Long non-coding RNA AFAP1-AS1 plays an oncogenic role in promoting cell migration in non-small cell lung cancer

A Comparative Meta-Analysis on the Association of lncRNAs MALAT1, HOTAIR, and AFAP1-AS1 With the Risk of Developing Lymph Node Metastasis in Lung Cancer

BACKGROUND

Numerous studies have demonstrated the significance of long noncoding RNA (lncRNA) in the development of cancer metastasis. The expression levels of many lncRNAs are elevated in metastatic lung cancer patients compared to non-metastatic lung cancer patients.

OBJECTIVES

The primary objective of the study was to investigate the association between the expression levels of three lncRNAs (MALAT1, HOTAIR, and AFAP1-AS1) and lymph node metastasis (LNM) of lung cancer.

METHODS

Cell Press, PubMed, SpringerLink, Web of Science, and Google Scholar were explored to perform the literature search. After screening 1862 articles, 66 English-language articles were selected based on the inclusion and exclusion criteria. From those articles, 17 publications comprising 1622 lung cancer patients were chosen for statistical analyses as well as quality assessment tests.

RESULTS

Forest plot analysis revealed that there was a significant difference in the incidence of LNM between the high and low MALAT1 expression groups (OR = 3.21, 95% CI: 1.34-7.67; random effects model). Significant differences were also observed in the incidence of LNM between patients with high and low HOTAIR expression levels (OR = 4.17, 95% CI: 1.47-11.82; random effects model). The expression level of AFAP1-AS1 was found to be significantly associated with LNM in lung cancer (OR = 2.31, 95% CI: 1.39-3.85, random effects model). Additional analysis from GEPIA and GEO databases revealed that the expression levels of these lncRNAs vary according to the type of tumor tissue, organ of metastasis, and cancer stage. However, these databases show that the result for AFAP1-AS1 is the most aligned with the meta-analysis's findings. Furthermore, several quality assessment tests showed that the AFAP1-AS1 studies are more reliable compared to the studies of other lncRNAs.

CONCLUSION

This study suggested that LNM in lung cancer patients is associated mostly with an elevated AFAP1-AS1 lncRNA level among the pool of three lncRNAs analyzed. Before these results can be implemented in a clinical setting, it is essential to conduct further validation and undertake comprehensive analysis to ensure robustness and reliability.

LncRNA AFAP1-AS1 mediates breast cancer cell proliferation and migration through the miR-21/PTEN axis

LncRNAs play various effects, mostly by sponging with miRNAs. Based on public databases integrating bioinformatics analyses and further validation in breast cancer (BC) tissue and cell lines, the effect of lncRNA AFAP1-AS1 on breast cancer cell proliferation and migration was verified. It might work via the miR-21/PTEN axis. The expression of AFAP1-AS1, which was significantly upregulated in BC tissues and cell lines, was correlated with old age and lymph node metastasis of patients with BC. Knockdown of AFAP1-AS1 inhibited the proliferation and migration of BC cells in vitro and in vivo. And downregulated miR-21 expression and upregulated PTEN expression additionally. Mechanistically, the knockdown of lncRNA AFAP1-AS1 upregulated PTEN expression and consequently attenuated miR-21-mediated enhanced BC cell proliferation and migration. LncRNA AFAP1-AS1 is a potential prognostic biomarker for BC patients.

From diagnosis to therapy: The transformative role of lncRNAs in eye cancer management

The genomic era has brought about a transformative shift in our comprehension of cancer, unveiling the intricate molecular landscape underlying disease development. Eye cancers (ECs), encompassing diverse malignancies affecting ocular tissues, pose distinctive challenges in diagnosis and management. Long non-coding RNAs (lncRNAs), an emerging category of non-coding RNAs, are pivotal actors in the genomic intricacies of eye cancers. LncRNAs have garnered recognition for their multifaceted roles in gene expression regulation and influence on many cellular processes. Many studies support that the lncRNAs have a role in developing various cancers. Recent investigations have pinpointed specific lncRNAs associated with ECs, including retinoblastoma and uveal melanoma. These lncRNAs exert control over critical pathways governing tumor initiation, progression, and metastasis, endowing them with the ability to function as evaluation, predictive, and therapeutic indicators. The article aims to synthesize the existing information concerning the functions of lncRNAs in ECs, elucidating their regulatory mechanisms and clinical significance. By delving into the lncRNAs' expanding relevance in the modulation of oncogenic and tumor-suppressive networks, we gain a deeper understanding of the molecular complexities intrinsic to these diseases. In our exploration of the genomic intricacies of ECs, lncRNAs introduce a fresh perspective, providing an opportunity to function as clinical and therapeutic indicators, and they also have therapeutic benefits that show promise for advancing the treatment of ECs. This comprehensive review bridges the intricate relationship between lncRNAs and ECs within the context of the genomic era.

SEMA3B-AS1 suppresses colorectal carcinoma progression by inhibiting Semaphorin 3B-dependent VEGF signaling pathway activation

Mounting evidence has demonstrated the considerable regulatory effects of long noncoding RNAs (lncRNAs) in the tumorigenesis and progression of various carcinomas. LncRNA Semaphorin 3B (SEMA3B) antisense RNA 1 (SEMA3B-AS1) has been found to be dysregulated in a few carcinomas recently. However, its potential function and mechanism in colorectal carcinoma (CRC) have not yet been examined. Here we show that SEMA3B-AS1 acts as a crucial regulator of CRC progression. We found that SEMA3B-AS1 expression was downregulated in CRC cell lines and tissues. Downregulation of SEMA3B-AS1 was significantly associated with poor survival in CRC patients. Overexpression of SEMA3B-AS1 reduced the cell growth and metastasis of CRC in vivo and in vitro. In addition, SEMA3B-AS1 promoted the expression of its sense-cognate gene SEMA3B, a member of the Semaphorin family (SEMAs), by recruiting EP300 to induce H3K9 acetylation at the SEMA3B promoter. Furthermore, we proved that SEMA3B-AS1 suppressed CRC angiogenesis by affecting the vascular endothelial growth factor signaling pathway activation which was regulated by the SEMA3B-NRP1 axis. Our work unravels a novel mechanism of SEMA3B-AS1 in the inhibition of CRC malignant progression and highlights its probability as a new promising diagnostic marker and therapeutic target for CRC interventions.

LINC01082 Inhibits Non-Small Cell Lung Cancer by Targeting the miR-543/TNRC6A Axis

Non-small cell lung cancer (NSCLC) accounts for over 80% of lung cancer cases and have poor clinical outcomes. Increasing number of lncRNAs are reported to be implicated in the carcinogenesis of NSCLC. Previous lncRNA-seq results showed that LINC01082 was under-expressed in several cancer types. In the current study, we focused on the role of LINC01082 in NSCLC development. An online bioinformatics tool was utilized to assess the expression profile of LINC01082, miR-543, and TNRC6A in NSCLC samples. RT-qPCR analysis was performed for evaluating LINC01082, TNRC6A and miR-543 expression in cells (NSCLC cells vs. normal lung cells). Impact of LINC01082 upregulation on cell proliferation in vitro was investigated by MTT and EdU experiments. Transwell assay was applied to analyze the migration and invasion of NSCLC cells. The cell apoptosis after plasmid transfection was detected by flow cytometry. The interactions among LINC01082, miR-543 and TNRC6A were measured by RNA pulldown and luciferase reporter assays. We showed that LINC01082 levels were downregulated in NSCLC samples and NSCLC cells. Overexpression of LINC01082 inhibited NSCLC cell proliferation, migration and invasion and strengthened cell apoptosis. LINC01082 directly bound to miR-543, and miR-543 targeted TNRC6A. TNRC6A was downregulated and miR-543 was overexpressed in NSCLC cells. miR-543 inhibition suppressed malignant cellular behaviors. TNRC6A knockdown reversed the effects of LINC01082 on the malignant character of NSCLC cells. In conclusion, LINC01082 exerts an antioncogenic role in NSCLC via interaction with miR-543 to regulate TNRC6A expression.

Mutual interaction of lncRNAs and epigenetics: focusing on cancer

Long noncoding RNAs are characterized as noncoding transcripts longer than 200 nucleotides in response to a variety of functions within the cells. They are involved in almost all cellular mechanisms so as epigenetics. Given that epigenetics is an important phenomenon, which participates in the biology of complex diseases, many valuable studies have been performed to demonstrate the control status of lncRNAs and epigenetics. DNA methylation and histone modifications as epigenetic mechanisms can regulate the expression of lncRNAs by affecting their coding genes. Reciprocally, the three-dimensional structure of lncRNAs could mechanistically control the activity of epigenetic-related enzymes. Dysregulation in the mutual interaction between epigenetics and lncRNAs is one of the hallmarks of cancer. These mechanisms are either directly or indirectly involved in various cancer properties such as proliferation, apoptosis, invasion, and metastasis. For instance, lncRNA HOTAIR plays a role in regulating the expression of many genes by interacting with epigenetic factors such as DNA methyltransferases and EZH2, and thus plays a role in the initiation and progression of various cancers. Conversely, the expression of this lncRNA is also controlled by epigenetic factors. Therefore, focusing on this reciprocated interaction can apply to cancer management and the identification of prognostic, diagnostic, and druggable targets. In the current review, we discuss the reciprocal relationship between lncRNAs and epigenetic mechanisms to promote or prevent cancer progression and find new potent biomarkers and targets for cancer diagnosis and therapy.

Long non-coding RNAs and melanoma: From diagnosis to therapy

Although extremely rare, malignant melanoma is the deadliest type of skin malignancy with the inherent capability to invade other organs and metastasize to distant tissues. In 2021, it was estimated that approximately 106,110 patients may have received the diagnosis of melanoma, with a mortality rate of 7180. Surgery remains the common choice for treatment in patients with melanoma. Despite many advances in the treatment of melanoma, some patients, such as those who have received cytotoxic chemotherapeutic and immunotherapic agents, a significant number of patients may show inadequate treatment response following initiating these treatments. Non-coding RNAs, including lncRNAs, have become recently popular and attracted the attention of many researchers to make new insights into the pathogenesis of many diseases, particularly malignancies. LncRNAs have been thoroughly investigated in multiple cancers such as melanoma and have been shown to play a major role in regulating various physiological and pathological cellular processes. Considering their core regulatory function, these non-coding RNAs may be appropriate candidates for melanoma patients' diagnosis, prognosis, and treatment. In this review, we will cover all the current literature available for lncRNAs in melanoma and will discuss their potential benefits as diagnostic and/or prognostic markers or potent therapeutic targets in the treatment of melanoma patients.

Metformin suppresses lung adenocarcinoma by downregulating long non-coding RNA (lncRNA) AFAP1-AS1 and secreted phosphoprotein 1 (SPP1) while upregulating miR-3163

AFAP1-AS1 plays a pro-tumor role in lung cancer. However, no investigation has focused on whether it is involved in the anticancer activity of metformin (Met) in the treatment of lung adenocarcinoma (LUAD). Reverse transcription quantitative polymerase chain reaction (RT-qPCR) was performed to detect the expression of long non-coding (lnc)RNA AFAP1-AS1, the microRNA (miR)-3163, and secreted phosphoprotein 1 (SPP1) in LUAD tissues, or of A549 and H3122 cells. Cell Counting Kit-8, wound scratch, and cell invasion assays were performed to evaluate the effect of the overexpression of lncRNA AFAP1-AS1, miR-3163, and SPP1 on the malignant behaviors of A549 and H3122 cells. Phosphatidylinositol 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/Akt/mTOR) signaling pathway-related proteins were detected by Western blot analysis. Dual luciferase reporter or RIP assays were used to determine the interplay between AFAP1-AS1 and miR-3163, or of miR-3163 and SPP1. Met inhibits the malignant characteristics of A549 and H3122 cells in vitro. GEPIA database analysis showed that AFAP1-AS1 is a highly expressed lncRNA in LUAD tissues, which was validated by RT-qPCR. Overexpression of AFAP1-AS1 suppressed the met-mediated anti-tumor activity in A549 and H3122 cells, while AFAP1-AS1 silencing promoted it. Met inhibited AFAP1-AS1 expression, which resulted in reduced proliferation, migration, and invasion in A549 and H3122 cells. This led to AFAP1-AS1-mediated suppression of miR-3163 and, subsequently, the upregulation of SPP1. Met exerts its antitumor activities by regulating the AFAP1-AS1/miR-3163/SPP1/PI3K/Akt/mTOR axis. Our findings deepen our understanding of mechanisms underlying anti-tumor effect of Met in LUAD.

A Signature of 14 Long Non-Coding RNAs (lncRNAs) as a Step towards Precision Diagnosis for NSCLC

LncRNAs have arisen as new players in the world of non-coding RNA. Disrupted expression of these molecules can be tightly linked to the onset, promotion and progression of cancer. The present study estimated the usefulness of 14 lncRNAs (HAGLR, ADAMTS9-AS2, LINC00261, MCM3AP-AS1, TP53TG1, C14orf132, LINC00968, LINC00312, TP73-AS1, LOC344887, LINC00673, SOX2-OT, AFAP1-AS1, LOC730101) for early detection of non-small-cell lung cancer (NSCLC). The total RNA was isolated from paired fresh-frozen cancerous and noncancerous lung tissue from 92 NSCLC patients diagnosed with either adenocarcinoma (LUAD) or lung squamous cell carcinoma (LUSC). The expression level of lncRNAs was evaluated by a quantitative real-time PCR (qPCR). Based on Ct and delta Ct values, logistic regression and gradient boosting decision tree classifiers were built. The latter is a novel, advanced machine learning algorithm with great potential in medical science. The established predictive models showed that a set of 14 lncRNAs accurately discriminates cancerous from noncancerous lung tissues (AUC value of 0.98 ± 0.01) and NSCLC subtypes (AUC value of 0.84 ± 0.09), although the expression of a few molecules was statistically insignificant (SOX2-OT, AFAP1-AS1 and LOC730101 for tumor vs. normal tissue; and TP53TG1, C14orf132, LINC00968 and LOC730101 for LUAD vs. LUSC). However for subtypes discrimination, the simplified logistic regression model based on the four variables (delta Ct AFAP1-AS1, Ct SOX2-OT, Ct LINC00261, and delta Ct LINC00673) had even stronger diagnostic potential than the original one (AUC value of 0.88 ± 0.07). Our results demonstrate that the 14 lncRNA signature can be an auxiliary tool to endorse and complement the histological diagnosis of non-small-cell lung cancer.

A Review on the Role of AFAP1-AS1 in the Pathoetiology of Cancer

AFAP1-AS1 is a long non-coding RNA which partakes in the pathoetiology of several cancers. The sense protein coding gene from this locus partakes in the regulation of cytophagy, cell motility, invasive characteristics of cells and metastatic ability. In addition to acting in concert with AFAP1, AFAP1-AS1 can sequester a number of cancer-related miRNAs, thus affecting activity of signaling pathways involved in cancer progression. Most of animal studies have confirmed that AFAP1-AS1 silencing can reduce tumor volume and invasive behavior of tumor cells in the xenograft models. Moreover, statistical analyses in the human subjects have shown strong correlation between expression levels of this lncRNA and clinical outcomes. In the present work, we review the impact of AFAP1-AS1 in the carcinogenesis.

Silencing of LncRNA AFAP1-AS1 Inhibits Cell Proliferation in Oral Squamous Cancer by Suppressing CCNA2

Background

Evidence has indicated that dysregulation of long noncoding RNAs (lncRNA) is a critical factor in the occurrence of many diseases, including cancer. The lncRNA AFAP1-AS1 has been shown to participate in oncogenesis, metastasis, or drug resistance in many types of cancer. However, the potential role of AFAP1-AS1 in oral squamous cell carcinoma (OSCC) has not been fully elucidated.

Methods

Bioinformatics analysis was performed to compare AFAP1-AS1 expression levels in OSCC cancer samples and in normal controls. The biological function of AFAP1-AS1 was studied through loss-of-function assays. To study the potential mechanisms, high-throughput sequencing was applied to OSCC cancer samples and a series of bioinformatics analyses were performed. The effects of AFAP1-AS1 on OSCC tumor growth was evaluated by in vivo xenograft tumor formation assays.

Results

Bioinformatics analyses indicated that AFAP1-AS1 was upregulated in OSCC. Overexpression of AFAP1-AS1 was positively correlated with lymph node metastasis, tumor stage, and pathological grade. Down-regulation of AFAP1-AS1 in OSCC led to decreased proliferation in vitro and, notably, inhibition of tumor growth in vivo. Further research indicated that AFAP1-AS1 regulated OSCC cell proliferation by targeting CCNA2.

Conclusion

AFAP1-AS1 promotes tumor proliferation and indicates a poor prognosis in OSCC, providing a potential therapeutic strategy.

The regulatory role of antisense lncRNAs in cancer

Antisense long non-coding RNAs (antisense lncRNAs), transcribed from the opposite strand of genes with either protein coding or non-coding function, were reported recently to play a crucial role in the process of tumor onset and development. Functionally, antisense lncRNAs either promote or suppress cancer cell proliferation, migration, invasion, and chemoradiosensitivity. Mechanistically, they exert their regulatory functions through epigenetic, transcriptional, post-transcriptional, and translational modulations. Simultaneously, because of nucleotide sequence complementarity, antisense lncRNAs have a special role on its corresponding sense gene. We highlight the functions and molecular mechanisms of antisense lncRNAs in cancer tumorigenesis and progression. We also discuss the potential of antisense lncRNAs to become cancer diagnostic biomarkers and targets for tumor treatment.

Keep your eyes peeled for long noncoding RNAs: Explaining their boundless role in cancer metastasis, drug resistance, and clinical application

Cancer metastasis and drug resistance are two major obstacles in the treatment of cancer and therefore, the leading cause of cancer-associated mortalities worldwide. Hence, an in-depth understanding of these processes and identification of the underlying key players could help design a better therapeutic regimen to treat cancer. Earlier thought to be merely transcriptional junk and having passive or secondary function, recent advances in the genomic research have unravelled that long noncoding RNAs (lncRNAs) play pivotal roles in diverse physiological as well as pathological processes including cancer metastasis and drug resistance. LncRNAs can regulate various steps of the complex metastatic cascade such as epithelial-mesenchymal transition (EMT), invasion, migration and metastatic colonization, and also affect the sensitivity of cancer cells to various chemotherapeutic drugs. A substantial body of literature for more than a decade of research evince that lncRNAs can regulate gene expression at different levels such as epigenetic, transcriptional, posttranscriptional, translational and posttranslational levels, depending on their subcellular localization and through their ability to interact with DNA, RNA and proteins. In this review, we mainly focus on how lncRNAs affect cancer metastasis by modulating expression of key metastasis-associated genes at various levels of gene regulation. We also discuss how lncRNAs confer cancer cells either sensitivity or resistance to various chemo-therapeutic drugs via different mechanisms. Finally, we highlight the immense potential of lncRNAs as prognostic and diagnostic biomarkers as well as therapeutic targets in cancer.

lncRNA OXCT1-AS1 Promotes Metastasis in Non-Small-Cell Lung Cancer by Stabilizing LEF1, In Vitro and In Vivo

Long noncoding RNAs (lncRNAs) play nonnegligible roles in the metastasis of non-small-cell lung cancer (NSCLC). This study is aimed at investigating the biological role of lncRNA OXCT1-AS1 in NSCLC metastasis and the underlying regulatory mechanisms. The expression profiles of lncRNA OXCT1-AS1 in different NSCLC cell lines were examined. Then, the biological function of lncRNA OXCT1-AS1 in NSCLC metastasis was explored by loss-of-function assays in vitro and in vivo. Further, the protective effect of lncRNA OXCT1-AS1 on lymphoid enhancer factor 1 (LEF1) was examined using RNA pull-down and RNA immunoprecipitation assays. Additionally, the role of LEF1 in NSCLC metastasis was investigated. Results indicated that lncRNA OXCT1-AS1 expression was significantly increased in NSCLC cell lines. Functional analysis revealed that knockdown of lncRNA OXCT1-AS1 impaired invasion and migration in vitro. Additionally, the ability of lncRNA OXCT1-AS1 to promote NSCLC metastasis was also confirmed in vivo. Mechanistically, through direct interaction, lncRNA OXCT1-AS1 maintained LEF1 stability by blocking NARF-mediated ubiquitination. Furthermore, LEF1 knockdown impaired invasion and migration of NSCLC in vitro and in vivo. Collectively, these data highlight the ability of lncRNA OXCT1-AS1 to promote NSCLC metastasis by stabilizing LEF1 and suggest that lncRNA OXCT1-AS1 represents a novel therapeutic target in NSCLC.

AFAP1-AS1: a rising star among oncogenic long non-coding RNAs

Long non-coding RNAs (lncRNAs) have become a hotspot in biomedical research. This interest reflects their extensive involvement in the regulation of the expression of other genes, and their influence on the occurrence and development of a variety of human diseases. Actin filament associated protein 1-Antisense RNA 1(AFAP1-AS1) is a recently discovered oncogenic lncRNA. It is highly expressed in a variety of solid tumors, and regulates the expression of downstream genes and signaling pathways through adsorption and competing microRNAs, or by the direct binding to other proteins. Ultimately, AFAP1-AS1 promotes proliferation, chemotherapy resistance, and resistance to apoptosis, maintains stemness, and enhances invasion and migration of tumor cells. This paper summarizes the research concerning AFAP1-AS1 in malignant tumors, including the clinical application prospects of AFAP1-AS1 as a potential molecular marker and therapeutic target of malignant tumors. We also discuss the limitations in the knowledge of AFAP1-AS1 and directions of further research. AFAP1-AS1 is expected to provide an example for studies of other lncRNA molecules.

Mechanism underlying the stimulation by IGF-1 of LHCGR expression in porcine granulosa cells

IGF-1 plays important roles in mammalian fertility by promoting cell growth and increasing steroid hormone secretion. Although IGF-1 significantly upregulated luteinizing hormone/choriogonadotropin receptor (LHCGR) gene expression in granulosa cells in a previous study, the mechanism was unclear. The present experiment was designed to primarily explore the regulation of LHCGR expression by IGF-1. First, based on a porcine LHCGR double-luciferase reporter experiment, c-Fos significantly inhibited the activity of the LHCGR promoter. Second, porcine granulosa cells were cultured in vitro with IGF-1, and we observed that the expression of LHCGR was significantly increased and the expression of c-Fos mRNA significantly reduced. After c-Fos overexpression in granulosa cells, IGF-1 attenuated the inhibitory effect of c-Fos on LHCGR. Furthermore, the level of LHCGR mRNA stimulated by IGF-1 in the presence of SB203580 was markedly lower than that of IGF-1 alone action. In conclusion, IGF-1 enhanced the expression of LHCGR by regulating c-Fos in granulosa cells, which may be mediated by the p38MAPK-signaling pathway.

Aberrant methylation modifications reflect specific drug responses in small cell lung cancer

In the study, Methylated DNA immunoprecipitation sequencing, RNA sequencing, and whole-exome sequencing were employed to clinical small cell lung cancer (SCLC) patients. Then, we verified the therapeutic predictive effects of differentially methylated genes (DMGs) in 62 SCLC cell lines. Of 4552 DMGs between chemo-sensitive and chemo-insensitive group, coding genes constituted the largest percentage (85.08%), followed by lncRNAs (10.52%) and miRNAs (3.56%). Both two groups demonstrated two methylation peaks near transcription start site and transcription end site. Two lncRNA-miRNA-mRNA networks suggested the extensive genome connection between chemotherapy efficacy-related non-coding RNAs (ncRNAs) and mRNAs. Combing miRNAs and lncRNAs could effectively predict chemotherapy response in SCLC. In addition, we also verified the predictive values of mutated genes in SCLC cell lines. This study was the first to evaluate multiple drugs efficacy-related ncRNAs and mRNAs which were modified by methylation in SCLC. DMGs identified in our research might serve as promising therapeutic targets to reverse drugs-insensitivity by complex lncRNA-miRNA-mRNA mechanisms in SCLC.

The long non-coding RNA SNHG4/microRNA-let-7e/KDM3A/p21 pathway is involved in the development of non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is a foremost cause of malignancy-associated mortality globally. Recent studies have emphasized long non-coding RNAs (lncRNAs) as important biomarkers with diagnostic and therapeutic potential in regard to NSCLC. This study aimed to elucidate the functional role of lncRNA small nucleolar RNA host gene 4 (SNHG4) in NSCLC. Initially, 50 paired cancerous and noncancerous tissues were obtained from NSCLC patients. Human NSCLC H1299 cells were assayed to evaluate viability, colony formation, invasion, migration, cycle arrest, and apoptosis via Cell Counting Kit-8 (CCK-8), plate clone formation, and transwell invasion assays, as well as a scratch test and flow cytometry. A dual-luciferase reporter gene assay was used to examine lncRNA SNHG4 binding with miR-let-7e and miR-let-7e binding with lysine demethylase 3A (KDM3A). H1299 cells were xenografted into nude mice. lncRNAs SNHG4 and KDM3A were both upregulated in NSCLC tissues. The knockdown of lncRNA SNHG4 or KDM3A inhibited H1299 cell viability, colony formation, invasion, migration, and cycle progression while inducing apoptosis. lncRNA SNHG4 was found to bind to miR-let-7e that negatively targeted KDM3A. KDM3A inhibited p53-K372me1, thus reducing p21 expression. The NSCLC development was inhibited by downregulating lncRNA SNHG4 in nude mice. Taken together, the key findings of the current study demonstrate a novel lncRNA SNHG4/let-7e/KDM3A/p21 axis in NSCLC, highlighting a promising therapeutic target for NSCLC.

A four-methylated LncRNA signature predicts survival of osteosarcoma patients based on machine learning

Risk stratification using prognostic markers facilitates clinical decision-making in treatment of osteosarcoma (OS). In this study, we performed a comprehensive analysis of DNA methylation and transcriptome data from OS patients to establish an optimal methylated lncRNA signature for determining OS patient prognosis. The original OS datasets were downloaded from the the Therapeutically Applicable Research to Generate Effective Treatments (TARGET) database. Univariate, Lasso, and machine learning algorithm-iterative Lasso Cox regression analyses were used to establish a methylated lncRNA signature that significantly correlated with OS patient survival. The validity of this signature was verified by the Kaplan-Meier curves, Receiver Operating Characteristic (ROC) curves. We established a four-methylated lncRNA signature that can predict OS patient survival (verified in independent cohort [GSE39055]). Kaplan-Meier analysis showed that the signature can distinguish between the survival of high- and low-risk patients. ROC analysis corroborated this finding and revealed that the signature had higher prediction accuracy than known biomarkers. Kaplan-Meier analysis of the clinical subgroup showed that the signature's prognostic ability was independent of clinicopathological factors. The four-methylated lncRNA signature is an independent prognostic biomarker of OS.

New insights into long non-coding RNAs in non-small cell lung cancer

Lung cancer is a malignant tumor that seriously threatens human life and health. Non-small cell lung cancer (NSCLC) accounts for 85 % of all lung cancer cases, and its global 5-year survival rate is only approximately 5%. Thus, the identification of new prognostic biomarkers has become one of the most urgent challenges in NSCLC research. Long noncoding RNAs (LncRNAs) are a kind of noncoding RNA whose length exceeds 200 nucleotides (nt). LncRNAs are transcribed by RNA pol II and can be subjected to posttranscriptional modifications such as blocking, polyadenylation and splicing; moreover, their expression profiles are more specific than those of mRNAs. Emerging evidence confirms that lncRNAs are associated with the occurrence and development of NSCLC and play an important role in NSCLC drug resistance. The purpose of this review was to describe the roles of lncRNAs in the development, diagnosis and prognosis of NSCLC and to explore new evidence of lncRNAs in the treatment of NSCLC drug resistance. This review provides a new perspective of lncRNAs in the treatment of NSCLC.

Aberrant methylation-mediated downregulation of lncRNA CCND2 AS1 promotes cell proliferation in cervical cancer

Background

Long non-coding RNA (lncRNA) plays an important role in tumorigenesis. The lncRNA CCND2 AS1 has been shown to be involved in the growth of several tumors; however, its role in cervical cancer has not been elucidated. This study aimed to explore the expression, function, and underlying mechanism of action of CCND2 AS1 in cervical cancer. Expression of CCND2 AS1 was examined in cervical cancer and adjacent normal cervical tissues by quantitative real-time polymerase chain reaction (qRT-PCR) and by bioinformatic analysis of data from the Gene Expression Profiling Interactive Analysis (GEPIA) database. The function of CCND2 AS1 was investigated by overexpressing or silencing CCND2 AS1 in HeLa and SiHa cervical cancer cells followed by in vitro and in vivo analyses. Methylation-specific PCR (MSP) and bisulfite genomic sequencing (BGS) were used to detect CCND2 AS1 promoter methylation status in cervical cancer cells.

Results

CCND2 AS1 expression was lower in cervical cancer compared with normal cervical tissues, and the level was significantly correlated with the patient age and tumor size. CCND2 AS1 overexpression inhibited the proliferation and cell cycle progression of HeLa cells in vitro and/or in vivo, whereas CCND2 AS1 silencing had the opposite effects. CCND2 AS1 expression was elevated after treatment of cervical cancer cells with the DNA methyltransferase inhibitor 5′-azacytidine (5′-Aza), and this was mediated, at least in part, via reduced CpG methylation at the CCND2 AS1 promoter.

Conclusion

CCND2 AS1 expression is downregulated in cervical cancer, potentially through increased CCND2 AS1 promoter methylation, and the upregulation of CCND2 AS1 expression inhibited tumor growth. These data suggest that CCND2 AS1 could be a diagnostic marker and potential therapeutic target for cervical cancer.

SNHG11 contributes to NSCLC cell growth and migration by targeting miR-485-5p/BSG axis

Accumulating studies implied that long noncoding RNAs (lncRNAs) act as essential factors in regulating diverse biological behaviors of cancers. Small nucleolar RNA host gene 11 (SNHG11) has been reported as for its oncogenic properties in several cancer types. However, it is unclear whether SNHG11 exerts functions in non-small cell lung cancer (NSCLC) remains unclear. The aim of this study was to inspect the role and regulatory mechanism of SNHG11 in NSCLC. The expression of SNHG11 in NSCLC cells was analyzed by qRT-PCR. Functional experiments were carried out to determine the effects of SNHG11 silence on the biological behaviors of NSCLC cells, including growth, migration and epithelial-mesenchymal transition. The inhibition of above functions was observed after SNHG11 was silenced. Subcellular fractionation and FISH assays were performed to detect the cellular distribution of SNHG11. Moreover, SNHG11 was found to be a sponge of miR-485-5p that could directly target to Basigin (BSG) mRNA. The interaction between SNHG11 and miR-485-5p as well as between miR-485-5p and BSG was proven by RNA pull down and luciferase reporter assays. Restoration assay confirmed the involvement of miR-485-5p and BSG in SNHG11-mediated NSCLC cellular functions. Conclusively, SNHG11 was overexpressed in NSCLC and functioned as a miR-485-5p sponge to up-regulate BSG.

Expression of long non-coding RNA SFTA1P and its function in non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is a major type of lung cancer with high morbidity and mortality. Long non-coding RNAs (lncRNAs) have been reported to be important in development and progression of NSCLC. However, the role of lncRNA SFTA1P remains unclear. This study aims to explore the clinical roles, biological function, and mechanism of SFTA1P in NSCLC. SFTA1P expression was estimated by the quantitative real-time polymerase chain reaction (qRT-PCR) of 90 pairs of tissue samples, the Cancer Genome Atlas (TCGA) database and microarray. After overexpressing SFTA1P, NSCLC cell proliferation, cycle, and apoptosis were detected. We found that the expression of SFTA1P was significantly downregulated in NSCLC tissues with high diagnostic value (AUC = 0.87), which was consistent with the results of TCGA and microarray data. For the analysis of clinical features, the results revealed that SFTA1P expression was closely related to the pathological type (P < 0.01). Furthermore, the cell function results suggested that the overexpression of SFTA1P triggered cell cycle arrest in the S-phase (P < 0.05). From a mechanistic perspective, the results showed that the PI3K-AKT signaling pathway was inhibited after overexpression of SFTA1P in NSCLC. Taken together, this work supported that SFTA1P may play a suppressing role in the tumorigenesis of NSCLC by modulating PI3K-AKT signaling pathway to influence cell cycle, which provides a potential and prospective biomarker for NSCLC.

DGUOK-AS1 promotes cell proliferation in cervical cancer via acting as a ceRNA of miR-653-5p

Cervical cancer (CC) holds the second highest incidence and is the fourth dominating cause of cancer-induced death in women. It has been widely accepted that long noncoding RNAs (lncRNAs) are implicated in pathological and physiological activities of CC. However, the research of lncRNAs is still in the initial stage. The biological function of lncRNA deoxyguanosine kinase antisense RNA 1 (DGUOK-AS1) in human cancers has not been reported yet. We found that DGUOK-AS1 was aberrantly upregulated in cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) tissues through TCGA database. Real-time quantitative polymerase chain reaction (RT-qPCR) also verified the high expression of DGUOK-AS1 in CC cell lines. Loss-of-function assays indicated that DGUOK-AS1 silence repressed CC cell growth. In addition, dual-luciferase reporter and RNA immunoprecipitation (RIP) experiments validated the binding relation between miR-653-5p and DGUOK-AS1 or EMSY. Results of the rescue assays elucidated that EMSY overexpression or miR-653-5p downregulation reversed the suppressive function of DGUOK-AS1 knockdown on cell growth and DNA repair in CC. To sum up, this research highlighted that DGUOK-AS1 could promote CC cell proliferation via serving as a ceRNA of miR-653-5p to release EMSY, which might inspire us to discover novel strategies for CC treatment. SIGNIFICANCE OF THE STUDY: DGUOK-AS1 knockdown hinders proliferation of CC cells. DGUOK-AS1 sequesters miR-653-5p to elevate EMSY in CC. EMSY is required for DGUOK-AS1 to induce cell proliferation and repress DNA damage in CC.

Exosome-transmitted lncRNA UFC1 promotes non-small-cell lung cancer progression by EZH2-mediated epigenetic silencing of PTEN expression

Long non-coding RNAs (LncRNAs) have been suggested as important regulators of cancer development and progression in non-small cell lung cancer (NSCLC). Nevertheless, the biological roles and clinical significance of lncRNA UFC1 in NSCLC remain unclear. We detected the expression of UFC1 in tumor tissues, serum, and serum exosomes of NSCLC patients by qRT-PCR. Gene overexpression or silencing were used to examine the biological roles of UFC1 in NSCLC. RNA immunoprecipitation and ChIP assays were performed to evaluate the interaction between UFC1 and enhancer of zeste homolog 2 (EZH2) and the binding of EZH2 to PTEN gene promoter. Rescue study was used to access the importance of PTEN regulation by UFC1 in NSCLC progression. UFC1 expression was upregulated in tumor tissues, serum, and serum exosomes of NSCLC patients and high level of UFC1 was associated with tumor infiltration. UFC1 knockdown inhibited NSCLC cell proliferation, migration and invasion while promoted cell cycle arrest and apoptosis. UFC1 overexpression led to the opposite effects. Mechanistically, UFC1 bound to EZH2 and mediated its accumulation at the promoter region of PTEN gene, resulting in the trimethylation of H3K27 and the inhibition of PTEN expression. UFC1 knockdown inhibited NSCLC growth in mouse xenograft tumor models while the simultaneous depletion of PTEN reversed this effect. NSCLC cells derived exosomes could promote NSCLC cell proliferation, migration and invasion through the transfer of UFC1. Moreover, Exosome-transmitted UFC1 promotes NSCLC progression by inhibiting PTEN expression via EZH2-mediated epigenetic silencing. Exosome-mediated transmit of UFC1 may represent a new mechanism for NSCLC progression and provide a potential marker for NSCLC diagnosis.

Long non-coding RNA AFAP1-AS1 accelerates the progression of melanoma by targeting miR-653-5p/RAI14 axis

BACKGROUND

Melanoma is the most aggressive skin cancer that derived from pigment cells, accounting for the majority of the skin-cancer-related deaths. Despite great development and evolution have been made in surgery, radiotherapy and adjuvant chemotherapy, the prognosis of melanoma patients exhibited no significant improvement. Long noncoding RNAs (lncRNAs) are frequently dysregulated and involved in the development of cancers. LncRNA AFAP1-AS1 has been explored in various cancers, whereas its role and regulatory mechanism in melanoma are not well understood.

METHODS

The expression of AFAP1-AS1 was detected by qRT-PCR. CCK-8, colony formation, transwell and western blot assays were performed to investigate the biological role of AFAP1-AS1 in melanoma. Male BALB/c nude mice were applied for in vivo experiments. The interaction among AFAP1-AS1, miR-653-5p and RAI14 was investigated by RNA pull down, RIP and luciferase reporter assays.

RESULTS

AFAP1-AS1 was highly expressed in melanoma cell lines. Suppression of AFAP1-AS1 impaired cell proliferation, migration, invasion and EMT in melanoma. Moreover, AFAP1-AS1 was a ceRNA of RAI14 by competitively binding with miR-653-5p. Besides, miR-653-5p overexpression or RAI14 inhibition could repress tumor growth. Eventually, rescue assays indicated that the function of AFAP1-AS1 in the cellular process of melanoma was dependent on miR-653-5p and RAI14.

CONCLUSIONS

AFAP1-AS1 exerts its oncogenic function in melanoma by targeting miR-653-5p/RAI14 axis.

Bidirectional interaction of lncRNA AFAP1-AS1 and CRKL accelerates the proliferative and metastatic abilities of hepatocarcinoma cells

Actin filament-associated protein 1 antisense RNA 1 (AFAP1-AS1), a long non-coding RNA transcribed from the antisense strand of protein coding gene AFAP1, has attracted attention in cancer research. Despite, its biological function and regulatory mechanism in hepatocellular carcinoma still unknown. The present study revealed AFAP1-AS1 mediated hepatocarcinoma progression through targeting CRKL. The bidirectional interaction of AFAP1-AS1 and oncogenic protein CRKL, and the deregulation of AFAP1-AS1 effects on Ras, MEK and c-Jun activities were investigated in depth. AFAP1-AS1 was upregulated in surgical tumorous tissues from hepatocarcinoma patients compared with the paired paracancerous non-tumor liver tissues, and in hepatocarcinoma Huh7, HCCLM3 and HepG2 cell lines compared with LO2, a normal liver cell line. AFAP1-AS1 knockdown noticeably suppressed the proliferative, migratory and invasive properties, and the epithelial-mesenchymal transition (EMT) process of HepG2 and HCCLM3 through upregulating E-cadherin and downregulating N-cadherin and vimentin. CRKL knockdown reduced AFAP1-AS1 expression levels in HepG2 and HCCLM3 cells. AFAP1-AS1 suppression impaired CRKL expression in HepG2 and HCCLM3. AFAP1-AS1 level change was positively correlated with the expression level changes of Ras, MEK and c-Jun in mediating the invasiveness of hepatocarcinoma cells. Current work demonstrated AFAP1-AS1 to be an applicable progression indicator of hepatocarcinoma. AFAP1-AS1 probably promotes the proliferation, EMT progression and metastasis of hepatocarcinoma cells via CRKL mediated Ras/MEK/c-Jun and cadherin/vimentin signaling pathways. AFAP1-AS1-CRKL bidirectional feedback signaling is worthy of further study on the monitoring, diagnosis and treatment of cancers.

LncRNA MACC1-AS1 Promotes Lung Adenocarcinoma Cell Proliferation by Downregulating PTEN

Background: MACC1-AS1 is an oncogenic lncRNA in gastric cancer, which interacts with AMP-activated protein kinase (AMPK) to promote cancer development. AMPK is known to interact with phosphatase and tensin homolog (PTEN). Therefore, MACC1-AS1 may also have associations with PTEN. This study aimed to investigate the interactions between MACC1-AS1 and PTEN in lung adenocarcinoma (LUAD). Materials and Methods: This study recruited 64 LUAD patients admitted to The First People's Hospital of Wenling City. Gene and protein expression levels were determined by qPCR and western blot, respectively. Cell transfections were performed to assess gene interactions. Cell proliferation was evaluated by CCK-8 assay. Results: MACC1-AS1 was upregulated in LUAD and inversely correlated with the expression of PTEN. High expression levels of MACC1-AS1 in LUAD tissues were closely correlated with poor survival rate of LUAD patients. In LUAD cells, overexpression of MACC1-AS1 led to decreased expression of PTEN and increased proliferation rate of LUAD cells, while MACC1-AS1 silencing led to increased expression of PTEN and decreased proliferation rate of LUAD cells. Furthermore, overexpression of PTEN attenuated the effects of overexpressing MACC1-AS1. Conclusions: The authors' results demonstrated that MACC1-AS1 promoted cell proliferation by downregulating PTEN in LUAD cells.

LncRNA HOTAIR targets miR-126-5p to promote the progression of Parkinson's disease through RAB3IP

Parkinson's disease (PD) is a common neurological disorder characterized by dopaminergic (DA) neuron degeneration and death in the midbrain, and the long noncoding RNA HOTAIR has been shown to affect disease progression in PD. In this study, we aimed to further illustrate the molecular mechanism of HOTAIR in PD. Bioinformatics analysis was utilized to determine the potential downstream targets of HOTAIR in PD. Luciferase assay and the RNA Binding Protein Immunoprecipitation (RIP) assay were used to validate the existence of binding sites between competing endogenous RNAs (ceRNAs). Real-time quantitative polymerase chain reaction (qRT-PCR) and Western blotting indicated that HOTAIR and RAB3IP increased while miR-126-5p decreased in PD cells and PD mice. Additionally, the CCK-8 assay and flow cytometric analysis indicated that the knockdown of HOTAIR and RAB3IP and the overexpression of miR-126-5p significantly increased cell proliferation and reduced apoptosis in PD cells. Furthermore, the results of in vivo experiments suggested that knockdown of HOTAIR expression increased the number of TH-positive cells and the number of α-synuclein-positive cells decreased while reducing the apoptosis rate among DA neurons. Our study confirmed that HOTAIR promotes PD progression by regulating miR-126-5p and RAB3IP in a ceRNA-dependent manner and further clarified how HOTAIR works in PD.

Long Noncoding RNA AFAP1-AS1 Promotes Cell Proliferation and Metastasis via the miR-155-5p/FGF7 Axis and Predicts Poor Prognosis in Gastric Cancer

BACKGROUND

Actin filament-associated protein 1-antisense RNA 1 (AFAP1-AS1) plays an important role in the development and progression of several human cancers. However, its biological function in gastric cancer (GC) progression is still unknown.

METHODS

We used qRT-PCR to detect the relative expression of AFAP1-AS1 in GC tissues and cell lines. The loss-of-function assays were conducted to detect the effect of AFAP1-AS1 on GC development. Bioinformatics analysis, luciferase reporter gene analysis, and RIP analysis were used to identify and validate target genes of AFAP1-AS1. Finally, rescue tests were performed to confirm the influence of the AFAP1-AS1-miR-155-5p-FGF7 axis on GC development.

RESULTS

AFAP1-AS1 was upregulated in GC tissues and cell lines and was closely correlated with poor prognosis of GC patients. AFAP1-AS1 knockdown inhibited proliferation, migration, and invasion of GC cells, indicating that AFAP1-AS1 acts as an oncogene in GC. Bioinformatics analysis, dual-luciferase reporter gene detection, and RIP assays validated that AFAP1-AS1 directly interacts to miR-155-5p and could positively affect cell proliferation, migration, and invasion by regulation of the expression of miR-155-5p and FGF7. Further rescue assays revealed that AFAP1-AS1 promotes cell proliferation and metastasis through the miR-155-5p/FGF7 axis in GC.

CONCLUSIONS

AFAP1-AS1 might be an oncogenic lncRNA that promoted GC progression by acting as a competing endogenous RNA (ceRNA) that regulates the expression of FGF7 through sponging miR-155-5p, suggesting that AFAP1-AS1 may be a novel potential therapeutic target for GC.

Identification of lncRNA biomarkers in lung squamous cell carcinoma using comprehensive analysis of lncRNA mediated ceRNA network

Long non-coding RNAs (lncRNAs) act as a member of competing endogenous RNAs (ceRNAs) and plays a significant role in tumorigenesis. The aim of this study was to identify potential lncRNA biomarkers for predicting the prognosis of lung squamous cell carcinoma (LUSC) using a comprehensive analysis of lncRNA mediated ceRNA network. Differentially expressed RNAs datasets were obtained using edge R package in 502 LUSC tissues and 49 adjacent non-LUSC tissues from the Cancer Genome Atlas (TCGA). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed to identify functional enrichment implication of lncRNA related differentially expressed mRNAs. Survival analysis was used Kaplan-Meier curve method. Univariate and multivariate Cox regression analysis were performed to construct a predictive model with lncRNA biomarkers. A total of 2185 lncRNAs, 170 miRNAs and 2053 mRNAs were differentially expressed between LUSC tissues and adjacent non-LUSC tissues. The novel constructed ceRNA network incorporated 184 LUSC-specific lncRNAs, 18 miRNAs, and 49 mRNAs. About 11 of 184 differentially expressed lncRNAs and 1 of 18 differentially expressed miRNAs and 5 of 49 differentially expressed mRNAs were conspicuously related to overall survival (p < .05). Univariate and multivariate cox regression analysis showed that 6 lncRNAs were retrieved to construct a predictive model to predict the overall survival in LUSC patients. In conclusion, CeRNAs contributed to the progression of LUSC and a model with 6 lncRNAs might be potential biomarker for predicting the prognosis of LUSC.

Long Noncoding RNA GATA3-AS1 Promotes Cell Proliferation and Metastasis in Hepatocellular Carcinoma by Suppression of PTEN, CDKN1A, and TP53

BACKGROUND

Long noncoding RNAs (lncRNAs) have been known to play important roles in the progression of various types of human cancer. LncRNA GATA3 antisense RNA 1, GATA3-AS1, has been reported to be associated with T-cell development and differentiation. However, the expression pattern and function of GATA3-AS1 in hepatocellular carcinoma (HCC) remain unknown.

METHODS

Real-time quantitative PCR (RT-qPCR) assay was conducted to detect GATA3-AS1 expression levels in 80 cases of pairs HCC tissues and matched normal tissues. Chi-squared (χ ²) test was used to analyze the correlation between GATA3-AS1 expression and clinicopathologic variables. Survival curves were plotted using the Kaplan-Meier method and were compared via the log-rank test. The cell counting kit-8 (CCK-8) and wound scratch assays were applied to detect the effect of GATA3-AS1 knockdown and overexpression on cell growth and migration of HCC. RT-qPCR was performed for the detection of the phosphatase and tensin homolog (PTEN), cyclin-dependent kinase inhibitor 1A (CDKN1A), and tumor protein p53 (TP53) expression in HCC cells after GATA3-AS1 knockdown and overexpression.

RESULTS

GATA3-AS1 was significantly upregulated in HCC tissues compared with matched normal tissues. The high expression of GATA3-AS1 was significantly correlated with larger tumor size, advanced TNM stage, and more lymph node metastasis. High GATA3-AS1 expression was markedly correlated with shorter overall survival times of HCC patients. Furthermore, knockdown of GATA3-AS1 obviously inhibited Hep3B and HCCLM3 cell growth and migration, whereas overexpression of GATA3-AS1 had the opposite effects. In addition, GATA3-AS1 knockdown resulted in upregulated expression levels of tumor-suppressive genes, PTEN, CDKN1A, and TP53, in Hep3B and HCCLM3 cells, while restoration of GATA3-AS1 decreased PTEN, CDKN1A, and TP53 expression levels.

CONCLUSION

Our data suggested that GATA3-AS1 promotes cell proliferation and metastasis of HCC by suppression of PTEN, CDKN1A, and TP53.

Methylation and transcriptome analysis reveal lung adenocarcinoma-specific diagnostic biomarkers

Background

DNA methylation can regulate the role of long noncoding RNAs (lncRNAs) in the development of lung adenocarcinoma (LUAD). The present study aimed to identify methylation-driven lncRNAs and mRNAs as biomarkers in the prognosis of LUAD using bioinformatics analysis.

Methods

Differentially expressed RNAs were obtained using the edge R package from 535 LUAD tissues and 59 adjacent non-LUAD tissues. Differentially methylated genes were obtained using the limma R package from 475 LUAD tissues and 32 adjacent non-LUAD tissues. Methylation-driven mRNA and lncRNA were obtained using the MethylMix R package from 465 LUAD tissues with matched DNA methylation and RNA expression and 32 non-LUAD tissues with DNA methylation. Gene ontology and ConsensusPathDB pathway analysis were performed to identify functional enrichment of methylation-driven mRNAs. Univariate and multivariate Cox regression analyses were performed to identify the independent effect of each variable for predicting the prognosis of LUAD. Kaplan–Meier curve analysis of DNA methylation and gene expression might provide potential prognostic biomarkers for LUAD patients.

Results

A total of 99 methylation-driven mRNAs and 17 methylation-driven lncRNAs were obtained. Univariate and multivariate Cox regression analysis showed that 6 lncRNAs (FOXE1, HOXB13-AS1_2, VMO1, HIST1H3F, AJ003147.8, ASXL3) were retrieved to construct a predictive model associated with overall survival in LUAD patients. Combined DNA methylation and gene expression survival analysis revealed that 4 lncRNAs (AC023824.1, AF186192.1, LINC01354 and WASIR2) and 8 mRNAs (S1PR1, CCDC181, F2RL1, EFS, KLHDC9, MPV17L, GKN2, ITPRIPL1) might act as independent biomarkers for the prognosis of LUAD.

Conclusions

Methylation-driven lncRNA and mRNA contribute to the survival of LUAD, and 4 lncRNAs and 8 mRNAs might be potential biomarkers for the prognosis of LUAD.

Long noncoding RNA FAM3D-AS1 inhibits development of colorectal cancer through NF-κB signaling pathway

Although numerous differential long noncoding RNAs (IncRNAs) have been identified, the relationship between lncRNA and colorectal cancer (CRC) still remains largely unclear. In the present study, we investigated the function and provided a possible mechanism of lncRNA FAM3D-AS1 in CRC. CCK8, transwell, and trypan blue staining were used to evaluate the proliferation, invasion, and cell death rates. Real-time PCR was used to elucidate the expression level of FAM3D-AS1. We found that lncRNA FAM3D-AS1 located in cytoplasm. Overexpression of FAM3D-AS1 significantly inhibited the cell proliferation, cell survival rates, and invaded cells. We also provided evidence that FAM3D-AS1 reversed the EMT process. Moreover, we proved that FAM3D-AS1 inhibits CRC development through NF-κB signaling pathway. Taken together, we performed functional analysis of FAM3D-AS1 and provided a possible mechanism in the development of CRC. Our study provided new targets for clinical treatment.

Long non-coding RNAs in retinoblastoma

Retinoblastoma represents 3% of all childhood cancers and is the most common intraocular malignant tumor with a highly aggressive and metastatic phenotype. While recent genetic and epigenetic studies have reported new insights into the mechanism of retinoblastoma development, the involvement of regulatory non-coding RNAs remains unclear. Long non-coding RNAs (lncRNAs) are a group of endogenous non-protein-coding RNAs with the capacity to regulate gene expression at multiple levels. Recent evidence has shown that lncRNAs can regulate many cellular processes, such as cell proliferation, differentiation, migration, and invasion. Several lncRNAs, including BANCR, AFAP1-AS1, NEAT1, XIST, ANRIL, PlncRNA-1, HOTAIR, PANDAR, DANCR, and THOR, promote the progression and metastasis of retinoblastoma. However, some lncRNAs, such as MEG3, MT1JP, and H19, play a tumor suppressive role. Our review summarizes the functional role of lncRNAs in retinoblastoma and their potential clinical applications for diagnosis, prognosis, and treatment.

The Function of Non-Coding RNAs in Lung Cancer Tumorigenesis

Lung cancer is the most prevalent and deadliest cancer worldwide. A significant part of lung cancer studies is dedicated to the expression alterations of non-coding RNAs. The non-coding RNAs are transcripts that cannot be translated into proteins. While the study of microRNAs and siRNAs in lung cancer received a lot of attention over the last decade, highly efficient therapeutic option or the diagnostic methods based on non-coding RNAs are still lacking. Because of this, it is of utmost importance to direct future research on lung cancer towards analyzing other RNA types for which the currently available data indicates that are essential at modulating lung tumorigenesis. Through our review of studies on this subject, we identify the following non-coding RNAs as tumor suppressors: ts-46, ts-47, ts-101, ts-53, ts-3676, ts-4521 (tRNA fragments), SNORD116-26, HBII-420, SNORD15A, SNORA42 (snoRNAs), piRNA-like-163, piR-35127, the piR-46545 (piRNAs), CHIAP2, LOC100420907, RPL13AP17 (pseudogenes), and uc.454 (T-UCR). We also found non-coding RNAs with tumor-promoting function: tRF-Leu-CAG, tRNA-Leu, tRNA-Val (tRNA fragments), circ-RAD23B, circRNA 100146, circPVT1, circFGFR3, circ_0004015, circPUM1, circFLI1, circABCB10, circHIPK3 (circRNAs), SNORA42, SNORA3, SNORD46, SNORA21, SNORD28, SNORA47, SNORD66, SNORA68, SNORA78 (snoRNAs), piR-65, piR-34871, piR-52200, piR651 (piRNAs), hY4 5’ fragments (YRNAs), FAM83A-AS1, WRAP53, NKX2-1-AS1 (NATs), DUXAP8, SFTA1P (pseudogene transcripts), uc.338, uc.339 (T-UCRs), and hTERC.

LINC01433/miR-2116-3p/MYC Feedback Loop Promotes Cell Proliferation, Migration, and the Epithelial-Mesenchymal Transition in Breast Cancer

Background: It is reported that long noncoding RNAs play an important role in human cancers, including breast cancer (BC). However, the effect of long intergenic non-protein coding RNA 1433 (LINC01433) on BC development remains elusive. Materials and Methods: The expression level of LINC01433 in BC cells and a normal breast epithelial cell (MCF-10A) was determined by quantitative real-time polymerase chain reaction (qRT-PCR). A series of functional assays was applied to measure the bio-function of LINC01433 in BC. Bioinformatics analysis and mechanistic assays were utilized to disclose the underlying mechanism involved in the LINC01433-mediated BC cellular process. Results: qRT-PCR revealed that LINC01433 was highly expressed in BC cells. In function, LINC01433 depletion suppressed BC cell proliferation, migration, and epithelial-mesenchymal transition, but induced cell apoptosis. Mechanically, chromatin immunoprecipitation and luciferase reporter assays suggested that LINC01433 was activated by its upstream transcription factor MYC proto-oncogene (MYC). The interaction between LINC01433 and miR-2116-3p was verified in BC. Additionally, MYC was validated as a target gene of miR-2116-3p. Rescue assays demonstrated that LINC01433 promoted BC cellular process via regulating miR-2116-3p/MYC axis. Conclusion: Our findings revealed a novel positive feedback loop (LINC01433/miR-2116-3p/MYC) in BC progression and discovered the novel functional genes in this BC cellular process.