PerioGlas®Regulates Osteoblast RNA Interfering

Long noncoding RNA Lnc-DIF inhibits bone formation by sequestering miR-489-3p

Osteoporosis has become a high incident bone disease along with the aging of human population. Long noncoding RNAs (LncRNAs) play an important role in osteoporosis incidence. In this study, we screened out an LncRNA negatively correlated with osteoblast differentiation, which was therefore named Lnc-DIF (differentiation inhibiting factor). Functional analysis proved that Lnc-DIF inhibited bone formation. A special structure containing multiple 53 nucleotide repeats was found in the trailing end of Lnc-DIF. Our study suggested that this repeat sequence could sequester multiple miR-489-3p and inhibit bone formation through miR-489-3p/SMAD2 axis. Moreover, siRNA of Lnc-DIF would rescue bone formation in both aging and ovariectomized osteoporosis mice. This study revealed a kind of LncRNA that could function as a sponge and regulate multiple miRNAs. RNA therapy techniques that target these LncRNAs could manipulate its downstream miRNA-target pathway with significantly higher efficiency and specificity. This provided potential therapeutic insight for RNA-based therapy for osteoporosis.

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Identified LncRNA Lnc-DIF that inhibited bone formation

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Lnc-DIF sequestered multiple miR-489-3p by the repeat sequences on its trailing end

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Lnc-DIF repeat sequence inhibited bone formation via miR-489-3p/SMAD2 axis

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Lnc-DIF siRNA showed strong capability on rescuing osteoporosis

Serum microRNAs in osteoporotic fracture and osteoarthritis: a genetic and functional study

The rising incidence of bone pathologies such as osteoporosis and osteoarthritis is negatively affecting the functional status of millions of patients worldwide. The genetic component of these multifactorial pathologies is far from being fully understood, but in recent years several epigenetic mechanisms involved in the pathophysiology of these bone diseases have been identified. The aim of the present study was to compare the serum expression of four miRNAs in women with hip fragility fracture (OF group), osteoarthritis requiring hip replacement (OA group) and control women (Ctrl group). Serum expression of miR-497-5p, miR-155-5p, miR-423-5p and miR-365-3p was determined in a sample of 23 OA women, 25 OF women and 52 Ctrl women. Data shown that women with bone pathologies have higher expression of miR-497 and miR-423 and lower expression of miR-155 and miR-365 than control subjects. Most importantly, miR-497 was identified as an excellent discriminator between OA group and control group (AUC: 0.89, p < 0.000) and acceptable in distinguishing from the OF group (AUC: 0.76, p = 0.002). Our data suggest that circulating miR-497 may represent a significant biomarker of OA, a promising finding that could contribute towards future early-stage diagnosis of this disease. Further studies are required to establish the role of miR-155, miR-423 and miR-365 in bone pathologies.

Knockdown of hsa_circ_0001275 reverses dexamethasone-induced osteoblast growth inhibition via mediation of miR-377/CDKN1B axis

BACKGROUND

Osteoporosis affects the quality of life among middle-aged and elderly individuals. In addition, dysfunction of osteoblasts can lead to the progression of osteoporosis. Circular (circ)RNAs are involved in various types of diseases, including osteoporosis. Moreover, it has been reported that hsa_circ_0001275 expression is upregulated in osteoporosis. However, the effects of hsa_circ_0001275 on the growth of osteoblasts remain unclear.

METHODS

In the present study, the gene and protein expression levels in hFOB1.19 cells were detected via reverse transcription-quantitative (RT-qPCR) and western blot analyses, respectively. In addition, alkaline phosphatase (ALP) activity and calcium nodules were examined by ALP and alizarin red staining, respectively. Cell proliferation was measured using the Cell Counting Kit-8 assay. Cell apoptosis and cell cycle were analyzed by flow cytometry. Furthermore, dual luciferase reporter and RNA pull-down assay were used to confirm the association among hsa_circ_0001275, microRNA (miR)-377 and CDKN1B.

RESULTS

DEX-induced hFOB1.19 cell growth inhibition was significantly reversed by silencing hsa_circ_0001275. Moreover, DEX significantly increased ALP activity and calcium nodules in hFOB1.19 cells, while this effect was significantly reversed in the presence of hsa_circ_0001275 small interfering RNA. In addition, miR-377 was sponged by hsa_circ_0001275 and CDKN1B was directly targeted by miR-377 in hFOB1.19 cells. Furthermore, the therapeutic effect of hsa_circ_0001275 knockdown on osteoporosis was notably reversed by miR-377 antagomir.

CONCLUSION

The data demonstrated that knockdown of hsa_circ_0001275 reversed DEX-induced osteoblast growth inhibition via activation of the miR-377/CDKN1B axis. Therefore, this study might shed new lights on the treatment of osteoporosis.

Up-regulation of microRNA-496 suppresses proliferation, invasion, migration and in vivo tumorigenicity of human osteosarcoma cells by targeting eIF4E

Osteosarcoma is an aggressive bone tumor characterized by a high level of genetic instability and recurring DNA deletions and amplifications. This study aims to investigate how microRNA-496 (miR-496) affects proliferation, invasion, and migration of human osteosarcoma (OS) cells and in vivo tumorigenicity by targeting eukaryotic translation initiation factor 4E (eIF4E). Microarray-based gene expression profiling involving OS was used in order to identify differentially expressed genes. After that, the interaction between miR-496 expression and OS patients' survival rate was determined. The expression pattern of miR-496 and eIF4E was determined in OS tissues and cells, and their potential relationship was further analyzed by using the dual luciferase reporter gene assay. With the purpose of identifying the functional role miR-496 in OS, cell proliferation, migration, and invasion were measured in cells treated with miR-496 mimic or inhibitor. A nude mouse model was constructed in order to investigate the regulatory effects of miR-496 on tumor growth in vivo by regulating eIF4E. OS cells exhibited a down-regulated expression of miR-496 and an up-regulated expression of eIF4E. miR-496 expression was positively correlated to OS patients' survival rate. Bioinformatics analysis suggested eIF4E would be a direct target of miR-496, and the expression of eIF4E was inhibited by overexpression of miR-496. miR-496 elevation was found to exert suppressive effects on OS cell proliferation, migration and invasion in vitro and tumor growth in vivo, with the effects being reversed using miR-496 depletion. Altogether, the above findings support a conclusion that miR-496 could work as a tumor suppressor in OS through down-regulation of eIF4E. This study may provide a novel target for treatment of OS.

Suppressing MicroRNA-30b by Estrogen Promotes Osteogenesis in Bone Marrow Mesenchymal Stem Cells

MicroRNAs (miRNAs) have been widely demonstrated to interact with multiple cellular signaling pathways and to participate in a wide range of physiological processes. Estradiol-17β (E2) is the most potent and prevalent endogenous estrogen that plays a vital role in promoting bone formation and reducing bone resorption. Currently, little is known about the regulation of miRNAs in E2-induced osteogenic differentiation. In the present study, the primary bone marrow mesenchymal stem cells from rats (rBMSCs) were isolated and incubated with E2, followed by miRNA profiling. The microarray showed that 29 miRNAs were differentially expressed in response to E2 stimulation. Further verification by real-time reverse-transcriptase polymerase chain reaction revealed that E2 enhanced the expression of let-7b and miR-25 but suppressed the miR-30b expression. Moreover, a gain-of-function experiment confirmed that miR-30b negatively regulated the E2-induced osteogenic differentiation. These data suggest an important role of miRNAs in osteogenic differentiation.

Global MicroRNA Profiling in Human Bone Marrow Skeletal-Stromal or Mesenchymal-Stem Cells Identified Candidates for Bone Regeneration

Bone remodeling and regeneration are highly regulated multistep processes involving posttranscriptional regulation by microRNAs (miRNAs). Here, we performed a global profiling of differentially expressed miRNAs in bone-marrow-derived skeletal cells (BMSCs; also known as stromal or mesenchymal stem cells) during in vitro osteoblast differentiation. We functionally validated the regulatory effects of several miRNAs on osteoblast differentiation and identified 15 miRNAs, most significantly miR-222 and miR-423, as regulators of osteoblastogenesis. In addition, we tested the possible targeting of miRNAs for enhancing bone tissue regeneration. Scaffolds functionalized with miRNA nano-carriers enhanced osteoblastogenesis in 3D culture and retained this ability at least 2 weeks after storage. Additionally, anti-miR-222 enhanced in vivo ectopic bone formation through targeting the cell-cycle inhibitor CDKN1B (cyclin-dependent kinase inhibitor 1B). A number of additional miRNAs exerted additive osteoinductive effects on BMSC differentiation, suggesting that pools of miRNAs delivered locally from an implanted scaffold can provide a promising approach for enhanced bone regeneration.

Applications of biomaterials for bone augmentation of jaws: clinical outcomes and in vitro studies

Partially or totally edentulous jaws frequently undergoes from moderate to severe bone atrophy with problems of prosthetic rehabilitation. The inability to make a prosthetic rehabilitation on implants may led to the use of a partial or total removable denture with difficulties in eating and speech, ulcerations of the oral mucosa and loss of facial vertical dimension. These problems may be solved performing bone augmentation procedures. Bone grafts and distraction osteogenesis brought implant dentistry from an experimental practice to become a consolidate dental procedure. Bone grafts, in particular, are currently a valuable treatment modality for the prosthetic rehabilitation. Numerous biomaterials have been developed for the rehabilitation of partially or totally edentulous jaws with fixed or removable dentures. The aim of this paper is to describe biomaterials for bone augmentation. Biomaterials are gradually resorbed by the osteoclasts and replaced by new bone formed through osteoblastic activity. Many biomaterials have been studied, but the most common are as follows: Allogro®, Algipore®, Osteobiol®, Peptide-15, Engipore®, Medpore®, Osteoplant®, Calcium sulfate, Perioglass®, Bio-Oss®, Calcium phosphate.

Upregulation of microRNA‑337 promotes the proliferation of endometrial carcinoma cells via targeting PTEN

Endometrial carcinoma (EC) is a common malignancy in females. MicroRNAs (miRs) are a class of non‑coding RNA that regulate a wide variety of cellular processes, and are important in the development of multiple types of malignancy. In the present study, cancerous and adjacent non‑cancerous normal tissue samples were collected from 24 patients diagnosed with EC. Reverse transcription quantitative polymerase chain reaction was performed on the tissue samples to determine the expression levels of six candidate miRs. These miRs have been previously reported to be differentially expressed in EC; however, the present study observed that only miR‑337 was differentially expressed. In addition, the current study identified phosphatase and tensin homolog (PTEN) as a target of miR‑337 using computational analysis and a luciferase assay. EC cells transfected with miR‑337 mimics and anti‑PTEN small interfering RNA demonstrated significantly decreased expression of PTEN, markedly increased proliferation and inhibition of cell apoptosis. The results indicate that miR‑337 is oncogenic in EC cells, as it suppresses PTEN expression. This may facilitate the development of miR‑based prevention or treatment strategies for EC.

Surgical management of mandibular central incisors with dumbbell shaped periapical lesion: a case report

Dental traumatic injuries may affect the teeth and alveolar bone directly or indirectly. Pulpal necrosis and chronic and apical periodontitis with cystic changes are the most common sequelae of the dental traumatic injuries, if the teeth are not treated immediately. This case report focuses on the conventional and surgical management of mandibular central incisors. A twenty-four-year-old male patient presented with pain in the mandibular central incisors. Radiographic examination revealed mandibular central incisors with dumbbell shaped periapical lesion. After root canal treatment, parendodontic surgery was performed for mandibular central incisors. After one-year recall examination, the teeth were asymptomatic and periapical lesion had healed.

Levels of HOXB7 and miR-337 in pancreatic ductal adenocarcinoma patients

Background

Many studies have revealed that homeobox-B7 (HOXB7) and miR-337 play important roles in different types of human cancers. However, the relationship of HOXB7 and miR-337 in PDAC with clinicopathological factors has not yet been examined and their biological roles remain to be explored.

Methods

Using quantitative real-time RT-PCR and immunohistochemical staining, the expression of HOXB7 mRNA, miR-337, and HOXB7 protein in 44 PDAC samples was detected. Survival curves were made using follow-up data. The relationship between clinical or pathological characteristics and the prognosis was analyzed.

Results

The expression levels of HOXB7 mRNA and HOXB7 protein were significantly elevated in PDAC samples than that in non-malignant adjacent tissues. There were obvious differences in HOXB7 mRNA and proteins between tumors of different diameters, differentiation, TNM stage, and lymph node status. The level of miR-337 was markedly lower in tumor samples than in non-malignant adjacent tissues. The expression of miR-337 was related to TNM stage and lymph node status. There were significant differences in survival curves between patients with tumors <4 cm in diameter and patients with tumors ≥4 cm, among groups of well, moderately, and poorly differentiated tumors, between groups with TNM stages I, II and III or IV, between groups with metastatic lymph nodes and non-metastatic lymph nodes, among groups of HOXB7 protein expression negative (or weak) and positive, between groups with low levels of miR-337 expression and with high levels of miR-337 expression. The levels of HOXB7 mRNA, HOXB7 protein, and miR-337 were found to be associated with longer survival.

Conclusion

The present study showed that HOXB7 was over-expressed and miR-337 was minimally expressed in PDAC tissues, and their levels were related to TNM stage and lymph node status. The levels of HOXB7 mRNA, HOXB7 protein, and miR-337 were associated with survival in PDAC patients. Results suggested that HOXB7 and miR-337 could be used as determinants of PDAC patient prognosis.

Virtual slides

The virtual slides for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1509730773118658.

Expression of microRNA-30c and its target genes in human osteoblastic cells by nano-bioglass ceramic-treatment

Osteoblast differentiation is tightly regulated by post transcriptional regulators such as microRNAs (miRNAs). Several bioactive materials including nano-bioglass ceramic particles (nBGC) influence differentiation of the osteoblasts, but the molecular mechanisms of nBGC-stimulation of osteoblast differentiation via miRNAs are not yet determined. In this study, we identified that nBGC-treatment stimulated miR-30c expression in human osteoblastic cells (MG63). The bioinformatics tools identified its regulatory network, molecular function, biological processes and its target genes involved in negative regulation of osteoblast differentiation. TGIF2 and HDAC4 were found to be its putative target genes and their expression was down regulated by nBGC-treatment in MG63 cells. Thus, this study advances our understanding of nBGC action on bone cells and supports utilization of nBGC in bone tissue engineering.

MicroRNA-337 is associated with chondrogenesis through regulating TGFBR2 expression

OBJECTIVE

MicroRNAs (miRNAs) have been implicated in regulating diverse cellular pathways and involved in development and inflammation. This study aimed to examine six miRNAs expression during the cartilage development and identify the key miRNA which is associated with chondrogenesis.

METHODS

The expression of six miRNAs in cartilage tissue during development was screened by real-time quantitative polymerase chain reaction (RT-qPCR). Rat models of bone matrix gelatin induced endochondral ossification, collagen-induced arthritis and pristane-induced arthritis were established to examine whether miR-337 is involved in chondrogenesis. Furthermore, the regulation of transforming growth factor-b type II receptor (TGFBR2) expression by miR-337 was determined with the luciferase reporter gene assay and Western blot. The expression of some specific genes relevant to cartilage tissue was tested by RT-qPCR after miR-337 mimic or inhibitor transfection.

RESULTS

MiR-337 expression was significantly down-regulated and almost disappeared in the maturation phases of endochondral ossification. The results of histology and RT-qPCR from three rat models showed that miR-337 is directly bound up with chondrogenesis. Furthermore, the results from the luciferase reporter gene assay and Western blot indicated that miR-337 regulated TGFBR2 expression. Our study also found that the enhancement of miR-337 may modulate the expression of cartilage-specific genes such as AGC1 in C-28/I2 chondrocytes.

CONCLUSION

We proved that miRNA-337 is associated with chondrogenesis through regulating TGFBR2 expression, and miRNA-337 can also influence cartilage-specific gene expression in chondrocytes. These findings may provide an important clue for further research in the arthritis pathogenesis and suggest a new remedy for arthritis treatment.

MicroRNA-423 promotes cell growth and regulates G(1)/S transition by targeting p21Cip1/Waf1 in hepatocellular carcinoma

MicroRNAs (miRNAs) are small non-coding RNA molecules that are often located in genomic breakpoint regions and can act as oncogenes or tumor suppressor genes in human cancer. Our previous study showed that microRNA-423 (miR-423), which localized to the frequently amplified region of chromosome 17q11, was upregulated in hepatocellular carcinoma (HCC). However, the potential functions and exact mechanistic roles of miR-423 in hepatic carcinogenesis remain unknown. Here, we demonstrated that miR-423 significantly promotes cell growth and cell cycle progression at the G(1)/S transition in HCC cells. In particular, we found that miR-423-3p contributes to these effects, whereas miR-423-5p does not. Further studies revealed that p21Cip1/Waf1 is a downstream target of miR-423 in HCC cells, as miR-423 bound directly to its 3' untranslated region and reduced both the messenger RNA and protein levels of p21Cip1/Waf1. Moreover, enforced expression of p21Cip1/Waf1 abrogated miR-423-induced effects on HCC cell proliferation and cell cycle progression. These findings indicate that miR-423 exerts growth-promoting effects in hepatic carcinogenesis through the suppression of tumor suppressor p21Cip1/Waf1 expression. The results of this study define miR-423 as a new oncogenic miRNA in HCC.

Ibandronate promotes osteogenic differentiation of periodontal ligament stem cells by regulating the expression of microRNAs

Bisphosphonates (BPs) have a profound effect on bone resorption and are widely used to treat osteoclast-mediated bone diseases. They suppress bone resorption by inhibiting the activity of mature osteoclasts and/or the formation of new osteoclasts. Osteoblasts may be an alternative target for BPs. Periodontal ligament stem cells (PDLSCs) exhibit osteoblast-like features and are capable of differentiating into osteoblasts or cementoblasts. This study aimed to determine the effects of ibandronate, a nitrogen-containing BP, on the proliferation and the differentiation of PDLSCs and to identify the microRNAs (miRNAs) that mediate these effects. The PDLSCs were treated with ibandronate, and cell proliferation was measured using the MTT (3-dimethylthiazol-2,5-diphenyltetrazolium bromide) assay. The expression of genes and miRNAs involved in osteoblastic differentiation was assayed using quantitative real-time reverse-transcription polymerase chain reaction (qRT-PCR). Ibandronate promoted the proliferation of PDLSCs and enhanced the expression of alkaline phosphatase (ALP), type I collagen (COL-1), osteoprotegerin (OPG), osteocalcin (OCN), and Runx2. The expression of miRNAs, including miR-18a, miR-133a, miR-141 and miR-19a, was significantly altered in the PDLSCs cultured with ibandronate. In PDLSCs, ibandronate regulates the expression of diverse bone formation-related genes via miRNAs. The exact mechanism underlying the role of ibandronate in osteoblasts has not been completely understood. Ibandronate may suppress the activity of osteoclasts while promoting the proliferation of osteoblasts by regulating the expression of miRNAs.

Molecular genetic studies of gene identification for osteoporosis: the 2009 update

Osteoporosis is a complex human disease that results in increased susceptibility to fragility fractures. It can be phenotypically characterized using several traits, including bone mineral density, bone size, bone strength, and bone turnover markers. The identification of gene variants that contribute to osteoporosis phenotypes, or responses to therapy, can eventually help individualize the prognosis, treatment, and prevention of fractures and their adverse outcomes. Our previously published reviews have comprehensively summarized the progress of molecular genetic studies of gene identification for osteoporosis and have covered the data available to the end of September 2007. This review represents our continuing efforts to summarize the important and representative findings published between October 2007 and November 2009. The topics covered include genetic association and linkage studies in humans, transgenic and knockout mouse models, as well as gene-expression microarray and proteomics studies. Major results are tabulated for comparison and ease of reference. Comments are made on the notable findings and representative studies for their potential influence and implications on our present understanding of the genetics of osteoporosis.

Microrna profiling analysis of differences between the melanoma of young adults and older adults

BACKGROUND

This study represents the first attempt to perform a profiling analysis of the intergenerational differences in the microRNAs (miRNAs) of primary cutaneous melanocytic neoplasms in young adult and older age groups. The data emphasize the importance of these master regulators in the transcriptional machinery of melanocytic neoplasms and suggest that differential levels of expressions of these miRs may contribute to differences in phenotypic and pathologic presentation of melanocytic neoplasms at different ages.

METHODS

An exploratory miRNA analysis of 666 miRs by low density microRNA arrays was conducted on formalin fixed and paraffin embedded tissues (FFPE) from 10 older adults and 10 young adults including conventional melanoma and melanocytic neoplasms of uncertain biological significance. Age-matched benign melanocytic nevi were used as controls.

RESULTS

Primary melanoma in patients greater than 60 years old was characterized by the increased expression of miRs regulating TLR-MyD88-NF-kappaB pathway (hsa-miR-199a), RAS/RAB22A pathway (hsa-miR-204); growth differentiation and migration (hsa-miR337), epithelial mesenchymal transition (EMT) (let-7b, hsa-miR-10b/10b*), invasion and metastasis (hsa-miR-10b/10b*), hsa-miR-30a/e*, hsa-miR-29c*; cellular matrix components (hsa-miR-29c*); invasion-cytokinesis (hsa-miR-99b*) compared to melanoma of younger patients. MiR-211 was dramatically downregulated compared to nevi controls, decreased with increasing age and was among the miRs linked to metastatic processes. Melanoma in young adult patients had increased expression of hsa-miR-449a and decreased expression of hsa-miR-146b, hsa-miR-214*. MiR-30a* in clinical stages I-II adult and pediatric melanoma could predict classification of melanoma tissue in the two extremes of age groups. Although the number of cases is small, positive lymph node status in the two age groups was characterized by the statistically significant expression of hsa-miR-30a* and hsa-miR-204 (F-test, p-value < 0.001).

CONCLUSIONS

Our findings, although preliminary, support the notion that the differential biology of melanoma at the extremes of age is driven, in part, by deregulation of microRNA expression and by fine tuning of miRs that are already known to regulate cell cycle, inflammation, Epithelial-Mesenchymal Transition (EMT)/stroma and more specifically genes known to be altered in melanoma. Our analysis reveals that miR expression differences create unique patterns of frequently affected biological processes that clearly distinguish old age from young age melanomas. This is a novel characterization of the miRnomes of melanocytic neoplasms at two extremes of age and identifies potential diagnostic and clinico-pathologic biomarkers that may serve as novel miR-based targeted modalities in melanoma diagnosis and treatment.

Global gene expression analysis for evaluation and design of biomaterials

Comprehensive gene expression analysis using DNA microarrays has become a widespread technique in molecular biological research. In the biomaterials field, it is used to evaluate the biocompatibility or cellular toxicity of metals, polymers and ceramics. Studies in this field have extracted differentially expressed genes in the context of differences in cellular responses among multiple materials. Based on these genes, the effects of materials on cells at the molecular level have been examined. Expression data ranging from several to tens of thousands of genes can be obtained from DNA microarrays. For this reason, several tens or hundreds of differentially expressed genes are often present in different materials. In this review, we outline the principles of DNA microarrays, and provide an introduction to methods of extracting information which is useful for evaluating and designing biomaterials from comprehensive gene expression data.