Long intergenic non-protein coding RNA 511 promotes the progression of osteosarcoma cells through sponging microRNA 618 to upregulate the expression of maelstrom

The emerging roles of LINC00511 in breast cancer development and therapy

Breast cancer (BC) is associated with malignant tumors in women worldwide with persistently high incidence and mortality rates. The traditional therapies including surgery, chemotherapy, radiotherapy and targeted therapy have certain therapeutic effects on BC patients, but acquired drug resistance can lead to tumor recurrence and metastasis. This remains a clinical challenge that is difficult to solve during treatment. Therefore, continued research is needed to identify effective targets and treatment methods, to ultimately implement personalized treatment strategies. Several studies have implicated that the long non-coding RNA LINC00511 is closely linked to the occurrence, development and drug resistance of BC. Here we will review the structure and the mechanisms of action of lnc RNA LINC00511 in various cancers, and then explore its expression and its related regulatory mechanisms during BC. In addition, we will discuss the biological functions and the potential clinical applications of LINC00511 in BC.

Osteosarcoma in a ceRNET perspective

Osteosarcoma (OS) is the most prevalent and fatal type of bone tumor. It is characterized by great heterogeneity of genomic aberrations, mutated genes, and cell types contribution, making therapy and patients management particularly challenging. A unifying picture of molecular mechanisms underlying the disease could help to transform those challenges into opportunities.This review deeply explores the occurrence in OS of large-scale RNA regulatory networks, denominated "competing endogenous RNA network" (ceRNET), wherein different RNA biotypes, such as long non-coding RNAs, circular RNAs and mRNAs can functionally interact each other by competitively binding to shared microRNAs. Here, we discuss how the unbalancing of any network component can derail the entire circuit, driving OS onset and progression by impacting on cell proliferation, migration, invasion, tumor growth and metastasis, and even chemotherapeutic resistance, as distilled from many studies. Intriguingly, the aberrant expression of the networks components in OS cells can be triggered also by the surroundings, through cytokines and vesicles, with their bioactive cargo of proteins and non-coding RNAs, highlighting the relevance of tumor microenvironment. A comprehensive picture of RNA regulatory networks underlying OS could pave the way for the development of innovative RNA-targeted and RNA-based therapies and new diagnostic tools, also in the perspective of precision oncology.

YY1-induced lncRNA00511 promotes melanoma progression via the miR-150-5p/ADAM19 axis

Increasing evidence indicates that long noncoding RNAs (lncRNAs) are therapeutic targets and key regulators of tumors development and progression, including melanoma. Long intergenic non-protein-coding RNA 511 (LINC00511) has been demonstrated as an oncogenic molecule in breast, stomach, colorectal, and lung cancers. However, the precise role and functional mechanisms of LINC00511 in melanoma remain unknown. This study confirmed that LINC00511 was highly expressed in melanoma cells (A375 and SK-Mel-28 cells) and tissues, knockdown of LINC00511 could inhibit melanoma cell migration and invasion, as well as the growth of subcutaneous tumor xenografts in vivo. By using Chromatin immunoprecipitation (ChIP) assay, it was demonstrated that the transcription factor Yin Yang 1 (YY1) is capable of binding to the LINC00511 promoter and enhancing its expression in cis. Further mechanistic investigation showed that LINC00511 was mainly enriched in the cytoplasm of melanoma cells and interacted directly with microRNA-150-5p (miR-150-5p). Consistently, the knockdown of miR-150-5p could recover the effects of LINC00511 knockdown on melanoma cells. Furthermore, ADAM metallopeptidase domain expression 19 (ADAM19) was identified as a downstream target of miR-150-5p, and overexpression of ADAM19 could promote melanoma cell proliferation. Rescue assays indicated that LINC00511 acted as a competing endogenous RNA (ceRNA) to sponge miR-150-5p and increase the expression of ADAM19, thereby activating the PI3K/AKT pathway. In summary, we identified LINC00511 as an oncogenic lncRNA in melanoma and defined the LINC00511/miR-150-5p/ADAM19 axis, which might be considered a potential therapeutic target and novel molecular mechanism the treatment of patients with melanoma.

The Intergenic Type LncRNA (LINC RNA) Faces in Cancer with In Silico Scope and a Directed Lens to LINC00511: A Step toward ncRNA Precision

BACKGROUND

Long intergenic non-coding RNA, is one type of lncRNA, exerting various cellular activities, as does ncRNA, including the regulation of gene expression and chromatin remodeling. The abnormal expression of lincRNAs can induce or suppress carcinogenesis.

MAIN BODY

LincRNAs can regulate cancer progression through different mechanisms and are considered as potential drug targets. Genetic variations such as single nucleotide polymorphisms (SNPs) in lincRNAs may affect gene expression and messenger ribonucleic acid (mRNA) stability. SNPs in lincRNAs have been found to be associated with different types of cancer, as well. Specifically, LINC00511 has been known to promote the progression of multiple malignancies such as breast cancer, colorectal cancer, lung cancer, hepatocellular carcinoma, and others, making it a promising cancer prognostic molecular marker.

CONCLUSION

LincRNAs have been proved to be associated with different cancer types through various pathways. Herein, we performed a comprehensive literature and in silico databases search listing lncRNAs, lincRNAs including LINC00511, lncRNAs' SNPs, as well as LINC00511 SNPs in different cancer types, focusing on their role in various cancer types and mechanism(s) of action.

MAEL facilitates metabolic reprogramming and breast cancer progression by promoting the degradation of citrate synthase and fumarate hydratase via chaperone-mediated autophagy

Metabolic reprogramming is a hallmark of cancer. Several studies have shown that inactivation of Krebs cycle enzymes, such as citrate synthase (CS) and fumarate hydratase (FH), facilitates aerobic glycolysis and cancer progression. MAEL has been shown to play an oncogenic role in bladder, liver, colon, and gastric cancers, but its role in breast cancer and metabolism is still unknown. Here, we demonstrated that MAEL promoted malignant behaviours and aerobic glycolysis in breast cancer cells. Mechanistically, MAEL interacted with CS/FH and HSAP8 via its MAEL domain and HMG domain, respectively, and then enhanced the binding affinity of CS/FH with HSPA8, facilitating the transport of CS/FH to the lysosome for degradation. MAEL-induced degradation of CS and FH could be suppressed by the lysosome inhibitors leupeptin and NH₄ Cl, but not by the macroautophagy inhibitor 3-MA or the proteasome inhibitor MG132. These results suggested that MAEL promoted the degradation of CS and FH via chaperone-mediated autophagy (CMA). Further studies showed that the expression of MAEL was significantly and negatively correlated with CS and FH in breast cancer. Moreover, overexpression of CS or/and FH could reverse the oncogenic effects of MAEL. Taken together, MAEL promotes a metabolic shift from oxidative phosphorylation to glycolysis by inducing CMA-dependent degradation of CS and FH, thereby promoting breast cancer progression. These findings have elucidated a novel molecular mechanism of MAEL in cancer.

Differential effects of the LncRNA RNF157-AS1 on epithelial ovarian cancer cells through suppression of DIRAS3- and ULK1-mediated autophagy

Analyses of several databases showed that the lncRNA RNF157 Antisense RNA 1 (RNF157-AS1) is overexpressed in epithelial ovarian cancer (EOC) tissues. In our study, suppressing RNF157-AS1 strikingly reduced the proliferation, invasion, and migration of EOC cells compared with control cells, while overexpressing RNF157-AS1 greatly increased these effects. By RNA pulldown assays, RNA binding protein immunoprecipitation (RIP) assays, and mass spectrometry, RNF157-AS1 was further found to be able to bind to the HMGA1 and EZH2 proteins. Chromatin immunoprecipitation (ChIP) assays showed that RNF157-AS1 and HMGA1 bound to the ULK1 promoter and prevented the expression of ULK1. Additionally, RNF157-AS1 interacted with EZH2 to bind to the DIRAS3 promoter and diminish DIRAS3 expression. ULK1 and DIRAS3 were found to be essential for autophagy. Combination autophagy inhibitor and RNF157-AS1 overexpression or knockdown, a change in the LC3 II/I ratio was found using immunofluorescence (IF) staining and western blot (WB) analysis. The autophagy level also was confirmed by autophagy/cytotoxicity dual staining. However, the majority of advanced EOC patients require platinum-based chemotherapy, since autophagy is a cellular catabolic response to cell stress. As a result, RNF157-AS1 increased EOC cell sensitivity to chemotherapy and death under cis-platinum (DDP) treatment by suppressing autophagy, as confirmed by cell count Kit-8 (CCK8) assays, flow cytometry, and autophagy/cytotoxicity dual staining. Therefore, the OS and PPS times were longer in EOC patients with elevated RNF157-AS1 expression. RNF157-AS1-mediated autophagy has potential clinical significance in DDP chemotherapy for EOC patients.

A review on the role of LINC00511 in cancer

Long Intergenic Non-Protein Coding RNA 511 (LINC00511) is an RNA gene being mostly associated with lung cancer. Further assessments have shown dysregulation of this lncRNA in a variety of cancers. LINC00511 has interactions with hsa-miR-29b-3p, hsa-miR-765, hsa-mir-150, miR-1231, TFAP2A-AS2, hsa-miR-185-3p, hsa-miR-29b-1-5p, hsa-miR-29c-3p, RAD51-AS1 and EZH2. A number of transcription factors have been identified that regulate expression of LINC00511. The current narrative review summarizes the role of LINC00511 in different cancers with an especial focus on its prognostic impact in human cancers.

LINC00511 promotes cervical cancer progression by regulating the miR-497-5p/MAPK1 axis

BACKGROUND

Long non-coding RNA (lncRNA) exhibits a crucial role in multiple human malignancies. The expression of lncRNA LINC00511, reportedly, is aberrantly up-regulated in several types of tumors. Our research was aimed at deciphering the role and mechanism of LINC00511 in the progression of cervical cancer (CC).

METHOD

Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to quantify the expression levels of LINC00511, miR-497-5p and MAPK1 mRNA in CC tissues and cell lines. Cell counting kit-8 (CCK-8), 5-bromo-2'-deoxyuridine (BrdU) and Transwell assays were conducted for detecting the proliferation, migration and invasion of CC cells. Dual-luciferase reporter gene experiments were performed to verify the targeting relationships amongst LINC00511, miR-497-5p and MAPK1. Besides, MAPK1 expression in CC cells was detected via Western blot after LINC00511 and miR-497-5p were selectively regulated.

RESULTS

Up-regulation of LINC00511 expression in CC tissues and cell lines was observed, which was in association with tumor size, clinical stage and lymph node metastasis of the patients. LINC00511 overexpression facilitated the proliferation, migration and invasion of CC cells, while opposite effects were observed after knockdown of LINC00511. Mechanistically, LINC00511 was capable of targeting miR-497-5p and up-regulating MAPK1 expression.

CONCLUSION

LINC00511/miR-497-5p/MAPK1 axis regulates CC progression.

CTBP1-AS2 promoted non-small cell lung cancer progression via sponging the miR-623/MMP3 axis

Mounting evidence indicates that lncRNAs (long noncoding RNAs) are involved in the initiation and development of tumors, including non-small cell lung cancer (NSCLC). However, the involvement of C-terminal binding protein-antisense RNA 2 (CTBP1-AS2) in NSCLC remains to be studied. RT-qPCR was carried out to detect CTBP1-AS2 and miR-623 expression in NSCLC cells and tissues. CCK-8 and flow cytometry were performed to measure cell proliferation and cell cycle progression. Luciferase reporter analysis was performed to study the potential target of CTBP1-AS2. We found that CTBP1-AS2 expression was upregulated in NSCLC cells (SPC-A1, A549, H23, and H1299) compared to 16HBE cells. We demonstrated that the CTBP1-AS2 level was higher in NSCLC specimens than in paired non-tumor specimens. Elevated expression of CTBP1-AS2 increased cell growth and induced cell cycle progression and epithelial-mesenchymal transition (EMT). We also found that ectopic expression of CTBP1-AS2 inhibited miR-623 expression. MMP3 was a direct target of miR-623, and luciferase reporter assays suggested that miR-623 overexpression suppressed the luciferase expression driven by the MMP3 wild-type reporter but not the mutant reporter. Overexpression of miR-623 suppressed MMP3 expression in A549 cells, and overexpression of CTBP1-AS2 increased MMP3 expression in A549 cells. Moreover, the miR-623 level was lower in NSCLC specimens than in paired non-tumor specimens, and CTBP1-AS2 expression was negatively correlated with miR-623 expression in NSCLC samples. Furthermore, overexpression of CTBP1-AS2 enhanced cell growth, cell cycle progression, and EMT progression by modulating MMP3 expression.

The role of long intergenic noncoding RNA 00511 in malignant tumors: a meta-analysis, database validation and review

Increasing studies suggested that long intergenic noncoding RNA 00511 (LINC00511) could facilitate the progression of various malignancies and correlates with prognosis of patients with malignant tumors. However, its clinical significance is still not completely clarified. Therefore, we performed a meta-analysis and bioinformatics analysis to further evaluate the correlation of LINC00511 expression level with prognosis and metastasis in patients with tumors. The pooled hazard ratio (HR) with 95% confidence interval (CI) was used to evaluate the prognostic significance of LINC00511 expression level. The pooled odds ratio (OR) with 95% CI was applied to assess the association between LINC00511 expression level and tumor metastasis. A total of 12 studies involving 1040 tumor patients were included in this meta-analysis. The pooled analyses suggested that higher LINC00511 expression level correlated with worse overall survival (OS) (HR = 1.93, 95% CI 1.49–2.49, P < 0.001) and higher incidence of lymph node metastasis (OR = 3.07, 95% CI 2.23–4.23, P < 0.001). Additionally, bioinformatics analysis based on TCGA datasets also showed that increased LINC00511 expression level may predict poor OS and disease-free survival (DFS) in patients with malignant tumors. Taken together, our finding suggested that high LINC00511 expression level may be correlated with poor prognosis and high incidence of metastasis. Nevertheless, further large-scale and high-quality studies are needed to validate our findings.

Circulating miR-618 Has Prognostic Significance in Patients with Metastatic Colon Cancer

The present study evaluated the prognostic role of circulating miRNA-618 in patients with metastatic colon cancer (mCC) and whether miR-618 gene rs2682818 single nucleotide polymorphisms (SNP) are associated with colon cancer susceptibility and expression levels of mature miR-618. In total, 104 patients with mCC before starting the chemotherapy were investigated. The expression status of circulating miR-618 in mCC was evaluated by quantitative PCR. TaqMan PCR assay was used for rs2682818 SNP genotyping. miR-618 was overexpressed in serum of mCC patients. Patients with high and intermediate expression of miR-618 had a significantly longer mean overall survival (OS) of 21 months than patients with low expression—16 months. In addition, multivariate Cox regression analysis confirmed the association between high/intermediate levels of miRNA-618 and longer OS, HR = 0.51, 95% CI: 0.30–0.86, p = 0.012. miR-618 rs2682818 SNP significantly decreased the risk of colon cancer susceptibility in both heterozygous codominant (AC vs. CC, OR = 0.39, 95% CI: 0.17–0.88, p = 0.024) and overdominant (AC vs. CC + AA, OR = 0.37, 95% CI: 0.16–0.85, p = 0.018) genetic models. Our data suggest that circulating miRNA-618 could be useful as a prognostic biomarker in mCC. Patients harboring AC rs2682818 genotype have a decreased risk for colon cancer in comparison with patients with CC and AA genotypes.

The role of cigarette smoke-induced pulmonary vascular endothelial cell apoptosis in COPD

Chronic obstructive pulmonary disease (COPD) is one of the most common chronic respiratory diseases with high morbidity and mortality. It has become the fifth most burdened and the third most deadly disease in the global economy and increases year by year. The prevention and treatment of COPD are urgent. Smoking is the main and most common risk factor for COPD. Cigarette smoke (CS) contains a large number of toxic substances, can cause a series of changes in the trachea, lung tissue, pulmonary blood vessels, and promotes the occurrence and development of COPD. In recent years, the development of epigenetics and molecular biology have provided new guidance for revealing the pathogenesis, diagnosis, and treatment of diseases. The latest research indicates that pulmonary vascular endothelial cell apoptosis initiates and participates in the pathogenesis of COPD. In this review, we summarize the current research on the epigenetic mechanisms and molecular biology of CS-induced pulmonary vascular endothelial cell apoptosis in COPD, providing a new research direction for pathogenesis of COPD and a new target for the diagnosis, treatment, and prevention of COPD.

Long Non-Coding RNA HCG11 Aggravates Osteosarcoma Carcinogenesis via Regulating the microRNA-579/MMP13 Axis

Background

Previous studies have suggested that long non-coding RNAs (lncRNAs) were involved in tumorigenesis of various human carcinomas, including osteosarcoma (OS). However, the expression and specific role of lncRNA HLA complex group 11 (HCG11) in OS remain unknown. The current study aimed at revealing the role of lncRNA HCG11 and its related mechanism in OS.

Methods

lncRNA HCG11 expression was verified with RT-qPCR followed by sub-localization determination. LncRNA-microRNA (miRNA) and miRNA–mRNA interactions were predicted by online bioinformatics websites. Validation was performed using dual-luciferase reporter gene assays, and gain- and loss-of-function experiments. The effects of lncRNA HCG11, miR-579 and matrix metalloproteinase 13 (MMP13) on the proliferation, migration and invasion, epithelial-mesenchymal transition (EMT) of OS cells were detected using cell counting kit-8 (CCK-8), Transwell assays and Western blot analysis.

Results

LncRNA HCG11 overexpression was observed in OS tissues and cell lines. Downregulation of lncRNA HCG11/MMP13 or overexpression of miR-579 blocked the progression of OS cells. LncRNA HCG11, which is located in the cytoplasm, promoted MMP13 expression through sponging miR-579.

Conclusion

LncRNA HCG11 might be beneficial for OS aggravation via sponging miR-579 and facilitating MMP13 expression, which represents a candidate biomarker and target for OS therapy.

Prognostic significance of long intergenic non-protein-coding RNA 511expression in malignant tumors: A systematic review and meta-analysis

BACKGROUND

A growing number of studies have suggested that the Long intergenic noncoding RNA 00511 (LINC00511) is aberrantly expressed in multiple malignancies and is related to patient survival. Herein, we conducted a systematic review and meta-analysis to comprehensively evaluate the prognostic significance of LINC00511 in human malignancies.

METHODS

Eligible studies published by March 11, 2020 were identified in 4 electronic databases including PubMed, EMBASE, Web of Science, and the Chinese National Knowledge Infrastructure. Hazard ratios and 95% confidence intervals (CIs) were used to evaluate the prognostic significance of LINC00511 expression in malignant tumors. The association between LINC00511 expression and cancer clinicopathologic features were assessed using Odds ratios (ORs) and CIs.

RESULTS

A total of 13 studies, comprising 1,053 patients, were included in the meta-analysis. The calculated hazard ratio was 2.00 (95% CI: 1.59-2.52, P < .000), suggesting that higher LINC00511 expression could predict poorer overall survival in patients with malignancies. Additionally, our statistical analysis indicated that elevated LINC00511 expression closely associated with bigger tumors (OR = 2.92, 95% CI 1.65-5.18, P < .000), higher incidence of lymph node metastasis (OR = 3.46, 95% CI 2.11-5.66, P < .000) and distant metastasis (OR = 2.40, 95% CI 1.14-5.05, P = .02), poorer differentiation (OR = 1.55, 95% CI 1.11-2.16, P = .01), as well as more advanced TNM stage (OR = 3.90, 95% CI 2.70-5.63, P < .000).

CONCLUSIONS

High LINC00511 expression may predict unfavorable prognosis in patients with malignancies. It should be further explored as a potential prognostic and therapeutic biomarker for human cancer.

ELF1-activated FOXD3-AS1 promotes the migration, invasion and EMT of osteosarcoma cells via sponging miR-296-5p to upregulate ZCCHC3

Osteosarcoma (OS) is a malignant carcinoma often occurring in adolescents. The critical function of long non-coding RNAs (lncRNAs) in cancer arouses increasing attention. Nevertheless, the specific function of FOXD3 Antisense RNA 1 (FOXD3-AS1) in OS has not been understood yet. In this research, FOXD3-AS1 showed strengthened level in OS specimens and cell lines, and its deficiency restrained cell migration, invasion and epithelial-to-mesenchymal transition (EMT) in OS. Then, we confirmed the interaction of FOXD3-AS1 with microRNA-296-5p (miR-296-5p) and that miR-296-5p overexpression blocked OS cell migration, invasion and EMT. Besides, miR-296-5p targeted zinc finger CCHC-type containing 3 (ZCCHC3), and FOXD3-AS1 released ZCCHC3 via sequestering miR-296-5p. Moreover, rescue assays delineated that ZCCHC3 upregulation neutralized the inhibitory effect of FOXD3-AS1 depletion on in vitro behaviors and in vivo tumorigenesis in OS. In addition, E74 like ETS transcription factor 1 (ELF1) stimulated FOXD3-AS1 transcription, and ELF1 silence-suppressed malignant phenotypes of OS cells were offset by FOXD3-AS1 upregulation. Overall, present work elucidated that ELF1-activated FOXD3-AS1 aggravated cell migration, invasion and EMT in OS via absorbing miR-296-5p to augment ZCCHC3 expression, which might provide potential guidance for researchers to find effective targets for OS treatment.

Long Intergenic Non-protein Coding RNA 511 in Cancers

Background: Long intergenic non-protein coding RNA 511 (LINC00511) is upregulated in diverse cancers and involved in prognosis. This study aimed to evaluate the prognostic profile of LINC00511 in cancer patients.

Methods: Published studies evaluating the prognosis of LINC00511 in patients with different cancers were identified from Medline, Embase, and Web of Science. Analysis of the association between LINC00511 and clinicopathological characteristics was conducted. GEPIA was used to validation and functional analysis and LnCeVar was used to get genomic variations.

Results: We eventually included 9 studies, and the combined results showed LINC00511 was significantly associated with decreased OS (HR = 3.18, 95% CI = 2.29 ~ 4.42, P < 0.001) albeit with mild heterogeneity (I² = 58.1%, P_h = 0.014), similarly in cancer type subgroups: breast cancer, digestive system cancer, and cervical cancer (all P < 0.001). There is no publication bias and meta-regression indicated follow-up time maybe heterogeneity of the results (P = 0.008). Additionally, LINC00511 appeared to be correlated with age, clinical stage, tumor size, and lymph node metastasis. Those findings were confirmed in GEPIA. Through LnCeVars, gene ontology and functional pathways were enriched, and dysregulated hallmarks and related ceRNA network of LINC00511 were disturbed.

Conclusions: LINC00511 could be predictive of poor OS and lymph node metastasis in multiple cancers, in another word, LINC00511 serves as an unfavorable prognostic factor, and its mechanism is related to ceRNA.

DDX11-AS1 contributes to osteosarcoma progression via stabilizing DDX11

Increasing evidence has uncovered that long noncoding RNAs (lncRNAs) play extremely important roles in numerous steps of gene regulation concerning the progression of tumors. Defined as a kind of lncRNA, DDX11-AS1 has been considered to be closely related to the tumorigenesis of malignancies. Nevertheless, the underlying regulatory role of it in osteosarcoma remains to be analyzed and elucidated. In this research, a dramatically upregulated expression of DDX11-AS1 was detected in osteosarcoma cells. Loss-of-function assays revealed that decreased expression of DDX11-AS1 impaired osteosarcoma cell proliferation, metastasis as well as epithelial-mesenchymal transition (EMT) process. Afterwards, molecular mechanism tests validated that DDX11-AS1 could sponge miR-873-5p to upregulate DDX11 expression in osteosarcoma. Additionally, functional tests delineated that upregulation of miR-873-5p inhibited cell proliferation, metastasis as well as EMT process in osteosarcoma progression. Further, DDX11-AS1 was verified to regulate the mRNA stability of DDX11 through binding with IGF2BP2 in osteosarcoma. Final rescue tests in vitro and in vivo further elucidated that DDX11 overexpression could reversed the DDX11-AS1 downregulation-mediated effect on osteosarcoma progression. To sum up, DDX11-AS1 contributes to osteosarcoma progression via stabilizing DDX11.