MicroRNA‑21 regulates the expression of BTG2 in HepG2 liver cancer cells

A comprehensive review of miR-21 in liver disease: Big impact of little things

microRNAs (miRNAs), a class of non-coding RNA with 20-24 nucleotides, are defined as the powerful regulators for gene expression. miR-21 is a multifunctional miRNA enriched in the circulatory system and multiple organs, which not only serves as a non-invasive biomarker in disease diagnosis, but also participates in many cellular activities. In various chronic liver diseases, the increase of miR-21 affects glycolipid metabolism, viral infection, inflammatory and immune cell activation, hepatic stellate cells activation and tissue fibrosis, and autophagy. Moreover, miR-21 is also a liaison in the deterioration of chronic liver disease to hepatocellular carcinoma (HCC), and it impacts on cell proliferation, apoptosis, migration, invasion, angiogenesis, immune escape, and epithelial-mesenchymal transformation by regulating target genes expression in different signaling pathways. In current research on miRNA therapy, some natural products can exert the hepatoprotective effects depending on the inhibition of miR-21 expression. In addition, miR-21-based therapeutic also play a role in regulating intracellular miR-21 levels and enhancing the efficacy of chemotherapy drugs. Herein, we systemically summarized the recent progress of miR-21 on biosynthesis, biomarker function, molecular mechanism and miRNA therapy in chronic liver disease and HCC, and looked forward to outputting some information to enable it from bench to bedside.

Circulating miRNA's biomarkers for early detection of hepatocellular carcinoma in Egyptian patients based on machine learning algorithms

Liver cancer, which ranks sixth globally and third in cancer-related deaths, is caused by chronic liver disorders and a variety of risk factors. Despite therapeutic improvements, the prognosis for Hepatocellular Carcinoma (HCC) remains poor, with a 5-year survival rate for advanced cases of less than 12%. Although there is a noticeable decrease in the frequency of cases, liver cancer remains a significant worldwide health concern, with estimates surpassing one million cases by 2025. The prevalence of HCC has increased in Egypt, and it includes several neoplasms with distinctive messenger RNA (mRNA) and microRNA (miRNA) expression profiles. In HCC patients, certain miRNAs, such as miRNA-483-5P and miRNA-21, are upregulated, whereas miRNA-155 is elevated in HCV-infected people, encouraging hepatocyte proliferation. Short noncoding RNAs called miRNAs in circulation have the potential as HCC diagnostic and prognostic markers. This paper proposed a model for examining circulating miRNAs as diagnostic and predictive markers for HCC in Egyptian patients and their clinical and pathological characteristics. The proposed HCC detection model consists of three main phases: data preprocessing phase, feature selection based on the proposed Binary African Vulture Optimization Algorithm (BAVO) phase, and finally, classification as well as cross-validation phase. The first phase namely the data preprocessing phase tackle the main problems associated with the adopted datasets. In the feature selection based on the proposed BAVO algorithm phase, a new binary version of the BAVO swarm-based algorithm is introduced to select the relevant markers for HCC. Finally, in the last phase, namely the classification and cross-validation phase, the support vector machine and k-folds cross-validation method are utilized. The proposed model is evaluated on three studies on Egyptians who had HCC. A comparison between the proposed model and traditional statistical studies is reported to demonstrate the superiority of using the machine learning model for evaluating circulating miRNAs as diagnostic markers of HCC. The specificity and sensitivity for differentiation of HCC cases in comparison with the statistical-based method for the first study were 98% against 88% and 99% versus 92%, respectively. The second study revealed the sensitivity and specificity were 97.78% against 90% and 98.89% versus 92.5%, respectively. The third study reported 83.2% against 88.8% and 95.80% versus 92.4%, respectively. Additionally, the results show that circulating miRNA-483-5p, 21, and 155 may be potential new prognostic and early diagnostic biomarkers for HCC.

Pancreatic cancer and exosomes: role in progression, diagnosis, monitoring, and treatment

Pancreatic cancer (PC) is one of the most dangerous diseases that threaten human life, and investigating the details affecting its progression or regression is particularly important. Exosomes are one of the derivatives produced from different cells, including tumor cells and other cells such as Tregs, M2 macrophages, and MDSCs, and can help tumor growth. These exosomes perform their actions by affecting the cells in the tumor microenvironment, such as pancreatic stellate cells (PSCs) that produce extracellular matrix (ECM) components and immune cells that are responsible for killing tumor cells. It has also been shown that pancreatic cancer cell (PCC)-derived exosomes at different stages carry molecules. Checking the presence of these molecules in the blood and other body fluids can help us in the early stage diagnosis and monitoring of PC. However, immune system cell-derived exosomes (IEXs) and mesenchymal stem cell (MSC)-derived exosomes can contribute to PC treatment. Immune cells produce exosomes as part of the mechanisms involved in the immune surveillance and tumor cell-killing phenomenon. Exosomes can be modified in such a way that their antitumor properties are enhanced. One of these methods is drug loading in exosomes, which can significantly increase the effectiveness of chemotherapy drugs. In general, exosomes form a complex intercellular communication network that plays a role in developing, progressing, diagnosing, monitoring, and treating pancreatic cancer.

MiRNA-21-5p Accelerates EMT and Inhibits Apoptosis of Laryngeal Carcinoma via Inhibiting KLF6 Expression

The incidence of laryngeal carcinoma accounts for 1 to 5% of systemic malignancies and ranks second among head and neck malignancies. Screening more effective targets are meaningful for the treatment of laryngeal carcinoma. The purpose was to research the action of miR-21-5p in the occurrence of laryngeal carcinoma. Genecards combined with g:profiler was used for cluster analysis to predict gene-related miRNAs. Q-PCR assay was performed for measuring the level of miR-21-5p and Kruppel-like factor 6 (KLF6). miR-21-5p-mimic, miR-21-5p-inhibitor and sh-KLF6 were transfected using LipofectamineTM 2000. Both CCK-8 and EdU experiments were undertaken to detect cell proliferation ability. Western blot was used to detect apoptosis and epithelial-mesenchymal transition (EMT) related proteins. Wound healing assay and transwell assay were undertaken for migration and invasion, respectively. Three online software (ENCORI, miRWalk, and miRDB) were applied to screen the downstream of miR-21-5p. At the same time, a dual-luciferase reporter experiment was processed to verify the binding. Finally, a rescue experiment was applied to reveal the mediating role of miR-21-5p and KLF6. MiR-21-5p expressed highly in laryngeal carcinoma tissues and cell lines. Knockdown of miR-21-5p reduced the EMT, while enhancing apoptosis of laryngeal carcinoma cell lines. MiR-21-5p targeted KLF6 with negative relationships. The rescue assay results confirmed that sh-KLF6 rescued the action of miR-21-5p knockdown in developing laryngeal carcinoma cells. MiR-21-5p promotes the occurrence and development of laryngeal cancer by targeting KLF6. This finding may provide new insights into miRNA as a biomarker for diagnosing and treating laryngeal carcinoma in the future.

MiR-21-5p protects against ischemic stroke by targeting IL-6R

Background

Ischemic stroke is a brain dysfunction disease caused by vascular obstruction. The expression of many kinds of microRNAs (miRNAs) is related to ischemic stroke. MiRNA has the ability to reduce or save ischemic injury. Therefore, we aimed to explore the protective miRNA in the ischemia-reperfusion process.

Methods

The Gene Expression Omnibus (GEO) peripheral RNA sequencing (RNA-seq) datasets of ischemic stroke patients were analyzed to search for differentially expressed miRNAs in the ischemia-reperfusion process. The expression level of miRNA in 60 patients with ischemic stroke and 23 age-matched healthy control inpatients was tested by quantitative reverse transcription polymerase chain reaction (qRT-PCR). The significantly changed miRNAs were verified through comparison of the peripheral blood of healthy people and patients of the hospital. The in-vitro ischemia-reperfusion model was established through oxygen-glucose deprivation (OGD) treated HEMC-1 cells. The cell viabilities and cell apoptosis are detected by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide (MTT) assay and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay, respectively. Apoptosis-related proteins including Bcl-2, Bax, caspase-3, and caspase-9 expression levels were verified by western blot. Predict the combination of hsa-miR-21-5p and interleukin-6 receptor (IL-6R) through TargetScan database, clone the 2964-2961 site of IL-6R-3'-untranslated region (3'-UTR), establish IL-6R-3'-UTR and IL-6R-3'-UTR mutant plasmids, copy and clone wild type and mutant IL-6R-3'-UTR into luciferase report vector pGL3 respectively, and detect the activity of luciferase. The expression of hsa-miR-21-5p was regulated by using hsa-miR-21-5p mimic and hsa-miR-21-5p inhibitor.

Results

Through RNA-seq analysis, it was revealed that "hsa-miR-548ar-3p", "hsa-miR-651-5p", "hsa-miR-142-3p", "hsa-miR-21-5p", and "hsa-miR-30e-5p" were notably lower in ischemia patients, and that "hsa-miR-21-5p" was significantly decreased in the peripheral blood of hospital patients. Luciferase assay showed that hsa-miR-21-5p could directly bind to the 3'-UTR of the IL-6R gene and inhibit IL-6R translation; the level of IL-6R was also elevated in patients. In the OGD-treated HMEC-1 cells, overexpressed hsa-miR-21-5p mimic could enhance cell viabilities and decrease cell apoptosis. Moreover, IL-6R overexpression could reduce the protective effects of hsa-miR-21-5p.

Conclusions

In the peripheral blood of ischemia patients, hsa-miR-21-5p is significantly decreased and IL-6R is elevated. The "hsa-miR-21-5p" could bind to the IL-6R gene and suppress IL-6R expression, thus alleviating the damage of OGD treatment in HMEC-1 cells.

JPHYD Inhibits miR-21-5p/Smad7-Mediated Epithelial-Mesenchymal Transition of Hepatocellular Carcinoma Cells

Background. Studies have shown that Jianpi Huayu Decoction (JPHYD) can inhibit the growth of hepatocellular carcinoma cells, but the mechanism of its effect was not clear at present. Methods. We assessed the effect of JPHYD using liver cancer cells as in vitro cell model and xenograft tumor as in vivo model. CCK8, EdU, wound-healing, and transwell assays were performed to assess the cell growth, migration, and invasion of hepatocellular carcinoma (HCC) cell lines HepG2 and MHCC97H. Western blot assay was performed to observe the protein level of E-cadherin, Smad7, N-cadherin, Snail, Smad3, Vimentin, and Zeb1. qRT-PCR assay was used to observe the expression of miR-21-5p in clinical liver cancer tissue samples and in HepG2 and MHCC97H cells. Animal tumorigenesis experiments and in vivo imaging experiments were performed to assess the results of in vitro experiments. Results. We found that JPHYD could inhibit the proliferation, invasion, and migration of hepatocellular carcinoma cells and JPHYD decreased the level of N-cadherin, Snail, Vimentin, Smad3, and Zeb1 and increased E-cadherin and Smad7 proteins. The expression of miR-21-5p was increased while that protein of Smad7 was decreased in HCC tissues. The vivo experiments also showed that miR-21-5p could promote the migration of HCC cells. JPHYD decreased miR-21-5p expression. The same results have been found in animal studies. Conclusion. Our results indicated that JPHYD inhibited epithelial-mesenchymal transition by increasing Smad7 expression and inhibiting miR-21-5p. Therefore, blocking the occurrence and development of EMT may be a new mechanism of JPHYD’s anti-liver cancer effect.

UTMD-mediated delivery of miR-21-5p inhibitor suppresses the development of lung cancer

BACKGROUND

Ultrasound-targeted microbubble destruction (UTMD) is a new type of gene delivery technology. MiR-21-5p was highly expressed in a variety of cancers. In this paper, miR-21-5p inhibitor was transfected into lung cancer cells by UTMD to observe its role in lung cancer.

METHODS

StarBase was used to analyze the miR-21-5p expression in lung cancer patients and its relationship with the prognosis of the patients. MiR-21-5p expression in lung cancer tissues or cell lines was determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Effects of gradient concentration (0, 5, 10, 20, 30%) of SonoVue or gradient mechanical index (MI) (0, 0.5, 1, 1.5, 2 W/cm²) on the cell viability were detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). The targeting relationship between miR-21-5p and B-cell translocation gene 2 (BTG2) was predicted by TargetScan and confirmed by dual-luciferase reporter assay, while the expressions of the two genes were determined by qRT-PCR. Through liposome transfection or UTMD transfection, the effects of miR-21-5p/BTG2 on the biological behaviors of lung cancer cells, the size of xenograft tumors and the expressions of ki67 and miR-21-5p were measured by qRT-PCR, western blot, cell function experiments and immunohistochemistry, respectively.

RESULTS

MiR-21-5p expression was upregulated in lung cancer, which was associated with a poor prognosis. The optimal ultrasound conditions were 10% SonoVue concentration and 1 W/cm². UTMD transfection exerted a stronger effect than liposome transfection. MiR-21-5p promoted cell viability, proliferation and migration yet suppressed apoptosis by targeting BTG2. MiR-21-5p inhibitor reduced the size and volume of xenograft tumor and the expressions of ki67 and miR-21-5p in xenograft tumor tissues.

CONCLUSION

UTMD-mediated miR-21-5p inhibitor can more effectively suppress the development of lung cancer.

Ribonucleic acid-binding protein CPSF6 promotes glycolysis and suppresses apoptosis in hepatocellular carcinoma cells by inhibiting the BTG2 expression

Hepatocellular carcinoma (HCC) is currently the sixth most common malignancy and the second major cause of tumor-related deaths in the world. This study aimed to investigate the role of cleavage and polyadenylation factor-6 (CPSF6) and B-cell translocation gene 2 (BTG2) in regulating the glycolysis and apoptosis in HCC cells. The RNA and protein expression of CPSF6 and BTG2 in normal hepatocyte and HCC were, respectively, detected by reverse transcription quantitative real-time polymerase chain reaction (RT-qPCR) analysis and Western blot analysis. The viability and apoptosis of transfected Huh-7 cells were, respectively, analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and terminal deoxynucleotidyl transferase (TdT) dUTP Nick-End Labeling (TUNEL) assay. The expression of apoptosis-related proteins and HK-2 in transfected Huh-7 cells was also detected by Western blot analysis. The levels of glucose and lactate in the culture supernatant of transfected Huh-7 cells were, respectively, detected with the glucose assay kit and lactate assay kit. The interaction of CPSF6 and BTG2 was confirmed by RNA binding protein immunoprecipitation (RIP) assay. As a result, CPSF6 expression was increased while BTG2 expression was decreased in Huh-7 cells. Interference with CPSF6 suppressed the viability and glycolysis, and promoted the apoptosis of Huh-7 cells. Furthermore, CPSF6 interacted with BTG2 and interference with CPSF6 upregulated the BTG2 expression and inhibited the protein kinase B (AKT)/extracellular signal-regulated kinase (ERK)/nuclear factor (NF)-κB pathway. Interference with BTG2 could partially reverse the above cell changes caused by interference with CPSF6. In conclusion, CPSF6 inhibited the BTG2 expression to promote glycolysis and suppress apoptosis in HCC cells by activating AKT/ERK/NF-κB pathway.

Platelet microparticles-derived miR-25-3p promotes the hepatocyte proliferation and cell autophagy via reducing B-cell translocation gene 2

Platelets are critical regulators of liver regeneration, but the mechanisms are still not fully understood. Platelets have been shown to contain a wide variety of microRNAs (miRNAs) and play an important role in many diseases. However, the mechanism that how the platelet microparticles (PMPs)-derived miRNA regulate the hepatocyte proliferation is not very clear. In this study, we have successfully isolated and identified PMPs. We also found that PMPs, which could be well integrated into the HHL-5 cells, could upregulate the level of miR-25-3p in HHL-5 cells. Meanwhile, we found that PMPs-derived miR-25-3p promoted HHL-5 cells proliferation by accelerating cells into the S phase, and enhanced the autophagy by increasing the LC3II expression and reducing the P62 expression. Then, we proved that the miR-25-3p could target the B-cell translocation gene 2 (BTG2) and downregulate the expression levels of the BTG2 gene in HHL-5 cells. In addition, the overexpression of BTG2 significantly inhibited the proliferation and autophagy abilities of HHL-5 cells, while cotransfected miR-25-3p mimics or PMPs could partially rescue HHL-5 cells proliferation and autophagy. Furthermore, we proved that PMPs accelerated hepatocyte proliferation by regulating autophagy pathways. Therefore, PMPs-derived miR-25-3p promoted HHL-5 cell proliferation and autophagy by targeting BTG2, which may be a new therapeutic method for liver regeneration.

MicroRNAs: potential biomarkers for diagnosis and prognosis of different cancers

A thorough understanding of the tumor environment and underlying genetic factors helps in the better formulation of cancer management strategies. Availability of efficient diagnostic and prognostic biomarkers facilitates early detection and progression of the disease. MicroRNAs affect different biological processes participating in tumorigenesis through regulation of their target genes. An expanding list of unique RNAs and understanding of their regulatory role has opened up a new field in cancer research. Based on a comprehensive literature search, we identified 728 miRNAs dysregulated in sixteen cancer types namely bladder cancer (BC), breast cancer (BrC), cervical cancer (CC), colorectal cancer (CRC), esophageal cancer (EC), endometrial cancer (EnC), gastric cancer (GC), hepatocellular cancer (HCC), head and neck squamous cell cancer (HNSCC), lung cancer (LC), ovarian cancer (OC), pancreatic cancer (PC), prostate cancer (PrC), renal cell cancer (RCC), skin cancer (SC), and thyroid cancer (TC). Expression of 43 miRNAs was either upregulated or downregulated in six or more of these cancers. Finally, seven miRNAs namely mir-18a, mir-21, mir-143/145, mir-210, mir-218, mir-221, showing maximum dysregulation, either up- or down-regulation in the majority of cancers, were selected for a detailed presentation of their expression and evaluation of their potential as biomarkers in the diagnosis and prognosis of different cancers.

Engineering combinatorial and dynamic decoders using synthetic immediate-early genes

Many cell- and tissue-level functions are coordinated by intracellular signaling pathways that trigger the expression of context-specific target genes. Yet the input–output relationships that link pathways to the genes they activate are incompletely understood. Mapping the pathway-decoding logic of natural target genes could also provide a basis for engineering novel signal-decoding circuits. Here we report the construction of synthetic immediate-early genes (SynIEGs), target genes of Erk signaling that implement complex, user-defined regulation and can be monitored by using live-cell biosensors to track their transcription and translation. We demonstrate the power of this approach by confirming Erk duration-sensing by FOS, elucidating how the BTG2 gene is differentially regulated by external stimuli, and designing a synthetic immediate-early gene that selectively responds to the combination of growth factor and DNA damage stimuli. SynIEGs pave the way toward engineering molecular circuits that decode signaling dynamics and combinations across a broad range of cellular contexts.

Ravindran et al. report the construction of synthetic immediate-early genes (SynIEGs), target genes of the Erk signaling pathway. SynIEGs implement user-defined regulation while tracking transcription and translation. This study underscores post-transcriptional regulation in signal decoding that may be masked by analyses of RNA abundance alone.

Epithelial cell -derived microvesicles: A safe delivery platform of CRISPR/Cas9 conferring synergistic anti-tumor effect with sorafenib

Safe and efficient intracellular delivery of CRISPR/Cas9 is a key step for effective therapeutic genome editing in a wide range of diseases. This remains challenging due to multiple drawbacks of the currently available vehicles. Here we report that epithelial cell -derived microvesicles (MVs) function as safe and natural carriers for efficient delivery of CRISPR/Cas9 to treat cancer. In our study, compared to epithelial cell -derived MVs, cancer -derived MVs were quickly absorbed intracellularly by recipient cancer cells in vitro and showed selective accumulation in tumors of HepG2 xenografts in vivo, due to their cancer cell tropism dependent targeting. Surprisingly, synergistic anti-tumor effect of sgIQ 1.1 loaded Cas9MVs/HEK293 + sorafenib was better than sgIQ 1.1 + Cas9MVs/HepG2 + sorafenib in vitro. In addition, qPCR results showed that miR-21 and miR-181a expression were upregulated in HepG2 cells treated with cancer cell -derived MVs that might support the cancer progression. Further, treatment of HepG2 xenografts with sgIQ 1.1 loaded Cas9MVs/HEK293 showed enhanced anti-cancer effect than sgIQ 1.1 + Cas9MVs/HepG2. Therefore, we conclude that normal cells -derived MVs can act as better and safe natural delivery systems for cancer therapeutics in the future.

MicroRNA dysregulation interplay with childhood abdominal tumors

Abdominal tumors (AT) in children account for approximately 17% of all pediatric solid tumor cases, and frequently exhibit embryonal histological features that differentiate them from adult cancers. Current molecular approaches have greatly improved the understanding of the distinctive pathology of each tumor type and enabled the characterization of novel tumor biomarkers. As seen in abdominal adult tumors, microRNAs (miRNAs) have been increasingly implicated in either the initiation or progression of childhood cancer. Moreover, besides predicting patient prognosis, they represent valuable diagnostic tools that may also assist the surveillance of tumor behavior and treatment response, as well as the identification of the primary metastatic sites. Thus, the present study was undertaken to compile up-to-date information regarding the role of dysregulated miRNAs in the most common histological variants of AT, including neuroblastoma, nephroblastoma, hepatoblastoma, hepatocarcinoma, and adrenal tumors. Additionally, the clinical implications of dysregulated miRNAs as potential diagnostic tools or indicators of prognosis were evaluated.

Overexpression of long non-coding RNA cancer susceptibility 11 is involved in the development of chemoresistance to carboplatin in hepatocellular carcinoma

The long non-coding (lnc)RNA cancer susceptibility 11 (CASC11) promotes gastric cancer, however its role in other diseases is unknown. The present study demonstrated upregulation of lncRNA CASC11 and microRNA (miR)-21 in hepatocellular carcinoma (HCC). Furthermore, the expression of CASC11 was positively correlated with that of miR-21 in HCC tumors. Moreover, overexpression of lncRNA CASC11 led to upregulation of miR-21 in HCC cells, whereas overexpression of miR-21 had no effect on CASC11 levels. The levels of lncRNA CASC11 and miR-21 were found to be upregulated in the plasma of patients with HCC during chemotherapy. In vitro cell experiments demonstrated upregulation of lncRNA CASC11 in HCC cells treated with carboplatin. Additionally, overexpression of lncRNA CASC11 promoted, whereas its knockdown inhibited the viability of HCC cells following carboplatin treatment. Finally, overexpression of miR-21 ameliorated the effects of lncRNA CASC11 knockdown on cell viability. Thus, these findings suggest that upregulation of lncRNA CASC11 is involved in the development of chemoresistance to carboplatin in patients with HCC, via the upregulation of miR-21.

Solanine Attenuates Hepatocarcinoma Migration and Invasion Induced by Acetylcholine

AIM

Evidence has provided an explanation of the correlation between the nervous system and the tumor microenvironment. Neurotransmitters may be involved in different aspects of cancer progression. The glycoalkaloid solanine has been reported to suppress neural signaling pathways and exists in numerous plants, including Solanum nigrum, which have been demonstrated to inhibit cancer cell proliferation.

METHODS

We evaluated the potentials of solanine on inhibiting acetylcholine-induced cell proliferation and migration in hepatocellular carcinoma cells.

RESULTS

The results indicated that solanine markedly attenuated cell proliferation and migration via inhibiting epithelial-mesenchymal transition and matrix metalloproteinases in acetylcholine-treated Hep G2 cells. In addition, exosomes derived from acetylcholine-treated Hep G2 cells were isolated, and solanine showed inhibiting effects of extrahepatic metastasis on blocking cell proliferation in exosome-treated A549 lung carcinoma cells through regulating microRNA-21 expression.

CONCLUSION

Solanine has strong potential for application in integrative cancer therapy.

Pancreatic cancer cell-derived exosomal microRNA-27a promotes angiogenesis of human microvascular endothelial cells in pancreatic cancer via BTG2

Pancreatic cancer (PC) remains a primary cause of cancer-related deaths worldwide. Existing literature has highlighted the oncogenic role of microRNA-27a (miR-27a) in multiple cancers. Hence, the current study aimed to clarify the potential therapeutic role of PC cell-derived exosomal miR-27a in human microvascular endothelial cell (HMVEC) angiogenesis in PC. Initially, differentially expressed genes (DEGs) and miRs related to PC were identified by microarray analysis. Microarray analysis provided data predicting the interaction between miR-27a and BTG2 in PC, which was further verified by the elevation or depletion of miR-27a. Next, the expression of miR-27a and BTG2 in the PC tissues was quantified. HMVECs were exposed to exosomes derived from PC cell line PANC-1 to investigate the effects associated with PC cell-derived exosomes carrying miR-27a on HMVEC proliferation, invasion and angiogenesis. Finally, the effect of miR-27a on tumorigenesis and microvessel density (MVD) was analysed after xenograft tumour inoculation in nude mice. Our results revealed that miR-27a was highly expressed, while BTG2 was poorly expressed in both PC tissues and cell lines. miR-27a targeted BTG2. Moreover, miR-27a silencing inhibited PC cell proliferation and invasion, and promoted apoptosis through the elevation of BTG2. The in vitro assays revealed that PC cell-derived exosomes carrying miR-27a stimulated HMVEC proliferation, invasion and angiogenesis, while this effect was reversed in the HMVECs cultured with medium containing GW4869-treated PANC-1 cells. Furthermore, in vivo experiment revealed that miR-27a knockdown suppressed tumorigenesis and MVD. Taken together, cell-derived exosomes carrying miR-27a promotes HMVEC angiogenesis via BTG2 in PC.

MiR-21 in Substance P-induced exosomes promotes cell proliferation and migration in human colonic epithelial cells

Exosomes are cellular vesicles involved in intercellular communication via their specialized molecular cargo, such as miRNAs. Substance P (SP), a neuropeptide/hormone, and its high-affinity receptor, NK-1R, are highly expressed during colonic inflammation. Our previous studies show that SP/NK-1R signaling stimulates differential miRNA expression and promotes colonic epithelial cell proliferation. In this study, we examined whether SP/NK-1R signaling regulates exosome biogenesis and exosome-miRNA cargo sorting. Moreover, we examined the role of SP/NK-1R signaling in exosome-regulated cell proliferation and migration. Exosomes produced by human colonic NCM460 epithelial cells overexpressing NK-1R (NCM460-NK1R) were isolated from culture media. Exosome abundance and uptake were assessed by Western blot analysis (abundance) and Exo-Green fluorescence microscopy (abundance and uptake). Cargo-miRNA levels were assessed by RT-PCR. Cell proliferation and migration were assessed using xCELLigence technology. Colonic epithelial exosomes were isolated from mice pretreated with SP for 3 days. Cell proliferation in vivo was assessed by Ki-67 staining. SP/NK-1R signaling in human colonic epithelial cells (in vitro) and mouse colons (in vivo) increased 1) exosome production, 2) the level of fluorescence in NCM460s treated with Exo-Green-labeled exosomes, and 3) the level of miR-21 in exosome cargo. Moreover, our results showed that SP/NK-1R-induced cell proliferation and migration are at least in part dependent on intercellular communication via exosomal miR-21 in vitro and in vivo. Our results demonstrate that SP/NK-1R signaling regulates exosome biogenesis and induces its miR-21 cargo sorting. Moreover, exosomal miR-21 promotes proliferation and migration of target cells.NEW & NOTEWORTHY Substance P signaling regulates exosome production in human colonic epithelial cells and colonic crypts in wild-type mice. MiR-21 is selectively sorted into exosomes induced by Substance P stimulation and promotes cell proliferation and migration in human colonocytes and mouse colonic crypts.

The Impact of miRNA in Colorectal Cancer Progression and Its Liver Metastases

Colorectal cancer (CRC) is one of the most commonly diagnosed malignancies with a high incidence and mortality rate. An essential challenge in colorectal cancer management is to identify new prognostic factors that could better estimate the evolution and treatment responses of this disease. Considering their role in cancer development, progression and metastasis, miRNAs have become an important class of molecules suitable for cancer biomarkers discovery. We performed a systematic search of studies investigating the role of miRNAs in colorectal progression and liver metastasis published until October 2018. In this review, we present up-to-date information regarding the specific microRNAs involved in CRC development, considering their roles in alteration of Wnt/βcatenin, EGFR, TGFβ and TP53 signaling pathways. We also emphasize the role of miRNAs in controlling the epithelial⁻mesenchymal transition of CRC cells, a process responsible for liver metastasis in a circulating tumor cell-dependent manner. Furthermore, we discuss the role of miRNAs transported by CRC-derived exosomes in mediating liver metastases, by preparing the secondary pre-metastatic niche and in inducing liver carcinogenesis in a Dicer-dependent manner.

Lower expression of plasma-derived exosome miR-21 levels in HIV-1 elite controllers with decreasing CD4 T cell count

Exosome-derived miR-21 was independently associated with CD4 T cell decline in HIV-1-infected elite controllers (OR 0.369, 95% CI 0.137-0.994, p = 0.049). Also, a negative correlation between miR-21 expression and MCP-1 level was found (r = -0.649, p = 0.020), while no correlation between soluble biomarkers or cellular immune activation was found.

MiR-21 improves invasion and migration of drug-resistant lung adenocarcinoma cancer cell and transformation of EMT through targeting HBP1

This study was aimed at the investigation of the effects of miR-21 on drug resistance, invasion, migration, and epithelial-mesenchymal transition (EMT) of lung adenocarcinoma cells and the related molecular mechanisms. Cell viability of A549 cell line was measured by MTT assay. Wound healing assay and transwell assay were, respectively, employed to examine cell migration and invasion abilities. The cells were transfected with miR-21 mimic or inhibitor using Lipofectamine 3000. The target relationship between miR-21 and HBP1 was confirmed by luciferase reporter gene assay. Western blot and qRT-PCR were used to examine the expression of HBP1 and EMT-related molecules. Compared with A549 cells, drug resistance of A549/PTX cells and A549/DDP cells were obviously stronger. A549/PTX cells and A549/DDP cells had stronger ability of migration and invasion compared with parental A549 cells. Meanwhile, EMT of A549/PTX and A549/DDP was significantly higher than that of A549 cells. MiR-21 promoted migration, invasion, and EMT of human lung adenocarcinoma cancer cells. Our experiment also verified the target relationship between miR-21 and HBP1. MiR-21 may affect migration and invasion ability of drug-resistant lung adenocarcinoma cells by targeting HBP1, therefore modulating EMT.

Deciphering microRNA targets in pancreatic cancer using miRComb R package

MiRNAs are small non-coding RNAs that post-transcriptionally regulate gene expression. They play important roles in cancer but little is known about the specific functions that each miRNA exerts in each type of cancer. More knowledge about their specific targets is needed to better understand the complexity of molecular networks taking part in cancer. In this study we report the miRNA-mRNA interactome occurring in pancreatic cancer by using a bioinformatic approach called miRComb, which combines tissue expression data with miRNA-target prediction databases (TargetScan, miRSVR and miRDB). MiRNome and transcriptome of 12 human pancreatic tissues (9 pancreatic ductal adenocarcinomas and 3 controls) were analyzed by next-generation sequencing and microarray, respectively. Analysis confirmed differential expression of both miRNAs and mRNAs in cancerous tissue versus control, and unveiled 17401 relevant miRNA-mRNA interactions likely to occur in pancreatic cancer. They were sorted according to the degree of negative correlation between miRNA and mRNA expression. Results highlighted the importance of miR-148a and miR-21 interactions among others. Two components of the Notch signaling pathway, ADAM17 and EP300, were confirmed as miR-148a targets in MiaPaca-2 pancreatic cancer cells overexpressing miR-148a. Moreover, a CRISPR-Cas9 cellular model was generated to knock-out the expression of miR-21 in PANC-1 cells. As expected, the expression of two miRComb miR-21 predicted targets, PDCD4 and BTG2, was significantly upregulated in these cells in comparison to control PANC-1.

MicroRNA-21 promotes osteogenesis of bone marrow mesenchymal stem cells via the Smad7-Smad1/5/8-Runx2 pathway

Bone marrow mesenchymal stem cells (BMMSCs) are pluripotent stem cells, and the osteogenic differentiation of BMMSCs has been drawing attention for a long time. Bone formation is regulated by numerous molecular and cellular signaling pathways, and the differentiation of BMMSCs is controlled by a well-defined genetic program. In the present study, we isolated BMMSCs from the bone cavities of wild-type (WT) and microRNA-21 knock-out (miR-21-KO) mice and found that miR-21 was significantly upregulated during the osteogenic differentiation of BMMSCs. Under osteoinductive conditions, ALP staining and alizarin red staining showed that the bone formation of BMMSCs from miR-21-KO mice was less than that of BMMSCs from WT mice. Consistently, RT-PCR and western blotting revealed that ALP and Runx2 expression levels in miR-21-KO mice were downregulated compared with those in WT mice. Meanwhile, the calvarial bone defects of miR-21-KO mice showed less newly formed bone than did those of WT mice. Additionally, the Smad7-Smad1/5/8-Runx2 axis showed the same tendency; Smad7 overexpression and the expression of phosphorylated Smad1/5/8 complex decreased when miR-21 was knocked down. We identified a novel mechanism by which microRNA-21 (miR-21) promotes the bone formation of BMMSCs and found that this process is regulated, in part, by the Smad7-Smad1/5/8-Runx2 pathway.

Gamma Irradiation Upregulates B-cell Translocation Gene 2 to Attenuate Cell Proliferation of Lung Cancer Cells Through the JNK and NF-κB Pathways

Gamma ray can promote cancer cell apoptosis and cell cycle arrest. It is often used in the clinical treatment of tumors, including lung cancer. In this study, we aimed to explore the role of gamma ray treatment and its correlation with BTG2 in cell proliferation, apoptosis, and cell cycle arrest regulation in a lung cancer cell line. A549 cell viability, apoptosis rate, and cell cycle were investigated after gamma ray treatment. We then used siRNA for BTG2 to detect the effect of BTG2 knockdown on the progress of gamma ray-treated lung cancer cells. Finally, we investigated the signaling pathway by which gamma ray might regulate BTG2. We found that gamma ray inhibited A549 cell viability and promoted apoptosis and cell cycle arrest, while BTG2 knockdown could relieve the effect caused by gamma ray on A549 cells. Moreover, we confirmed that the effect of BTG2 partly depends on p53 expression and gamma ray-promoting BTG2 expression through the JNK/NF-κB signaling pathway. Our study assessed the possible mechanism of gamma ray in tumor treatment and also investigated the role of BTG2 in gamma ray therapy. All these findings might give a deep understanding of the effect of gamma ray on the progression of lung cancer involving BTG2.

The BTG2-PRMT1 module limits pre-B cell expansion by regulating the CDK4-Cyclin-D3 complex

Developing pre-B cells in the bone marrow alternate between proliferation and differentiation phases. We found that protein arginine methyl transferase 1 (PRMT1) and B cell translocation gene 2 (BTG2) are critical components of the pre-B cell differentiation program. The BTG2-PRMT1 module induced a cell-cycle arrest of pre-B cells that was accompanied by re-expression of Rag1 and Rag2 and the onset of immunoglobulin light chain gene rearrangements. We found that PRMT1 methylated cyclin-dependent kinase 4 (CDK4), thereby preventing the formation of a CDK4-Cyclin-D3 complex and cell cycle progression. Moreover, BTG2 in concert with PRMT1 efficiently blocked the proliferation of BCR-ABL1-transformed pre-B cells in vitro and in vivo. Our results identify a key molecular mechanism by which the BTG2-PRMT1 module regulates pre-B cell differentiation and inhibits pre-B cell leukemogenesis.

Deciphering the role of microRNA 21 in cancer stem cells (CSCs)

Irrespective of positive developments of cancer treatment, the mortality due to various cancers remains high and the mechanisms of cancer initiation and the development also remains mysterious. As we know that microRNAs are considered to be a short noncoding RNA molecules consisting of 21-25 nucleotides (nt) in length and they silence their target genes by inhibiting mRNA translation or degrading the mRNA molecules by binding to their 3'-untranslated (UTR) region and play a very important role in cancer biology. Recent evidences indicate that miR-21 is over expressed in cancer stem cells and plays a vital role in cell proliferation, apoptosis, and invasion. Even though an increased expression level of miR-21 has been observed in cancer stem cells, studies related to the role of miR-21 in cancer stem cells are limited. The main aim of this mini review is to explain the potency of miR-21 in various cancer stem cells (CSCs) and as a new target for therapeutic interventions of cancer progression.

Mechanisms for microRNAs in pathogenesis of hepatocellular carcinoma and challenges in their clinical application

Hepatocellular carcinoma (HCC) is one of the most deadly tumors worldwide, and it seriously endangers the health of people in China. Hepatocarcinogenesis is an extremely complex process that involves many risk factors. MicroRNAs (miRNAs) are a group of small, short and non-coding RNAs, and approximately one-third of human genes are regulated by miRNAs, which play important roles in tumor cell proliferation, cell cycle and apoptosis as well as tumor invasion, metastasis, and angiogenesis. Numerous studies have shown that miRNAs have a close relationship with hepatocarcinogenesis. In addition, miRNAs play a significant role in the diagnosis and therapy of HCC. In this review, we discuss the recent advances in the understanding of signaling pathways that are related to miRNAs in hepatocarcinogenesis, and the challenges faced in the clinical application of miRNAs.

Significance of microRNA 21 in gastric cancer

Despite promising developments of treatment, the mortality due to gastric cancer remains high and the mechanisms of gastric cancer initiation and the development also remains elusive. It has been reported that patients with positive serologic tests for H. pylori have a higher risk of the development of gastric cancer. microRNAs (miRNAs) are short non-coding RNA molecules consisting of 21-25 nucleotides (nt) in length. The miRNAs silence their cognate target genes by inhibiting mRNA translation or degrading the mRNA molecules by binding to their 3'-untranslated (UTR) regions and plays a very important role in cancer biology. Recent evidences indicate that miR-21 is overexpressed in tumour tissue, including gastric cancer and plays a vital role in tumour cell proliferation, apoptosis, invasion and angiogenesis. Elevated levels of miR-21 is associated with downregulation of tumour suppressor genes, such as programmed cell death 4 (PDCD4), tissue inhibitor of metalloproteinase 3, phosphatase and tensin homolog (PTEN), tropomyosin 1, ras homolog gene family member B, and maspin. Silencing of miR-21 through the use of a miR-21 inhibitor affected cancer cell viability, induced cell cycle arrest and increased chemosensitivity to anticancer agents indicating that miR-21 functions as an oncogene. Although an increased expression level of miR-21 has been observed in gastric cancer, studies related to the role of miR-21 in gastric cancer progression is very limited. The main thrust of this mini review is to explain the potency of miR-21 as a prognostic and/or diagnostic biomarker and as a new target for clinical therapeutic for interventions of gastric cancer progression.

Restoration of miR-20a expression suppresses cell proliferation, migration, and invasion in HepG2 cells

Objective

To study microRNA (miR)-20a expression in hepatocellular carcinoma (HCC) and its effects on the proliferation, migration, and invasion of HepG2.

Methods

The real-time polymerase chain reaction was used to detect the expression of miR-20a in HCC tissue and normal tissue, as well as in HCC cell lines and normal liver cells. miR-20a mimic and miR negative control (NC) were transfected into HepG2 cells. MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide) assay was used to detect cell proliferation. Annexin fluorescein isothiocyanate/propidium iodide assay was run to examine the early apoptosis of cells. Transwell chamber assay was carried out to investigate the cell invasion and migration abilities.

Results

miR-20a was lowly expressed both in HCC tissues and HCC cell lines. After transfection of exogenous miR-20 mimics, miR-20a expression in HepG2 cells was significantly increased by 61.29% compared to the blank group (P<0.01). MTT assay showed that the growth of HepG2 cells in the miR-20a mimics group was significantly inhibited, and optical density values during the 36–96 hour time period were dramatically decreased compared to the blank group (P<0.01). Apoptosis rates of the miR-20a mimics group were higher than those of the blank and NC groups (both P<0.01). The number of HCC cells after transfection by miR-20a mimics in the G1 and S phases were 15.88% and 7.89%, respectively, which were lower than in the blank and NC groups (both P<0.05). Transwell assay showed that in the miR-20a mimics group the number of cell migration and invasion were 0.459 and 0.501 times that of the blank group (both P<0.01), and the migration and inhibition rates were 54.1% and 51.4%, respectively. After closing target gene CCND1 in HepG2 cells, the number of cell migration and invasion in the small interfering (si)-CCND1 group were 0.444 and 0.435 times that of the si-NC group (P<0.05); and compared to the si-NC group, the migration and inhibition rates were 55.6% and 56.5%, respectively.

Conclusion

miR-20a can inhibit the growth, invasion, and migration of HepG2 cells, and is therefore promising as a new molecular target for diagnosis and therapy of HCC.