miR-515-5p controls cancer cell migration through MARK4 regulation

The implications for urological malignancies of non-coding RNAs in the the tumor microenvironment

Urological malignancies are a major global health issue because of their complexity and the wide range of ways they affect patients. There's a growing need for in-depth research into these cancers, especially at the molecular level. Recent studies have highlighted the importance of non-coding RNAs (ncRNAs) – these don't code for proteins but are crucial in controlling genes – and the tumor microenvironment (TME), which is no longer seen as just a background factor but as an active player in cancer progression. Understanding how ncRNAs and the TME interact is key for finding new ways to diagnose and predict outcomes in urological cancers, and for developing new treatments. This article reviews the basic features of ncRNAs and goes into detail about their various roles in the TME, focusing specifically on how different ncRNAs function and act in urological malignancies.

Progress in the development of Modulators targeting Frizzleds

The Frizzleds (FZDs) receptors on the cell surface belong to the class F of G protein-coupled receptors (GPCRs) which are the major receptors of WNT protein that mediates the classical WNT signaling pathway and other non-classical pathways. Besides, the FZDs also play a core role in tissue regeneration and tumor occurrence. With the structure and mechanism of FZDs activation becoming clearer, a series of FZDs modulators (inhibitors and agonists) have been developed, with the hope of bringing benefits to the treatment of cancer and degenerative diseases. Most of the FZDs inhibitors (small molecules, antibodies or designed protein inhibitors) block WNT signaling through binding to the cysteine-rich domain (CRD) of FZDs. Several small molecules impede FZDs activation by targeting to the third intracellular domain or the transmembrane domain of FZDs. However, three small molecules (FZM1.8, SAG1.3 and purmorphamine) activate the FZDs through direct interaction with the transmembrane domain. Another type of FZDs agonists are bivalent or tetravalent antibodies which activate the WNT signaling via inducing FZD-LRP5/6 heterodimerization. In this article, we reviewed the FZDs modulators reported in recent years, summarized the critical molecules' discovery processes and the elucidated relevant structural and pharmacological mechanisms. We believe the summaried molecular mechanisms of the relevant modulators could provide important guidance and reference for the future development of FZD modulators.

Design, synthesis, molecular docking and anti-proliferative activity of novel phenothiazine containing imidazo[1,2-a]pyridine derivatives against MARK4 protein

A series of novel phenothiazine-containing imidazo[1,2-a]pyridine derivatives were designed and synthesized under metal-free conditions in excellent yield. These derivatives were effectively transformed further into N-alkyl, sulfoxide, and sulfone derivatives. Derivatives were deployed against human microtubule affinity regulating kinase (MARK4), some molecules play crucial roles in cell-cycle progression such as G1/S transition and regulator of microtubule dynamics. Hence, molecules have shown excellent MARK4 inhibitory potential. Molecules with excellent IC50 values were selected for further studies such as ligand interactions using fluorescence quenching experiments for the binding constant. The highest binding constant was calculated as K = 0.79 × 105 and K = 0.1 × 107 for compounds 6a and 6h, respectively. Molecular docking, cell cytotoxicity, mitochondrial reactive oxygen species measurement and oxidative DNA damage were also studied to understand the mechanism of action of the molecules on cancer cells. It was found that the designed and synthesized compounds played anti-cancer roles by binding and inhibiting MARK4 protein.

Biomarker potential of competing endogenous RNA networks in Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is the most common condition affecting women of reproductive age globally. PCOS continues to be the largest contributing factor to female infertility despite significant progress in our knowledge of the molecular underpinnings and treatment of the condition. The fact that PCOS is a very diverse condition makes it one of the key reasons why we haven't been able to overcome it. Non-coding RNAs (ncRNAs) are implicated in the development of PCOS, according to growing evidence. However, it is unclear how the complex regulatory relationships between the many ncRNA types contribute to the growth of this malignancy. Competing endogenous RNA (ceRNA), a recently identified mechanism in the RNA world, suggests regulatory interactions between various RNAs, including long non-coding RNAs (lncRNAs), microRNAs (miRNAs), transcribed pseudogenes, and circular RNAs (circRNAs). Recent studies on PCOS have shown that dysregulation of multiple ceRNA networks (ceRNETs) between these ncRNAs plays crucial roles in developing the defining characteristics of PCOS development. And it is believed that such a finding may open a new door for a deeper comprehension of PCOS's unexplored facets. In addition, it may be able to provide fresh biomarkers and effective therapy targets for PCOS. This review will go over the body of information that exists about the primary roles of ceRNETs before highlighting the developing involvement of several newly found ceRNETs in a number of PCOS characteristics.

M2 macrophage-derived exosomal circTMCO3 acts through miR-515-5p and ITGA8 to enhance malignancy in ovarian cancer

Tumor-associated macrophages of the M2 phenotype promote cancer initiation and progression. Importantly, M2 macrophage-derived exosomes play key roles in the malignancy of cancer cells. Here, we report that circTMCO3 is upregulated in ovarian cancer patients, and its high expression indicates poor survival. M2-derived exosomes promote proliferation, migration, and invasion in ovarian cancer, but these effects are abolished by knockdown of circTMCO3. Furthermore, circTMCO3 functions as a competing endogenous RNA for miR-515-5p to reduce its abundance, thus upregulating ITGA8 in ovarian cancer. miR-515-5p inhibits ovarian cancer malignancy via directly downregulating ITGA8. The decreased oncogenic activity of circTMCO3-silencing exosomes is reversed by miR-515-5p knockdown or ITGA8 overexpression. Exosomal circTMCO3 promotes ovarian cancer progression in nude mice. Thus, M2 macrophage-derived exosomes promote malignancy by delivering circTMCO3 and targeting the miR-515-5p/ITGA8 axis in ovarian cancer. Our findings not only provide mechanistic insights into ovarian cancer progression, but also suggest potential therapeutic targets.

Harnessing memantine in Alzheimer's disease therapy through inhibition of microtubule affinity-regulating kinase: Mechanistic insights

Alzheimer's disease (AD) is one of the neurodegenerative disorder that primarily affects memory, thinking, and behavior, eventually leading to severe cognitive impairment. Therapeutic management of AD is urgently needed to improve the quality and lifestyle of patients. Tau phosphorylating kinases are considered attractive therapeutic targets. Microtubule affinity-regulating kinase 4 (MARK4) is directly linked with pathological phosphorylations of tau, highlighting its role in the therapeutic targeting of AD. The current manuscript shows the MARK4 inhibitory effect of Memantine (MEM), a drug used in treating AD. We have performed fluorescence based binding measurements, enzyme inhibition assay, docking and molecular dynamics (MD) simulations to understand the binding of of MARK4 and MEM and subsequent inhibition in the kinase activity. A 100 ns MD simulations provided a detailed analysis of MARK4-MEM complex and the role of potential critical residues in the binding. Finally, this study provides molecular insights into the therapeutic implication of MEM in AD therapeutics. We propose MEM effectively inhibits MARK4, it may be implicated in the development of targeted and efficient treatments for AD.

Therapeutic targeting of microtubule affinity-regulating kinase 4 in cancer and neurodegenerative diseases

Microtubule affinity-regulating kinase 4 (MARK4) is a member of the Ser/Thr protein kinase family, phosphorylates the microtubule-connected proteins and plays a vital role in causing cancers and neurodegenerative diseases. This kinase modulates multiple signaling pathways, including mammalian target of rapamycin, nuclear factor-κB, and Hippo-signaling, presumably responsible for cancer and Alzheimer's. MARK4 acts as a negative controller of the Hippo-kinase cassette for promoting YAP/TAZ action, and the loss of MARK4 detains the tumorigenic properties of cancer cells. MARK4 is involved in tau hyperphosphorylation that consequently affects neurodegeneration. MARK4 is a promising drug target for cancer, diabetes, and Alzheimer's. Developing the potent and selective inhibitors of MAKR4 are promising in the therapeutic management of associated diseases. Despite its great significance, a few reviews are available to discuss its structure, function and clinical significance. In the current review, we aimed to provide detailed information on the structural features of MARK4 targeted in drug development and its role in various signaling pathways related to cancer and neurodegenerative diseases. We further described the therapeutic potential of MARK4 inhibitors in preventing numerous diseases. Finally, the updated information on MARK4 will be helpful in the further development of effective therapeutic molecules.

Circ-UBR4 regulates the proliferation, migration, inflammation, and apoptosis in ox-LDL-induced vascular smooth muscle cells via miR-515-5p/IGF2 axis

The aim of our study is to disclose the role and underlying molecular mechanisms of circular RNA ubiquitin protein ligase E3 component n-recognin 4 (circ-UBR4) in atherosclerosis (AS). Our data showed that circ-UBR4 expression was upregulated in AS patients and oxidized low-density lipoprotein (ox-LDL)-induced vascular smooth muscle cells (VSMCs) compared with healthy volunteer and untreated VSMCs. In addition, ox-LDL stimulated proliferation, migration, and inflammation but decreased apoptosis in VSMCs, which were overturned by the inhibition of circ-UBR4. miR-515-5p was sponged by circ-UBR4, and its inhibitor reversed the inhibitory effect of circ-UBR4 knockdown on proliferation, migration, and inflammation in ox-LDL-induced VSMCs. Insulin-like growth factor2 (IGF2) was a functional target of miR-515-5p, and overexpression of IGF2 reversed the suppressive effect of miR-515-5p on ox-LDL-stimulated VSMCs proliferation, migration, and inflammation. Collectively, circ-UBR4 knockdown decreased proliferation, migration, and inflammation but stimulated apoptosis in ox-LDL-induced VSMCs by targeting the miR-515-5p/IGF2 axis.

ABERRANT EXPRESSION OF COL14A1, CELRS3, and CTHRC1 IN BREAST CANCER СELLS

BACKGROUND

Collagens, which are the major components of the extracellular matrix involved in the regulation of tumor microenvironment, could be differentially expressed in breast cancer (BC) with different transcriptome profiling.

AIM

To analyze the transcript level expression of COL1A1, COL5A1, COL10A1, COL11A1, COL12A1, COL14A1, CTHRC1, and CELRS3 genes and the clinical relevance of their differential expression in BC.

MATERIALS AND METHODS

The transcript level expression of the genes was analyzed using the quantitative real-time PCR (qPCR) in tumor tissue of 60 BC patients.

RESULTS

Overexpression of COL1A1, COL5A1, COL10A1, COL11A1, COL12A1, CTHRC, and CELRS3 anddown-regulated expression of COL14A1 were observed. COL14A1 down-regulation was associated with aggressive, basal, and Her-2/neu BC subtypes (p = 0.031). Overexpression of CELSR3 was found to be associated with the older age of the patients (> 55 years, p = 0.049). Further analysis with the TCGA BC data set has shown a concordance in the differential expression of the above genes. Furthermore, overexpression of CTHRC1 was associated with poor overall survival (OS), particularly with poor prognosis (p = 0.00042) for the luminal BC subtype. On the other hand, CELSR3 overexpression was associated with mucinous tumors and poor prognosis in post-menopausal women. In silicotarget prediction identified several BC-associated miRNAs and members of miR-154, -515, and -10 families to perform a likely regulatory role in the above ECM genes.

CONCLUSION

The present study shows that the expression of COL14A1 and CTHRC1 may serve as potential biological markers for the detection of basal BC and the prognosis of survival for patients with the luminal subtype of BC.

LKB1 Signaling and Patient Survival Outcomes in Hepatocellular Carcinoma

The liver is a major organ that is involved in essential biological functions such as digestion, nutrient storage, and detoxification. Furthermore, it is one of the most metabolically active organs with active roles in regulating carbohydrate, protein, and lipid metabolism. Hepatocellular carcinoma is a cancer of the liver that is associated in settings of chronic inflammation such as viral hepatitis, repeated toxin exposure, and fatty liver disease. Furthermore, liver cancer is the most common cause of death associated with cirrhosis and is the 3^rd leading cause of global cancer deaths. LKB1 signaling has been demonstrated to play a role in regulating cellular metabolism under normal and nutrient deficient conditions. Furthermore, LKB1 signaling has been found to be involved in many cancers with most reports identifying LKB1 to have a tumor suppressive role. In this review, we use the KMPlotter database to correlate RNA levels of LKB1 signaling genes and hepatocellular carcinoma patient survival outcomes with the hopes of identifying potential biomarkers clinical usage. Based on our results STRADß, CAB39L, AMPKα, MARK2, SIK1, SIK2, BRSK1, BRSK2, and SNRK expression has a statistically significant impact on patient survival.

Nitroimidazoles Part 10. Synthesis, crystal structure, molecular docking, and anticancer evaluation of 4-nitroimidazole derivatives combined with piperazine moiety

Piperazine-tagged imidazole derivatives 3a (symmetrical di-substituted piperazine) and 5-11 were synthesized through the combination of 4-nitroimidazole derivatives with piperazine moiety. The structural characterization was done by different physical and spectral techniques like NMR (¹H and ¹³C) and mass spectrometry. The constituency of compound 3a was confirmed by X-ray structural analyses. All compounds were assessed for their antiproliferative inhibition potency against five human cancer cell lines namely MCF-7, PC3, MDA-231, A549 and Fibro dental. Compound 5 was found to be the most potent anticancer agents against MCF-7 cell line with IC₅₀ values of (1.0 ± 0 µm) and against PC3 with IC₅₀ value of (9.00 ± 0.028 µm). The molecular docking of compound 5 had been studied, and the results revealed that the newly designed 4-nitroimidazole combined with piperazine moiety derivatives bond to the hydrophobic pocket and polar contacts with high affinity.

Inhibition of microtubule affinity regulating kinase 4 by an acetylcholinesterase inhibitor, Huperzine A: Computational and experimental approaches

Microtubule affinity regulating kinase 4 (MARK4), 752 amino acids long, belonging to the AMPK superfamily, plays a vital role in regulating microtubules due to its potential to phosphorylate microtubule-associated proteins (MAP's) and thus, MARK4 plays a key role in Alzheimer's disease (AD) pathology. MARK4 is a druggable target for cancer, neurodegenerative diseases, and metabolic disorders. In this study, we have evaluated the MARK4 inhibitory potential of Huperzine A (HpA), an acetylcholinesterase inhibitor (AChEI), a potential AD drug. Molecular docking revealed the key residues governing the MARK4-HpA complex formation. The structural stability and conformational dynamics of the MARK4-HpA complex was assessed by employing Molecular dynamics (MD) simulation. The results suggested that the binding of HpA with MARK4 leads to minimal structural alterations in the native conformation of MARK4, implying the stability of the MARK4-HpA complex. Isothermal titration calorimetry (ITC) studies deciphered that HpA binds to MARK4 spontaneously. Moreover, the kinase assay depicted significant inhibition of MARK by HpA (IC₅₀ = 4.91 μM), implying it to be a potent MARK4 inhibitor that can be implicated in the treatment of MARK4-directed diseases.

miR-515-5p suppresses trophoblast cell invasion and proliferation through XIAP regulation in preeclampsia

MicroRNAs (miRNAs) are non-coding small RNA molecules that can be secreted into the circulation and which exist in remarkably stable forms. Circulating miRNAs regulate numerous biological process and are aberrantly expressed in pathological conditions. Differentially expressed circulating miRNAs have received attention as potential biomarkers for many diseases. In this study, we revealed that miR-515-5p was significantly upregulated in maternal serum from preeclampsia patients in comparison to normal pregnant women. Bioinformatics prediction and a dual-luciferase reporter gene assay revealed that miR-515-5p directly targets the X-linked inhibitor of apoptosis protein (XIAP) 3'-untranslated region. In addition, the overexpression of miR-515-5p inhibited the proliferation and invasion of HTR-8/SVneo trophoblast cells. The decreased XIAP expression and reduced epithelial-mesenchymal transition (EMT) were observed in the preeclamptic placenta. Collectively, miR-515-5p may play critical roles in the pathogenesis of preeclampsia through suppression of XIAP, and serum miR-515-5p may act as a potential biomarker for preeclampsia.

circSMARCA5 Is an Upstream Regulator of the Expression of miR-126-3p, miR-515-5p, and Their mRNA Targets, Insulin-like Growth Factor Binding Protein 2 (IGFBP2) and NRAS Proto-Oncogene, GTPase (NRAS) in Glioblastoma

The involvement of non-coding RNAs (ncRNAs) in glioblastoma multiforme (GBM) pathogenesis and progression has been ascertained but their cross-talk within GBM cells remains elusive. We previously demonstrated the role of circSMARCA5 as a tumor suppressor (TS) in GBM. In this paper, we explore the involvement of circSMARCA5 in the control of microRNA (miRNA) expression in GBM. By using TaqMan^® low-density arrays, the expression of 748 miRNAs was assayed in U87MG overexpressing circSMARCA5. Differentially expressed (DE) miRNAs were validated through single TaqMan^® assays in: (i) U87MG overexpressing circSMARCA5; (ii) four additional GBM cell lines (A172; CAS-1; SNB-19; U251MG); (iii) thirty-eight GBM biopsies; (iv) twenty biopsies of unaffected brain parenchyma (UC). Validated targets of DE miRNAs were selected from the databases TarBase and miRTarbase, and the literature; their expression was inferred from the GBM TCGA dataset. Expression was assayed in U87MG overexpressing circSMARCA5, GBM cell lines, and biopsies through real-time PCR. TS miRNAs 126-3p and 515-5p were upregulated following circSMARCA5 overexpression in U87MG and their expression was positively correlated with that of circSMARCA5 (r-values = 0.49 and 0.50, p-values = 9 × 10^-5 and 7 × 10^-5, respectively) in GBM biopsies. Among targets, IGFBP2 (target of miR-126-3p) and NRAS (target of miR-515-5p) mRNAs were positively correlated (r-value = 0.46, p-value = 0.00027), while their expression was negatively correlated with that of circSMARCA5 (r-values = -0.58 and -0.30, p-values = 0 and 0.019, respectively), miR-126-3p (r-value = -0.36, p-value = 0.0066), and miR-515-5p (r-value = -0.34, p-value = 0.010), respectively. Our data identified a new GBM subnetwork controlled by circSMARCA5, which regulates downstream miRNAs 126-3p and 515-5p, and their mRNA targets IGFBP2 and NRAS.

MRCKα is a novel regulator of prolactin-induced lactogenesis in bovine mammary epithelial cells

Myotonic dystrophy-related Cdc42-binding kinase alpha (MRCKα) is an integral component of signaling pathways controlling vital cellular processes, including cytoskeletal reorganization, cell proliferation and cell survival. In this study, we investigated the physiological role of MRCKα in milk protein and fat production in dairy cows, which requires a dynamic and strict organization of the cytoskeletal network in bovine mammary epithelial cells (BMEC). Within a selection of 9 Holstein cows, we found that both mRNA and protein expression of MRCKα in the mammary gland were upregulated during lactation and correlated positively (r > 0.89) with the mRNA and protein levels of β-casein. Similar positive correlations (r > 0.79) were found in a primary culture of BMEC stimulated with prolactin for 24 h. In these cells, silencing of MRCKα decreased basal β-casein, sterol-regulatory element binding protein (SREBP)-1 and cyclin D1 protein level, phosphorylation of mTOR, triglyceride secretion, cell number and viability-while overexpression of MRCKα displayed the reversed effect. Notably, silencing of MRCKα completely prevented the stimulatory action of prolactin on the same parameters. These data demonstrate that MRCKα is a critical mediator of prolactin-induced lactogenesis via stimulation of the mTOR/SREBP1/cyclin D1 signaling pathway.

Microtubule-affinity regulating kinase 4: A potential drug target for cancer therapy

The human genome encodes more than 500 protein kinases that work by transferring the γ-phosphate group from ATP to serine, threonine, or tyrosine (Ser/Thr/Tyr) residues. Various kinases are associated with the onset of cancer and its further progression. The recent advancements in developing small-molecule kinase inhibitors to treat different cancer types have shown noticeable results in clinical therapies. Microtubule-affinity regulating kinase 4 (MARK-4) is a Ser/Thr protein kinase that relates structurally to AMPK/Snf1 subfamily of the CaMK kinases. The protein kinase modulates major signalling pathways such as NF-κB, mTOR and the Hippo-signalling pathway. MARK4 is associated with various cancer types due to its important role in regulating microtubule dynamics and subsequent cell division. Aberrant expression of MARK4 is linked with several pathologies such as cancer, Alzheimer's disease, obesity, etc. This review provides detailed information on structural aspects of MARK4 and its role in various signalling pathways related to cancer. Several therapeutic molecules were designed to inhibit the MARK4 activity from controlling associated diseases. The review further highlights kinase-targeted drug discovery and development in oncology and cancer therapies. Finally, we summarize the latest findings regarding the role of MARK4 in cancer, diabetes, and neurodegenerative disease path to provide a solid rationale for future investigation and therapeutic intervention.

MARK2 regulates chemotherapeutic responses through class IIa HDAC-YAP axis in pancreatic cancer

Despite paclitaxel's wide use in cancer treatment, patient response rate is still low and drug resistance is a major clinical obstacle. Through a Phos-tag-based kinome-wide screen, we identified MARK2 as a critical regulator for paclitaxel chemosensitivity in PDAC. We show that MARK2 is phosphorylated by CDK1 in response to antitubulin chemotherapeutics and in unperturbed mitosis. Phosphorylation is essential for MARK2 in regulating mitotic progression and paclitaxel cytotoxicity in PDAC cells. Mechanistically, our findings also suggest that MARK2 controls paclitaxel chemosensitivity by regulating class IIa HDACs. MARK2 directly phosphorylates HDAC4 specifically during antitubulin treatment. Phosphorylated HDAC4 promotes YAP activation and controls expression of YAP target genes induced by paclitaxel. Importantly, combination of HDAC inhibition and paclitaxel overcomes chemoresistance in organoid culture and preclinical PDAC animal models. The expression levels of MARK2, HDACs, and YAP are upregulated and positively correlated in PDAC patients. Inhibition of MARK2 or class IIa HDACs potentiates paclitaxel cytotoxicity by inducing mitotic abnormalities in PDAC cells. Together, our findings identify the MARK2-HDAC axis as a druggable target for overcoming chemoresistance in PDAC.

Kinase Activity of PAR1b, Which Mediates Nuclear Translocation of the BRCA1 Tumor Suppressor, Is Potentiated by Nucleic Acid-Mediated PAR1b Multimerization

PAR1b is a cytoplasmic serine/threonine kinase that controls cell polarity and cell-cell interaction by regulating microtubule stability while mediating cytoplasmic-to-nuclear translocation of BRCA1. PAR1b is also a cellular target of the CagA protein of Helicobacter pylori, which leads to chronic infection causatively associated with the development of gastric cancer. The CagA-PAR1b interaction inactivates the kinase activity of PAR1b and thereby dampens PAR1b-mediated BRCA1 phosphorylation, which reduces the level of nuclear BRCA1 and thereby leads to BRCAness and BRCAness-associated genome instability underlying gastric carcinogenesis. While PAR1b can multimerize within the cells, little is known about the mechanism and functional role of PAR1b multimerization. We found in the present study that PAR1b was multimerized in vitro by binding with nucleic acids (both single- and double-stranded DNA/RNA) via the spacer region in a manner independent of nucleic-acid sequences, which markedly potentiated the kinase activity of PAR1b. Consistent with these in vitro observations, cytoplasmic introduction of double-stranded DNA or expression of single-stranded RNA increased the PAR1b kinase activity in the cells. These findings indicate that the cytoplasmic DNA/RNA contribute to nuclear accumulation of BRCA1 by constitutively activating/potentiating cytoplasmic PAR1b kinase activity, which is subverted in gastric epithelial cells upon delivery of H. pylori CagA oncoprotein.

LncRNA ubiquitin-binding protein domain protein 10 antisense RNA 1 inhibits colon adenocarcinoma progression via the miR-515-5p/slit guidance ligand 3 axis

Dysregulated long non-coding RNAs (lncRNAs) play an important role in cancer progression. However, there have been limited reports to date of the involvement of ubiquitin-binding protein domain protein 10 antisense RNA 1 (UBXN10-AS1) in cancer. Our aim was to explore the role and underlying mechanism of UBXN10-AS1 in the occurrence of colon adenocarcinoma (COAD). Real-time quantitative PCR and Western blotting were performed to determine the expression of UBXN10-AS1, miR-515-5p, and Slit guidance ligand 3 (SLIT3). Cell Counting Kit-8 and wound healing scratch assays were performed to measure COAD cell proliferation and migration. A xenograft assay was performed to examine tumor growth in vivo. Luciferase reporter and RNA immunoprecipitation (RIP) assays were used to determine the binding interaction among miR-515-5p, UBXN10-AS1, and SLIT3. The results showed that UBXN10-AS1 and SLIT3 were expressed at low levels in COAD tissues, while miR-515-5p was expressed at high levels. UBXN10-AS1 overexpression suppressed tumor growth in vitro and in vivo. The luciferase reporter and RNA RIP assays demonstrated that UBXN10-AS1 targeted miR-515-5p, which in turn targeted SLIT3. Functionally, miR-515-5p overexpression reversed the inhibition of COAD cell proliferation and migration by UBXN10-AS1 overexpression, and SLIT3 overexpression counteracted the oncogenicity of miR-515-5p. Our study shows that UBXN10-AS1 modulates the miR-515-5p/SLIT3 axis, thereby resulting in the inhibition of COAD cell proliferation and migration.

Inhibition of MARK4 by serotonin is an attractive therapeutic approach to combat Alzheimer’s disease and neuroinflammation

The mitogen-activated protein kinases (MAPKs) govern various cellular programs and crucial intermediate pathways in signaling. Microtubule affinity-regulating kinase 4 (MARK4) is a part of the kinase family recognized for actively...

Regulation of transforming growth factor-beta1 by circANKS1B/miR-515-5p affects the metastatic potential and cisplatin resistance in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the most common oral cancer, with an increasing worldwide incidence and a worsening prognosis. Emerging evidence confirms that circular RNAs (circRNAs) play a critical role in tumor progression via sponging miRNAs. A previous study substantiated the function of circANKS1B in several cancers. However, its role in OSCC remains unclear. This study revealed the high expression of circANKS1B in OSCC tissues and cells. Moreover, the expression level of circANKS1B was highly positively correlated with the expression of transforming growth factor-beta1 (TGF-β1) in OSCC tissues. Additionally, overexpression of circANKS1B enhanced the protein expression of TGF-β1 in OSCC cells, while its inhibition reduced TGF-β1 protein levels. Noticeably, the loss-function of circANKS1B restrained OSCC cell invasion, migration, and epithelial to mesenchymal transition (EMT) by decreasing N-cadherin expression and enhancing E-cadherin expression. Furthermore, the knockdown of circANKS1B sensitized OSCC cells to cisplatin by suppressing cell viability and increasing cell apoptosis and caspase-3 activity. Mechanically, bioinformation software (circinteractome and starBase 3.0) and dual-luciferase reporter assays corroborated that circANKS1B could sponge miR-515-5p. Moreover, miR-515-5p could directly target TGF-β1 to suppress its expression. Importantly, inhibition of miR-515-5p or supplementation with TGF-β1 overturned the effects of circANKS1B knockdown on cell invasion, migration, and cisplatin resistance. Thus, these findings highlight that circANKS1B might act as an oncogenic gene to facilitate the metastatic potential and cisplatin resistance in OSCC by sponging miR-515-5p to regulate TGF-β1. Collectively, circANKS1B may be a promising target for therapy and overcoming chemoresistance in OSCC.

Circular RNA circPIP5K1A contributes to cancer stemness of osteosarcoma by miR-515-5p/YAP axis

Background

Osteosarcoma is a common type of bone tumors and frequently occurs in children and adolescents. Cancer stem cells (CSCs) are a unique sub-type of self-renewal cancer cells and the stemness of cancer cells are involved in the spread, recurrence, metastasis, and even therapeutic resistance. However, the regulation mechanisms of CSCs in osteosarcoma are poorly understood. Circular RNA (circRNA) is a unique sort of non-coding RNAs and widely participate in the modulation of cancer progression.

Methods

In this study, we identified the critical function of circular RNA circPIP5K1A in stemness of osteosarcoma cells.

Results

CircPIP5K1A expression was significantly enhanced in clinical osteosarcoma tissues compared with the adjacent normal tissues. The depletion of circPIP5K1A by siRNA repressed osteosarcoma cell viabilities and induced osteosarcoma cell apoptosis. The suppression of circPIP5K1A attenuated the capabilities of invasion and migration of osteosarcoma cells. The circPIP5K1A knockdown increased E-Cadherin expression and decreased Vimentin expression in osteosarcoma cells. The sphere formation abilities of osteosarcoma cells were repressed by the depletion of circPIP5K1A. The CD133⁺CD44⁺ cell population of osteosarcoma cells was reduced by circPIP5K1A knockdown. The expression of ALDH1 and Nanog was decreased by the inhibition of circPIP5K1A in osteosarcoma cells. Mechanically, circPIP5K1A enhanced YAP expression by targeting miR-515-5p. MiR-515-5p inhibited stemness of osteosarcoma cells. The CSCs properties of osteosarcoma cells were repressed by circPIP5K1A knockdown or miR-515-5p mimic, while miR-515-5p inhibitor or YAP overexpression reversed circPIP5K1A knockdown-induced repression. Tumor xenograft analysis in nude mice demonstrated that the depletion of circPIP5K1A represses osteosarcoma cell growth in vivo.

Conclusion

In conclusion, we identified that circular RNA circPIP5K1A contributed to cancer stemness of osteosarcoma by miR-515-5p/YAP axis. Targeting circPIP5K1A may be considered as a potential therapeutic strategy for osteosarcoma treatment.

Myricetin inhibits breast and lung cancer cells proliferation via inhibiting MARK4

Identifying novel molecules as potential kinase inhibitors are gaining significant attention globally. The present study suggests Myricetin as a potential inhibitor of microtubule-affinity regulating kinase (MARK4), adding another molecule to the existing list of anticancer therapeutics. MARK4 regulates initial cell division steps and is a potent druggable target for various cancers. Structure-based docking with 100 ns molecular dynamics simulation depicted activity of Myricetin in the active site pocket of MARK4 and the formation of a stable complex. The fluorescence-based assay showed excellent affinity of Myricetin to MARK4 guided by static and dynamic quenching. Moreover, the assessment of enthalpy change (∆H) and entropy change (∆S) delineated electrostatic interactions as a dominant force in the MARK4-myricetin interaction. Isothermal titration calorimetric measurements revealed spontaneous binding of Myricetin with MARK4. Further, the kinase assay depicted significant inhibition of MARK4 by Myricetin with IC₅₀  = 3.11 µM. Additionally, cell proliferation studies established that Myricetin significantly inhibited the cancer cells (MCF-7 and A549) proliferation, and inducing apoptosis. This study provides a solid rationale for developing Myricetin as a promising anticancer molecule in the MARK4 mediated malignancies.

Circular RNA hsa_circ_0103552 Promotes Proliferation, Migration, and Invasion of Breast Cancer Cells through Upregulating Cysteine-Rich Angiogenic Inducer 61 (CYR61) Expression via Sponging MicroRNA-515-5p

Circular RNAs (circRNAs) exert a significant regulatory function on tumor progression. This work intends to probe into the biological function and regulatory mechanism of circRNA_0103552 (circ_0103552) in breast cancer carcinogenesis. In this study, circ_0103552, microRNA-515-5p (miR-515-5p), and cysteine-rich angiogenic inducer 61 (CYR61) mRNA expressions in breast cancer cells and tissues were determined by quantitative real-time polymerase chain reaction, followed by cell counting kit 8 and Transwell experiments to examine the multiplication, migration, and invasion of breast cancer cells. Circular RNA Interactome database and StarBase database were searched, and dual-luciferase reporter gene experiments were applied to verify the targeting relationship between circ_0103552 and miR-515-5p, and between miR-515-5p and CYR61, and Western blot was adopted to the regulatory function of circ_0103552 and miR-515-5p on CYR61 protein expression. Circ_0103552 expression was found to be remarkably up-modulated in breast cancer tissues and cells, and circ_0103552 overexpression facilitated the multiplication, migration, and invasion of breast cancer cells, while knocking down circ_0103552 induced the opposite effects. Mechanistically, circ_0103552 could sponge miR-515-5p and restrained its expression in breast cancer cells. MiR-515-5p could counteract the functions of circ_0103552 in breast cancer cells. Additionally, CYR61 was revealed to be a downstream target of miR-515-5p in breast cancer cells. In summary, this study shows that circ_0103552 up-modulates CYR61 expression by targeting miR-515-5p and thus facilitates the multiplication, migration, and invasion of breast cancer cells.

miR-515-5p inhibits the proliferation, migration and invasion of human breast cancer cells by targeting CBX4

microRNA (miR)-515-5p has been previously suggested to function as a tumor suppressor in various types of human cancer. Therefore, the role of miR-515-5p in breast cancer (BC) was explored in the present study. A series of assays were performed to study the function of miR-515-p in BC cells, including Cell Counting Kit-8, TUNEL, flow cytometric and colony formation to detect cell viability and apoptosis, wound healing and Transwell assays to measure cell motility. In addition, reverse transcription quantitative PCR and western blot analysis were used to assess miR-515-5p, CBX4, Cox-2, MMP2, MMP9, CDK2, p21 and Cyclin D1 respectively. Bioinformatics and dual-luciferase reporter assays were used to analyze the target genes of miR-515-5p, which confirmed the direct binding between miR-515-5p and polycomb chromobox 4 (CBX4). It was found that the expression of miR-515-5p is lower in BC cells compared with that in normal breast cells (MCF10A). Overexpression of miR-515-5p using the miR-515 mimic was found to reduce cell viability, facilitate cell apoptosis, inhibit cell proliferation and arrest cell cycle progressio at G₁ phase. In addition, miR-515-5p overexpression could inhibit cell migration and invasion, whilst decreasing the expression levels of prostaglandin-endoperoxide synthase 2, MMP2 and MMP9 proteins. In addition, miR-515-5p overexpression could reduce the expression levels of CBX4 in MCF7 and ZR-75-30 cells. By contrast, overexpression of CBX4 reversed the effects of the miR-515-5p mimic transfection on cell proliferation, migration and invasion in MCF7 and ZR-75-30 cells. In combination, these results suggest that miR-515-5p inhibits BC cell proliferation, migration and invasion by directly targeting CBX4.

Non-Coding RNA and Frizzled Receptors in Cancer

Frizzled receptors have been long recognized for their role in Wnt/β-catenin signaling, a pathway known for its tumorigenic effects. More recent studies of frizzled receptors include efforts to understand non-coding RNA (ncRNA) regulation of these receptors in cancer. It has become increasingly clear that ncRNA molecules are important for regulating the expression of both oncogenic and tumor-suppressive proteins. The three most commonly described ncRNA molecules are microRNAs (miRNAs), long non-coding RNAs (lncRNAs), and circular RNAs (circRNAs). Here, we review ncRNA molecules that directly or indirectly affect frizzled protein expression and downstream signaling. Exploring these interactions highlights the potential of incorporating ncRNA molecules into cancer prevention and therapy strategies that target frizzled receptors. Previous investigations of frizzled receptors and ncRNA have established strong promise for a role in cancer progression, but additional studies are needed to provide the substantial pre-clinical evidence required to translate findings to clinical applications.

LncRNA DLGAP1-AS1 accelerates glioblastoma cell proliferation through targeting miR-515-5p/ROCK1/NFE2L1 axis and activating Wnt signaling pathway

INTRODUCTION

Glioblastoma (GBM), the primary malignant tumor in the central nervous system, features high aggressiveness and mortality. Long noncoding RNAs (lncRNAs) can exert the crucial function in regulating various human diseases, including GBM. However, the function and mechanism of lncRNA DLGAP1 antisense RNA 1 (DLGAP1-AS1) in GBM remain still unknown.

METHODS

DLGAP1-AS1 expression in GBM cells was detected by RT-qPCR. Functional assays were conducted to determine GBM cell proliferation and apoptosis. RIP, RNA pull down, and luciferase reporter assay were applied for measuring the interplay of DLGAP1-AS1 with other RNAs.

RESULTS

DLGAP1-AS1 was distinctly upregulated in GBM cells. DLGAP1-AS1 depletion inhibited cell proliferation, but induced apoptosis. MiR-515-5p could be sponged by DLGAP1-AS1 in GBM cells and to repress cell proliferation in GBM. Further, Rho-associated coiled-coil containing protein kinase 1 (ROCK1) and Nuclear factor erythroid-2 like 1 (NFE2L1) were confirmed as the target gene of miR-515-5p. Wnt signaling pathway could be activated by DLGAP1-AS1 via regulating ROCK1 and NFE2L1 expression. Rescue assays proved that overexpression of both ROCK1 and NFE2L1 could totally reverse the inhibitory effect of silencing DLGAP1-AS1 on GBM cell proliferation.

CONCLUSION

LncRNA DLGAP1-AS1 accelerated cell proliferation in GBM via targeting miR-515-5p/ROCK1/NFE2L1 axis and activating Wnt signaling pathway.

Inhibition of the lncRNA Coded within Transglutaminase 2 Gene Impacts Several Relevant Networks in MCF-7 Breast Cancer Cells

Long non-coding RNAs are nucleotide molecules that regulate transcription in numerous cellular processes and are related to the occurrence of many diseases, including cancer. In this regard, we recently discovered a polyadenylated long non-coding RNA (named TG2-lncRNA) encoded within the first intron of the Transglutaminase type 2 gene (TGM2), which is related to tumour proliferation in human cancer cell lines. To better characterize this new biological player, we investigated the effects of its suppression in MCF-7 breast cancer cells, using siRNA treatment and RNA-sequencing. In this way, we found modifications in several networks associated to biological functions relevant for tumorigenesis (apoptosis, chronic inflammation, angiogenesis, immunomodulation, cell mobility, and epithelial–mesenchymal transition) that were originally attributed only to Transglutaminase type 2 protein but that could be regulated also by TG2-lncRNA. Moreover, our experiments strongly suggest the ability of TG2-lncRNA to directly interact with important transcription factors, such as RXRα and TP53, paving the way for several regulatory loops that can potentially influence the phenotypic behaviour of MCF-7 cells. These considerations imply the need to further investigate the relative relevance of the TG2 protein itself and/or other gene products as key regulators in the organization of breast cancer program.

Involvement of ferroptosis in the granulosa cells proliferation of PCOS through the circRHBG/miR-515/SLC7A11 axis

BACKGROUND

Polycystic ovary syndrome (PCOS) is the most common endocrine disease among women, but its etiology remains unknown. In recent years, many circular RNAs (circRNAs) have been confirmed to be related to the development of PCOS. The role and mechanism of circRNA in the development of PCOS need to be further explored.

METHODS

In the present study, we used the circRNA chip to detect the difference in the expression of circRNA in the granulosa cells of PCOS patients and controls. Five upregulated circRNAs were then selected for quantitative reverse transcription polymerase chain reaction (qRT-PCR) verification, and circRHBG was found to be upregulated in PCOS. Subsequently, Cell Counting Kit-8 assay and EdU assay were used to observe the effect of circRHBG on the proliferation of KGN and SVOG cells. Furthermore, the pairwise binding relationship between circRHBG/miR515-5 and miR515-5p/SLC7A11 was verified by luciferase reporter assay. The interaction between circRHBG and SLC7A11 was detected with qRT-PCR and Western blot.

RESULTS

CircRNA high-throughput chips and qRT-PCR verified that circRHBG was significantly upregulated in granular cells of PCOS patients. Knockdown of circRHBG inhibits KGN and SVOG cell proliferation. Luciferase reporter assays and Ago2-RIP detection showed that circRHBG competes with SLC7A11 to bind to miR-515-5p. Subsequent experiments verified knockdown of circRHBG promotes ferroptosis in PCOS.

CONCLUSIONS

circRHBG inhibits ferroptosis in PCOS cells through the circRHBG/miR-515-5p/SLC7A11 axis in PCOS, which may provide new diagnostic molecular markers and therapeutic targets for PCOS.

Silencing of circTASP1 inhibits proliferation and induces apoptosis of acute myeloid leukaemia cells through modulating miR-515-5p/HMGA2 axis

Acute myeloid leukaemia (AML) is a common hematopoietic disease that is harmful to the lives of children and adults. CircRNAs are aberrantly expressed in the haematologic malignancy cells. However, the expression of circTASP1 and its function in AML remain unclear. In this study, we showed that circTASP1 was significantly up‐regulated in AML peripheral blood samples and cells. Knockdown of circTASP1 inhibited proliferation and promoted apoptosis of HL60 and THP‐1 cells in vitro. Bioinformatics prediction and luciferase reporter assay proved that circTASP1 sponged miR‐515‐5p and negatively regulated miR‐515‐5p expression in HL60 and THP‐1 cells. High mobility group A2 (HMGA2) was proved to be a downstream target of miR‐515‐5p. The rescue experiments confirmed that knockdown of circTASP1 inhibited proliferation and induced apoptosis by modulating miR‐515‐5p/HMGA2 pathway. Moreover, the in vivo experiment indicated that knockdown of circTASP1 suppressed tumour growth. In conclusion, circTASP1 acts as a sponge for miR‐515‐5p to regulate HMGA2, thereby promoting proliferation and inhibiting apoptosis during AML progression. Thus, circTASP1 has the potential to be explored as a therapeutic target for AML treatment.

Mechanism of Ampelopsin Inhibiting Proliferation, Remove and Incursion of Colorectal Cancer Through Regulating the Expression of LncRNA ZFPM2-AS1/miR-515-5p

The incidence rate, recurrence and metastasis rate and mortality of colorectal cancer (CRC) are high. Therefore, clinical has been looking for better treatment. Ampelopsin (AMP) has obvious inhibitory effect on some tumors. However, there is no report on the effect and mechanism of AMP on rectal cancer. To investigate the effect and mechanism of AMP on the proliferation, migration and invasion of colorectal cancer cells, at first, different concentrations of Ampelopsis japonica group (10μM, 25 μM, 50 μM), control group (without AMP), pcDNA group, pcDNA-ZFPM2-AS1 group, si-NC group, si-ZFPM2-AS1 group, miR-NC group, miR-515-5p group, AMP+pcDNA group, AMP + pcDNA-ZFPM2-AS1 group were set up. Then the expression levels of miR-515-5p and ZFPM2-AS1 were detected by QRT-PCR, protein expression was detected by Western blot, cell proliferation inhibition rate was detected by MTT method, cell invasion and migration were detected by Transwell and fluorescence activity was detected by double luciferase reporter gene assay. The results show that compared with the control group, the proliferation inhibition rate of SW480 cells in different concentrations of AMP increased and the number of migration and invasion decreased significantly. Moreover, the expression levels of CyclinD1, MMP-2 and MMP-9 were significantly lower than those in the control group, while the expression of p21 was significantly increased. The expression level of miR-515-5pin SW480 cells treated with AMP was significantly increased, while the expression level of ZFPM2-AS1 was significantly decreased. Inhibition of ZFPM2-AS1 expression or miR-515-5p overexpression could inhibit the proliferation, migration and invasion of SW480 cells and then ZFPM2-AS1 overexpression reversed the inhibitory effect of AMP on the proliferation, migration and invasion of SW480 cells. Therefore, AMP affects the proliferation, migration and invasion of colorectal cancer cells by regulating the expression of lncRNA ZFPM2-AS1/miR-515-5p, which provides a new target and new idea for the prevention and treatment of colorectal cancer.

Long non-coding RNA DLGAP1-AS1 promotes the progression of gastric cancer via miR-515-5p/MARK4 axis

Long non-coding RNA (lncRNA) is an essential regulator of carcinogenesis and cancer progression. In the study, we explored the role of lncRNA DLGAP1-AS1 in gastric cancer (GC). qRT-PCR was carried out to detect DLGAP1-AS1 expression in GC tissues and cell lines. CCK-8 assay, EdU assay, and transwell experiments were employed to detect the malignant biological behaviors of GC cells with DLGAP1-AS1 knockdown or overexpression. Bioinformatics and dual-luciferase report assay were used to confirm the binding relationship between DLGAP1-AS1 and miR-515-5p. MARK4 expression was detected by western blot after DLGAP1-AS1/miR-515-5p was selectively regulated. DLGAP1-AS1 was up-regulated in GC tissues and cell lines, and its high expression was closely associated with larger tumor size, higher TNM stage, and lymph node metastasis. Furthermore, DLGAP1-AS1 overexpression enhanced cell proliferation, migration, and invasion, and miR-515-5p could reverse these effects. DLGAP1-AS1 participated in the regulation of the MARK4 signaling pathway by targeting miR-515-5p. DLGAP1-AS1 promoted GC progression through miR-515-5p/MARK4 signaling pathway.

ZFPM2-AS1 transcriptionally mediated by STAT1 regulates thyroid cancer cell growth, migration and invasion via miR-515-5p/TUSC3

Objective: Our purpose was to study the roles and molecular mechanisms of long non-coding RNA (lncRNA) ZFPM2 Antisense RNA 1 (ZFPM2-AS1) in thyroid cancer.

Methods: Firstly, the expression of ZFPM2-AS1, miR-515-5p and TUSC3 was detected in thyroid cancer tissues and cells. Secondary, their biological functions (proliferation, apoptosis, migration and invasion) were analyzed by a serious of functional experiments including cell counting kit-8 (CCK-8), clone formation, 5-Ethynyl-2'-deoxyuridine (EdU), enzyme-linked immunosorbent assay (ELISA), wound healing and Transwell assays. Thirdly, the mechanisms of STAT1/ZFPM2-AS1 and ZFPM2-AS1/miR-515-5p/TUSC were validated using chromatin immunoprecipitation (CHIP), pull-down and luciferase reporter assays.

Results: ZFPM2-AS1 and TUSC were both highly expressed and miR-515-5p was down-regulated in thyroid cancer tissues as well as cells. Their knockdown weakened thyroid cancer cell growth, migration, and invasion. ZFPM2-AS1 was mainly distributed in the nucleus and cytoplasm of thyroid cancer cells. Mechanistically, up-regulation of ZFPM2-AS1 was induced by transcription factor STAT1 in line with CHIP and luciferase reporter assays. Furthermore, as a sponge of miR-515-5p, ZFPM2-AS1 decreased the ability of miR-515-5p to inhibit TUSC3 expression by pull-down, luciferase reporter and gain-and-loss assays, thereby promoting malignant progression of thyroid cancer.

Conclusion: ZFPM2-AS1 acted as an oncogene in thyroid cancer, which was transcriptionally mediated by STAT1. Furthermore, ZFPM2-AS1 weakened the inhibitory effect of miR-515-5p on TUSC3. Thus, ZFPM2-AS1 could be an underlying biomarker for thyroid cancer.

Circ_0134111 knockdown relieves IL-1β-induced apoptosis, inflammation and extracellular matrix degradation in human chondrocytes through the circ_0134111-miR-515-5p-SOCS1 network

BACKGROUND

Osteoarthritis (OA) is characterized by chondrocyte injury and dysfunction, such as excessive apoptosis, inflammatory response and extracellular matrix (ECM) degradation. Circular RNA (circRNA) deregulation is reported to be involved in OA. Our study aimed to explore the role of circ_0134111 in OA.

METHODS

Human chondrocytes were treated with interleukin-1β (IL-1β) to mimic OA cell model. The expression of circ_0134111, miR-515-5p and suppressor of cytokine signaling 1 (SOCS1) mRNA was measured by real-time quantitative polymerase chain reaction (RT-qPCR), and the protein levels of SOCS1 and apoptosis-/inflammation-/ECM-related markers were determined by western blot. Cell proliferation and cell apoptosis were assessed using cell counting kit-8 (CCK-8) and flow cytometry assay, respectively. For mechanism analysis, the predicted interaction between miR-515-5p and circ_0134111 or SOCS1 was verified by dual-luciferase reporter assay, pull-down assay and RNA immunoprecipitation (RIP) assay. Rescue experiments were performed to explore the interplay between miR-515-5p and circ_0134111 or SOCS1.

RESULTS

Circ_0134111 was overexpressed in OA cartilage tissues and IL-1β-induced chondrocytes. IL-1β-induced chondrocyte apoptosis, inflammatory responses and ECM degradation were alleviated by circ_0134111 knockdown or miR-515-5p restoration. Circ_0134111 acted as miR-515-5p sponge to regulate miR-515-5p expression, and miR-515-5p deficiency reversed the effects of circ_0134111 knockdown in IL-1β-induced chondrocytes. MiR-515-5p directly bound to SOCS1, and circ_0134111 decoyed miR-515-5p to increase SOCS1 level. MiR-515-5p restoration alleviated IL-1β-induced chondrocyte apoptosis, inflammatory responses and ECM degradation, While SOCS1 overexpression partly abolished these effects.

CONCLUSION

Circ_0134111 knockdown alleviated apoptosis, inflammatory responses and ECM degradation in OA cell model by mediating the miR-515-5p-SOCS1 network, hinting that circ_0134111 was involved in OA progression.

CircNRIP1 Modulates the miR-515-5p/IL-25 Axis to Control 5-Fu and Cisplatin Resistance in Nasopharyngeal Carcinoma

Background

The development of drug resistance leads many NPC patients to experience disease relapse following the completion of chemotherapy. It is thus essential that the mechanistic basis for such chemoresistance be clarified in an effort to identify approaches to sensitizing NPC tumors to treatment with cisplatin and related agents.

Methods

A qRT-PCR approach was used to measure the expression of circNRIP1 in NPC, while luciferase assays were used to identify interactions with downstream targets of circNRIP1 activity including miR-515-5p and IL-25. CCK8 assays were also utilized to detect IC50 values for cisplatin and 5-Fu.

Results

The expression of circNRIP1 was significantly increased in the serum of chemoresistant NPC patients. At a functional level, we determined that circNRIP1 is able to sequester miR-515-5p, thereby inhibiting its ability to post-transcriptionally suppress IL-25 expression. We observed a significant negative correlation between the expression of miR-515-5p and circNRIP1 in serum samples from chemoresistant NPC patients, consistent with a functional interaction between these two factors. We further found that 5-Fu and CDDP IC50 values in NPC cells in which circNRIP1 had been knocked down were restored following miR-515-5p inhibitor transfection. Similarly, changes in these IC50 values were reversed in NPC cells transfected with miR-515-5p mimics following the overexpression of IL-25 in these same cells.

Conclusion

These data highlight the circNRIP1/miR-515-5p/IL-25 as a novel regulator of 5-Fu and cisplatin resistance in NPC, suggesting that this pathway may be amenable to therapeutic targeting as an approach to treating this cancer type.

Long Noncoding RNA ZFPM2-AS1 Knockdown Restrains the Development of Retinoblastoma by Modulating the MicroRNA-515/HOXA1/Wnt/β-Catenin Axis

Purpose

The tumor-initiating function of long non-coding RNA (lncRNA), zinc finger protein multitype 2 antisense RNA 1 (ZFPM2-AS1) was reported in lung cancer, yet the relevance of ZFPM2-AS1 in retinoblastoma (RB), a malignancy representing 2.5% to 4% incidence of cancers among children, has not been elucidated. Thus, we attempted to assess the effect of ZFPM2-AS1 and underlying mechanism in RB progression.

Methods

First, comparing the differentially expressed lncRNAs in normal retinal tissues as well as RB tissues, the target lncRNA ZFPM2-AS1 was screened out. We then assayed the ZFPM2-AS1 expression in three RB cell lines, and carried out methylthiazol tetrazolium (MTT), transwell assays, and flow cytometric analyses to examine the role of si-ZFPM2-AS1 on cell behaviors. Following online database predication, the correlations between ZFPM2-AS1 and microR-515 (miR-515) or homeobox A1 (HOXA1) were corroborated by dual-luciferase reporter gene assays. Quantitative real-time PCR along with Western blot assays was fulfilled to ascertain the expression of relevant genes.

Results

ZFPM2-AS1 was significantly overexpressed in RB tissues and cell lines, and ZFPM2-AS1 silencing curtailed the growth and metastasis of RB cells both in vitro and in vivo. Bioinformatic websites and dual-luciferase reporter gene assays disclosed that ZFPM2-AS1 might perform as a competing endogenous RNA for miR-515 and positively correlate with HOXA1 to activate the Wnt/β-catenin signaling pathway.

Conclusions

Altogether, these data demonstrated that ZFPM2-AS1 interacted with HOXA1 to promote RB development via mediating miR-515, establishing a promising therapeutic biomarker for RB and prognosis.

LncRNA SNHG3 Promotes Proliferation and Metastasis of Non-Small-Cell Lung Cancer Cells Through miR-515-5p/SUMO2 Axis

Lung cancer is a global disease and a major cause of cancer-related mortality worldwide. Accumulated studies have confirmed the essential role of long non-coding RNAs (lncRNAs) in the occurrence and development of cancers. Meanwhile, there have been reports concerning the role of Small Nucleolar RNA Host Gene 3 (SNHG3) in various cancers. However, there are so far few studies on the function and mechanism of SNHG3 in lung cancer. In the present study, SNHG3 was found to be highly expressed in lung cancer tissues and cells. Downregulation of SNHG3 could inhibit cell proliferation, migration, invasion and epithelial-mesenchymal transition (EMT) process. In addition, SNHG3 was found to have the ability to bind to miR-515-5p. Furthermore, Small Ubiquitin Like Modifier 2 (SUMO2) was identified to be the downstream target of miR-515-5p, which was negatively correlated with miR-515-5p expression. SNHG3 could positively regulate SUMO2 expression by sponging miR-515-5p. In addition, the rescue experiment showed that simultaneous transfection of miR-515-5p or SUMO2 siRNA could reverse the effect of SNHG3 expression on cell proliferation and metastasis. Collectively, our study demonstrates that SNHG3 can act on miR-515-5p in the form of competitive endogenous RNA (ceRNA) to regulate SUMO2 positively and thus affect the proliferation and metastasis of NSCLC cells. Findings in our study support that SNHG3/miR-515-5p/SUMO2 regulatory axis may become a potential therapeutic target for lung cancer.

Long Noncoding RNA MALAT1 Knockdown Inhibits Proliferation, Migration, and Invasion and Promotes Apoptosis in Non-Small-Cell Lung Cancer Cells Through Regulating miR-515-3p/TRIM65 Axis

Background: Long noncoding RNAs (lncRNAs) and mRNAs (messenger RNAs) have been reported to exert function in non-small-cell lung cancer (NSCLC), but how lncRNAs and mRNAs operate in the regulation of NSCLC is unclear. The purpose of this research was to elucidate the functional mechanism of lncRNA metastasis associated in lung adenocarcinoma transcript 1 (MALAT1) and tripartite-motif protein family member 65 (TRIM65) in NSCLC. Materials and Methods: Quantitative real-time polymerase chain reaction and western blot assay were employed to measure gene expression. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry analysis were performed to assess cell proliferation and apoptosis, respectively. Also, cell migratory and invasive abilities were detected by transwell assay. The interaction between miR-515-5p and MALAT1 or TRIM65 was predicted by starBase and then confirmed with the dual luciferase reporter assay, RNA immunoprecipitation (RIP) assay, or pull-down assay. Besides, mouse xenograft was conducted to analyze the effect of MALAT1 knockdown on tumor growth in vivo. Results: MALAT1 and TRIM65 expression was upregulated, and miR-515-5p expression was downregulated in NSCLC tissues and cells. Both MALAT1 knockdown and TRIM65 depletion suppressed cell proliferation, migration, and invasion and induced apoptosis in NSCLC cells. Interestingly, MALAT1 directly inhibited miR-515-5p expression and miR-515-5p decreased TRIM65 level through interaction. MALAT1 knockdown repressed NSCLC cell growth via modulation of miR-515-5p/TRIM65 axis. Furthermore, silencing MALAT1 inhibited tumor growth in vivo. Conclusions: Our findings demonstrated that MALAT1 depletion inhibited the growth of NSCLC cells by regulating miR-515-5p/TRIM65 axis, providing the theoretical basis for the therapy of NSCLC.

Targeted-regulating of miR-515-5p by LncRNA LOXL1-AS1 on the proliferation and migration of trophoblast cells

OBJECTIVE

This study aims to elucidate the molecular mechanism of LOXL1-AS1 in proliferation and migration of trophoblast cells.

METHODS

We have used specific small interfering RNAs (si-RNA) and microRNA (mi-RNA) to knock down the target gene or m-RNA. In this regard we used following siRNAs: si-NC, si-LOXL1-AS1, pcDNA-NC, pcDNA-LOXL1-AS1, miR-NC, miR-515-5p. These si-RNA and miRNA were transfected into JeG-3 cells. Real-time quantitative PCR (RT-qPCR) was used to detect the expressions of LOXL1-AS1 and miR-515-5p. Western blot was used to detect Cyclin D1, matrix metalloproteinase 2 (MMP2), matrix metalloproteinases 9 (MMP9), phosphorylated p65 (p-p65), profilin of phosphorylated nuclear transcription factor κB (p-IκBα). MTT assay was used to detect cell survival rate, and the luciferase assay was used to detected the targeting relationship of LOXL1-AS1 and miR-515-5p.

RESULTS

Our results showed that human placental trophoblast cells had higher level of LOXL1-AS1 in comparison to human choriocarcinoma cells, however, human placental trophoblast cells had lower level of miR-515-5p. In addition, the expression of CyclinD1, MMP2, MMP9 were significantly decreased in JeG-3 cell lines. We observed lower cell survival rate and lower cell migration number in JeG-3 cell lines. Our results demonstrated that LOXL1-AS1 could target miR-515-5p, and subsequently reverse the inhibitory effect of LOXL1-AS1 on proliferation and migration in JEG-3 cells. Also, lower expressions of p-p65 and p-IкBα in JeG-3 cells showed that miR-515-5p could reversed the inhibitory effect of LOXL1-AS1 on NF-κB signaling pathway.

CONCLUSIONS

The low expression of LOXL1-AS1 inhibits the proliferation and migration of human choriocarcinoma cells, which might be related to miR-515-5p and NF-κB signaling pathways.

Identification of miR-515-3p and its targets, vimentin and MMP3, as a key regulatory mechanism in esophageal cancer metastasis: functional and clinical significance

Metastasis is the main factor of treatment failure in cancer patients, but the underlying mechanism remains to be elucidated and effective new treatment strategies are urgently needed. This study aims to explore novel key metastasis-related microRNAs (miRNAs) in esophageal squamous cell carcinoma (ESCC). By comparing miRNA profiles of the highly metastatic ESCC cell sublines, we established through serial in vivo selection with the parental cells, we found that the expression level of miR-515-3p was lower in ESCC tumor tissues than adjacent normal tissues, further decreased in metastatic tumors, and moreover, markedly associated with advanced stage, metastasis and patient survival. The in vitro and in vivo assays suggested that miR-515-3p could increase the expression of the epithelial markers as well as decrease the expression of the mesenchymal markers, and more importantly, suppress invasion and metastasis of ESCC cells. Mechanistically, we revealed that miR-515-3p directly regulated vimentin and matrix metalloproteinase-3 (MMP3) expression by binding to the coding sequence and 3'untranslated region, respectively. In addition, the data from whole-genome methylation sequencing and methylation-specific PCR indicated that the CpG island within miR-515-3p promoter was markedly hypermethylated in ESCC cell lines and ESCC tumor tissues, which may lead to deregulation of miR-515-3p expression in ESCC. Furthermore, our preclinical experiment provides solid evidence that systemic delivery of miR-515-3p oligonucleotide obviously suppressed the metastasis of ESCC cells in nude mice. Taken together, this study demonstrates that miR-515-3p suppresses tumor metastasis and thus represents a promising prognostic biomarker and therapeutic strategy in ESCC.

Circ_0057553/miR-515-5p Regulates Prostate Cancer Cell Proliferation, Apoptosis, Migration, Invasion and Aerobic Glycolysis by Targeting YES1

Background

Prostate cancer (PCa) is one of the most common malignant cancer in males worldwide. Circular RNAs (CircRNAs) are novel type of non-coding RNAs. Recently, circRNAs have been reported participating in various cancers, including prostate cancer. However, the function and mechanism of circ_0057553 remain to be elucidated.

Methods and Materials

The RNA expression levels of circ_0057553, miR-515-5p, YES proto-oncogene 1 (YES1) and glycolytic genes mRNA were detected by qRT-PCR in PCa tissues or cells. Western blotting was performed to analyze YES1 protein level. Cell viability, migration and invasion and cell apoptosis were assessed by cell counting kit-8 (CCK-8) assay, transwell assay and flow cytometry. In addition, the effects of cell glycolysis were evaluated by measuring lactate production, glucose consumption and adenosine triphosphate (ATP) level. Moreover, dual-luciferase reporter assay was used to detect the target sites of circ_0057553 and miR-515-5p, miR-515-5p and YES1. RNA immunoprecipitation (RIP) was conducted to evaluate the target relationship between circ_0057553 and miR-515-5p. Xenograft mouse model was conducted to measure tumor formation in vivo.

Results

Circ_0057553 was significantly up-regulated in PCa tissues and cells. Knockdown of circ_0057553 inhibited cell viability, migration, invasion and glycolysis and facilitated apoptosis in PCa cells. Furthermore, circ_0057553 bound to miR-515-5p and miR-515-5p directly targeted YES1. Interestingly, miR-515-5p inhibitor partially rescued the function of circ_0057553 knockdown, while YES1 restored the effects of miR-515-5p overexpression. Circ_0057553 down-regulation remarkably decreased tumor volume and weight in vivo.

Conclusion

Circ_0057553 affected PCa cell viability, migration, invasion, apoptosis and glycolysis through miR-515-5p/YES1 axis.

Identification and genomic analysis of pedigrees with exceptional longevity identifies candidate rare variants

BACKGROUND

Longevity as a phenotype entails living longer than average and typically includes living without chronic age-related diseases. Recently, several common genetic components to longevity have been identified. This study aims to identify additional genetic variants associated with longevity using unique and powerful analyses of pedigrees with a statistical excess of healthy elderly individuals identified in the Utah Population Database (UPDB).

METHODS

From an existing biorepository of Utah pedigrees, six independent cousin pairs were selected from four extended pedigrees that exhibited an excess of healthy elderly individuals; whole exome sequencing (WES) was performed on two elderly individuals from each pedigree who were either first cousins or first cousins once removed. Rare (<.01 population frequency) variants shared by at least one elderly cousin pair in a region likely to be identical by descent were identified as candidates. Ingenuity Variant Analysis was used to prioritize putative causal variants based on quality control, frequency, and gain or loss of function. The variant frequency was compared in healthy cohorts and in an Alzheimer's disease cohort. Remaining variants were filtered based on their presence in genes reported to have an effect on the aging process, aging of cells, or the longevity process. Validation of these candidate variants included tests of segregation on other elderly relatives.

RESULTS

Fifteen rare candidate genetic variants spanning 17 genes shared within cousins were identified as having passed prioritization criteria. Of those variants, six were present in genes that are known or predicted to affect the aging process: rs78408340 (PAM), rs112892337 (ZFAT), rs61737629 (ESPL1), rs141903485 (CEBPE), rs144369314 (UTP4), and rs61753103 (NUP88 and RABEP1). ESPL1 rs61737629 and CEBPE rs141903485 show additional evidence of segregation with longevity in expanded pedigree analyses (p-values = .001 and .0001, respectively).

DISCUSSION

This unique pedigree analysis efficiently identified several novel rare candidate variants that may affect the aging process and added support to seven genes that likely contribute to longevity. Further analyses showed evidence for segregation for two rare variants, ESPL1 rs61737629 and CEBPE rs141903485, in the original longevity pedigrees in which they were initially observed. These candidate genes and variants warrant further investigation.

A Novel Circular RNA, circ_0005394, Predicts Unfavorable Prognosis and Contributes to Hepatocellular Carcinoma Progression by Regulating miR-507/E2F3 and miR-515-5p/CXCL6 Signaling Pathways

Objective

Circular RNAs (circRNAs) play a key role in cancer development and progression. Previously, circ_0005394 was found to be highly expressed in hepatocellular carcinoma (HCC) screened by circRNA microarray. However, the research with regard to the functions and mechanisms of circ_0005394 in HCC remains unknown.

Materials and Methods

The expression of circ_0005394 in HCC was measured by qRT-PCR. The clinical relevance was evaluated by Fisher's exact test, Kaplan-Meier curves, and Cox regression model. Gain/loss-of function assays were performed to elucidate the functions of circ_0005394 in Huh-7 and HepG2 cells. Dual-luciferase reporter assay was applied to reveal the mechanism of circ_0005394.

Results

circ_0005394 expression was higher in HCC tissues and cells than noncancerous samples and normal cell line, respectively. High expression of circ_0005394 was associated with larger tumor size, more advanced TNM stages, and poorer overall survival for the patients with HCC. Gain/loss-of function assays demonstrated its oncogenic role in cell growth, apoptosis, migration, and invasion. Mechanistically, miR-507 and miR-515-5p could be sponged by circ_0005394. Furthermore, E2F Transcription Factor 3 (E2F3) and C-X-C motif chemokine ligand 6 (CXCL6) were confirmed as the target of miR-507 and miR-515-5p, respectively. Rescue assay indicated that circ_0005394 facilitated HCC growth and invasion by regulating miR-507/E2F3 and miR-515-5p/CXCL6 signaling pathways.

Conclusion

This study uncovered an important role of circ_0005394 in regulating HCC progression, providing a novel perspective for clarifying its pathogenesis.

LncRNA SNHG3 promotes bladder cancer proliferation and metastasis through miR-515-5p/GINS2 axis

Growing evidence suggests that long non‐coding RNAs (lncRNAs) are associated with carcinogenesis. LncRNA small nucleolar RNA host gene 3 (SNHG3) is up‐regulated in various cancers and positively associated with poor prognosis of these cancers. However, the precise role of lncRNA SNHG3 in bladder cancer (Bca) remains unclear. In our research, we first reported that lncRNA SNHG3 was up‐regulated in bladder cancer tissues and positively related to poor clinical prognosis. Moreover, knockdown of lncRNA SNHG3 significantly suppressed the proliferation, migration, invasion and EMT process of Bca cells in vitro and vivo. Mechanistically, we revealed that suppression of SNHG3 evidently enhanced miR‐515‐5p expression and decreased GINS2 expression at posttranscriptional levels. Moreover, SNHG3 positively regulated GINS2 expression by sponging miR‐515‐5p under a competing endogenous RNA (ceRNA) mechanism. To sum up, our study suggested lncRNA SNHG3 acted as a microRNA sponge and an oncogenic role in the progression of bladder cancer.

Rosmarinic Acid Exhibits Anticancer Effects via MARK4 Inhibition

Microtubule affinity regulating kinase (MARK4) is a potential drug target for different types of cancer as it controls the early step of cell division. In this study, we have screened a series of natural compounds and finally identified rosmarinic acid (RA) as a potential inhibitor of MARK4. Molecular docking and 500 ns all-atom simulation studies suggested that RA binds to the active site pocket of MARK4, forming enough number of non-covalent interactions with critical residues and MARK4-RA complex is stable throughout the simulation trajectory. RA shows an excellent binding affinity to the MARK4 with a binding constant (K) of 107 M-1. Furthermore, RA significantly inhibits MARK4 activity (IC50 = 6.204 µM). The evaluation of enthalpy change (∆H) and entropy change (∆S) suggested that the MARK4-RA complex formation is driven by hydrogen bonding and thus complexation process is seemingly specific. The consequence of MARK4 inhibition by RA was further evaluated by cell-based tau-phosphorylation studies, which suggested that RA inhibited the phosphorylation of tau. The treatment of cancer cells with RA significantly controls cell growth and subsequently induces apoptosis. Our study provides a rationale for the therapeutic evaluation of RA and RA-based inhibitors in MARK4 associated cancers and other diseases.

MARK4 Inhibited by AChE Inhibitors, Donepezil and Rivastigmine Tartrate: Insights into Alzheimer's Disease Therapy

Microtubule affinity-regulating kinase (MARK4) plays a key role in Alzheimer’s disease (AD) development as its overexpression is directly linked to increased tau phosphorylation. MARK4 is a potential drug target of AD and is thus its structural features are employed in the development of new therapeutic molecules. Donepezil (DP) and rivastigmine tartrate (RT) are acetylcholinesterase (AChE) inhibitors and are used to treat symptomatic patients of mild to moderate AD. In keeping with the therapeutic implications of DP and RT in AD, we performed binding studies of these drugs with the MARK4. Both DP and RT bound to MARK4 with a binding constant (K) of 10⁷ M⁻¹. The temperature dependency of binding parameters revealed MARK−DP complex to be guided by static mode while MARK−RT complex to be guided by both static and dynamic quenching. Both drugs inhibited MARK4 with IC₅₀ values of 5.3 μM (DP) and 6.74 μM (RT). The evaluation of associated enthalpy change (ΔH) and entropy change (ΔS) implied the complex formation to be driven by hydrogen bonding making it seemingly strong and specific. Isothermal titration calorimetry further advocated a spontaneous binding. In vitro observations were further complemented by the calculation of binding free energy by molecular docking and interactions with the functionally-important residues of the active site pocket of MARK4. This study signifies the implications of AChE inhibitors, RT, and DP in Alzheimer’s therapy targeting MARK4.

The Effects of microRNA-515-5p on the Toll-Like Receptor 4 (TLR4)/JNK Signaling Pathway and WNT1-Inducible-Signaling Pathway Protein 1 (WISP-1) Expression in Rheumatoid Arthritis Fibroblast-Like Synovial (RAFLS) Cells Following Treatment with Receptor Activator of Nuclear Factor-kappa-B Ligand (RANKL)

BACKGROUND This study aimed to investigate the effects of microRNA-515-5p (miR-515-5p) on the expression of the WNT1-inducible-signaling pathway protein 1 (WISP-1) gene in rheumatoid arthritis fibroblast-like synovial (RAFLS) cells following treatment with the receptor activator of nuclear factor-kappa-B ligand (RANKL). MATERIAL AND METHODS RAFLS cells were cultured in vitro and were divided into six study groups: a normal control group; a miR-515-5p mimic group; a miR-515-5p inhibitor group; a RANKL (50 ng/ml) treatment group; a miR-515-5p mimic+RANKL treatment group; and a miR-515-5p inhibitor+RANKL treatment group. The luciferase assay was used to determine the effects of miR-515-5p on the WISP1 expression. Cell proliferation, cell apoptosis, the cell cycle, and protein expression were determined using the Cell Counting Kit-8 (CCK-8) assay, flow cytometry, Western blot, and real-time polymerase chain reaction (RT-PCR). RESULTS The luciferase assay showed that the effects of miR-515-on the 3'-UTR of WISP1 inhibited the gene expression. The miR-515-5p mimics promoted cell proliferation, reduced apoptosis, and promoted the cell cycle. The miR-515-5p mimics reduced, the expression of TLR4, WISP1, and JNK at the mRNA level, while the miR-515-5p inhibitor promoted the expression of TLR4, WISP1, and JNK. Both the miR-515-5p inhibitor and mimic promoted the phosphorylation of AKT in RAFLS cells treated with or without RANKL compared with the control, and the miR-515-5p inhibitor promoted the phosphorylation of JNK in the RAFLS cells. CONCLUSIONS In RAFLS cells, miR-515-5p inhibited the expression of the WISP1 gene, and treatment with RANKL inhibited the TLR4/JNK signaling pathway.

H3K27ac-activated LINC00519 promotes lung squamous cell carcinoma progression by targeting miR-450b-5p/miR-515-5p/YAP1 axis

Objectives

Long non‐coding RNAs (lncRNAs) are extensively reported as participants in the biological process of diverse malignancies, including lung squamous cell carcinoma (LUSC). Long intergenic non‐protein coding RNA 519 (LINC00519) is identified as a novel lncRNA which has not yet been studied in cancers.

Materials and Methods

LINC00519 expression was detected by qRT‐PCR. The effect of LINC00519 on LUSC cellular activities was determined by in vitro and in vivo assays. Subcellular fractionation and FISH assays were conducted to identify the localization of LINC00519. The interaction between miR‐450b‐5p/miR‐515‐5p and LINC00519/YAP1 was verified by RIP, RNA pull‐down and luciferase reporter assays.

Results

Elevated level of LINC00519 was identified in LUSC tissues and cell lines. High LINC00519 level predicted unsatisfactory prognosis. Then, loss‐of‐function assays suggested the inhibitive role of silenced LINC00519 in cell proliferation, migration, invasion and tumour growth and promoting effect on cell apoptosis in LUSC. Mechanically, LINC00519 was activated by H3K27 acetylation (H3K27ac). Moreover, LINC00519 sponged miR‐450b‐5p and miR‐515‐5p to up‐regulate Yes1 associated transcriptional regulator (YAP1). Additionally, miR‐450b‐5p and miR‐515‐5p elicited anti‐carcinogenic effects in LUSC. Finally, rescue assays validated the effect of LINC00519‐miR‐450b‐5p‐miR‐515‐5p‐YAP1 axis in LUSC.

Conclusions

H3K27ac‐activated LINC00519 acts as a competing endogenous RNA (ceRNA) to promote LUSC progression by targeting miR‐450b‐5p/miR‐515‐5p/YAP1 axis.

Interspecies Communication in Holobionts by Non-Coding RNA Exchange

Complex organisms are associations of different cells that coexist and collaborate creating a living consortium, the holobiont. The relationships between the holobiont members are essential for proper homeostasis of the organisms, and they are founded on the establishment of complex inter-connections between all the cells. Non-coding RNAs are regulatory molecules that can also act as communication signals between cells, being involved in either homeostasis or dysbiosis of the holobionts. Eukaryotic and prokaryotic cells can transmit signals via non-coding RNAs while using specific extracellular conveyors that travel to the target cell and can be translated into a regulatory response by dedicated molecular machinery. Within holobionts, non-coding RNA regulatory signaling is involved in symbiotic and pathogenic relationships among the cells. This review analyzes current knowledge regarding the role of non-coding RNAs in cell-to-cell communication, with a special focus on the signaling between cells in multi-organism consortia.

The network of non-coding RNAs and their molecular targets in breast cancer

Background

Non-coding RNAs are now recognized as fundamental components of the cellular processes. Non-coding RNAs are composed of different classes, including microRNAs (miRNAs) and long non-coding RNAs (lncRNAs). Their detailed roles in breast cancer are still under scrutiny.

Main body

We systematically reviewed from recent literature the many functional and physical interactions of non-coding RNAs in breast cancer. We used a data driven approach to establish the network of direct, and indirect, interactions. Human curation was essential to de-convolute and critically assess the experimental approaches in the reviewed articles. To enrol the scientific papers in our article cohort, due to the short time span (shorter than 5 years) we considered the journal impact factor rather than the citation number.

The outcome of our work is the formal establishment of different sub-networks composed by non-coding RNAs and coding genes with validated relations in human breast cancer. This review describes in a concise and unbiased fashion the core of our current knowledge on the role of lncRNAs, miRNAs and other non-coding RNAs in breast cancer.

Conclusions

A number of coding/non-coding gene interactions have been investigated in breast cancer during recent years and their full extent is still being established. Here, we have unveiled some of the most important networks embracing those interactions, and described their involvement in cancer development and in its malignant progression.