Long noncoding RNA LINC00961 inhibits cell invasion and metastasis in human non-small cell lung cancer

Biochemical targets of the micropeptides encoded by lncRNAs

Long non-coding RNAs (lncRNAs) are a group of transcripts longer than 200 nucleotides, which play important roles in regulating various cellular activities by the action of the RNA itself. However, about 40% of lncRNAs in human cells are potentially translated into micropeptides (also referred to as microproteins) usually shorter than 100 amino acids. Thus, these lncRNAs may function by both RNAs directly and their encoded micropeptides. The micropeptides encoded by lncRNAs may regulate transcription, translation, protein phosphorylation or degradation, or subcellular membrane functions. This review attempts to summarize the biochemical targets of the micropeptides-encoded by lncRNAs, which function by both RNAs and micropeptides, and discuss their associations with various diseases and their potentials as drug targets.

CodLncScape Provides a Self-Enriching Framework for the Systematic Collection and Exploration of Coding LncRNAs

Recent studies have revealed that numerous lncRNAs can translate proteins under specific conditions, performing diverse biological functions, thus termed coding lncRNAs. Their comprehensive landscape, however, remains elusive due to this field's preliminary and dispersed nature. This study introduces codLncScape, a framework for coding lncRNA exploration consisting of codLncDB, codLncFlow, codLncWeb, and codLncNLP. Specifically, it contains a manually compiled knowledge base, codLncDB, encompassing 353 coding lncRNA entries validated by experiments. Building upon codLncDB, codLncFlow investigates the expression characteristics of these lncRNAs and their diagnostic potential in the pan-cancer context, alongside their association with spermatogenesis. Furthermore, codLncWeb emerges as a platform for storing, browsing, and accessing knowledge concerning coding lncRNAs within various programming environments. Finally, codLncNLP serves as a knowledge-mining tool to enhance the timely content inclusion and updates within codLncDB. In summary, this study offers a well-functioning, content-rich ecosystem for coding lncRNA research, aiming to accelerate systematic studies in this field.

LncRNAs and PTEN/PI3K signaling: A symphony of regulation in cancer biology

The Emergence of Long Non-coding RNAs (lncRNAs) as Key Regulators in Diverse Biological Processes: A Paradigm Shift in Understanding Gene Expression and its Impact on Cancer. The PTEN/PI3K pathway, a pivotal signaling cascade involved in cancer progression, orchestrates critical cellular functions such as survival, proliferation, and growth. In light of these advances, our investigation delves into the intricate and multifaceted interplay between lncRNAs and the PTEN/PI3K signaling pathway, unearthing previously undisclosed mechanisms that underpin cancer growth and advancement. These elusive lncRNAs exert their influence through direct targeting of the PTEN/PI3K pathway or by skillfully regulating the expression and activity of specific lncRNAs. This comprehensive review underscores the paramount significance of the interaction between lncRNAs and the PTEN/PI3K signaling pathway in cancer biology, unveiling an auspicious avenue for novel diagnostic tools and targeted therapeutic interventions. In this review, we navigate through the functional roles of specific lncRNAs in modulating PTEN/PI3K expression and activity. Additionally, we scrutinize their consequential effects on downstream components of the PTEN/PI3K pathway, unraveling the intricacies of their mutual regulation. By advancing our understanding of this complex regulatory network, this study holds the potential to revolutionize the landscape of cancer research, paving the way for tailored and efficacious treatments to combat this devastating disease.

A Unique Gene Signature Predicting Recurrence Free Survival in Stage IA Lung Adenocarcinoma

Objective

Resected stage IA lung adenocarcinoma (LUAD) has a reported 5-year recurrence free survival (RFS) of 63-81%. A unique gene signature stratifying patients with early stage LUAD as high or low-risk of recurrence would be valuable.

Methods

GEO datasets combining European and North American LUAD patients (n=684) were filtered for stage IA (n=105) to develop a robust signature for recurrence (RFSscore). Univariate Cox proportional hazard regression model was used to assess associations of gene expression with RFS and OS. Leveraging a bootstrap approach of these identified upregulated genes allowed construction of a model which was evaluated by Area Under the Received Operating Characteristics. The optimal signature has RFSscore calculated via a linear combination of expression of selected genes weighted by the corresponding Cox regression derived coefficients. Log-rank analysis calculated RFS and OS. Results were validated using the LUAD TCGA transcriptomic NGS based dataset.

Results

Rigorous bioinformatic analysis identified a signature of 4 genes: KNSTRN, PAFAH1B3, MIF, CHEK1. Kaplan-Meier analysis of stage IA LUAD with this signature resulted in 5-year RFS for low-risk of 90% compared to 53% for high-risk (HR 6.55, 95%CI 2.65-16.18, p-value <0.001), confirming the robustness of the gene signature with its clinical significance. Validation of the signature using TCGA dataset resulted in an AUC of 0.797 and 5-year RFS for low and high-risk stage IA patients being 91% and 67%, respectively (HR 3.44, 95%CI 1.16-10.23, p-value=0.044).

Conclusions

This 4 gene signature stratifies European and North American patients with pathologically confirmed stage IA LUAD into low and high-risk groups for OS and more importantly RFS.

Long non-coding RNAs involved in different steps of cancer metastasis

Non-proteincoding transcripts bearing 200 base pairs known as long non-coding RNAs (lncRNAs) play a role in a variety of molecular mechanisms, including cell differentiation, apoptosis and metastasis. Previous studies have suggested that frequently dysregulated lncRNAs play a crucial role in various aspects of cancer metastasis. Metastasis is the main leading cause of death in cancer. The role of lncRNAs in different stages of metastasis is the subject of this review. Based on in vitro and in vivo investigations on metastasis, we categorized lncRNAs into distinct stages of metastasis including angiogenesis, invasion, intravasation, survival in circulation, and extravasation. The involvement of lncRNAs in angiogenesis and invasion has been extensively studied. Here, we comprehensively discuss the role and functions of these lncRNAs with a particular focus on the molecular mechanisms.

PTEN as a target in melanoma

PTEN is a well-known tumour suppressor protein that is frequently found to be mutated, inactivated or deleted in a wide range of different cancers. Its tumour suppressive properties result predominantly from its inhibitory effects on the PI3K-AKT signalling pathway. In melanoma, numerous different PTEN mutations have been identified in both melanoma cell lines and melanoma tissue. A number of different molecules can act on PTEN to either promote its suppression of melanoma, while other molecules may antagonise PTEN to inhibit its mechanism of action against melanoma. This review will discuss how the interactions of PTEN with other molecules may have a positive or negative impact on melanoma pathogenesis, giving rise to the potential for PTEN-targeted therapies against melanoma.

LncRNA HOXC-AS3 promotes non-small-cell lung cancer growth and metastasis through upregulation of YBX1

NSCLC is common and is the primary cause of cancer-related deaths due to a lack of early diagnosis and its propensity for metastasis. The pathogenesis of NSCLC is still unclear. Here, we explored the molecular mechanisms underlying NSCLC development, focusing on the HOXC-AS3/YBX1/HOXC8 axis. Human NSCLC specimens and cell lines were used. qRT-PCR and western blotting were utilised to examine the levels of HOXC-AS3/YBX1/HOXC8. CCK-8, colony formation, scratch wound healing and Transwell assays were performed to evaluate cancer cell proliferation, migration and invasion. A nude mouse xenograft model was used to examine tumour growth and metastasis in vivo. RNA pull-down, chromatin immunoprecipitation, coimmunoprecipitation and dual-luciferase assays were applied to validate the interactions of HOXC-AS3/YBX1, MDM2/YBX1 and the YBX1/HOXC8 promoter. The levels of HOXC-AS3 and HOXC8 were increased in human NSCLC specimens and cells. Knockdown of HOXC-AS3 suppressed NSCLC cell proliferation, migration and invasion, as well as tumour growth and metastasis in vivo. HOXC-AS3 directly bound to YBX1 to suppress its ubiquitination mediated by MDM2. YBX1 bound to the HOXC8 promoter and enhanced its transcription. Knockdown of HOXC8 inhibited the effects of HOXC-AS3 overexpression on NSCLC. HOXC-AS3 promotes NSCLC growth and metastasis by stabilising YBX1 and thus increasing HOXC8 transcription. Our study indicates that the HOXC-AS3/YBX1/HOXC8 axis could serve as a biomarker for NSCLC diagnosis or as a target for therapy development.

Dysregulated LINC00961 Contributes to the Vitality and Migration of NSCLC Via miR-19a-3p/miR-19b-3p/miR-125b-5p

Accumulating evidence implies that long noncoding RNAs participate in non-small cell lung cancer (NSCLC) tumorigenesis. Our current study synthetically analyzed RNA sequencing data downloaded from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases. We identified LINC00961 significantly downregulated in NSCLC tissues. We explored the LINC00961 expression in NSCLC tumor tissues and cell lines with reverse transcription-quantitative polymerase chain reaction analysis. Lentivirus-mediated infection upregulated the expression of LINC00961 in A549 cells. The proliferation and migration capability were also measured in A549 cells. In addition, we performed luciferase reporter gene assay to investigate whether LINC00961 directly interacts with miR-19a-3p/miR-19b-3p/miR-125b-5p. A nude mice model was used to detect the potential biological process of LINC00961 on tumor growth in vivo. The results showed that LINC00961 was significantly down-egulated in NSCLC tissues and cell lines. LV-LINC00961 effectively increased the expression of LINC00961 and decreased the expression of miR-19a-3p/miR-19b-3p/miR-125b-5p. LINC00961 upregulation remarkably inhibited cell proliferation, migration, and invasion while promoting cell apoptosis in A549 cells. Luciferase reporter gene assay revealed that LINC00961 could directly sponge miR-19a-3p/miR-19b-3p/miR-125b-5p. Moreover, overexpressed miR-19a-3p/miR-19b-3p/miR-125b-5p reversed the effect of LINC00961 on cell function of A549 cells. Western blot assays revealed that LINC00961 could partially act as a tumor suppressor via affecting PI3K-AKT/MAPK/mTOR signaling pathway. In addition, overexpressed LINC00961-inhibited tumor growth was demonstrated in vivo. Overexpression of LINC00961 inhibited cell viability, invasion, and induced apoptosis in NSCLC, potentially via suppressing the expression of miR-19a-3p/miR-19b-3p/miR-125b-5p by targeting PI3K-AKT/MAPK/mTOR signaling pathways, which might provide the potential biomarker for NSCLC diagnosis and therapies.

Dual regulatory actions of LncBMP4 on BMP4 promote chicken primordial germ cell formation

The unique characteristics of chicken primordial germ cells (PGCs) provide potential strategies for transgenic animal generation; however, insufficient PGC availability has limited their application. Regulation of bone morphogenic protein 4 (BMP4), a crucial factor for PGCs formation, may provide new strategies for PGC generation. We here identify a long noncoding RNA (lncRNA) that targets BMP4 (LncBMP4). LncBMP4 has similar functions as BMP4, in that it facilitates the formation and migration of PGCs. LncBMP4 promotes BMP4 expression by adsorbing the miRNA gga-mir-12211, thus reducing its inhibitory effect on BMP4 expression. In addition, the small peptide EPC5 encoded by LncBMP4 promotes the transcription of BMP4. The competing endogenous RNA (ceRNA) effect of LncBMP4 requires N6-methyladenosine (m6A) modification, in a dose-dependent manner, and high levels of m6A modification hinder EPC5 translation. Understanding the molecular mechanisms through which LncBMP4 promotes BMP4 expression during PGC formation may provide new avenues for efficient PGC generation.

LncRNA-encoded microproteins: A new form of cargo in cell culture-derived and circulating extracellular vesicles

Advancements in omics-based technologies over the past few years have led to the discovery of numerous biologically relevant peptides encoded by small open reading frames (smORFs) embedded in long noncoding RNA (lncRNA) transcripts (referred to as microproteins here) in a variety of species. However, the mechanisms and modes of action that underlie the roles of microproteins have yet to be fully characterized. Herein, we provide the first experimental evidence of abundant microproteins in extracellular vesicles (EVs) derived from glioma cancer cells, indicating that the EV-mediated transfer of microproteins may represent a novel mechanism for intercellular communication. Intriguingly, when examining human plasma, 48, 11 and 3 microproteins were identified from purified EVs, whole plasma and EV-free plasma, respectively, suggesting that circulating microproteins are primarily enriched in EVs. Most importantly, the preliminary data showed that the expression profile of EV microproteins in glioma patient diverged from the health donors, suggesting that the circulating microproteins in EVs might have potential diagnostic application in identifying patients with glioma.

Evaluation of the potential role of long non-coding RNA LINC00961 in luminal breast cancer: a case-control and systems biology study

Background

Luminal subtype is the most common subgroup of breast cancer (BC), accounting for more than 70% of this cancer. Long non-coding RNAs (lncRNAs) are a group of RNAs which play critical roles in diverse cellular processes. It is proved that dysregulation of them can contribute to the development of various cancers, including BC. LINC00961 was reported to be downregulated in several cancers, however, its expression level in BC remains largely unknown. The purpose of the present study was to investigate the possible role of LINC00961 in luminal A and B subtypes of BC.

Methods

To obtain novel lncRNAs associated with different cancers and differentially expressed lncRNAs (DElncRNAs) between BC tumor and normal tissues, Lnc2Cancer and GDC databases were used, respectively. After performing literature review, the expression level of the selected lncRNA (LINC00961) was evaluated in 79 luminal A and B BC specimens and adjacent non-cancerous tissues by Quantitative Reverse Transcription PCR (qRT-PCR). LINC00961 expression was also evaluated in two luminal A BC cell lines, compared to a normal breast cell line. The comparison of the differences between tumor and adjacent non-tumor samples was performed by paired sample t-test. Moreover, correlation analysis between LINC00961 expression and clinicopathological features was performed using the chi-square, fisher exact, and independent t-test. In order to investigate the possible roles of LINC00961 in luminal A and B BC, different bioinformatics analyses such as functional annotation of the LINC00961 co-expressed genes and protein–protein interaction (PPI) networks construction were also performed.

Results

LINC00961 was selected as a significant DElncRNA which had not been studied in BC. According to q-RT PCR assay, LINC00961 was downregulated in luminal BC tissues and cell lines. Its expression was correlated with smoking status and the age of menarche in luminal BC patients. Also, the results of the bioinformatics analysis were consistent with the data obtained from q-RT PCR assay. The final results indicated that LINC00961 might be involved in multiple cancer-associated pathways such as chemokine, Ras and PI3K–Akt signaling pathways, GPCR ligand binding, and signal transduction in luminal subtypes of BC. CDH5, GNG11, GNG8, SELL, S1PR1, CCL19, FYN, ACAN, CD3E, ACVRL1, CAV1, and PPARGC1A were identified as the top hub genes of the PPI networks across luminal subgroup.

Conclusion

Our findings suggested that LINC00961 was significantly downregulated in luminal A and B subtypes of BC. Moreover, bioinformatics analysis provided a basis for better identification of the potential role of LINC00961 in luminal subtype of BC.

The small peptide world in long noncoding RNAs

Long noncoding RNAs (lncRNAs) are a group of transcripts that are longer than 200 nucleotides (nt) without coding potential. Over the past decade, tens of thousands of novel lncRNAs have been annotated in animal and plant genomes because of advanced high-throughput RNA sequencing technologies and with the aid of coding transcript classifiers. Further, a considerable number of reports have revealed the existence of stable, functional small peptides (also known as micropeptides), translated from lncRNAs. In this review, we discuss the methods of lncRNA classification, the investigations regarding their coding potential and the functional significance of the peptides they encode.

Long non-coding RNA LINC00641 suppresses non-small-cell lung cancer by sponging miR-424-5p to upregulate PLSCR4

Non-small cell lung cancer (NSCLC) , as the most prevalent type of lung carcinoma with high severity, is of urgent necessity to be investigated for novel therapeutic strategies. Long non-coding RNAs (lncRNAs) are notable for their participation in cancer regulation, and lncRNA long intergenic non-protein coding RNA 641 (LINC00641) has been found to have an inhibitory influence on bladder cancer, but its role in NSCLC has not yet been studied. In this research, we launched an investigation into the biological functions and the underlying molecular mechanisms of LINC00641 in NSCLC. At first, downregulation of LINC00641 was identified in NSCLC cells. Functionally, LINC00641 suppressed cell proliferation and induced cell apoptosis in NSCLC, indicating that LINC00641 exerted tumor-suppressive role in NSCLC. Through mechanism investigation, we determined that LINC00641 acted as a competing endogenous RNA (ceRNA) in NSCLC by sponging miR-424-5p to upregulate phospholipid scramblase (PLSCR4) expression. Further rescue assays indicated that miR-424-5p and PLSCR4 could reverse LINC00641-mediated cellular processes. Taken together, it is demonstrated in our study that LINC00641 can function as a tumor suppressor in NSCLC via a ceRNA network.

Long non-coding RNAs: How to regulate the metastasis of non-small-cell lung cancer

Non–small‐cell lung cancer (NSCLC) has become the most lethal human cancer because of the high rate of metastasis. Hence, clarifying the molecular mechanism underlying NSCLC metastasis is very important to improve the prognosis of patients with NSCLC. Long non‐coding RNAs (LncRNAs) are a class of RNA molecules longer than 200 nucleotides, which can participate in diverse biological processes. About 18% of human LncRNAs were recently found to be associated with tumours. Many studies indicated that aberrant expression of LncRNAs played key roles in the progression and metastasis of NSCLC. According to the function in tumours, LncRNAs can be divided into two classes: oncogenic LncRNAs and tumour‐suppressor LncRNAs. In this review, we summarized the main molecular mechanism of LncRNAs regulating NSCLC metastasis, including three aspects: (a) LncRNAs interact with miRNAs as ceRNAs; (b) LncRNAs bind with target proteins; and (c) LncRNAs participate in the transduction of different signal pathways. Then, LncRNAs can exert their function to regulate the metastasis of NSCLC through influencing the progression of epithelial‐mesenchymal transition (EMT) and the properties of cancer stem cell (CSC). But, it is necessary to do some further research to demonstrate the LncRNAs particular regulatory mechanism of inhibiting the metastasis of NSCLC and explore new drugs targeting LncRNAs.

Emerging role of tumor-related functional peptides encoded by lncRNA and circRNA

Non-coding RNAs do not encode proteins and regulate various oncological processes. They are also important potential cancer diagnostic and prognostic biomarkers. Bioinformatics and translation omics have begun to elucidate the roles and modes of action of the functional peptides encoded by ncRNA. Here, recent advances in long non-coding RNA (lncRNA) and circular RNA (circRNA)-encoded small peptides are compiled and synthesized. We introduce both the computational and analytical methods used to forecast prospective ncRNAs encoding oncologically functional oligopeptides. We also present numerous specific lncRNA and circRNA-encoded proteins and their cancer-promoting or cancer-inhibiting molecular mechanisms. This information may expedite the discovery, development, and optimization of novel and efficacious cancer diagnostic, therapeutic, and prognostic protein-based tools derived from non-coding RNAs. The role of ncRNA-encoding functional peptides has promising application perspectives and potential challenges in cancer research. The aim of this review is to provide a theoretical basis and relevant references, which may promote the discovery of more functional peptides encoded by ncRNAs, and further develop novel anticancer therapeutic targets, as well as diagnostic and prognostic cancer markers.

linc01088 promotes cell proliferation by scaffolding EZH2 and repressing p21 in human non-small cell lung cancer

AIMS

Non-small cell lung cancer (NSCLC), characterized by extensive metastasis and poor prognosis, is the most common type of lung cancer. Dysregulation of certain lncRNAs is known to be linked to the tumorigenesis of NSCLC. However, the specific roles in NSCLC for many other lncRNAs, such as linc01088, remain largely unknown.

MATERIALS AND METHODS

The expression patterns of linc01088, p21 and EZH2 were examined both in NSCLC tissues and cell lines using RT-qPCR assay. CCK-8, colony formation, immunofluorescence staining, and flow cytometry assays were employed to evaluate the effects of linc01088 on NSCLC cell proliferation properties. RNA immunoprecipitation (RIP) assay was performed to determine the direct binding relationship between linc01088 and zeste homolog 2 (EZH2). Western blot and RT-qPCR analysis were performed to assess p21 level within knockdown of either linc01088 or EZH2. Nude mouse subcutaneous NSCLC models were constructed for further validating the effects and mechanisms of linc01088 in vivo.

KEY FINDINGS

linc01088 and EZH2 were highly expressed both in NSCLC tissues and cell lines. Knockdown of linc01088 suppressed the proliferation of NSCLC cells, and prolonged the G1 phase while shortened S and G2-M phases. RIP assay revealed the direct binding relationship between linc01088 and EZH2. Knockdown of either linc01088 or EZH2 induced up-regulation of p21 expression, which subsequently inhibited the tumor growth.

SIGNIFICANCE

We demonstrated that linc01088 could promote cell proliferation via binding with EZH2 to repress p21, which aggravates the tumorigenesis of NSCLC. Therefore, linc01088 might be a potential oncogene and target for novel anti-tumor therapies.

Linc00961 inhibits the proliferation and invasion of skin melanoma by targeting the miR‑367/PTEN axis

Long intergenic noncoding RNA 00961 (Linc00961) has been identified as a tumor suppressor in various types of cancer. However, the critical roles of Linc00961 in the carcinogenesis and progression of skin melanoma (SM) are yet to be fully elucidated. The present study revealed via reverse transcription‑quantitative PCR analysis that Linc00961 was downregulated in the tissues of patients with SM compared with benign nevi, and in A375, A2058 and SK‑MEL‑28 cell lines compared with human melanocytes. Furthermore, overexpression of Linc00961 inhibited cell proliferation, and promoted the apoptosis of A375 and SK‑MEL‑28 cells in vitro and in vivo, as determined by Cell Counting Kit‑8 and flow cytometry assays, and tumor xenograft studies, respectively. Overexpression of Linc00961 also led to an attenuation of the migration and invasive capabilities of A375 and SK‑MEL‑28 cells, measured using Transwell assays. Functionally, it was demonstrated that Linc00961 acted as a competing endogenous RNA (ceRNA) by competitively sponging microRNA‑367 (miR‑367) in A375 and SK‑MEL‑28 cells; restoration of miR‑367 rescued the inhibitory effects of Linc00961 on A375 and SK‑MEL‑28 cells. Finally, it was observed that phosphate and tension homology deleted on chromosome 10 (PTEN), an established target of miR‑367 in A375 and SK‑MEL‑28 cells, was positively regulated by Linc00961, and its inhibition reversed the inhibitory effects of Linc00961 on the proliferation and invasion of A375 and SK‑MEL‑28 cells. Collectively, the present study revealed that Linc00961 was downregulated in SM, and furthermore, Linc00961 was identified as a ceRNA that inhibits the proliferation and invasion of A375 and SK‑MEL‑28 cells by modulating the miR‑367/PTEN axis.

Long non-coding RNA ENST00000500843 is downregulated and promotes chemoresistance to paclitaxel in lung adenocarcinoma

Adenocarcinoma is one of the most common pathological types of human lung cancer and has the highest incidence and mortality rates worldwide. Resistance to paclitaxel (PTX), the standard chemotherapy agent for treatment of lung adenocarcinoma, is a major clinical obstacle. Sensitive markers are urgently required for the diagnosis and characterization of lung cancer, as well as to manage drug resistance. Previous studies have described the activity of long non-coding RNAs (lncRNAs) in human lung cancer and chemotherapy resistance. In previous studies, lncRNA ENST00000500843 was identified to be downregulated in PTX-resistant A549 human lung cancer cells. However, the roles of this lncRNA in the development of lung adenocarcinoma and its mechanism in PTX resistance, to the best of our knowledge, have not been described. In the present study, 56 pairs of lung adenocarcinoma and normal adjacent tissue samples were collected. Reverse transcription-quantitative PCR revealed that the expression levels of lncRNA ENST00000500843 were lower in lung adenocarcinoma tissues and PTX-resistant A549 cells when compared with normal adjacent tissues and A549 cells. Decreased expression levels of lncRNA ENST00000500843 in lung adenocarcinoma tissues were associated with tumor diameter, the degree of pathological differentiation and metastasis of lymph nodes. Additionally, patients with low expression levels of ENST00000500843 exhibited poorer overall survival and progression-free survival rates. Furthermore, the present study demonstrated that knockdown of lncRNA ENST00000500843 with small interfering RNA decreased the likelihood of apoptosis in A549 cells and promoted resistance to PTX. This indicated that lncRNA ENST00000500843 may be a useful diagnostic marker of lung cancer and a good prognostic marker for resistance to treatment with PTX.

STAT3-induced long noncoding RNA LINC00668 promotes migration and invasion of non-small cell lung cancer via the miR-193a/KLF7 axis

Long noncoding RNAs (lncRNAs) have been demonstrated to play significant roles in non-small cell lung cancer (NSCLC) progression. Recently, a newly identified lncRNA, LncRNA LINC00668 (LINC00668), was reported to be involved in the regulation of progression of several tumors. However, the expression pattern and biological function of LINC00668 in NSCLC remains largely unclear. In this study, we found that LINC00668 expression was significantly up-regulated in both NSCLC tissues and cell lines. we also showed that LINC00668 upregulation was induced by transcription factor STAT3. Clinical investigation demonstrated that high expression level of LINC00668 was associated with advanced TNM stage, histological grade and lymph node metastasis. Moreover, multivariate analysis confirmed LINC00668 expression level to be an independent prognostic indicator for overall survival of NSCLC patients. Functional assays indicated that knockdown of LINC00668 suppressed NSCLC cells proliferation, migration and invasion, and promoted apoptosis. Mechanistic studies indicated that LINC00668 is a direct target of miR-193a, leading to down-regulation in the expression of its target gene KLF7. Our findings suggested that STAT3-induced LINC00668 contributed to NSCLC progression through upregulating KLF7 expression by sponging miR-193a, and may serve as a prognostic biomarker and a potential target for NSCLC.

STAT1-avtiviated LINC00961 regulates myocardial infarction by the PI3K/AKT/GSK3β signaling pathway

Myocardial infarction (MI) remains a severe cardiac disease because of its high incidence and mortality worldwide. A growing body of recent investigations have confirmed that LINC00961 acts as a tumor suppressor in diverse malignancies. However, the biological significance of LINC00961 and its molecular mechanism in MI are still elusive. Hypoxia is the leading cause of MI and induces myocardial injury. In this study, we found the upregulated expression of LINC00961 in cardiomyocytes H9c2 after hypoxia treatment. Knockdown of LINC00961 ameliorated hypoxia-induced cell injury by facilitating cell viability while repressing cell apoptosis. The significant increase of signal transducer and activator of transcription 1 (STAT1) expression and phosphorylation levels was observed in hypoxia-induced cells and proved to exacerbate hypoxia injury. In addition, STAT1 transcriptionally activated LINC00961 by binding to LINC00961 promoter. Furthermore, our results validated that suppressing LINC00961 contributed to the remarkable diminution in the phosphorylation levels of phosphoinositide 3-kinases (PI3K), AKT, and glycogen synthase kinase-3β (GSK3β). Inhibition of PI3K/AKT signaling or GSK3β pathway rescued the effects of LINC00961 knockdown on the hypoxia-induced injury of cardiomyocytes. Namely, we concluded that STAT1-avtiviated LINC00961 accelerated MI via the PI3K/AKT/GSK3β pathway, which may provide clues for the treatment of patients with MI.

Small regulatory polypeptide of amino acid response negatively relates to poor prognosis and controls hepatocellular carcinoma progression via regulating microRNA-5581-3p/human cardiolipin synthase 1

Hepatocellular carcinoma (HCC) is one of the most common malignancies with extremely high rates of occurrence and death. Long noncoding RNAs (lncRNAs) have been increasingly revealed to participate in tumorigenesis and development of multiple human cancers, including HCC. LINC00961 is a novel lncRNA which has been uncovered as a tumor suppressor in lung cancer and glioma. However, the role of LINC00961 in HCC has never been probed yet. Herein, we revealed a marked downregulation of LINC00961 in HCC tissues and cell lines. Correlation of low LINC00961 expression with poor outcomes in patients with HCC suggested LINC00961 as an independent predictor for HCC prognosis. Functionally, LINC00961 overexpression obviously inhibited cell proliferation, migration, and invasion in HCC cells. Mechanistically, LINC00961 regulated cardiolipin synthase 1 (CRLS1) expression via sponging miR-5581-3p. Importantly, both miR-5581-3p upregulation and CRLS1 inhibition led to an acceleration in cellular processes in HCC cells. At length, the rescue assays suggested that LINC00961 functioned in HCC through the miR-5581-3p/CRLS1 axis. On the whole, our findings disclosed that LINC00961 played a suppressive role in HCC progression via modulating miR-5581-3p/CRLS1, thus providing a potentially effective target for the prognosis and treatment of patients with HCC.

LINC00961 restrains cancer progression via modulating epithelial-mesenchymal transition in renal cell carcinoma

Recently, long noncoding RNA have been identified as new gene regulators and prognostic biomarkers in various cancers, including renal cell carcinoma (RCC). The expression and biological roles of LINC00961 have been reported in many human cancers. However, up to date, no study of LINC00961 has been shown in RCC. Currently, we aimed to investigate the function of LINC00961 in RCC progression. Interestingly, we observed that LINC00961 could act as a novel biomarker in predicting the diagnosis of RCC. Then, we found that LINC00961 was greatly downregulated in RCC cell lines (Caki-1, Caki-2, 786-O, A498, and ACHN cells) compared with normal renal cell lines (HK-2 cells). Then, 786-O cells and ACHN cells were infected with LV-LINC00961. As displayed in our current study, LINC00961 overexpression could obviously suppress the proliferation and survival of RCC cells in vitro. In addition, RCC cell apoptosis was greatly induced and cell cycle progression was blocked in G1 phase by upregulation of LINC00961 in 786-O cells and ACHN cells. Subsequently, we found that LV-LINC00961 was able to restrain RCC cell migration and cell invasion capacity. Meanwhile, the messenger RNA and protein expression levels of epithelial-mesenchymal transition (EMT)-associated markers Slug and N-cadherin in RCC cell lines were dramatically inhibited by overexpressing LINC00961. Finally, the in vivo experiment was carried out and we observed that LINC00961 could inhibit RCC development through modulating EMT process. Taken these together, it was indicated in our study that LINC00961 was involved in RCC progression through targeting EMT pathway.

Long non-coding RNA SNHG15 promotes CDK14 expression via miR-486 to accelerate non-small cell lung cancer cells progression and metastasis

Long non-coding RNAs (lncRNAs) have been validated to play important role in multiple cancers, including non-small cell lung cancer (NSCLC). In present study, our team investigate the biologic role of SNHG15 in the NSCLC tumorigenesis. LncRNA SNHG15 was significantly upregulated in NSCLC tissue samples and cells, and its overexpression was associated with poor prognosis of NSCLC patients. In vitro, loss-of-functional cellular experiments showed that SNHG15 silencing significantly inhibited the proliferation, promoted the apoptosis, and induced the cycle arrest at G0//G1 phase. In vivo, xenograft assay showed that SNHG15 silencing suppressed tumor growth of NSCLC cells. Besides, SNHG15 silencing decreased CDK14 protein expression both in vivo and vitro. Bioinformatics tools and luciferase reporter assay confirmed that miR-486 both targeted the 3'-UTR of SNHG15 and CDK14 and was negatively correlated with their expression levels. In summary, our study conclude that the ectopic overexpression of SNHG15 contribute to the NSCLC tumorigenesis by regulating CDK14 protein via sponging miR-486, providing a novel insight for NSCLC pathogenesis and potential therapeutic strategy for NSCLC patients.

Long noncoding RNA LINC00961 inhibits cell proliferation and induces cell apoptosis in human non-small cell lung cancer

Long noncoding RNAs (LncRNAs) have been identified in multiple human cancer types, including lung cancer. An increasing number of studies have indicated that lncRNAs can function as important gene regulators. However, the biological mechanism of LINC00961 in lung cancerremains poorly understood. In our current study, we recognized lncRNA LINC00961, and we observed that it was significantly reduced in human non-small cell lung cancer (NSCLC) tissues. LINC00961 was elevated by infecting LV-LINC00961, while decreased by LV-shLINC00961 in H226 and A549 cells. Furthermore, it was shown that LINC00961 overexpression greatly inhibited lung cancer cell proliferation, whereas downregulated LINC00961 induced cell proliferation. In addition, further experiments showed that restoration of LINC00961 could dramatically increase apoptotic ratios of NSCLC H226 and A549 cells, and knockdown of LINC00961 exhibited an opposite effect. Moreover, Western blot analysis showed that upregulation of LINC00961 repressed proliferating cell nuclear antigen expression and increased Bax expression, indicating that it acts as an important pro-apoptosis gene. Conversely, inhibition of LINC00961 induced proliferating cell nuclear antigen expression and restrained Bax protein levels. Taking these together, LINC00961 might play a tumor suppressive role in NSCLC progression, and it could serve as a novel prognostic biomarker in NSCLC diagnosis and treatment.