR-340 expression was downregulated and its target Glut-1 level was upregulated in BC tissues. Functionally, overexpression of miR-340 suppressed the proliferation and induced apoptosis in BC cells, while Glut-1 reversed the suppression of proliferation or induction of apoptosis induced by miR-340. Additionally, miR-340 repressed PCNA, p-PI3K and p-AKT levels but enhanced Bax level, while Glut-1 rescued the effects.

Conclusion

In conclusion, miR-340 functions as a tumor suppressor of BC, which inhibited proliferation and induced apoptosis by targeting Glut-1 partly through regulating PCNA, Bax expression and PI3K/AKT pathway. This study suggested that miR-340 is a potential target for the treatment of BC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12894-021-00935-z.

miR-340 Promotes Retinoblastoma Cell Proliferation, Migration and Invasion Through Targeting WIF1

Background

MicroRNAs (miRNAs) function as important regulators of gene expression involved in tumor pathogenesis, including retinoblastoma. However, the expression profiles and potential roles in retinoblastoma are still largely unclear.

Material and Methods

Differentially expressed miRNAs (DEmiRs) and genes (DEGs) in retinoblastoma were extracted from Gene Expression Omnibus (GEO) repository. Expression levels of miR-340 and WIF1 were detected in retinoblastoma tissues and cell lines by qRT-PCR. Both gain-of-function and loss-of-function experiments were performed to explore the effects of miR-340 on cell proliferation, migration and invasion. Bioinformatics analysis and luciferase reporter assay were used to explore the interaction between miR-340 and WIF1.

Results

A total of 11 DEmiRs were identified in retinoblastoma tissue and blood samples. Among them, we validated that miR-340 was the most highly expressed miRNA and correlated with tumor size, ICRB stage and optic nerve invasion. miR-340 was observed to enhance the proliferation, migration and invasion capacity of retinoblastoma cells. We then identified 26 DEGs from 3 retinoblastoma GEO datasets and subsequently constructed a miRNA–mRNA regulatory network. Further analysis revealed that WIF1 was a direct target of miR-340. Moreover, overexpression of WIF1 could repress retinoblastoma progression induced by miR-340 in vitro and in vivo.

Conclusion

Collectively, miR-340 functioned as an oncomiRNA to promote retinoblastoma cell proliferation, migration and invasion via regulating WIF1. Our data also provided multiple miRNAs and genes that may contribute to a better understanding of retinoblastoma pathogenesis.

miR-340: A multifunctional role in human malignant diseases

MicroRNAs (miRNAs) are a class of short non-coding RNAs of approximately 22 nucleotides in length, which function by binding to the 3' UTR sequences of their target mRNAs. It has been reported that dysregulated miRNAs play pivotal roles in numerous diseases, including cancers, such as gastric, breast, colorectal, ovarian, and other cancers. Recent research efforts have been devoted to translating these basic discoveries into clinical applications that could improve the therapeutic outcome in patients with cancer. Early studies have shown that miR-340 may act either as an oncogene or a tumor suppressor by targeting genes related to proliferation, apoptosis, and metastasis, as well as those associated with diagnosis, treatment, chemoresistance, and prognosis. miR-340 has been shown to have a role in other diseases, such as autoimmune diseases, acute stroke, and alcoholic steatohepatitis. Nevertheless, the roles of miR-340 in human malignancies are still unclear, and the associated mechanisms are complex, involving a variety of signaling pathways, such as Wnt/β-catenin and the JAK-STAT pathways. Herein, we review the crucial roles of miR-340 in human cancers through the analysis of the latest research studies, with the aim of clarifying miR-340 function in malignant disease diagnosis, treatment, and prognosis, and to propose further investigations.

[Role of miRNA-340 in modulating gastric cancer cell proliferation and bioinformatic analysis]

OBJECTIVE

To investigate the mechanism of miRNA-340 for regulating the proliferation of gastric cancer (GC) cells and predict its interacting circular RNAs (circRNAs), its downstream target genes and the involved signaling pathways.

METHODS

The differentially expressed miRNAs in GC cell lines were analyzed and screened using miRNA microarrays. The expression level of miRNA-340 in 21 pairs of GC tissues and adjacent normal tissues was detected using real-time PCR. MTT and EdU assays were performed to examine the effect of miRNA-340 on the proliferation ability of HFE145 and BGC-823 cells. We also tested the effect of miRNA-340 inhibition on subcutaneous tumorigenesis of GC cells in a nude mouse model. The downstream target genes of miRNA-340 and the probable signal pathways were predicted online using Targetscan and DAVID database, respectively. The interacting circRNAs of miRNA-340 were analyzed using starBase platform.

RESULTS

Among the differentially expressed miRNAs, miRNA-340 was significantly down-regulated in GC cell lines. Real-time PCR results showed that the expression of miRNA-340 was significantly lower in GC tissues than in the adjacent tissues (P < 0.05). MTT and EdU cell proliferation assays showed that miRNA-340 overexpression inhibited the proliferation of GC cells in vitro. In the nude mouse models, the proliferation of GC cells transfected with miRNA-340 inhibitor was obviously enhanced. Bioinformatics analysis suggested that miRNA-340 had 21 target genes with 3 or more conserved sites, and these genes were involved in tumorigenesis and invasion. The top 10 circRNAs were selected as the most powerful sponge circRNAs interacting with miRNA-340.

CONCLUSIONS

miRNA-340 may play the role of a tumor suppressor in tumorigenesis and progression. Overexpression of miRNA-340 suppress the proliferation of GC cells, suggesting its involvement in the development of GC along with multiple circRNAs.

Effects of miR‑340 overexpression and knockdown on the proliferation and metastasis of NSCLC cell lines

The present study aimed to investigate the potential biological functions of microRNA‑340 (miR‑340) in non‑small cell lung cancer (NSCLC) beyond its role as a critical regulator of tumorigenesis and tumor progression. The expression levels of miR‑340 and RAB27B were analyzed by reverse transcription‑quantitative polymerase chain reaction. Subsequently, the protein expression levels of RAB27A, RAB27B, RAB9A, RAB11A and BRAB21 were determined by western blot analysis. The expression levels of the aforementioned proteins in NSCLC tissues were analyzed by immunohistochemistry. RAB27B, as a potential target of miR‑340 was investigated via a dual‑luciferase reporter assay. The proliferative ability of PC9, A549 and BEAS‑2B cells was detected with a Cell Counting kit‑8 assay, while the migration and invasion of the NSCLC cells were analyzed using a Transwell assay. The results revealed that the expression levels of miR‑340 in the NSCLC cells were significantly decreased compared with those in normal cells (BEAS‑2B cells). RAB27B was proposed as a potential target gene of miR‑340, and its expression was notably increased in the NSCLC cells. miR‑340 overexpression inhibited the migration and invasion of the NSCLC cells by targeting RAB27B, while the knockdown of miR‑340 exerted opposite effects. On the whole, these findings indicate that the miR‑340/RAB27B axis may be actively involved in the occurrence of NSCLC. Thus, miR‑340 and RAB27B may be novel therapeutic targets for the treatment of NSCLC.

Therapeutic potential of microRNAs in osteoporosis function by regulating the biology of cells related to bone homeostasis

MicroRNAs (miRNAs) are novel regulatory factors that play important roles in numerous cellular processes through the posttranscriptional regulation of gene expression. Recently, deregulation of the miRNA-mediated mechanism has emerged as an important pathological factor in osteoporosis. However, a detailed molecular mechanism between miRNAs and osteoporosis is still not available. In this review, the roles of miRNAs in the regulation of cells related to bone homeostasis as well as miRNAs that deregulate in human or animal are discussed. Moreover, the miRNAs that act as clusters in the biology of cells in the bone microenvironment and the difference of some important miRNAs for bone homeostasis between bone and other organs are mentioned. Overall, miRNAs that contribute to the pathogenesis of osteoporosis and their therapeutic potential are considered.

MicroRNA-340 inhibits the growth and invasion of angiosarcoma cells by targeting SIRT7

MicroRNAs (miRNAs) are emerging as critical regulators for the development and progression of various cancers, including angiosarcoma. Accumulating evidence suggests that miRNA-340 (miR-340) is an important cancer-associated miRNA. However, little is known about the role of miR-340 in angiosarcoma. In this study, we aimed to investigate the potential biological functions of miR-340 and its potential target gene in angiosarcoma. Our results showed that miR-340 expression was significantly decreased in angiosarcoma compared with normal controls. The overexpression of miR-340 inhibited the growth and invasion of angiosarcoma cells, while the inhibition of miR-340 showed the opposite effect. Bioinformatics analysis predicted that Sirtuin 7 (SIRT7) was a potential target gene of miR-340. The binding relationship between miR-340 and the SIRT7 3'-untranslated region was verified by dual-luciferase reporter assay. Moreover, our results showed that miR-340 negatively regulated SIRT7 expression in angiosarcoma cells and an inverse correlation between miR-340 and SIRT7 expression was shown in clinical angiosarcoma tissues. We found that silencing SIRT7 significantly inhibited the proliferation and invasion of angiosarcoma cells. Notably, the overexpression of SIRT7 promoted the proliferation and invasion of angiosarcoma cells and also partially reversed the antitumor effect of miR-340 on angiosarcoma cell proliferation and invasion. Taken together, our results demonstrate that miR-340 inhibits the growth and invasion of angiosarcoma cells by targeting SIRT7. Our study provides evidence that the miR-340/SIRT7 axis may play an important role in the molecular pathogenesis of angiosarcoma and suggests that miR-340 and SIRT7 may be used as potential and novel therapeutic targets for the treatment of angiosarcoma.

MiR-340/iASPP axis affects UVB-mediated retinal pigment epithelium (RPE) cell damage

Long-term exposure to ultraviolet B (UVB) light increases the risk of UVB damage due to increased UVB absorption by the retina and may further lead to age-related eye diseases. The retinal pigment epithelium (RPE) cell is a main target of UVB reaching the retina; its degeneration is an essential event in UVB-mediated age-related macular degeneration (AMD). Herein, we first evaluated the expression and effect of iASPP, an inhibitory regulator of apoptosis, in UVB-induced RPE cell damage. Through the mechanism of RNA interference at the post-transcriptional level, miRNA affects a variety of cellular processes, including UVB-mediated cell damage. We next screened for upstream candidate miRNAs that may regulate iASPP expression. Among 8 candidate miRNAs, UVB significantly increased miR-340 levels. We also confirmed the direct binding of miR-340 to the 3'UTR of iASPP, and assessed the combined effect of miR-340 and iASPP on UVB-induced RPE cell damage. Taken together, we demonstrated the possible mechanisms involved in UVB-induced retinal damage. In RPE cells, UVB irradiation inhibits iASPP expression through inducing miR-340 expression, thereby promoting RPE cell apoptosis and suppressing cell viability via affecting p53, p21 and caspase-3 protein expression. Targeting miR-340 to rescue iASPP expression in RPE cells may help treat UVB-mediated retinal damage.