miR-155 inhibitor reduces the proliferation and migration in osteosarcoma MG-63 cells

The fate and function of non-coding RNAs during necroptosis

Necroptosis is a novel form of cell death which is activated when apoptotic cell death signals are disrupted. Accumulating body of observations suggests that noncoding RNAs, which are the lately discovered mystery of the human genome, are significantly associated with necroptotic signaling circuitry. The fate and function of miRNAs have been well documented in human disease, especially cancer. Recently, lncRNAs have gained much attention due to their diverse regulatory functions. Although available studies are currently based on bioinformatic analysis, predicted interactions desires further attention, as these hold significant promise and should not be overlooked. In the light of these, here we comprehensively review and discuss noncoding RNA molecules that play significant roles during execution of necroptotic cell death.

MicroRNA-Mediated Regulation of Histone-Modifying Enzymes in Cancer: Mechanisms and Therapeutic Implications

In the past decade, significant advances in molecular research have provided a deeper understanding of the intricate regulatory mechanisms involved in carcinogenesis. MicroRNAs, short non-coding RNA sequences, exert substantial influence on gene expression by repressing translation or inducing mRNA degradation. In the context of cancer, miRNA dysregulation is prevalent and closely associated with various stages of carcinogenesis, including initiation, progression, and metastasis. One crucial aspect of the cancer phenotype is the activity of histone-modifying enzymes that govern chromatin accessibility for transcription factors, thus impacting gene expression. Recent studies have revealed that miRNAs play a significant role in modulating these histone-modifying enzymes, leading to significant implications for genes related to proliferation, differentiation, and apoptosis in cancer cells. This article provides an overview of current research on the mechanisms by which miRNAs regulate the activity of histone-modifying enzymes in the context of cancer. Both direct and indirect mechanisms through which miRNAs influence enzyme expression are discussed. Additionally, potential therapeutic implications arising from miRNA manipulation to selectively impact histone-modifying enzyme activity are presented. The insights from this analysis hold significant therapeutic promise, suggesting the utility of miRNAs as tools for the precise regulation of chromatin-related processes and gene expression. A contemporary focus on molecular regulatory mechanisms opens therapeutic pathways that can effectively influence the control of tumor cell growth and dissemination.

MicroRNA-155 and cancer metastasis: Regulation of invasion, migration, and epithelial-to-mesenchymal transition

Among the leading causes of death globally has been cancer. Nearly 90% of all cancer-related fatalities are attributed to metastasis, which is the growing of additional malignant growths out of the original cancer origin. Therefore, a significant clinical need for a deeper comprehension of metastasis exists. Beginning investigations are being made on the function of microRNAs (miRNAs) in the metastatic process. Tiny non-coding RNAs called miRNAs have a crucial part in controlling the spread of cancer. Some miRNAs regulate migration, invasion, colonization, cancer stem cells' properties, the epithelial-mesenchymal transition (EMT), and the microenvironment, among other processes, to either promote or prevent metastasis. One of the most well-conserved and versatile miRNAs, miR-155 is primarily distinguished by overexpression in a variety of illnesses, including malignant tumors. It has been discovered that altered miR-155 expression is connected to a number of physiological and pathological processes, including metastasis. As a result, miR-155-mediated signaling pathways were identified as possible cancer molecular therapy targets. The current research on miR-155, which is important in controlling cancer cells' invasion, and metastasis as well as migration, will be summarized in the current work. The crucial significance of the lncRNA/circRNA-miR-155-mRNA network as a crucial regulator of carcinogenesis and a player in the regulation of signaling pathways or related genes implicated in cancer metastasis will be covered in the final section. These might provide light on the creation of fresh treatment plans for controlling cancer metastasis.

Targeting miRNAs and Other Non-Coding RNAs as a Therapeutic Approach: An Update

Since the discovery of the first microRNAs (miRNAs, miRs), the understanding of miRNA biology has expanded substantially. miRNAs are involved and described as master regulators of the major hallmarks of cancer, including cell differentiation, proliferation, survival, the cell cycle, invasion, and metastasis. Experimental data indicate that cancer phenotypes can be modified by targeting miRNA expression, and because miRNAs act as tumor suppressors or oncogenes (oncomiRs), they have emerged as attractive tools and, more importantly, as a new class of targets for drug development in cancer therapeutics. With the use of miRNA mimics or molecules targeting miRNAs (i.e., small-molecule inhibitors such as anti-miRS), these therapeutics have shown promise in preclinical settings. Some miRNA-targeted therapeutics have been extended to clinical development, such as the mimic of miRNA-34 for treating cancer. Here, we discuss insights into the role of miRNAs and other non-coding RNAs in tumorigenesis and resistance and summarize some recent successful systemic delivery approaches and recent developments in miRNAs as targets for anticancer drug development. Furthermore, we provide a comprehensive overview of mimics and inhibitors that are in clinical trials and finally a list of clinical trials based on miRNAs.

lncRNA HOXA11-AS Promotes Proliferation and Migration via Sponging miR-155 in Hypopharyngeal Squamous Cell Carcinoma

Hypopharyngeal squamous cell carcinoma (HSCC) remains one of the most lethal malignancies in the head and neck. Long noncoding RNA (lncRNA) HOXA11-AS is proven to function as an oncogene and a therapeutic target in various tumors. Our previous study and others have demonstrated that HOXA11-AS is one of the most upregulated lncRNAs in HSCC. However, the role of HOXA11-AS in HSCC has not yet been identified. The current study demonstrated that the expression of HOXA11-AS was significantly upregulated in HSCC tumors and was positively associated with lymph node metastasis. Moreover, functional experiments revealed that HOXA11-AS knockdown suppressed the proliferation and migration potential in FaDu cells. Furthermore, luciferase reporter gene assay combined with cellular functional experiments demonstrated that HOXA11-AS functioned as a molecular sponge for miR-155, and inhibition of miR-155 attenuated the suppressive effect of HOXA11-AS knockdown on the aggressive phenotype in HSCC. This study identifies a tumor-promoting role of HOXA11-AS in HSCC and suggests HOXA11-AS might be a potential diagnostic and therapeutic target for HSCC.

miRNA signatures in childhood sarcomas and their clinical implications

Progresses in multimodal treatments have significantly improved the outcomes for childhood cancer. Nonetheless, for about one-third of patients with Ewing sarcoma, rhabdomyosarcoma, or osteosarcoma steady remission has remained intangible. Thus, new biomarkers to improve early diagnosis and the development of precision-targeted medicine remain imperative. Over the last decade, remarkable progress has been made in the basic understanding of miRNAs function and in interpreting the contribution of their dysregulation to cancer development and progression. On this basis, this review focuses on what has been learned about the pivotal roles of miRNAs in the regulation of key genes implicated in childhood sarcomas.

miR-155 in cancer drug resistance and as target for miRNA-based therapeutics

Small non-coding microRNAs (miRNAs) are instrumental in physiological processes, such as proliferation, cell cycle, apoptosis, and differentiation, processes which are often disrupted in diseases like cancer. miR-155 is one of the best conserved and multifunctional miRNAs, which is mainly characterized by overexpression in multiple diseases including malignant tumors. Altered expression of miR-155 is found to be associated with various physiological and pathological processes, including hematopoietic lineage differentiation, immune response, inflammation, and tumorigenesis. Furthermore, miR-155 drives therapy resistance mechanisms in various tumor types. Therefore, miR-155-mediated signaling pathways became a potential target for the molecular treatment of cancer. In this review, we summarize the current findings of miR-155 in hematopoietic lineage differentiation, the immune response, inflammation, and cancer therapy resistance. Furthermore, we discuss the potential of miR-155-based therapeutic approaches for the treatment of cancer.

MicroRNA-150 functions as an antioncogenic regulator in osteosarcoma

Numerous studies have demonstrated that microRNAs (miRs) are involved in several physiological and pathological processes, and participate in cancer initiation and progression. The abnormal expression of miR-150 has been reported in numerous types of human cancer. However, at present there are no studies of miR-150 in osteosarcoma (OS). Reverse transcription-quantitative polymerase chain reaction was performed to measure miR-150 expression levels in OS tissues and cell lines. Subsequent to transfection with miR-150 mimics or zinc finger E-box binding homeobox 1 (ZEB1) small interfering RNA, an MTT assay, Transwell migration and invasion assays, western blotting and a Dual-Luciferase reporter assay were performed in human OS cell lines. The present study revealed that miR-150 was downregulated in OS tissues and cell lines. In addition, the expression levels of miR-150 were correlated with the clinical stage and degree of distant metastasis of patients with OS. In addition, ZEB1 was identified as a direct target of miR-150 in vitro. In conclusion, miR-150 targeted ZEB1 to function as an antioncogenic regulator in OS. These findings elucidated a novel underlying mechanism for the pathogenic process in OS carcinogenesis and progression, and may provide novel targeted therapeutic regimens for patients with OS.

MiR-155 up-regulated by TGF-β promotes epithelial-mesenchymal transition, invasion and metastasis of human hepatocellular carcinoma cells in vitro

It has previously been reported that microRNA (miR)-155 is linked to the recurrence and prognosis of hepatocellular carcinoma (HCC) following liver transplantation. However, the role of miR-155 in the invasion and metastasis of HCC cells remains largely unclear. The aim of this study was to investigate the expression of miR-155 in HCC cells and its role in the invasion and migration of HCC cells in vitro. We found that the level of expression of miR-155 in HCC tissues and cells was significantly increased compared with non-tumorous adjacent tissues. Further study revealed that recombinant human transforming growth factor-β (TGF-β1) up-regulated the expression of miR-155 in HCC cells in vitro. Further, the overexpression of miR-155 in HCC cell line Huh-7 led to increased levels of cell invasion and migration compared with untreated control Huh-7 cells. MiR-155-overexpressed Huh-7 cells also exhibited altered levels of expression of certain cellular adhesion molecules related to epithelial-mesenchymal transition (EMT), including low levels of CDH1 and higher levels of FN1, SNAI1 and ZEB1, compared with control Huh-7 cells. Moreover, it was found that the overexpression of miR-155 and of TGF-β1 protein decreased the expression of E-Cadherin and increased the expression of Vimentin in Huh-7 cells. These results indicate that an increased level of miR-155 in HCC cells, possibly due to stimulation by TGF-β1, accelerates the process of EMT, promotes cellular invasion and migration in vitro, and thereby further promotes the progression of HCC.

miRNAs Related to Skeletal Diseases

miRNAs as non-coding, short, double-stranded RNA segments are important for cellular biological functions, such as proliferation, differentiation, and apoptosis. miRNAs mainly contribute to the inhibition of important protein translations through their cleavage or direct repression of target messenger RNAs expressions. In the last decade, miRNAs got in the focus of interest with new publications on miRNAs in the context of different diseases. For many types of cancer or myocardial damage, typical signatures of local or systemically circulating miRNAs have already been described. However, little is known about miRNA expressions and their molecular effect in skeletal diseases. An overview of published studies reporting miRNAs detection linked with skeletal diseases was conducted. All regulated miRNAs were summarized and their molecular interactions were illustrated. This review summarizes the involvement and interaction of miRNAs in different skeletal diseases. Thereby, 59 miRNAs were described to be deregulated in tissue, cells, or in the circulation of osteoarthritis (OA), 23 miRNAs deregulated in osteoporosis, and 107 miRNAs deregulated in osteosarcoma (OS). The molecular influences of miRNAs regarding OA, osteoporosis, and OS were illustrated. Specific miRNA signatures for skeletal diseases are described in the literature. Some overlapped, but also unique ones for each disease exist. These miRNAs may present useful targets for the development of new therapeutic approaches and are candidates for diagnostic evaluations.

MicroRNA-224 promotes the sensitivity of osteosarcoma cells to cisplatin by targeting Rac1

Osteosarcoma is the most common primary bone tumour in children and adolescents. Accumulating evidence has shown that microRNAs (miRNAs) participate in the development of almost all types of cancer. Here, we investigated the role of miR‐224 in the development and progression of osteosarcoma. We demonstrated that miR‐224 was down‐regulated in osteosarcoma cell lines and tissues. Lower miR‐224 levels were correlated with shorter survivalin osteosarcoma patients. Furthermore, overexpression of miR‐224 suppressed osteosarcoma cell proliferation, migration and invasion and contributed to the increased sensitivity of MG‐63 cells to cisplatin. We identified Rac1 as a direct target gene of miR‐224 in osteosarcoma. Rac1 expression was up‐regulated in the osteosarcoma cell lines and tissues, and there was an inverse correlation between Rac1 and miR‐224 expression in osteosarcoma tissues. Furthermore, rescuing Rac1 expression decreased the sensitivity of miR‐224‐overexpressing MG‐63 cells to cisplatin. We also demonstrated that ectopic expression of Rac1 promoted the proliferation, migration and invasion of miR‐224‐overexpressing MG‐63 cells. These data suggest that miR‐224 plays a tumour suppressor role in the development of osteosarcoma and is related to the sensitivity of osteosarcoma to cisplatin.

Increased miR-155-5p and reduced miR-148a-3p contribute to the suppression of osteosarcoma cell death

Osteosarcoma (OS) is the most common cancer of bone and the 5th leading cause of cancer-related death in young adults. Currently, 5-year survival rates have plateaued at ~70% for patients with localized disease. Those with disseminated disease have an ~20% 5-year survival. An improved understanding of the molecular genetics of OS may yield new approaches to improve outcomes for OS patients. To this end, we applied murine models that replicate human OS to identify and understand dysregulated microRNAs (miRNAs) in OS. miRNA expression patterns were profiled in murine primary osteoblasts, osteoblast cultures and primary OS cell cultures (from primary and paired metastatic locations) isolated from two genetically engineered murine models of OS. The differentially expressed miRNA were further assessed by a cross-species comparison with human osteoblasts and OS cultures. We identified miR-155-5p and miR-148a-3p as deregulated in OS. miR-155-5p suppression or miR-148a-3p overexpression potently reduced proliferation and induced apoptosis in OS cells, yet strikingly, did not impact normal osteoblasts. To define how these miRNAs regulated OS cell fate, we used an integrated computational approach to identify putative candidate targets and then correlated these with the cell biological impact. Although we could not resolve the mechanism through which miR-148a-3p impacts OS, we identified that miR-155-5p overexpression suppressed its target Ripk1 (receptor (TNFRSF)-interacting serine-threonine kinase 1) expression, and miR-155-5p inhibition elevated Ripk1 levels. Ripk1 is directly involved in apoptosis/necroptosis. In OS cells, small interfering RNA against Ripk1 prevented cell death induced by the sequestration of miR-155-5p. Collectively, we show that miR-148a-3p and miR-155-5p are species-conserved deregulated miRNA in OS. Modulation of these miRNAs was specifically toxic to tumor cells but not normal osteoblasts, raising the possibility that these may be tractable targets for miRNA-based therapies for OS.

miR-9 Modulates Osteosarcoma Cell Growth by Targeting the GCIP Tumor Suppressor

Osteosarcoma is the most common primary bone tumor in humans, especially in childhood. However, the genetic etiology for its pathogenesis remains elusive. It is known that microRNAs (miRNAs) are involved in the development of tumor progression. Here we show that microRNA-9 (miR-9) is a potential oncogene upregulated in osteosarcoma cells. Knockdown of miR-9 in osteosarcoma resulted in suppressed colony formation and cell proliferation. Further study identified GCIP, a Grap2 and cyclin D interacting protein, as a direct target of miR- 9. In addition, GCIP overexpression activated retinoblastoma 1 (Rb) and suppressed E2F transcriptional target expression in osteosarcoma cells. Moreover, GCIP depletion reversed miR-9 knockdown induced colony formation and cell proliferation suppression. In sum, these results highlight the importance of miR-9 as an oncogene in regulating the proliferation of osteosarcoma by directly targeting GCIP and may provide new insights into the pathogenesis of osteosarcoma.

Characterization of miR-146a and miR-155 in blood, tissue and cell lines of head and neck squamous cell carcinoma patients and their impact on cell proliferation and migration

PURPOSE

Head and neck squamous cell carcinoma (HNSCC) is one of the most common malignancies worldwide with an unchanged 5-year survival rate during the last decade. To detect reliable prognostic markers and improve patients' outcome in future, the aim of our study was to detect differences in microRNA (miRNA; miR) expression profile and further on to analyze the functional role of selected miRNAs.

METHODS

Blood samples from HNSCC patients and sex- and age-matched healthy volunteers were analyzed by microarrays and validated by quantitative real-time PCR. Data were compared with tumor tissue results and all findings were correlated with clinical parameters. Additionally, the proliferation and migration potential of two cell lines transfected with miRNA mimics and inhibitors for miR-146a and miR-155 were examined.

RESULTS

Initial analysis of blood samples showed no significant differences between the miRNA profile of HNSCC patients and healthy controls (p > 0.05). Interestingly, down-regulation of miR-146a and miR-155 in blood of patients correlated with the occurrence of distant metastasis regarding tumor patients only (p = 0.023 and p = 0.028, respectively). Additionally, our investigations in tissue samples revealed a lower expression of miR-155 in tumor cells (p = 0.003) and a correlation with higher cT-classification for down-regulation of miR-146a (p = 0.005). Moreover, functional assays demonstrated that inhibition of miR-146a and miR-155 promoted dramatically proliferation and migration potential, whereas transfection of both mimics had an inhibitory effect.

CONCLUSIONS

Characterizing the expression of miR-146a and miR-155 and their functional role in tumor biology underlined significantly their proliferation and migration potential suggesting relevance as potential prognostic markers in HNSCC.

Identification of a novel miRNA-target gene regulatory network in osteosarcoma by integrating transcriptome analysis

Osteosarcoma remains a leading cause of cancer death in children and young adolescents. Although the introduction of multiagent chemotherapy, survival rates have not improved in two decades. Therefore, it is urgently needed to know the details regarding molecular etiology to driving therapeutic inroads for this disease. In this study we performed an integrated analysis of miRNA and mRNA expression data to explore the dysregulation of miRNA and miRNA-target gene regulatory network underlying OS. 59 differentially expressed miRNAs were identified, with 28 up-regulated and 31 down-regulated miRNAs by integrating OS miRNA expression data sets available. Using miRWalk databases prediction, we performed an anticorrelated analysis of miRNA and genes expression identified by a integrated analysis of gene expression data to identify 109 differently expressed miRNA target genes. A novel miRNA-target gene regulatory network was constructed with the miRNA-target gene pairs. miR-19b-3p, miR-20a-5p, miR-124-3p and their common target CCND2, the nodal points of regulatory network, may play important roles in OS. Bioinformatics analysis of biological functions and pathways demonstrated that target genes of miRNAs are highly correlated with carcinogenesis. Our findings may help to understand the molecular mechanisms of OS and identify targets of effective targeted therapies for OS.