LDOC1 regulates Wnt5a expression and osteosarcoma cell metastasis and is correlated with the survival of osteosarcoma patients.

Osteosarcomas are common bone malignancies in children and adolescents. LDOC1 (leucine zipper, down-regulated in cancer 1), a tumor suppressor, is down-regulated in many cancers. In this study, we investigated the role of LDOC1 in tumor metastasis and its prognostic significance in osteosarcomas. We established osteosarcoma cells stably expressing LDOC1, driven by an HIV-based lentiviral system. We investigated the impact of LDOC1 on migration and invasion abilities in these cells using a transwell assay. LDOC1-associated changes in expression of metastasis-promoting genes were analyzed with a quantitative real-time polymerase chain reaction primer array. A xenograft tumor model (n = 7 mice/group) was used to assess the effect of LDOC1 on osteosarcoma metastasis in vivo. The overall survival and disease-free survival of osteosarcoma patients (n = 74) were analyzed retrospectively based on immunohistochemical analysis of LDOC1 levels in tumors and Kaplan-Meier analysis. LDOC1-expressing osteosarcoma cells displayed decreased migration and invasion in vitro. The quantitative real-time polymerase chain reaction primer array data showed that increased LDOC1 expression up-regulated many metastasis-suppressor genes. In the xenograft model, micro-computed tomography imaging data indicated that increased LDOC1 expression is associated with weaker lung metastasis ability. The Wnt5a signaling pathway promotes osteosarcoma metastasis; LDOC1 expression decreased Wnt5a levels in osteosarcoma cells. Kaplan-Meier analysis showed that higher LDOC1 expression was associated with improved osteosarcoma patient overall survival and disease free survival (p = 0.022). Our data show that LDOC1 is a tumor suppressor in osteosarcoma, and that it regulates metastasis of osteosarcoma cells. Furthermore, LDOC1 might be a valuable prognostic marker in osteosarcomas.

The glycogen synthase kinase-3ß/nuclear factor-kappa B pathway is involved in cinobufagin-induced apoptosis in cultured osteosarcoma cells.

Cinobufagin, a major component of cinobufacini (huachansu), is an important cardenolidal steroid. Several studies have suggested that cinobufagin has potent anti-cancer effects. The present study examines the apoptosis-inducing activity and the underlying mechanism of action of cinobufagin in osteosarcoma (OS) cells. Our results showed that cinobufagin potently inhibited the proliferation of U2OS, MG63 and SaOS-2 cells. Significant increases in G2/M cell-cycle arrest and apoptosis in OS cells were also observed. The expression levels of several apoptotic proteins were assessed after cinobufagin treatment in U2OS cells. Among them, xIAP, cIAP-1, survivin and Bcl-2 levels decreased remarkably, while the levels of Bax and cleaved-PARP increased. Furthermore, we validated the inhibition of GSK-3ß/NF-κB signaling following cinobufagin treatment. Western blots showed a decrease in nuclear p65 protein expression after exposure to different concentrations of cinobufagin, while the phosphorylation of GSK-3ß was simultaneously increased. Transduction with constitutively active forms of GSK-3ß could protect against the downregulation of p65 and upregulation of cleaved-PARP that are induced by cinobufagin treatment. However, combined treatment with cinobufagin and SB216367 resulted in a significant reduction in p65 and an increase in cleaved-PARP in U2OS cells. Altogether, these results show that cinobufagin is a promising agent for the treatment of OS. These studies are the first to reveal the involvement of the GSK-3ß/NF-κB pathway in cinobufagin-induced apoptosis.

[Treatment of displaced humeral supracondylar fractures in children with external fixation using plaster or splint].

OBJECTIVE: To investigate the therapeutic effects of closed reduction and external fixation (plaster or splint) for the treatment of displaced humeral supracondylar fractures in children. METHODS: From March 2007 to September 2009,33 children (15 female and 18 male) with humeral supracondylar fractures treated in our hospital, ranging from 3 to 12 years old with an average of 6.4 years old. All the fractures were extension-type injuries, the flexion injures were excluded in our study. The humeral supracondylar fractures were classified according to Gartland classification. There were 21 Type H and 12 type III. In the initial treatment, all the patients were treated with closed reduction and external immobilization. The blood supply of the damaged upper extremity was evaluated before and after treatment. Clinical assessment was obtained at final follow-up using Flynn criteria, and radiologic assessment was obtained using Baumann and lateral humerocapitellar angles. RESULTS: All the children were treated successfully with closed reduction in the initial time; 24 children maintained limb alignment by external immobilization. Nine patients lost position due to the swelling around the elbow which affected unstable external fixation during the follow-up, 5 of which were treated with a repeated closed reduction and internal fixation with Kirschner wires, 4 of which were treated with traction. Thirty-one patients had a satisfactory outcome and 2 patients had an unsatisfactory outcome according to the Flynn criteria at the latest follows-up. CONCLUSION: Closed reduction and external stabilization is an important method for the treatment of displaced humeral supracondylar fractures in children. Making regular follow-up visits after closed reduction and casting is important for patients to maintain acceptable alignment, avoid complications and diagnose any loss of reduction.

[Comparison percutaneous cervical disc nucleoplasty and cervical discectomy for the treatment of cervical disc herniation].

OBJECTIVE: To compare the therapeutic effect of percutaneous cervical disc nucleoplasty (PCN group) and percutaneous cervical discectomy (PCD group) for the treatment of cervical disc herniation. METHODS: A retrospective study was carried out from July of 2002 to December of 2004, and there were 80 cervical disc herniation cases who were operated by PCN (42 cases) or PCD (38 cases). The time of operation, clinical result and the stability of cervical spine after operation were evaluated and compared between 2 groups. RESULTS: All cases had been followed up from 6 months to 26 months, average (12 +/- 5) months on the PCN group and (12 +/- 4) months on the PCD group, and there was no significant difference on 2 groups (t = -0.06, P = 0.953). All cases had been successfully operated. There was significant difference in the operation time between 2 groups (t = -21.70, P = 0.000). There was significant difference in the pre- and post-operation scores of each group (PCN group: t = 14.05, P = 0.000; PCD group: t = -14.79, P = 0.000). There was no significant difference in 2 groups of the clinical outcomes (z = -0.377, P = 0.706, > 0.05). There was no instability of cervical spine cases in 2 groups after operation (P > 0.05), and the cervical spine stability was no significant difference in pre- and-operation in each group. CONCLUSIONS: PCN and PCD for the treatment of cervical disc herniation achieves good outcomes and no difference on the stability of cervical spine. PCN and PCD is a safe, minimally invasive, short time of operation, less traumatic operation and excellent clinical outcome.