LncRNA TMPO-AS1 serves as a ceRNA to promote osteosarcoma tumorigenesis by regulating miR-199a-5p/WNT7B axis

Osteosarcoma (OS) is a common kind of aggressive tumor in bone which was mostly identified in children and adolescents with extremely high risk of death. Accumulating research works have displayed that long noncoding RNAs (lncRNAs) exert an essential role in the development of multiple cancers. It has been reported that TMPO-AS1 is an oncogene in cancers; nonetheless, its molecular mechanism in OS is totally unclear. Our present study elucidated that a remarkable overexpression of TMPO-AS1 was found in OS tissues and cells. Moreover, TMPO-AS1 depletion restrained Wnt/β-catenin pathway and cell proliferation as well as facilitated cell apoptosis. Further molecular mechanism investigations showed that TMPO-AS1 can sponge to miR-199a-5p. Moreover, miR-199a-5p was at a low level at OS cells. Importantly, miR-199a-5p's overexpression was associated with the OS cells' decreased proliferation and increased apoptosis. In addition, WNT7B was confirmed as a downstream gene of miR-199a-5p. Also the WNT7B expression was reversely modulated by miR-199a-5p and positively modulated by TMPO-AS1. Rescue experiments suggested that downregulated WNT7B rescued miR-199a-5p inhibitor-mediated repression on OS progression, but the treatment of LiCl counteracted the effect of WNT7B downregulation. In a word, TMPO-AS1 serves as a competing endogenous RNA to boost osteosarcoma tumorigenesis by regulating miR-199a-5p/WNT7B axis, which provided an underlying therapeutic target for patients with OS.     

Sevoflurane protects cardiomyocytes against hypoxia/reperfusion injury via LINC01133/miR-30a-5p axis

Previous studies failed to elucidate the detailed mechanisms of anesthetic preconditioning as a protective approach against ischemic/reperfusion (I/R) injury in cells. The present study mainly centered on discovering the mechanisms of Sevoflurane (Sev) in preventing cardiomyocytes against I/R injury. Human cardiomyocyte AC16 cell line was used to simulate I/R injury based on a hypoxia/reperfusion (H/R) model. After Sev treatment, cell viability and apoptosis were detected by MTT assay and flow cytometry, respectively. Lactate dehydrogenase (LDH) content was measured using an LDH Detection Kit. Relative mRNA and protein expressions of LINC01133, miR-30a-5p and apoptosis-related proteins were detected using quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot as needed. Target gene of miR-30a-5p and their potential binding sites were predicted using Starbase and confirmed by dual-luciferase reporter assay. Cell behaviors were assessed again after miR-30a-5p and LINC01133 transfection. Sev could improve cell viability, reduce LDH leakage, and down-regulate the expressions of apoptosis-related proteins (Bax, cleaved caspase-3 and cleaved caspase-9) and LINC01133 as well as up-regulate miR-30a-5p and Bcl-2 expressions in H/R cells. MiR-30a-5p was the target of LINC01133, and up-regulating miR-30a-5p enhanced the effects of Sev in H/R cells, with a suppression on H/R-induced activation of the p53 signaling pathway. However, up-regulating LINC01133 reversed the enhancing effects of miR-30a-5p on Sev pretreatment in H/R cells. Sev could protect cardiomyocytes against H/R injury through the miR-30a-5p/LINC01133 axis, which may provide a possible therapeutic method for curing cardiovascular I/R injury.     

Circ-ERBB2 knockdown sensitized colorectal cancer cells to 5-FU via miR-181a-5p/PTEN/Akt pathway

Colorectal cancer (CRC) is the fourth most deadly cancer worldwide, drug resistance impedes treatment of CRC. It is still urgent to find new molecular targets to improve the sensitivity of chemotherapeutic drugs. In this study, circ-ERBB2 was upregulated in CRC cells. Upregulation of circ-ERBB2 promoted CRC cells proliferation and clone formation, but inhibited apoptosis. We identified miR-181a-5p as circ-ERBB2's target. The effect of miR-181a-5p on CRC cells was contrary to circ-ERBB2, miR-181a-5p downregulation abolished the function of circ-ERBB2 silencing in CRC cells. In addition, phosphatase and tensin homolog (PTEN) was verified as miR-181a-5p's downstream target, circ-ERBB2 activates the Akt pathway and inhibits cell apoptosis through modulating miR-181a-5p/PTEN. Circ-ERBB2 silencing significantly reduced CRC cell resistance to 5-FU. miR-181a-5p downregulation abolished the role of circ-ERBB2 knockdown in CRC cell resistance to 5-FU. In conclusion, upregulation of circ-ERBB2 promoted the malignancy of CRC and reduced CRC cell resistance to 5-FU. Besides, additional mechanism study provided a novel regulatory pathways that circ-ERBB2 knockdown promoted CRC cell sensitivity to 5-FU by regulating miR-181a-5p/PTEN/Akt pathway. This research indicated that circ-ERBB2 may be a valuable biomarker for the diagnosis and treatment of CRC.     

miR-15a-5p和miR-16-5p在骨肉瘤组织中的表达分析

目的:使用microRNAs基因芯片及实时定量PCR法测定骨肉瘤组织中miR-15a-5p和miR-16-5p的相对表达含量,并与瘤旁组织对比,分析骨肉瘤细胞内miR-15a-5p和miR-16-5p的表达变化。方法:选取34例骨肉瘤组织蜡块样本,使用microRNAs基因芯片观察miR-15a-5p和miR-16-5p在骨肉瘤和瘤旁组织内的表达差异;实时定量PCR法测定骨肉瘤组织和瘤旁组织中miR-15a-5p和miR-16-5p的相对表达含量,并将两种结果对比分析。结果:microRNAs基因芯片结果显示,在骨肉瘤组织中,miR-15a-5p在肿瘤中的表达较瘤旁组织低1.79倍,miR-16-5p较瘤旁组织低1.62倍。实时定量PCR实验结果表明,miR-15a-5p和miR-16-5p表达较瘤旁组织降低,差异有统计学意义(P0.05)。经过统计学计算,miR-15a-5p在肿瘤中的表达较瘤旁组织低3.14倍,miR-16-5p较瘤旁组织低5.65倍。结论:在骨肉瘤中,miR-15a-5p和miR-16-5p表达含量降低,提示这两种microRNAs在骨肉瘤中可能做为抑癌因子存在。     

LncRNA H19-elevated LIN28B promotes lung cancer progression through sequestering miR-196b

LncRNA H19 is involved in the development of multiple cancers. Here, we firstly provide new evidence that H19 can induce LIN28B, a conserved RNA binding protein, to accelerate lung cancer growth through sponging miR-196b. Abundance in LIN28B was observed in clinical lung cancer samples. A positive link was observed between H19 and LIN28B in clinical lung cancer samples. In lung cancer cells, H19 was capable of increasing LIN28B expression. Mechanistically, miR-196b directly targeted LIN28B to inhibit LIN28B expression. H19 was capable of promoting LIN28B expression through sequestering miR-196b. Functionally, H19-increased LIN28B conferred the cell proliferation of lung cancer. Our finding indicates that H19 depresses miR-196b to elevate LIN28B, resulting in accelerating cell proliferation in lung cancer.     

miR-103a-2-5p/miR-30c-1-3p inhibits the progression of prostate cancer resistance to androgen ablation therapy via targeting androgen receptor variant 7

Androgens and androgen receptors are vital factors involved in prostate cancer progression, and androgen ablation therapies are commonly used to treat advanced prostate cancer. However, the acquisition of androgen ablation therapy resistance remains a challenge. Recently, androgen receptor splicing variants lacking the ligand-binding domain have been reported to play a critical role in the acquisition of androgen ablation therapy resistance. In the present study, we revealed that the messenger RNA expression and the protein levels of an androgen receptor variant 7 (AR-V7) were higher in prostate cancer tissue samples and in the AR-positive prostate cancer cell line, VCaP. In contrast, microRNA (miR)-30c-1-3p/miR-103a-2-5p expression was significantly downregulated in tumor tissues and cells. miR-30c-1-3p/miR-103a-2-5p overexpression could inhibit AR-V7 expression, suppress VCaP cell growth, and inhibit AR-V7 downstream factor expression by directly targeting the 3′-untranslated region of AR-V7. Under enzalutamide (Enza) treatment, the effects of AR-V7 overexpression were the opposite of those of miR-103a-2-5p/miR-30c-1-3p overexpression; more importantly, the effects of miR-103a-2-5p/miR-30c-1-3p overexpression could be significantly reversed by AR-V7 overexpression under Enza. In summary, we demonstrated a novel mechanism of the miR-30c-1-3p/miR-103a-2-5p/AR-V7 axis modulating the cell proliferation of AR-positive prostate cancer cells via AR downstream targets. The clinical application of miR-30c-1-3p/miR-103a-2-5p needs further in vivo validation.     

p53/miR-30a-5p/ SOX4 feedback loop mediates cellular proliferation,apoptosis, and migration of non-small-cell lung cancer

Many microRNAs (miRNAs) play vital roles in the tumorigenesis and development of cancers. In this study, we aimed to identify the differentially expressed miRNAs and their specific mechanisms in non-small-cell lung cancer (NSCLC). Based on data from the GSE56036 database, miR-30a-5p expression was identified to be downregulated in NSCLC. Further investigations showed that overexpression of miR-30a-5p inhibited cell proliferation, migration, and promoted apoptosis in NSCLC. Increase of miR-30a-5p level could induce the increase of Bax protein level and decrease of Bcl-2 protein level. In addition, chromatin immunoprecipitation assays showed that miR-30a-5p expression was induced by binding of p53 to the promoter of MIR30A. Bioinformatics prediction indicated that miR-30a-5p targets SOX4, and western blot analysis indicated that overexpression of the miRNA decreases the SOX4 protein expression level, which in turn regulated the level of p53. Thus, this study provides evidence for the existence of a p53/miR-30a-5p/SOX4 feedback loop, which likely plays a key role in the regulation of proliferation, apoptosis, and migration in NSCLC, highlighting a new therapeutic target.     

Long noncoding RNA FOXD3-AS1 promotes colon adenocarcinoma progression and functions as a competing endogenous RNA to regulate SIRT1 by sponging miR-135a-5p

More and more documents have proved that the abnormal expression of long noncoding RNAs (lncRNAs) are correlated with the initiation and progression of colorectal cancer (CRC). lncRNA FOXD3-AS1 has been reported in glioma for its oncogenic property. According to the survival analysis of The Cancer Genome Atlas database, FOXD3-AS1 upregulation implied lower survival rate of patients with CRC. Quantitative real-time polymerase chain reaction showed the overexpression of FOXD3-AS1 in both CRC tissues and cells. The Kaplan–Meier method demonstrated the prognostic value of FOXD3-AS1 for patients with CRC. To explore the effect of FOXD3-AS1 on CRC progression, loss-of-function experiments were carried out, whose results indicated that knockdown of FOXD3-AS1 suppressed cell proliferation, migration, and invasion, inhibited cell cycle and promoted cell apoptosis in vitro. In vivo experiments affirmed that FOXD3-AS1 affected tumor growth. FOXD3-AS1 expression was enriched in the cytoplasm of CRC cells. Mechanism experiments revealed that FOXD3-AS1 served as a competing endogenous RNA to upregulate SIRT1 by sponging miR-135a-5p. In addition, SIRT1 silencing also restrained cell proliferation and motility. Rescue assays revealed the biological function of FOXD3-AS1/miR-135a-5p/SIRT1 axis in CRC progression. In conclusion, FOXD3-AS1 promotes CRC progression by regulating miR-135a-5p/SIRT1 axis, shedding lights on the way to CRC treatments.     

Downregulation of lysyl oxidase-like 4 LOXL4 by miR-135a-5p promotes lung cancer progression in vitro and in vivo

Aberrant microRNAs are widely identified in multiple cancers, including lung cancer. miR-135a-5p can function as a significant tumor regulator in diverse cancers via impacting multiple genes in oncogenic pathways. Nevertheless, the biological role of miR-135a-5p in lung cancer is poorly known. Here, we investigated its function in lung cancer. As exhibited, miR-135a-5p was elevated in lung cancer cells in contrast to BEAS-2B cells. Then, we inhibited miR-135a-5p expression by transfecting LV-anti-miR-135a-5p into lung cancer cells. As displayed, miR-135a-5p was obviously reduced in A549 and H1299 cells. Knockdown of miR-135a-5p repressed lung cancer cell growth and cell proliferation. Meanwhile, cell colony formation capacity was depressed, cell apoptosis was enhanced and cell cycle progression was blocked in G1 phase by inhibition of miR-135a-5p in vitro. Additionally, the migration and invasion of A549 and H1299 cells was strongly depressed by LV-anti-miR-135a-5p. For another, by using informatics analysis, lysyl oxidase-like 4 (LOXL4) was speculated as the downstream target of miR-135a-5p. We validated their direct correlation and moreover, overexpression of miR-135a-5p restrained LOXL4 levels in lung cancer cells. Subsequently, we proved that miR-135a-5p promoted lung cancer development via targeting LOXL4 by carrying out the in vivo assays. Taken these together, our study revealed miR-135a-5p might be indicated as a perspective for lung cancer via targeting LOXL4.     

Long noncoding RNA PRKCQ-AS1 promotes CRC cell proliferation and migration via modulating miR-1287-5p/YBX1 axis

Colorectal cancer (CRC) brings more than 600 000 deaths every year around the globe, making itself the third most frequently occurred carcinoma. The great progress human achieved in diagnosis and treatment of various cancers has failed to reverse this trend. Fortunately, growing evidence has implied the relationship between lncRNAs and cancer progression. Long noncoding RNA (lncRNA) PRKCQ-AS1 was heightened in CRC cells and tissues and related with dismal prognosis of CRC patients. Knockdown of PRKCQ-AS1 would induce a decrease in proliferative and migrating ability of CRC cells. Also, PRKCQ-AS1 enriched in cytoplasm of CRC cells and negatively regulated miR-1287-5p level. More important, PRKCQ-AS1 could bind to argonaute 2 and function in the RNA-induced silencing complex with miR-1287-5p. Therefore, PRKCQ-AS1 was a competing endogenous RNA for miR-1287-5p. Subsequently, it was validated that miR-1287-5p could suppress the proliferative and migratory functions in CRC. Furthermore, PRKCQ-AS1 could upregulate the mRNA and protein level of YBX1 targeted by miR-1287-5p. And YBX1 expression was elevated in CRC cells and tissues. Rescue assays in vitro and in vivo showed that overexpression of YBX1 could partly offset the effect of CRC progression induced by knocking down PRKCQ-AS1, demonstrating PRKCQ-AS1 mediating CRC progression via miR-1287-5p/YBX1 pathway.     

miR-548c-5p inhibits colorectal cancer cell proliferation by targeting PGK1

Accumulating studies have implicated that microRNAs (miRNAs) are involved in the pathogenesis of colorectal cancer (CRC). However, the role of miR-548c-5p, a novel identified miRNA in malignancies, in colorectal carcinogenesis remains largely unknown. The present study is aimed to investigate the effect and molecular mechanism of miR-548c-5p in CRC by a sequence of cellular experiments. miR-548c-5p was significantly downregulated, whereas phosphoglycerate kinase 1 (PGK1), a key enzyme for glycolysis, was obviously upregulated in peripheral blood mononuclear cells and cancer tissues from patients with CRC. Besides, miR-548c-5p and PGK1 were negatively associated with each other. The luciferase reporter assay revealed that PGK1 was a targeted gene of miR-548c-5p. Moreover, the proliferation and generation of inflammatory cytokines (TNF-α and IL-6) were significantly inhibited in miR-548c-5p-overexpressed SW480 CRC cells stimulated by lipopolysaccharide (LPS). Accordingly, miR-548c-5p may serve as a cancer suppressor in CRC by targeting PGK1.     

The lncRNA SNHG15/miR-18a-5p axis promotes cell proliferation in ovarian cancer through activating Akt/mTOR signaling pathway

Here, we report the expression pattern, function and regulatory mechanism of SNHG15 together with miR-18a-5p micro RNA in ovarian cancer (OC) for the first time. We recruited 20 patients and took normal ovarian tissues and ovarian tumor tissues from them. We used cell culture, transfection, in vivo tumor xenograft assay, and multiple types of detection assays to investigate the expression and regulation of long noncoding RNA (lncRNA) SNHG15/miR-18a-5p in ovarian tissues and cells. Results: We found that the messenger RNA expression level of SNHG15 was significantly higher and miR-18 was decreased in ovarian cancer tissues and in OC cells. Functional experiments showed that SNHG15 overexpression potentiated the migration and invasion of OC cells, while SNHG15 inhibition reduced the tumor proliferation, which was restored via overexpression of miR-18a. SNHG15 was found to directly target and suppress the expression of miR-18a. Our results illustrate the possible molecular mechanism of lncRNA SNHG15/miR-18a-5p functions in cell proliferation in OC. SNHG15/miR-18a promoted the progression of OC cells via the protein kinase B/mammalian target of rapamycin signaling pathway.     

Long non-coding RNA FEZF1-AS1 induced progression of ovarian cancer via regulating miR-130a-5p/SOX4 axis

Emerging studies have revealed the critical role of long non-coding RNAs (lncRNAs) in epithelial ovarian cancer (EOC) development and progression. Till now, the roles and potential mechanisms regarding FEZF1 antisense RNA 1 (FEZF1-AS1) within ovarian cancer (OC) remain unclear. The objective of this study was to uncover the biological function and the underlying mechanism of LncRNA FEZF1-AS1 in OC progression. FEZF1-AS1 expression levels were studied in cell lines and tissues of human ovarian cancer. In vitro studies were performed to evaluate the impact of FEZF1-AS1 knock-down on the proliferation, invasion, migration and apoptosis of OC cells. Interactions of FEZF1-AS1 and its target genes were identified by luciferase reporter assays. Our data showed overexpression of FEZF1-AS1 in OC cell lines and tissues. Cell migration, proliferation, invasion, wound healing and colony formation were suppressed by silencing of FEZF1-AS1. In contrast, cell apoptosis was promoted by FEZF1-AS1 knock-down in vitro. Furthermore, online bioinformatics analysis and tools suggested that FEZF1-AS1 directly bound to miR-130a-5p and suppressed its expression. Moreover, the inhibitory effects of miR-130a-5p on the OC cell growth were reversed by FEZF1-AS1 overexpression, which was associated with the increase in SOX4 expression. In conclusion, our results revealed that FEZF1-AS1 promoted the metastasis and proliferation of OC cells by targeting miR-130a-5p and its downstream SOX4 expression.