A feed-forward regulatory loop between androgen receptor and PlncRNA-1 promotes prostate cancer progression

Crosstalk between lncRNAs and Wnt/β-catenin signaling pathways in lung cancers: From cancer progression to therapeutic response

Lung cancer (LC) is considered to have the highest mortality rate around the world. Because there are no early diagnostic signs or efficient clinical alternatives, distal metastasis and increasing numbers of recurrences are a challenge in the clinical management of LC. Long non-coding RNAs (lncRNAs) have recently been recognized as a critical regulator involved in the progression and treatment response to LC. The Wnt/β-catenin pathway has been shown to influence LC occurrence and progress. Therefore, discovering connections between Wnt signaling pathway and lncRNAs may offer new therapeutic targets for improving LC treatment and management. In this review, the purpose of this article is to present possible therapeutic approaches by reviewing particular relationships, key processes, and molecules associated to the beginning and development of LC.

The RNA secondary structure of androgen receptor-FL and V7 transcripts reveals novel regulatory regions

The androgen receptor (AR) is a ligand-dependent nuclear transcription factor belonging to the steroid hormone nuclear receptor family. Due to its roles in regulating cell proliferation and differentiation, AR is tightly regulated to maintain proper levels of itself and the many genes it controls. AR dysregulation is a driver of many human diseases including prostate cancer. Though this dysregulation often occurs at the RNA level, there are many unknowns surrounding post-transcriptional regulation of AR mRNA, particularly the role that RNA secondary structure plays. Thus, a comprehensive analysis of AR transcript secondary structure is needed. We address this through the computational and experimental analyses of two key isoforms, full length (AR-FL) and truncated (AR-V7). Here, a combination of in-cell RNA secondary structure probing experiments (targeted DMS-MaPseq) and computational predictions were used to characterize the static structural landscape and conformational dynamics of both isoforms. Additionally, in-cell assays were used to identify functionally relevant structures in the 5' and 3' UTRs of AR-FL. A notable example is a conserved stem loop structure in the 5'UTR of AR-FL that can bind to Poly(RC) Binding Protein 2 (PCBP2). Taken together, our results reveal novel features that regulate AR expression.

Long non-coding RNAs in cancer: multifaceted roles and potential targets for immunotherapy

Cancer remains a major global health concern with high mortality rates mainly due to late diagnosis and poor prognosis. Long non-coding RNAs (lncRNAs) are emerging as key regulators of gene expression in human cancer, functioning through various mechanisms including as competing endogenous RNAs (ceRNAs) and indirectly regulating miRNA expression. LncRNAs have been found to have both oncogenic and tumor-suppressive roles in cancer, with the former promoting cancer cell proliferation, migration, invasion, and poor prognosis. Recent research has shown that lncRNAs are expressed in various immune cells and are involved in cancer cell immune escape and the modulation of the tumor microenvironment, thus highlighting their potential as targets for cancer immunotherapy. Targeting lncRNAs in cancer or immune cells could enhance the anti-tumor immune response and improve cancer immunotherapy outcomes. However, further research is required to fully understand the functional roles of lncRNAs in cancer and the immune system and their potential as targets for cancer immunotherapy. This review offers a comprehensive examination of the multifaceted roles of lncRNAs in human cancers, with a focus on their potential as targets for cancer immunotherapy. By exploring the intricate mechanisms underlying lncRNA-mediated regulation of cancer cell proliferation, invasion, and immune evasion, we provide insights into the diverse therapeutic applications of these molecules.

Molecular Mechanisms of Prostate Cancer Development in the Precision Medicine Era: A Comprehensive Review

The progression of prostate cancer (PCa) relies on the activation of the androgen receptor (AR) by androgens. Despite efforts to block this pathway through androgen deprivation therapy, resistance can occur through several mechanisms, including the abnormal activation of AR, resulting in castration-resistant PCa following the introduction of treatment. Mutations, amplifications, and splicing variants in AR-related genes have garnered attention in this regard. Furthermore, recent large-scale next-generation sequencing analysis has revealed the critical roles of AR and AR-related genes, as well as the DNA repair, PI3K, and cell cycle pathways, in the onset and progression of PCa. Moreover, research on epigenomics and microRNA has increasingly become popular; however, it has not translated into the development of effective therapeutic strategies. Additionally, treatments targeting homologous recombination repair mutations and the PI3K/Akt pathway have been developed and are increasingly accessible, and multiple clinical trials have investigated the efficacy of immune checkpoint inhibitors. In this comprehensive review, we outline the status of PCa research in genomics and briefly explore potential future developments in the field of epigenetic modifications and microRNAs.

A thorough understanding of the role of lncRNA in prostate cancer pathogenesis; Current knowledge and future research directions

In the entire world, prostate cancer (PCa) is one of the most common and deadly cancers. Treatment failure is still common among patients, despite PCa diagnosis and treatment improvements. Inadequate early diagnostic markers and the emergence of resistance to conventional therapeutic approaches, particularly androgen-deprivation therapy, are the causes of this. Long non-coding RNAs (lncRNAs), as an essential group of regulatory molecules, have been reported to be dysregulated through prostate tumorigenesis and hold great promise as diagnostic targets. Besides, lncRNAs regulate the malignant features of PCa cells, such as proliferation, invasion, metastasis, and drug resistance. These multifunctional RNA molecules interact with other molecular effectors like miRNAs and transcription factors to modulate various signaling pathways, including AR signaling. This study aimed to compile new knowledge regarding the role of lncRNA through prostate tumorigenesis in terms of their effects on the various malignant characteristics of PCa cells; in light of these characteristics and the significant potential of lncRNAs as diagnostic and therapeutic targets for PCa. AVAILABILITY OF DATA AND MATERIALS: Not applicable.

Non-coding RNAs in enzalutamide resistance of castration-resistant prostate cancer

Enzalutamide (Enz) is a next-generation androgen receptor (AR) antagonist used to treat castration-resistant prostate cancer (CRPC). Unfortunately, the relapsing nature of CRPC results in the development of Enz resistance in many patients. Non-coding RNAs (ncRNAs) are RNA molecules that do not encode proteins, which include microRNAs (miRNA), long ncRNAs (lncRNAs), circular RNAs (circRNAs), and other ncRNAs with known and unknown functions. Recently, dysregulation of ncRNAs in CRPC, particularly their regulatory function in drug resistance, has attracted more and more attention. Herein, we introduce the roles of dysregulation of different ncRNAs subclasses in the development of CRPC progression and Enz resistance. Recently determined mechanisms of Enz resistance are discussed, focusing mainly on the role of AR-splice variant-7 (AR-V7), mutations, circRNAs and lncRNAs that act as miRNA sponges. Also, the contributions of epithelial-mesenchymal transition and glucose metabolism to Enz resistance are discussed. We summarize the different mechanisms of miRNAs, lncRNAs, and circRNAs in the progression of CRPC and Enz resistance, and highlight the prospect of future therapeutic strategies against Enz resistance.

Crosstalk between epigenetics and tumor promoting androgen signaling in prostate cancer

Prostate cancer (PCa) is one of the major health burdens among all cancer types in men globally. Early diagnosis and efficacious treatment options are highly warranted as far as the incidence of PCa is concerned. Androgen-dependent transcriptional activation of androgen receptor (AR) is central to the prostate tumorigenesis and therefore hormonal ablation therapy remains the first line of treatment for PCa in the clinics. However, the molecular signaling engaged in AR-dependent PCa initiation and progression is infrequent and diverse. Moreover, apart from the genomic changes, non-genomic changes such as epigenetic modifications have also been suggested as critical regulator of PCa development. Among the non-genomic mechanisms, various epigenetic changes such as histones modifications, chromatin methylation and noncoding RNAs regulations etc. play decisive role in the prostate tumorigenesis. Given that epigenetic modifications are reversible using pharmacological modifiers, various promising therapeutic approaches have been designed for the better management of PCa. In this chapter, we discuss the epigenetic control of tumor promoting AR signaling that underlies the mechanism of prostate tumorigenesis and progression. In addition, we have discussed the approaches and opportunities to develop novel epigenetic modifications based therapeutic strategies for targeting PCa including castrate resistant prostate cancer (CRPC).

Molecular Mechanisms of Noncoding RNA in the Occurrence of Castration-Resistant Prostate Cancer

Although several therapeutic options have been shown to improve survival of most patients with prostate cancer, progression to castration-refractory state continues to present challenges in clinics and scientific research. As a highly heterogeneous disease entity, the mechanisms of castration-resistant prostate cancer (CRPC) are complicated and arise from multiple factors. Among them, noncoding RNAs (ncRNAs), the untranslated part of the human transcriptome, are closely related to almost all biological regulation, including tumor metabolisms, epigenetic modifications and immune escape, which has encouraged scientists to investigate their role in CRPC. In clinical practice, ncRNAs, especially miRNAs and lncRNAs, may function as potential biomarkers for diagnosis and prognosis of CRPC. Therefore, understanding the molecular biology of CRPC will help boost a shift in the treatment of CRPC patients. In this review, we summarize the recent findings of miRNAs and lncRNAs, discuss their potential functional mechanisms and highlight their clinical application prospects in CRPC.

The Role and Mechanism of Long Non-Coding RNA HOTAIR in the Oncogenesis, Diagnosis, and Treatment of Head and Neck Squamous Cell Carcinoma

The most frequent malignant tumor of the head and neck is head and neck squamous cell carcinoma (HNSCC), which has a high frequency, a poor prognosis in the late stages, and subpar therapeutic results. As a result, early HNSCC diagnosis and treatment are urgently needed; however, there are no good diagnostic biomarkers or efficient therapeutic targets at this time. The long-stranded non-coding RNA HOTAIR may be important in the pathogenesis of cancer, according to recent research. By interactions with DNA, RNA, and proteins, it has been demonstrated that HOTAIR, a >200 nucleotide RNA transcript, plays a role in the biological processes of many types of tumor cells, including proliferation, metastasis, and prognosis of HNSCC. Hence, this review discusses HOTAIR's function and molecular mechanisms in HNSCC.

Long noncoding RNA CBR3-AS1 mediates tumorigenesis and radiosensitivity of non-small cell lung cancer through redox and DNA repair by CBR3-AS1 /miR-409-3p/SOD1 axis

The long noncoding RNA CBR3-AS1 has important functions in various cancers. However, the biological functions of CBR3-AS1 in non-small cell lung cancer (NSCLC) remain unclear. This study aimed to investigate the roles and molecular mechanisms of CBR3-AS1 in NSCLC tumorigenesis and radiosensitivity. Here, we demonstrate CBR3-AS1 overexpression in NSCLC tissue compared with adjacent normal tissue. CBR3-AS1 downregulation reduced proliferation, invasion, and migration; inhibited cell cycle progression; and promoted apoptosis of NSCLC cells. CBR3-AS1 also promoted tumor growth in vivo. CBR3-AS1 may regulate the expression and functions of the miR-409-3p target gene SOD1. CBR3-AS1 expression was negatively correlated with radiosensitivity. CBR3-AS1 downregulation decreased post-irradiation SOD1 expression, increased γH2AX formation, raised levels of reactive oxygen species, and promoted apoptosis. Our results suggest that CBR3-AS1 functions as an oncogene through the CBR3-AS1/miR-409-3p/SOD1 pathway, and may represent a new therapeutic target, especially to regulate radiosensitivity in NSCLC.

Crosstalk between Long Non Coding RNAs, microRNAs and DNA Damage Repair in Prostate Cancer: New Therapeutic Opportunities?

Simple Summary

Non-coding RNAs are a type of genetic material that doesn’t make protein, but performs diverse regulatory functions. In prostate cancer, most treatments target proteins, and resistance to such therapies is common, leading to disease progression. Targeting non-coding RNAs may provide alterative treatment options and potentially overcome drug resistance. Major types of non-coding RNAs include tiny ‘microRNAs’ and much longer ‘long non-coding RNAs’. Scientific studies have shown that these form a major part of the human genome, and play key roles in altering gene activity and determining the fate of cells. Importantly, in cancer, their activity is altered. Recent evidence suggests that microRNAs and long non-coding RNAs play important roles in controlling response to DNA damage. In this review, we explore how different types of non-coding RNA interact to control cell DNA damage responses, and how this knowledge may be used to design better prostate cancer treatments and tests.

Abstract

It is increasingly appreciated that transcripts derived from non-coding parts of the human genome, such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), are key regulators of biological processes both in normal physiology and disease. Their dysregulation during tumourigenesis has attracted significant interest in their exploitation as novel cancer therapeutics. Prostate cancer (PCa), as one of the most diagnosed malignancies and a leading cause of cancer-related death in men, continues to pose a major public health problem. In particular, survival of men with metastatic disease is very poor. Defects in DNA damage response (DDR) pathways culminate in genomic instability in PCa, which is associated with aggressive disease and poor patient outcome. Treatment options for metastatic PCa remain limited. Thus, researchers are increasingly targeting ncRNAs and DDR pathways to develop new biomarkers and therapeutics for PCa. Increasing evidence points to a widespread and biologically-relevant regulatory network of interactions between lncRNAs and miRNAs, with implications for major biological and pathological processes. This review summarises the current state of knowledge surrounding the roles of the lncRNA:miRNA interactions in PCa DDR, and their emerging potential as predictive and diagnostic biomarkers. We also discuss their therapeutic promise for the clinical management of PCa.

The Crosstalk of Long Non-Coding RNA and MicroRNA in Castration-Resistant and Neuroendocrine Prostate Cancer: Their Interaction and Clinical Importance

Prostate cancer is featured by its heterogeneous nature, which indicates a different prognosis. Castration-resistant prostate cancer (CRPC) is a hallmark of the treatment-refractory stage, and the median survival of patients is only within two years. Neuroendocrine prostate cancer (NEPC) is an aggressive variant that arises from de novo presentation of small cell carcinoma or treatment-related transformation with a median survival of 1–2 years from the time of diagnosis. The epigenetic regulators, such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), have been proven involved in multiple pathologic mechanisms of CRPC and NEPC. LncRNAs can act as competing endogenous RNAs to sponge miRNAs that would inhibit the expression of their targets. After that, miRNAs interact with the 3’ untranslated region (UTR) of target mRNAs to repress the step of translation. These interactions may modulate gene expression and influence cancer development and progression. Otherwise, epigenetic regulators and genetic mutation also promote neuroendocrine differentiation and cancer stem-like cell formation. This step may induce neuroendocrine prostate cancer development. This review aims to provide an integrated, synthesized overview under current evidence to elucidate the crosstalk of lncRNAs with miRNAs and their influence on castration resistance or neuroendocrine differentiation of prostate cancer. Notably, we also discuss the mechanisms of lncRNA–miRNA interaction in androgen receptor-independent prostate cancer, such as growth factors, oncogenic signaling pathways, cell cycle dysregulation, and cytokines or other transmembrane proteins. Conclusively, we underscore the potential of these communications as potential therapeutic targets in the future.

Roles of Key Epigenetic Regulators in the Gene Transcription and Progression of Prostate Cancer

Prostate cancer (PCa) is a top-incidence malignancy, and the second most common cause of death amongst American men and the fifth leading cause of cancer death in men around the world. Androgen receptor (AR), the key transcription factor, is critical for the progression of PCa by regulating a series of target genes by androgen stimulation. A number of co-regulators of AR, including co-activators or co-repressors, have been implicated in AR-mediated gene transcription and PCa progression. Epigenetic regulators, by modifying chromatin integrity and accessibility for transcription regulation without altering DNA sequences, influence the transcriptional activity of AR and further regulate the gene expression of AR target genes in determining cell fate, PCa progression and therapeutic response. In this review, we summarized the structural interaction of AR and epigenetic regulators including histone or DNA methylation, histone acetylation or non-coding RNA, and functional synergy in PCa progression. Importantly, epigenetic regulators have been validated as diagnostic markers and therapeutic targets. A series of epigenetic target drugs have been developed, and have demonstrated the potential to treat PCa alone or in combination with antiandrogens.

Interaction between Non-Coding RNAs and Androgen Receptor with an Especial Focus on Prostate Cancer

The androgen receptor (AR) is a member of the nuclear receptor superfamily and has three functional domains, namely the N-terminal, DNA binding, and C-terminal domain. The N-terminal domain harbors potent transactivation functions, whereas the C-terminal domain binds to androgens and antiandrogens used to treat prostate cancer. AR has genomic activity being DNA binding-dependent or through interaction with other DNA-bound transcription factors, as well as a number of non-genomic, non-canonical functions, such as the activation of the ERK, AKT, and MAPK pathways. A bulk of evidence indicates that non-coding RNAs have functional interactions with AR. This type of interaction is implicated in the pathogenesis of human malignancies, particularly prostate cancer. In the current review, we summarize the available data on the role of microRNAs, long non-coding RNAs, and circular RNAs on the expression of AR and modulation of AR signaling, as well as the effects of AR on their expression. Recognition of the complicated interaction between non-coding RNAs and AR has practical importance in the design of novel treatment options, as well as modulation of response to conventional therapeutics.

AC016745.3 Regulates the Transcription of AR Target Genes by Antagonizing NONO

The androgen receptor (AR) and its related signaling pathways play an important role in the development of prostate cancer (PCa). Long non-coding RNAs (lncRNAs) are involved in the regulation of tumorigenesis and development, but their specific mechanism of action remains unclear. This study examines the function and mechanisms of action of lncRNA AC016745.3 in the development of PCa. It shows that dihydrotestosterone (DHT) results in the AR-dependent suppression of AC016745.3 expression in the LNCaP androgen-sensitive human prostate adenocarcinoma cell line. In addition, overexpression of AC016745.3 inhibits the proliferation and migration of PCa cells, and suppresses the expression of AR target genes. This research also demonstrates that the protein NONO interacts with AR and functions as an AR co-activator, promoting AR transcriptional activity. Furthermore, using RNA immunoprecipitation (RIP)-PCR experiments, the study demonstrates that both NONO and AR can bind AC016745.3. Moreover, cell phenotypic experiments reveal that NONO can promote cellular proliferation and migration, and that AC016745.3 can partially antagonize the pro-oncogenic functions of NONO in PCa cells. In summary, the results indicate that AC016745.3 can bind NONO, suppressing its ability to promote AR-dependent transcriptional activity. Furthermore, DHT-dependent suppression of AC016745.3 expression can enhance NONO's promotion effect on AR.

Natural Product-Based Studies for the Management of Castration-Resistant Prostate Cancer: Computational to Clinical Studies

Background: With prostate cancer being the fifth-greatest cause of cancer mortality in 2020, there is a dire need to expand the available treatment options. Castration-resistant prostate cancer (CRPC) progresses despite androgen depletion therapy. The mechanisms of resistance are yet to be fully discovered. However, it is hypothesized that androgens depletion enables androgen-independent cells to proliferate and recolonize the tumor. Objectives: Natural bioactive compounds from edible plants and herbal remedies might potentially address this need. This review compiles the available cheminformatics-based studies and the translational studies regarding the use of natural products to manage CRPC. Methods: PubMed and Google Scholar searches for preclinical studies were performed, while ClinicalTrials.gov and PubMed were searched for clinical updates. Studies that were not in English and not available as full text were excluded. The period of literature covered was from 1985 to the present. Results and Conclusion: Our analysis suggested that natural compounds exert beneficial effects due to their broad-spectrum molecular disease-associated targets. In vitro and in vivo studies revealed several bioactive compounds, including rutaecarpine, berberine, curcumin, other flavonoids, pentacyclic triterpenoids, and steroid-based phytochemicals. Molecular modeling tools, including machine and deep learning, have made the analysis more comprehensive. Preclinical and clinical studies on resveratrol, soy isoflavone, lycopene, quercetin, and gossypol have further validated the translational potential of the natural products in the management of prostate cancer.

Long noncoding RNA GAS5 interacts and suppresses androgen receptor activity in prostate cancer cells

The androgen receptor (AR) plays an important role in the progression of prostate cancer and is the most important therapeutic target. However, androgen deprivation therapy will finally lead patients to progress to castration-resistant prostate cancer (CRPC). Here, we confirmed that GAS5, a long noncoding RNA, could interact and suppress AR transactivation in CRPC C4-2 cells. Knockdown GAS5 by short hairpin RNA would enhance the transcription of AR via promote AR recruitment to the promoter of its downstream target genes. Functionally, GAS5 overexpression inhibits cell proliferation partially through inhibiting AR transactivation in C4-2 cells. Moreover, knocking down GAS5 protects C4-2 cells from the docetaxel-induced cell apoptosis. In return, the suppressed AR was found to downregulate the GAS5 expression, which forms a feedback loop resulted in AR high transcription activity in CRPC. Collectively, our findings revealed the important role of GAS5 in AR axis activity regulation and CRPC progression. Targeting GAS5 to intervene the feedback loop might be a new potential therapeutic approach for the patients at CRPC stage.

Retinoic Acid Downregulates HSPB8 Gene Expression in Human Breast Cancer Cells MCF-7

Breast cancer (BC) is a serious and widespread disease for which different treatments have been developed. In addition to the classic therapies, the treatment with retinoic acid (RA) is still being clinically investigated. RA reduces cancer cells proliferation and migration, but its molecular mechanism of action is not clear. In tumor development, autophagy promotes cancer cell survival and prevents apoptosis. Small heat shock protein B8 (HSPB8) acts together with its co-chaperone BCL-2 associated athanogene 3 (BAG3) stimulating BC proliferation and migration. We analyzed whether direct correlations exist between RA and HSPB8 or BAG3 and how this may play a role in BC. We measured HSPB8 and BAG3 gene expression in MCF-7 BC cells and we analyzed the potential correlation between the antiproliferative and antimigratory effect of RA with the expression level of HSPB8. We found that in MCF-7 cells RA reduces both HSPB8 and BAG3 gene expression and it alters the mitotic spindle organization. Notably, the effects of RA on HSPB8 levels are exerted at both transcriptional and translational levels. RA effects are possibly mediated by miR-574-5p that targets the HSPB8 transcript. Our results suggest that therapeutic doses of RA can efficiently counteract the adverse effects of HSPB8 in BC progression.

LncRNA PlncRNA-1 accelerates the progression of prostate cancer by regulating PTEN/Akt axis

Long non-coding RNAs are key regulators of tumor development and progression, with the potential to be biomarkers of tumors. This study aimed to explore the role of PlncRNA-1 in the progression of prostate cancer (PCa). We found that PlncRNA-1 was up-regulated in 85.29% of PCa tissues and could predict the T stage of PCa patients to a certain extent. Results showed that inhibition of PlncRNA-1 expression potentially promoted cell apoptosis, suppressed the proliferation, migration, and invasion of cells, and triggered G2/M cycle arrest in vitro and in vivo. PlncRNA-1 was mainly localized in the nucleus and PlncRNA-1 expression and phosphatase and tensin homologue (PTEN) expression were negatively correlated. Mechanistically, knockdown of PlncRNA-1 increased expression levels of PTEN protein and phosphorylated PTEN protein, and decreased expression levels of Akt protein and phosphorylated Akt protein. Rescue experiments demonstrated that PTEN inhibitors abolished the changes in PTEN/Akt pathway caused by PlncRNA-1 interference. PlncRNA-1 can promote the occurrence and development of PCa via the PTEN/Akt pathway. PlncRNA-1 may, therefore, be a new candidate target for the treatment of PCa.

Androgen Receptor-Related Non-coding RNAs in Prostate Cancer

Prostate cancer (PCa) is the second leading cause of cancer-related death among men in the United States. Androgen receptor (AR) signaling is the dominant oncogenic pathway in PCa and the main strategy of PCa treatment is to control the AR activity. A large number of patients acquire resistance to Androgen deprivation therapy (ADT) due to AR aberrant activation, resulting in castration-resistant prostate cancer (CRPC). Understanding the molecular mechanisms underlying AR signaling in the PCa is critical to identify new therapeutic targets for PCa patients. The recent advances in high-throughput RNA sequencing (RNA-seq) techniques identified an increasing number of non-coding RNAs (ncRNAs) that play critical roles through various mechanisms in different diseases. Some ncRNAs have shown great potentials as biomarkers and therapeutic targets. Many ncRNAs have been investigated to regulate PCa through direct association with AR. In this review, we aim to comprehensively summarize recent findings of the functional roles and molecular mechanisms of AR-related ncRNAs as AR regulators or targets in the progression of PCa.

Construction of a ceRNA-based lncRNA-mRNA network to identify functional lncRNAs in polycystic ovarian syndrome

Polycystic ovary syndrome (PCOS) is a prevalent endocrine and metabolic disorder in women of childbearing age. Recent studies suggest important roles for lncRNAs in PCOS development. Based on the hypothesis that lncRNAs are able to regulate mRNA functions by competitive binding to shared miRNAs, the present work sought to construct a PCOS-related lncRNA-mRNA network (PCLMN) to identify key lncRNAs with dysregulated expression and potential prognostic and therapeutic relevance. A global background network was constructed after retrieving lncRNA-miRNA and miRNA-mRNA pairs from the lncRNASNP2, miRTarBase and StarBase databases. Based on gene expression profiles from ovarian granulosa cells from PCOS patients and controls in the GEO’s GSE95728 dataset, the PCLMN was then constructed by applying hypergeometric testing. Using topological analysis, we identified 3 lncRNAs (LINC00667, AC073172.1 and H19) ranking within the top-ten gene lists for all three centrality measures. We then explored their subcellular localization, performed functional module analyses, and identified 4 sex hormone-related transcription factors as potential regulators of their expression. Significant associations with inflammation, oxidative stress, and apoptosis-related processes and pathways were revealed for the key lncRNAs in our PCMLN. Further studies verifying the mRNA/lncRNA relationships identified herein are needed to clarify their clinical significance.

LncRNA CBR3-AS1 regulates of breast cancer drug sensitivity as a competing endogenous RNA through the JNK1/MEK4-mediated MAPK signal pathway

Background

Adriamycin (ADR) resistance is one of the main obstacles to improving the clinical prognosis of breast cancer patients. Long noncoding RNAs (lncRNAs) can regulate cell behavior, but the role of these RNAs in the anti-ADR activity of breast cancer remains unclear. Here, we aim to investigate the imbalance of a particular long noncoding RNA, lncRNA CBR3 antisense RNA 1 (CBR3-AS1), and its role in ADR resistance.

Methods

Microarray analysis of ADR-resistant breast cancer cells was performed to identify CBR3-AS1. CCK-8 and colony formation assays were used to detect the sensitivity of breast cancer cells to ADR. Dual-luciferase reporter, RNA pulldown, IHC and western blot analyses were used to verify the relationship between the expression of CBR3-AS1, miRNA and target genes. For in vivo experiments, the effect of CBR3-AS1 on breast cancer resistance was observed in a xenograft tumor model. The role of CBR3-AS1 in influencing ADR sensitivity was verified by clinical breast cancer specimens from the TCGA, CCLE, and GDSC databases.

Results

We found that CBR3-AS1 expression was significantly increased in breast cancer tissues and was closely correlated with poor prognosis. CBR3-AS1 overexpression promoted ADR resistance in breast cancer cells in vitro and in vivo. Mechanistically, we identified that CBR3-AS1 functioned as a competitive endogenous RNA by sponging miR-25-3p. MEK4 and JNK1 of the MAPK pathway were determined to be direct downstream proteins of the CBR3-AS1/miR-25-3p axis in breast cancer cells.

Conclusions

In summary, our findings demonstrate that CBR3-AS1 plays a critical role in the chemotherapy resistance of breast cancer by mediating the miR-25-3p and MEK4/JNK1 regulatory axes. The potential of CBR3-AS1 as a targetable oncogene and therapeutic biomarker of breast cancer was identified.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-01844-7.

LncRNA SBF2-AS1 Promotes Diffuse Large B-Cell Lymphoma Growth by Regulating FGFR2 via Sponging miR-494-3p

Purpose

Currently, there is no efficient and feasible method for diffuse large B-cell lymphoma (DLBCL) in clinical practice, and the main reason is the unclear pathogenesis of DLBCL, which leads to a high fatality rate of DLBCL.

Methods

Therefore, it is meaningful to explore the molecular mechanism of DLBCL and find a targeted therapeutic approach from the molecular level.

Results

Long non-coding RNA (lncRNA) SBF2-AS1 was highly expressed in DLBCL tissues and cell lines. Silencing of SBF2-AS1 inhibited the viability and growth of OCI-LY-3 cells. Furthermore, SBF2-AS1 acted as a sponge of miR-494-3p and inhibited its expression. And miR-494-3p directly targeted FGFR2. Functionally, forced expression of miR-494-3p or knockdown of FGFR2 removed the promoted effects of lncRNA SBF2-AS1 on DLBCL development. In vivo tumorigenesis experiments indicated SBF2-AS1 accelerated tumor growth via miR-494-3p/FGFR2 axis.

Conclusion

Our study revealed that SBF2-AS1 promoted the growth of DLBCL, which were mediated by miR-494-3p/FGFR2 axis.

Hypomethylation of PlncRNA-1 promoter enhances bladder cancer progression through the miR-136-5p/Smad3 axis

Apart from being potential prognostic biomarkers and therapeutic targets, long non-coding RNAs (lncRNAs) modulate the development and progression of multiple cancers. PlncRNA-1 is a newly discovered lncRNA that exhibits the above properties through multiple regulatory pathways. However, the clinical significance and molecular mechanisms of PlncRNA-1 in bladder cancer have not been established. PlncRNA-1 was found to be overexpressed in 71.43% of bladder cancer tissues. Moreover, the expression level correlated with tumor invasion, T stage, age, and number of tumors, but not with gender, recurrent status, preoperative treatment, pathological grade, and tumor size. The expression level of PlncRNA-1 can, to a certain extent, be used as a predictor of the degree of tumor invasion and T stage among BC patients. Inhibiting PlncRNA-1 expression impaired the proliferation, migration, and invasion of T24 and 5637 bladder cancer cells in vitro and in vivo. Specifically, PlncRNA-1 promoter in BC tissues was found to be hypomethylated at position 131 (36157603 on chromosome 21). PlncRNA-1 promoter hypomethylation induces the overexpression of PlncRNA-1. In addition, PlncRNA-1 modulated the expression of smad3 and has-miR-136-5p (miR-136). Conversely, miR-136 regulated the expression of PlncRNA-1 and smad3. PlncRNA-1 mimics competitive endogenous RNA (ceRNA) in its regulation of smad3 expression by binding miR-136. Rescue analysis further revealed that modulation of miR-136 could reverse the expression of smad3 and epithelial–mesenchymal transition (EMT) marker proteins impaired by PlncRNA-1. In summary, PlncRNA-1 has important clinical predictive values and is involved in the post-transcriptional regulation of smad3. The PlncRNA-1/miR-136/smad3 axis provides insights into the regulatory mechanism of BC, thus may serve as a potential therapeutic target and prognostic biomarker for cancer.

Aerobic exercise ameliorates benign prostatic hyperplasia in obese mice through downregulating the AR/androgen/PI3K/AKT signaling pathway

OBJECTIVE

Emerging evidence has suggested that physical activities can reduce the risk of benign prostatic hyperplasia (BPH). Here, we evaluated the effect of aerobic exercise in a model of BPH using obese mice.

METHODS

Obese C57BL/6J mice in the control group, obesity group (OB), and obesity group plus exercise (OB + E) with eight weeks training were inspected for morphological alterations via hematoxylin-eosin (H&E) staining, lipid and sex hormone metabolites via enzyme-linked immunosorbent assays (ELISAs), relative protein expression via Western blotting, and prostate cancer-up-regulated long noncoding RNA (PlncRNA) and androgen receptor (AR) mRNA levels via quantitative real-time PCR (qRT-PCR).

RESULTS

Aerobic exercise training slowed fat-mass gain in OB mice. Prostate volume (PV) and area of lumen was significantly decreased in OB mice and was slightly increased following aerobic exercise. Epithelial volume density in the OB group was higher than that in the control group. Furthermore, aerobic exercise lowered serum low-density lipoprotein (LDL), triglyceride, and free fatty acid (FFA) levels, whereas it raised high-density lipoprotein (HDL) levels in OB + E mice. Additionally, the hormonal ratio of estradiol/testosterone (E2/T) approached that of the control group following aerobic exercise in OB + E mice. Mechanistically, aerobic exercise downregulated the PlncRNA-AR/androgen signaling pathway via the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) axis in the prostates of OB + E mice.

CONCLUSION

These data demonstrate that aerobic exercise may alleviate BPH in obese mice through regulation of the AR/androgen/PI3K/AKT signaling pathway.

Roles of long non-coding RNAs in the hallmarks of glioma

Glioma is one of the most common types of tumor of the central nervous system. Due to the aggressiveness and invasiveness of high-level gliomas, the survival time of patients with these tumors is short, at ~15 months, even after combined treatment with surgery, radiotherapy and/or chemotherapy. Recently, a number of studies have demonstrated that long non-coding RNA (lncRNAs) serve crucial roles in the multistep development of human gliomas. Gliomas acquire numerous biological abilities during multistep development that collectively constitute the hallmarks of glioma. Thus, in this review, the roles of lncRNAs associated with glioma hallmarks and the current and future prospects for their development are summarized.

LINC00675 activates androgen receptor axis signaling pathway to promote castration-resistant prostate cancer progression

The development of prostate cancer (PCa) from androgen-deprivation therapy (ADT) sensitive to castration resistant (CRPC) seriously impacts life quality and survival of PCa patients. Emerging evidence shows that long noncoding RNAs (lncRNAs) play vital roles in cancer initiation and progression. However, the inherited mechanisms of how lncRNAs participate in PCa progression and treatment resistance remain unclear. Here, we found that a long noncoding RNA LINC00675 was upregulated in androgen-insensitive PCa cell lines and CRPC patients, which promoted PCa progression both in vitro and in vivo. Knockdown of LINC00675 markedly suppressed tumor formation and attenuated enzalutamide resistance of PCa cells. Mechanistically, LINC00675 could directly modulate androgen receptor's (AR) interaction with mouse double minute-2 (MDM2) and block AR's ubiquitination by binding to it. Meanwhile, LINC00675 could bind to GATA2 mRNA and stabilize its expression level, in which GATA2 could act as a co-activator in the AR signaling pathway. Notably, we treated subcutaneous xenografts models with enzalutamide and antisense oligonucleotides (ASO) targeting LINC00675 in vivo and found that targeting LINC00675 would benefit androgen-deprivation-insensitive models. Our findings disclose that the LINC00675/MDM2/GATA2/AR signaling axis is a potential therapeutic target for CRPC patients.

Recent scenario of long non-coding RNAs as a diagnostic and prognostic biomarkers of prostate cancer

Prostate cancer (CaP) is a leading cause of cancer deaths in the worldwide with broad range of clinical manifestations ranging from relatively indolent to aggressive metastasis. Altered expression of many circulating long non-coding RNAs (lncRNAs), known to have role in tumorigenesis and metastasis, have already been reported in CaP patients. These lncRNAs modulate CaP pathogenesis by modulating multiple genes and thus altering metabolic pathways. Sustained androgen receptor (AR) signaling is one such key feature of castration-resistant prostate cancer, a CaP stage that has unmet need of accurate diagnostic and prognostic tools, that is affected by lncRNAs. In this review, we have discussed the emerging functions and associations of AR lncRNAs in CaP and highlighted their potential implications in cancer diagnostics and therapeutics. Further, extensive literature analysis in this article indicates that there is an immediate unmet need in the translational approach toward the hitherto identified AR lncRNAs. The characterization of AR lncRNAs involved in CaP is not exhaustive and adequate validation studies are still required to corroborate the present results that would be the impending future of basic research setting into clinical practice.

Coordinated AR and microRNA regulation in prostate cancer

The androgen receptor (AR) remains a key driver of prostate cancer (PCa) progression, even in the advanced castrate-resistant stage, where testicular androgens are absent. It is therefore of critical importance to understand the molecular mechanisms governing its activity and regulation during prostate tumourigenesis. MicroRNAs (miRs) are small ∼22 nt non-coding RNAs that regulate target gene, often through association with 3′ untranslated regions (3′UTRs) of transcripts. They display dysregulation during cancer progression, can function as oncogenes or tumour suppressors, and are increasingly recognised as targets or regulators of hormonal action. Thus, understanding factors which modulate miRs synthesis is essential. There is increasing evidence for complex and dynamic bi-directional cross-talk between the multi-step miR biogenesis cascade and the AR signalling axis in PCa. This review summarises the wealth of mechanisms by which miRs are regulated by AR, and conversely, how miRs impact AR's transcriptional activity, including that of AR splice variants. In addition, we assess the implications of the convergence of these pathways on the clinical employment of miRs as PCa biomarkers and therapeutic targets.

Epigenetic regulation of prostate cancer: the theories and the clinical implications

Epigenetics is the main mechanism that controls transcription of specific genes with no changes in the underlying DNA sequences. Epigenetic alterations lead to abnormal gene expression patterns that contribute to carcinogenesis and persist throughout disease progression. Because of the reversible nature, epigenetic modifications emerge as promising anticancer drug targets. Several compounds have been developed to reverse the aberrant activities of enzymes involved in epigenetic regulation, and some of them show encouraging results in both preclinical and clinical studies. In this article, we comprehensively review the up-to-date roles of epigenetics in the development and progression of prostate cancer. We especially focus on three epigenetic mechanisms: DNA methylation, histone modifications, and noncoding RNAs. We elaborate on current models/theories that explain the necessity of these epigenetic programs in driving the malignant phenotypes of prostate cancer cells. In particular, we elucidate how certain epigenetic regulators crosstalk with critical biological pathways, such as androgen receptor (AR) signaling, and how the cooperation dynamically controls cancer-oriented transcriptional profiles. Restoration of a "normal" epigenetic landscape holds promise as a cure for prostate cancer, so we concluded by highlighting particular epigenetic modifications as diagnostic and prognostic biomarkers or new therapeutic targets for treatment of the disease.

Long non-coding RNA FAM66C is associated with clinical progression and promotes cell proliferation by inhibiting proteasome pathway in prostate cancer

Prostate cancer is the most prevalent malignancy in men, and the identification of novel oncogenes is clinically valuable for early screening, prevention and treatment. Recently, the studies have revealed that long non-coding RNAs (lncRNAs) play important roles in the development and progression of cancers including prostate cancer. The present study aims to identify a novel lncRNA that correlated with the survival time of prostate cancer patients and try to explore its biological functions in prostate cancer cells. After analysing the prostate carcinoma dataset of the Cancer Genome Atlas (TCGA), the lncRNA FAM66C was screened with its expression highly correlated with patient survival time, tumour stage and Gleason pattern. Real-time PCR showed that FAM66C highly expressed in prostate cancer cells, and knockdown FAM66C by siRNAs resulted in significant inhibition of cell growth. Furthermore, the results indicated that FAM66C promoted cell growth due to increasing cell proliferation but not decreasing cell apoptosis. In addition, FAM66C activated the epidermal growth factor receptor (EGFR)-extracellular signal-regulated kinase (ERK) signalling to promote cell proliferation. The result of Western Blotting and lysosomal acidity detection showed that knockdown FAM66C increased the protein ubiquitination and the lysosomal acidity. Moreover, inhibition of proteasome pathway could increase the activation of EGFR-ERK signalling and cell proliferation. Taken together, these results suggested that lncRNA FAM66C activate EGFR-ERK signalling to promote cell proliferation by inhibiting proteasome pathway in prostate cancer. SIGNIFICANCE OF THE STUDY: We demonstrated that lncRNA FAM66C was associated with clinical progression. In addition, highly expressed lncRNA FAM66C in prostate cancer cell lines promoted cell proliferation. Moreover, lncRNA FAM66C activate the epidermal growth factor receptor (EGFR)-extracellular signal-regulated kinase (ERK) signalling to promote cell proliferation by inhibiting proteasome pathway in prostate cancer. This study might provide lncRNA FAM66C as a potential therapeutic target gene of prostate cancer.

Long Non-coding RNA SNHG17 Promotes Cell Proliferation and Invasion in Castration-Resistant Prostate Cancer by Targeting the miR-144/CD51 Axis

Previously, we found that the expression of long non-coding RNA (lncRNA) small nucleolar RNA host gene 17 (SNHG17) was up-regulated in castration-resistant prostate cancer (CRPC) cells compared to that in hormone sensitive prostate cancer (HSPC) cells. Moreover, we found that CD51 was up-regulated in prostate cancer cells and promoted the carcinogenesis and progression of prostate cancer. However, the regulatory mechanism of SNHG17 and CD51 in the development of CRPC remains unclear. In the current study, we aimed to elucidate the expressions, functions, and underlying mechanism of SNHG17 and CD51 in CRPC. Our results further confirmed that both SNHG17 and CD51 were up-regulated in CRPC tissues and cells. In addition, we found that SNHG17 expression was positively correlated with CD51 expression in prostate cancer. Mechanically, SNHG17 functioned as a competing endogenous RNA (ceRNA) to up-regulate CD51 expression through competitively sponging microRNA-144 (miR-144), and CD51 was identified as a direct downstream target of miR-144 in CRPC. Functionally, down-regulation of SNHG17 or up-regulation of miR-144 inhibited the proliferation, migration, and invasion of CRPC cells, whereas up-regulation of SNHG17 and down-regulation of miR-144 promoted the proliferation, migration and invasion of CRPC cells in vitro and in vivo. Using gain and loss-of function assay and rescue assay, we showed that miR-144 inhibited cell proliferation, migration and invasion by directly inhibiting CD51 expression, and SNHG17 promoted cell proliferation, migration and invasion by directly enhancing CD51 expression in CRPC cells. Taken together, our study reveals the role of the SNHG17/miR-144/CD51 axis in accelerating CRPC cell proliferation and invasion, and suggests that SNHG17 may serve as a novel therapeutic target for CRPC.

A feed-forward regulatory network lncPCAT1/miR-106a-5p/E2F5 regulates the osteogenic differentiation of periodontal ligament stem cells

Periodontal ligament stem cells (PDLSCs) are characterized by multiple differentiation potential and potent self-renewal ability, yet much remains to be elucidated that what determines these properties. Long noncoding RNAs (lncRNAs) have been suggested to involve in multiple biological process under physiological and pathological conditions, including osteogenic differentiation. In the present study, we performed comprehensive lncRNA profiling by lncRNA microarray analysis and identified prostate cancer-associated ncRNA transcript-1 (lncPCAT1) was gradually increased in PDLSCs during consecutive osteogenic induction, and it could further positively regulate the osteogenic differentiation both in vitro and in vivo, whereas lncPCAT1 inhibition led to suppressed osteogenic differentiation. Thereafter, we inferred a predicted interaction between lncPCAT1 and miR-106a-5p and then confirmed the direct binding sites of miR-106a-5p on lncPCAT1. Although miR-106a-5p upregulation led to decreased osteogenic differentiation, lncPCAT1 overexpression could reverse its suppression, indicating that lncPCAT1 act as a competing endogenous RNA for miR-106a-5p. Moreover, lncPCAT1 could sponge miR-106a-5p to upregulate miR-106a-5p-targeted gene BMP2, which was a crucial gene involved in osteogenic differentiation. Interestingly, we found that E2F5, another target of miR-106a-5p, could bind to the promoter of lncPCAT1 and then form a feed-forward regulatory network targeting BMP2. In conclusion, our study provided a novel lncRNA-miRNA feed-forward regulatory network and a promising target to modulate the osteogenic differentiation of PDLSCs.

The previously uncharacterized lncRNA APP promotes prostate cancer progression by acting as a competing endogenous RNA

Long noncoding RNAs (lncRNAs) promote cell proliferation, migration, invasion and castration resistance in prostate cancer (PCa). Understanding the inherited molecular mechanisms by which lncRNAs contribute to the progression of PCa to a lethal disease could have an important impact on cancer detection, diagnosis and prognosis. In our study, PCa-associated lncRNA transcripts from RNA-seq data were identified and screened via bioinformatics analysis, NCBI annotations and literature review. We identified a novel lncRNA, lncAPP (lncRNA activated in PCa progression), which activates in PCa progression and is expressed in primary tumor tissues and urine samples of patients with localized or advanced PCa. Urinary-based lncAPP is a promising biomarker for predicting PCa progression. In vitro and in vivo studies demonstrated that lncAPP enhanced cell proliferation and promoted migration and invasion. The underlying mechanism of lncRNA was investigated by RNA immunoprecipitation, dual-luciferase reporter system assay, etc. Upregulation of lncAPP promoted cell migration and invasion via competitively binding miR218 to facilitate ZEB2/CDH2 expression. In addition, in vivo subcutaneous tumor xenograft models and tail intravenously injection metastatic models were constructed to evaluate lncRNA function. Targeting lncAPP/miR218 axis in cell lines and tumor xenografts restrained tumor progression properties both in vitro and in vivo. These results establish that lncAPP/miR218 axis plays a critical role in PCa progression, and they also suggest new strategies to prevent tumor progression for therapeutic purposes.

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.

Interplay between the androgen receptor signaling axis and microRNAs in prostate cancer

The androgen receptor (AR) is a ligand-activated transcription factor that drives prostate cancer. Since therapies that target the AR are the mainstay treatment for men with metastatic disease, it is essential to understand the molecular mechanisms underlying oncogenic AR signaling in the prostate. miRNAs are small, non-coding regulators of gene expression that play a key role in prostate cancer and are increasingly recognized as targets or modulators of the AR signaling axis. In this review, we examine the regulation of AR signaling by miRNAs and vice versa and discuss how this interplay influences prostate cancer growth, metastasis and resistance to therapy. Finally, we explore the potential clinical applications of miRNAs implicated in the regulation of AR signaling in this prevalent hormone-driven disease.

Integrative analysis reveals driver long non-coding RNAs in osteosarcoma

Transcriptome profiling of osteosarcoma (OS) by next generation sequencing technology (NGS) has been broadly performed by previous researches, which uncovers a large number protein-coding driver genes, facilitates our understanding of the molecular mechanisms of OS formation, progression and metastasis. Recently, more and more researchers realize the importance of long non-coding RNAs (lncRNAs) on the development of OS. However, few studies focus on discovering driver lncRNAs.Here we collected somatic copy number alterations (SCNAs) and gene expression profiles of 84 samples from Therapeutically Applicable Research to Generate Effective Treatments (TARGET) project. The RNA sequencing data detected 13,903 expressed lncRNAs, 157 of which were previously reported to be associated with cancer based on the annotations from Lnc2Cancer database.By analyzing the SNP array data, several significant SCNAs were detected, such as the amplifications on chromosomes 1q, 4q, 17p, 17q, and 19q, and deletions on 1q, 3q, 9p, 10q, and 15q. With the SCNA and gene expression profiles, we identified 167 driver genes by integrative analysis, including 162 novel driver lncRNAs, 2 lncRNAs reported to be associated with OS, and another 3 associated with other cancers. Furthermore, functional characterization and survival analysis revealed that RP11-241F15.10 may function as a tumor suppressor in OS, and loss of function may contribute to activation of Wnt signaling pathway.This study not only facilitates our understanding of the oncogenic or tumor-suppressor role of lncRNAs in OS, but also provides potential therapies for the patients with OS with metastasis or relapse.

Long non-coding RNAs in prostate cancer: Biological and clinical implications

Prostate cancer (PCa) is a major health issue in the Western world. Current clinical imperatives for this disease include better stratification of indolent versus aggressive disease to enable improved patient management, as well as the identification of more effective therapies for the prevention and treatment of metastatic and therapy-resistant PCa. The advent of next-generation transcriptomics led to the identification of an important class of molecules, long non-coding RNAs (lncRNAs). LncRNAs have critical functions in normal physiology, but their dysregulation has also been implicated in the development and progression of a variety of cancers, including PCa. Importantly, a subset of lncRNAs are highly prostate-specific, suggesting potential for utility as both biomarkers and therapeutic targets. In this review, we summarise the biology of lncRNAs and their mechanisms of action in the development and progression of prostate cancer. Additionally, we cast a critical eye over the potential for this class of molecules to impact on clinical practice.

Overexpression of AR-regulated lncRNA TMPO-AS1 correlates with tumor progression and poor prognosis in prostate cancer

BACKGROUND

Prostate cancer (PCa) is a leading cause of death in males all over the world; besides, the diagnosis and therapy of it are still challenging. Researchers have revealed that long non-coding RNAs (lncRNAs) play important roles in the genesis and progression of human cancers, including PCa.

METHODS

Bioinformatics analysis and Kaplan-Meier survival analysis were utilized to confirm TMPO-AS1 as a diagnostic and prognostic marker. The TMPO-AS1 levels in both patient tissues and PCa cell lines were determined by qRT-PCR analysis. Moreover, the chromatin immunoprecipitation (ChIP) assay identified that TMPO-AS1 was a direct target of AR. The effect of overexpression or knockdown of TMPO-AS1 on cell proliferation, migration, cell cycle, and cell apoptosis was assessed by using CCK-8, transwell assays, and flow cytometric analysis, respectively.

RESULTS

Based on primary screening, we found that TMPO-AS1 could be a useful diagnostic and prognostic marker for PCa, whose expression was upregulated in PCa samples and associated with poorer prognosis. Bioinformatics predictions revealed TMPO-AS1 was associated with a series of biological processes involved in PCa progression. In PCa cells, TMPO-AS1 was predominantly localized in the cytoplasm and directly down-regulated by AR. Gain/loss-of-function assays showed TMPO-AS1 overexpression increased cell proliferation by promoting cell cycle progression and promoted migration, but reduced apoptosis of PCa cells. In addition, TMPO-AS1 may be a diagnostic and prognostic marker in multiple cancer types.

CONCLUSIONS

AR-regulated lncRNA TMPO-AS1 functioned as an oncogenic lncRNA in PCa, and may be a potential diagnostic and prognostic biomarker to be used as a therapeutic target for PCa.

PlncRNA-1 is overexpressed in retinoblastoma and regulates retinoblastoma cell proliferation and motility through modulating CBR3

PlncRNA-1 has been suggested to function as an oncogenic role in prostate cancer, colorectal cancer, hepatocellular carcinoma, esophageal squamous cell carcinoma, and gastric cancer. The expression pattern of PlncRNA-1 in retinoblastoma remained unknown. Therefore, the aim of this study was to explore the clinical significance of PlncRNA-1 in retinoblastoma patient and the biological function and molecular mechanism of PlncRNA-1 in regulating retinoblastoma cell proliferation, migration, and invasion. The results showed the level of PlncRNA-1 expression was obviously increased in retinoblastoma tissues and cell lines compared with compared with normal retina tissues and retina cell lines, respectively. Meanwhile, patients with advanced stage retinoblastoma had higher levels of PlncRNA-1 expression than patients with early stage retinoblastoma. There was an inverse correlation between PlncRNA-1 expression and CBR3 expression in retinoblastoma tissues, and PlncRNA-1 negatively regulated mRNA and protein expressions of CBR3. The in vitro experiments showed that down-regulation of PlncRNA-1 expression suppressed retinoblastoma cell proliferation, migration and invasion through up-regulating CBR3. In conclusion, PlncRNA-1 serves as an oncogenic lncRNA in regulating retinoblastoma cell proliferation, migration, and invasion through proliferation, migration, and invasion through up-regulating CBR3. © 2018 IUBMB Life, 70(10):969-975, 2018.

Construction of a microRNA‑associated feed‑forward loop network that identifies regulators of cardiac hypertrophy and acute myocardial infarction

Feed‑forward loops (FFLs) are three‑gene modules that exert significant effects on a series of biological processes and carcinogenesis development. MicroRNA‑associated FFLs (miR‑FFLs) represent a new era in disease research. However, analysis of the miR‑FFL network motifs has yet to be systematically performed, and their potential role in cardiac hypertrophy and acute myocardial infarction (AMI) requires investigation. The present study used a computational method to establish a comprehensive miR‑FFL network for cardiac hypertrophy and AMI, by integrating high‑throughput data from different sources and performing multi‑aspect analysis of the network features. Several heart disease‑associated miR‑FFL motifs were identified that were specific or common to the two diseases investigated. Functional analysis further revealed that miR‑FFL motifs provided specific drug targets for the clinical treatment of cardiac hypertrophy and AMI. Associations between specific drugs associated with heart disease and dysregulated FFLs were also identified. The present study highlighted the components of FFL motifs in cardiac hypertrophy and AMI, and revealed their possibility as heart disease biomarkers and novel treatment targets.

Emerging role of lncRNAs in the normal and diseased intestinal barrier

OBJECTIVE

A significant effort has been made to understand the intestinal barrier, but the effective means to prevent, reduce, and restore intestinal mucosal damage remains unclear. Recently, a few of studies have explained the mechanism of the intestinal barrier in long noncoding RNAs (lncRNAs). This review aims to summarize recent views on the function of lncRNAs in the intestinal barrier and discuss the emerging role of lncRNAs in intestinal barrier diseases caused by inflammatory diseases.

METHODS

Observations led us to believe that lncRNAs participate in inflammatory responses, cell proliferation, and control microbial susceptibility. In view of these, lncRNAs have been proved to involve in the intestinal barrier.

RESULTS

lncRNAs directly or indirectly affect TJ mRNA translation and intestinal epithelial cells (IECs) paracellular permeability, as well as IECs proliferation and susceptibility to apoptosis, to modulate the function of the intestinal barrier. miRNAs play a pivotal role in this process.

CONCLUSIONS

lncRNAs have been shown to be fundamentally involved in intestinal mucosal regeneration, protection, and epithelial barrier function. It may emerge as new and potential factors to be evaluated in the intestinal barrier diseases caused by acute pancreatitis, inflammatory bowel diseases, and imbalance of intestinal flora.

LncRNA CBR3-AS1 predicts unfavorable prognosis and promotes tumorigenesis in osteosarcoma

LncRNA CBR3-AS1 has been suggested to promote malignancy in several types of human cancers, but the clinical significance and biological function of lncRNA CBR3-AS1 in osteosarcoma is still unknown. The purpose of our study is to explore the clinical significance of lncRNA CBR3-AS1 in osteosarcoma patients and the biological function in osteosarcoma cells. In our results, we found lncRNA CBR3-AS1 was highly-expressed in osteosarcoma tissues and cell lines, and associated with Enneking stage, distant metastasis and histological grade. Survival analysis indicated that the high-expression of lncRNA CBR3-AS1 was an independent poor prognostic factor for osteosarcoma patients. Loss-of-function studies showed knockdown of lncRNA CBR3-AS1 suppressed osteosarcoma cells proliferation, migration and invasion, and promotes cells apoptosis, but had no effect on cell-cycle distribution. There was no association between lncRNA CBR3-AS1 and CBR3 expression in osteosarcoma tissues, and knockdown of lncRNA CBR3-AS1 had no effect on CBR3 mRNA and protein expression osteosarcoma cells. In conclusion, lncRNA CBR3-AS1 serves an oncogenic role to regulate osteosarcoma cells proliferation, migration, invasion and apoptosis, and is an independent poor prognostic factor for osteosarcoma patients.

Upregulation of long non-coding RNA PlncRNA-1 promotes proliferation and induces epithelial-mesenchymal transition in prostate cancer

Objective

To confirm that PlncRNA-1 regulates the cell cycle in prostate cancer cells and induces epithelial-mesenchymal transition (EMT) in prostate cancer through the TGF-β1 pathway.

Results

PlncRNA-1 and TGF-β1 expression levels were significantly higher in prostate cancer tissues than in normal prostate tissues (P < 0.05) and were significantly positively correlated. TGF-β1, N-cadherin and Cyclin-D1 were downregulated and E-Cadherin was upregulated in LNCAP cells after silencing of PlncRNA-1, as determined by real-time PCR and Western blot. TGF-β1, N-cadherin and Cyclin-D1 were upregulated and E-cadherin was downregulated in C4-2 cells, as determined by real-time PCR and Western blot. Overexpression of PlncRNA-1 in C4-2 cells was observed when TGF-β1 inhibitor LY2109761 was added. Western blot analysis showed that compared with their expression when TGF-β1 inhibitor LY2109761 was not added, N-Cadherin and CyclinD1 expression decreased and E-Cadherin expression increased. Transwell results showed that the invasive ability of C4-2 cells was enhanced after overexpression of PlncRNA-1, and the invasion ability was decreased after addition of TGF-β1 inhibitor LY2109761. The cell cycle was blocked by overexpression of PlncRNA-1 in C4-2 and by the addition of TGF-β1 inhibitor LY2109761, as determined by flow cytometry. In vitro experiments showed that PlncRNA-1 can regulate the growth of prostate cancer cells and EMT through the TGF-β1 pathway. In vivo experiments also confirmed the above results. Tumor growth was significantly blocked by overexpressing PlncRNA-1 in C4-2 cells and by the TGF-β1 inhibitor LY2109761 in animal experiments.

Materials and Methods

The expression levels of PlncRNA-1 and TGF-β1 were analyzed in 19 prostate cancer tissue samples and in adjacent normal tissue samples, 4 Pca cell lines, including LNCaP, C4-2, DU145, and PC3, and 1 normal prostate epithelial cell line RWPE-1. LNCAP cells were divided into the LNCAP control group and the LNCAP-PlncRNA-1-siRNA group. Cells from the prostate cancer cell line C4-2 were divided into the C4-2 control group and the C4-2-PlncRNA-1 experimental group. Changes in TGF-β1, E-cadherin and N-cadherin were detected by qPCR and Western Blot assay after silencing and overexpression of PlncRNA-1. The cell cycle, cell invasion, and levels of Cyclin-D1, E-Cadherin, and N-Cadherin were observed after adding TGF-β1 inhibitor LY2109761 in the C4-2-PlncRNA-1 group. The effects of TGF-β1 inhibitor LY2109761 on the tumorigenicity of C4-2 cells after overexpression of PlncRNA-1 was investigated in vivo.

Conclusions

PlncRNA-1 is an oncogene that regulates the cell cycle, cyclin-D1 and EMT in prostate cancer cells through the TGF-β1 pathway.

Carcinogenesis in prostate cancer: The role of long non-coding RNAs

LncRNAs appear to play a considerable role in tumourigenesis through regulating key processes in cancer cells such as proliferative signalling, replicative immortality, invasion and metastasis, evasion of growth suppressors, induction of angiogenesis and resistance to apoptosis. LncRNAs have been reported to play a role in prostate cancer, particularly in regulating the androgen receptor signalling pathway. In this review article, we summarise the role of 34 lncRNAs in prostate cancer with a particular focus on their role in the androgen receptor signalling pathway and the epithelial to mesenchymal transition pathway.

Construction of a lncRNA-mediated feed-forward loop network reveals global topological features and prognostic motifs in human cancers

Long non-coding RNAs (lncRNAs), transcription factors and microRNAs can form lncRNA-mediated feed-forward loops (L-FFLs), which are functional network motifs that regulate a wide range of biological processes, such as development and carcinogenesis. However, L-FFL network motifs have not been systematically identified, and their roles in human cancers are largely unknown. In this study, we computationally integrated data from multiple sources to construct a global L-FFL network for six types of human cancer and characterized the topological features of the network. Our approach revealed several dysregulated L-FFL motifs common across different cancers or specific to particular cancers. We also found that L-FFL motifs can take part in other types of regulatory networks, such as mRNA-mediated FFLs and ceRNA networks, and form the more complex networks in human cancers. In addition, survival analyses further indicated that L-FFL motifs could potentially serve as prognostic biomarkers. Collectively, this study elucidated the roles of L-FFL motifs in human cancers, which could be beneficial for understanding cancer pathogenesis and treatment.

Knockdown of lncRNA HNF1A-AS1 inhibits oncogenic phenotypes in colorectal carcinoma

Long non-coding RNAs (lncRNAs) have been demonstrated to serve important roles in the development and progression of cancer. Recently HNF1A antisense RNA 1 (HNF1A‑AS1), a lncRNA, has been reported as exhibiting a potential oncogenic role in the development of many types of cancer. However, the expression and the role of HNF1A‑AS1 in colorectal carcinoma (CRC) remains unclear. In the present study, the role of HNF1A‑AS1 in CRC was examined for the first time and its correlation with CRC cell biological behaviors was analyzed. The results demonstrated that HNF1A‑AS1 was distinctly upregulated in CRC tissues and associated with CRC metastasis to the lymph nodes. Reverse transcription‑quantitative polymerase chain reaction revealed that HNF1A‑AS1 was also upregulated in CRC cell lines and localized in the nucleus. In addition, knockdown of HNF1A‑AS1 expression notably inhibited CRC cell proliferation, migration, invasion and colony formation, and suppressed S‑phase entry in vitro. Taken together, these results suggested that HNF1A‑AS1 might serve as a promising prognostic marker for CRC tumorigenesis and progression.

An androgen reduced transcript of LncRNA GAS5 promoted prostate cancer proliferation

Prostate cancer (PCa) becomes a leading cause of death in males nowadays. Recent reports showed that androgen-responsive long non-coding RNAs played important roles in tumorigenesis and progression of PCa. In this study, we focused on a special transcript of GAS5 (ENST00000456293.5, GAS5-007), which was reported as a tumor suppressor. Here, we demonstrated GAS5-007 was reduced by androgen treatment and inhibited by AR. Next, we explored the expression level of GAS, finding the expression of it in PCa tissue was higher than normal tissue in both public databases and human tissue samples. Functional analysis of GAS5 showed it was related to regulating translational elongation, protein biosynthesis, and transcription. Moreover, we observed GAS5-007 knockdown inhibited the proliferation, cell cycle and promoted cell apoptosis of PCa. We also constructed a GAS5-miRNA network to explain the different roles of different GAS5 transcripts in PCa. This study provides novel insights to identify potential diagnostic biomarker and therapy target for prostate cancer in clinical treatment.