On Osteosarcoma Cells Research Articles

CLG promotes mTOR/ULK1 pathway-mediated autophagy to inhibit OS development by inhibiting TRAF6-mediated FLT3 ubiquitination.

Corilagin (CLG) has antitumor activities in certain human malignant cancers. Herein, the effects and mechanisms of CLG on osteosarcoma (OS) were investigated. OS cell viability and proliferation were detected by MTT and colony formation assay. Cell cycle and apoptosis were examined using flow cytometry. The interaction between TRAF6 and FLT3 was investigated using a co-immunoprecipitation assay. Results demonstrated that CLG treatment inhibited OS cell viability and proliferation but promoted OS cell autophagy and apoptosis in a concentration-dependent manner. Mechanically, CLG inhibited TRAF6-mediated FLT3 ubiquitination degradation. TRAF6 overexpression abolished the effects of CLG on OS cell proliferation, autophagy, and apoptosis. Finally, CLG administration inhibited OS tumor growth in mice by inducing autophagy-dependent apoptosis. Taken together, CLG inhibited OS progression by facilitating mTOR/ULK1 pathway-mediated autophagy through inhibiting TRAF6-mediated FLT3 ubiquitination, which indicated that CLG was a promising candidate for the treatment of OS.

Analysis of the effects of M2 macrophage-derived PDE4C on the prognosis, metastasis and immunotherapy benefit of osteosarcoma.

Tumour-associated macrophages (TAMs), encompassing M1 and M2 subtypes, exert significant effects on osteosarcoma (OS) progression and immunosuppression. However, the impacts of TAM-derived biomarkers on the progression of OS remains limited. The GSE162454 profile was subjected to single-cell RNA (scRNA) sequencing analysis to identify crucial mediators between TAMs and OS cells. The clinical features, effects and mechanisms of these mediators on OS cells and tumour microenvironment were evaluated via biological function experiments and molecular biology experiments. Phosphodiesterase 4C (PDE4C) was identified as a pivotal mediator in the communication between M2 macrophages and OS cells. Elevated levels of PDE4C were detected in OS tissues, concomitant with M2 macrophage level, unfavourable prognosis and metastasis. The expression of PDE4C was observed to increase during the conversion process of THP-1 cells to M2 macrophages, which transferred the PDE4C mRNA to OS cells through exosome approach. PDE4C increased OS cell proliferation and mobility via upregulating the expression of collagens. Furthermore, a positive correlation was observed between elevated levels of PDE4C and increased TIDE score, decreased response rate following immune checkpoint therapy, reduced TMB and diminished PDL1 expression. Collectively, PDE4C derived from M2 macrophages has the potential to enhance the proliferation and mobility of OS cells by augmenting collagen expression. PDE4C may serve as a valuable biomarker for prognosticating patient outcomes and response rates following immunotherapy.

Diallyl trisulfide inhibits osteosarcoma 143B cell migration, invasion and EMT by inducing autophagy

BackgroundDiallyl trisulfide (DATS), a compound derived from garlic, has been demonstrated its anti-cancer properties. While it has been shown to inhibit the expression of epidermal growth factor receptor (EGFR) in various cancers, its effects on osteosarcoma (OS) cells remain unclear. This study aimed to investigate the impacts of DATS on OS cells growth, migration, invasion, epithelial-mesenchymal transition (EMT) and autophagy, as well as its underlying mechanisms which was involving in the EGFR/PI3K/AKT/mTOR pathway. MethodsIn this study, human osteosarcoma cells (143B) were treated with different concentrations of DATS (10, 50, 100 and 200 μM) for 24 and 48 h, respectively. Cell viability was measured using CCK8, the half lethal concentration was selected for the following experiments. Wound healing and transwell assays were performed to evaluate migration and invasion abilities, while flow cytometry was used to measure apoptosis. Quantitative reverse transcription polymerase chain reaction (qRT-PCR), Western blotting, and confocal imaging were employed to analyze the related mRNA and protein expression levels of epithelial-mesenchymal transition (EMT), EGFR/Phosphoinositide 3 kinase (PI3K)/AKT/Mammalian target of rapamycin (mTOR) signaling pathway and autophagy-related markers. ResultsDATS significantly inhibited proliferation, migration and EMT in osteosarcoma cells. Additionally, DATS promoted cell apoptosis and induced autophagy, which could be rescued by the autophagy inhibitor 3-methyladenine (3-MA). Moreover, DATS treatment led to the inactivation of the EGFR/PI3K/AKT/mTOR pathway in osteosarcoma cells. ConclusionsThis study demonstrated that DATS inhibited osteosarcoma cell growth, migration and EMT, but inducing apoptosis and autophagy. These effects were mediated by the inactivation of the EGFR/PI3K/AKT/mTOR signaling pathway. These findings suggested that DATS could serve as a potential therapeutic agent for osteosarcoma treatment.

M6A-modified circARHGAP12 promotes the aerobic glycolysis of doxorubicin-resistance osteosarcoma by targeting c-Myc

Chemotherapy resistance accompanied by energy metabolism abnormality functions as one of the main reasons for treatment failure and poor prognosis. However, the function of N6-methyladenosine (m6A)-modified circular RNA (circRNA) on osteosarcoma (OS) is still unclear. Here, present research investigated the potential role and mechanism of circARHGAP12 on OS doxorubicin (Dox) resistance and aerobic glycolysis. Results indicated that circARHGAP12 was a novel m6A-modified circRNA, which was up-regulated in OS cells. Overexpression of circARHGAP12 promoted the Dox resistance half-maximal inhibitory concentration (IC50) and aerobic glycolysis (glucose uptake, lactate and ATP production) in OS cells (Saos-2/Dox, MG63/Dox). Mechanistically, m6A-modified circARHGAP12 could bind with c-Myc mRNA through m6A-dependent manner, thereby enhancing the c-Myc mRNA stability. Thus, these findings revealed the critical function of circARHGAP12 on OS Dox-resistance and aerobic glycolysis. Taken together, our study demonstrated a critical function of circARHGAP12 on OS chemotherapy resistance and energy metabolism abnormality, providing critical roles on OS treatment.

A1BG-AS1 promotes the biological functions of osteosarcoma cells via regulating the microRNA-148a-3p/USP22 axis and stabilizing the expression of SIRT1 through deubiquitinase function

ABSTRACT Background The study aims to explore the role of A1BG antisense RNA 1 (A1BG-AS1), microRNA (miR)-148a-3p and ubiquitin-specific protease 22 (USP22) on osteosarcoma (OS) cell growth. Research design & methods A1BG-AS1, miR-148a-3p, USP22, and silent information regulator 2 homolog 1 (SIRT1) levels in OS tissues and cells were determined. The effects of A1BG-AS1, miR-148a-3p, and USP22 on the biological functions of OS cells were examined by functional assays. In vivo assay was conducted to observe the effect of A1BG-AS1 on OS growth in vitro. The relationship of A1BG-AS1, miR-148a-3p, and USP22 was analyzed by bioinformatics analysis, RNA-fluorescence in situ hybridization, luciferase activity, and RNA binding protein immunoprecipitation assays. The relation between USP22 and SIRT1 was evaluated by immunoprecipitation. Results A1BG-AS1 and USP22 were highly expressed, and miR-148a-3p was lowly expressed in OS tissues and cells. Down-regulation of A1BG-AS1 and USP22 or up-regulation of miR-148a-3p impaired the malignant behaviors of OS cells. A1BG-AS1 sponged miR-148a-3p, and miR-148a-3p targeted USP22, thereby inhibiting USP22 expression. Up-regulating USP22 reversed the A1BG-AS1 suppression-induced phenotypic inhibition of OS cells. USP22 affected the biological functions of OS cells by deubiquitinating SIRT1. Conclusion A1BG-AS1 facilitates the biological functions of OS cells via mediating the miR-148a-3p/USP22 axis.

Identification of optimal reference genes for gene expression normalization in human osteosarcoma cell lines under proliferative conditions.

The molecular pathogenesis and therapeutic target research studies on osteosarcoma (OS) have developed well during the last few years using various OS cell lines with reverse transcription quantitative polymerase chain reaction (RT-qPCR). However, the identification of suitable reference genes of RT-qPCR for OS cell lines has not been reported. Here, we conducted the normalization research of 12 reference genes (GAPDH, ACTB, 18S, B2M, ALAS1, GUSB, HPRT1, HMBS, PPIA, PUM1, RPL29, and TBP) for gene expression analysis in four kinds of human OS cell lines (U2OS, Saos-2, HOS, and MG-63) to improve the investigation of molecular mechanisms and the accuracy of diagnosis and prognostic molecular targets of OS. The gene expression stability and applicability of the 12 reference gene candidates were determined using geNorm, NormFinder, and BestKeeper software. The results indicated that PUM1 and the combination of PPIA + ALAS1 were recommended as the optimal reference gene in these four different sources of human OS cell lines under proliferative conditions. The present study identified the most suitable reference genes and reference gene combinations for OS cell lines under proliferative conditions in order to use in gene expression profile analysis. A reliable standardized method has the potential to improve the understanding of the biological mechanisms underlying OS in the future.

Dioscin suppresses proliferation and metastasis of osteosarcoma by inhibiting HuR/Pim1 axis via the induction of miR-16-5p level

DS suppressed the growth of solid tumor and inhibited HuR/Pim1 in mice model in a miR-16-5p induction-dependent manner. • DS suppresses proliferation and metastasis of osteosarcoma. • The anti-OS function of DS is associated with the function of miRs. • MiR-16-5p plays an indispensable role in the anti-OS function of DS. Dioscin (DS) is a natural compound with inhibitory effects on multiple cancer types and we explored the mechanism driving the antagonizing effect of DS on osteosarcoma (OS). OS cell lines were treated with DS and microRNAs (miRs) responding to DS treatment were determined. Effects of DS on viability, apoptosis, metastasis, and miR-16-5p/HuR/Pim1 pathway activity were assessed. MiR-16-5p was inhibited before DS treatment to confirm its central role in anti-OS effects of DS. The conclusion derived from in vitro assays was verified with a mouse model. DS suppressed viability, invasion and migration, while induced apoptosis in OS cells. Moreover, the compound also induced the expression of miR-16-5p, contributing to the inhibition of HuR/Pim1 pathway. The inhibited expression of miR-16-5p counteracted the anti-OS function of DS, which was also validated in mice. Anti-OS effects of DS depended on the induction of miR-16-5p, making the compound a promising adjuvant agent for treating OS.

Long non-coding RNA ERVK13-1 aggravates osteosarcoma through the involvement of microRNA-873-5p/KLF5 axis.

To explore the effect and mechanism of long noncoding RNA ERVK13-1 on osteosarcoma (OS) cell development by regulation of miR-873-5p/KLF5 axis. The expression of ERVK13-1 in the collected tissue was detected by RT-qPCR, and then the relationship between ERVK13-1 expression and clinical characteristics of OS patients was analyzed. After OS cell lines were transfected with miR-873-5p inhibitor, si-ERVK13-1, si-KLF5 or their negative controls, the expression of ERVK13-1, miR-873-5p, and KLF5 in OS cell lines were measured, followed by determination of their effects on cell proliferation, migration, and invasion abilities. Moreover, the binding relationships of ERVK13-1 and miR-873-5p, as well as miR-873-5p and KLF5, were verified by the dual-luciferase reporter gene assay. Highly expressed ERVK13-1 was found in OS tissues, which was closely related to tumor size, tumor node metastasis, and distant metastasis. The overall survival of OS patients with high expression of ERVK13-1 was poorer than those with low expression of ERVK13-1. Elevated ERVK13-1 and KLF5 but suppressed miR-873-5p was observed in the OS cell lines U2OS and MG63. Transfection with miR-873-5p inhibitor enhanced the malignant potentials of OS cells, and transfection with si-ERVK13-1 or si-KLF5 reduced these abilities of OS cells. ERVK13-1 bound to miR-873-5p and KLF5 was a target gene of miR-873-5p. The ERVK13-1/miR-873-5p/KLF5 axis confers vital effect on the occurrence and progression of OS, thus providing possible guidance for the clinical treatment of OS.

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

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

Geiparvarin Inhibits OS Metastasis through Upregulation of ANGPTL4 Expression by Inhibiting miRNA-3912-3p Expression.

Background Geiparvarin (GN) is a natural compound with anticancer activity. However, the effect of GN on osteosarcoma (OS) and the anticancer mechanism of GN are still unclear. Methods Cell viability was measured by MTT assay. Invasion and migration were measured by transwell assay. The miRNAs, genes, and signaling pathways affected by GN were confirmed by whole-genome sequencing and bioinformatics analysis. The expression level of mRNA and protein was measured by qRT-PCR and western blot. Animal experiment was performed for confirming the GN anticancer effect and side effect in vivo. Results Our results show that GN significantly inhibits OS cell growth and metastasis in vitro. In vivo experiment also showed that GN dramatically suppressed OS lung metastasis and no side effects were found. GN treatment inhibited OS metastasis through upregulating the ANGPTL4 expression. In addition, GN inhibited the expression of miR-3912-3p, which targets ANGPTL4. Conclusion Our data clearly indicate that GN is a candidate drug for OS treatment, and GN plays its role through miR-3912-3p/ANGPTL4 in OS.

Unveiling osteosarcoma responses to DAPT combined with cisplatin by using confocal Raman microscopy.

The aim of this study was to clarify the dose- and time-dependent effect of the γ-secretase inhibitor (DAPT) combined with cisplatin on osteosarcoma (OS) cells, evaluated by confocal Raman microspectral imaging (CRMI) technology. The intracellular composition significantly changed after combined drug action compared with the sole cisplatin treatment, proving the synergistic effect of DAPT combined with cisplatin on OS cells. The principal component analysis-linear discriminant analysis revealed the main compositional variations by distinguishing spectral characteristics. K-means cluster and univariate imaging were used to visualize the changes in subcellular morphology and biochemical distribution. The results showed that the increase of the DAPT dose and cisplatin treatment time in the combination treatment induced the division of the nucleus in OS cells, and other organelles also showed significant physiological changes compared with the effect of sole cisplatin treatment. After understanding the cellular response to the combined drug treatment at a molecular level, the achieved results provide an experimental fact for developing suitable individualized tumor treatment protocols.

Long-non-coding RNA RUSC1-AS1 accelerates osteosarcoma development by miR-101-3p-mediated Notch1 signalling pathway

BackgroundLong non-coding RNA (lncRNA) RUSC1-AS1 has been found to modulate several cancers development. In this study, we explored the role of RUSC1-AS1 on osteosarcoma (OS) progression. MethodsQuantitative Real-time PCR (qRT-PCR) was conducted to test the relative expression of RUSC1-AS1, Notch1 mRNA and miR-101-3p in OS tissues and adjacent normal tissues. Gain- or loss- of functional assays were carried out to determine the roles of RUSC1-AS1 and miR-101-3p in OS progression both in vitro and in vivo. The expression of E-cadherin, N-cadherin, Vimentin, Snail, Notch1, Ras and ERK was determined by Western blot. Furthermore, the relationships between RUSC1-AS1 and miR-101-3p, Notch1 and miR-101-3p were confirmed through RNA immunoprecipitation (RIP) and dual luciferase reporter gene assay. ResultsRUSC1-AS1 and Notch1 were up-regulated in OS cells and tissues. Down-regulating RUSC1-AS1 significantly attenuated the proliferative, epithelial-mesenchymal transition (EMT), growth, lung metastasis, migrative and invasive abilities of MG-63 and Saos-2 cells, and aggravated apoptosis, accompanied with down-regulated Notch1-Ras-ERK1/2 in those cells both in vitro and in vivo, while overexpression of RUSC1-AS1 exerted opposite effects. Overexpressing miR-101-3p in OS cells had similar effects as RUSC1-AS1 inhibition. In addition, RUSC1-AS1 functioned as a competing endogenous RNA (ceRNA) to competitively sponge miR-101-3p, thus upregulating Notch1 expression and mediating the malignant behaviors of OS cells. ConclusionRUSC1-AS1 is a novel oncogenic lncRNA in OS through the miR-101-3p-Notch1-Ras-ERK pathway, which might be a potential therapeutic target for OS.

Association of RDM1 with osteosarcoma progression via cell cycle and MEK/ERK signalling pathway regulation.

RAD52 motif‐containing 1 (RDM1), a key regulator of DNA double‐strand break repair and recombination, has been reported to play an important role in the development of various human cancers, such as papillary thyroid carcinoma, neuroblastoma and lung cancer. However, the effect of RDM1 on osteosarcoma (OS) progression remains unclear. Here, this study mainly explored the connection between RDM1 and OS progression, as well as the underlying mechanism. It was found that RDM1 was highly expressed in OS cells compared with human osteoblast cells. Knockdown of RDM1 caused OS cell proliferation inhibition, cell apoptosis promotion and cell cycle arrest at G1 stage, whereas RDM1 overexpression resulted in the opposite phenotypes. Furthermore, RDM1 silencing leads to a significant decrease in tumour growth in xenograft mouse model. RDM1 also increased the protein levels of MEK 1/2 and ERK 1/2. All these findings suggest that RDM1 plays an oncogenic role in OS via stimulating cell cycle transition from G1 to S stage, and regulating MEK/ERK signalling pathway, providing a promising therapeutic factor for the treatment of OS.

PLEK2 promotes osteosarcoma tumorigenesis and metastasis by activating the PI3K/AKT signaling pathway.

Increasing evidence suggest that pleckstrin-2 (PLEK2) acts as an oncogene in several malignancies. The present study aimed to investigate the effects of PLEK2 on osteosarcoma (OS) tumorigenesis and metastasis. PLEK2 expression in OS was analyzed via bioinformatics, reverse transcription-quantitative PCR, western blot and immunohistochemistry analyses. The Cell Counting Kit-8 (CCK-8), colony formation and EdU assays were performed to assess the role of PLEK2 in OS cell proliferation. The pro-metastatic effects of PLEK2 were assessed via the Transwell and wound healing assays. In addition, the PLEK2 downstream pathway was analyzed via bioinformatics analysis and verified via western blot analysis. The results demonstrated that PLEK2 expression was upregulated in both OS cell lines and specimens. The results of the CCK-8, colony formation and EdU assays demonstrated that PLEK2 promoted OS cell proliferation in vitro. The in vivo experiments further demonstrated that PLEK2 knockdown significantly suppressed OS growth. In addition, the Transwell and wound healing assays indicated that PLEK2 promoted OS invasiveness in vitro, which was induced by the activation of the epithelial-to-mesenchymal transition process. Bioinformatics analysis revealed that PLEK2 can activate the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mechanistic target of rapamycin (mTOR) pathway, which was verified via western blot analysis. Taken together, the results of the present study suggest that PLEK2 may play a tumor-promoting role in OS via the PI3K/AKT signaling pathway.

Sauchinone inhibits hypoxia-induced invasion and epithelial–mesenchymal transition in osteosarcoma cells via inactivation of the sonic hedgehog pathway

Hypoxia is a typical feature of solid tumors and is closely associated with tumor progression. Sauchinone, a biologically diastereomeric lignan, is isolated from the root of Saururus chinensis and has been widely used for the treatment of various diseases. Recently, sauchinone has been reported to play an anti-cancer role in cancer development under normoxia or hypoxia. However, the specific effects of sauchinone on osteosarcoma (OS) remain unclear. The aim of the present study was to investigate the role of sauchinone in OS progression under hypoxic conditions. The human OS cell lines U2OS and MG-63 were exposed to hypoxia followed by treatment with sauchinone. Cell viability was assessed by the CCK-8 assay. Cell migration and invasion were detected by transwell assays. The expression levels of VEGF, HIF-1α, E-cadherin and N-cadherin were examined by the western blot analysis. Our study showed that OS cell migration and invasion were significantly enhanced by hypoxia. Besides, hypoxic conditions resulted in a remarkable change in the expression of EMT markers. All these effects induced by hypoxia were abrogated by sauchinone treatment. Moreover, sauchinone inhibited hypoxia-induced activation of the sonic hedgehog (Shh) pathway. Additionally, the Shh agonist reversed the inhibitory effect of sauchinone on hypoxia-induced invasion and EMT of OS cells. In conclusion, these findings demonstrated that sauchinone inhibits hypoxia-induced invasion and EMT in OS cells via inactivation of the Shh pathway. We provided a novel insight for understanding the mechanisms underlying the anti-cancer effect of sauchinone and suggested sauchinone as a promising agent for OS treatment.

Parathyroid hormone type 1 receptor regulates osteosarcoma K7M2 Cell growth by interacting with angiotensinogen.

This study aimed to determine the interactions between parathyroid hormone type 1 receptor (PTHR1) and angiotensinogen (AGT) and the effects of these agents on osteosarcoma (OS). We constructed a stably transfected mouse OS K7M2 cell line (shPTHR1‐ K7M2) using shRNA and knocked down AGT in these cells using siRNA‐AGT. The transfection efficiency and expression of AGT, chemokine C‐C motif receptor 3 (CCR3), and chemokine (C‐C motif) ligand 9 (CCL9) were determined using real‐time quantitative PCR. Cell viability and colony formation were assessed using Cell Counting Kit‐8 and crystal violet staining, respectively. Cell apoptosis and cycle phases were assessed by flow cytometry, and cell migration and invasion were evaluated using Transwell assays. Interference with PTHR1 upregulated the expression of AGT and CCR3, and downregulated that of CCL9, which was further downregulated by AGT knockdown. Cell viability, migration, invasion and colony formation were significantly decreased, while cell apoptosis was significantly increased in shPTHR1‐K7M2, compared with those in K7M2 cells (P < .05 for all). However, AGT knockdown further inhibited cell viability after 72 h of culture but promoted cell migration and invasion. PTHR1 interference decreased and increased the numbers of cells in the G0/G1 and G2/M phases, respectively, compared with those in K7M2 cells. Angiotensinogen knockdown increased the number of cells in the G0/G1 phase compared with that in the shPTHR1‐K7M2 cells. Therefore, PTHR1 affects cell viability, apoptosis, migration, invasion and colony formation, possibly by regulating AGT/CCL9 in OS cells.

LINC01278 is Highly Expressed in Osteosarcoma and Participates in the Development of Tumors by Mediating the miR-134-5p/KRAS Axis.

PurposeThere is increasing evidence that non-coding RNAs (ncRNAs), including long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), produce a critical regulatory effect on osteosarcoma (OS). LINC01278, as a newly discovered lncRNA, is found to be highly expressed in OS, but its related mechanism remains unclear. This research, therefore, is designed to study the mechanism of LINC01278 in OS and to find potential targets for clinical use.MethodsqRT-PCR was applied to determine the relative expression of LINC01278 and analyze its diagnostic value in OS. CCK-8, Transwell and flow cytometry were utilized for the determination of cell proliferation, migration/invasion, and apoptosis. RIP and RNA pull-down experiments were used to verify the targeted binding effect of miR-134-5p and LINC01278. The relationship between miR-134-5p and LINC01278 or KRAS was analyzed using dual luciferase reporter gene. The effects of LINC01278 on tumor growth in nude mice was analyzed by in vivo experiment.ResultsqRT-PCR showed that LINC01278 increased in OS tissues and serum, indicating poor prognosis. In addition, LINC01278 was also of high value for OS diagnosis. Functional experiments showed that LINC01278 inhibited KRAS-mediated OS cell proliferation and metastasis through miR-134-5p. Finally, the results of an in vivo animal model indicated that LINC01278 promoted OS growth.ConclusionLINC01278 is expressed highly in OS, and patients with high LINC01278 expression have poor prognosis. Moreover, LINC01278 can suppress the proliferation and apoptosis of OS cells through mediating miR-134-5p/KRAS axis, which is expected to become a potential therapeutic target for OS.

MiR-582-5p inhibits the growth and invasion of osteosarcoma cell by targeting NOVA1.

To investigate the role of microRNA-582-5p (miR-582-5p) on osteosarcoma (OS) cell behaviors and provide potential therapeutic targets for OS. Expression levels of miR-582-5p in OS cell lines and normal cell lines were measured by quantitative real-time PCR. Cell proliferation, migration and invasion capacities were assessed by cell counting kit-8 assay, wound-healing assay, and transwell invasion assay, respectively. Downstream target of miR-582-5p was confirmed by Luciferase activity reporter assay and Western blotting assay. MiR-582-5p expression was downregulated in OS cell lines compared with normal cell lines. Overexpression of miR-582-5p inhibits OS cell proliferation, migration, and invasion capacities. Neuro-oncological ventral antigen 1 (NOVA1) was chosen as target gene of miR-582-5p by bioinformatics analysis and Luciferase reporter assay. Moreover, overexpression of NOVA1 could impair tumor suppression role of miR-582-5p on OS cell behaviors. MiR-582-5p exerts tumor-suppressive role on OS cell behaviors via targeting NOVA1 in vitro, which will help us to understand the mechanisms underlying OS progression.

Ginsenoside Rh2 impedes proliferation and migration and induces apoptosis by regulating NF-κB, MAPK, and PI3K/Akt/mTOR signaling pathways in osteosarcoma cells.

Ginsenoside Rh2 is a primary bioactive compound obtained from ginseng that indicated anticancer activities against several malignant tumors. However, previous studies have reported little about the inhibitory effect of Rh2 on osteosarcoma (OS). This study aims to explore whether Rh2 could exert anticancer effects in OS cells and further investigate the proliferation, migration, and apoptosis mechanisms induced by Rh2 in human OS U20S cell line. The viability of U20S cells was obtained by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide assay. Cell migration property was analyzed by wound-healing assay. Apoptosis was visualized using terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL), 4',6-diamidino-2-phenylindole (DAPI), and annexin V/propidium iodide (PI) staining. Relative protein expressed was confirmed through Western blot analysis. Mitochondrial membrane potential was evaluated by JC-1 staining. In this study, we used broad-spectrum anticancer drug cisplatin (CP) as a positive control. The results indicated that Rh2 remarkably inhibited cell viability of U20S cells in a dose- and time-dependent manner, and suppressed migration. TUNEL, DAPI, annexin V/PI, and JC-1 assay suggested that Rh2 could induce cellular apoptosis. Rh2 could reduce the levels of Bcl-2, caspase 3, and caspase 9, and promote the expression level of Bax in U20S cells. Moreover, Rh2 could induce apoptosis by promoting mitogen-activated protein kinase (MAPK) signaling pathway and inhibit PI3K/Akt/mTOR and nuclear factor-κB (NF-κB) signaling pathway in U20S cells. These findings indicated that Rh2 has an anticancer effect on U20S cells by regulating MAPK, PI3K/Akt/mTOR, and NF-κB signaling pathway.

PENK inhibits osteosarcoma cell migration by activating the PI3K/Akt signaling pathway

BackgroundThis article reports the effects of proenkephalin (PENK) on osteosarcoma (OS) cell migration.MethodsA Gene Expression Omnibus (GEO) dataset was used to identify differentially expressed genes (DEGs) in OS tumor samples and normal human osteoblasts. Tumor tissue and adjacent normal tissue were collected from 40 OS patients. MG63 cells were transfected with si-PENK. Transwell migration assays and wound healing assays were performed to compare the effect of PENK on migration. Moreover, LY294002 was used to identify the potential mechanism. Gene expression was examined via qRT-PCR and Western blotting.ResultsBioinformatic analysis revealed that PENK was downregulated in OS tumor samples compared with normal human osteoblasts. Moreover, PENK was identified as the hub gene of the DEGs. The PI3K/Akt signaling pathway was significantly enriched in the DEGs. Moreover, PENK was downregulated in OS and MG63 cells compared with the corresponding control cells. Silencing PENK promoted MG63 cell migration; however, treatment with LY294002 partially attenuated PENK silencing-induced OS cell migration.ConclusionPENK inhibits OS cell migration by activating the PI3K/Akt signaling pathway.