miRNA-204 suppresses human non-small cell lung cancer by targeting ATF2

ATF family members as therapeutic targets in cancer: From mechanisms to pharmacological interventions

The activating transcription factor (ATF)/ cAMP-response element binding protein (CREB) family represents a large group of basic zone leucine zip (bZIP) transcription factors (TFs) with a variety of physiological functions, such as endoplasmic reticulum (ER) stress, amino acid stress, heat stress, oxidative stress, integrated stress response (ISR) and thus inducing cell survival or apoptosis. Interestingly, ATF family has been increasingly implicated in autophagy and ferroptosis in recent years. Thus, the ATF family is important for homeostasis and its dysregulation may promote disease progression including cancer. Current therapeutic approaches to modulate the ATF family include direct modulators, upstream modulators, post-translational modifications (PTMs) modulators. This review summarizes the structural domain and the PTMs feature of the ATF/CREB family and comprehensively explores the molecular regulatory mechanisms. On this basis, their pathways affecting proliferation, metastasis, and drug resistance in various types of cancer cells are sorted out and discussed. We then systematically summarize the status of the therapeutic applications of existing ATF family modulators and finally look forward to the future prospect of clinical applications in the treatment of tumors by modulating the ATF family.

Role of MicroRNA-204 in Regulating the Hallmarks of Breast Cancer: An Update

microRNA-204-5p (miR-204) is a small noncoding RNA with diverse regulatory roles in breast cancer (BC) development and progression. miR-204 is implicated in the instauration of fundamental traits acquired during the multistep development of BC, known as the hallmarks of cancer. It may act as a potent tumor suppressor by inhibiting key cellular processes like angiogenesis, vasculogenic mimicry, invasion, migration, and metastasis. It achieves this by targeting multiple master genes involved in these processes, including HIF-1α, β-catenin, VEGFA, TGFBR2, FAK, FOXA1, among others. Additionally, miR-204 modulates signaling pathways like PI3K/AKT and interacts with HOTAIR and DSCAM-AS1 lncRNAs, further influencing tumor progression. Beyond its direct effects on tumor cells, miR-204 shapes the tumor microenvironment by regulating immune cell infiltration, suppressing pro-tumorigenic cytokine production, and potentially influencing immunotherapy response. Moreover, miR-204 plays a crucial role in metabolic reprogramming by directly suppressing metabolic genes within tumor cells, indirectly affecting metabolism through exosome signaling, and remodeling metabolic flux within the tumor microenvironment. This review aims to present an update on the current knowledge regarding the role of miR-204 in the hallmarks of BC. In conclusion, miR-204 is a potential therapeutic target and prognostic marker in BC, emphasizing the need for further research to fully elucidate its complex roles in orchestrating aggressive BC behavior.

The two-faced role of ATF2 on cisplatin response in gastric cancer depends on p53 context

Background

Activating transcription factor-2 (ATF2) is a member of the basic leucine zipper family of DNA-binding proteins, which exhibits both oncogenic and tumor suppression activity in different tumors. However, the molecular mechanism of its dual function in cancer chemotherapy especially in gastric cancer has still not been elucidated.

Methods

The protein expression and location of ATF2 in gastric cancer tissues was detected with immunohistochemistry assay, and the clinical significance was analyzed using TCGA and GEO database. The activation and impact of ATF2 in cisplatin treated cells were evaluated with western blot, incucyte live cell analysis, clone formation and tumor xenografts assays. Interaction between ATF2 and p53 was confirmed with immunoprecipitation and GST-pull down. Potential molecular mechanism of ATF2 in different p53 status cells was analyzed with RNA sequencing and real-time quantitative PCR.

Results

ATF2 mainly located in the nucleus of cancer cells, higher ATF2 level was associated with poor five-year survival of gastric patients, especially in those undergone chemotherapy treatment. Cisplatin treatment significantly activated ATF2 in p53 mutant cells. ATF2 could interact with the trans-activation domain of p53 and enhance cisplatin sensitivity in p53 wild type cell lines, while promoted cell survival in mutant p53 cancer cells by affecting ERK1/2 pathway.

Conclusions

This study confirmed the effect of ATF2 on cisplatin sensitivity was associated with the functional status of p53 in gastric cancer cells. Integrated analysis of ATF2 expression and P53 status could be used to evaluate the chemotherapy sensitivity and prognosis of gastric cancer patients.

Supplementary information

The online version contains supplementary material available at 10.1186/s13578-022-00802-w.

MicroRNA-204-5p: A pivotal tumor suppressor

MicroRNAs (miRNAs) are a class of non-coding single-stranded RNA molecules with a length of approximately 18-25 nt nucleotides that regulate gene expression post-transcriptionally. MiR-204-5p originates from the sixth intron of the transient receptor potential cation channel subfamily M member 3 (TRPM3) gene. MiR-204-5p is frequently downregulated in various cancer types and is related to the clinicopathological characteristics and prognosis of cancer patients. So far, many studies have determined that miR-204-5p functions as a tumor suppressor for its extensive and powerful capacity to inhibit tumor proliferation, metastasis, autophagy, and chemoresistance in multiple cancer types. MiR-204-5p appears to be a promising prognostic biomarker and a therapeutic target for human cancers. This review summarized the latest advances on the role of miR-204-5p in human cancers.

A cerebrospinal fluid microRNA analysis: Progressive supranuclear palsy

Progressive supranuclear palsy (PSP) is a neurodegenerative tauopathy described as a syndrome of postural instability, supranuclear vertical gaze palsy, dysarthria, dystonic rigidity of the neck and trunk, dementia, and pseudobulbar palsy. The clinical diagnosis of PSP is often difficult because there are no established biomarkers, and diagnosis is currently based on clinical and imaging findings. Furthermore, the etiology and pathogenesis of PSP remain unknown. Dysregulation of microRNAs (miRNAs/miRs) has been reported to serve an important role in neurodegenerative diseases. However, the miRNA profiles of patients with PSP are rarely reported. The present study aimed to examine cerebrospinal fluid miRNAs, which are considered to be more sensitive indicators of changes in the brain, to elucidate the pathophysiology of PSP and to establish specific biomarkers for diagnosis. The present study used a microarray chip containing 2,632 miRNAs to examine cerebrospinal fluid miRNA expression levels in 11 patients with PSP aged 68–82 years. A total of 8 age- and sex-matched controls were also included. A total of 38 miRNAs were significantly upregulated and one miRNA was significantly downregulated in the cerebrospinal fluid of patients with PSP. The patients were divided into two groups based on disease stage (early onset and advanced), and changes in miRNA expression were examined. The miRNAs that were most significantly upregulated or downregulated in the early onset group were miR-204-3p, miR-873-3p and miR-6840-5p. The target genes of these miRNAs were associated with molecules related to the ubiquitin-proteasome system and autophagy pathway. Furthermore, these miRNAs were found to target genes that have been reported to have epigenetic changes following an epigenome-wide association study of brain tissues of patients with PSP. This suggested that these miRNAs and genes may have some involvement in the pathogenesis of PSP. However, the sample size of the present study was small; therefore, a greater number of patients with PSP should be examined in future studies.

Epi-miRNAs: Regulators of the Histone Modification Machinery in Human Cancer

Cancer is a leading cause of death and disability worldwide. Epigenetic deregulation is one of the most critical mechanisms in carcinogenesis and can be classified into effects on DNA methylation and histone modification. MicroRNAs are small noncoding RNAs involved in fine-tuning their target genes after transcription. Various microRNAs control the expression of histone modifiers and are involved in a variety of cancers. Therefore, overexpression or downregulation of microRNAs can alter cell fate and cause malignancies. In this review, we discuss the role of microRNAs in regulating the histone modification machinery in various cancers, with a focus on the histone-modifying enzymes such as acetylases, deacetylases, methyltransferases, demethylases, kinases, phosphatases, desumoylases, ubiquitinases, and deubiquitinases. Understanding of microRNA-related aberrations underlying histone modifiers in pathogenesis of different cancers can help identify novel therapeutic targets or early detection approaches that allow better management of patients or monitoring of treatment response.

MicroRNAs Involved in Oxidative Stress Processes Regulating Physiological and Pathological Responses

Oxidative stress influences several physiological and pathological cellular events, including cell differentiation, excessive growth, proliferation, apoptosis, and the inflammatory response. Therefore, oxidative stress is involved in the pathogenesis of various diseases, including pulmonary fibrosis, epilepsy, hypertension, atherosclerosis, Parkinson's disease, cardiovascular disease, and Alzheimer's disease. Recent studies have shown that several microRNAs (miRNAs) are involved in developing various diseases caused by oxidative stress and that miRNAs may be helpful to determine the inflammatory characteristics of immune responses during infection and disease. This review describes the known effects of miRNAs on reactive oxygen species to induce oxidative stress and the miRNA regulatory mechanisms involved in the uncoupling of Keap1-Nrf2 complexes. Finally, we summarized the functions of miRNAs in several antioxidant genes. Understanding the crosstalk between miRNAs and oxidative stress-inducing factors during physiological and pathological cellular events may have implications for designing more effective treatments for immune diseases.

EHF enhances malignancy by modulating AKT and MAPK/ERK signaling in non‑small cell lung cancer cells

Overexpression of ETS‑homologous factor (EHF) in non‑small cell lung cancer (NSCLC) is associated with poor patient prognosis. To explore the mechanism of the effect of EHF in NSCLC, EHF expression was examined in NSCLC and its role in cell proliferation, invasion, cell cycle, and apoptosis of NSCLC cells was evaluated by overexpressing EHF and/or knocking down EHF expression in NSCLC cells in vitro and in cancer cell grafted mice in vivo. The results revealed that the knockdown of EHF expression in NSCLC with siRNA significantly inhibited cell proliferation and invasion, arrested the cell cycle at the G₀/G₁ phase, and induced apoptosis, whereas overexpression of EHF in NSCLC promoted cell proliferation, tumor growth, and cancer cell migration in vitro. The in vivo experiments demonstrated that siRNA‑mediated downregulation of EHF expression in NSCLC cells significantly suppressed tumor growth in xenografted nude mice as compared to cancer progression in the mice grafted with NSCLC cells transfected with non‑specific control siRNA. The biochemical analyses revealed that EHF promoted NSCLC growth by regulating the transcription of Erb‑B2 receptor tyrosine kinase 2/3 (ERBB2, ERBB3) and mesenchymal‑epithelial transition (MET) factor tyrosine kinase receptors and modulating the AKT and ERK signaling pathways in the NSCLC cells. The present findings indicated that EHF could be used as a prognostic marker for NSCLC, and tyrosine kinase receptors of ERBB2, ERBB3 and MET could be drug targets for NSCLC treatment.

MicroRNA-204 plays a role as a tumor suppressor in Newcastle disease virus-induced oncolysis in lung cancer A549 cells

Tumor development and progression are closely associated with various microRNAs (miRNAs/miRs). We have previously shown that Newcastle disease virus (NDV) strain 7793 induces oncolysis in lung cancer. However, how NDV exerts its oncolytic effect on lung cancer remains to be investigated. The present study assessed the role of miR-204 in the NDV-induced oncolysis of lung cancer A549 cells by oncolysis induction in vitro. miR-204 was significantly upregulated in NDV-treated A549 cells. Overexpression or inhibition of miR-204 was significantly associated with NDV-induced oncolysis in A549 cells. Caspase-3 and Bax, major regulators of the apoptosis pathway, were regulated by miR-204, and the association between caspase-3-related apoptosis and miR-204 was identified in NDV-mediated oncolysis. These data demonstrated that miR-204 as a tumor suppressor played a role in NDV-induced oncolysis in lung cancer cells. The present study demonstrates the potential of strategies using miRs to improve oncolytic NDV potency, and highlights miR-204 as a tumor suppressor in NDV-induced oncolysis of lung cancer cells.

MicroRNA-95-3p serves as a contributor to cisplatin resistance in human gastric cancer cells by targeting EMP1/PI3K/AKT signaling

MicroRNAs (miRNAs) are thought to be involved in the development of cisplatin (DDP) resistance in gastric cancer (GC). Using RNA sequencing analysis (RNA-seq), we found that miR-95-3p is associated with DDP resistance in GC. We discovered that miR-95-3p is highly expressed in DDP-resistant GC tissues and cell lines (SGC7901/DDP and AGS/DDP). Furthermore, results from the BrdU and MTT assays indicated that miR-95-3p promotes GC cell proliferation. Additionally, data from transwell chamber assay, wound healing test and in vivo experiments illustrated that miR-95-3p can effectively promote invasion, migration and tumorigenic capacity, respectively, of DDP-resistant GC cells. Subsequently, results from dual luciferase assay and qRT-PCR collectively indicated that EMP1 is a target of miR-95-3p with inhibitory function through suppression of the EMT process and drug-resistance proteins. Furthermore, PI3K/AKT was identified as a downstream pathway of miR-95-3p, which promotes DDP resistance in GC. In summary, miR-95-3p helped develop DDP-resistance through down-regulation of EMP1 and increasing phosphorylation of the PI3K/Akt pathway in GC.

The role of microRNAs in cell death pathways

MicroRNAs (miRNAs) are a class of noncoding RNAs that negatively regulate target messenger RNAs. In multicellular eukaryotes, numerous miRNAs perform basic cellular functions, including cell proliferation, differentiation, and death. Abnormal expression of miRNAs weakens or modifies various apoptosis pathways, leading to the development of human cancer. Cell death occurs in an active manner that maintains tissue homeostasis and eliminates potentially harmful cells through regulated cell death processes, including apoptosis, autophagic cell death, and necroptosis. In this review, we discuss the involvement of miRNAs in regulating cell death pathways in cancers and the potential therapeutic functions of miRNAs in cancer treatment.

microRNA -378a-3p Restrains the Proliferation of Retinoblastoma Cells but Promotes Apoptosis of Retinoblastoma Cells via Inhibition of FOXG1

Purpose

More recently, literature has emerged providing findings about the novelty of microRNAs (miR)-targeted therapeutics in the treatment of retinoblastoma (RB). The prime objective of this study was to identify the potential role of miR-378a-3p and its regulation in RB cells via forkhead box G1 (FOXG1).

Methods

The expression of miR-378a-3p and FOXG1 in the clinical RB tissues was determined using RNA quantitation and Western blot assays. The interaction between miR-378a-3p and FOXG1 was identified using dual luciferase reporter gene assay. The potential effects of miR-378a-3p on the RB cell biological processes were evaluated by conducting gain- and loss-of-function studies of miR-378a-3p and FOXG1, followed by cell viability, cell cycle progression, and apoptosis measurements. Furthermore, experiments were performed in nude mice to assess its effects on tumor formation.

Results

miR-378a-3p was poorly expressed, whereas FOXG1 was highly expressed in RB tissues and cells. miR-378a-3p bound to the FOXG1 3′ untranslated region and negatively modulated its expression. The overexpression of miR-378a-3p was found to decrease RB cell viability and to promote cell apoptosis in vitro, whereas overexpressed FOXG1 reversed the regulatory effects of miR-378a-3p on RB cellular behaviors. In nude mice, the restoration of miR-378a-3p by miR-378a-3p agomir was shown to play a role in the reduction of tumor volume and size relative to nude mice injected with negative control-agomir.

Conclusions

Our findings identified that increased miR-378a-3p exerted an inhibitory effect on RB cell proliferation by targeting FOXG1, suggesting the role of miR-378a-3p as a novel therapeutic target for RB.

Exosomal microRNA-26b-5p down-regulates ATF2 to enhance radiosensitivity of lung adenocarcinoma cells

Lung adenocarcinoma (LUAD), as the most common subtype of non‐small cell lung cancer, is responsible for more than 500 000 deaths worldwide annually. In this study, we identify a novel microRNA‐26b‐5p (miR‐26b‐5p) and elucidated its function on LUAD. The survival rate of parent LUAD cells and radiation‐resistant LUAD cells were determined using clonogenic survival assay. We overexpressed or inhibited miR‐26b‐5p in LUAD, and the correlation between activating transcription factor 2 (ATF2) and miR‐26b‐5p was determined using integrated bioinformatics analysis and dual‐luciferase reporter gene assay. Exosomes derived from A549 cell lines were then detected using Western blot assay, followed by co‐transfection with radiation‐resistant A549R cells. LUAD tissues and serum were collected, followed by miR‐26b‐5p relative expression quantification using RT‐qPCR. miR‐26b‐5p was identified as the most differentially expressed miRNA and was down‐regulated in LUAD. Radiation‐resistant cells were more resistant to X‐radiation compared with parent cells. miR‐26b‐5p overexpression and X‐irradiation led to enhanced radiosensitivity of LUAD cells. ATF2 was negatively targeted by miR‐26b‐5p. Exosomal miR‐26b‐5p derived from A549 cells could be transported to irradiation‐resistant LUAD cells and inhibit ATF2 expression to promote DNA damage, apoptosis and radiosensitivity of LUAD cells, which was verified using serum‐based miR‐26b‐5p. Our results show a regulatory network of miR‐26b‐5p on radiosensitivity of LUAD cells, which may serve as a non‐invasive biomarker for LUAD.

microRNA-100 functions as a tumor suppressor in non-small cell lung cancer via regulating epithelial-mesenchymal transition and Wnt/β-catenin by targeting HOXA1

BACKGROUND

Non-small cell lung cancer (NSCLC) is a leading subtype in lung cancer, with high morbidities and mortalities worldwide. microRNA (miRNA) has appeared to play indispensable roles in a variety of solid carcinomas. The current study focused on the functions of miR-100 in NSCLC.

METHODS

qRT-PCR was performed to detect miR-100 and HOXA1 expressions in NSCLC tissues and cells. MTT and transwell assays were used to determine the functions of miR-100 in NSCLC cell proliferation, invasion and migration abilities. Western blot was used to measure related protein expressions.

RESULTS

qRT-PCR results showed that miR-100 expressions were dramatically decreased in NSCLC tissues. MTT assays indicated that miR-100 restoration inhibited NSCLC cell proliferation. Furthermore, transwell assay was performed to determine the impacts of miR-100 on NSCLC invasion and migration abilities. As expected, the invasion and migration capacities were significantly repressed. Direct interactions between HOXA1 and miR-100 were also verified via dual-luciferase reporter assays. Western blot analysis demonstrated that miR-100 exerted suppressive functions via regulating EMT and Wnt/β-catenin in NSCLC cells.

CONCLUSIONS

Our results showed that miR-100 served antitumor roles in NSCLC, providing new evidence of miR-100 as a promising therapeutic biomarker in NSCLC.

Dysregulated miRNA in a cancer-prone environment: A study of gastric non-neoplastic mucosa

Understanding cancer-prone environments is important to efficiently detect and prevent cancers. The associations between miRNA and cancer-prone environments are still largely unknown in gastric cancer (GC). Six miRNAs that are differentially expressed during gastric carcinogenesis were selected, and quantitative real-time PCR was performed in an independent training set (fresh non-tumor and tumor samples from 18 GC patients) and validation sets (set 1 with formalin-fixed paraffin-embedded non-tumor and tumor samples from 19 solitary GC and set 2 with 37 multiple GC patients). The results were compared with those of 37 gastric mucosa from 20 healthy volunteers. The expression levels of miR-26a, miR-375, and miR-1260 in gastric mucosa from healthy volunteers were statistically higher than that of non-tumorous gastric mucosa located 3 cm apart from the GC in the training set (miR-26a, P < 0.0001; miR-375, P = 0.0049; miR-1260, P = 0.0172), validation set 1 (miR-26a and miR-375, P < 0.0001; miR-1260, P = 0.0008), and validation set 2 (miR-26a, miR-375, and miR-1260, P < 0.0001). And a combination of miR-26a and miR-1260 showed the highest area under the curve value of 0.89. miRNAs are differentially expressed in non-neoplastic gastric mucosa and can be used as a biomarker to predict cancer-prone environments.

Non-coding RNA profile in lung cancer

Lung cancer is the most frequently diagnosed malignancy and the leading source of cancer-associated mortality. This kind of cancer has heterogeneous nature and is divided into two broad classes of small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC). In addition to aberrant expression of several signaling pathways and oncogenes, lung cancer is associated with dysregulation of expression of non-coding RNAs including both long non-coding RNAs (lncRNAs) and miRNAs. These aberrantly expressed transcripts are putative therapeutic targets and diagnostic/ prognostic markers. Integrative assessment of expression of lncRNAs, miRNAs and mRNAs has led to construction of competing endogenous RNA networks in which several lncRNAs act as molecular sponges to inhibit regulatory function of miRNAs on mRNAs. Notably, some of these networks seem to have subtype-specific functions in lung cancer. In this review, we summarize recent findings about the importance of these networks in the pathogenesis of lung cancer and provide a list of onco-miRNAs, tumor suppressor miRNAs, oncogenic lncRNAs and tumor suppressor lncRNAs based on their roles in the carcinogenic process in lung cancer.

Downregulation of hsa-microRNA-204-5p and identification of its potential regulatory network in non-small cell lung cancer: RT-qPCR, bioinformatic- and meta-analyses

Background

Pulmonary malignant neoplasms have a high worldwide morbidity and mortality, so the study of these malignancies using microRNAs (miRNAs) has attracted great interest and enthusiasm. The aim of this study was to determine the clinical effect of hsa-microRNA-204-5p (miR-204-5p) and its underlying molecular mechanisms in non-small cell lung cancer (NSCLC).

Methods

Expression of miR-204-5p was investigated by real-time quantitative PCR (RT-qPCR). After data mining from public online repositories, several integrative assessment methods, including receiver operating characteristic (ROC) curves, hazard ratios (HR) with 95% confidence intervals (95% CI), and comprehensive meta-analyses, were conducted to explore the expression and clinical utility of miR-204-5p. The potential objects regulated and controlled by miR-204-5p in the course of NSCLC were identified by estimated target prediction and analysis. The regulatory network of miR-204-5p, with its target genes and transcription factors (TFs), was structured from database evidence and literature references.

Results

The expression of miR-204-5p was downregulated in NSCLC, and the downtrend was related to gender, histological type, vascular invasion, tumor size, clinicopathologic grade and lymph node metastasis (P<0.05). MiR-204-5p was useful in prognosis, but was deemed unsuitable at present as an auxiliary diagnostic or prognostic risk factor for NSCLC due to the lack of statistical significance in meta-analyses and absence of large-scale investigations. Gene enrichment and annotation analyses identified miR-204-5p candidate targets that took part in various genetic activities and biological functions. The predicted TFs, like MAX, MYC, and RUNX1, interfered in regulatory networks involving miR-204-5p and its predicted hub genes, though a modulatory loop or axis of the miRNA-TF-gene that was out of range with shortage in database prediction, experimental proof and literature confirmation.

Conclusions

The frequently observed decrease in miR-204-5p was helpful for NSCLC diagnosis. The estimated target genes and TFs contributed to the anti-oncogene effects of miR-204-5p.

Circ_MDM2_000139, Circ_ATF2_001418, Circ_CDC25C_002079, and Circ_BIRC6_001271 Are Involved in the Functions of XAV939 in Non-Small Cell Lung Cancer

Background

The small molecule inhibitor XAV939 could inhibit the proliferation and promote the apoptosis of non-small cell lung cancer (NSCLC) cells. This study was conducted to identify the key circular RNAs (circRNAs) and microRNAs (miRNAs) in XAV939-treated NSCLC cells.

Methods

After grouping, the NCL-H1299 cells in the treatment group were treated by 10 μM XAV939 for 12 h. RNA-sequencing was performed, and then the differentially expressed circRNAs (DE-circRNAs) were analyzed by the edgeR package. Using the clusterprofiler package, enrichment analysis for the hosting genes of the DE-circRNAs was performed. Using Cytoscape software, the miRNA-circRNA regulatory network was built for the disease-associated miRNAs and the DE-circRNAs. The DE-circRNAs that could translate into proteins were predicted using circBank database and IRESfinder tool. Finally, the transcription factor (TF)-circRNA regulatory network was built by Cytoscape software. In addition, A549 and HCC-827 cell treatment with XAV939 were used to verify the relative expression levels of key DE-circRNAs.

Results

There were 106 DE-circRNAs (including 61 upregulated circRNAs and 45 downregulated circRNAs) between treatment and control groups. Enrichment analysis for the hosting genes of the DE-circRNAs showed that ATF2 was enriched in the TNF signaling pathway. Disease association analysis indicated that 8 circRNAs (including circ_MDM2_000139, circ_ATF2_001418, circ_CDC25C_002079, and circ_BIRC6_001271) were correlated with NSCLC. In the miRNA-circRNA regulatory network, let-7 family members⟶circ_MDM2_000139, miR-16-5p/miR-134-5p⟶circ_ATF2_001418, miR-133b⟶circ_BIRC6_001271, and miR-221-3p/miR-222-3p⟶circ_CDC25C_002079 regulatory pairs were involved. A total of 47 DE-circRNAs could translate into proteins. Additionally, circ_MDM2_000139 was targeted by the TF POLR2A. The verification test showed that the relative expression levels of circ_MDM2_000139, circ_CDC25C_002079, circ_ATF2_001418, and circ_DICER1_000834 in A549 and HCC-827 cell treatment with XAV939 were downregulated comparing with the control.

Conclusions

Let-7 family members and POLR2A targeting circ_MDM2_000139, miR-16-5p/miR-134-5p targeting circ_ATF2_001418, miR-133b targeting circ_BIRC6_001271, and miR-221-3p/miR-222-3p targeting circ_CDC25C_002079 might be related to the mechanism in the treatment of NSCLC by XAV939.

Expression and potential molecular mechanisms of miR‑204‑5p in breast cancer, based on bioinformatics and a meta‑analysis of 2,306 cases

Breast cancer (BC) is the most common cancer among women worldwide. However, there is insufficient research that focuses on the expression and molecular mechanisms of microRNA (miR)‑204‑5p in BC. In the current study, data were downloaded from the Cancer Genome Atlas (TCGA), the Gene Expression Omnibus (GEO) and the University of California Santa Cruz (UCSC) Xena databases. They were then used to undertake a meta‑analysis that leveraged the standard mean difference (SMD) and summarized receiver operating characteristic (sROC) to evaluate the expression of the precursor miR‑204 and mature miR‑204‑5p in BC. Additionally, an intersection of predicted genes, differentially expressed genes (DEGs) from the TCGA database and the GEO database were plotted to acquire desirable putative genes. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and protein‑protein interaction (PPI) network analyses were performed to assess the potential pathways and hub genes of miR‑204‑5p in BC. A decreased trend in precursor miR‑204 expression was detected in 1,077 BC tissue samples in comparison to 104 para‑carcinoma tissue samples in the TCGA database. Further, the expression of mature miR‑204‑5p was markedly downregulated in 756 BC tissue samples in comparison to 76 para‑carcinoma tissue samples in the UCSC Xena database. The outcome of the SMD from meta‑analysis also indicated that the expression of miR‑204‑5p was markedly reduced in 2,306 BC tissue samples in comparison to 367 para‑carcinoma tissue samples. Additionally, the ROC and sROC values indicated that miR‑204‑5p had a great discriminatory capacity for BC. In GO analysis, 'cell development', 'cell surface activity', and 'receptor agonist activity' were the most enriched terms; in KEGG analysis, 'endocytosis' was significantly enriched. Rac GTPase activating protein 1 (RACGAP1) was considered the hub gene in the PPI network. In conclusion, miR‑204‑5p may serve a suppressor role in the oncogenesis and advancement of BC, and miR‑204‑5p may have crucial functions in BC by targeting RACGAP1.

MicroRNA-204 deregulation in lung adenocarcinoma controls the biological behaviors of endothelial cells potentially by modulating Janus kinase 2-signal transducer and activator of transcription 3 pathway

MicroRNAs (miRNAs) have been implicated in a wide range of biological processes including angiogenesis. MiR-204 was identified as a tumor suppressor in multiple cancer types, including lung adenocarcinoma. However, the function of miR-204 in lung tumor angiogenesis remains unknown. In this study, we found that the miR-204 expression was decreased in lung adenocarcinoma based on the cancer genome atlas (TCGA) analysis and gain-of-function experiment showed that miR-204 promoted cancer cell apoptosis and suppressed cell proliferation, migration in vitro and tumor growth in vivo. Functionally, both the tube formation and migration abilities of human umbilical vein endothelial cells (HUVECs) were suppressed by conditioned media from lung cancer A549 cells with miR-204 overexpression. Meanwhile, these conditioned media inhibited proliferation and promoted apoptosis in HUVECs. The key angiogenesis inducer hypoxia inducible factor-1α (HIF1α) and the pro-angiogenic mediators vascular endothelial growth factor and platelet-derived growth factor were decreased in A549 cells transfected with miR-204 mimics. Mechanistically, miR-204 could target Janus kinase 2 (JAK2) and further impaired signal transducer and activator of transcription 3 both in vitro and in vivo. Inhibition of JAK2 or signal transducer and activator of transcription 3 (STAT3) activity with small chemical inhibitors in A549 cells impaired lung adenocarcinoma angiogenesis in vitro. Meanwhile, conditional media from interleukin 6-treated lung normal epithelial cells significantly promoted tube formation of HUVEC, which was disturbed by miR-204 overexpression. Taken together, our findings demonstrate that miR-204 attenuates angiogenesis in lung adenocarcinoma potentially via JAK2-STAT3 pathway. Clinically, the miR-204/JAK2/STAT3 signaling pathway is a putative therapeutic target in lung adenocarcinoma. © 2017 IUBMB Life, 70(1):81-91, 2018.

Prognostic value of microRNAs in lung cancer: A systematic review and meta-analysis

Lung cancer is one of the leading causes of cancer-associated mortality throughout the world. The prognosis of the disease depends on many factors including the stage and type of cancer. Many studies have identified various microRNAs (miRNAs) that affect the prognosis of lung cancer. In order to systemically analyze the available clinical data, the present study performed a meta-analysis to examine all evidence on the potential role of miRNAs as novel predictors of survival in lung cancer. Literature published in English prior to February 1st, 2018 was searched through PubMed to review all of the associations between individual miRNAs and groups of miRNAs with the prognosis of lung cancer. Data was extracted using standard forms and pooled odds ratios with 95% confidence intervals (CIs) were calculated. A total of 15 eligible studies were included in the meta-analysis. These represented 1,753 lung cancer patients and 20 miRNAs. A total of 8 downregulated miRNAs were associated with poorer overall survival (OS) [hazard ratio (HR)=0.59, 95% CI: 0.47–0.75, P<1×10⁻⁴], while 10 upregulated miRNAs were associated with poorer OS (HR=1.76, 95% CI: 1.31–2.35, P<1×10⁻⁴). Additionally, low miRNA expression was associated with lymph node metastasis [LNM; relative risk (RR)=0.53, 95% CI: 0.46–0.61, P<1×10⁻⁴]. The expression of miRNAs was not associated with lung cancer stage (RR=1.07, 95% CI: 0.94–1.22, P=0.23). Expression levels of different miRNAs were associated with the OS and LNM of patients with lung cancer. These miRNAs may be applied as potential prognostic markers in lung cancer.

Pathological bases and clinical impact of long noncoding RNAs in prostate cancer: a new budding star

Long non-coding RNAs (lncRNAs) are functional RNAs longer than 200 nucleotides. Recent advances in the non-protein coding part of human genome analysis have discovered extensive transcription of large RNA transcripts that lack coding protein function, termed non-coding RNA (ncRNA). It is becoming evident that lncRNAs may be an important class of pervasive genes involved in carcinogenesis and metastasis. However, the biological and molecular mechanisms of lncRNAs in diverse diseases are not yet fully understood. Thus, it is anticipated that more efforts should be made to clarify the lncRNA world. Moreover, accumulating evidence has demonstrated that many lncRNAs are dysregulated in prostate cancer (PC) and closely related to tumorigenesis, metastasis, and prognosis or diagnosis. In this review, we will briefly outline the regulation and functional role of lncRNAs in PC. Finally, we discussed the potential of lncRNAs as prospective novel targets in PC treatment and biomarkers for PC diagnosis.

Decoding the Emerging Patterns Exhibited in Non-coding RNAs Characteristic of Lung Cancer with Regard to their Clinical Significance

Lung cancer continues to be the leading topic concerning global mortality rate caused by can-cer; it needs to be further investigated to reduce these dramatic unfavorable statistic data. Non-coding RNAs (ncRNAs) have been shown to be important cellular regulatory factors and the alteration of their expression levels has become correlated to extensive number of pathologies. Specifically, their expres-sion profiles are correlated with development and progression of lung cancer, generating great interest for further investigation. This review focuses on the complex role of non-coding RNAs, namely miR-NAs, piwi-interacting RNAs, small nucleolar RNAs, long non-coding RNAs and circular RNAs in the process of developing novel biomarkers for diagnostic and prognostic factors that can then be utilized for personalized therapies toward this devastating disease. To support the concept of personalized medi-cine, we will focus on the roles of miRNAs in lung cancer tumorigenesis, their use as diagnostic and prognostic biomarkers and their application for patient therapy.

Potential miRNA-target interactions for the screening of gastric carcinoma development in gastric adenoma/dysplasia

Although miRNA markers have been identified for the pathological development of gastric adenocarcinoma (GAC), the underlying molecule mechanism are still not fully understood. Moreover, some gastric adenoma/dysplasia may progress to GAC. In this study, the miRNA expression profiles in normal and paired low-/high-grade dysplasia were analyzed using Affymetrix Gene-Chip miRNA arrays. Of the total 2578 mature miRNA probe sets, ~1600 showed positive signals when the between normal and paired low-/high-grade dysplasia were compared. To verify the miRNA expression, qRT-PCR analysis was performed to quantify the expression of altered miRNAs between normal and paired low-/high-grade dysplasia. The analysis revealed that hsa-miR-421, hsa-miR-29b-1-5p, and hsa-miR-27b-5p were overexpressed in gastric low-/high-grade dysplasia and that based on these miRNA-target interactions, FBXO11 and CREBZF could be considered convincing markers for gastric cancer (GC) progression. Thus, we identified three miRNAs (hsa-miR-421, hsa-miR-29b-1-5p, and hsa-miR-27b-5p) with two mRNAs (FBXO11 and CREBZF) that might play an important role in the GC development from premalignant adenomas. Furthermore, these two target mRNAs and three miRNAs were predicted to be potential biomarkers for the progression of GC by miRNA-target interaction analysis.

MicroRNA‑21 increases cell viability and suppresses cellular apoptosis in non‑small cell lung cancer by regulating the PI3K/Akt signaling pathway

MicroRNA (miRNA/miR), a type of non‑coding RNA molecule, is able to inhibit the expression of target genes at multiple stagess. There are 800‑1,000 known miRNAs in the human genome, which serve important roles in cell proliferation, differentiation, apoptosis and migration. Previous studies have demonstrated that the expression of miR‑21 is upregulated in numerous types of malignant tumor, and that miR‑21 participates in the occurrence and development of tumors via complex regulatory mechanisms. The present study aimed to investigate the association between miR‑21 expression, cell viability and apoptosis in a lung cancer cell line, and to elucidate the potential mechanisms. miR‑21 or small interfering RNA against miR‑21 were transfected into A549 non‑small cell lung cancer cells. The mRNA expression of miR‑21 was confirmed. Cell viability and apoptosis were examined using MTT and flow cytometric assays, respectively. The expression of certain apoptosis‑associated proteins was detected by western blotting. The results of the present study demonstrated that miR‑21 was able to increase the proliferation of A549 cells by inhibiting cellular apoptosis. miR‑21 inhibited apoptosis by modulating the activation of the phosphatidylinositol 3‑kinase/Rac‑α serine/threonine protein kinase (Akt) pathway in A549 cells. Correspondingly, inhibition of Akt decreased the apoptosis of A549 cells in miR‑21 siRNA‑treated cells. Therefore, the results of the present study demonstrated that miR‑21 increased cell viability by inhibiting apoptosis, through regulation of Akt activation. The present study demonstrated that miR‑21 may be involved in the progression of lung cancer and may be a novel therapeutic target for the disease.

The protective value of miR-204-5p for prognosis and its potential gene network in various malignancies: a comprehensive exploration based on RNA-seq high-throughput data and bioinformatics

Purpose

The prognostic role of miR-204-5p (previous ID: miR-204) is varied and inconclusive in diverse types of malignant neoplasm. Therefore, the purposes of the study comprehensively explore the overall prognostic role of miR-204-5p based on high-throughput microRNA sequencing data, and to investigate the potential role of miR-204-5p via bioinformatics approaches.

Materials and Methods

The data of microRNA sequencing and survival were downloaded from The Cancer Genome Atlas (TCGA), and the prognostic value of miR-204-5p was analyzed by using Kaplan-Meier and univariate cox regressions. Then a meta-analysis was conducted with all TCGA data and relevant studies collected from literature. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated. The prospective molecular mechanism of miR-204-5p was also assessed at a functional level with Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG), and protein-to-protein interactions (PPI) network.

Results

From TCGA data, the prognostic value of miR-204-5p obviously varied among 20 types of cancers. The pooled HR was 0.928 (95% CI: 0.774-1.113, P = 0.386, 6203 cases of malignancies). For the meta-analysis based on 15 studies from literature, the pooled HR was 0.420 (95% CI: 0.306-0.576, P < 0.001, 1783 cases of malignancies) for overall survival (OS). Furthermore, the combined HR from both TCGA and literature was 0.708 (95% CI: 0.600-0.834, P < 0.001, 7986 cases of malignancies). Subgroup analyses revealed that miR-204-5p could act as a prognostic marker in cancers of respiratory system and digestive system. Functional analysis was conducted on genes predicted as targets (n = 2057) after the overlay genes from six out of twelve software were extracted. Two significant KEGG pathways were enriched (hsa04360: Axon guidance and hsa04722: Neurotrophin signaling pathway). PPI network revealed some hub genes/proteins (CDC42, SOS1, PIK3R1, MAPK1, PLCG1, ESR1, MAPK11, and AR).

Conclusions

The current study demonstrates that over-expression of miR-204-5p could be a protective factor for a certain group of cancers. Clinically, the low miR-204-5p level could gain a predictive value for a poor survival in cancers of respiratory system and digestive system. The detailed molecular mechanisms of miR-204-5p remain to be verified.

MicroRNA-targeted therapeutics for lung cancer treatment

INTRODUCTION

Lung cancer is one of the leading causes of cancer-related mortality worldwide. MicroRNAs (miRNAs) are endogenous non-coding small RNAs that repress the expression of a broad array of target genes. Many efforts have been made to therapeutically target miRNAs in cancer treatments using miRNA mimics and miRNA antagonists. Areas covered: This article summarizes the recent findings with the role of miRNAs in lung cancer, and discusses the potential and challenges of developing miRNA-targeted therapeutics in this dreadful disease. Expert opinion: The development of miRNA-targeted therapeutics has become an important anti-cancer strategy. Results from both preclinical and clinical trials of microRNA replacement therapy have shown some promise in cancer treatment. However, some obstacles, including drug delivery, specificity, off-target effect, toxicity mediation, immunological activation and dosage determination should be addressed. Several delivery strategies have been employed, including naked oligonucleotides, liposomes, aptamer-conjugates, nanoparticles and viral vectors. However, delivery remains a main challenge in miRNA-targeting therapeutics. Furthermore, immune-related serious adverse events are also a concern, which indicates the complexity of miRNA-based therapy in clinical settings.

A global view of regulatory networks in lung cancer: An approach to understand homogeneity and heterogeneity

A number of new biotechnologies are used to identify potential biomarkers for the early detection of lung cancer, enabling a personalized therapy to be developed in response. The combinatorial cross-regulation of hundreds of biological function-specific transcription factors (TFs) is defined as the understanding of regulatory networks of molecules within the cell. Here we integrated global databases with 537 patients with lung adenocarcinoma (ADC), 140 with lung squamous carcinoma (SCC), 9 with lung large-cell carcinoma (LCC), 56 with small-cell lung cancer (SCLC), and 590 without cancer with the understanding of TF functions. The present review aims at the homogeneity or heterogeneity of gene expression profiles among subtypes of lung cancer. About 5, 136, 52, or 16 up-regulated or 19, 24, 122, or 97down-regulated type-special TF genes were identified in ADC, SCC, LCC or SCLC, respectively. DNA-binding and transcription regulator activity associated genes play a dominant role in the differentiation of subtypes in lung cancer. Subtype-specific TF gene regulatory networks with elements should be an alternative for diagnostic and therapeutic targets for early identification of lung cancer and can provide insightful clues to etiology and pathogenesis.