Osteosarcoma Cell Proliferation Research Articles

MiRNA-421 regulates proliferation, migration, and proinflammatory responses of human osteosarcoma cells by targeting monocyte chemotactic protein 1-induced protein 1 protein via magnetic nanoliposomes

Human osteosarcoma is difficult to treat successfully. Current research is mainly theoretical and about the treatment of the disease with miRNA is uncommon. This paper explores roles and mechanisms of miR-421 regulation of MCPIP1 in HOS cells. miR-421, delivered in magnetic nanoliposomes, modulated proliferation, migration, and proinflammatory responses of MG-63 cells in culture, as demonstrated using qRT-PCR. Effects of control, inhibition, and promotion plasmids containing miR-421 on MCPIP1 protein regulation were recorded after PA induction by observing the distribution of chromosomes in transfected cells. Further, miR-421 mimics induced MCPIP1 and TC production and lipid accumulation in HOS cells. Overexpression of miR-421 caused MG-63 cells to accumulate fibrosis marker proteins, including α-SMA, type I collagen, and type III collagen, and further reduced expression of MCPIP1 protein.

Vancomycin Containing PDLLA and PLGA/β-TCP Inhibit Biofilm Formation but Do Not Stimulate Osteogenic Transformation of Human Mesenchymal Stem Cells.

AimsChronic osteomyelitis, including implant-related prosthetic joint infection, is extremely difficult to cure. We develop vancomycin containing release systems from poly(d,l-lactide) (PDLLA) and poly(d,l-lactide-co-glycolide) (PLGA) composites with beta-tricalcium phosphate (β-TCP) to treat methicillin-resistant Staphylococcus aureus osteomyelitis. We ask whether vancomycin containing PDLLA/β-TCP and PLGA/β-TCP composites will prevent early biofilm formation, allow cell proliferation and osteogenic differentiation, and stimulate osteogenic signaling molecules in the absence of an osteogenic medium.MethodsComposites were produced and characterized with scanning electron microscopy. In vitro vancomycin release was assessed for 6 weeks. Biofilm prevention was calculated by crystal violet staining. Human bone marrow-derived mesenchymal stem cells (hBM-MSCs) and osteosarcoma cell (SaOS-2) proliferation and differentiation were assessed with water soluble tetrazolium salt and alkaline phosphatase (ALP) staining. Real-time quantitative polymerase chain reaction defined osteogenic signaling molecules for hBM-MSCs.ResultsTotally, 3.1 ± 0.2 mg and 3.4 ± 0.4 mg vancomycin released from PDLLA/β-TCP and the PLGA/β-TCP composites, respectively, and inhibited early biofilm formation. hBM-MSCs and SaOS-2 cells proliferated on the composites and stimulated ALP activity of cells. Runt-related transcription factor 2 (RUNX2) and SRY-Box transcription Factor 9 (SOX9) expressions were, however, lower with composites when compared with control.ConclusionVancomycin containing PDLLA/β-TCP and PLGA/β-TCP composites inhibited early biofilm formation and proliferated and differentiated hBM-MSCs and SaOS-2 cells, but osteogenesis-related RUNX2 and SOX9 transcription factors were not strongly expressed in the absence of an osteogenic medium for 14 days.

LINC01140 regulates osteosarcoma proliferation and invasion by targeting the miR-139-5p/HOXA9 axis

Osteosarcoma is one of the commonest metastatic tumor in children and teenagers, and has a hopeless, prognosis. Long non-coding RNA (lncRNA) acts momentous roles as a regulator on the proliferation and migration of cancer. Here, we performed GEO database analysis and qPCR to identify differentially expressed lncRNAs in osteosarcoma cells. Knockdown of lncRNA LINC01140 was used to detect the effect of LINC01140 on the proliferation, invasion, and epithelial-mesenchymal transition (EMT) of osteosarcoma cells. Bioinformatics analysis and qPCR identified the LINC01140/miR-139-5p/Homeobox A9 (HOXA9) regulatory axis. RNA immunoprecipitation assay, Dual-luciferase assay, and rescue experiments confirmed the interaction of LINC01140/miR-139-5p/HOXA9 in osteosarcoma. LINC01140 was overexpressed in osteosarcoma and knocking down LINC01140 restrained the proliferation and invasion of osteosarcoma cells and EMT. In Saos2 and MG63 cells, LINC01140 sponged miR-139-5p, and a miR-139-5p inhibitor overturned the suppression of LINC01140 knockdown on the proliferation and migration of osteosarcoma cells. Moreover, miR-139-5p depressed the invasion, proliferation, and EMT of osteosarcoma cells via targeting HOXA9. Our results indicate that LINC01140 downregulation inhibits the invasion, proliferation, and EMT in osteosarcoma cells through targeting the miR-139-5p/HOXA9 axis. Therefore, LINC01140 is a potential therapeutic target for osteosarcoma.

EBF1-mediated up-regulation of lncRNA FGD5-AS1 facilitates osteosarcoma progression by regulating miR-124-3p/G3BP2 axis as a ceRNA

BackgroundAs a skeletal malignancy, osteosarcoma has high incidence among primary malignant bone tumors. With increasing researches on molecules which mediate cancer progression, molecular mechanism has gradually become the pivot of osteosarcoma research and treatment.AimOur study aimed at investigating the function of G3BP stress granule assembly factor 2 (G3BP2), which is an oncogene for breast cancer (BC) and prostate cancer but remains unknown in osteosarcoma cells.MethodsRelated gene expression was confirmed by RT-qPCR. Functional assays including immunofluorescence (IF), colony formation, transferase-mediated dUTP nick-end labeling (TUNEL) as well as transwell assays were utilized to test the cell biological process caused by the genes. Meanwhile, RNA pull-down assay, along with luciferase reporter and RNA immunoprecipitation (RIP) assays, was utilized to detect the interaction G3BP2, miR-124-3p and FGD5 antisense RNA 1 (FGD5-AS1) may exert on the regulation of osteosarcoma cells.ResultsG3BP2 was with high expression in osteosarcoma cells, and it aggravated the malignant cell behaviors in osteosarcoma. Additionally, miR-124-3p was verified to negatively regulate G3BP2 expression in osteosarcoma cells. Moreover, lncRNA FGD5-AS1 was predicted and testified to be the sponge of miR-124-3p and modulated G3BP2 expression positively. Subsequently, FGA5-AS1 accelerated osteosarcoma cell proliferation through up-regulating G3BP2. Furthermore, we identified EBF transcription factor 1 (EBF1) as the transcription factor for FGA5-AS1, and EBF1 served as a tumor facilitator in osteosarcoma cells.ConclusionEBF1 induced-FGA5-AS1 aggravated osteosarcoma cell malignancy by targeting miR-124-3p and G3BP2.

Doxorubicin and SN-38 inhibit the proliferation of osteosarcoma cells by inducing cell cycle arrest

Osteosarcoma is the most common highly malignant primary bone tumor in adolescents and it has a poor prognosis. The aim of the present study was to explore potential chemotherapy drugs for osteosarcoma, in order to provide a theoretical basis for the clinical treatment of the disease. Senescence-associated β-galactosidase (SA-β-gal) staining was used to detect the senescence of drug-treated cells. Bromodeoxyuridine(BRDU) and other methods were used to detect cell proliferation. Immunoprecipitation, immunofluorescence and other techniques were used to explore the impact of drug treatment on the cell cycle. In the present study, doxorubicin (Dox) and 7-ethyl-10-hydroxycamptothecin (SN-38) were found to induce osteosarcoma cell senescence, and senescent cells exhibit the senescence-associated heterochromatin foci phenomenon (SAHF). Cell senescence is induced in osteosarcoma by Dox and SN-38 through inhibiting the expression of the cell cycle-related genes cyclin-dependent kinase (CDK)4, cyclin D1, CDK2 and cyclin E, and inhibit the formation of cell cycle-dependent complexes CDK4/cyclin D1 and CDK2/cyclin E. Eventually, Dox and SN-38 cause cell cycle arrest and induce cell senescence.

Allicin Inhibits Osteosarcoma Growth by Promoting Oxidative Stress and Autophagy via the Inactivation of the lncRNA MALAT1-miR-376a-Wnt/β-Catenin Signaling Pathway.

Allicin, an organic sulfur compound extracted from the bulb of Allium sativum, can potentially prevent various tumors. Our previous study found that allicin can effectively suppress the proliferation of osteosarcoma cells. However, the molecular mechanisms have not been illustrated. In this study, Saos-2 and U2OS osteosarcoma cells were used to investigate the underlying mechanisms. A series of experiments were carried out to authenticate the anticancer property of allicin. Knockdown of lncRNA MALAT1 inhibited the proliferation, invasion and migration and promoted apoptosis of osteosarcoma cells. Knockdown of miR-376a increased the proliferation, invasion, and migration and dropped apoptosis of osteosarcoma cells. Furthermore, knockdown of miR-376a reversed the influences of MALAT1 silencing in osteosarcoma cells. Based on our data, MALAT1 could downregulate the expression of miR-376a, subsequently accelerating osteosarcoma. Moreover, oxidative stress and autophagy were identified as the potential key pathway of allicin. Allicin inhibited osteosarcoma growth and promoted oxidative stress and autophagy via MALATI-miR-376a. We also found that allicin promotes oxidative stress and autophagy to inhibit osteosarcoma growth by inhibiting the Wnt/β-catenin pathway in vivo and in vitro. All data showed that allicin promotes oxidative stress and autophagy of osteosarcoma via the MALATI-miR-376a-Wnt/β-catenin pathway.

Downregulation of hsa_circ_0000885 suppressed osteosarcoma metastasis and progression via regulating E2F3 expression and sponging miR-16-5p.

IntroductionAccumulating evidence has shown that circular RNAs (circRNAs) have indispensable functions during tumor progression by regulating gene expression. A previous study found that upregulation of hsa_circ_0000885 indicated a poor clinical outcome of osteosarcoma (OS). However, the regulatory mechanism of this process is unclear.MethodsThis investigation aimed to elucidate how hsa_circ_0000885 regulated OSs. The study used RT-qPCR to investigate hsa_circ_0000885 expression in OS cells. We conducted luciferase reporter assays and analyses to confirm the hsa_circ_0000885 downstream target. We transfected OS cells using different vectors and used Transwell migration, colony formation, western blotting, Matrigel invasion, proliferation, in vivo tumorigenesis, and metastasis assays to identify the role of hsa_circ_0000885 in OS.ResultsThe results showed that hsa_circ_0000885 expression altered OS cell lines, and that hsa_circ_0000885 downregulation suppressed OS cell proliferation and invasion using in vivo and in vitro experiments. Luciferase reporter assays verified that miR-16-5p and E2F3 were downstream targets of hsa_circ_0000885. E2F3 overexpression or miR-16-5p inhibition reversed OS cell invasion and proliferation after silencing hsa_circ_0000885. Furthermore, hsa_circ_0000885 affected cancer stem cell differentiation by regulating miR-16-5p/E2F3.ConclusionsOverall, the results showed that hsa_circ_0000885 downregulation suppressed OS progression and metastasis via regulating E2F3 expression and sponging miR-16-5p.

Overexpression Pattern of miR-301b in Osteosarcoma and Its Relevance with Osteosarcoma Cellular Behaviors via Modulating SNX10.

Prior studies have noted the importance of microRNAs (miRNAs) in development and progression of osteosarcoma (OS), but the influence of miR-301b is less investigated. This investigation aimed to explore the biological role of miR-301b/SNX10 in OS. GSE28423 and GSE28424 arrays delivered the corresponding miR-301b and sorting nexin 10 (SNX10) expression levels in OS samples. miR-301b and SNX10 expressions were also measured by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting in cells. Cell counting kit (CCK)-8 and transwell analysis were applied to measure cell characteristics. Luciferase reporter assay and Pearson correlation analysis were used to detect the relevance between miR-301b and SNX10. miR-301b was extremely increased in OS tissues compared with normal tissues, while SNX10 was decreased. The proliferation, invasion, and migration capabilities were limited following a low expression level of miR-301b whereas miR-301b overexpression promoted cellular malignant behaviors. miR-301b negatively targeted SNX10. The elevated SNX10 expression highlighted the inhibitory function on cell proliferation, migration, and invasion in OS cells treated by miR-301b inhibitor. Reduction of miR-301b induced the decrease of epithelial-mesenchymal transition (EMT)-related markers including N-cadherin, Vimentin, and matrix metallo-proteinase 9 (MMP)9. These results are added to the complete expanding field of the potential effects of miR-301b in OS cell malignant behaviors and demonstrate its promising role for further use to treat human OS.

Enhancing structural strength and improving cell survival through Polycaprolactone/(gelatin/hydroxyapatite) Core‐Shell nanofibers for tissue engineering

AbstractBone tissue engineering is a practical approach to repairing broken or damaged bones that combines scaffold, cells, and growth factors for treatment. In this study, polycaprolactone (PCL)/gelatin (Ge)/hydroxyapatite (HA) core‐shell nanocomposites have been produced by the coaxial electrospinning method. Coaxial electrospinning is an efficient method for scaffold preparation to provide an interconnected porous fibrous scaffold. The prepared nanocomposite simultaneously benefited from the good mechanical behavior of the core PCL polymer. The desired biological properties also originated from the outer layer of the Ge/HA nanocomposite. Nanofibrous scaffolds' properties were characterized using SEM, TEM, FTIR, TGA, DSC, tensile test, contact angle, and MTT assay. The morphology of the as‐electrospun nanofibers was investigated using SEM and TEM, which revealed a defect‐less fibrous morphology. TEM images showed the core‐shell structure of the prepared scaffold nanofibers. The contact angle test showed that the presence of HA nanoparticles has improved the wettability of fibrous composites. In addition, HA nanoparticles could effectively strengthen the polymer scaffolds. The highest UTS value of 4.1 MPa was obtained in the PCL/(Ge+10%HA) sample. The cytotoxicity results revealed that the prepared scaffolds were utterly biocompatible. Moreover, significant cell proliferation of osteosarcoma cells was observed at high HA contents. The interconnected pores allowed cells to migrate into the scaffolds and grow inside. Based on the obtained results, PCL/(Ge/ HA) core‐shell nanofibers could be a promising candidate for bone scaffolds.

HIF-1α-mediated augmentation of miRNA-18b-5p facilitates proliferation and metastasis in osteosarcoma through attenuation PHF2

Extensive evidence has explored the involvement of microRNAs (miRNAs) in osteosarcoma (OS). Limitedly, the concrete function of microRNA-18b-5p (miR-18b-5p) in OS remains unexplored and largely elusive. Here, we validated that miR-18b-5p significantly elevated in OS via analyzing the data from GEO database. The results showed that miR-18b-5p was overexpressed in human OS tissues and cell lines. The clinical evidence suggested that high level of miR-18b-5p was negatively correlated with the poor prognosis of OS. Meanwhile, miR-18b-5p upregulation facilitated the proliferation and metastasis of OS cells in vitro and in vivo. The mechanism exploration demonstrated that miR-18b-5p acted as a potential inhibitor of PHF2, a tumor suppressor gene, at post-transcriptional level. Moreover, hypoxia induced gene expression of miR-18b-5p was clarified to be transcriptionally mediated by HIF-1α. The clinicopathological analysis in samples of OS patients further supported that miR-18b-5p had a positive correlation with HIF-1α expression, and negative correlation with PHF2. Collectively, the present study uncovered a new molecular mechanism of OS tumorigenesis and development and miR-18b-5p might be a prognostic biomarker and potential therapeutic target for OS treatment.

Osteosarcoma Cell-Derived Exosomal ELFN1-AS1 Mediates Macrophage M2 Polarization via Sponging miR-138-5p and miR-1291 to Promote the Tumorgenesis of Osteosarcoma.

BackgroundExosomes play an important role in cell-cell communication by transferring genetic materials such as long non-coding RNAs (lncRNAs) between cancer cells and tumor-associated macrophages (TAMs) in the tumor microenvironment (TME). Recent studies revealed that lncRNA ELFN1-AS1 could function as an oncogene in many human cancers. However, the role of extracellular lncRNA ELFN1-AS1 in cell-to-cell communication of osteosarcoma (OS) has not been fully investigated.MethodsFunctional studies, including CCK-8, EdU staining and transwell assay were performed to investigate the role of ELFN1-AS1 in the progression of OS. 143B via xenograft mouse model was established to assess the role of ELFN1-AS1 in vivo. In addition, transmission electron microscopy (TEM) and real-time quantitative PCR (RT-qPCR) assay were used to verify the existence of exosomal ELFN1-AS1.ResultsThe level of ELFN1-AS1 was markedly upregulated in patients with advanced OS and in OS cells. In addition, overexpression of ELFN1-AS1 significantly promoted the proliferation, migration and invasion of OS cells, while knockdown of ELFN1-AS1 exhibited the opposite effects. Meanwhile, ELFN1-AS1 could be transferred from OS cells to macrophages via exosomes. Exosomal ELFN1-AS1 from 143B cells was able to promote macrophage M2 polarization, and M2 macrophage in return facilitated OS progression. Mechanistically, overexpression of ELFN1-AS1 upregulated CREB1 level via sponging miR-138-5p and miR-1291 in macrophage via.ConclusionOS cell-derived exosomal ELFN1-AS1 was able to induce macrophage M2 polarization via sponging miR-138-5p and miR-1291, and M2 macrophage notably facilitated the progression of OS. These data suggested that ELFN1-AS1 might serve as a potential therapeutic target for osteosarcoma.

Lentivirus-induced knockdown of IARS2 expression inhibits the proliferation and promotes the apoptosis of human osteosarcoma cells.

Isoleucyl-tRNA synthetase 2 (IARS2), distributed in mitochondria, is an IARS involved in protein synthesis. Notably, IARS2 has been reported to be associated with tumor progression; however, the relationship between osteosarcoma (OS) and IARS2 remains unclear. To investigate the role of IARS2 in human OS, the expression and relationship of IARS2 with survival were firstly analyzed using the Gene Expression Profiling Interactive Analysis 2 database. Subsequently, an IARS2-short hairpin RNA lentiviral vector was established and used to infect the MNNG/HOS and U2OS cell lines. Reverse transcription-quantitative PCR (RT-qPCR) and western blotting were applied to determine the efficiency of IARS2 knockdown. The effects of IARS2 knockdown on cell proliferation, colony formation and apoptosis were evaluated by Celigo, MTT assays, colony formation assays and flow cytomeric analysis. In the present study, IARS2 tends to be high expressed in OS tissue and was associated with survival but this was not significant. The results of RT-qPCR and western blotting showed that the expression of IARS2 was effectively knocked down in the MNNG/HOS and U2OS cell lines. Celigo, MTT and colony formation assays showed that IARS2 knockdown in MNNG/HOS and U2OS cell lines inhibited cell proliferation and colony formation compared with in the control group. Flow cytometric analysis revealed that IARS2 knockdown increased apoptosis. These results suggested that IARS2 may be critical for the proliferation and apoptosis of OS cells.

KLF5-induced miR-487a augments the progression of osteosarcoma cells by targeting NKX3-1 in vitro.

MicroRNAs (miRNAs or miRs) are involved in the development and progression of numerous types of cancer however their role in osteosarcoma has not been fully clarified. The present study aimed to use high-throughput bioinformatics analysis as well as in vitro experiments to investigate the potential role of transcription factors, miRNAs and their targets in the progression of osteosarcoma. miRNA data and clinical information of osteosarcoma were obtained from Gene Expression Omnibus database to investigate differentially expressed miRNAs. The expression of miRNAs/mRNAs in osteosarcoma cell lines was detected via reverse transcription-quantitative (RT-qPCR). MTT and colony formation assay were used to determine cell proliferation ability and transwell assay was used to observe cell invasion and migration ability. A total of four prediction algorithms for miRNA-mRNA interactions were used to determine potential target genes of miR-487a. Predicted target genes were used to intersect with overlapped differentially expressed genes (DEGs) from GSE12865 and The Cancer Genome Atlas osteosarcoma datasets. Expression of NK3 homeobox 1 (NKX3-1) was analyzed by western blotting and RT-qPCR assay. Dual luciferase assay was conducted to verify whether NKX3-1 was a direct target of miR-487a. The regulatory association between Kruppel-like factor 5 (KLF5) and miR-487a was detected using chromatin immunoprecipitation assay. miR-487a was upregulated in osteosarcoma tissue (GSE65071 and GSE28423) and cell lines (HOS and MG63). miR-487a mimic promoted proliferation, migration and invasion of osteosarcoma cells. NKX3-1 was a direct target of miR-487a and transfection of NKX3-1 plasmid reversed the effect of miR-487a on proliferation, migration and invasion of osteosarcoma cells. KLF5 enhanced miR-487a expression by directly binding to its promoter region and miR-487a inhibitor reversed the effect of KLF5 on proliferation, migration and invasion of osteosarcoma cells. The present results indicated that KLF5/miR-487a signaling promoted invasion and metastasis of osteosarcoma cells via targeting NKX3-1.

Polydatin Incorporated in Polycaprolactone Nanofibers Improves Osteogenic Differentiation.

Polycaprolactone nanofibers are used as scaffolds in the field of tissue engineering for tissue regeneration or drug delivery. Polycaprolactone (PCL) is a biodegradable hydrophobic polyester used to obtain implantable nanostructures, which are clinically applicable due to their biological safety. Polydatin (PD), a glycosidic precursor of resveratrol, is known for its antioxidant, antitumor, antiosteoporotic, and bone regeneration activities. We aimed to use the osteogenic capacity of polydatin to create a biomimetic innovative and patented scaffold consisting of PCL-PD for bone tissue engineering. Both osteosarcoma cells (Saos-2) and mesenchymal stem cells (MSCs) were used to test the in vitro cytocompatibility of the PD-PCL scaffold. Reverse-phase (RP) HPLC was used to evaluate the timing release of PD from the PCL-PD nanofibers and the MTT assay, scanning electron microscopy, and alkaline phosphatase (ALP) activity were used to evaluate the proliferation, adhesion, and cellular differentiation in both osteosarcoma and human mesenchymal stem cells (MSCs) seeded on PD-PCL nanofibers. The proliferation of osteosarcoma cells (Saos-2) on the PD-PCL scaffold decreased when compared to cells grown on PLC nanofibers, whereas the proliferation of MSCs was comparable in both PCL and PD-PCL nanofibers. Noteworthy, after 14 days, the ALP activity was higher in both Saos-2 cells and MSCs cultivated on PD-PCL than on empty scaffolds. Moreover, the same cells showed a spindle-shaped morphology after 14 days when grown on PD-PCL as shown by SEM. In conclusion, we provide evidence that nanofibers appropriately coated with PD support the adhesion and promote the osteogenic differentiation of both human osteosarcoma cells and MSCs.

Retraction: MicroRNA-153 Inhibits Osteosarcoma Cells Proliferation and Invasion by Targeting TGF-β2.

Retraction: MicroRNA-153 Inhibits Osteosarcoma Cells Proliferation and Invasion by Targeting TGF-β2.

MiR-29a-3p mitigates the development of osteosarcoma through modulating IGF1 mediated PI3k/Akt/FOXO3 pathway by activating autophagy

ABSTRACT Osteosarcoma (OS), occurring in mesenchymal tissues and with a high degree of malignancy, is most common in children and adolescents. At present, we intend to figure out the expression and functions of miR-29a-3p in OS development. Reverse transcription-polymerase chain reaction (RT-PCR) was adopted to monitor the expression of miR-29a-3p and IGF1 in OS tissues and adjacent non-tumor tissues. Then, the 3- (4,5)-dimethylthiahiazo (-z-y1)-3,5-di- phenytetrazoliumromide (MTT) assay, colony formation experiment, western blot and Transwell assay were conducted to validate OS cell proliferation, colony formation ability, apoptosis, migration and invasion. Next, the association between miR-29a-3p and IGF1 was corroborated by the dual-luciferase reporter assay and the Pearson correlation analysis. Finally, WB was implemented to test the levels of autophagy-related proteins LC3-I/LC3-II, Beclin-1, p62, and the IGF-1 R/PI3k/Akt/FOXO3 axis in OS cells. As a result, miR-29a-3p was down-regulated in OS tissues (versus adjacent non-tumor tissues) and OS cell lines. Overexpressing miR-29a-3p aggravated apoptosis, dampened cell proliferation, colony formation, migration and invasion, and promoted autophagy of OS cells. IGF1 was identified as a target of miR-29a-3p. IGF1 induced oncogenic effects in OS by activating IGF-1 R/ PI3k/Akt pathway, and it dampened the tumor-suppressive effect of miR-29a-3p on OS. Taken together, miR-29a-3p repressed the OS evolvement through inducing autophagy and inhibiting IGF1 mediated PI3k/Akt/FOXO3 pathway.

Circ_0051079 silencing inhibits the malignant phenotypes of osteosarcoma cells by the TRIM66/Wnt/β-catenin pathway in a miR-625-5p-dependent manner

BackgroundCircular RNA (circRNA) is a newly-discovered endogenous transcript that has been reported to participate in osteosarcoma (OS) progression. However, the underlying mechanism of circ_0051079 modulating OS development remains unclear. MethodsRNA expressions of circ_0051079, miR-625-5p and tripartite motif containing 66 (TRIM66) were detected by quantitative real-time polymerase chain reaction. Protein expression was checked by Western blot analysis. The functional effects of circ_0051079 on OS cell malignancy were investigated by cell counting kit-8, clonogenicity, transwell, tube formation and flow cytometry assays. The interactions among circ_0051079, miR-625-5p and TRIM66 were identified by dual-luciferase reporter and RNA immunoprecipitation assays. Mouse xenograft model assay was performed to elucidate the effects of circ_0051079 knockdown on tumor formation in vivo. ResultsCirc_0051079 and TRIM66 expressions were significantly upregulated, but miR-625-5p was downregulated in OS tissues and cells compared with control groups. Circ_0051079 expression was significantly associated with tumor-node-metastasis stage and tumor size of OS patients. Circ_0051079 knockdown inhibited OS cell proliferation, migration and invasion, repressed angiogenesis but induced cell apoptosis, accompanied by the decreases of PCNA and Bcl-2 production and an increase of Bax production. MiR-625-5p, a target miRNA of circ_0051079, participated in regulating circ_0051079-induced effects. Also, TRIM66 was identified as a target mRNA of miR-625-5p, and partially attenuated the inhibitory effects of miR-625-5p in OS cells. Circ_0051079 modulated the Wnt/β-catenin pathway through TRIM66 in vitro. Importantly, circ_0051079 silencing reduced TRIM66 expression by interacting with miR-625-5p. Further, circ_0051079 depletion inhibited tumor formation in vivo. ConclusionCirc_0051079 regulated OS development by the miR-625-5p/TRIM66/Wnt/β-catenin pathway, providing a novel therapeutic target for OS.

Acacetin inhibits the tumor growth of human osteosarcoma cells through regulating Wnt/β-catenin and JNK signaling pathways

• Acacetin weakens the proliferation, migration and invasion of osteosarcoma cells. • Acacetin promotes the apoptosis of osteosarcoma cells. • Xenograft mouse osteosarcoma model confirms the inhibitory effect in vivo . • The signal pathway is predicted by network pharmacology and confirmed by the experiments. Osteosarcoma (OS) is the most common primary malignant bone tumor with high lung metastasis and mortality rate. Neo-adjuvant chemotherapy combined with limb salvage is the main treatment strategy for OS. However, because of the tolerance to conventional chemotherapy and the cell toxicity of chemotherapy drugs, new drugs with lower toxicity for OS are urgently needed. Acacetin is a natural flavonoid compound that has inhibitory effects on many kinds of tumors. Herein, we explored the impact of acacetin on OS cell growth in vitro and in vivo . We discovered that acacetin suppressed the proliferation, migration and invasion, while promoted the apoptosis of OS cells. Notably, acacetin had little impact on proliferation and apoptosis of human normal cells. Furthermore, we confirmed that acacetin repressed the growth and metastasis of OS in xenograft mouse model in vivo . Mechanically, we discovered that acacetin activated JNK pathway and inactivated Wnt/β-catenin pathway. β-catenin over-expression or JNK inhibitor SP600125 was able to partially neutralize acacetin-induced inhibitory effect on OS cells. To sum up, our study implies that acacetin may inhibit tumor growth of human OS cells through regulating Wnt/β-catenin and JNK signaling pathways.

MicroRNA miR-331-3p suppresses osteosarcoma progression via the Bcl-2/Bax and Wnt/β-Catenin signaling pathways and the epithelial-mesenchymal transition by targeting N-acetylglucosaminyltransferase I (MGAT1)

ABSTRACT Osteosarcoma (OS) is a high-grade malignant disease that is a prevalent primary malignant sarcoma of the bone. The purpose of this investigation was to therefore elucidate the association between miR-331-3p and OS development and to identify a potential underlying mechanism. Key genes involved in OS were selected using GSE65071 dataset from the Gene Expression Omnibus (GEO) database and Gene Expression Profiling Interactive Analysis (GEPIA). Reverse transcription quantitative polymerase chain reaction (RT-qPCR) and Western blotting were conducted to detect miR-331-3p, MGAT1, the epithelial-mesenchymal transition (EMT), Bcl-2/Bax and Wnt/β-Catenin signaling pathways related proteins. Dual-luciferase reporter assay and TargetScan were used for validating interaction between MGAT1 mRNA and miR-331-3p. Biological effects of miR-331-3p and MGAT1 on OS cells were detected employing MTT, Transwell, wound healing and flow cytometry, respectively. MiR-331-3p was under-expressed in OS, and up-regulation or inhibition of its expression could significantly inhibit or promote the malignant phenotypes of OS cells. Furthermore, we found that MGAT1, a target of miR-331-3p, had elevated expression in OS. Interestingly, MGAT1 could partially alleviate the effect of miR-331-3p in vitro. Collectively, miR-331-3p acts as an critical tumor suppressor through inhibiting MGAT1, results in suppressed Wnt/β-Catenin pathway and decreased proliferation of OS cells; leads to increased apoptosis via Bcl-2/Bax pathway and inhibited migration and invasion ability via the EMT.

Therapeutic Effects of Zoledronic Acid-Loaded Hyaluronic Acid/Polyethylene Glycol/Nano-Hydroxyapatite Nanoparticles on Osteosarcoma.

Zoledronic acid (ZOL) has been approved as the only bisphosphonate for the prevention and treatment of metastatic bone diseases with acceptable safety and tolerability. However, systemic or direct injection of ZOL often causes severe side effects, which limits its clinical application. Here, an innovative nano-drug delivery system, ZOL-loaded hyaluronic acid/polyethylene glycol/nano-hydroxyapatite nanoparticles (HA-PEG-nHA-ZOL NPs), has been found to effectively inhibit the proliferation of three types of human osteosarcoma cell lines (143b, HOS, and MG63) at 1–10 μmol/L, while with low cell cytotoxicity on normal cells. The NPs significantly enhanced the apoptosis-related protein expression and tumor cell apoptosis rate. The NPs could also inhibit the proliferation of osteosarcoma cells by blocking the S phase of the cell cycle. In the orthotopic osteosarcoma nude mice model, local injection of the HA-PEG-nHA-ZOL NPs stimulated tumor necrosis, apoptosis, and granulocyte infiltration in the blood vessels. Altogether, the ZOL nano-delivery system possesses great potential for local treatment to prevent local tumor recurrence and can be applied in clinical osteosarcoma therapy.