MiR-133b is down-regulated in human osteosarcoma and inhibits osteosarcoma cells proliferation, migration and invasion, and promotes apoptosis

Focal adhesion kinase as a new player in the biology of onco-hematological diseases: the starting evidence

Focal adhesion kinase (FAK) is a non-receptor tyrosine kinase mainly found in the focal adhesion regions of the plasma membrane and it has a crucial role in migration and the remodeling of cellular morphology. FAK is also linked to several aspects of cancer biology, from cytokine production to angiogenesis, drug resistance, invasion, and metastasis, as well as epithelial-to-mesenchymal transition. The gene locus of FAK is frequently amplified in several human tumors, thus causing FAK overexpression in several cancers. Furthermore, FAK can influence extracellular matrix production and exosome secretion through cancer-associated fibroblasts, thus it has an important role in tumor microenvironment regulation. Although the role of FAK in solid tumors is well known, its importance in onco-hematological diseases remains poorly explored. This review collects studies related to FAK significance in onco-hematological diseases and their microenvironments. Overall, the importance of FAK in blood tumors is increasingly evident, but further research is required to confirm it as a new therapeutic target in hematological contexts.

Mefenamic acid exhibits antitumor activity against osteosarcoma by impeding cell growth and prompting apoptosis in human osteosarcoma cells and xenograft mice model

The study investigates the anticancer activity of mefenamic acid against osteosarcoma, shedding light on its underlying mechanisms and therapeutic potential. Mefenamic acid exhibited robust inhibitory effects on the proliferation of MG-63, HOS, and H2OS osteosarcoma cells in a dose-dependent manner. Moreover, mefenamic acid induced cellular toxicity in MG63 cells, as evidenced by LDH leakage, reflecting its cytotoxic impact. Furthermore, mefenamic acid effectively suppressed the migration and invasion of MG-63 cells. Mechanistically, mefenamic acid induced apoptosis in MG-63 cells through mitochondrial depolarization, activation of caspase-dependent pathways, and modulation of the Bcl-2/Bax axis. Additionally, mefenamic acid promoted autophagy and inhibited the PI3K/Akt/mTOR pathway, further contributing to its antitumor effects. The molecular docking studies provide compelling evidence that mefenamic acid interacts specifically and strongly with key proteins in the PI3K/AKT/mTOR pathway, suggesting a novel mechanism by which mefenamic acid could exert anti-osteosarcoma effects. In vivo studies using a xenograft mouse model demonstrated significant inhibition of MG-63 tumor growth without adverse effects, supporting the translational potential of mefenamic acid as a safe and effective therapeutic agent against osteosarcoma. Immunohistochemistry staining corroborated the in vivo findings, highlighting mefenamic acid's ability to suppress tumor proliferation and inhibit the PI3K/AKT/mTOR pathway within the tumor microenvironment. Collectively, these results underscore the promising therapeutic implications of mefenamic acid in combating osteosarcoma, warranting further investigation for clinical translation and development.

The Landscape of microRNAs in Bone Tumor: A Comprehensive Review in Recent Studies

Cancer, the second greatest cause of mortality worldwide, frequently causes bone metastases in patients with advanced-stage carcinomas such as prostate, breast, and lung cancer. The existence of these metastases contributes to the occurrence of skeletal-related events (SREs), which are defined by excessive pain, pathological fractures, hypercalcemia, and spinal cord compression. These injurious incidents leave uncomfortably in each of the cancer patient's life quality. Primary bone cancers, including osteosarcoma (OS), chondrosarcoma (CS), and Ewing's sarcoma (ES), have unclear origins. MicroRNA (miRNA) expression patterns have been changed in primary bone cancers such as OS, CS, and ES, indicating a role in tumor development, invasion, metastasis, and treatment response. These miRNAs are persistent in circulation and exhibit distinct patterns in many forms of bone tumors, making them potential biomarkers for early detection and treatment of such diseases. Given their crucial regulatory functions in various biological processes and conditions, including cancer, this study aims to look at miRNAs' activities and possible contributions to bone malignancies, focusing on OS, CS, and ES. In conclusion, miRNAs are valuable tools for diagnosing, monitoring, and predicting OS, CS, and ES outcomes. Further research is required to fully comprehend the intricate involvement of miRNAs in these bone cancers and to develop effective miRNA-based treatments.

MicroRNA-455-3p inhibits osteosarcoma progression via HSF1 downregulation

OBJECTIVE

This study was conducted to dissect the role and potential mechanism of microRNA (miR)-455-3p on osteosarcoma (OS) development.

METHODS

miR-455-3p and HSF1 expression in OS tissues were detected by RT-qPCR and western blot. Later, gain- and loss-of-function assays were implemented in OS cells U-2OS and MNNG. The expression of apoptosis-related genes was measured by RT-qPCR and western blot. MTT, Transwell, scratch test, and flow cytometry were utilized to test OS cell viability, invasion, migration, and apoptosis. The targeting relationship between miR-455-3p and HSF1 was assessed with a dual-luciferase reporter gene assay. The transplantation tumor experiment in nude mice was utilized for in vivo confirmation.

RESULTS

Downregulated miR-455-3p and upregulated HSF1 were displayed in OS tissues and cells. Mechanistically, miR-455-3p negatively targeted HSF1. MiR-455-3p inhibition or HSF1 overexpression increased MNNG and U-2OS cell proliferative, invasive, and migrating capabilities, while diminishing U-2OS cell apoptosis. Moreover, HSF1 overexpression negated the impacts of miR-455-3p upregulation on OS cell proliferative, invasive, migrating, and apoptotic abilities. Likewise, overexpressing miR-455-3p curtailed the growth of transplanted OS tumors through HSF1 repression.

CONCLUSION

MiR-455-3p inhibits the development of OS cells by downregulating HSF1, highlighting the possibility of miR-455-3p as an innovative indicator of prognosis and a therapeutic target for OS.

Functional role of MicroRNA/PI3K/AKT axis in osteosarcoma

Osteosarcoma (OS) is a primary malignant bone tumor that occurs in children and adolescents, and the PI3K/AKT pathway is overactivated in most OS patients. MicroRNAs (miRNAs) are highly conserved endogenous non-protein-coding RNAs that can regulate gene expression by repressing mRNA translation or degrading mRNA. MiRNAs are enriched in the PI3K/AKT pathway, and aberrant PI3K/AKT pathway activation is involved in the development of osteosarcoma. There is increasing evidence that miRNAs can regulate the biological functions of cells by regulating the PI3K/AKT pathway. MiRNA/PI3K/AKT axis can regulate the expression of osteosarcoma-related genes and then regulate cancer progression. MiRNA expression associated with PI3K/AKT pathway is also clearly associated with many clinical features. In addition, PI3K/AKT pathway-associated miRNAs are potential biomarkers for osteosarcoma diagnosis, treatment and prognostic assessment. This article reviews recent research advances on the role and clinical application of PI3K/AKT pathway and miRNA/PI3K/AKT axis in the development of osteosarcoma.

Vascular Niche Facilitates Acquired Drug Resistance to c-Met Inhibitor in Originally Sensitive Osteosarcoma Cells

Osteosarcoma (OS) is the most common primary bone tumor in children and adolescents characterized by drug resistance and poor prognosis. As one of the key oncogenes, c-Met is recognized as a promising therapeutic target for OS. In this report, we show that c-Met inhibitor PF02341066 specifically killed OS cells with highly phosphorylated c-Met in vitro. However, the inhibitory effect of PF02341066 was abrogated in vivo due to interference from the vascular niche. OS cells adjacent to microvessels or forming vascular mimicry suppressed c-Met expression and phosphorylation. Moreover, VEGFR2 was activated in OS cells and associated with acquired drug resistance. Dual targeting of c-Met and VEGFR2 could effectively shrink the tumor size in a xenograft model. c-Met-targeted therapy combined with VEGFR2 inhibition might be beneficial to achieve an ideal therapeutic effect in OS patients. Together, our results confirm the pivotal role of tumor heterogeneity and the microenvironment in drug response and reveal the molecular mechanism underlying acquired drug resistance to c-Met-targeted therapy.

MicroRNA-133 suppresses cell viability and migration of rheumatoid arthritis fibroblast-like synoviocytes by down-regulation of MET, EGFR, and FSCN1 expression

Aberrant proliferation and migration of fibroblast-like synoviocytes (FLS) are major characteristics of rheumatoid arthritis (RA). MicroRNA-133 (miR-133) is a tumor-suppressive miRNA that targets various genes responsive for cell proliferation and migration. The aim of this study was to examine the effect of miR-133 on RA FLS. A high throughput miRNA microarray was performed in synovium from mice with collagen-induced arthritis (CIA). Expression levels of miR-133 and the putative targets were determined in synovium and FLS from patients with RA and mice with CIA. Overexpression of miR-133 in RA FLS was performed by lentiviral vector-mediated transfer of precursor miRNA (pre-miR). The expression of miR-133a/b was decreased in the joint tissue and FLS of CIA mice, as determined by miRNA array and qRT-PCR. Down-regulation of miR-133a/b expression could also be observed in synovium and FLS from patients with RA. Overexpression of miR-133 reduced cell viability and migration of RA FLS, with decreased levels of FSCN1, EGFR, and MET. Our findings demonstrated the inhibitory effects of miR-133 on FLS viability and migration, and might contribute to the pharmacologic development of miR-133 therapeutics in patients with RA.

Molecular mechanism of microRNAs regulating apoptosis in osteosarcoma

Osteosarcoma is a primary malignant bone tumor with no effective treatment. Apoptosis, one of the programmed cell death, is any pathological form of cell death mediated by intracellular processes. Under the pathological state, the de-regulated regulation of apoptosis can disrupt the balance between cell proliferation and death, causing osteosarcoma proliferation and metastasis. As carcinogenic or tumor suppressor factors, microRNAs (miRNAs) regulate apoptosis of osteosarcoma cells by regulating apoptosis-related genes and apoptosis-related signaling pathways, such as mitochondrial apoptosis pathway, death receptor pathway, and endoplasmic reticulum pathway. Meanwhile as these abnormal miRNAs can be stored and transported by exosomes, detecting exosomes can be seen an effective method to diagnose osteosarcoma in the early stage. This review provides the current knowledge of miRNAs and their target genes related to the apoptosis of osteosarcoma, summarizes abnormal expression and regulation of miRNAs and signaling pathways in osteosarcoma and prospects the detection of exosome as a method for early diagnosis of osteosarcoma.

The Role of miRNA in the Pathophysiology of Neuroendocrine Tumors

Neuroendocrine tumors (NETs) represent a tumor group that is both rare and heterogeneous. Prognosis is largely determined by the tumor grading and the site of the primary tumor and metastases. Despite intensive research efforts, only modest advances in diagnostic and therapeutic approaches have been achieved in recent years. For patients with non-respectable tumor stages, prognosis is poor. In this context, the development of novel diagnostic tools for early detection of NETs and prediction of tumor response to therapy as well as estimation of the overall prognosis would greatly improve the clinical management of NETs. However, identification of novel diagnostic molecules is hampered by an inadequate understanding of the pathophysiology of neuroendocrine malignancies. It has recently been demonstrated that microRNA (miRNA), a family of small RNA molecules with an established role in the pathophysiology of quite different cancer entities, may also play a role as a biomarker. Here, we summarize the available knowledge on the role of miRNAs in the development of NET and highlight their potential use as serum-based biomarkers in the context of this disease. We discuss important challenges currently preventing their use in clinical routine and give an outlook on future directions of miRNA research in NET.

Myeloid cell leukemia 1 (MCL-1): Structural characteristics and application in cancer therapy

Apoptosis, a major hallmark of cancer cells, regulates cellular fate and homeostasis. BCL-2 (B-cell CLL/Lymphoma 2) protein family is popularly known to mediate the intrinsic mode of apoptosis, of which MCL-1 is a crucial member. Myeloid cell leukemia 1 (MCL-1) is an anti-apoptotic oncoprotein and one of the most investigated members of the BCL-2 family. It is commonly known to be genetically altered, aberrantly overexpressed, and primarily associated with drug resistance in various human cancers. Recent advancements in the development of selective MCL-1 inhibitors and evaluating their effectiveness in cancer treatment establish its popularity as a molecular target. The overall aim is the selective induction of apoptosis in cancer cells by using a single or combination of BCL-2 family inhibitors. Delineating the precise molecular mechanisms associated with MCL-1-mediated cancer progression will certainly improve the efficacy of clinical interventions aimed at MCL-1 and hence patient survival. This review is structured to highlight the structural characteristics of MCL-1, its specific interactions with NOXA, MCL-1-regulatory microRNAs, and at the same time focus on the emerging therapeutic strategies targeting our protein of interest (MCL-1), alone or in combination with other treatments.

miR-378c suppresses Wilms tumor development via negatively regulating CAMKK2

Wilms tumor is a rare kidney malignancy primarily developed in children. Treatment for Wilms tumor includes surgery, radiotherapy, and chemotherapy. Recent studies have demonstrated that microRNAs (miRNAs) play important roles in regulating Wilms tumor development. In this study, we aimed to elucidate the expression and function of miR-378c in Wilms tumor. Quantitative real-time PCR (qRT-PCR) results showed that miR-378c was downregulated in Wilms tumor tissues and cell lines. Functionally, further CCK-8, would healing, and transwell assays revealed that overexpression of miR-378c impaired Wilms tumor cell growth and metastasis in vitro. In addition, xenograft assay showed that miR-378c overexpression inhibited Wilms tumor development in vivo. Mechanistically, luciferase reporter assay confirmed that miR-378c directly targets CAMKK2 in Wilms tumor. qRT-PCR and western blot assays demonstrated that CAMKK2 was highly expressed in Wilms tumor tissues and cell lines. Rescue experiments were performed to further evaluate the functional relationship between miR-378c and CAMKK2. Overexpression of miR-378c suppressed Wilms tumor cell metastasis via negatively regulating CAMKK2 expression. Consistently, inhibition of miR-378c enhanced Wilms tumor cell malignancy behavior via augmenting CAMKK2 expression, which could be abrogated by CAMKK2 knockdown. In summary, our findings suggest that miR-378c inhibits the development and metastasis of Wilms tumor via negatively regulating CAMKK2 expression, which could be utilized to develop new therapy strategy.

Identifying the Potential Differentially Expressed miRNAs and mRNAs in Osteonecrosis of the Femoral Head Based on Integrated Analysis

Purpose

Osteonecrosis of the femoral head is a common disease of the hip that leads to severe pain or joint disability. We aimed to identify potential differentially expressed miRNAs and mRNAs in osteonecrosis of the femoral head.

Methods

The data of miRNA and mRNA were firstly downloaded from the database. Secondly, the regulatory network of miRNAs-mRNAs was constructed, followed by function annotation of mRNAs. Thirdly, an in vitro experiment was applied to validate the expression of miRNAs and targeted mRNAs. Finally, GSE123568 dataset was used for electronic validation and diagnostic analysis of targeted mRNAs.

Results

Several regulatory interaction pairs between miRNA and mRNAs were identified, such as hsa-miR-378c-WNT3A/DACT1/CSF1, hsa-let-7a-5p-RCAN2/IL9R, hsa-miR-28-5p-RELA, hsa-miR-3200-5p-RELN, and hsa-miR-532-5p-CLDN18/CLDN10. Interestingly, CLDN10, CLDN18, CSF1, DACT1, IL9R, RCAN2, RELN, and WNT3A had the diagnostic value for osteonecrosis of the femoral head. Wnt signaling pathway (involved WNT3A), chemokine signaling pathway (involved RELA), focal adhesion and ECM-receptor interaction (involved RELN), cell adhesion molecules (CAMs) (involved CLDN18 and CLDN10), cytokine-cytokine receptor interaction, and hematopoietic cell lineage (involved CSF1 and IL9R) were identified.

Conclusion

The identified differentially expressed miRNAs and mRNAs may be involved in the pathology of osteonecrosis of the femoral head.

Blood levels of microRNAs associated with ischemic heart disease differ between Austrians and Japanese: a pilot study

Mortality from ischemic heart disease (IHD) is significantly lower in Japan than in Western countries. The purpose of this study was to investigate differences in circulating microRNA (miRNA) levels related to IHD in Austrians and Japanese. Participants were middle-aged healthy male Austrians (n = 20) and Japanese (n = 20). Total miRNAs in serum from each participant were analyzed using the 3D-Gene miRNA Oligo chip. Twenty-one miRNAs, previously reported as associated with IHD, were compared between Austrians and Japanese. The expression levels of miR-106a-5p, miR-135a-3p, miR-150-3p, miR-16-5p, miR-17-5p. miR-191-5p, miR-320b, miR-451a, miR-486-5p, miR-663b, and miR-92a-3p were significantly higher, while the miR-2861 expression level was significantly lower in Austrians as compared to Japanese. Both in Austrians and Japanese, there were significant positive correlations between serum expression levels of each pair of the above miRNAs except for miR-2861. The expression level of miR-2861 showed significant positive correlations with the expression levels of miR-106a-5p, miR-150-3p, miR-17-5p, miR-486-5p, miR-663b and miR-92a-3p in Austrians but not in Japanese. In pathway analysis, proinflammatory cytokine production in foam cells and collagen synthesis in vascular smooth muscle cells were associated with differentially expressed miRNAs. Difference in miRNA levels may contribute to lower cardiovascular risk in Japan than in Western countries.

MicroRNAs signatures, bioinformatics analysis of miRNAs, miRNA mimics and antagonists, and miRNA therapeutics in osteosarcoma

MicroRNAs (miRNAs) involved in key signaling pathways and aggressive phenotypes of osteosarcoma (OS) was discussed, including PI3K/AKT/MTOR, MTOR AND RAF-1 signaling, tumor suppressor P53- linked miRNAs, NOTCH- related miRNAs, miRNA -15/16 cluster, apoptosis related miRNAs, invasion-metastasis-related miRNAs, and 14Q32-associated miRNAs cluster. Herrin, we discussed insights into the targeted therapies including miRNAs (i.e., tumor-suppressive miRNAs and oncomiRNAs). Using bioinformatics tools, the interaction network of all OS-associated miRNAs and their targets was also depicted.

BCL-w: apoptotic and non-apoptotic role in health and disease

The BCL-2 family of proteins integrates signals that trigger either cell survival or apoptosis. The balance between pro-survival and pro-apoptotic proteins is important for tissue development and homeostasis, while impaired apoptosis contributes to several pathologies and can be a barrier against effective treatment. BCL-w is an anti-apoptotic protein that shares a sequence similarity with BCL-X_L, and exhibits a high conformational flexibility. BCL-w level is controlled by a number of signaling pathways, and the repertoire of transcriptional regulators largely depends on the cellular and developmental context. As only a few disease-relevant genetic alterations of BCL2L2 have been identified, increased levels of BCL-w might be a consequence of abnormal activation of signaling cascades involved in the regulation of BCL-w expression. In addition, BCL-w transcript is a target of a plethora of miRNAs. Besides its originally recognized pro-survival function during spermatogenesis, BCL-w has been envisaged in different types of normal and diseased cells as an anti-apoptotic protein. BCL-w contributes to survival of senescent and drug-resistant cells. Its non-apoptotic role in the promotion of cell migration and invasion has also been elucidated. Growing evidence indicates that a high BCL-w level can be therapeutically relevant in neurodegenerative disorders, neuron dysfunctions and after small intestinal resection, whereas BCL-w inhibition can be beneficial for cancer patients. Although several drugs and natural compounds can bi-directionally affect BCL-w level, agents that selectively target BCL-w are not yet available. This review discusses current knowledge on the role of BCL-w in health, non-cancerous diseases and cancer.

Downregulation of miRNA-663b protects against hypoxia-induced injury in cardiomyocytes by targeting BCL2L1

In the present study, the role of microRNA-663b (miR-663b) in cardiomyocyte injury was examined. Reverse transcription-quantitative PCR (RT-qPCR) was performed to detect miR-663b expression in hypoxia-induced H9c2 cells. The results revealed that miR-663b expression was significantly upregulated in hypoxia-induced H9c2 cells compared with control cells. TargetScan analysis and dual-luciferase reporter assays demonstrated that miR-663b directly targeted the B-cell lymphoma 2 like 1 (BCL2L1) gene. RT-qPCR and western blotting data indicated that BCL2L1 expression was significantly downregulated in hypoxia-induced H9c2 cells compared with control cells. Under hypoxic conditions, H9c2 cells were transfected with miR-663b inhibitor, inhibitor control, miR-663b inhibitor + control small interfering (si)RNA or miR-663b inhibitor + BCL2L1-siRNA for 48 h. ELISA against creatine kinase-muscle/brain (CK-MB) and cardiac troponin 1 (cTnI) demonstrated that the miR-663b inhibitor reduced CK-MD and cTnI release and increased mitochondrial viability when compared with hypoxia-treated cells. Additionally, the miR-663b inhibitor significantly increased H9c2 cell viability and decreased cell apoptosis under hypoxic conditions. The results of ELISA further revealed that the miR-663b inhibitor decreased the release of various inflammatory factors, including tumour necrosis factor α, interleukin (IL) 1β and IL-6 in H9c2 cells under hypoxic conditions. These changes were reversed following BCL2L1 knockdown. In conclusion, miR-663b inhibition protected cardiomyocytes against hypoxia-induced injury by targeting BCL2L1 and may potentially be a novel target for the treatment of patients with myocardial infarction.

Rs1894720 polymorphism is associated with the risk of age-related cataract by regulating the proliferation of epithelial cells in the lens via the signalling pathway of MIAT/miR-26b/BCL2L2

INTRODUCTION

Cataracts caused by old age are one of the most frequent causes for blindness and poor vision worldwide. In this study, we aimed to clarify the possible role of rs1894720 polymorphism in the pathogenesis of age-related cataract.

MATERIAL AND METHODS

Rs1894720 polymorphism genotype was detected by TaqMan. Bioinformatics analysis, luciferase assay, real-time PCR, western blot, and protein density analysis were conducted to establish the correlations between MIAT and miR-26b as well as between BCL2L2 and miR-26b. Flow cytometry and MTT assay were also performed to observe the effect of MIAT/miR-26b/BCL2L2 signalling pathway on the status of cell apoptosis and viability.

RESULTS

MIAT functioned as an endogenous competing RNA to sponge miR-26b. In addition, BCL2L2 was identified as a target of miR-26b. Therefore, the expression of miR-26b was obviously suppressed by MIAT or anti-miR-26b, while the mRNA and protein expression of BCL2L2 was up-regulated in the presence of MIAT or anti-miR-26b. Moreover, the positive effect of MIAT on BCL2L2 expression was exerted via inhibition of the expression of miR-26b. In addition, the cells transfected with MIAT or anti-miR-26b showed suppressed expression of caspase-3 and reduced apoptosis index but higher cell viability, indicating that MIAT could suppress cell apoptosis via inhibition of miR-26b expression. Furthermore, the subjects carrying the GT and TT genotypes of single-nucleotide polymorphism (SNP) rs1894720 were associated with a higher risk of age-related cataracts, as indicated by their odds ratio (OR) and p-values.

CONCLUSIONS

Rs1894720 SNP could down-regulate the expression of MIAT, thus leading to reduced BCL2L2 expression and enhanced epithelial cell apoptosis in the lens, eventually increasing the incidence of age-related cataract.

Receptor Tyrosine Kinases in Osteosarcoma: 2019 Update

The primary conclusions of our 2014 contribution to this series were as follows: Multiple receptor tyrosine kinases (RTKs) likely contribute to aggressive phenotypes in osteosarcoma and, therefore, inhibition of multiple RTKs is likely necessary for successful clinical outcomes. Inhibition of multiple RTKs may also be useful to overcome resistance to inhibitors of individual RTKs as well as resistance to conventional chemotherapies. Different combinations of RTKs are likely important in individual patients. AXL, EPHB2, FGFR2, IGF1R, and RET were identified as promising therapeutic targets by our in vitro phosphoproteomic/siRNA screen of 42 RTKs in the highly metastatic LM7 and 143B human osteosarcoma cell lines. This chapter is intended to provide an update on these topics as well as the large number of osteosarcoma clinical studies of inhibitors of multiple tyrosine kinases (multi-TKIs) that were recently published.

Inhibition of miR-378a-3p by Inflammation Enhances IL-33 Levels: A Novel Mechanism of Alarmin Modulation in Ulcerative Colitis

Ulcerative colitis (UC) is an inflammatory bowel disease (IBD) characterized by mucosa damage associated with an uncontrolled inflammatory response. This immunological impairment leads to altered inflammatory mediators such as IL-33, which is shown to increase in the mucosa of active UC (aUC) patients. MicroRNAs present a distorted feature in inflamed colonic mucosa and are potential IL-33 regulating candidates in UC. Therefore, we studied the microRNA and mRNA profiles in inflamed colonic samples of UC patients, evaluating the effect of a microRNA (selected by in silico analysis and its expression in UC patients), on IL-33 under inflammatory conditions. We found that inflamed mucosa (n = 8) showed increased expression of 40 microRNAs and 2,120 mRNAs, while 49 microRNAs and 1,734 mRNAs were decreased, as determined by microarrays. In particular, IL-33 mRNA showed a 3.8-fold increase and eight members of a microRNA family (miR-378), which targets IL-33 mRNA in the 3'UTR, were decreased (-3.9 to -3.0 times). We selected three members of the miR-378 family (miR-378a-3p, miR-422a, and miR-378c) according to background information and interaction energy analysis, for further correlation analyses with IL-33 expression through qPCR and ELISA, respectively. We determined that aUC (n = 24) showed high IL-33 levels, and decreased expression of miR-378a-3p and miR-422a compared to inactive UC (n = 10) and controls (n = 6). Moreover, both microRNAs were inversely correlated with IL-33 expression, while miR-378c does not show a significant difference. To evaluate the effect of TNFα on the studied microRNAs, aUC patients with anti-TNF therapy were compared to aUC receiving other treatments. The levels of miR-378a-3p and miR-378c were higher in aUC patients with anti-TNF. Based on these findings, we selected miR-378a-3p to exploring the molecular mechanism involved by in vitro assays, showing that over-expression of miR-378a-3p decreased the levels of an IL-33 target sequence β-gal-reporter gene in HEK293 cells. Stable miR-378a-3p over-expression/inhibition inversely modulated IL-33 content and altered viability of HT-29 cells. Additionally, in an inflammatory context, TNFα decreased miR-378a-3p levels in HT-29 cells enhancing IL-33 expression. Together, our results propose a regulatory mechanism of IL-33 expression exerted by miR-378a-3p in an inflammatory environment, contributing to the understanding of UC pathogenesis.

miR-133b suppresses colorectal cancer cell stemness and chemoresistance by targeting methyltransferase DOT1L

Cancer stem cells (CSCs) are a subpopulation of chemoresistant cells that play a critical role in disease recurrence following chemotherapy. It has been reported that microRNA-133b (miR-133b) acts as a tumor suppressor in colorectal cancer (CRC). However, whether miR-133b is associated with CRC stemness and chemoresistance is not clear. In this study, we report that miR-133b is downregulated in colorectal spheroids, which are enriched with CSCs and display stem cell-like characteristics, including upreulation of CSCs surface markers and elevated chemoresistance. Additionally, miR-133b overexpression reduces CRC stemness and overrides chemoresistance to 5-Fluorouracil (5-FU) and oxaliplatin (OXP), indicating a negative role of miR-133b in regulating CRC stemness and chemoresistance. Moreover, miR-133b directly targets and suppresses the expression of disruptor of telomeric silencing 1-like (DOT1L), an exclusive H3K79 methyltransferase. Furthermore, miR-133b overexpression suppresses DOT1L-mediated H3K79me2 modification of stem cell genes, which is consistent with their downregulated transcription. More importantly, DOT1L restoration abrogates the suppressive effects of miR-133b on CRC stemness and chemoresistance, hence demonstrating that miR-133b regulates CRC stemness and chemoresistance through targeting DOT1L. Overall, these results imply that miR-133b might represent a novel therapeutic target in interfering CRC stemness and chemoresistance.

miR-627-3p inhibits osteosarcoma cell proliferation and metastasis by targeting PTN

Dysregulation of microRNA (miRNA) has been observed in several types of tumors, including osteosarcoma. Biochip analysis was used to identify miRNAs differentially expressed in osteosarcoma tissues. The targeting sites of miR-627-3p were analyzed using miRDB software and fluorescein reporter gene. MTT and Transwell assays were used to analyze the effects of miR-627-3p on the growth and migration of osteosarcoma cells. Western blotting and real-time PCR were used to detect the effects of miR-627-3p on related proteins. In vivo experiments were conducted to verify the effect of miR-627-3p on osteosarcoma. We focused on miR-627-3p because it was the most significantly downregulated miRNA in our screening study. Through luciferase reporter assays, western blotting and real-time PCR we found that miR-627-3p directly targets PTN, and that expression levels of miR-627-3p and PTN are negatively correlated in osteosarcoma cells. Downregulation of miR-627-3p promoted osteosarcoma cell proliferation and metastasis, while its overexpression had the opposite effect. By targeting PTN, miR-627-3p also suppressed expression of Cyclin D1 and MMP2. MiR-627-3p inhibited osteosarcoma metastasis in vivo. Thus, miR-627-3p may be a useful therapeutic target for the treatment osteosarcoma or prevention of metastasis.

MicroRNA-150-5p and SRC kinase signaling inhibitor 1 involvement in the pathological development of gastric cancer

The current study aimed to assess the regulatory mechanism of microRNA-150-5p (miR-150-5p) in the pathogenesis of gastric cancer. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was performed to verify the expression of miR-150-5p in gastric cancer tissues and cell lines, which was revealed to be highly expressed in each. In addition, the expression of miR-150-5p was associated with advanced gastric cancer and lymph node metastasis. The current study then hypothesized that SRC kinase signaling inhibitor 1 (SRCIN1) was the target gene of miR-150-5p, a theory that was confirmed via a dual luciferase reporter gene assay. RT-qPCR and western blotting were then performed to verify the expression of SRCIN1 in gastric cancer tissues and cell lines. The results demonstrated that SRCIN1 was lowly expressed in gastric cancer tissues and cells. To assess the effect of miR-150-5p on gastric cancer cells, experiments were conducted with BGC-823 cells transfected with a miR-150-5p inhibitor or a miR-150-5p inhibitor+SRCIN1-small interfering (si)RNA respectively. A cell counting kit-8 assay and flow cytometry were also used to assess cell viability and apoptosis, respectively. Western blotting and RT-qPCR were further used to measure the expression of specific markers of epithelial mesenchymal transition (EMT), including epithelial cell markers (E-cadherin and zona occluding-1) and interstitial cell markers (vimentin, N-cadherin and β-catenin). The results revealed that the miR-150-5p inhibitor attenuated cell viability, induced apoptosis, decreased the expression of interstitial cell markers and increased epithelial cell marker expression. However, all effects of the miR-150-5p inhibitor were reversed following SRCIN1-siRNA treatment. In summary, the current study indicated that the miR-150-5p inhibitor attenuated cell viability, induced apoptosis and inhibited gastric cancer cell EMT by targeting SRCIN1.

Downregulation of microRNA-425-5p suppresses cervical cancer tumorigenesis by targeting AIFM1

Although microRNA-425-5p (miR-425-5p) has been previously revealed to be upregulated in cervical cancer, the cellular function of miR-425-5p in cervical cancer remains unknown. The aim of the current study was to investigate the cellular function of miR-425-5p and its underlying mechanism in cervical cancer. Reverse transcription-quantitative polymerase chain reaction was used to measure miR-425-5p expression in several cervical cancer cell lines. TargetScan bioinformatics analysis was used to predict apoptosis-inducing factor mitochondria-associated 1 (AIFM1) as a novel target of miR-425-5p, and this was verified by dual-luciferase reporter assay. Furthermore, cell transfections were used to investigate the role of miR-425-5p in cervical cancer. The effect of miR-425-5p on cell viability and apoptosis in HeLa cells was detected by MTT assay and flow cytometry, respectively. The present study demonstrated that miR-425-5p was significantly upregulated in cervical cancer cell lines. In addition, AIFM1 was identified as a direct target of miR-425-5p and negatively regulated by miR-425-5p. Downregulation of miR-425-5p inhibited HeLa cell viability and induced cell apoptosis. Furthermore, downregulation of miR-425-5p significantly increased the protein and mRNA expression levels of cytochrome c, caspase-3, caspase-9 and DNA damage regulated autophagy modulator 1. The effects of miR-425-5p inhibition on HeLa cell viability and apoptosis were significantly reversed by AIFM1 knockdown. In conclusion, the present study demonstrated that miR-425-5p was upregulated in cervical cancer, and downregulation of miR-425-5p inhibited cervical cancer cell growth by targeting AIFM1.

Circulating microRNA-133, microRNA-17 and microRNA-25 in serum and its potential diagnostic value in gastric cancer

Gastric cancer is one of the most common malignancies in the world and is considered as the most lethal gastrointestinal cancer. microRNAs (miRNAs) can be very important in detecting a disease at an early stage. The aim of this study was to investigate the microRNA-17 (miR-17), miR-25, and miR-133b in the serum of gastric cancer subjects. Serum samples were obtained from 120 gastric cancers and 102 healthy subjects. We evaluated expression levels of miR-17, miR-25 and miR-133b by quantitative real-time polymerase chain reaction. Our results showed that in the patients with gastric cancer, the expression level of miR-17 and miR-25 were significantly increased compared with the control group (P < 0.5), while the expression level of miR-133b was significantly decreased in patient groups compared with control cases (P < 0.5). It seems that expression of miRNAs in Iranian patients with gastric cancer is similar to other patients in other populations. These findings suggested that miR-17, miR-25 and miR-133b could be introduced as potential diagnostic candidates for the detection in gastric cancer patients in the early stage.

MicroRNA-206 Reduces Osteosarcoma Cell Malignancy In Vitro by Targeting the PAX3-MET Axis

PURPOSE

This study was undertaken to explore how miR-206 represses osteosarcoma (OS) development.

MATERIALS AND METHODS

Expression levels of miR-206, PAX3, and MET mRNA were explored in paired OS and adjacent tissue specimens. A patient-derived OS cell line was established. miR-206 overexpression and knockdown were achieved by lentiviral transduction. PAX3 and MET overexpression were achieved by plasmid transfection. Treatment with hepatocyte growth factor (HGF) was utilized to activate c-Met receptor. Associations between miR-206 and PAX3 or MET mRNA in OS cells were verified by AGO2-RNA immunoprecipitation assay and miRNA pulldown assay. OS cell malignancy was evaluated in vitro by cell proliferation, metastasis, and apoptosis assays. PAX3 and MET gene expression in OS cells was assayed by RT-qPCR and Western blot. Activation of PI3K-AKT and MAPK-ERK in OS cells were assayed by evaluating Akt1 Ser473 phosphorylation and total threonine phosphorylation of Erk1/2, respectively.

RESULTS

Expression levels of miR-206 were significantly decreased in OS tissue specimens, compared to adjacent counterparts, and were inversely correlated with expression of PAX3 and MET mRNA. miR-206 directly interacted with PAX3 and MET mRNA in OS cells. miR-206 overexpression significantly reduced PAX3 and MET gene expression in OS cells in vitro, resulting in significant decreases in Akt1 and Erk1/2 activation, cell proliferation, and metastasis, as well as increases in cell apoptosis, while miR-206 knockdown showed the opposite effects. The effects of miR-206 overexpression on OS cells were reversed by PAX3 or MET overexpression, but only partially attenuated by HGF treatment.

CONCLUSION

miR-206 reduces OS cell malignancy in vitro by targeting PAX3 and MET gene expression.

MicroRNA-708-5p affects proliferation and invasion of osteosarcoma cells by targeting URGCP

Osteosarcoma is an aggressive cancer of the skeletal system which remains a challenge for the current therapeutic strategies due to unclear etiology and molecular mechanisms of pathogenesis. The current study aimed to determine the expression levels, role and molecular mechanism of microRNA-708-5p (miR-708-5p) in the development of osteosarcoma. The expression level of miR-708-5p was detected using reverse transcription-quantitative polymerase chain reaction. miR-708-5p was overexpressed in SaOS-2 cells using miR-708-5p mimics. Cell viability, apoptosis, migration and invasion were determined using Cell Counting kit-8 assay, flow cytometry, wound healing and transwell assays, respectively. The results indicated that miR-708-5p was significantly downregulated in osteosarcoma tissues and cells, and its overexpression significantly inhibited cell viability, invasion and migration and induced apoptosis of SaOS-2 cells. Furthermore, the present results indicated that miR-708-5p directly targeted the 3'-untranslated region of up-regulator of cell proliferation (URGCP) and negatively regulated its expression in SaOS-2 cells. Taken together, the current study suggested that miR-708-5p may inhibit the growth and invasion of osteosarcoma cells via regulating the URGCP/NF-κB signaling pathway. Further research on these molecules in osteosarcoma may provide novel insights into the target therapy for this disease.

miR-133b inhibits cell proliferation, migration and invasion of esophageal squamous cell carcinoma by targeting EGFR

BACKGROUND

Esophageal squamous cell carcinoma (ESCC) is an aggressive tumor entity characterized by early metastasis and late diagnosis. MicroRNA-133b (miR-133b) has been considered as a tumor suppressor in many human cancers by regulating epidermal growth factor receptor (EGFR). However, the specific effects of miR-133b and EGFR on ESCC remain unclear.

METHODS

qRT-PCR and western blotting were applied for measuring expression of mRNA and protein. Flow cytometry was used for detecting cell cycle and apoptosis. Cell proliferation, migration and invasion were detected by colony formation and transwell assays. Luciferase reporter assay was used to confirm the interaction between miR-133b and EGFR.

RESULTS

Low expression of miR-133b and high expression of EGFR were identified in ESCC cells and tissues. Overexpression of miR-133b or knockdown of EGFR suppressed the cell proliferation, migration, and invasion of ESCC cells, and raised the percentage of G1 phase cells. The apoptosis of ESCC cells were promoted by increasing miR-133b and decreasing EGFR expression. Luciferase reporter assay confirmed EGFR as the target of miR-133b in ESCC cells. Overexpression of miR-133b significantly decreased the phosphorylation of PI3K, ERK and AKT by directly down-regulating EGFR. Higher expression of E-cadherin and CK-18 and lower expression of Vimentin and N-cadherin were observed after the transfection of miR-133b mimics or shEGFR.

CONCLUSION

Overexpression of miR-133b could suppress proliferation, migration and invasion of ESCC cells by inhibiting MAPK/ERK and PI3K/AKT signaling pathways through targeting EGFR, indicating that miR-133b might be a potential therapeutic target for the treatment of ESCC.

miRNA-133b targets FGFR1 and presents multiple tumor suppressor activities in osteosarcoma

Background

Osteosarcoma (OS) is the most common bone malignancy prevalent in children and young adults. MicroRNA-133b (miR-133b), through directly targeting the fibroblast growth factor receptor 1 (FGFR1), is increasingly recognized as a tumor suppressor in different types of cancers. However, little is known on the biological and functional significance of miR-133b/FGFR1 regulation in osteosarcoma.

Methods

The expressions of miR-133b and FGFR1 were examined by RT-qPCR and compared between 30 paired normal bone tissues and OS tissues, and also between normal osteoblasts and three OS cells lines, MG-63, U2OS, and SAOS-2. Using U2OS and MG-63 as the model system, the functional significance of miR-133b and FGFR1 was assessed on cell viability, proliferation, apoptosis, migration/invasion, and epithelial–mesenchymal transition (EMT) by overexpressing miR-133b and down-regulating FGFR1 expression, respectively. Furthermore, the signaling cascades controlled by miR-133b/FGFR1 were examined.

Results

miR-133b was significantly down-regulated while FGFR1 robustly up-regulated in OS tissues and OS cell lines, when compared to normal bone tissues and normal osteoblasts, respectively. Low miR-133b expression and high FGFR1 expression were associated with location of the malignant lesion, advanced clinical stage, and distant metastasis. FGFR1 was a direct target of miR-133b. Overexpressing miRNA-133b or knocking down FGFR1 significantly reduced the viability, proliferation, migration/invasion, and EMT, but promoted apoptosis of both MG-63 and U2OS cells. Both the Ras/MAPK and PI3K/Akt intracellular signaling cascades were inhibited in response to overexpressing miRNA-133b or knocking down FGFR1 in OS cells.

Conclusion

miR-133b, by targeting FGFR1, presents a plethora of tumor suppressor activities in OS cells. Boosting miR-133b expression or reducing FGFR1 expression may benefit OS therapy.

MicroRNA-663b promotes cell proliferation and epithelial mesenchymal transition by directly targeting SMAD7 in nasopharyngeal carcinoma

MicroRNAs (miRs) serve important roles in the development of various types of human cancer, including nasopharyngeal carcinoma (NPC). In the present study, the expression levels of miR-663b in NPC were investigated and its role and underlying mechanisms were examined. Reverse transcription-quantitative polymerase chain reaction was performed to assess miR-663b expression levels in NPC tissues and C666-1 cells. TargetScan was applied to predict the putative targets of miR-663b and the dual luciferase reporter assay was used to confirm the predictions. To investigate the role of miR-663b in NPC, the NPC C666-1 cell line was transfected with miR-663b mimics, miR-663b inhibitors or negative control. The Cell Counting kit-8 assay was performed for cell proliferation detection and western blot analysis was applied to determine the expression levels of epithelial mesenchymal transition (EMT)-associated proteins. Results indicated that when compared with the adjacent normal tissues and the normal nasopharyngeal epithelial cells, miR-663b expression levels were significantly upregulated in the NPC tissues and the NPC cells (P<0.01). Notably, SMAD7 is a target gene of miR-663b and may be inhibited by miR-663b. Results indicated that NPC cell proliferation was significantly promoted by miR-663b mimics and significantly inhibited by miR-663b inhibitors (P<0.05 and P<0.01). In addition, the results indicated that, when compared with the negative control group the expression levels of E-cadherin were significantly decreased, whereas the expression levels of N-cadherin, Vimentin and matrix metalloproteinase-9 were significantly increased in the cells of the miR-663b mimics group (P<0.05 and P<0.01). However, cells in the miR-663b inhibitors group exhibited the opposite effects. In conclusion, the results of the present study indicated that miR-663b functions as a tumor promoter in NPC via promoting NPC cell proliferation and EMT by directly targeting SMAD7.

Endogenous Control Mechanisms of FAK and PYK2 and Their Relevance to Cancer Development

Focal adhesion kinase (FAK) and its close paralogue, proline-rich tyrosine kinase 2 (PYK2), are key regulators of aggressive spreading and metastasis of cancer cells. While targeted small-molecule inhibitors of FAK and PYK2 have been found to have promising antitumor activity, their clinical long-term efficacy may be undermined by the strong capacity of cancer cells to evade anti-kinase drugs. In healthy cells, the expression and/or function of FAK and PYK2 is tightly controlled via modulation of gene expression, competing alternatively spliced forms, non-coding RNAs, and proteins that directly or indirectly affect kinase activation or protein stability. The molecular factors involved in this control are frequently deregulated in cancer cells. Here, we review the endogenous mechanisms controlling FAK and PYK2, and with particular focus on how these mechanisms could inspire or improve anticancer therapies.

MicroRNA‑663b mediates TAM resistance in breast cancer by modulating TP73 expression

Breast cancer is the second leading cause of cancer‑associated mortalities in women. Tamoxifen (TAM) is an endocrine therapy commonly used in the treatment of patients with breast cancer expressing estrogen receptor α. However, treatment often ends in failure due to the emergence of drug resistance. MicroRNAs (miRNAs), a family of small non‑coding RNAs, serve critical roles in the regulation of gene expression and cell events. To date, whether miRNA‑663b could mediate TAM resistance in breast cancer remains unknown. Therefore, the aim of the present study was to investigate the role of miRNA‑663b in TAM resistance in breast cancer. The results demonstrated that miRNA‑663b was upregulated in breast cancer with TAM resistance. Tumor protein 73 (TP73) was a direct target of miRNA‑663b, and was negatively regulated by miRNA‑663b in MCF‑7 cells. Furthermore, it was identified that downregulation of miRNA‑663b inhibited cell proliferation ability and promoted cell apoptosis, resulting in enhanced TAM sensitivity. In addition, these findings suggested that TP73 silencing may have eliminated the effects of miRNA‑663b inhibitor on breast cancer cells. In conclusion, the present study verified a novel molecular link between miRNA‑663b and TP73, and indicated that miRNA‑663b may be a critical therapeutic target in breast cancer.

miR-133b, a particular member of myomiRs, coming into playing its unique pathological role in human cancer

MicroRNAs, a family of single-stranded and non-coding RNAs, play a crucial role in regulating gene expression at posttranscriptional level, by which it can mediate various types of physiological and pathological process in normal developmental progress and human disease, including cancer. The microRNA-133b originally defined as canonical muscle-specific microRNAs considering their function to the development and health of mammalian skeletal and cardiac muscles, but new findings coming from our group and others revealed that miR-133b have frequently abnormal expression in various kinds of human cancer and its complex complicated regulatory networks affects the tumorigenicity and development of malignant tumors. Very few existing reviews on miR-133b, until now, are principally about its role in homologous cluster (miR-1, −133 and -206s), however, most of constantly emerging new researches now are focused mainly on one of them, so In this article, to highlight the unique pathological role of miR-133b playing in tumor, we conduct a review to summarize the current understanding about one of the muscle-specific microRNAs, namely miR-133b, acting in human cancer. The review focused on the following four aspects: the overview of miR-133b, the target genes of miR-133b involved in human cancer, the expression of miR-133b and regulatory mechanisms leading to abnormal expression of miR-133b.

Identification of a microRNA signature associated with survivability in cervical squamous cell carcinoma

Background

The aim of this study is to find the potential miRNA expression signature capable of predicting survival time for cervical squamous cell carcinoma (CSCC) patients.

Methods

The expression of 332 miRNAs was measured in 131 (Training cohort) and 130 (Validation cohort) patients with CSCC in the Cancer Genome Atlas (TCGA) data portal. The miRNA expression signature was identified by Cox Proportion Hazard regression model to the Training data set, and subsequently validated in an independent Validation set. Kaplan-Meier curves and the receiver operating characteristic analyses of 5 years were used to access the overall survival of miRNA signature. MiRNA signature-gene target analysis was performed, followed by the construction of the regulatory network. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analysis were used to explore the function of target genes of miRNA signature.

Results

A 2-miRNA expression signature of hsa-mir-642a and hsa-mir-378c associated with survivability was identified in CSCC. Both of them had a significant diagnostic and prognostic value of patients with CSCC. A total of 345 miRNA signature-target pairs were obtained in the miRNA signature-gene target regulatory network, in which 316 genes were targets of has-mir-378c and has-mir-642a. Functional analysis of target genes showed that MAPK signaling pathway, VEGF signaling pathway and endocytosis were the significantly enriched signal pathways that covered most genes.

Conclusions

The 2-miRNA signature adds to the prognostic value of CSCC. In-depth interrogation of the 2-miRNAs will provide important biological insights that finding and developing novel molecularly prediction to improve prognosis for CSCC patients.

MicroRNA-133b inhibits cell proliferation and promotes apoptosis by targeting cullin 4B in esophageal squamous cell carcinoma

microRNAs (miRs) serve a role as modulators during carcinogenesis. It has been demonstrated that the expression of miR-133b is decreased in a variety of tumor tissues and cell lines and serves a suppressive role in the proliferation and apoptosis of different types of tumor cells. However, its effect on esophageal squamous cell carcinoma (ESCC) cells remains unclear. In the current study, the expression of mature miR-133b was measured using reverse transcription-quantitative polymerase chain reaction and the results indicated that miR-133b was significantly downregulated in ESCC tissues and various ESCC cell lines. The overexpression of miR-133b significantly inhibited the proliferation and promoted the apoptosis of KYSE150 and Eca-109 cells. Furthermore, it was demonstrated that cullin 4B (CUL4B) promotes ESCC cell proliferation and inhibits apoptosis by activating the protein kinase B/glycogen synthase kinase 3β/β-catenin pathway. Taken together, these results demonstrate that miR-133b/CUL4B serves a tumor suppressive role during ESCC progression and may therefore be used as a potential target to treat patients with ESCC.

miR-223/Hsp70/JNK/JUN/miR-223 feedback loop modulates the chemoresistance of osteosarcoma to cisplatin

Osteosarcoma (OS) is a primary bone malignancy with a five-year survival rate of 60%; the chemoresistance of OS still remains a huge challenge. Heat shock protein 70 (Hsp70), a member of HSP family, is overexpressed in OS cell lines and involved in the resistance of OS cell lines. In addition, miRNAs have been involved in the carcinogenesis and chemoresistance of OS; of them, miR-223 has been reported to be underexpressed and serve as a tumor suppressor in OS through targeting Hsp90B1, also a member of HSP family. Herein, online tools predicted that Hsp70 might be a direct target of miR-223. In the present study, miR-223 expression was down-regulated in OS tissues and cell lines; miR-223 overexpression enhanced the cellular effects of cisplatin (CDDP) on OS cell lines. Through binding to the HSPA1A 3'UTR, miR-223 could regulate Hsp70 protein levels and downstream JNK/JUN signaling pathway, thus modulating OS cell apoptosis through Hsp70 under CDDP stress. Finally, JUN, a downstream transcription factor of JNK signaling, could bind to the promoter region of miR-223 to promote its transcription. In summary, miR-223, Hsp70 and downstream JNK/JUN formed a feedback loop to modulate the chemoresistance of OS to CDDP.

miR-133b induces chemoresistance of osteosarcoma cells to cisplatin treatment by promoting cell death, migration and invasion

As an important chemotherapeutic agent for the treatment of osteosarcoma, the effectiveness of cisplatin is considered to be due to its unique properties, which allow it to penetrate the cell membrane and form various DNA-platinum adducts, resulting in genetic alterations or DNA damage. However, chemoresistance to cisplatin remains a major challenge for its use and chemotherapeutic effects. In the present study, an isogenic model of a cisplatin resistant osteosarcoma cell line, MG63-DDP, was generated from the original MG63 cell line. The expression level of microRNA (miR)-133b in the MG63-DDP cisplatin-resistant osteosarcoma cell line was analyzed by reverse transcription-quantitative polymerase chain reaction (PCR). Cisplatin-DNA adduct formation, cell death (carboxyfluorescein succinimidyl ester/propidium iodide staining) and clonogenic survival assays (crystal violet staining) were performed, comparing various cell types. The effect of miR-133b on migration (scratch wound assay) and invasion (Transwell assay) was also evaluated. Characterization studies have previously revealed an increased level of miR-133b in MG63-DDP cells compared with normal MG63 cells. Upregulation of miR-133b was associated with the accumulation of cisplatin-DNA adducts and an increase in cisplatin-induced cell death. Furthermore, increased miR-133b expression levels enhanced the migration and invasion of MG63 cells under cisplatin stress. Concordantly, in MG63-DDP cells the neutralization of miR-133b demonstrated opposite effects, as compared with the upregulation of miR-133b. To the best of our knowledge, the present study demonstrated for the first time that cisplatin-resistant MG63 cells exhibit an increased level of miR-133b expression. The endogenous expression level of miR-133b is sufficient for inducing cisplatin resistance, which suggests that miR-133b may be a biomarker for cisplatin resistance in osteosarcoma.

MicroRNA-505 is downregulated in human osteosarcoma and regulates cell proliferation, migration and invasion

Recent studies have demonstrated that microRNAs (miRNAs/miRs) are involved in osteosarcoma tumorigenesis, progression, invasion and metastasis. For example, miR-505 plays important roles in human carcinogenesis; however, its exact function in osteosarcoma remains unclear. MicroRNA profiles of osteosarcoma and normal tissues were obtained by miRNA microarray assays, which were validated by quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR). Then, high-mobility group box 1 (HMGB1) expression was evaluated by qRT-PCR and western blot analysis. The correlation between miR-505 and HMGB1 was analyzed by Pearson correlation. In vitro, the biological functions of miR-505 were examined by wound healing, MTT and Transwell assays and western blot analysis in MG63 cells transfected with miRNA mimics or empty vector. Luciferase assay was utilized to assess whether HMGB1 is a target of miR-505. miRNA microarrays revealed 26 aberrant miRNAs in osteosarcoma tissues; miR-505 showed the most pronounced decrease (P<0.01), which was significantly associated with TNM stage and metastasis status (P<0.05). In addition, HMGB1 was highly expressed in osteosarcoma tissues (P<0.01), with a significantly negative correlation with miR-505 (r=−0.6679, P<0.001). Furthermore, miR-505 inhibited proliferation, migration and invasion abilities of MG63 cells (P<0.01). Moreover, luciferase activity of the HMGB1-3′-UTR plasmid was suppressed following miR-505 binding (P<0.01). Finally, HMGB1 overexpression partly reversed the effects of miR-505 on MG63 cells. In conclusion, miR-505 levels are decreased in osteosarcoma tissues, and reduced miR-505 expression is significantly associated with poorer clinical prognosis in patients with osteosarcomas. miR-505 inhibits osteosarcoma cell proliferation, migration and invasion by regulating HMGB1.

Circulating biomarkers in osteosarcoma: new translational tools for diagnosis and treatment

Osteosarcoma (OS) is a rare primary malignant bone tumour arising from primitive bone-forming mesenchymal cells, with high incidence in children and young adults, accounting for approximately 60% of all malignant bone tumours. Currently, long-term disease-free survival can be achieved by surgical treatment plus chemotherapy in approximately 60% of patients with localized extremity disease, and in 20-30% of patients with metastatic lung or bone disease. Diagnosis of primary lesions and recurrences is achieved by using radiological investigations and standard tissue biopsy, the latter being costly, painful and hardly repeatable for patients. Therefore, despite some recent advances, novel biomarkers for OS diagnosis, prediction of response to therapy, disease progression and chemoresistance, are urgently needed. Biological fluids such as blood represent a rich source of non-invasive cancer biomarkers, which allow to understand what is really happening inside the tumour, either at diagnosis or during disease progression. In this regard, liquid biopsy potentially represents an alternative and non-invasive method to detect tumour onset, progression and response to therapy. In this review, we will summarize the state of the art in this novel area, illustrating recent studies on OS. Although the data reported in literature seem preliminary, liquid biopsy represents a promising tool with the potential to be rapidly translated in the clinical practice.

Procaine Inhibits Proliferation and Migration and Promotes Cell Apoptosis in Osteosarcoma Cells by Upregulation of MicroRNA-133b

Procaine (PCA) is a conventional chemotherapeutic agent for osteosarcoma. Recent studies have proposed that the growth-inhibitory effect of PCA is through regulation of microRNAs (miRNAs). miR-133b has been proven to be a tumor suppressor in osteosarcoma, but whether it is involved in the antitumor effects of PCA on osteosarcoma has not been investigated. In this study, we aimed to explore the effects of PCA on osteosarcoma MG63 cells by regulation of miR-133b, as well as its underlying mechanisms. MG63 cells were treated with different concentrations of PCA, and cell viability, apoptosis, and miR-133b expression were then detected by MTT, flow cytometry, and qRT-PCR, respectively. Cells were then transfected with the miR-133b inhibitor and treated with 2 μM PCA. Thereafter, cell viability, migration, and apoptosis were detected. Analysis of signaling pathways was detected by Western blot. Our results showed that PCA significantly inhibited cell viability and promoted apoptosis and the expression level of miR-133b in a dose-dependent manner (p < 0.05 or p < 0.01). Moreover, we observed that PCA + miR-133b inhibitor dramatically reversed the effects of PCA on cell viability, apoptosis, and migration (p < 0.05 or p < 0.01). In addition, PCA significantly decreased the levels of p/t-AKT (p308 or p473), p/t-ERK, and p/t-S6, whereas PCA + miR-133b inhibitor rescued these effects. Our results suggest that PCA inhibits proliferation and migration but promotes apoptosis in osteosarcoma cells by upregulation of miR-133b. These effects may be achieved by inactivation of the AKT/ERK pathways.

Downregulation of lizard immuno-genes in the regenerating tail and myogenes in the scarring limb suggests that tail regeneration occurs in an immuno-privileged organ

Amputated tails of lizards regenerate while limbs form scars which histological structure is very different from the original organs. Lizards provide useful information for regenerative medicine and some hypotheses on the loss of regeneration in terrestrial vertebrates. Analysis of tail and limb transcriptomes shows strong downregulation in the tail blastema for immunoglobulins and surface B and T receptors, cell function, and metabolism. In contrast, in the limb blastema genes for myogenesis, muscle and cell function, and extracellular matrix deposition but not immunity are variably downregulated. The upregulated genes show that the regenerating tail is an embryonic organ driven by the Wnt pathway and non-coding RNAs. The strong inflammation following amputation, the non-activation of the Wnt pathway, and the upregulation of inflammatory genes with no downregulation of immune genes indicate that the amputated limb does not activate an embryonic program. Intense inflammation in limbs influences in particular the activity of genes coding for muscle proteins, cell functions, and stimulates the deposition of dense extracellular matrix proteins resulting in scarring limb outgrowths devoid of muscles. The present study complements that on upregulated genes, and indicates that the regenerating tail requires immune suppression to maintain this embryonic organ connected to the rest of the tail without be rejected or turned into a scar. It is hypothesized that the evolution of the adaptive immune system determined scarring instead of organ regeneration in terrestrial vertebrates and that lizards evolved the process of tail regeneration through a mechanism of immuno-evasion.

miR-133b acts as a tumor suppressor and negatively regulates ATP citrate lyase via PPARγ in gastric cancer

MicroRNAs (miRNAs/miRs) are a class of small noncoding RNAs that negatively regulate protein expression by binding to protein-coding mRNAs and suppressing translation. Accumulating evidence suggests that miRNAs are involved in the development and progression of cancer by regulating cancer metabolism. Meanwhile, the cytosolic enzyme ATP citrate lyase (ACLY) is a promising target in the prevention and treatment of cancer. In the present study we revealed by western blot analysis and reverse transcription‑quantitative PCR that miR-133b was downregulated in human gastric cancer (GC) tissues and cell lines, while ACLY was upregulated. The overexpression of miR-133b could decrease the proliferation and invasion of MKN-74 cells by inhibiting the expression and activation of ACLY. Furthermore, the nuclear distribution of peroxisome proliferator-activated receptor-γ (PPARγ) in GC tissues and cell lines was markedly decreased, and overexpression of miR-133b could increase the levels of nuclear PPARγ in MKN-74 cells. Additionally, miR-133b decreased the transcriptional activity of ACLY in a PPARγ-dependent manner, as determined by a dual-luciferase reporter assay. These results indicate that miR-133b targets ACLY and inhibits GC cell proliferation by regulating the expression of PPARγ, suggesting that miR-133b may serve as a tumor-suppressive target in GC therapy.

Forkhead box C1 is targeted by microRNA-133b and promotes cell proliferation and migration in osteosarcoma

Forkhead box C1 (FOXC1) has been demonstrated to act as an oncogene in a number of malignant tumors, though its underlying mechanism of action in osteosarcoma (OS) remains unknown. The present study evaluated the expression and regulatory role of FOXC1 in OS. Reverse transcription-quantitative polymerase chain reaction and western blot data indicated that FOXC1 was significantly upregulated in OS tissues and cell lines when compared with adjacent non-tumor tissues (P<0.001) and normal human osteoblast cells (P<0.01), respectively. Moreover, levels of FOXC1 expression were significantly higher in OS at advanced clinical stage (III–IV) when compared with that at low clinical stage (I–II; P<0.001). Knockdown of FOXC1 expression caused a significant decrease in the proliferation and migration of OS U2OS cells (P<0.01), while overexpression of FOXC1 significantly promoted U2OS cell proliferation and migration (P<0.01), relative to control U2OS cells. Furthermore, FOXC1 was identified as a direct target of microRNA (miR)-133b, a reported tumor-suppressive miR in OS. The protein expression of FOXC1 was negatively regulated by miR-133b in U2OS cells (P<0.01), and miR-133b expression was inversely correlated with FOXC1 expression in OS. In conclusion, the present study demonstrated that FOXC1, targeted by miR-133b, may promote cell proliferation and migration in OS. Thus, FOXC1 may be a potential therapeutic target in the treatment of OS.

lnc133b, a novel, long non-coding RNA, regulates bovine skeletal muscle satellite cell proliferation and differentiation by mediating miR-133b

The proliferation and differentiation of skeletal muscle satellite cells is regulated by multiple regulatory factors including non-coding RNAs. It has been reported that miR-133b regulates myogenesis. In this study, we detected a novel lncRNA, lnc133b, which is completely complemented by mature miR-133b, indicating that lnc133b may regulate the expression of miR-133b by "sponge" miR-133b. A luciferase report assay confirmed that lnc133b interacts with miR-133b in regions complemented by miR-133b. We successfully constructed lnc133b gain/loss-of-function cell models by infecting LV-1nc133b and transfecting si-lnc133b into satellite cells. Results of quantitative real-time polymerase chain reaction (qRT-PCR) and 5-ethynyl-2'-deoxyuridine (EdU) assays showed that overexpression or inhibition of lnc133b could promote the proliferation or inhibition of satellite cell differentiation. The qRT-PCR results also showed that lnc133b negatively regulates miR-133b expression and a Western blot assay showed that lnc133b positively regulates IGF1R expression, indicating that the lnc133b/miR-133b/IGF1R axis is a potential pathway for promoting satellite cell proliferation and repressing their differentiation through the ceRNA mechanism. Building on the findings of previous reports, we constructed the lnc133b/miR-133b/FGFR1 & PP2AC pathway to improve the lnc133b regulation network regulating the proliferation and differentiation of satellite cells. The current study provides a new perspective for understanding the mechanism regulating satellite cell proliferation and differentiation through the interaction of miR-133b and lnc133b.

Downregulation of Ubiquitin-Specific Protease 22 Inhibits Proliferation, Invasion, and Epithelial-Mesenchymal Transition in Osteosarcoma Cells

Ubiquitin-specific protease 22 (USP22), a novel deubiquitinating enzyme, belongs to an extended family of proteins that have ubiquitin hydrolase activity. Recently, USP22 has attracted widespread attention because of its implication in carcinogenesis. However, there have been no studies, to our knowledge, investigating the expression of USP22 in osteosarcoma (OS) and its association with OS progression. In this study, we explored the role of USP22 in OS. We demonstrated that USP22 was highly expressed in OS tissue and cell lines. Downregulation of USP22 inhibited OS cell proliferation, invasion, and epithelial-mesenchymal transition (EMT) in vitro. In addition, downregulation of USP22 suppressed OS tumor growth and metastasis in vivo. We also found that the PI3K/Akt signaling pathway was involved in the tumor-promoting effect of USP22 on OS progression. Taken together, we suggest USP22 as a novel therapeutic target for OS.

MicroRNA-133b Inhibits Proliferation, Cellular Migration, and Invasion via Targeting LASP1 in Hepatocarcinoma Cells

MicroRNAs (miRs), a class of small noncoding RNAs, are key gene regulators through inducing translational repression or degradation of their target genes. However, the regulatory mechanism of miR-133b underlying hepatocellular carcinoma (HCC) growth and metastasis remains largely unclear. Here we found that miR-133b was significantly downregulated in HCC tissues and cell lines. Moreover, low miR-133b levels were significantly associated with the malignant progression of HCC. LASP1, upregulated in HCC tissues and cell lines, was then identified as a novel target of miR-133b in HCC HepG2 and Hep3B cells. Moreover, the increased expression of LASP1 was associated with HCC progression. An in vitro study showed that overexpression of miR-133b inhibited the proliferation, migration, and invasion of HepG2 and Hep3B cells. Similarly, knockdown of LASP1 reduced HepG2 and Hep3B cell proliferation, migration, and invasion. Furthermore, overexpression of LASP1 attenuated the suppressive effect of miR-133b on the malignant phenotypes of HepG2 and Hep3B cells, suggesting that miR-133b may inhibit HCC growth and metastasis via targeting LASP1. In addition, overexpression of miR-133b inhibits tumor growth of HepG2 and Hep3B cells in vivo. Therefore, the miR-133b/LASP1 axis may become a potential target for the treatment of HCC.

Differentially expressed miRNAs in oxygen‑induced retinopathy newborn mouse models

The present study aimed to identify microRNAs (miRNAs) involved in regulating retinal neovascularization and retinopathy of prematurity (ROP). A total of 80 healthy C57BL/6 neonatal mice were randomly divided into the oxygen-induced retinopathy (OIR) group (n=40), in which 7-day-old mice were maintained in 75% oxygen conditions for 5 days, or the control group (n=40). Following collection of retinal tissue, retinal angiography and hematoxylin and eosin (H&E) staining were performed. Total RNA was also extracted from retinal tissue, and miRNA microarrays and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were performed to identify differentially expressed miRNAs in the two groups. Retinal angiography and H&E staining revealed damage to retinas in the OIR group. Compared with the control group, 67 miRNAs were differentially expressed in the OIR group, of which 34 were upregulated and 33 were downregulated. Of these differentially expressed miRNAs, 32 exhibited a fold change ≥2, of which 21 were upregulated and 11 were downregulated. The results of RT-qPCR for miR-130a-3p and miR-5107-5p were in accordance with those of the miRNA microarray. The newly identified miRNAs may be important in the development of ROP, and may provide a basis for future research into the mechanisms of ROP.