A20 inhibits the release of inflammatory cytokines by suppressing the activation of the nuclear factor-kappa B pathway in osteoarthritic fibroblast-like synoviocytes.

A growing number of studies suggest that synovitis plays an important role in the pathogenesis and progression of osteoarthritis (OA). As a negative mediator of the nuclear factor-kappa B (NF-κB) signaling pathway, the zinc finger protein A20 has significant anti-inflammatory properties. In this study, the differential expression of A20 was investigated at the mRNA and protein levels in human normal OA fibroblast-like synoviocytes (FLSs) and normal FLSs pretreated with TNF-α. We then measured the activation of the NF-κB pathway and expression of pro-inflammatory cytokines in the above three groups by western blotting, a human cytokine array and ELISA. We found that TNF-α activated the NF-κB pathway, increased the expression of the pro-inflammatory cytokines IL-6 and IL-8, and A20 expression in human normal FLSs. However, the role of A20 in FLSs was unclear. To clarify this, we investigated the effect of A20 overexpression in human normal FLSs. The results indicate that A20 inhibits the NF-κB signaling pathway activation and OA-associated pro-inflammatory cytokines release. The results of this study indicate that A20 has anti-inflammatory effects in FLSs, which makes it a potential target for OA synovitis treatment.

Proteomic profiling of osteosarcoma cells identifies ALDOA and SULT1A3 as negative survival markers of human osteosarcoma.

Osteosarcoma (OSA) is the most common primary malignancy of bone. Molecular mechanism underlying OSA remains to be fully elucidated. It is critical to identify reliable diagnostic and prognostic markers for OSA at the molecular levels. This study is designed to investigate possible molecular mechanisms behind OSA development and to identify novel prognostic markers related to OSA survival. We conduct a comprehensive proteomic profiling analysis of human OSA cell lines with differential metastatic potential. Through comprehensive combinatorial analyses of the proteomic data and the previously obtained cDNA microarray results, we identify 37 candidate proteins which are differentially expressed in OSA sublines. Among them, ALDOA and SULT1A3 are selected for further investigation. The expressions of protein are confirmed by Western blotting analysis. We further analyze the expression levels of ALDOA and SULT1A3 from 40 clinical cases of OSA. The results demonstrate that the expression of ALDOA and/or SULT1A3 is significantly higher in patients with worse survival time than patients with better survival time. Five-year survival analysis shows there is a statistically significant difference between two patient populations. The data strongly suggest that ALDOA and/or SULT1A3 expression level in biopsy samples may predict the clinical outcomes of OSA patients. Furthermore, the biological functions of ALDOA and SULT1A3 may be implicated in OSA development and/or progression.

Hydroxysafflor Yellow A protects spinal cords from ischemia/reperfusion injury in rabbits.

BACKGROUND: Hydroxysafflor Yellow A (HSYA), which is one of the most important active ingredients of the Chinese herb Carthamus tinctorius L, is widely used in the treatment of cerebrovascular and cardiovascular diseases. However, the potential protective effect of HSYA in spinal cord ischemia/reperfusion (I/R) injury is still unknown. METHODS: Thirty-nine rabbits were randomly divided into three groups: sham group, I/R group and HSYA group. All animals were sacrificed after neurological evaluation with modified Tarlov criteria at the 48th hour after reperfusion, and the spinal cord segments (L4-6) were harvested for histopathological examination, biochemical analysis and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) staining. RESULTS: Neurological outcomes in HSYA group were slightly improved compared with those in I/R group. Histopathological analysis revealed that HSYA treatment attenuated I/R induced necrosis in spinal cords. Similarly, alleviated oxidative stress was indicated by decreased malondialdehyde (MDA) level and increased superoxide dismutase (SOD) activity after HSYA treatment. Moreover, as seen from TUNEL results, HSYA also protected neurons from I/R-induced apoptosis in rabbits. CONCLUSIONS: These findings suggest that HSYA may protect spinal cords from I/R injury by alleviating oxidative stress and reducing neuronal apoptosis in rabbits.

Association between TGFBR1*6A and osteosarcoma: a Chinese case-control study.

BACKGROUND: TGFBR1*6A is a common hypomorphic variant of transforming growth factor beta receptor 1 (TGFBR1). TGFBR1*6A is associated with an increased cancer risk, but the association of this polymorphism with osteosarcoma remains unknown. We have measured the frequency of TGFBR1*6A variants in osteosarcoma cases and controls. METHODS: Our case-control study is based on 168 osteosarcoma patients and 168 age- and gender-matched controls. Blood samples were obtained and the TGFBR1*6A variant determined by PCR amplification and DNA sequencing. The odds ratio (OR) and 95% confidence interval (95% CI) for the TGFBR1*6A polymorphism were calculated by unconditional logistic regression, adjusted for both age and gender. Three models - dominant, additive and recessive - were used to analyze the contribution of the TGFBR1*6A variant to osteosarcoma susceptibility. RESULTS: Heterozygotic and homozygotic TGFBR1*6A variants represented 50.4% and 6.0% of the 168 cases, whereas the controls had 18. 5% and 1.3%, respectively. ORs for homozygosity and heterozygosity of the TGFBR1*6A allele were 4.6 [95% CI, 2.33-7.97] and 2.9 [95% CI, 1.59-5.34] in the additive model. There were significant increases in the TGFBR1*6A variants in osteosarcoma cases compared to control in all 3 models. Further analysis showed that TGFBR1*6A genotypes were not associated with gender, age, or tumor location. However, TGFBR1*6A was significantly associated with less metastasis. CONCLUSIONS: TGFBR1*6A, a dominant polymorphism of TGFBR1, is associated with increased susceptibility and metastasis spread of osteosarcoma.

Functional and radiological evaluations of unstable displaced proximal humeral fractures treated with closed reduction and percutaneous pinning fixation.

OBJECTIVE: The purpose of this study is to evaluate the functional and radiological outcomes of patients with unstable displaced proximal humeral fractures treated with closed reduction and percutaneous pinning (CRPP) fixation. METHODS: We retrospectively reviewed 87 cases of displaced (2-, 3- or 4-part fractures according to Neer classification) proximal humeral fractures treated with CRPP fixation in our center from September 2003 to September 2008. Sixty-four patients were followed up for a period ranging from 12 to 48 months (averaging 16.2 months) and evaluated for the functional and radiological outcomes by a series of standard questionnaire and measurement. RESULTS: The fractures in all 64 patients were healed with an average time of 15.4 weeks (ranging from 12 to 43 weeks), and the mean interval between the operation and full functional exercise was 17.3 weeks (ranging from 14 to 38 weeks). At the final follow-up visit, no patients showed shoulder instability; the mean range of abduction motion was 157.1° (ranging from 70 to 180°). For all patients, no statistically significant difference in the functional outcomes was observed between their 6-month and final follow-up visits, nor in the radiological findings between their immediately postoperative and fi- nal follow-up examinations. CONCLUSION: CRPP fixation is a feasible treatment option for unstable displaced proximal humeral fractures, especially for 2- and 3-part fractures in elderly patients. Although technically demanding, it offers reliable stability without extensive soft tissue dissection, allowing the early painless range of motion. This technique could also promote bone healing, prevent ischemic osteonecrosis of the head of humerus and lead to few complications.

A caspase-6 and anti-HER2 antibody chimeric tumor-targeted proapoptotic molecule decreased metastasis of human osteosarcoma.

Human growth factor receptor-2 (HER2), overexpressed as a result of gene amplification, is detected in 20-40% of patients with breast, ovarian, endometrial, gastric, bladder, prostate, or lung cancers, correlated to metastasis of many tumors, and considered to be a poor prognostic indicator for these tumors. However, the data was controversial for HER2 overexpression and the prognosis of osteosarcoma, which is the most common primary malignant bone tumor, presents a therapeutic challenge in medical oncology due to its metastasis and poor response to current treatments. Previously, we reported that the immunocasp-6 gene fused by a HER2-specific single-chain antibody with domain II of Pseudomonas exotoxin A (PEA) and the 5' end of the truncated active caspase-6 could selectively suppress the HER2-positive tumor growth. In this study, we extend its application. We first confirmed the higher HER2 expression on the surface of metastatic osteosarcoma SOSP-9607(E10) cells, which then be proved specifically addicted to immunocasp-6-induced cells killing in vitro. Thereafter, the efficacy of immunocasp-6 was tested in an osteosarcoma lung metastasis mouse model using intramuscular (i.m.) injections of liposome-encapsulated vectors. Our results showed that the expression of the immunocasp-6 gene not only significantly prolonged animal's survival, but also greatly inhibited tumor metastasis. Thereby, our strategy suggests an alternative approach to treating HER2/neu-positive osteosarcoma.

Establishment of reproducible osteosarcoma rat model using orthotopic implantation technique.

In experimental musculoskeletal oncology, there remains a need for animal models that can be used to assess the efficacy of new and innovative treatment methodologies for bone tumors. Rat plays a very important role in the bone field especially in the evaluation of metabolic bone diseases. The objective of this study was to develop a rat osteosarcoma model for evaluation of new surgical and molecular methods of treatment for extremity sarcoma. One hundred male SD rats weighing 125.45+/-8.19 g were divided into 5 groups and anesthetized intraperitoneally with 10% chloral hydrate. Orthotopic implantation models of rat osteosarcoma were performed by injecting directly into the SD rat femur with a needle for inoculation with SD tumor cells. In the first step of the experiment, 2x10(5) to 1x10(6) UMR106 cells in 50 microl were injected intraosseously into median or distal part of the femoral shaft and the tumor take rate was determined. The second stage consisted of determining tumor volume, correlating findings from ultrasound with findings from necropsia and determining time of survival. In the third stage, the orthotopically implanted tumors and lung nodules were resected entirely, sectioned, and then counter stained with hematoxylin and eosin for histopathologic evaluation. The tumor take rate was 100% for implants with 8x10(5) tumor cells or more, which was much less than the amount required for subcutaneous implantation, with a high lung metastasis rate of 93.0%. Ultrasound and necropsia findings matched closely (r=0.942; p<0.01), which demonstrated that Doppler ultrasonography is a convenient and reliable technique for measuring cancer at any stage. Tumor growth curve showed that orthotopically implanted tumors expanded vigorously with time-lapse, especially in the first 3 weeks. The median time of survival was 38 days and surgical mortality was 0%. The UMR106 cell line has strong carcinogenic capability and high lung metastasis frequency. The present rat osteosarcoma model was shown to be feasible: the take rate was high, surgical mortality was negligible and the procedure was simple to perform and easily reproduced. It may be a useful tool in the investigation of antiangiogenic and anticancer therapeutics. Ultrasound was found to be a highly accurate tool for tumor diagnosis, localization and measurement and may be recommended for monitoring tumor growth in this model.

Functional and radiological evaluations of high-energy tibial plateau fractures treated with double-buttress plate fixation.

OBJECTIVE: This study was designed to evaluate the functional and radiological outcomes of patients with complex tibial plateau fractures treated with double-buttress plate fixation. METHODS: Sixty five cases of complex (Schatzker type V and VI) tibial plateau fractures were treated with double-buttress plate fixation in our centre from September 2001 to September 2006 through two separate plate incisions. Fifty four patients were followed up for a period ranging from 12 to 48 months and evaluated for the functional and radiological outcomes by a series of standard questionnaire and measurement. RESULTS: Due to the good exposure without any extensive soft-tissue dissection of the double-buttress plate fixation, the fractures in all 54 patients were healed and the treatment achieved greater than 90% of satisfactory-to-excellent rates of reduction. The mean time of bone union was 15.4 weeks (range, 12-30 weeks), and the mean time of full weight-bearing was 18.7 weeks (range, 14-26 weeks). At the final follow-up visit, no patients showed knee instability; the mean range of motion was 107.6 degrees (range, 85 degrees -130 degrees ). For all patients, no statistically significant difference in the functional outcomes was observed between their 6-months and final follow-up visits; or in the radiological findings between their immediate postoperative and final follow-up examinations. CONCLUSION: Double-buttress plate fixation is a feasible treatment option for bilcondylar and complex tibial plateau fractures. Although technically demanding, it offers reliable stability without additional postoperative adjuvant external fixation, and at the same time avoids extensive soft tissue dissection, allowing the early painless range of motion.

Single-chain antibody/activated BID chimeric protein effectively suppresses HER2-positive tumor growth.

BH3-interacting domain death agonist (BID) is a crucial element in death signaling pathways and is recognized as an intracellular link connecting the intrinsic mitochondrial apoptotic and extrinsic death receptor-mediated apoptotic pathways. Herein, we describe experiments conducted with a fusion protein, which was generated by fusing a human epidermal growth factor receptor-2 (HER2)-specific single-chain antibody with domain II of Pseudomonas exotoxin A and the truncated active BID (tBID). These experiments extend our previous work on several other immuno-proapoptotic proteins. Specifically, by excluding cells with undetectable HER2, we showed that the secreted immuno-tBID molecule selectively recognized and killed HER2-overexpressing tumor cells in vitro by attacking their mitochondria and inducing their apoptotic death. This apoptosis could only be inhibited partially by caspase pan-inhibitor zVAD and mitochondrial protector TAT-BH4. Subsequently, we transferred the immuno-tbid gene into BALB/c athymic mice bearing HER2-positive tumors together with other immuno-proapoptotic proteins using i.m. injections of liposome-encapsulated vectors. The expression of the immuno-tbid gene suppressed tumor growth and prolonged animal survival significantly. We also shortened the translocation domain of Pseudomonas exotoxin A II to only 10-amino acid sequence, which were crucial for furin cleavage. The new recombinant molecule retained the translocation efficiency and the ability of specific killing HER2-positive tumor cells. Our data showed that, compared with the toxins employed before, the chimeric immuno-tBID molecule can not only specifically recognize HER2-positive tumor cells but also certainly induce apoptosis even in the presence of zVAD and TAT-BH4, thereby suggesting an alternative approach to treating HER2/neu-positive tumors.

Allogeneic tumor vaccine produced by electrofusion between osteosarcoma cell line and dendritic cells in the induction of antitumor immunity.

OBJECTIVE: Fusion of dendritic cells, DCs, with tumor cells is an effective approach for delivering tumor antigens to DCs, and DC-tumor fusion cells are potent stimulators of T cells. However, the integration of allogeneic DC-osteosarcoma fusion cells has not been fully examined. This study was designed to investigate the antitumor effects of tumor vaccine produced by electrofusion between rat osteosarcoma cells and allogeneic DCs. METHODS: In the present study, we electrofused Wistar rat bone marrow-derived DCs to SD rat osteosarcoma cells (UMR106) and purified them by monoclonal antibody OX62 and magnetic beads. Coculture of SD or Wistar bone marrow derived T lymphocytes with DC-tumor fusion cells resulted in activation of T cells, and the proportion of CD8(+), CD4(+) cells was determined using flow cytometry. Then cytotoxic T lymphocytes, CTLs, assay was assessed according to results of MTT assay. RESULTS: After T cells were cultured with allogeneic DC-osteosarcoma fusion cells, DOF, and effective activation of T cells was observed. The proportion of CD8(+) cells in the SD T cell group increases from 34.16% before induction to 74.85%, while that of CD4(+) cells is from 63.35% to 71.75% in Wistar T cell group. The immunization using allogeneic DC-osteosarcoma vaccine induced UMR106-specific CTL responses which were statistically significant (P < 0.05) and the cytotoxic activity was inhibited by the treatment with anti-CD8 and anti-MHC-class I monoclonal antibodies but not with anti-CD4 and anti-MHC-class II antibodies. CONCLUSION: The present study provided valid evidence of integration of rat allogeneic DCs electrofused with tumor cells and analyzed their properties in T cell activation. The fusion cells may thus represent a promising strategy for DC-based immunotherapy of patients with osteosarcoma.

Dual specificity phosphatase 1 has a protective role in osteoarthritis fibroblast­like synoviocytes via inhibition of the MAPK signaling pathway.

Increasing evidence indicates the important role of inflammation in the pathogenesis and progression of osteoarthritis (OA). Dual specificity phosphatase 1 (DUSP1), a negative regulator of the mitogen­activated protein kinase (MAPK) signaling pathway, has anti­inflammatory properties. In the present study, the expression of DUSP1 was investigated in human OA fibroblast­like synoviocytes (FLSs), human normal FLSs and OA FLSs pretreated with dexamethasone at the mRNA and protein levels. Then, the activation of MAPK pathway proteins and the expression of matrix metalloproteinase­13 (MMP­13) and cyclooxygenase­2 (COX­2) were measured by western blot analysis in the three groups of cells. Dexamethasone induced the expression of DUSP1 and inhibited the activation of the MAPK pathway and reduced the expression of MMP­13 and COX­2 in OA FLSs. However, the role of DUSP1 remained unclear. To clarify this, the effects of overexpression of DUSP1 in OA FLSs were determined using a DUSP1­overexpressing lentivirus. The results demonstrated that overexpression of DUSP1 in OA FLSs inhibited the activation of the MAPK pathway and expression of OA­associated mediators. The findings of the present study indicate that DUSP1 has a protective role in OA FLSs and may be a potential target in the treatment of OA.

Closed reduction and percutaneous annulated screw fixation in the treatment of comminuted proximal humeral fractures.

BACKGROUND: Displaced proximal humeral fractures remain a challenge to orthopedic surgeons. OBJECTIVES: The purpose of this study was to evaluate the functional and radiological outcomes of patients with comminuted proximal humeral fractures treated with closed reduction and percutaneous screw fixation (CRPF). MATERIAL AND METHODS: The authors retrospectively reviewed 38 cases of displaced proximal humeral fractures (2-, 3- or 4-part fractures according to the Neer classification) that were treated using the CRPF technique from May 2009 to April 2013. From this group 26 patients were followed up for a period ranging from 9 to 24 months (averaging 12.9 months) and evaluated for the functional and radiological outcomes by a series of standard questionnaires and measurements. RESULTS: The fractures in all 26 patients were healed within an average time of 14.6 weeks (ranging from 11 to 27 weeks), and the mean interval between the operation and fully functional activity was 18.6 weeks (ranging from 15 to 32 weeks). At the final follow-up visit, no patient showed shoulder instability; the mean range of abduction motion was 146.5° (ranging from 72° to 180°). For all patients, no statistically significant difference in the functional outcomes was observed between their 6-month and final follow-up visits; or in the radiological findings between their immediate post-operative and final follow-up examinations. CONCLUSIONS: The CRPF technique is a safe and effective therapeutic option for comminuted proximal humeral fractures. Good stability is obtained and aggressive impairment of the soft tissue and periosteum around the fracture is avoided, which allows for an early painless range of motion. The technique promotes bone healing, prevents ischemic osteonecrosis of the head of the humerus and leads to few complications.

Ginsenoside Rh2 enhances the antitumor immunological response of a melanoma mice model.

The treatment of malignant tumors following surgery is important in preventing relapse. Among all the post-surgery treatments, immunomodulators have demonstrated satisfactory effects on preventing recurrence according to recent studies. Ginsenoside is a compound isolated from panax ginseng, which is a famous traditional Chinese medicine. Ginsenoside aids in killing tumor cells through numerous processes, including the antitumor processes of ginsenoside Rh2 and Rg1, and also affects the inflammatory processes of the immune system. However, the role that ginsenoside serves in antitumor immunological activity remains to be elucidated. Therefore, the present study aimed to analyze the effect of ginsenoside Rh2 on the antitumor immunological response. With a melanoma mice model, ginsenoside Rh2 was demonstrated to inhibit tumor growth and improved the survival time of the mice. Ginsenoside Rh2 enhanced T-lymphocyte infiltration in the tumor and triggered cytotoxicity in spleen lymphocytes. In addition, the immunological response triggered by ginsenoside Rh2 could be transferred to other mice. In conclusion, the present study provides evidence that ginsenoside Rh2 treatment enhanced the antitumor immunological response, which may be a potential therapy for melanoma.

[CCR7 silence by siRNA inhibits proliferation, invasion and promotes apoptosis of human MG63 osteosarcoma cells].

Objective To investigate the effect of siRNA-mediated chemokine receptor 7 (CCR7) silence on the proliferation, migration, invasion and apoptosis of human MG-63 osteosarcoma cells. Methods The study designed and synthesized siRNA targeting CCR7 (CCR7-siRNA). After MG63 cells were transfected with CCR7-siRNA, the expression of CCR7 was identified by Western blotting; cell apoptosis was detected by annexinV-FITC/PI double staining combined with flow cemetery; cell proliferation was tested by MTT assay; and cell migration and invasion abilities were examined by TranswellTM migration/invasion assays. Results CCR7 expression in MG63 cells was significantly inhibited after transfected with CCR7-siRNA. At the same time, cell proliferation, migration and invasion abilities were distinctly suppressed, and cell apoptosis rate increased. Conclusion Down-regulating CCR7 expression in MG63 cells could apparently inhibit cell proliferation, migration and invasion abilities of MG63 cells, and also induce cell apoptosis.

[Estrogen exerts anti-inflammatory effects by inhibiting NF-κB pathway through binding with estrogen receptor ß on synovicytes of osteoarthritis].

Objective To investigate the mechanism of estrogen's anti-inflammatory effects on synovial cells during the pathogenic process of osteoarthritis. Methods We isolated synovicytes from synovium tissues and identified the cells with flow cytometry. Then we detected the expression level of estrogen receptor ß (ERß) in synovicytes with immunofluorescence staining. The synovicytes were divided into control group, group pretreated with 10 ng/mL IL-1ß, group pretreated with 10 ng/mL IL-1ß and 10-7 mol/L estrogen, group pretreated with 10 ng/mL IL-1ß, 10-7 mol/L estrogen and specific antagonist of ERß, 10-5 mol/L tetrahydrocannabinol (THC). Thirty-six hours later, we observed the mRNA and protein levels of IκBα, phospho-IκBα (p-IκBα) and IL-6. Results Immunofluorescence staining showed the high expression level of ERß in synovicytes. In IL-1ß treated cells, IL-6 mRNA and protein level, IκBα mRNA and p-IκBα protein levels were elevated compared with the control group, while IκBα protein level declined. In the cells pretreated with IL-1ß and estrogen, the mRNA and protein levels of IL-6, IκBα and p-IκBα were inhibited compared with IL-1ß treated cells. THC blocked the effects of estrogen on the IL-1ß and estrogen treated cells, and the mRNA and protein levels of IL-6, IκBα and p-IκBα had no significant difference compared with IL-1ß treated cells. Conclusion The estrogen can restrain the activation of NF-κB pathway in synovicytes via ERß, thus playing a vital role in anti-inflammation.

VEGF silencing inhibits human osteosarcoma angiogenesis and promotes cell apoptosis via PI3K/AKT signaling pathway.

Vascular endothelial growth factor (VEGF) is one of the most potently angiogenic factors which promotes generation of tumor vasculature. VEGF is usually up-regulated in multiple cancers include osteosarcoma and gliomas. To further explore the potential molecular mechanism that inhibits tumor growth induced by interference of VEGF expression, we constructed an Lv-shVEGF vector and assessed the efficiency of VEGF silencing and its influence on U2OS cells. Our data demonstrated that Lv-shVEGF has high inhibition efficiency on VEGF expression, which inhibits proliferation and promotes apoptosis of U2OS cells in vitro. Our results also indicated that inhibition of VEGF expression suppresses osteosarcoma tumor growth in vivo, VEGF inhibition reduces osteosarcoma angiogenesis. We also found that the phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) activation was considerably reduced after osteosarcoma cells were treated with Lv-shVEGF. Taken together, our data demonstrated that VEGF silencing suppresses cells proliferation, promotes cells apoptosis and reduces osteosarcoma angiogenesis through inactivation of PI3K/AKT signaling pathway.

VEGF Silencing Inhibits Human Osteosarcoma Angiogenesis and Promotes Cell Apoptosis via PI3K/AKT Signaling Pathway.

Vascular endothelial growth factor (VEGF) is one of the most effective angiogenic factors that promote generation of tumor vasculature. VEGF is usually up-regulated in multiple cancers including osteosarcoma and glioma. To further explore the potential molecular mechanism that inhibits tumor growth induced by interference of VEGF expression, we constructed a Lv-shVEGF vector and assessed the efficiency of VEGF silencing and its influence in U2OS cells. The data demonstrate that Lv-shVEGF has high inhibition efficiency on VEGF expression, which inhibits proliferation and promotes apoptosis of U2OS cells in vitro. Our results also indicate that inhibition of VEGF expression suppresses osteosarcoma tumor growth in vivo and reduces osteosarcoma angiogenesis. We also found that the activations of phosphoinositide 3-kinase (PI3K) and protein kinase B (AKT) were considerably reduced after osteosarcoma cells were treated with Lv-shVEGF. Taken together, our data demonstrate that VEGF silencing suppresses cell proliferation, promotes cell apoptosis, and reduces osteosarcoma angiogenesis through inactivation of PI3K/AKT signaling pathway.

[Establishment and characteristics of a human chordoma cell line].

OBJECTIVE: To present an established human chordoma cell line for chordoma research. METHODS: The specimens pathologically identified as chordoma were cultured, using primary tissue culture in vitro. The surviving cells were analyzed by morphology, histochemical stain, cell cycling analysis, karyotype analysis, electron microscopic observation, heterotransplantation and study of invasive capacity in vitro. RESULTS: The newly established cell line CM-319 has been maintained in continual cultures for over 100 generations in two years. Its morphological observation, histochemical staining properties, electron microscopic observation and heterotransplantation showed the common characteristics of chordoma. The doubling time of cells was about 33 hours. Cell cycle analysis showed: G(1) 55.6%, G(2) 21.9% and S 22.5%, G(2)/G(1) = 1.90. Chromosome analysis showed a hypotriploid feature and the success rate of heterotransplantation was 100%. It is capable of invasion in vitro. CONCLUSION: CM-319, as a cell line derived from human chordoma cells, may serve for further studies of chordoma.

Thoraco-umbilical flap: experience with 33 cases.

From August, 1996 to June, 2000, 33 patients received transfer of free thoraco-umbilical flaps for repair of various soft-tissue defects. The size of the flaps ranged from 10 to 40 cm in length and 8 to 25 cm in width, with blood supply of the flaps derived from the largest periumbilical perforating branch of the deep inferior epigastric vessels. The indications of this flap included complex extremity trauma or large skin loss resulted from soft tissue tumor resection, either acute or postprimary. The overall success rate was 100% in the 33 cases. The donor area was closed directly with 10- to 12-cm-wide flaps, leaving an inconspicuous scar, whereas larger flaps required skin grafting. A 2-year follow-up found uneventful healing of all the flaps with minimal donor abdominal morbidity.

Homologous mesenchymal stem cells promote the emergence and growth of pulmonary metastases of the rat osteosarcoma cell line UMR-106.

Osteosarcoma (OS) is the most frequent primary bone sarcoma and tends to develop pulmonary metastasis. Studies have shown that mesenchymal stem cells (MSCs) are involved in OS growth and metastasis, but the mechanism remains unclear. The aim of the present study was to identify whether homologous MSCs could promote the growth and metastasis of OS in rats with a normal immune system. The OS cell line, UMR-106, which originally derives from a Sprague-Dawley (SD) rat-transplantable osteogenic sarcoma with an osteoblastic phenotype, has a strong carcinogenic capability and a high lung metastasis. Xenotransplanted models of UMR-106 with or without MSCs injected through the tibia (IT) or caudal vein (IV) were established. SD rats were randomly divided into six groups: Control, UMR-106 (IT), MSCs (IV), UMR-106 (IT) + MSCs (IV), UMR-106 (IV) and UMR-106 (IV) + MSCs (IV). Following injection, all rats were sacrificed at week 5, and the volume and quantity of metastatic sarcoma and the serum alkaline phosphatase levels were measured. There was no metastatic sarcoma in the liver, spleen and kidney in all groups. The rats in the MSCs (IV) + UMR-106 (IV) group showed a significantly higher volume and number of pulmonary metastatic tumors than those of the UMR-106 (IV) group. In pulmonary metastatic tissues, MSCs were found in the MSCs (IV) + UMR-106 (IV) group, but not in the UMR-106 (IT) + MSCs (IV) group. Notably, the expression of vascular endothelial growth factor (VEGF) was increased in the MSCs + UMR-106 cells co-culture system. The present study indicated that MSCs can significantly promote the pulmonary metastasis of the rat OS cell line, UMR-106, with a normal immune system, and VEGF was involved in MSC-promoted UMR-106 emergence and growth of pulmonary metastasis.