MicroRNA-34a inhibits the proliferation and promotes the apoptosis of non-small cell lung cancer H1299 cell line by targeting TGFβR2

The microRNA-34 Family and Its Functional Role in Lung Cancer

Lung cancer is one of the most common malignant tumors in humans and the leading cause of cancer-related deaths worldwide. The microRNA-34 (miR-34) family is dysregulated in various human cancers and is an important family of tumor suppressor genes among microRNAs. The miR-34 family is downregulated in lung cancer. It inhibits cell proliferation, metastasis, and invasion, arrests the cell cycle, and induces apoptosis or senescence by negatively regulating many oncogenes. It is commonly used to detect and treat lung cancer. This study describes the regulatory role of the miR-34 family in lung cancer and the associated research advances in treatment.

Molecular mechanisms underlying the regulation of tumour suppressor genes in lung cancer

Tumour suppressor genes play a cardinal role in the development of a large array of human cancers, including lung cancer, which is one of the most frequently diagnosed cancers worldwide. Therefore, extensive studies have been committed to deciphering the underlying mechanisms of alterations of tumour suppressor genes in governing tumourigenesis, as well as resistance to cancer therapies. In spite of the encouraging clinical outcomes demonstrated by lung cancer patients on initial treatment, the subsequent unresponsiveness to first-line treatments manifested by virtually all the patients is inherently a contentious issue. In light of the aforementioned concerns, this review compiles the current knowledge on the molecular mechanisms of some of the tumour suppressor genes implicated in lung cancer that are either frequently mutated and/or are located on the chromosomal arms having high LOH rates (1p, 3p, 9p, 10q, 13q, and 17p). Our study identifies specific genomic loci prone to LOH, revealing a recurrent pattern in lung cancer cases. These loci, including 3p14.2 (FHIT), 9p21.3 (p16INK4a), 10q23 (PTEN), 17p13 (TP53), exhibit a higher susceptibility to LOH due to environmental factors such as exposure to DNA-damaging agents (carcinogens in cigarette smoke) and genetic factors such as chromosomal instability, genetic mutations, DNA replication errors, and genetic predisposition. Furthermore, this review summarizes the current treatment landscape and advancements for lung cancers, including the challenges and endeavours to overcome it. This review envisages inspired researchers to embark on a journey of discovery to add to the list of what was known in hopes of prompting the development of effective therapeutic strategies for lung cancer.

p53/MicroRNA-34 axis in cancer and beyond

Cancer is serious endangers human life. After a long period of research and accumulation, people's understanding of cancer and the corresponding treatment methods are constantly developing. p53 is an important tumor suppressor gene. With the more in-depth understanding of the structure and function of p53, the more importance of this tumor suppressor gene is realized in the process of inhibiting tumor formation. MicroRNAs (miRNAs) are important regulatory molecules with a length of about 22nucleotides (nt), which belong to non-coding RNA and play an important role in the occurrence and development of tumors. miR-34 is currently considered to be a master regulator of tumor suppression. The positive feedback regulatory network formed by p53 and miR-34 can inhibit the growth and metastasis of tumor cells and inhibit tumor stem cells. This review focuses on the latest progress of p53/miR-34 regulatory network, and discusses its application in tumor diagnosis and treatment.

Indirect co-culture of islet cells in 3D biocompatible collagen/laminin scaffold with angiomiRs transfected mesenchymal stem cells

Diabetes is an autoimmune disease in which the pancreatic islets produce insufficient insulin. One of the treatment strategies is islet isolation, which may damage these cells as they lack vasculature. Biocompatible scaffolds are one of the efficient techniques for dealing with this issue. The current study is aimed to determine the effect of transfected BM-MSCS with angiomiR-126 and -210 on the survival and functionality of islets loaded into a 3D scaffold via laminin (LMN). AngiomiRs/Poly Ethylenimine polyplexes were transfected into bone marrow-mesenchymal stem cells (BM-MSCs), followed by 3-day indirect co-culturing with islets laden in collagen (Col)-based hydrogel scaffolds containing LMN. Islet proliferation and viability were significantly increased in LMN-containing scaffolds, particularly in the miRNA-126 treated group. Insulin gene expression was superior in Col scaffolds, especially, in the BM-MSCs/miRNA-126 treated group. VEGF was upregulated in the LMN-containing scaffolds in both miRNA-treated groups, specifically in the miRNA-210, leading to VEGF secretion. MiRNAs' target genes showed no downregulation in LMN-free scaffolds; while a drastic downregulation was seen in the LMN-containing scaffolds. The highest insulin secretion was recorded in the Oxidized dextran (Odex)/Col^LMN+ group with miRNA-126. LMN-containing biocompatible scaffolds, once combined with angiomiRs and their downstream effectors, promote islets survival and restore function, leading to enhanced angiogenesis and glycemic status.

Hsa_circ_0000520 Promotes Non-Small Cell Lung Cancer Progression through the miR-1258/AKT3 Axis

Background

There are several previous studies suggesting that circular RNAs (circRNAs) are involved in tumorigenesis of non-small cell lung cancer (NSCLC). Nevertheless, the role of circRNA_0000520 (circ_0000520) in this disease has not yet been studied.

Methods

circ_0000520, microRNA (miR)-1258, and AKT serine/threonine kinase 3 (AKT3) mRNA expression levels were detected by qPCR. CCK-8, EdU, and Transwell assays were utilized to detect NSCLC cells' malignant biological behaviors. The targeted relationship between miR-1258 and AKT3 3'-UTR or circ_0000520 was verified through the dual-luciferase reporter gene assay. Western blotting was utilized to measure the AKT3 expression after circ_0000520 and miR-1258 were selectively regulated.

Results

circ_0000520 was upregulated in NSCLC. Highly expressed circ_0000520 is linked to the NSCLC patient's advanced TNM stage and lymph node metastasis. circ_0000520 overexpression facilitated NSCLC cell growth, migration, and invasion. miR-1258 was identified as the downstream target of circ_0000520. miR-1258 overexpression weakened the effect of circ_0000520 overexpression on NSCLC cells. miR-1258 targeted and inhibited AKT3. circ_0000520 positively regulated the AKT3 expression in NSCLC cells by sponging miR-1258.

Conclusion

circ_0000520 upregulates AKT3 by competitively binding with miR-1258 to facilitate NSCLC progression.

LINC00511 promotes cervical cancer progression by regulating the miR-497-5p/MAPK1 axis

BACKGROUND

Long non-coding RNA (lncRNA) exhibits a crucial role in multiple human malignancies. The expression of lncRNA LINC00511, reportedly, is aberrantly up-regulated in several types of tumors. Our research was aimed at deciphering the role and mechanism of LINC00511 in the progression of cervical cancer (CC).

METHOD

Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to quantify the expression levels of LINC00511, miR-497-5p and MAPK1 mRNA in CC tissues and cell lines. Cell counting kit-8 (CCK-8), 5-bromo-2'-deoxyuridine (BrdU) and Transwell assays were conducted for detecting the proliferation, migration and invasion of CC cells. Dual-luciferase reporter gene experiments were performed to verify the targeting relationships amongst LINC00511, miR-497-5p and MAPK1. Besides, MAPK1 expression in CC cells was detected via Western blot after LINC00511 and miR-497-5p were selectively regulated.

RESULTS

Up-regulation of LINC00511 expression in CC tissues and cell lines was observed, which was in association with tumor size, clinical stage and lymph node metastasis of the patients. LINC00511 overexpression facilitated the proliferation, migration and invasion of CC cells, while opposite effects were observed after knockdown of LINC00511. Mechanistically, LINC00511 was capable of targeting miR-497-5p and up-regulating MAPK1 expression.

CONCLUSION

LINC00511/miR-497-5p/MAPK1 axis regulates CC progression.

Functions of non-coding RNAs in regulating cancer drug targets

With the development of precision medicine, the efficiency of tumor treatment has been significantly improved. More attention has been paid to targeted therapy and immunotherapy as the key to precision treatment of cancer. Targeting epidermal growth factor receptor (EGFR) has become one of the most important targeted treatments for various cancers. Comparing with traditional chemotherapy drugs, targeting EGFR is highly selective in killing tumor cells with better safety, tolerability and less side effect. In addition, tumor immunotherapy has become the fourth largest tumor therapy after surgery, radiotherapy and chemotherapy, especially immune checkpoint inhibitors. However, these treatments still produce a certain degree of drug resistance. Non-coding RNAs (ncRNAs) were found to play a key role in carcinogenesis, treatment and regulation of the efficacy of anticancer drugs in the past few years. Therefore, in this review, we aim to summarize the targeted treatment of cancers and the functions of ncRNAs in cancer treatment.

A deep learning approach to predict inter-omics interactions in multi-layer networks

Background

Despite enormous achievements in the production of high-throughput datasets, constructing comprehensive maps of interactions remains a major challenge. Lack of sufficient experimental evidence on interactions is more significant for heterogeneous molecular types. Hence, developing strategies to predict inter-omics connections is essential to construct holistic maps of disease.

Results

Here, as a novel nonlinear deep learning method, Data Integration with Deep Learning (DIDL) was proposed to predict inter-omics interactions. It consisted of an encoder that performs automatic feature extraction for biomolecules according to existing interactions coupled with a predictor that predicts unforeseen interactions. Applicability of DIDL was assessed on different networks, namely drug–target protein, transcription factor-DNA element, and miRNA–mRNA. Also, validity of the novel predictions was evaluated by literature surveys. According to the results, the DIDL outperformed state-of-the-art methods. For all three networks, the areas under the curve and the precision–recall curve exceeded 0.85 and 0.83, respectively.

Conclusions

DIDL offers several advantages like automatic feature extraction from raw data, end-to-end training, and robustness to network sparsity. In addition, reliance solely on existing inter-layer interactions and independence of biochemical features of interacting molecules make this algorithm applicable for a wide variety of networks. DIDL paves the way to understand the underlying mechanisms of complex disorders through constructing integrative networks.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12859-022-04569-2.

The role of microRNAs in COVID-19 with a focus on miR-200c

Objective:

Epigenetics is a quickly spreading scientific field, and the study of epigenetic regulation in various diseases such as infectious diseases is emerging. The microribonucleic acids (miRNAs) as one of the types of epigenetic processes bind to their target messenger RNAs (mRNAs) and regulate their stability and/or translation. This study aims to evaluate non-coding RNAs (ncRNAs) with a focus on miR-200c in COVID-19. In this review, we first define the epigenetics and miRNAs, and then the role of miRNAs in diseases focusing on lung diseases is explained. Finally, in this study, we will investigate the role and position of miRNAs with a focus on miR-200c in viral and severe acute respiratory syndrome–related coronavirus (SARS-CoV2) infections.

Methods:

Systematic search of MEDLINE, PubMed, Web of Science, Embase, and Cochrane Library was conducted for all relative papers from 2000 to 2021 with the limitations of the English language. Finally, we selected 128 articles which fit the best to our objective of study, among which 5 articles focused on the impact of miR-200c.

Results:

Due to the therapeutic results of various drugs in different races and populations, epigenetic processes, especially miRNAs, are important. The overall results showed that different types of miRNAs can be effective on the process of various lung diseases through different target pathways and genes. It is likely that amplified levels of miR-200c may lead to decreased angiotensin-converting enzyme-2 (ACE2) expression, which in turn may increase the potential of infection, inflammation, and the complications of coronavirus disease.

Conclusion:

miR-200c and its correlation with ACE2 can be used as early prognostic and diagnostic markers.

Characterization of miR-34a-Induced Epithelial-Mesenchymal Transition in Non-Small Lung Cancer Cells Focusing on p53

Background: Epithelial–mesenchymal transition (EMT), a phenotypic conversion of the epithelial to mesenchymal state, contributes to cancer progression. Currently, several microRNAs (miRNAs) are associated with EMT-mediated cancer progression, but the contribution of miR-34a to EMT in cancer cells remains controversial. The present study aimed to clarify the role of miR-34a in the EMT-related phenotypes of human non-small cell lung cancer (NSCLC) cell lines, A549 (p53 wild-type) and H1299 (p53-deficient). Methods: The miR-34a mimic and p53 small interfering RNA (siRNA) were transfected into the cells using Lipofectamine, and the obtained total RNA and cell lysates were used for real-time polymerase chain reaction and Western blotting analysis, respectively. Results: The introduction of the miR-34a mimic led to an increase in the mRNA and protein expression levels of α-smooth muscle actin (α-SMA), a mesenchymal marker gene, in A549, but not in H1299 cells. Additionally, miR-34a-induced the upregulation of p53 activity and migration was observed in A549, but not in H1299 cells. However, under the p53-knockdown condition, only α-SMA upregulation by miR-34a was abolished. Conclusion: These findings indicate a close relationship between p53 and miR-34a-induced EMT in p53-wild type NSCLC cells, which provides novel insights about the role of miR-34a in EMT-like phenotypic changes in NSCLC.

Bioinformatics analysis reveals a stem cell-expressed circ-Serpine2-mediated miRNA-mRNA regulatory subnetwork in the malignant progression of glioma

Background

High-grade glioma has a poor prognosis, and GSCs can have pivotal roles in glioma pathology. This study investigated GSC exosome-containing circRNA mechanisms affecting the malignant progression of glioma.

Methods

In this study, we identified differentially expressed circRNAs and constructed a circRNA-miRNA-mRNA regulatory network through circRNA sequencing/bioinformatics analysis. Then, we identified circRNAs that were upregulated in GSC23 cells and employed them as downstream targets in subsequent investigations. Such investigations included downstream target knockout to assess any influence on A172 cell proliferation, invasion, migration and apoptosis. In addition, in vivo investigations using tumor-bearing animals evaluated the in vivo influences of the selected targets.

Results

This study identified circ-Serpine2/miR-124-3p/KIF20A as a regulatory pathway in glioma. Our in vitro analysis confirmed that circ-Serpine2 could upregulate KIF20A by sponging miR-124-3p, consequently promoting A172 cell proliferation, migration and invasion. Such a signaling channel could also inhibit glioma cell apoptosis. Additionally, our research indicated that circ-Serpine2 inhibited glioma apoptosis and promoted in vivo tumor progression.

Conclusion

Circ-Serpine2 exacerbated the malignant progression of glioma mediated by the miR-124-3p/KIF20A nexus, thus providing novel predictive/prognostic biomarkers and drug targets against glioma.

tRNA-derived fragments as New Hallmarks of Aging and Age-related Diseases

tRNA-derived fragments (tRFs), which are non-coding RNAs produced via tRNA cleavage with lengths of 14 to 50 nucleotides, originate from precursor tRNAs or mature tRNAs and exist in a wide range of organisms. tRFs are produced not by random fracture of tRNAs but by specific mechanisms. Considerable evidence shows that tRFs are detectable in model organisms of different ages and are associated with age-related diseases in humans, such as cancer and neurodegenerative diseases. In this literature review, the origin and classification of tRFs and the regulatory mechanisms of tRFs in aging and age-related diseases are summarized. We also describe the available tRF databases and research techniques and lay a foundation for the exploration of tRFs as biomarkers for the diagnosis and treatment of aging and age-related diseases.

MicroRNAs: Key Regulators in Lung Cancer

Noncoding RNAs have emerged as key regulators of the genome upon gene expression profiling and genome-wide sequencing. Among these noncoding RNAs, microRNAs are short noncoding RNAs that regulate a plethora of functions, biological processes and human diseases by targeting the messenger RNA stability through 3'UTR binding, leading to either mRNA cleavage or translation repression, depending on microRNA-mRNA complementarity degree. Additionally, strong evidence has suggested that dysregulation of miRNAs contribute to the etiology and progression of human cancers, such as lung cancer, the most common and deadliest cancer worldwide. Indeed, by acting as oncogenes or tumor suppressors, microRNAs control all aspects of lung cancer malignancy, including cell proliferation, survival, migration, invasion, angiogenesis, cancer stem cells, immune-surveillance escape, and therapy resistance; and their expressions are often associated with clinical parameters. Moreover, several deregulated microRNAs in lung cancer are carried by exosomes, microvesicles and secreted in body fluids, mainly the circulation where they conserve their stable forms. Subsequently, seminal efforts have been focused on extracellular microRNAs levels as noninvasive diagnostic and prognostic biomarkers in lung cancer. In this review, focusing on recent literature, we summarize the deregulation, mechanisms of action, functions and highlight clinical applications of miRNAs for better management and design of future lung cancer targeted therapies.

MicroRNA-486-5p Suppresses Lung Cancer via Downregulating mTOR Signaling In Vitro and In Vivo

Lung cancer is one of the central causes of tumor-related deaths globally, of which non-small cell lung cancer (NSCLC) takes up about 85%. As key regulators of various biological processes, microRNAs (miRNAs) have been verified as crucial factors in NSCLC. To elucidate the role of miR-486-5p in the mTOR pathway, we investigated its role in NSCLC and related signaling. Our results confirmed that miR-486-5p was downregulated in most of human NSCLC tissue samples and cell lines. Further study confirmed that it inhibited NSCLC through repression of the mTOR pathway via targeting both ribosomal proteins S6 kinase A1 (RPS6KA1, RSK) and ribosomal proteins S6 kinase B1 (RPS6KB1, p70S6K), which are critical components of the mTOR signaling. Additionally, miR-486-5p impeded tumor growth in vivo and inhibited tumor metastasis through repression of the epithelial-mesenchymal transition (EMT). Taken together, our study verified the role that miR-486-5p exerts in NSCLC, and its expression pattern in the different stages and morphologies of NSCLC makes it a promising biomarker in the early diagnosis of the disease.

Extracellular vesicle-encapsulated microRNA-23a from dorsal root ganglia neurons binds to A20 and promotes inflammatory macrophage polarization following peripheral nerve injury

Extracellular vesicles (EVs) are capable of transferring microRNAs (miRNAs or miRs) between two different types of cells and also serve as vehicles for delivery of therapeutic molecules. After peripheral nerve injury, abnormal expression patterns of miRNAs have been observed in dorsal root ganglia (DRG) sensory neurons. We hypothesized that sensory neurons secrete miRs-containing EVs to communicate with macrophages. We demonstrated that miR-23a was upregulated in DRG neurons in spared nerve injury (SNI) mouse models. We also found that miR-23a was enriched in EVs released by cultured DRG neurons following capsaicin treatment. miR-23a-containing EVs were taken up into macrophages in which increased intracellular miR-23a promoted pro-inflammatory phenotype. A20 was verified as a target gene of miR-23a. Moreover, intrathecal delivery of EVs-miR-23a antagomir attenuated neuropathic hypersensitivity and reduced the number of M1 macrophages in injured DRGs by targeting A20. In conclusion, these results demonstrate that sensory neurons transfer EVs-encapsulated miR-23a to activate M1 macrophages and enhance neuropathic pain following the peripheral nerve injury. The study highlighted a new therapeutic approach to alleviate chronic neuropathic pain after nerve trauma by targeting detrimental miRNA in sensory neurons.

A promising effect of zerumbone with improved anti-tumor-promoting inflammation activity of miR-34a in colorectal cancer cell lines

Cross-talk among inflammation and colorectal cancer cells is chiefly reported through a complex of cytokines, chemokines, and growth factors. MicroRNA performs strategic roles in controlling a variety of signaling cascades. miR-34a is known as a master regulator of tumor suppression. Combined application of different miRNA-based agents and chemotherapeutic drugs has been used to augment drug sensitivity and may reinforce the antitumor effect. A lot of studies specify a substantial increase in the effectiveness of combination therapies. The anti-inflammatory activity of Zerumbone (ZER) was investigated in many cancers. In this study the level of the inflammatory cytokines including CXCL-12 (SDF-1), CCL-2 (MCP-1), TGF-β and IL-33 has been measured in pmiR-34a-5p transfected and pmiR-34a-5p +ZER treated CRC cell lines (HCT-116 and SW48) by QRT-PCR and ELISA methods, respectively. The results showed that miR-34a could significantly inhibit cytokine expression in both cell lines for 48 and 72 h except SDF-1 which no inhibition was observed in SW48 cells. ZER suppressed SDF-1 for all three time points in both cell lines, while in SW48 cells IL-33 and TGF-β were inhibited in 72 h and in HCT-116 cells MCP-1 diminished for only 24 h and TGF-β diminished for all three times. Combination of both miR-34a and ZER suppressed TGF-β, SDF-1 and MCP-1 in HCT-116 cells in all time points while in SW48 cells, suppression of most cytokines was observed in 48 and 72 h. Furthermore Colony formation assay and scratch test were employed to detect changes of proliferation and migration in CRC transfected and treated cells. Generally, we found that miR-34a could considerably decrease the expression of inflammatory cytokines and the combination of ZER+ miR-34 boosted this effect. Moreover the migration and proliferation decreased in treated and transfected cells and this reduction was more severe in miR-34a +ZER treatment. It is important to note that in the case of cell resistance to each of these therapeutic agents, inhibition of cytokines can be compensated by another one.

Exosomes from microRNA-126 overexpressing mesenchymal stem cells promote angiogenesis by targeting the PIK3R2-mediated PI3K/Akt signalling pathway

microRNA‐126 (miR‐126), an endothelial‐specific miRNA, is associated with vascular homeostasis and angiogenesis. However, the efficiency of miR‐126‐based treatment is partially compromised due to the low efficiency of miRNA delivery in vivo. Lately, exosomes have emerged as a natural tool for therapeutic molecule delivery. Herein, we investigated whether exosomes derived from bone marrow mesenchymal stem cells (BMMSCs) can be utilized to deliver miR‐126 to promote angiogenesis. Exosomes were isolated from BMMSCs overexpressed with miR‐126 (Exo‐miR‐126) by ultracentrifugation. In vitro study, Exo‐miR‐126 treatment promoted the proliferation, migration and angiogenesis of human umbilical vein endothelial cells (HUVECs). Furthermore, the gene/protein expression of angiogenesis‐related vascular endothelial growth factor (VEGF) and angiotensin‐1 (Ang‐1) were up‐regulated after incubation with Exo‐miR‐126. Additionally, the expression level of phosphoinositol‐3 kinase regulatory subunit 2 (PIK3R2) showed an inverse correlation with miR‐126 in HUVECs. Particularly, the Exo‐miR‐126 treatment contributed to enhanced angiogenesis of HUVECs by targeting PIK3R2 to activate the PI3K/Akt signalling pathway. Similarly, Exo‐miR‐126 administration profoundly increased the number of newly formed capillaries in wound sites and accelerated the wound healing in vivo. The results demonstrate that exosomes derived from BMMSCs combined with miR‐126 may be a promising strategy to promote angiogenesis.

Long non-coding RNA XIST binding to let-7c-5p contributes to rheumatoid arthritis through its effects on proliferation and differentiation of osteoblasts via regulation of STAT3

BACKGROUND

Rheumatoid arthritis (RA), a chronic autoimmune disease, affects around 1% population worldwide, with the life quality of patients severely reduced. In this study, it is intended to explore the role of long non-coding RNA X-inactive specific transcript (lncRNA XIST) in RA and the underlying mechanisms associated with let-7c-5p and signal transducer and activator of transcription 3 (STAT3).

METHODS

LncRNA XIST, let-7c-5p, and STAT3 expressions were determined in RA and normal cartilage tissues, and their relationship was analyzed in osteoblasts. The regulatory effects of lncRNA XIST in RA were investigated when XIST expression was upregulated or downregulated in osteoblasts. TNF-α, IL-2, IL-6, alkaline phosphatase (ALP), osteocalcin, TGF-β1, and IGF1 were measured in vivo in RA rats.

RESULTS

LncRNA XIST and STAT3 were expressed at high levels and let-7c-5p expressed at a low level in RA cartilage tissues. LncRNA XIST silencing or let-7c-5p enhancement led to decreased levels of TNF-α, IL-2, and IL-6, suggestive of suppressed inflammatory response, and increased levels of ALP, osteocalcin, TGF-β1, and IGF-1 as well as reduced damage in cartilage tissues.

CONCLUSION

LncRNA XIST downregulation could promote proliferation and differentiation of osteoblasts in RA, serving as a future therapeutic target for RA.

Distinct prognostic values and antitumor effects of tumor growth factor β1 and its receptors in gastric cancer

Gastric cancer (GC) is one of the most common malignancies and is the second leading cause of cancer-associated mortality world-wide. In the present study, the prognostic value and antitumor effects of transforming growth factor β1 (TGFβ1) and its receptors in GC were explored. The online Kaplan-Meier plotter database was used to investigate the prognostic values of TGFβ1 and its receptors. The present study demonstrated that low mRNA expression levels of TGFβ1 and its 3 receptors, transforming growth factor β1 (TGFβR1), TGFβR2 and TGFβR3, was associated with improved overall survival time in patients with GC. Cell Counting Kit-8 and Transwell assays were used to confirm the effects of TGFβ1, TGFβR1, TGFβR2 and TGFβR3 on the proliferation, migration and invasiveness of the AGS and MKN45 GC cell lines. It was found that the knockdown of these genes blocked cell proliferation, migration and invasion in GC cells. To the best of our knowledge, the present study is the first to determine the role of TGFβR1 and TGFβR3 in GC cells. The results indicate that in addition to TGFβ1 and TGFβR2, TGFβR1 also plays a specific role in the occurrence and development of tumors. Thus, these markers may be considered as potential prognostic indicators in human GC. The findings of the present study indicate that not only TGFβ1 and TGFβR2, but also TGFβR1 is involved in the progression of GC. The findings of the present study provide new ideas and approaches for the treatment of patients with GC.

Higher expression of miR-150-5p promotes tumorigenesis by suppressing LKB1 in non-small cell lung cancer

Lung cancer is one of the most malignant tumors that can form in the human. MicroRNAs (MiRNAs) play significant role in tumor progression. Human lung cancer tissues and cell lines were used to determine miR-150-5p respectively, and Liver Kinase B1 (LKB1) expression using quantitative real-time PCR (qRT-PCR). The data analysis website Kaplan-Meier Plotter (database obtained from The Cancer Genome Atlas) was used to perform a survival analysis with LKB1 levels. Using the appropriate assays, the function of miR-150-5p was also detected in cellular proliferation, migration and cell apoptosis as well as cell cycle. Results revealed that miR-150-5p was upregulated in non-small cell lung cancer (NSCLC) tissue and cell lines. In NSCLC, miR-150-5p promoted cellular proliferation and migration, but decreased cellular apoptosis. Conversely, miR-150-5p inhibition suppressed cellular growth. These results further revealed a network of cellular signaling for miR-150-5p to target LKB1. Ectopic expression of LKB1 can mitigate the tumor-promoting function of miR-150-5p. Collectively, these results indicated that miR-150-5p may promote lung cancer by inhibiting the suppressor gene LKB1 in NSCLC.

Circ-TCF4.85 silencing inhibits cancer progression through microRNA-486-5p-targeted inhibition of ABCF2 in hepatocellular carcinoma

The current study aimed to explore the role of the circular RNA circ‐TCF4.85 and its downstream target microRNA‐486‐5p (miR‐486‐5p) in hepatocellular carcinoma (HCC) development. Circ‐TCF4.85 was detected to be highly expressed in HCC tissues. Next, we found that silencing of circ‐TCF4.85 repressed HCC cell proliferation, invasion, and migration, while enhancing apoptosis. In addition, biotin‐coupled probe pull‐down and miRNA capture assays, as well as fluorescence in situ hybridization, confirmed that circ‐TCF4.85 could bind to miR‐486‐5p. In rescue experiments, miR‐486‐5p had the potential to eliminate the tumor‐suppressive effects of circ‐TCF4.85 knockdown in HCC. Moreover, miR‐486‐5p was shown to target ABCF2 gene, which was positively regulated by circ‐TCF4.85. Finally, nude mice subcutaneously injected with si‐circ‐TCF4.85‐transfected HCC cells presented with inhibited xenograft tumor formation in vivo. Taken together, our results reveal that silencing of circ‐TCF4.85 suppresses HCC progression via miR‐486‐5p‐targeted inhibition of ABCF2.

MicroRNAs in non-small cell lung cancer: Gene regulation, impact on cancer cellular processes, and therapeutic potential

Lung cancer remains the most lethal cancer among men and women in the United States and worldwide. The majority of lung cancer cases are classified as non-small cell lung cancer (NSCLC). Developing new therapeutics on the basis of better understanding of NSCLC biology is critical to improve the treatment of NSCLC. MicroRNAs (miRNAs or miRs) are a superfamily of genome-derived, small noncoding RNAs that govern posttranscriptional gene expression in cells. Functional miRNAs are commonly dysregulated in NSCLC, caused by genomic deletion, methylation, or altered processing, which may lead to the changes of many cancer-related pathways and processes, such as growth and death signaling, metabolism, angiogenesis, cell cycle, and epithelial to mesenchymal transition, as well as sensitivity to current therapies. With the understanding of miRNA biology in NSCLC, there are growing interests in developing new therapeutic strategies, namely restoration of tumor suppressive miRNAs and inhibition of tumor promotive miRNAs, to combat against NSCLC. In this article, we provide an overview on the molecular features of NSCLC and current treatment options with a focus on pharmacotherapy and personalized medicine. By illustrating the roles of miRNAs in the control of NSCLC tumorigenesis and progression, we highlight the latest efforts in assessing miRNA-based therapies in animal models and discuss some critical challenges in developing RNA therapeutics.

Downregulation of oncogenic gene TGFβR2 by miRNA-107 suppresses non-small cell lung cancer

Non-small cell lung cancer (NSCLC) accounts for more than 80% of lung cancer cases with a low 5-year survival rate. MicroRNA may be targeted in the clinical treatment of the disease. In this study, miR-107 showed low expression in NSCLC serum samples, and it could suppress cell proliferation, migration and arrest cell cycle in NSCLC cell lines. Results revealed that miR-107 could inhibit the expression of transforming growth factor β receptor 2 (TGFβR2) via targeting TGFβR2. Downregulation of TGFβR2 also suppressed cell proliferation, migration and cell cycle in NSCLC cell lines. Our data suggested that miR-107 could inhibit the progression of NSCLC by targeting TGFβR2.

Correlative analysis of miR-34b and p53 with pathological characteristics of NSCLC

The expression of miR-34b and p53 in non-small cell lung cancer (NSCLC) was investigated to explore its relationship with clinical pathology of NSCLC. Reverse transcription-quantitative PCR (RT-qPCR) method was used to quantitatively analyze miR-34b and p53 in cancer tissue and adjacent paraneoplastic (PTLC) tissue in 54 cases of NSCLC. The relationship between gene expression and clinical pathological data was analyzed. The expression of miR-34b in tumor tissues of NSCLC patients was significantly downregulated in comparison with PTLC. The expression level of miR-34b was negatively correlated with lymph node metastasis. It was positively correlated with the degree of differentiation and negatively correlated with the pathological stage (P<0.05). There was no significant association in the expression of miR-34b with age, sex, histological type, and gross classification (all P>0.05). The expression of p53 in the tumor tissue of NSCLC patients was significantly reduced in comparison with PTLC, and its expression was negatively correlated with the pathological stage, lymph node metastasis, and was positively correlated with the degree of differentiation. The expression of p53 in adenocarcinoma was generally higher than that of squamous cell carcinoma and large cell carcinoma. The expression of p53 in central type cancer was significantly higher than that in peripheral type (P<0.05). The expression of miR-34b and p53 was positively correlated in NSCLC tissues (r=0.797, P<0.001). The high expression of miR-34b and p53 is closely related to the clinical stage and pathological grade of NSCLC. miR-34b and p53 may serve as important tumor markers for NSCLC.

Exosomes derived from microRNA-101-3p-overexpressing human bone marrow mesenchymal stem cells suppress oral cancer cell proliferation, invasion, and migration

Dysregulation of microRNAs (miRNAs) has been found to disrupt the progression of oral cancer. However, which miRNAs are most effective against oral cancer and how these miRNAs should be delivered are major unanswered problems. We aimed at investigating if human bone marrow mesenchymal stem cells (hBMSCs)-derived exosomes affect oral cancer development, and the potential regulatory mechanism associated with COL10A1 and miR-101-3p. COL10A1 was upregulated, while miR-101-3p was downregulated in oral cancer, and miR-101-3p targeted COL10A1 as verified by dual-luciferase reporter gene assay. Meanwhile, exosomes derived from hBMSCs were isolated and then co-cultured with oral cancer cells to identify the role of exosomes, and the results suggested that hBMSCs-derived exosomes overexpressing miR-101-3p inhibited oral cancer progression. Furthermore, tumorigenicity assay in nude mice further confirmed the inhibitory effects of hBMSCs-derived exosomes, loaded with miR-101-3p, on oral cancer, which provides a new theoretical basis in the treatment of oral cancer.

microRNA-301b-3p downregulation underlies a novel inhibitory role of long non-coding RNA MBNL1-AS1 in non-small cell lung cancer

BACKGROUND

Non-small cell lung cancer (NSCLC) is the second most prevalent cause of cancer-related fatality. Long non-coding RNAs (lncRNAs) have been observed to exercise functions in NSCLC. Here, the current study aimed to explore the potential mechanism of lncRNA MBNL1-AS1 in NSCLC.

METHODS

Microarray analysis was performed to screen the differentially expressed lncRNA associated with NSCLC and its potential mechanism. The lncRNA MBNL1-AS1 expression was quantified in 56 paired NSCLC and adjacent normal tissue samples. In an attempt to outline the function of lncRNA MBNL1-AS1 in NSCLC and to identify the interaction among lncRNA MBNL1-AS1, microRNA-301b-3p (miR-301b-3p) and TGFBR2, ectopic expression, depletion, and reporter assay experiments were conducted to detect CSC proliferation, migration, invasion, drug resistance, and sphere formation in NSCLC.

RESULTS

Initially, the intersection among lncRNA MBNL1-AS1, miR-301b-3p, and TGFBR2 was observed in NSCLC. While a poor expression of lncRNA MBNL1-AS1 and TGFBR2, along with a high expression of miR-301b-3p was observed in NSCLC tissues. A demonstration of lncRNA MBNL1-AS1 restoration significantly decreased CSC proliferation, migration, invasion, drug resistance, and sphere formation in NSCLC. LncRNA MBNL1-AS1 functioned as a sponge of miR-301b-3p, which inverted the inhibitory role of lncRNA MBNL1-AS1 in CSC proliferation, migration, invasion, drug resistance, and sphere formation in NSCLC. LncRNA MBNL1-AS1 positively regulated TGFBR2 which was a target gene of miR-301b-3p. At last, upregulated lncRNA MBNL1-AS1 or depleted miR-301b-3p suppressed the xenograft tumor formation in vivo.

CONCLUSION

Collectively, the present study suggests an inhibitory role of lncRNA MBNL1-AS1 in CSC drug resistance of NSCLC by upregulating miR-301b-3p-targeted TGFBR2.

Glioma stem cells-derived exosomal miR-26a promotes angiogenesis of microvessel endothelial cells in glioma

BACKGROUND

Cancer stem cells (CSCs), which are involved in cancer initiation and metastasis, could potentially release exosomes that mediate cellular communication by delivering microRNAs (miRNAs). Based on the role of miR-26a in angiogenesis of glioma, our study was performed to investigate whether glioma stem cells (GSCs)-derived exosomes containing miR-26a could exert effects on angiogenesis of microvessel endothelial cells in glioma, in order to provide a new therapeutic RNA vehicle for glioma therapies.

METHODS

The expression of miR-26a and PTEN in glioma was quantified and the interaction among miR-26a, PTEN and PI3K/Akt signaling pathway was examined. Next, a series of gain- and loss-of function experiments were conducted to determine the role of miR-26a in angiogenesis of human brain microvascular endothelial cells (HBMECs). Subsequently, HBMECs were exposed to exosomes derived from GSCs with the gain-/loss-of-function of miR-26a. Finally, the effect of exosomal miR-26a on angiogenesis of HBMECs was assessed both in vitro and in vivo.

RESULTS

The results revealed that PTEN was down-regulated, while miR-26a was up-regulated in glioma. miR-26a activated the PI3K/Akt signaling pathway by targeting PTEN. Restored miR-26a promoted proliferation, migration, tube formation, and angiogenesis of HBMECs in vitro. In addition, GSCs-derived exosomes overexpressing miR-26a contributed to enhanced proliferation and angiogenesis of HBMECs in vitro through inhibition of PTEN. The angiogenic effects of GSCs-derived exosomes overexpressing miR-26a in vivo were consistent with the above-mentioned in vitro findings.

CONCLUSION

Collectively, our study demonstrates that GSCs-derived exosomal miR-26a promotes angiogenesis of HBMECs, highlighting an angiogenic role of miR-26a via exosomes.

RETRACTED: MicroRNA-34 suppresses proliferation of human ovarian cancer cells by triggering autophagy and apoptosis and inhibits cell invasion by targeting Notch 1

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editors. The substance of the retraction is as follows: Attention has been drawn by Dr Elisabeth Bik to the fact that similar images representing the results of different experiments are shown in Figures 1G and 3F. She also points to the remarkable similarity between the legend text and line graphs of Figure 1 of the Biochimie article, Jia et al (2019), and Figure 1 of a publication in Eur Rev Med Pharmacol Sci (2019), Xu et al (2019). The latter article has since been retracted. An anomymous reader has observed that Figures 1G and 3F show three rows of images shared with Figure 4 of the first-published version of a manuscript in the Journal of the Balkan Union of Oncology (J BUON), Tan et al (2019), submitted and accepted for publication before the submission of the Biochimie article, though it has since publication undergone unexplained modification to Figure 4. Furthermore, the panels shared between the Biochimie and J BUON articles are similar to panels in Figure 7 of a much earlier manuscript, published in October 2017 in Science Reports (Dai et al), as well as to a figure in a later article, Li et al (2020). In addition, the top panel of Figure 3G in Jia et al (2019) as well as the two lower panels is also similar to a part of Figure 7, Dia et al (2017). Further unexplained anomalies concern Figure 3C of Jia et al (2019). The editors would like to thank Dr Bik and the anonymous reader for their valuable insight in this matter. The above observations cast serious doubt on the scientific integrity of the Biochimie article. Confronted with the observation that panels in Figures 1G and 3F were similar though representing different experiments, the authors replied to the editors that the bottom panel in Figure 3F was a mistake and would be corrected. They were not able to produce the raw data when requested, and proposed to the editors to repeat the experiments. However, no new data have been received by the editors at the time of writing, and would not change the serious doubts that they harbour concerning the integrity of the work published in Biochimie. Therefore, the editorial team has opted for retraction irrespective of any new results. This decision has been accepted by the authors.

Rapamycin- and starvation-induced autophagy are associated with miRNA dysregulation in A549 cells

MicroRNAs (miRNAs) are short (20-23 nt) non-coding RNAs that are involved in post-transcriptional regulation of gene expression in multicellular organisms by affecting both the stability and translation of mRNAs. In recent years, deep sequencing of the transcription is being increasingly utilized with the promise of higher sensitivity for the identification of differential expression patterns as well as the opportunity to discover new transcripts, including new alternative isoforms and miRNAs. In this study, miRNAs from A549 cells treated with/without rapamycin or starvation were subject to genome-wide deep sequencing. A total of 1534 miRNAs were detected from the rapamycin- and starvation-treated A549 cells. Among them, 31 miRNAs were consistently upregulated and 131 miRNAs were downregulated in the treated cells when compared with the untreated cells. Gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis of the predicted target genes of the most significantly differentially expressed miRNAs revealed that the autophagy-related miRNAs are involved in cancer pathway. Taken together, our findings indicate that the underlying mechanism responsible for autophagy is associated with dysregulation of miRNAs in rapamycin- or starvation-induced A549 cells.

Association of miR-34a Expression with Quality of Life of Glioblastoma Patients: A Prospective Study

MiR-34a acts as tumor-suppressor by targeting many oncogenes related to proliferation, apoptosis, and invasion of gliomas. We studied the relationships between health-related quality of life (HRQOL), depression, and miR-34a expression status in patients with newly diagnosed glioblastoma (GBM). A comprehensive HRQOL assessment was completed by 38 patients with glioblastoma prior to surgical resection and included the European Organization for Research and Treatment of Cancer (EORTC) questionnaire for cancer patients (QLQ-C30) and the Brain Cancer-Specific Quality of Life Questionnaire (QLQ-BN20), the Patient Health Questionnaire-9 (PHQ-9), the Karnofsky performance index (KPS), and The Glasgow Outcome Scale (GOS). The miR-34a expression in glioblastoma tissue was measured using quantitative reverse transcription PCR. Our findings show that lower miR-34a expression is significantly associated with higher tumor volume, worse physical functioning, lower KPS, and greater depressive symptom severity of GBM patients. Moreover, analysis reveals that miR-34a effects might be gender specific, as stronger relationships between miR-34a and patient functioning measures were observed in males when compared to females. Despite the fact that, due to small sample size, our results should be considered as preliminary, our study suggests that miR-34a is associated with tumor burden and can be important for health-related quality of life, functional status, and mood symptoms of glioblastoma patients.

Upregulated circular RNA circ_0074027 promotes glioblastoma cell growth and invasion by regulating miR-518a-5p/IL17RD signaling pathway

Glioblastoma (GBM) is one of the major cause of the cancer-related fatality worldwide. Several circular RNAs (circRNAs) have been observed to exert functions in GBM. The current study is aimed to explore the potential mechanism of circ_0074027 via miR-518a-5p and IL17RD in GBM progression. Circ_0074027 expression was determined in a cohort of 50 pairs of GBM specimens and five cell lines by qRT-PCR. In addition, the association between circ_0074027 expression and its clinical value was analyzed by Fisher's exact test. Cell growth, clone formation, apoptosis, migration and invasion was evaluated after overexpress or knockdown the expression of circ_0074027 in GBM cells. Dual luciferase reporter assays were conducted to evaluate the relevant intermolecular target relationships. Circ_0074027 expression was evidently upregulated in GBM tissue specimens and cells compared to the adjacent non-tumorous tissues and NHA, respectively. The upregulation of circ_0074027 is related to clinical severity and exerts oncogenic functions in GBM. Moreover, circ_0074027 could sponge miR-518a-5p to release its suppression on IL17RD. Our findings provide evidence that circ_0074027 plays an oncogenic role in GBM by regulating miR-518a-5p/IL17RD signaling.

MicroRNA-296-5p promotes healing of diabetic wound by targeting sodium-glucose transporter 2 (SGLT2)

BACKGROUND

Diabetic wounds are refractory and very difficult to heal. We aimed to use miRNA to identify novel and specific molecular markers for diabetes mellitus (DM) diagnosis and treatment.

METHODS

The expression level of miR-296-5p was determined in tissue samples of 12 DM patients. The effect of miR-296-5p on proliferation of β-cells was examined using Cell Counting Kit-8 (CCK-8) and colony formation assay. The effect of miR-296-5p on cell cycle progression was analysed using flow cytometry. The target gene was verified using luciferase reporter assay. A rat diabetes model was used to assess the effect of miR-296-5p in vivo.

RESULTS

Overexpression of miR-296-5p suppressed cell proliferation, arrested cell cycle progression, and increased the healing rate of diabetic wounds both in vivo and in vitro. TargetScan analysis results showed that miR-296-5p is a direct regulator of SGLT2.

CONCLUSIONS

miR-296-5p can increase the healing rate of diabetic wounds and may be an effective molecular tool in DM diagnosis and therapy.

Extremely Low Organ Toxicity and Strong Antitumor Activity of miR-34-Regulated Oncolytic Coxsackievirus B3

Oncolytic virotherapies have emerged as new modalities for cancer treatment. We previously reported that coxsackievirus B3 (CVB3) is a novel oncolytic virus (OV) with a strong ability to lyse human non-small cell lung cancer cells; however, its non-specific toxicity against normal cells remains to be resolved. To improve its safety profile, microRNA target sequences complementary to miR-34a/c, which is expressed preferentially in normal cells, were inserted into the 5′ UTR or 3′ UTR of the CVB3 genome. In the presence of miR-34a/c, the gene-modified CVB3 could not replicate in normal cells. We also found that the pathogenicity of CVB3 was reduced to a greater extent by targeting miR-34a than miR-34c; in addition, it was more effective to insert the target sequences into the 3′ UTR rather than the 5′ UTR of the viral genome. Ultimately, we developed a double-miR-34a targeting virus (53a-CVB) by inserting miR-34a targets in both the 5′ UTR and 3′ UTR of the virus. 53a-CVB was minimally toxic to cells in normal tissue, but maintained nearly its full oncolytic activity in mice xenografted with human lung cancer. 53a-CVB is the first miR-34-regulated OV and represents a promising platform for the development of safe and effective anti-cancer therapies.

MiR-183-5p is required for non-small cell lung cancer progression by repressing PTEN

Lung cancer is the leading cause in all cancer deaths. A low survival rate and high recurrence rate of lung cancer make the endeavor to identify new, more effective therapies a primary goal. MicroRNAs (miRNAs) are regarded as regulators of tumorigenesis and it is known that miR-183-5p is significantly upregulated in non-small cell lung cancer (NSCLC), suggesting it has an oncogenic function in lung cancer. In this study, we found that miR-183-5p could promote lung carcinogenesis by directly targeting phosphatase tensin (PTEN). Further experiments indicated that miR-183-5p could suppress p53 and activate AKT signaling through phosphorylation. Moreover, our data indicated that miR-183-5p promoted tumor metastasis and tumor growth in vivo. Collectively, these results showed that miR-183-5p is required for NSCLC development through the suppressing PTEN, and might be a promising target in the diagnosis and treatment of lung cancer in the future.

Silencing of long noncoding RNA LINC00958 prevents tumor initiation of pancreatic cancer by acting as a sponge of microRNA-330-5p to down-regulate PAX8

Pancreatic cancer (PC) represents a relatively rare but severe malignancy worldwide. Accumulated studies have emphasized the potential of long noncoding RNA (lncRNA) as therapeutic strategies for several human cancers. Thus, we aimed to investigate whether a novel non-coding RNA regulatory circuitry involved in PC. Aberrantly expressed lncRNAs and mRNAs were screened out of microarray database. Following the determination of RNA expression, PANC-1 and BxPC-3 PC cells were adopted, after which the expression of miR-330-5p, PAX8 and LINC00958 were subsequently altered. RNA crosstalk was validated by dual-luciferase reporter gene assay. In order to detect whether LINC00958 could act as ceRNA to competitively sponge miR-330-5p and regulate PAX8, subcellular location of LINC00958 and interaction between LINC00958 and miR-330-5p were measured by FISH and RNA pull down respectively. The epithelial mesenchymal transition (EMT) process, cell invasion, and tumor growth were determined in vitro and in vivo. LINC00958 and PAX8 were up-regulated, while miR-330-5p was down-regulated during PC. LINC00958 mainly expressed in the cytoplasm and LINC00958 competitively sponged miR-330-5p. Upregulated miR-330-5p or downregulated PAX8 inhibited the EMT process as well as the invasion and metastasis ability of the PC cells. Moreover, the results indicated that miR-330-5p negatively targeted PAX8, and LINC00958 ultimately showcasing its ability to bind to miR-330-5p through its interaction with AGO2. Therefore, silencing of LINC00958 may bind to miR-330-5p to inhibit PAX8 in a competitive fashion, thereby preventing the progression of PC.

MicroRNA-34a suppresses breast cancer cell proliferation and invasion by targeting Notch1

MicroRNAs (miRs) have been reported to serve critical roles in the progression of tumors. However, thus far, the role of miR-34a in breast cancer is largely unknown. Therefore, the present study aimed to investigate the expression and role of miR-34a in breast cancer, and to further explore the underlying molecular mechanism. Reverse transcription-quantitative polymerase chain reaction was performed to detect the level of miR-34a in human breast cancer tissues. In addition, the role of miR-34a in MCF-7 breast cancer cells was investigated by performing miR-34a overexpression or downregulation through transfection with miR-34a mimic or inhibitor, respectively. Next, the viability and invasion of the MCF-7 cells were respectively analyzed by MTT assay and transwell assay, while apoptosis and cell cycle progression were examined by flow cytometry. Furthermore, associated protein levels were measured using western blotting. The results demonstrated that miR-34a was downregulated in human breast cancer tissues in comparison with the adjacent normal tissues. In addition, Notch1 was demonstrated to be a direct target of miR-34a. miR-34a mimic transfection inhibited MCF-7 cell viability, induced cell apoptosis and G1 phase arrest, and prevented cell invasion, while miR-34a inhibitor transfection resulted in the opposite effects. In conclusion, the presented data indicated that miR-34a suppressed breast cancer cell proliferation and invasion, and its effect may partly be exerted by targeting Notch1.

Knockdown of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 inhibits the proliferation and migration of bladder cancer cells by modulating the microRNA-34a/cyclin D1 axis

Long non‑coding RNA (lncRNA) metastasis associated lung adenocarcinoma transcript 1 (MALAT1) has been demonstrated to participate in the development and progression of some common cancer types, including bladder cancer (BC). However, the regulatory mechanism of MALAT1 underlying BC growth and metastasis remains to be fully elucidated. The present study revealed that MALAT1 was significantly upregulated in BC tissues and cell lines compared with the adjacent non‑tumour tissues and the normal urinary tract epithelial cell line SV‑HUC‑1, respectively. The expression levels of MALAT1 were higher in stage III‑IV BC tissues when compared with that in stage I‑II tissues. Furthermore, knockdown of MALAT1 significantly inhibited BC cell proliferation and migration by targeting microRNA (miR)‑34a. The expression levels of miR‑34a were significantly decreased in BC tissues and cell lines compared with that of adjacent non‑tumour tissues and SV‑HUC‑1 cells. In addition, the expression of miR‑34a was inversely correlated with the expression of MALAT1 in BC tissues. The present study revealed that cyclin D1 (CCND1) was identified as a target gene of miR‑34a, and its expression was negatively mediated by miR‑34a in BC cells. Notably, the upregulation of CCND1 impaired the effect of MALAT1 inhibition on BC cell proliferation and migration. In addition, the expression levels of CCND1 were significantly increased in BC tissues and cell lines. In conclusion, the present findings demonstrated that the knockdown of lncRNA MALAT1 inhibits the proliferation and migration of BC cells by modulating the miR‑34a/CCND1 axis, suggesting that the MALAT1/miR‑34a/CCND1 axis may be a potential therapeutic target for BC treatment.

RETRACTED: MicroRNA-494 inhibition alleviates acute lung injury through Nrf2 signaling pathway via NQO1 in sepsis-associated acute respiratory distress syndrome

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Concern was raised about the reliability of the Western blot results in Figures 5G,H+I, which appear to have a similar phenotype as many other publications, as detailed here: https://pubpeer.com/publications/7C9483B2551952AD53CCFCE206C4EB; and here: https://docs.google.com/spreadsheets/d/1r0MyIYpagBc58BRF9c3luWNlCX8VUvUuPyYYXzxWvgY/edit#gid=262337249. The journal requested that the corresponding author comment on these concerns and provide the raw data. The authors did not respond to this request and therefore the Editor-in-Chief decided to retract the article.

Overexpression of microRNA-34a Attenuates Proliferation and Induces Apoptosis in Pituitary Adenoma Cells via SOX7

Pituitary adenomas constitute one of the most common intracranial tumors and are typically benign. However, the role of the tumor suppressor microRNA-34a (miR-34a), which is implicated in other cancers, in pituitary adenoma pathogenesis remains largely unknown. miR-34a expression was compared between GH4C1 cancer cells and normal cells derived from the pituitary gland of Rattus norvegicus, and the effects of miR-34a on GH4C1 cell proliferation and apoptosis were examined. miR-34a target genes were identified and analyzed computationally. The mRNA levels of the miR-34a target genes were measured using qRT-PCR, and the protein levels of the differentially expressed targets were assessed by western blotting. miR-34a expression was significantly lower in GH4C1 cells, whereas miR-34a overexpression significantly inhibited GH4C1 cell proliferation and promoted cell apoptosis though SRY-box 7 (SOX7). Our data facilitate the development of a better understanding of the pathogenesis and treatment of pituitary adenomas by elucidating the crucial role of miR-34a in the development of pituitary adenomas.

Epidermal growth factor receptor (EGFR): A rising star in the era of precision medicine of lung cancer

Lung cancer is a leading cause of cancer mortality worldwide. In tumors, the important role of noncoding RNA regulatory networks has been more and more reveal. EGFR has been identified as an oncogenic driver of NSCLC, especially activating mutations EGFR and its inhibition with specific TKIs can generate dramatic tumor responses. Studies have shown that EGFR plays significant roles in the progression of NSCLC. Subset analysis of the small proportion of patients with EGFR-mutant lung cancer showed a disease-free survival benefit, but was underpowered to detect a survival advantage. Herein, we highlight the progression of EGFR, noncoding RNA, and their roles in carcinogenesis. We also focus on anti-lung cancer drug development and EGFR-related drug resistance.

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.

A Semi-Supervised Learning Algorithm for Predicting Four Types MiRNA-Disease Associations by Mutual Information in a Heterogeneous Network

Increasing evidence suggests that dysregulation of microRNAs (miRNAs) may lead to a variety of diseases. Therefore, identifying disease-related miRNAs is a crucial problem. Currently, many computational approaches have been proposed to predict binary miRNA-disease associations. In this study, in order to predict underlying miRNA-disease association types, a semi-supervised model called the network-based label propagation algorithm is proposed to infer multiple types of miRNA-disease associations (NLPMMDA) by mutual information derived from the heterogeneous network. The NLPMMDA method integrates disease semantic similarity, miRNA functional similarity, and Gaussian interaction profile kernel similarity information of miRNAs and diseases to construct a heterogeneous network. NLPMMDA is a semi-supervised model which does not require verified negative samples. Leave-one-out cross validation (LOOCV) was implemented for four known types of miRNA-disease associations and demonstrated the reliable performance of our method. Moreover, case studies of lung cancer and breast cancer confirmed effective performance of NLPMMDA to predict novel miRNA-disease associations and their association types.

MiR-146a-5p inhibits cell proliferation and cell cycle progression in NSCLC cell lines by targeting CCND1 and CCND2

Previous studies have indicated that miR-146a-5p acts as an oncogene in several types of cancer, yet a tumor suppressor gene in others. In non-small cell lung cancer (NSCLC), one report showed that it was downregulated and played the role of tumor suppressor. However, another study showed that miR-146a-5p was overexpressed in the serum of NSCLC patients compared to healthy controls. Therefore, it is obvious that further study of the function of miR-146a-5p in NSCLC is necessary to fully understand its importance. Herein, we have verified that miR- 146a- 5p acts as a tumor suppressor in NSCLC. Our data revealed that the expression level of miR-146a-5p was significantly decreased in several human NSCLC cell lines, and also less abundant in human NSCLC tissues, when compared with controls. Moreover, we observed that miR-146a-5p could suppress cell proliferation, both in vitro and in vivo. Our results also showed that miR-146a-5p directly targeted the 3′-UTR of CCND1 and CCND2 mRNAs as well as decreased their expression at both mRNA and protein levels, causing cell cycle arrest at the G0/G1 phase. Furthermore, siRNA-mediated downregulation of CCND1 or CCND2 yielded the same effects on proliferation and cell cycle arrest as miR-146a-5p upregulation did in the NSCLC cell lines. We confirmed that the expression of miR-146a-5p had negative relationship with CCND1 or CCND2. Besides, we also found that miR-146a-5p could inhibit tumor growth in xengroft mouse models, and CCND1 and CCND2 were downregulated in miR-146a-5p overexpressed xengroft tumor tissues. In summary, our results demonstrated that miR-146a-5p could suppress the proliferation and cell cycle progression in NSCLC cells by inhibiting the expression of CCND1 and CCND2.

Onco-miR-130 promotes cell proliferation and migration by targeting TGFβR2 in gastric cancer

MicroRNAs (miRNAs) have been proved to play crucial roles in tumorigenesis. TGFβ signal pathway abnormality is found in various cancers and correlates with tumor proliferation and metastasis. However, the mechanisms underlying the dys-regulation of TGFβR2 expression in GC have not been investigated yet. In this study, we found that the TGFβR2 protein was clearly repressed in tumor tissues, while miR-130 expression level was dramatically increased in GC tissues. Firefly luciferase activity assay revealed that miR-130 could directly bind to 3′UTR of TGFβR2 mRNA. Meanwhile, miR-130 mimics lead to the decreased TGFβR2 protein levels, while miR-130 inhibitors enhanced TGFβR2 expression in SGC7901 cells. Subsequent functional experiments showed that overexpressed miR-130 could promote proliferation and migration of SGC7901 cells. And siRNA-mediated TGFβR2 down-regulation could simulate the effects of miR-130 mimics on phenotypes of SGC7901 cells. Furthermore, there existed intense relationship between the expression level of miR-130 and epithelial-mesenchymal markers. Our results demonstrated that miR-130 was an oncogene by directly targeting TGFβR2 in GC.

mTOR signaling-related MicroRNAs and Cancer involvement

MicroRNAs (miRNAs) are a class of single-stranded RNAs, 18-23 nucleotides in length that regulate gene expression at the post-transcriptional level. Dysregulation of miRNAs has been closely associated with the development of cancer. In the process of tumorigenesis, mammalian target of rapamycin (mTOR) plays important roles, and the mTOR signaling pathway is aberrant in various types of human cancers, including non-small cell lung cancer (NSCLC), breast cancer, prostate cancer, as well as others. However, the relationship between miRNAs and the mTOR signaling pathway is indistinct. Herein, we not only summarize the progress of miRNAs and the mTOR signaling pathway in cancers, but also highlight their role in the diagnosis and treatment in the clinic.

Biology of MiR-17-92 Cluster and Its Progress in Lung Cancer

MicroRNAs, a class of short endogenous RNAs, acting as post-transcriptional regulators of gene expression, mostly silence gene expression via binding imperfectly matched sequences in the 3'UTR of target mRNA. MiR-17-92, a highly conserved gene cluster, has 6 members including miR-17, miR-18a, miR-19a, miR-20a, miR-19b-1 and miR-92a. The miR-17-92 cluster, regarded as oncogene, is overexpressed in human cancers. Lung cancer is the leading cause of death all over the world. The molecular mechanism of lung cancer has been partly known at the levels of genes and proteins in last decade. However, new prognosis biomarkers and more target drugs should be developed in future. Therefore, noncoding RNAs, especially miRNAs, make them as new potentially clinical biomarkers for diagnosis and prognosis. In this review, we focus the current progress of miR-17-92 cluster in lung cancer.

Direct repression of the oncogene CDK4 by the tumor suppressor miR-486-5p in non-small cell lung cancer

MicroRNAs are a class of non-coding single-stranded RNA, 20-23 nucleotide in length, which can be involved in the regulation of gene expression. Through binding with 3′-untranslated regions (3′-UTR), microRNAs can cause degradation of target mRNAs or inhibition of translation, and thus regulating the expression of genes at the post-transcriptional level. In this study, we found that miR-486-5p was significantly downregulated in non-small cell lung cancer (NSCLC) tissues and cell lines, suggesting that miR-486-5p might function as a tumor suppressor in lung cancer. Additionally, we showed that CDK4, an oncogene that plays an important role in cell cycle G1/S phase progression, was directly targeted by miR-486-5p. Furthermore, our data reveals that knockdown of CDK4 by siRNA can inhibit cell proliferation, promote apoptosis, and impede cell-cycle progression. In epigenetics, the upstream promoter of miR-486-5p was strongly regulated by methylation in NSCLC. Collectively, our results suggest that miR-486-5p could not only inhibit NSCLC by downregulating the expression of CDK4, but also be as a promising and potent therapy in the near future.

Predictive relevance of miR-34a, miR-224 and miR-342 in patients with advanced squamous cell carcinoma of the lung undergoing palliative chemotherapy

Attributing to their pathophysiological role and stability in biological samples, microRNAs (miRNAs) have the potential to become valuable predictive markers for non-small cell lung cancer (NSCLC). Samples of biopsy tissue constitute suitable material for miRNA profiling with the aim of predicting the effect of palliative chemotherapy. The present study group included 81 patients (74 males, 7 females, all smokers or former smokers) with the squamous cell carcinoma (SCC) histological subtype of NSCLC at a late stage (3B or 4). All patients received palliative chemotherapy based on platinum derivatives in combination with paclitaxel or gemcitabine. The expression of 17 selected miRNAs was measured by reverse transcription-quantitative polymerase chain reaction in tumor tissue macrodissected from formalin-fixed paraffin-embedded (FFPE) tissue samples. To predict the effect of palliative chemotherapy, the association between gene expression levels and overall survival (OS) time was analyzed. From the 17 miRNAs of interest, low expression levels of miR-342 and high expression levels of miR-34a and miR-224 were associated with a reduced OS time in subgroups of patients based on smoking status and treatment modality. Using cluster analysis, associations between combinations of miR-34a, -224 and -342 expression levels with patient survival were identified. The present study revealed that patients with the simultaneous high expression of miR-224 and -342 had a similar prognostic outcome to those with the low expression of miR-224 and -342, which was significantly reduced, compared with patients exhibiting high expression of either miR-224 or miR-342 with low expression of the other. We hypothesize that the effect of a particular miRNA is dependent on the expression level of other members of the miRNA network. This finding appears to complicate survival analyses based on individual miRNAs as markers. In conclusion, the present study provides evidence that specific miRNAs were associated with OS time, which may be candidate predictors for the effectiveness of palliative treatment in SCC lung cancer patients. This objective can be better achieved by combining more markers together than by using individual miRNAs.

tRF-Leu-CAG promotes cell proliferation and cell cycle in non-small cell lung cancer

tRNA-derived RNA fragments (tRFs), non-coding single-stranded RNAs with 14-35 nt in length, were found to play important roles in gene regulation, even in carcinogenesis. In this study, we investigated the expression of tRF-Leu-CAG in human non-small cell lung cancer (NSCLC) and its function in the cell proliferation and cell cycle of NSCLC. The expression level of tRF-Leu-CAG was detected in NSCLC tissues, cell lines, and sera. tRF-Leu-CAG RNA levels were higher in NSCLC tumor tissues than in normal tissues, and also upregulated in NSCLC cell lines. A significant relationship was observed between stage progression and tRF-Leu-CAG in NSCLC sera. We found that in H1299 cells, inhibition of tRF-Leu-CAG suppressed cell proliferation and impeded cell cycle. AURKA was also repressed with the knockdown of tRF-Leu-CAG. Thus, our study revealed that tRF-Leu-CAG may be involved in regulating AURKA and could be a new diagnostic marker and potential therapeutic target in NSCLC.