microRNA-23a promotes cell growth and metastasis in gastric cancer via targeting SPRY2-mediated ERK signaling

Bioactive glass selectively promotes cytotoxicity towards giant cell tumor of bone derived neoplastic stromal cells and induces MAPK signalling dependent autophagy

Giant cell tumors of bone (GCTB) are associated with massive bone destructions and high recurrence rates. In a previous study, we observed cytotoxic effects of three different compositions of bioactive glasses (BGs) towards GCTSC but not bone marrow derived stromal cells (BMSC) indicating that BGs represent promising candidates for the development of new therapeutic approaches. In the current study we aimed to investigate the molecular mechanisms that are involved in BG induced cytotoxicity. We observed, that BG treatment was not associated with any signs of apoptosis, but rather led to a strong induction of mitogen activated protein kinases (MAPK) and, as a consequence, upregulation of several transcription factors specifically in GCTSC. Genome wide gene expression profiling further revealed a set of fifteen genes that were exclusively induced in GCTSC or induced significantly stronger in GCTSC compared to BMSC. BG treatment further induced autophagy that was significantly more pronounced in GCTSC compared to BMSC and could be inhibited by MAPK inhibitors. Together with the known osteogenic properties of BGs our findings support the suitability of BGs as therapeutic agents for the treatment of GCTB. However, these data have to be verified under in vivo conditions.

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Bioactive glasses (BG) are selectively cytotoxic towards neoplastic stromal cells.

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BG induced cell death is independent from apoptosis.

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BG activates mitogen activated protein kinases and transcription factors.

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BG trigger differential gene expression in neoplastic versus normal cells.

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BG induce autophagy.

Overexpression of miR-331 Indicates Poor Prognosis and Promotes Progression of Breast Cancer

BACKGROUND

With the increasing number of cases of breast cancer every year, the exploration of novel biomarkers has drawn attention. miR-331 has been demonstrated to play a role in various cancers, but its role in breast cancer is still unknown.

METHODS

In this study, we included 121 patients with breast cancer treated at Affiliated Hospital of Weifang Medical University. Breast cancer tissues and adjacent normal tissues were collected during the surgery. The expression of miR-331 in breast cancer tissues and cell lines was detected by qRT-PCR assay. Then, with the help of Kaplan-Meier survival and Cox regression analyses, the role of miR-331 in the prognosis of breast cancer was analyzed. Finally, the effect of miR-331 on cell proliferation, migration, and invasion was investigated with CCK-8 assay and transwell assay.

RESULTS

miR-331 was significantly upregulated in breast cancer tissues compared with normal tissues. The overexpression of miR-331 was associated with lymph node metastasis, TNM stage, and poor prognosis. From the results of Cox regression analyses, it was found that miR-331 served as an independent indicator in the prognosis of breast cancer. In addition, miR-331 was also found to be upregulated in breast cancer cells, which promoted cell proliferation, migration, and invasion of breast cancer.

CONCLUSION

As shown from our data, miR-331 may be a potential prognostic biomarker in breast cancer. Moreover, the development and progression of breast cancer may involve miR-331. These findings suggest a novel therapeutic target for the treatment of breast cancer.

Gastric Cancer Cell-Derived Exosomal microRNA-23a Promotes Angiogenesis by Targeting PTEN

Hypoxia-exposed lung cancer-released exosomal microRNA-23a (miR-23a) has been shown to enhance angiogenesis as well as vascular permeability, contributing to the close correlation between exosomal miR-23a and tumorigenesis. The current study aimed to investigate whether gastric cancer (GC) cell-derived exosomal miR-23a could induce angiogenesis and to elucidate the potential mechanisms associated with the process. Differentially expressed miRNAs in GC were initially screened from the Gene Expression Omnibus database. Target genes were selected following miRNA-mRNA prediction and subsequently verified by dual luciferase reporter assay. RT-qPCR was conducted to detect miR-23a and PTEN expression in GC tissues, cells and exosomes. Human umbilical venous endothelial cells (HUVECs) were co-cultured with GC cell-derived exosomes to assess the angiogenesis mediated by exosomes in vitro. Additionally, PTEN was overexpressed in HUVECs to analyze the mechanism by which miR-23a regulates angiogenesis. miR-23a was highly expressed in GC tissues and cells and GC cell-derived exosomes. Angiogenesis was promoted by the co-culture of HUVECs and GC cells-derived exosomes, as evidenced by the increased expression of VEGF but decreased expression of TSP-1. PTEN was targeted by miR-23a and was lowly expressed in GC tissues. In a co-culture system, miR-23a carried by GC cells-derived exosomes promoted angiogenesis via the repression of PTEN. Collectively, GC cell-derived exosomal miR-23a could promote angiogenesis and provide blood supply for growth of GC cells. This study contributes to advancement of miRNA-targeted therapeutics.

miR-140-3p exhibits repressive functions on preosteoblast viability and differentiation by downregulating MCF2L in osteoporosis

Previous research manifested that miR-140-3p was a latent biomarker for osteoporosis. Nevertheless, the mechanism of miR-140-3p in osteoporosis is still not clear and needs ulteriorly studying. The purpose of our paper was to ulteriorly probe the underlying mechanism of miR-140-3p on osteoporosis. Firstly, based on the data acquired from GEO database, we found that miR-140-3p was highly expressed; meanwhile, MCF2L was lowly expressed in osteoporosis patients. Upregulation/downregulation of miR-140-3p by miR-140-3p mimic/inhibitor restrained/promoted MC3T3-E1 cell viability and differentiation. However, miR-140-3p over-expression/downregulation accelerated/repressed MC3T3-E1 cell apoptosis. MCF2L was forecasted as a target of miR-140-3p by miRanda, miRWalk, and TargetScan miRNA target gene prediction software. Luciferase reporter assay confirmed that MCF2L could be directly targeted by miR-140-3p. Moreover, we identified that the expression of MCF2L was negatively regulated by miR-140-3p. From rescue assays, we discovered that knockdown of MCF2L weakened the promoting influence of miR-140-3p ablation on MC3T3-E1 cell viability and differentiation, and receded the suppressing impact of miR-140-3p reduction on MC3T3-E1 cell apoptosis. Above all, this research disclosed that miR-140-3p repressed preosteoblast viability and differentiation while promoted preosteoblast apoptosis via targeting MCF2L. Our discoveries might afford a theoretical basis of developing a latent novel target for osteoporosis therapy.

[Plasma miRNA-23a and miRNA-451 as candidate biomarkers for early diagnosis of nonsmall cell lung cancer: a case-control study]

OBJECTIVE

To study the value of plasma miRNA23-a and miRNA-451 as potential biomarkers for early diagnosis of non-small cell lung cancer (NSCLC).

METHODS

Fifty patients with NSCLC and 50 healthy control subjects were recruited for testing the plasma levels of miRNA23-a and miRNA-451 and their expression levels in the tumor tissues using qRT-PCR. The correlations of the plasma levels of miRNA23-a and miRNA-451 with their expressions in the tumor tissues were analyzed. The diagnostic power of CEA, miRNA23-a and miRNA-451 for NSCLC was evaluated using the receiver-operating characteristics (ROC) curves and the area under the ROC curves (AUC). In the NSCLC cell line A549, we tested the effect of inhibition of miRNA-23a and miRNA-451 on the expression levels of SPRY2 and MIF mRNA using qRT-PCR.

RESULTS

The expression levels of miRNA-23a and miRNA-451 in NSCLC tissues was significantly associated with smoking, tumor size, lymph node metastasis and TNM stage (P < 0.05). Compared with those in the control group, miRNA-23a level was significantly increased while miRNA-451 was significantly down-regulated in the tumor tissues and plasma of NSCLC patients. The plasma levels of miRNA-23a and miRNA-45 were strongly correlated with their expression levels in the tumor tissues. ROC analysis showed that for the diagnosis of NSCLC, the AUC, sensitivity and specificity of either miRNA-23a or miRNA-451 were significantly higher than those of CEA (P < 0.05). The combination of miRNA23-a and miRNA-451 markedly improved the AUC (0.900), sensitivity (78%) and specificity (86%) for the diagnosis. In A549 cells, inhibition of miRNA23-a and miRNA-451 resulted in significantly increased expression levels of SPRY2 mRNA and MIF mRNA, respectively.

CONCLUSIONS

miRNA-23a and miRNA-451 can be used as potential biomarkers for early diagnosis of NSCLC, and their combined detection can be more effective for the diagnosis.

Cadmium induces A549 cell migration and invasion by activating ERK

Cadmium (Cd) is an established carcinogen that is involved in the progression of lung cancer. However, the mechanisms underlying this Cd-induced process have yet to be fully elucidated. The present study explored the potential roles of phosphorylated (p)-ERK in the Cd-induced migration and invasion of lung cancer cells. An MTT assay was performed to evaluate cell viability whilst western blot analysis and reverse transcription-quantitative PCR were used to detect the expression of protein and mRNA, respectively. Migration and invasion assays were performed to assess cell migratory and invasive abilities. The results demonstrated that exposure to Cd increased the expression of p-ERK in A549 cells. Cd also enhanced the migration and invasion of A549 cells, which could be blocked via U0126 treatment (an inhibitor of mitogen activated protein kinase). In addition, it was identified that Cd-induced expression of matrix metalloproteinases 2 mRNA was mediated by p-ERK. In conclusion, the present findings indicated that Cd induced A549 cell migration and invasion by activating ERK, and it was hypothesized that p-ERK could serve as a target in the clinical treatment of Cd-induced lung cancer.

The Sprouty/Spred family as tumor suppressors: Coming of age

The Ras/Raf/ERK pathway is one of the most frequently dysregulated signaling pathways in various cancers. In some such cancers, Ras and Raf are hotspots for mutations, which cause continuous activation of this pathway. However, in some other cancers, it is known that negative regulators of the Ras/Raf/ERK pathway are responsible for uncontrolled activation. The Sprouty/Spred family is broadly recognized as important negative regulators of the Ras/Raf/ERK pathway, and its expression is downregulated in many malignancies, leading to hyperactivation of the Ras/Raf/ERK pathway. After the discovery of this family, intensive research investigated the mechanism by which it suppresses the Ras/Raf/ERK pathway and its roles in developmental and pathophysiological processes. In this review, we discuss the complicated roles of the Sprouty/Spred family in tumor initiation, promotion, and progression and its future therapeutic potential.

MicroRNA-23a depletion promotes apoptosis of ovarian cancer stem cell and inhibits cell migration by targeting DLG2

Ovarian cancer (OC) is xenogeneic that is influenced by many generated factors related to epigenetic factors to accelerate tumor metastasis. This study was conducted with the objective of investigating the effect of microRNA-23a-3p (miR-23a) on the biological characteristics of OC stem cells by targeting discs large homolog 2 (DLG2). OC-related differentially expressed genes were screened by microarray-based gene expression analysis, after which a list of miRNAs that regulate the genes was predicted. In total, 50 patients diagnosed with OC were enrolled in this study. DLG2 positive protein expression was measured in OC tissues. The interaction between DLG2 and miR-23a was predicted and analyzed through luciferase activity measurement. With the intervention of miR-23a and/or DLG2 expression in OC stem cells, the expression of miR-23a, DLG2, Bax, Bcl-2, Oct-4, and Nanog was determined. Afterward, different cell experiments were conducted to examine the regulation effect of miR-23a in OC stem cells. Tumor formation in vivo was also evaluated in nude mice. DLG2 had low expression in OC. The results showed that there was a decrease in the expression of Bcl-2, Oct-4, and Nanog, while DLG2 and Bax were increased as a result of miR-23a depletion. In addition, when miR-23a was suppressed, cell viability, migration, invasion, cloning, and renewal abilities of OC stem cells were decreased, while apoptosis ability was enhanced. As a target gene of miR-23a, DLG2 downregulation reversed the suppressive function of miR-23a in the inhibition of OC development. Finally, in vivo experiment verified that miR-23a downregulation restrained the tumor growth in OC stem cells. In conclusion, our findings suggested that the inhibition of miR-23a results in the suppression of OC progression by releasing DLG2, which provides new understanding on the potential therapeutic effect of miR-23a inhibition in OC patients.

microRNA-23a in Human Cancer: Its Roles, Mechanisms and Therapeutic Relevance

microRNA-23a (miR-23a) is one of the most extensively studied miRNAs in different types of human cancer, and plays various roles in the initiation, progression, and treatment of tumors. Here, we comprehensively summarize and discuss the recent findings about the role of miR-23a in cancer. The differential expression of tissue miR-23a was reported, potentially indicating cancer stages, angiogenesis, and metastasis. miR-23a in human biofluid, such as plasma and salivary fluid, may be a sensitive and specific marker for early diagnosis of cancer. Tissue and circulating miR-23a serves as a prognostic factor for cancer patient survival, as well as a predictive factor for response to anti-tumor treatment. The direct and indirect regulation of miR-23a on multiple gene expression and signaling transduction mediates carcinogenesis, tumor proliferation, survival, cell migration and invasion, as well as the response to anti-tumor treatment. Tumor cell-derived miR-23a regulates the microenvironment of human cancer through manipulating both immune function and tumor vascular development. Several transcriptional and epigenetic factors may contribute to the dysregulation of miR-23a in cancer. This evidence highlights the essential role of miR-23a in the application of cancer diagnosis, prognosis, and treatment.