LINC02086 inhibits ferroptosis and promotes malignant phenotypes of pancreatic cancer via miR-342-3p/CA9 axis.

Long noncoding RNAs (lncRNAs) play important roles in modulating the tumorigenesis and progression of malignant tumors. LINC02086 is a newly identified oncogene associated with tumorigenesis, but its role in pancreatic cancer (PC) has not been fully elucidated. In this study we examined the expression levels of LINC02086, miR-342-3p, and CA9 in PC. The relationship of ferroptosis with these factors was analyzed by detecting the expression levels of Fe2+, reactive oxygen species (ROS), and ferroptosis marker proteins. The expression of these genes was altered to observe their effects on cell proliferation, migration, and invasion ability. Bioinformatics was used to predict target genes, and the binding relationship was verified luciferase reporter assay. Finally, the function of LINC02086 was evaluated in vivo. The findings suggest that LINC02086 is highly expressed in PC tissues and cell lines and is correlated with a poor prognosis. In vitro experiments demonstrated that LINC02086 knockdown promoted ferroptosis in PC cells to suppress their malignant phenotype. LINC02086 acts as a competitive endogenous RNA that adsorbed miR-342-3p. miR-342-3p hinders the malignant progression of PC by promoting ferroptosis. In addition, miR-342-3p targets CA9 and affects its function. Further mechanistic studies revealed that LINC02086 inhibits ferroptosis and promotes PC progression by acting as a sponge for miR-342-3p to upregulate CA9 expression. In vivo experiments further confirmed this mechanism. Taken together, LINC02086 upregulates CA9 expression by competitively binding with miR-342-3p, thereby inhibiting ferroptosis in PC cells and promoting their malignant phenotype. The results of our study provide new insights into how LINC02086 contributes to the progression of PC.

LINC00624 affects hepatocellular carcinoma proliferation and apoptosis through the miR-342-3p/DNAJC5 axis.

LINC00624 is a long noncoding RNA (lncRNA) which was seldom investigated before. The goal of our study is to clarify the expression and underlying network of LINC00624 in hepatocellular carcinoma (HCC). Here, both HCC and normal living cell lines were employed. Real-time quantitative PCR and western blot were used to determine the pattern of genes and proteins. Colony formation, flow cytometry and western blot tests were used to determine cell proliferation and apoptosis, respectively. Dual luciferase was used to verify molecule-molecule interactions. LINC00624 expression was increased in HCC cell lines and miR-342-3p was decreased. Elimination of LINC00624 increased proliferation while decreasing cell apoptosis. LINC00624 acted as a molecular sponge for miR-342-3p, hence facilitating DNAJC5 expression. Functional tests demonstrated that miR-342-3p suppression could reverse the effect of LINC00624 silence and overexpression of DNAJC5 significantly mitigated the biological consequences of miR-342-3p. These finding demonstrated that LINC00624 aggravated HCC progression by modulating proliferation and apoptosis via targeting miR-342-3p/DNAJC5 axis. These data support that inhibition of LINC00624 may a potential treatment strategies of HCC.

[miR-342-3p Promotes the Proliferation, Migration, and Invasion of Clear Cell Renal Cell Carcinoma Cells by Targeted Inhibition of PPM1E]. / miR-342-3p通过靶向抑制PPM1E促进肾透明细胞癌细胞的增殖、迁移和侵袭.

Objective: To explore the effects of microRNA-342-3p/Mg2+Mn2+-dependent protein phosphatase 1E (miR-342-3p/PPM1E) on the proliferation, migration, and invasion of clear cell renal cell carcinoma (ccRCC) cells. Methods: The gene chips GSE12105, GSE23085, GSE66271, and GSE66270 were searched, and the relationship between miR-342-3p, PPM1E, and the clinical malignant phenotypes of ccRCC was analyzed. ACHN and 769-P cells were transfected with miR-342-3p inhibitor. The effects of miR-342-3p on cell proliferation, migration, and invasion were examined. ACHN cell line with stable and high expression of miR-342-3p was constructed, and the tumorigenicity of the cell line in BALB/c nude mice was observed. The targeted relationship between miR-342-3p and PPM1E was verified by dual-luciferase reporter gene assay. The cells were transfected with miR-342-3p mimic and pcDNA-PPM1E plasmids to observe whether PPM1E could reverse the effects of miR-342-3p overexpression on the proliferation, migration, and invasion of the cells. Results: The expression of miR-342-3p was upregulated in ccRCC, and there were significant differences among patients with tumors of different T stages and G stages and those with different prognoses (P<0.05). The overall survival in the miR-342-3p high-expression group was significantly shorter than that in the low-expression group (P<0.05). Compared with those in the miR-NC group, the miR-342-3p level was significantly downregulated in the inhibitor group, and the cell proliferation ability and the numbers of migrating and invading cells were also significantly decreased (P<0.05). Compared with the miR-NC group, miR-342-3p group had significantly increased volume and mass of tumor tissues and miR-342-3p level, but significantly decreased level of PPM1E mRNA (P<0.05). The expression of PPM1E was downregulated in ccRCC, and there were significant differences among patients with tumors of different M stages, N stages, and G stages, and different recurrence statuses (P<0.05). The miR-342-3p could inhibit the expression of PPM1E in a targeted way. Compared with the miR-NC group, the miR-342-3p group had significantly increased cell proliferation ability and increased numbers of migrating and invading cells (P<0.05). However, PPM1E could reverse the promotion effect of miR-342-3p mimic on ccRCC cells (P<0.05). Conclusion: The miR-342-3p can inhibit PPM1E expression in a targeted way, and thus promotes the proliferation, migration, and invasion of ccRCC cells.

Tenogenic differentiation of human tendon-derived stem cells induced by long non-coding RNA LINCMD1 via miR-342-3p/EGR1 axis.

BACKGROUND: Tendon-derived stem cells (TDSCs) are proposed as a potential cell-seed for the treatment of tendon injury due to their tenogenic differentiation potential. In this work, we defined the action of long non-coding RNA (lncRNA) muscle differentiation 1 (LINCMD1) in tenogenic differentiation of human TDSCs (hTDSCs). METHODS: Quantitative real-time PCR (qRT-PCR) was used to assess the levels of LINCMD1, microRNA (miR)-342-3p, and early growth response-1 (EGR1) mRNA. Cell proliferation was detected by the XTT colorimetric assay. Protein expression was quantified by western blot. hTDSCs were grown in an osteogenic medium to induce osteogenic differentiation, and the extent of osteogenic differentiation was assessed by Alizarin Red Staining (ARS). The activity of alkaline phosphatase (ALP) was measured by the ALP Activity Assay Kit. Dual-luciferase reporter and RNA immunoprecipitation (RIP) assays were used to evaluate the direct relationship between miR-342-3p and LINCMD1 or EGR1. RESULTS: Our results showed that enforced expression of LINCMD1 or suppression of miR-342-3p accelerated the proliferation and tenogenic differentiation and reduced osteogenic differentiation of hTDSCs. LINCMD1 regulated miR-342-3p expression by binding to miR-342-3p. EGR1 was identified as a direct and functional target of miR-342-3p, and knockdown of EGR1 reversed the effects of miR-342-3p suppression on cell proliferation and tenogenic and osteogenic differentiation. Furthermore, the miR-342-3p/EGR1 axis mediated the regulation of LINCMD1 on hTDSC proliferation and tenogenic and osteogenic differentiation. CONCLUSION: Our study suggests the induction of LINCMD1 in tenogenic differentiation of hTDSCs through miR-342-3p/EGR1 axis.

LncRNA TP73-AS1 promotes nasopharyngeal carcinoma progression through targeting miR-342-3p and M2 polarization via exosomes.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a deadly cancer, mainly presenting in southeast and east Asia. Long noncoding RNAs (lncRNAs) play essential roles in cancer progression. Exosomes are critical for intercellular communication. Thus, the aim of this study was to identify the functional lncRNAs in NPC and its relevant mechanisms. METHODS: Data from public databases were utilized to screen for functional lncRNAs in NPC. Functional and mechanical experiments were performed to determine the role of lncRNAs in NPC and its relative molecular mechanisms. Exosomes derived from NPC cells were isolated to determine their function in tumor-associated macrophages. RESULTS: LncRNA TP73-AS1 was increased in NPC cells and tissues and was associated with a poor prognosis. TP73-AS1 overexpression promoted proliferation, colony formation, and DNA synthesis of NPC cells while TP73-AS1 knockdown showed opposite roles. TP73-AS1 could directly bind with miR-342-3p. MiR-342-3p overexpression attenuated the effect of TP73-AS1 in NPC cells. Furthermore, TP73-AS1 was transferred by exosomes to promote M2 polarization of macrophages. Lastly, exosomal TP73-AS1 enhanced the motility and tube formation of macrophages. CONCLUSIONS: Together, this study suggests that TP73-AS1 promotes NPC progression through targeting miR-342-3p and exosome-based communication with macrophages and that TP73-AS1 might be an emerging biomarker for NPC.

MiR-342-3p inhibits LCSC oncogenicity and cell stemness through HDAC7/PTEN axis.

OBJECTIVE: This study aims to explore the effects of miR-342-3p on liver cancer stem cells (LCSC) and related mechanism. METHODS: LCSC were sorted using immunomagnetic beads and flow cytometry was used to determine CD133+ and CD133- sorted cells. The self-renewal ability and growth ability of LCSC were measured by tumor spheroid formation assay and soft agar colony formation assay. Protein and mRNA expressions of CD44, ALDH1, Bmi1, Sox2 and Oct4 were detected by western blot and quantitative PCR. The relationship between miR-342-3p and HDAC7 was analyzed by dual-luciferase assay. The acetylation level of H3 protein was measured by acetyl Lysine antibody. RESULTS: miR-342-3p overexpression in LCSC lead to lower tumor volume, reduced tumor spheroid formation and agar colony formation rates, as well as lower mRNA and protein expressions of CD44, ALDH1, Bmi1, Sox2, and Oct4. Dual-luciferase reporter assay confirmed HDAC7 as a target gene of miR-342-3p. Inhibition of HDAC7 or overexpression of PTEN suppressed the carcinogenicity and stemness of LCSC. PTEN expression was increased in sh-HDAC7 group and decreased in pcDNA3.1-HDAC7 group. HDAC7 promoted H3 deacetylation and inhibited PTEN expression. Overexpression of HDAC7 or silencing of PTEN could reverse the inhibitory effect of overexpression of miR-342-3p on LCSC carcinogenicity and cell stemness. CONCLUSION: MiR-342-3p inhibited LCSC oncogenicity and cell stemness by promoting PTEN and inhibiting HDAC7.

Downregulatory effect of miR-342-3p on epileptogenesis in the PTZ-kindling model.

BACKGROUND: Epileptogenesis is a process that results in neurons firing abnormally, causing seizures. Increasing evidence has shown that miRNAs expressed in the epileptic hippocampus are involved in epileptogenesis. We demonstrated the expression changes of miRNAs that may be effective in epileptogenesis in silico analysis in the kindling model created with Pentylenetetrazole (PTZ). Thus, we aimed to identify the target genes responsible for epileptogenesis. METHODS AND RESULTS: Fifteen male Wistar-albino rats (200-230 g) were randomly divided into two groups control (n = 6) and PTZ (n = 9). The control group received 0.5 ml saline, and the PTZ group (35 mg/kg i.p.) intraperitoneally (i.p.) (11 times, every other day) to induce tonic-clonic seizures. Seizures were observed and scored 30 min after PTZ injection. After the last dose of PTZ (75 mg/kg) administration, the hippocampus tissues of the rats were removed by anesthesia. Analysis of miRNAs was performed with the Affymetrix gene chip miRNA sequence (728 miRNA) and confirmed by the Real-Time Polymerase Chain Reaction (Real-Time PCR) method (29 miRNAs). We evaluated the expression change of the target gene of miRNA, whose expression change was detected using in silico analysis, by q-RT PCR. Eight miRNAs with changes in expression were detected. Of these miRNAs, miR-342-p was downregulated in the PTZ group and was statistically significant (p < 0.005). Ultimately, we determined that the target gene of miR-342-p is a metabotropic glutamate receptor 2 (GRM2) and that GRM2 expression is upregulated. CONCLUSIONS: Downregulation of miR-342-3p in the PTZ kindling model may result in the upregulation of GRM2.

MicroRNA-342-3p regulates yak oocyte meiotic maturation by targeting DNA methyltransferase 1.

MicroRNAs (miRNAs) play vital roles in the development of oocytes and ovarian follicles. We have previously shown differential expression of miR-342-3p during yak oocyte maturation. In this study, we investigated the role of miR-342-3p in meiotic maturation of yak oocytes and the underlying mechanism. The profile of ovarian DNA methyltransferase 1 (DNMT1) expression was investigated in yak by RT-qPCR and western blot analyses. The pattern of Dnmt1 expression in various meiotic stages (GV stage, MI stage and MII stage) of yak oocyte maturation was then measured by immunofluorescence staining. The interaction between Dnmt1 and miR-342-3p was verified by dual-luciferase reporter assay. Finally, miR-342-3p inhibitors were microinjected into yak cumulus-oocyte complex to evaluate the effects on oocyte maturation. MiR-342-3p expression was upregulated in oocytes during meiotic maturation, with significantly higher levels in the MII stage compared with the GV- and MI stages (p < .05), whereas the opposite pattern of Dnmt1 expression was detected. In the period to sexual maturity (3-year-old), DNMT1 showed an age-related pattern of ovarian expression at both the gene and protein levels. Immunohistochemistry analysis also indicated maturation-stage-related differences in DNMT1 expression in the ovarian follicles and corpus luteum, with expression predominantly detected in cumulus cells and oocytes. MiR-342-3p inhibitors effectively upregulated Dnmt1 expression and significantly inhibited oocyte meiotic maturation. Taken together, our results indicate that miR-342-3p plays a vital role in the meiotic maturation of yak oocytes by targeting the 3'-untranslated regions (UTR) of Dnmt1 and provide a new perspective on the mechanism of this process.

Exosomal LncRNA LINC00659 transferred from cancer-associated fibroblasts promotes colorectal cancer cell progression via miR-342-3p/ANXA2 axis.

BACKGROUND: Cancer-associated fibroblasts (CAFs) play a pivotal role in regulating tumor progression by transferring exosomes to adjacent cells. Our aim was to clarify the role of LINC00659 encapsulated in CAFs-derived exosomes (CAFs-exo) in colorectal cancer (CRC). METHODS: CAFs and normal fibroblasts (NFs) were isolated and cultured. CAFs-exo and NFs-derived exosomes (NFs-exo) were characterized by transmission electron microscope and Western blot. The mRNA level of LINC00659 in CAFs-exo and NFs-exo were measured. Then we analyzed cell proliferation by CCK-8 and clone formation assay, cell migration by cell scratch, and cell invasion by Transwell. Epithelial mesenchymal transformation (EMT) related markers E-cadherin, N-cadherin, Vimentin and Snail-1 expressions were assessed by Western blot. The binding of LINC00659 and miR-342-3p, miR-342-3p and ANXA2 were analyzed by dual-luciferase reporter gene assay. RESULTS: CAFs and NFs showed a spindle-like morphology. CAFs-exo promoted CRC cell proliferation, migration, invasion and EMT progression. The expression of LINC00659 in CAF-derived exosomes was significantly increased, and fibroblasts could transfer exosomal LINC00659 to CRC cells. We further revealed that transfection of miR-342-3p mimic or sh-ANXA2 could obviously reverse the promotion effect of exosomal LINC00659 on CRC progression. Functional studies reveal that LINC00659 is transferred from CAFs to the cancer cells via exosomes, where it promotes CRC cell proliferation, invasion, migration and EMT progression in vitro. Mechanistically, LINC00659 interacts directly with miR-342-3p to increase ANXA2 expression in CRC cells. CONCLUSION: Collected evidence supported that CAFs-derived exosomal LINC00659 promotes CRC cell proliferation, invasion and migration via miR-342-3p/ANXA2axis.

Effects of single bouts of different endurance exercises with different intensities on microRNA biomarkers with and without blood flow restriction: a three-arm, randomized crossover trial.

PURPOSE: Physical activity is associated with altered levels of circulating microRNAs (ci-miRNAs). Changes in miRNA expression have great potential to modulate biological pathways of skeletal muscle hypertrophy and metabolism. This study was designed to determine whether the profile of ci-miRNAs is altered after different approaches of endurance exercise. METHODS: Eighteen healthy volunteers (aged 24 ± 3 years) participated this three-arm, randomized-balanced crossover study. Each arm was a single bout of treadmill-based acute endurance exercise at (1) 100% of the individual anaerobic threshold (IANS), (2) at 80% of the IANS and (3) at 80% of the IANS with blood flow restriction (BFR). Load-associated outcomes (fatigue, feeling, heart rate, and exhaustion) as well as acute effects (circulating miRNA patterns and lactate) were determined. RESULTS: All training interventions increased the lactate concentration (LC) and heart rate (HR) (p < 0.001). The high-intensity intervention (HI) resulted in a higher LC than both lower intensity protocols (p < 0.001). The low-intensity blood flow restriction (LI-BFR) protocol led to a higher HR and higher LC than the low-intensity (LI) protocol without BFR (p = 0.037 and p = 0.003). The level of miR-142-5p and miR-197-3p were up-regulated in both interventions without BFR (p < 0.05). After LI exercise, the expression of miR-342-3p was up-regulated (p = 0.038). In LI-BFR, the level of miR-342-3p and miR-424-5p was confirmed to be up-regulated (p < 0.05). Three miRNAs and LC show a significant negative correlation (miR-99a-5p, p = 0.011, r = - 0.343/miR-199a-3p, p = 0.045, r = - 0.274/miR-125b-5p, p = 0.026, r = - 0.302). Two partial correlations (intervention partialized) showed a systematic impact of the type of exercise (LI-BFR vs. HI) (miR-99a-59: r = - 0.280/miR-199a-3p: r = - 0.293). CONCLUSION: MiRNA expression patterns differ according to type of activity. We concluded that not only the intensity of the exercise (LC) is decisive for the release of circulating miRNAs-as essential is the type of training and the oxygen supply.

Circular RNA circVAPA contributes to non-small-cell lung cancer progression via miR-342-3p-dependent regulation of ZEB2.

BACKGROUND: Accumulating evidence demonstrated that circular RNAs (circRNAs) play pivotal regulatory roles in the pathology of cancers. Disclosing the roles and molecular mechanisms of circRNAs in tumorigenesis and development is essential to identify novel diagnostic and therapeutic targets. In this study, we explored the role of circVAPA in non-small-cell lung cancer (NSCLC) progression and its associated mechanism. METHODS: The expression level of RNA was analyzed by real-time quantitative polymerase chain reaction (RT-qPCR). Cell proliferation was assessed by MTT assay and colony-forming assay. Cell apoptosis was analyzed by flow cytometry. Cell migration and invasion were assessed by transwell assays. Dual-luciferase reporter, RNA pull-down, and RNA immunoprecipitation (RIP) assays were used to test the intermolecular interactions. The role of circVAPA was assessed in vivo. And xenograft tumor tissues were analyzed by immunohistochemistry (IHC) staining. RESULTS: CircVAPA expression was upregulated in NSCLC tissues and cell lines, and a high level of circVAPA was associated with a poor prognosis of NSCLC patients. CircVAPA silencing suppressed the proliferation, migration, and invasion and induced the apoptosis of NSCLC cells. CircVAPA served as a molecular sponge for microRNA-342-3p (miR-342-3p). miR-342-3p interference largely reversed circVAPA knockdown-mediated anti-tumor effects in NSCLC cells. Zinc finger E-box-binding homeobox 2 (ZEB2) was a target of miR-342-3p, and miR-342-3p overexpression suppressed the malignant behaviors of NSCLC cells largely by downregulating ZEB2. CircVAPA silence repressed xenograft tumor growth in vivo, and IHC assay confirmed that circVAPA silence restrained the proliferation and metastasis but induced the apoptosis of NSCLC cells in vivo. CONCLUSION: CircVAPA contributes to the progression of NSCLC by binding to miR-342-3p to upregulate ZEB2. CircVAPA/miR-342-3p/ZEB2 axis might be a novel potential target for NSCLC treatment.

LncRNA SNHG7 promotes glioma cells viability, migration and invasion by regulating miR-342-3p/AKT2 axis.

PURPOSE: Glioma has been categorized as the most common primary malignant brain tumor. Long non-coding RNA SNHG7 (lncRNA SNHG7) has been recognized in various cancers as a possible oncogene. In this study, the effect of SNHG7 on glioma cells was investigated. MATERIALS AND METHODS: Thirty glioma tissues and adjacent normal tissues were collected. Pc-SNHG7, sh-SNHG7, miR-342-3p mimic and miR-342-3p inhibitor were transfected into the glioma cells. Cell Counting Kit-8, Transwell and scratch assay evaluated glioma cells viability, invasion and migration, respectively. TargetScan, Starbase and dual-luciferase reporter were used to predict and confirm the target genes and potential binding sites of SNHG7, miR-342-3p and AKT2. Relative miR-342-3p and AKT2 expressions were assessed by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot. Pearson's analysis was adopted for correlation analysis between SNHG7, miR-342-3p and AKT2. RESULTS: SNHG7 expressions in glioma tissues and cells were increased, upregulation of SNHG7 promotes cell viability, invasion and migration. SNHG7 was shown to bind with miR-342-3p, and upregulating SNHG7 reduced miR-342-3p expression. AKT2 was the target gene of miR-342-3p, and miR-342-3p expression was decreased while AKT2 expression was increased in glioma tissues. High expression of miR-342-3p inhibited cell viability, invasion and migration and reduced AKT2 expression, whereas low expression of miR-342-3p did the opposite effect. CONCLUSIONS: Upregulating SNHG7 might promote glioma cells viability, migration and invasion with the regulation of decreasing miR-342-3p level and increasing AKT2 level.

Long non-coding RNA SCARNA2 induces cutaneous squamous cell carcinoma progression via modulating miR-342-3p expression.

BACKGROUND: Long non-coding RNAs (lncRNAs) play important roles in the progression of tumors. However, the function and expression of SCARNA2 in cutaneous squamous cell carcinoma (cSCC) is still unreported. METHODS: A quantitative polymerase chain reaction was applied to study the expression of SCARNA2 and miR-342-3p. Cell counting kit-8, flow cytometry and transwell assays were performed to study cell growth, cycle and cell invasion. RESULTS: We found that SCARNA2 expression is up-regulated in cSCC cell lines and SCARNA2 expression is higher in cSCC tissues than in adjacent non-tumor specimens. Ectopic expression of SCARNA2 promoted cell growth, cell cycle and invasion in SCC13 cells. In addition, the data indicate that miR-342-3p expression is down-regulated in cSCC cell lines and miR-342-3p is down-regulated in cSCC tissues compared to adjacent non-tumor specimens. We showed that the SCARNA2 expression is negatively associated with miR-342-3p in cSCC. Moreover, we noted that SCARNA2 sponges miR-342-3p expression in cSCC cells. Overexpression of SCARNA2 suppressed the miR-342-3p expressed in SCC13 cells. We found that elevated expression of SCARNA2 promotes cell growth, cell cycle and invasion via regulating miR-342-3p expression in SCC13 cells. CONCLUSIONS: These data suggest that SCARNA2 acts in an oncogenic role and may be a potential target for cSCC.

Knockdown of lncRNA SNHG16 suppresses multiple myeloma cell proliferation by sponging miR-342-3p.

BACKGROUND: Aberrant expression of long non-coding RNAs (lncRNAs) is closely associated with development and prognosis of human cancers. LncRNA SNHG16 is reportedly involved in human cancer; however, its roles in multiple myeloma (MM) remain unclear. METHODS: In this study, we investigated the function and molecular mechanisms of SNHG16 in MM. MM cells were transfected with si-SNHG16 or si-NC. SNHG16 expression levels was measured by qRT-PCR. Cell proliferation was monitored using the MTS. Flow cytometry assay was performed to measure the cell cycle and apoptosis. Luciferase reporter assay were performed to confirm the sponged miRNAs of SNHG16. RESULTS: SNHG16 expression was up-regulated in MM tissues. SNHG16 knockdown suppressed cell proliferation, arrested cell cycle transition from G1 to S phase, and promoted the apoptosis of MM cells. Moreover, SNHG16 knockdown promoted cleaved-Caspase-3, cleaved-Caspase-9, Foxa3a, and Bax expression, while markedly inhibiting CCND1, Bcl-2, Cyclin D1, PI3K, and p-AKT expression in MM cells. miR-342-3p was a direct target of SNHG16. SNHG16 knockdown significantly increased miR-342-3p expression in MM cells. Overexpression miR-342-3p markedly suppressed cell proliferation, arrested cell cycle transition from G1 to S phase, and promoted apoptosis of MM cells. Overexpression of miR-342-3p markedly promoted cleaved-Caspase-3/-9, Foxa3a, and Bax expression, and inhibited CCND1, Bcl-2, Cyclin D1, PI3K, and p-AKT expression in MM cells. Additionally, repression of miR-342-3p could rescue the effect of SNHG16 knockdown on MM cell proliferation, cycle arrest, apoptosis, and related protein expression. CONCLUSION: Knockdown of lncRNA SNHG16 suppresses MM cell proliferation by sponging miR-342-3p, implicating SNHG16 as a novel therapeutic target for MM.

LINC01503/miR-342-3p facilitates malignancy in non-small-cell lung cancer cells via regulating LASP1.

BACKGROUND: Non-small cell lung cancer (NSCLC) is one of the major types of lung cancer, which is a prevalent human disease all over the world. LncRNA LINC01503 is a super-enhancer-driven long non-coding RNA that is dysregulated in several types of human cancer. However, its role in NSCLC remains unknown. METHODS: Thirty NSCLC patients were recruited between April 2012 and April 2016. Luciferase reporter assay, qRT-PCR, Cell Counting Kit-8 (CCK-8), Transwell migration assay, RNA pull-down assay, western blotting, 5-ethynyl-29-deoxyuridine (EdU) assays, and flow cytometry were utilized to characterize the roles and relationships among LINC01503, miR-342-3p, and LASP1 in NSCLC. The transplanted mouse model was built to examine their biological functions in vivo. RESULTS: We demonstrated that the expression of lncRNA LINC01503 and LIM and SH3 domain protein 1 (LASP1) were upregulated and miR-342-3p was downregulated in NSCLC samples and cell lines. Functional experiments revealed that inhibiting the expression of LINC01503 or over-expression of miR-342-3p inhibited NSCLC growth and metastasis both in vitro and in vivo. In addition, LINC01503 could bind to miR-342-3p and affect the expression of LASP1. CONCLUSION: These results provide a comprehensive analysis of the roles of LINC01503 as a competing endogenous RNA (ceRNA) in NSCLC progression.

Circular RNA CCDC66 facilitates abdominal aortic aneurysm through the overexpression of CCDC66.

Abdominal aortic aneurysm (AAA) is fatal meanwhile unpredictable asymptomatic cardiovascular disease. Available data suggests the potential participation of circular RNAs (circRNAs) in AAA pathogenesis. But direct evidence is limited. The present study is to functionally and mechanically characterize circRNA CCDC66 (circCCDC66) in AAA. Previous work indicated the differentially expressed circCCDC66 in AAA. At molecular level, circCCDC66, miR-342-3p and CCDC66 transcript were measured through real-time quantitative polymerase chain reaction assay. Functionally, we examined the cellular behaviours of circCCDC66-depleted or CCDC66-depleted vascular smooth muscle cells (VSMCs) including proliferation and apoptosis. It elucidated that depletion of circCCDC66 induced proliferation facilitation and apoptosis reduction. Mechanically, we addressed the interplay among circCCDC66, miR-342-3p and CCDC66 transcript using RNA immunoprecipitation, RNA pull-down and luciferase reporter experiments. Through mechanical validation, we discovered the positive regulation of circCCDC66 on its host gene CCDC66. Loss of CCDC66 mimicked the effects of circCCDC66 silencing on VSMC growth. Moreover, it uncovered that circCCDC66 regulated CCDC66-dependent VSMC growth through sponging miR-342-3p. Rescue experiments aimed to address the functional role of regulatory network formed by circCCDC66, miR-342-3p and CCDC66 in VSMC growth and apoptosis. Suppressing miR-342-3p or overexpressing CCDC66 could reverse VSMC growth caused by circCCDC66 deficiency. Our study further emphasized and first unveiled the function of circCCDC66 in VSMC proliferation. CircCCDC66 upregulated its host gene through its role of miR-342-3p sponge, and hinted a novel molecular mechanism in AAA. SIGNIFICANCE OF THE STUDY: It was firstly displayed in our study that depletion of circCCDC66 induced proliferation augmentation and apoptosis reduction of vascular smooth muscle cells (VSMCs). Meanwhile, circCCDC66/miR-342-3p/CCDC66 axis was proved can play the function of modulating the cell proliferation and apoptosis of VSMCs, which provided us a novel molecular mechanism in AAA.

LncRNA LINC00210 regulated radiosensitivity of osteosarcoma cells via miR-342-3p/GFRA1 axis.

BACKGROUND: Radiotherapy is an effective strategy for preventing cancer metastasis, including osteosarcoma. However, cancer radioresistance limits the efficiency of radiotherapy. Therefore, it is essential to investigate the mechanism of osteosarcoma radioresistance. METHODS: The osteosarcoma tissues and adjacent healthy tissues were collected from 53 osteosarcoma patients. The expression of LINC00210, miR-342-3p, and GFRA1 mRNA were determined using qRT-PCR. Cell viability, cell apoptosis, and cell surviving fraction were determined by MTT assay, flow cytometry, and colony formation assay, respectively. Western blot was performed to detect the protein levels. Luciferase assay was conducted to verify the relationship between LINC00210, miR-342-3p, and GFRA1. RESULTS: LINC00210 and GFRA1 were up-regulated, and miR-342-3p was down-regulated in osteosarcoma tissues and cells. The expression of LINC00210 in osteosarcoma was negatively related to miR-342-3p expression and positively associated with GFRA1. Besides, there was a negative correlation between LINC00210 and GFRA1 expression in osteosarcoma. Also, LINC00210 and GFRA1 were up-regulated, and miR-342-3p was down-regulated in osteosarcoma cells exposed to 4 Gy irradiation treatment. Furthermore, either LINC00210 knockdown or miR-342-3p overexpression enhanced the radiosensitivity of osteosarcoma cells. Moreover, LINC00210 increased GFRA1 expression via sponging miR-342-3p. Additionally, LINC00210 knockdown improved the radiosensitivity of osteosarcoma cells by regulating GFRA1 expression via sponging miR-342-3p. CONCLUSION: LINC00210 modulated the radiosensitivity of osteosarcoma cells via the miR-342-3p/GFRA1 axis, making LINC00210 a novel target for improving radiotherapy efficiency in osteosarcoma.

MiR-342-3p inhibition promotes cell proliferation and invasion by directly targeting ID4 in pre-eclampsia.

AIM: This study aimed to explore the miR-342-3p expression in pre-eclampsia (PE) placentas and confirm whether miR-342-3p exerts effects on proliferation and migration of HTR-8/SVneo trophoblastic cells. METHODS: The PE placentas (n = 8) were taken from gravidas complicated by PE and delivered after 34 weeks. The chorionic plates and the basal plates were separately taken from the placenta disc near the position of umbilical cord insertion. RT-qPCR was used to measure the expression of miR-342-3p in the chorionic plates and the basal plates. Cell invasion assay and MMT assay were used to assess the effects of miR-342-3p on proliferation and migration of HTR-8/SVneo trophoblastic cells. Luciferase reporter assay and Western blotting were used to analyze the target of miR-342-3p and investigate the detailed mechanisms. RESULTS: The expression of miR-342-3p was upregulated in both basal plates and chorionic plates in patients with PE compared with healthy pregnant individuals. MiR-342-3p inhibitor suppressed the cell viability and invasion, and induced apoptosis in trophoblast cells. Furthermore, inhibitor of DNA binding (ID)-4 (ID4) was a direct target of miR-342-3p, and knockdown of ID4 abrogated the regulation effect of miR-342-3p on cell viability, apoptosis and invasion. CONCLUSION: Inhibition of miR-342-3p expression may suppress the occurrence of PE by targeting ID4 in vitro.

The Role of miR-342 in Vascular Health. Study in Subclinical Cardiovascular Disease in Mononuclear Cells, Plasma, Inflammatory Cytokines and PANX2.

Cardiovascular disease (CVD) correlates with inflammation and a reduction in circulating endothelial progenitor cells (cEPCs). Recently, CVD was shown to be the main cause of mortality in individuals with type 1 diabetes (T1DM). In animals, miR-342 was shown to exert an anti-inflammatory effect in CVD. Hypothesis: miR-342-3p/-5p are downregulated in subclinical CVD (T1DM), whereas inflammatory cytokines are upregulated. We studied miR -342 -3p/5p in plasma/peripheral blood mononuclear cells (PBMCs) in 29 T1DM and 20 controls (HC). Vascular health was measured by fibronectin adhesion assay (FAA), cEPCs (CD45dimCD34+133+ cells) and by assessing inflammation and tissue inhibition of metalloproteases (TIMP-1). In T1DM IL-7, IL-8, TNFα and VEGF-C were increased in plasma. MiR-342-3p/-5p were downregulated in PBMCs in T1DM, but not in plasma. PANX2, chemokine receptors CXCR1/2 mRNAs, were increased in PBMCs in T1DM. MiR-342-3p was negatively correlated with TIMP-1, IL-6, IL-8, TNF-α, HbA1c and CXCR2, whilst miR-342-5p was negatively correlated with TIMP-1, IL-6, IL-8 and HbA1c. There was a positive correlation among miR-342-3p, FAA and cEPCs, and between miR-342-5p and cEPCs. ROC curve analyses showed significant downregulation of miR-342-3p/-5p at HbA1c > 46.45 mmol/mol, indicating their potential as biomarkers for subclinical CVD. Our findings validated animal studies and confirmed the proangiogenic properties of miR-342-3p/-5p. MiR-342-3p/-5p-based intervention or monitoring may prove to be beneficial in managing CVD.

[Mechanism of flavonoids of Sophorae Fructus in inhibiting proliferation, migration and invasion of hepatocellular carcinoma cells by regulating LncRNA FBXL19-AS1/miR-342-3p pathway].

The aim of this paper was to investigate the effect of flavonoids of Sophorae Fructus on the proliferation, migration and invasion of hepatocellular carcinoma cells and analyze the regulatory mechanism of LncRNA FBXL19-AS1/miR-342-3 p pathway. MTT assay and plate cloning assay were used to detect the effect of flavonoids of Sophorae Fructus at different concentrations(1, 5, 10 mg·mL~(-1)) on the proliferation of liver cancer Huh7 cells. The effect of flavonoids of Sophorae Fructus on the migration and invasion of Huh7 cells was examined by Transwell chamber assay. qRT-PCR was used to detect the effect of flavonoids of Sophorae Fructus on the expression levels of FBXL19-AS1 and miR-342-3 p in Huh7 cells. The dual luciferase reporter assay was used to detect whether FBXL19-AS1 targeted at miR-342-3 p. The effect on the inhibition of FBXL19-AS1 expression or FBXL19-AS1 overexpression and then the proliferation, migration and invasion of Huh7 cells were examined by the above methods. Gelatin zymography was used to detect the activities of MMP-2 and MMP-9. The expression levels of cyclinD1, p21, MMP-2 and MMP-9 proteins were detected by Western blot. Flavonoids of Sophorae Fructus significantly inhibited the proliferation, migration and invasion of Huh7 cells(P<0.05), promoted the expression of p21 protein(P<0.05), and inhibited the expressions of cyclinD1, MMP-2 and MMP-9(P<0.05) in a dose-dependent manner, and could reduce the activity of MMP-2 and MMP-9(P<0.05). The expression level of FBXL19-AS1 was significantly decreased in Huh7 cells treated with flavonoids of Sophorae Fructus(P<0.05), whereas the expression level of miR-342-3 p was significantly increased(P<0.05). The dual luciferase reporter assay confirmed that FBXL19-AS1 targeted at the inhibition of miR-342-3 p expression. After inhibiting the expression of FBXL19-AS1, the inhibition rate of cell proliferation was significantly increased(P<0.05), the number of cell clone formation was significantly reduced(P<0.05), the number of migrated cells and the number of invasive cells were significantly decreased(P<0.05), and the expression levels of cyclinD1, MMP-2 and MMP-9 were significantly decreased(P<0.05), the activities of MMP-2 and MMP-9 were significantly reduced(P<0.05), while the expression level of p21 protein was significantly increased(P<0.05). The overexpression of FBXL19-AS1 reversed the inhibitory effect of flavonoids of Sophorae Fructus on the proliferation, migration and invasion of Huh7 cells. Flavonoids of Sophorae Fructus could inhibite the proliferation, migration and invasion of hepatoma cells by regulating LncRNA FBXL19-AS1/miR-342-3 p pathway.