Humans ; Osteosarcoma ; metabolism ; Signal Transduction ; physiology ; TOR Serine-Threonine Kinases ; metabolism

OBJECTIVETo detect the expression of CXCL14 in human osteosarcoma cell lines and tissues and investigate its association with the prognosis of the patients.

METHODSRT-PCR, enzyme-linked immunosorbent assay (ELISA) and real-time PCR were used to detect the expression of CXCL14 in 4 osteosarcoma cell lines and in 40 pairs of osteosarcoma tissues and adjacent muscular tissues. CCK8 assay and colony formation assay was used to assess the effect of CXCL14 suppression mediated by two specific siRNAs on the proliferation of U2OS osteosarcoma cells. Immunohistochemistry was performed to detect the expression of CXCL14 in 58 osteosarcoma tissues, and Kaplan-Meier method and log-rank test were performed for survival analysis of the patients.

RESULTSSignificant up-regulation of CXCL14 expression was found in the osteosarcoma cell lines and in osteosarcoma tissues compared with the adjacent muscles (P<0.01). In U2OS cell, suppression of CXCL14 expression by siRNA significantly inhibited the cell proliferation (P<0.01) and colony formation rate (P<0.05). Kaplan-Meier survival analysis indicated that patients with high CXCL14 expression had worse prognosis than those with low CXCL14 expression (P=0.02).

CONCLUSIONCXCL14 is up-regulated in both osteosarcoma cell lines and primary osteosarcoma tissues to promote the proliferation of osteosarcoma cells. A high CXCL14 expression in osteosarcoma tissues is associated with a poor prognosis, suggesting the that CXCL14 serve as a potential therapeutic target for osteosarcoma.

Bone Neoplasms ; metabolism ; pathology ; Cell Line, Tumor ; Cell Proliferation ; Chemokines, CXC ; metabolism ; Humans ; Osteosarcoma ; metabolism ; pathology ; Prognosis

BACKGROUND: Doxorubicin has proved to be a useful chemotherapeutic agent especially for osteogenic sarcoma. It induces cancer cell death via apoptosis. MATERIALS AND METHODS: To explore and analyze the changes of gene expression during doxorubicin induced apoptosis on human osteogenic sarcoma, Saos-2 cell, cDNA microarray was performed. After treatment with doxorubicin, total RNA was purified and expressed genes were investigated with a 17k human cDNA microarray. RESULTS: For analysis of the cDNA microarray, the genes were filtered using the sum of the median value of Cy3 and Cy5 signal intensity of greater than 800. Expression of 264 genes was changed by more than 2 fold, and the expression of 35 genes was changed more than 3 fold after treatment with doxorubicin. The genes were primarily related to cell death, cell growth and maintenance, signal transduction, cellular component, transport, and metabolism. CONCLUSION: Treatment with doxorubicin induced expressional change of many genes. Some of the genes might be related with apoptosis directly or indirectly. Further study is now needed to characterize these genes.
Apoptosis* ; Cell Death ; Doxorubicin* ; Gene Expression* ; Humans ; Metabolism ; Oligonucleotide Array Sequence Analysis ; Osteosarcoma ; RNA ; Signal Transduction

BACKGROUND: Methotrexate (MTX), one of the main drugs used to treat osteosarcoma, is a representative folic acid antagonist. Polymorphisms of various enzymes involved in the metabolism of MTX could contribute to differences in response to MTX in pediatric osteosarcoma patients. METHODS: Blood and tissue samples were obtained from 37 pediatric osteosarcoma patients who were treated with high-dose MTX therapy. The following 4 single nucleotide polymorphisms (SNPs) were analyzed: ATIC 347C>G, MTHFR 677C>T, MTHFR 1298A>C and SLC19A1 80G>A. Serial plasma MTX concentrations after high-dose MTX therapy and MTX-induced toxicities were evaluated. Correlations among polymorphisms, MTX concentrations and treatment-induced toxicities were assessed. RESULTS: Plasma MTX levels at 48 hours after high-dose MTX infusion were significantly associated with SLC19A1 80G>A (P=0.031). Higher plasma levels of MTX at 48 and 72 hours were significantly associated with MTX-induced mucositis (P=0.007 and P=0.046) and renal toxicity (P=0.002), respectively. SNP of SLC19A1 gene was associated with development of severe mucositis (P=0.026). CONCLUSION: This study suggests that plasma levels of MTX are associated with GI and renal toxicities after high-dose MTX therapy, and genetic polymorphisms that affect the metabolism of MTX may influence drug concentrations and development of significant side effects in pediatric patients treated with high-dose MTX.
Folic Acid* ; Humans ; Metabolism ; Methotrexate* ; Mucositis ; Osteosarcoma* ; Plasma ; Polymorphism, Genetic* ; Polymorphism, Single Nucleotide

OBJECTIVEOsteosarcoma is the most common type of malignant bone tumor in children and adolescents. The role of E3 ligases in tumorigenesis is currently a focus in tumor research. In the present study, we investigated the role of the E3 ligase tripartite motif 21 (TRIM21) in osteosarcoma cell proliferation.

METHODS3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assays were used to assess osteosarcoma cell viability. U2-OS cells stably carrying a recombinant lentivirus expressing tetracycline-regulated TRIM21 were screened. Co-immunoprecipitation was coupled with LCMS/MS analysis to identify novel interacting partners of TRIM21. Co-immunoprecipitation and bimolecular fluorescence complementation (BIFC) were performed to validate the interactions between TRIM21 and its novel partner YWHAZ. A TRIM21-ΔRING construct was generated to test the effects of TRIM21 ligase activity on YWHAZ.

RESULTSTRIM21 positively regulated osteosarcoma cell proliferation. Overexpression of TRIM21 enhanced osteosarcoma cell tolerance toward various stresses. YWHAZ protein was identified as a novel interacting partner of TRIM21 and its expression levels were negatively regulated by TRIM21. The RING domain of TRIM21 was required for TRIM21 negative regulation of YWHAZ expression. However, overexpression of YWHAZ did not affect positive regulation of osteosarcoma cell proliferation by TRIM21.

CONCLUSIONOur results further clarify the molecular mechanisms underlying the pathogenesis of osteosarcoma.

14-3-3 Proteins ; genetics ; metabolism ; Cell Proliferation ; genetics ; Humans ; Osteosarcoma ; genetics ; Ribonucleoproteins ; genetics ; metabolism ; Tumor Cells, Cultured

12E7 Antigen ; Antigens, CD ; metabolism ; Cell Adhesion Molecules ; metabolism ; Diagnosis, Differential ; Humans ; Kidney Neoplasms ; metabolism ; pathology ; surgery ; Male ; Middle Aged ; Nephrectomy ; Osteosarcoma ; metabolism ; pathology ; surgery ; Vimentin ; metabolism

OBJECTIVE: To observe the effect of different concentrations of nylestriol (NYL) and levonorgestrel (LNG) on the expression of ERα and ERβ in human osteoscarcoma MG-63 cell lines, and to explore the impact of paracrine effect on the gene expression. METHODS: MG-63 cells were treated with 3 concentrations (10(-10),10(-8), and 10(-6) mol/L) of NYL or LNG. The untreated control group and the positive control group were also established. The 2 groups treated with NYL (10(-10) mol/L) or LNG (10(-8) mol/L) were designed to renew the medium every 12 h. Semi-quantitative RT-PCR was conducted to detect the mRNA expression of ERα and ERβ on the MG-63 cells treated with different concentrations of the 2 drugs, respectively. RESULTS: Both drugs up-regulated ERα and ERβ mRNA expression. The best concentration for both NYL and LNG was 10(-6) mol/L for ERα expression. As for ERβ, the best concentration of NYL and LNG was 10(-10) mol/L and 10(-8) mol/L. The role of medium replacement on the expression of ERα was not observed, but medium replacement inhibited ERβ expression. CONCLUSION Both NYL and LNG can up-regulate the mRNA expression of ER subtypes in MG-63 cells, with mutual restriction between the 2 subtypes. The paracrine effect on MG-63 cell lines may be involved in the regulation process of mRNA expression of ERβ.
Cell Line, Tumor ; Estrogen Receptor alpha ; genetics ; metabolism ; Estrogen Receptor beta ; genetics ; metabolism ; Humans ; Levonorgestrel ; pharmacology ; Osteosarcoma ; metabolism ; pathology ; Quinestrol ; analogs & derivatives ; pharmacology ; RNA, Messenger ; genetics ; metabolism

To compare the expression level of metastasis associated-1 (MTA1) gene in high and low metastatic human osteosarcoma cell lines and examine the relationship of MTA1 expression and the metastasis potentiality of osteosarcoma cells, the expression of MTA1 in MG-63 osteosarcoma cell lines with high and low metastasis potential was detected by semiquantitative TR-PCR. Boyden chamber invasion assay was used to evaluate the invasive capacity in vitro in two osteosarcoma cell lines. The low metastasis MG-63 cells were transfected with MTA1 full-length cDNA expression plasmid by lipofectamine and the changes of MTA1 expression and in vitro invasion potential were examined after the transfection. Our results showed that MG63 cell line with high metastasis potential expressed significantly higher MTA1 than that of MG63 cells with low metastasis as reavealed by RT-PCR. The invasion potential of low metastasis MG63 cell line was increased after MTA1 gene transfection. It is concluded that there may be a relationship between MTA 1 and invasive potentiality of human osteosarcoma cells, and the mechanism of MTA1 in osteosarcoma metastasis and its possible role in associated gene therapy deserve further study.
Bone Neoplasms/*metabolism ; Bone Neoplasms/pathology ; Gene Expression Regulation, Neoplastic ; Histone Deacetylases/*biosynthesis ; Histone Deacetylases/genetics ; Neoplasm Invasiveness ; Neoplasm Metastasis ; Osteosarcoma/*metabolism ; Osteosarcoma/pathology ; RNA, Messenger/biosynthesis ; RNA, Messenger/genetics ; Repressor Proteins/*biosynthesis ; Repressor Proteins/genetics ; Tumor Cells, Cultured

To investigate the effect of miR-30a/HMGA2-mediated autophagy in osteosarcoma cells on apoptosis induced by chemotherapeutics. 
 Methods: A total of 30 osteosarcoma tissues of sensitive and resistant to chemotherapeutics were divided into a chemotherapy-sensitive group and a chemotherapy-resistant group. The mRNA expression levels of miR-30a and high mobility group protein A2 (HMGA2) in the chemotherapy-sensitive group and the chemotherapy-resistant group, and the mRNA expression levels of miR-30a in osteosarcoma U2-OS cells treated by cisplatin, doxorubicin and methotrexate at different concentrations were detected by real-time PCR. The expression levels of autophagy related protein Beclin 1, microtubule associated protein 1 light chain 3B (LC3B) and autophagy factor P62 were detected by Western blotting. The osteosarcoma U2-OS cells were transfected with miR-30a mimics and miR-30a inhibitors to construct a miR-30a high expression group, a miR-30a low expression group and a control group. The expression levels of Beclin 1, LC3B and P62 in osteosarcoma U2-OS cells after treatment of cisplatin and doxorubicin in these 3 groups were detected by Western blotting; the level of autophagy was detected by monodansylcada (MDC) staining; the level of ROS was detected by dihydroethidium (DHE); the level of cell surviving rate was detected by cell counting kit-8 (CCK-8); the level of apoptosis was detected by annexin APC/PI double staining; the level of mitochondria oxidative damage was detected by mitochondrial membrane potential assay kit with JC-1 (JC-1 method). The interaction between miR-30a and HMGA2 was detected by dual luciferase reporter assay. The osteosarcoma U2-OS cells were transfected with HMGA2 mimics and HMGA2-shRNA to construct a high HMGA2 group, a low HMGA2 group, and a control group. The expression levels of Beclin 1, LC3B and P62 in osteosarcoma U2-OS cells after the treatment of cisplatin were detected by Western blotting.
 Results: The level of miR-30a in the chemotherapy-resistant tissues was significantly lower than that in the chemotherapy-sensitive tissues (P<0.05), and the expression of HMGA2 was opposite comparing to that of miR-30a (P<0.05). After the treatment by low concentration (5 μmol/L) of chemotherapeutics, the level of miR-30a was down-regulated in osteosarcoma U2-OS cells, accompanied with up-regulation of Beclin 1 and LC3B (P<0.01) and down-regulation of P62 (P<0.01). Compared with the control group, the expression levels of Beclin 1 and LC3B were significantly decreased (P<0.05), and the expression level of P62 was significantly increased (P<0.05) in the miR-30a high expression group, which was opposite in the miR-30a low expression group. In the miR-30a high expression group treated by chemotherapeutics, the level of autophagy and the cell survival rate were lower than those in group with low expression of miR-30a, while the levels of ROS, the mitochondrial oxidative damage and the apoptosis were higher than those in group with low expression of miR-30a (all P<0.05). The targeting interaction between HMGA2 and miR-30a were verified by dual luciferase reporter assay. Compared with the control group, the expression levels of Beclin 1 and LC3B were significantly increased (P<0.05), and the expression level of P62 was significantly decreased (P<0.05) in the HMGA2 high expression group, which was opposite in the HMGA2 low expression group.
 Conclusion: Suppression of miR-30a/HMGA2-mediated autophagy in osteosarcoma cells is likely to enhance the therapeutic effect of chemotherapeutics.
Apoptosis ; Apoptosis Regulatory Proteins ; Autophagy ; Beclin-1 ; Bone Neoplasms ; Cell Line, Tumor ; HMGA2 Protein ; metabolism ; Humans ; MicroRNAs ; genetics ; Osteosarcoma

OBJECTIVE: To investigate the prognostic value and mechanism of long non-coding RNA DLEU1(LncRNA DLEU1) in osteosarcoma. METHODS: The tissue samples and clinical data of 86 patients with osteosarcoma treated by orthopaedic surgery in our hospital from January 2012 to December 2014 were retrospectively collected. The expression of LncRNA DLEU1 in pathological tissues was detected by qRT-PCR, then the patients were divided into high and low expression of LncRNA DLEU1 groups. Osteosarcoma cell line HOS was divided into two groups, down-regulated expression group (si-DLEU1 group) and negative control group (si-NC group). LncRNA DLEU1 siRNA and negative control sequence were transfected by Lipofectamine 3000. Chi-square test was used to analyze the relationship between the expression of LncRNA DLEU1 and the clinicopathological factors of osteosarcoma. Kaplan-Meier method was used to compare the difference of the overall survival rate of osteosarcoma patients between the high and low expression groups of LncRNA DLEU1. The risk factors affecting the overall survival rate of osteosarcoma were analyzed by single factor and multifactor analysis. The number of invasive cells in the two groups was determined and compared by Transwell assay. RESULTS: The expression of LncRNA DLEU1 in osteosarcoma tissue was higher than that in adjacent tissues (P<0.001). The expression of LncRNA DLEU1 in human osteosarcoma cell lines (MG-63, U-2 OS, and HOS) was significantly higher than that in human osteoblast line hFOB 1.19 (P<0.001). The expression of LncRNA DLEU1 was significantly correlated with Enneking stage (P<0.001), distant metastasis (P=0.016), and histological grade (P=0.028). The 1-year overall survival rate of the LncRNA DLEU1 high expression group was significantly higher than that of the low expression group (90.7% vs 60.5%, P<0.001). The 5-year overall survival rate of the LncRNA DLEU1 high expression group was significantly higher than that of the low expression group (32.6% vs 11.6%, P<0.001). Univariate analysis showed that Enneking stage (P<0.001), tumor size (P=0.043), distant metastasis (P<0.001), histological grade (P<0.001), and expression of LncRNA DLEU1 (P<0.001) were risk factors for overall survival of osteosarcoma patients. Multivariate analysis showed that high expression of LncRNA DLEU1 [HR=1.948, 95% CI(1.141, 3.641), P=0.012] and distant metastasis[HR=4.108, 95% CI(2.169, 7.780), P<0.001] were independent risk factors for overall survival of osteosarcoma patients. The number of invasive cells in si-DLEU1 group was significantly lesser than that in si-NC group(139±13 vs 357±31, P<0.001). CONCLUSION High expression of LncRNA DLEU1 is a molecular marker affecting the prognosis of osteosarcoma patients. Downregulation of LncRNA DLEU1 can inhibit the invasion of osteosarcoma cells.
Humans ; Prognosis ; RNA, Long Noncoding/metabolism* ; Retrospective Studies ; Cell Proliferation/genetics* ; Cell Line, Tumor ; Osteosarcoma/genetics* ; Bone Neoplasms/pathology*