Are Generative Pretrained Transformer 4 Responses to Developmental Dysplasia of the Hip Clinical Scenarios Universal? An International Review.

OBJECTIVE: There is increasing interest in applying artificial intelligence chatbots like generative pretrained transformer 4 (GPT-4) in the medical field. This study aimed to explore the universality of GPT-4 responses to simulated clinical scenarios of developmental dysplasia of the hip (DDH) across diverse global settings. METHODS: Seventeen international experts with more than 15 years of experience in pediatric orthopaedics were selected for the evaluation panel. Eight simulated DDH clinical scenarios were created, covering 4 key areas: (1) initial evaluation and diagnosis, (2) initial examination and treatment, (3) nursing care and follow-up, and (4) prognosis and rehabilitation planning. Each scenario was completed independently in a new GPT-4 session. Interrater reliability was assessed using Fleiss kappa, and the quality, relevance, and applicability of GPT-4 responses were analyzed using median scores and interquartile ranges. Following scoring, experts met in ZOOM sessions to generate Regional Consensus Assessment Scores, which were intended to represent a consistent regional assessment of the use of the GPT-4 in pediatric orthopaedic care. RESULTS: GPT-4's responses to the 8 clinical DDH scenarios received performance scores ranging from 44.3% to 98.9% of the 88-point maximum. The Fleiss kappa statistic of 0.113 (P = 0.001) indicated low agreement among experts in their ratings. When assessing the responses' quality, relevance, and applicability, the median scores were 3, with interquartile ranges of 3 to 4, 3 to 4, and 2 to 3, respectively. Significant differences were noted in the prognosis and rehabilitation domain scores (P < 0.05 for all). Regional consensus scores were 75 for Africa, 74 for Asia, 73 for India, 80 for Europe, and 65 for North America, with the Kruskal-Wallis test highlighting significant disparities between these regions (P = 0.034). CONCLUSIONS: This study demonstrates the promise of GPT-4 in pediatric orthopaedic care, particularly in supporting preliminary DDH assessments and guiding treatment strategies for specialist care. However, effective integration of GPT-4 into clinical practice will require adaptation to specific regional health care contexts, highlighting the importance of a nuanced approach to health technology adaptation. LEVEL OF EVIDENCE: Level IV.

Does the Skeletal Phenotype of Osteogenesis Imperfecta Differ for Patients With Non-COL1A1/2 Mutations? A Retrospective Study in 113 Patients.

BACKGROUND: Osteogenesis imperfecta (OI) is a heritable disease characterized by bone fragility and other extra skeletal manifestations. Most patients with OI have mutations in the COL1A1 or COL1A2 genes. However, a significant minority of patients with clinical OI have non-COL1A1/2 mutations, which have become easier to detect with the use of genetic panels. Traditional understanding of OI pathogenesis was expanded because of these new mutations, and their phenotypic-genotypic relationship is largely unknown. We hypothesized that patients with non-COL1A1/2 mutations have different skeletal clinical presentations from those with OI caused by COL1A1/2 mutations. METHODS: Patients were categorized into 4 groups according to our modified functional classification, namely, quantitative COL1A1/2 haploinsufficiency (group 1), qualitative COL1A1/2 dominant negative mutations (group 2), mutations indirectly affecting type I collagen synthesis, processing and posttranslational modification (group 3) and mutations altering osteoblast differentiation and function (group 4). Both group 3 and 4 were classified as non-COL1A1/2 mutation group. RESULTS: Of 113 OI patients included, 51 had COL1A1/2 quantitative haploinsufficiency mutations (group 1), 39 had COL1A1/2 qualitative dominant negative mutations (group 2), and 23 patients had OI caused by mutations in 1 of 9 other noncollagen genes (groups 3/4). Patients with non-COL1A1/2 mutations (groups 3 and 4) have severe skeletal presentations. Specifically, OI patients with non-COL1A1/2 mutations experienced more perinatal fractures, vertebral compression fractures and had more long bone deformities. Although the occurrence of scoliosis was similar, the cobb angle was larger in the non-COL1A1/2 mutation group. Radial head dislocations, ossification of interosseous membrane, extraskeletal ossification, cervical kyphosis, and champagne glass deformity of the pelvis were more frequent in this group. CONCLUSIONS: The clinical phenotype of OI in patients with non-COL1A1/2 is severe and has unique features. This information is useful for clinical diagnosis and prognosis. LEVEL OF EVIDENCE: Level III.

Complications of Elongating Intramedullary Rods in the Treatment of Lower Extremity Fractures for Osteogenesis Imperfecta: A Meta-Analysis of 594 Patients in 40 Years.

BACKGROUND: Osteogenesis imperfecta is a collagen mutation-related disease characterized by bone fragility and other extraskeletal manifestations. Intramedullary fixation for deformity correction or fracture is the standard care. Elongating rods are designed to accommodate growth, with the aim of preventing additional operations and/or complications associated with nonelongating rods. Although elongating rods have been in use for many years, estimates of the clinical outcomes vary. We conducted a systematic review and meta-analysis to synthesize the literature on outcomes of elongating rods and nonelongating rods. Meta-analysis was used to compare the complication rates and reoperation rates. METHODS: We conducted the literature search, systematic review, and meta-analysis in accordance with Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines. Comparative cohort studies and large case series detailing complication rates and reoperation rates of elongating and nonelongating rods were included. Random effect models were used to summarize the complication rates and reoperation rates of intramedullary rod procedures. RESULTS: A total of 397 studies were identified and 24 studies were included in the final cohort. Compared with rates from nonelongating rods, osteogenesis imperfecta Patients using elongating rods had a complication rate of 61% and a reoperation rate of 78%. Reoperation rates dropped with succeeding generations of elongating rods. Pooling data from 600 patients, we identified a 9% complication rate per rod per follow up year and 5% reoperation rate per rod and per follow up year in the cohort of elongating rod fixation. The Bailey-Dubow rod had the highest complication rate per rod per follow up year (12%), largely because of its T piece relate problems. The most popular fixator Fassier-Duval rod had a complication rate per rod per follow up year of 9%. About 68% of complications were mechanical-biological related. CONCLUSION: Pooling data from published literature demonstrates the advantage of elongating rods over nonelongating rods. However, as high as 9% complication rate per rod per follow up year was associated with elongating fixation. Notably, most complications are both mechanical and biological related. LEVEL OF EVIDENCE: Level III.

Eosinophilic Granuloma of the Thumb Presenting in a 4-Month-Old Child: Case Report and Review of the Literature.

Eosinophilic granuloma (EG) is a benign bone tumor of unknown origin usually seen in children. It is typically found in flat and long bones of the skull and of the appendicular skeleton, respectively. Small bones are rarely affected. The diagnosis and treatment of EG can be challenging as differential diagnosis includes several disorders that can cause osteolytic lesions. Moreover, surgical treatment can be difficult due to the small size of the bone and surrounding structures. Here we describe a case of EG of the proximal phalanx of the thumb (P1 D1) presenting in a 4-month-old boy with persistent swelling and limited range-of-motion of the interphalangeal joint in the left thumb. Over a 6-year follow-up, no sign of relapse was observed. Moreover, the curetted bone did regenerate, and it appeared homogenously dense as normal trabecular bone on the last plain radiographs; the patient was symptom-free at the last follow-up visit. Clinical presentation, treatment, pathoanatomy, localization, and complication of this form of tumor are discussed, and all previously reported cases are reviewed to give a more comprehensive picture of EG of the hand and fingers.

Single Bone Fixation versus Both Bone Fixation for Pediatric Unstable Forearm Fractures: A Systematic Review and Metaanalysis.

BACKGROUND: It is uncertain whether single bone fixation is comparable to both bone fixation in the treatment of unstable both bone forearm fractures in children. MATERIALS AND METHODS: A systematic review using PubMed, Embase, and Cochrane Library database searches was performed on October 1, 2015 on English language scientific literature only. Clinical study designs comparing single bone fixation with both bone fixation of pediatric both bone forearm fractures were included. Studies of only one treatment modality were excluded from the study. Studies eligible for inclusion were assessed using the risk of bias tool for nonrandomized studies. RESULTS: Metaanalysis points to no significant differences in re-angulation, loss of rotation, union time and complications between single bone and both bone fixation. However, the published research lacks quality. CONCLUSIONS: Despite scattered evidence and small sample sizes, the metaanalysis suggests single bone fixation can be considered a suitable alternative for both bone forearm fractures in children, as it carries less time in surgery and less cost without compromise in final functional outcome compared to double-bone fixation.

Post-operative radiograph assessment of children undergoing closed reduction and spica cast immobilization for developmental dysplasia of the hip: does experience matter?

PURPOSE: Closed reduction and spica cast immobilization are routinely used for young patients with developmental dysplasia of the hip with reducible hips. Our primary objective was to assess the interpretation quality of immediate post-operative pelvis radiographs after treatment. METHODS: A series of 28 randomly selected patients (30 hips) with pre- and post-operative pelvis radiographs and post-operative magnetic resonance imaging were included. Each was presented twice with an interval of two weeks, in alternating orders. Raters with different experience and specialties from different institutions rated the quality of reduction (hip in or out) after treatment. RESULTS: Thirteen surgeons and three radiologists evaluated 30 hips (28 patients). Agreement was not satisfactory (κ = 0.12). Experienced clinicians demonstrated similar agreement to inexperienced raters (κ = 0.04). Consistency at a two week interval was moderate (κ = 0.48, percent of agreement at 82%). The mean number of errors from the two ratings were 8.6 ± 2.5 and 8.9 ± 2.7, respectively (P = 0.72). There was no significant difference between surgeons with different levels of experience; radiologists did better than surgeons, but the difference was insignificant. Raters from different institutions had similar performance in poor judgment. CONCLUSIONS: Our results show poor concordance between observers and ratings. Post-operative radiographs are unreliable for assessing the quality of hip reduction. The level of experience, subspecialty, and geographical origin do not impact the radiographic assessment. Based on the present findings, we recommend performing post-operative magnetic resonance imaging rather than anteroposterior pelvis radiograph to assess the hip. Compared to standard radiographs, magnetic resonance imaging allows more reliable interpretation while decreasing radiation exposure.

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.

Delayed treatment of septic arthritis in the neonate: A review of 52 cases.

There is still controversy on the management of septic arthritis in neonates. This study aims to investigate the treatment of septic arthritis in neonates.We reviewed 52 neonates (37 males and 15 females) with septic arthritis in our hospital during 2004 to 2015. The mean age at onset of infection was 17.5 ±â€Š7.6 days, mean age at admission was 32.6 ±â€Š10.7 days. A total of 56 joints were involved (22 knees, 18 shoulders, 13 hips, and 3 other joints). Thiryt-six patients underwent surgical drainage, 14 patients were treated nonoperatively, 2 families refused treatment. Forty-four patients (48 joints) were followed for 4.5 ±â€Š1.2 years. Based on treatment, these 48 joints were divided into an operative group and a nonoperative group. Clinical presentations, imaging examination results, treatments, and outcomes were analyzed.Among the patients who were followed-up, the time from onset to treatment in the operatively managed group (12.7 ±â€Š8.1 days) was significantly shorter than that in the conservatively managed group (20.0 ±â€Š8.2 days). There were no significant differences between both groups on the age at onset, age at admission, imaging score, length of hospital stay, WBC counts, and intravenous medication time. Thirty-five sites (72.9%) recovered completely. There was no significant difference on recovery rate between operative and nonoperative group. Only 33.3% of the hips recovered, this was significantly lower than that of knee/ankle (85.0%) and shoulder/elbow (78.9%). Sequels were found in 13 joints. Logistic regression indicated that sex, imaging score, and hip joint involvement were predictors of sequel. One point of imaging score increased the risk of sequels by a factor of 2.960, and hip joint involvement increased the risk of sequels by a factor of 12.712. Females were more likely to have sequels than males.Surgical drainage is recommended for early diagnosed neonatal septic arthritis and hip infections. A conservative approach may be more efficient for patients whose diagnosis and treatment had been delayed for more than 2 weeks. Antibiotics should be administered intravenously for 2 weeks and then orally for another 2 weeks. First-generation cephalosporin and clindamycin are recommended empirical antibiotics before causative agent and its resistance pattern are known.

A systematic review of association studies of common variants associated with idiopathic congenital talipes equinovarus (ICTEV) in humans in the past 30 years.

The genetic cause of idiopathic congenital talipes equinovarus (ICTEV) is largely unknown. We performed a systematic review to describe the findings from 21 studies that have examined the genetic variants related to ICTEV, and to evaluate the quality of reporting. We found that ICTEV was positively associated with Hox family genes, collagen family genes, GLI3, N-acetylation genes, T-box family genes, apoptotic pathway genes, and muscle contractile family genes. Negative and controversial results were also discussed, and several genes associated with ICTEV were identified. Due to the limitation of the included studies, rare coding variants should be further investigated, sample size should be enlarged, and candidate genes should be replicated in larger ICTEV populations. Epigenetic study, pathways, chromosome capture, and detailed gene-environment interaction will also allow further elucidation of factors involved in ICTEV pathogenesis and may shed light on diagnosis and timely and accurate interventions.

Analysis of Selenium Levels in Osteosarcoma Patients and the Effects of Se-Methylselenocysteine on Osteosarcoma Cells In Vitro.

The form of selenium appears to be important for preventing cancer in humans. Here, we evaluated selenium levels in the serum and bone tissue samples from osteosarcoma patients using atomic absorption spectrometry. The in vitro effects of Se-methylselenocysteine (Se-MSC) on growth, cell cycle status, and apoptosis of osteosarcoma cells were assessed using the WST-1 assay, Hoechst 33342/propidium iodide staining, and flow cytometry, respectively. In osteosarcoma cases, the mean serum selenium levels in osteosarcoma tissue and normal bone were 0.08 mg/kg and 0.03 mg/kg, respectively (P < 0.05). Serum selenium levels in osteosarcoma and non-osteosarcoma cases were 0.09 mg/L and 0.08 mg/L, respectively (P > 0.05). Se-MSC-treated MG63 cells showed altered cellular morphology, decreased viability in a time- and dose-dependent manner, and an increase in the sub-G1 cell population. Se-MSC also downregulated Bcl-2 expression and upregulated Bax. Se-MSC inhibited the proliferation of the drug-resistant osteosarcoma cell line Saos-2/MTX300 and enhanced the inhibitory effect of pirarubicin on MG63 cells. Our data demonstrate that selenium levels are significantly higher in osteosarcoma tissue than normal bone tissue in osteosarcoma patients. The results also support the anticancer effects of Se-MSC in osteosarcoma. Further development of Se-MSC as an ancillary chemotherapy agent in osteosarcoma is warranted.

IRX1 hypomethylation promotes osteosarcoma metastasis via induction of CXCL14/NF-κB signaling.

Osteosarcoma is a common malignant bone tumor with a propensity to metastasize to the lungs. Epigenetic abnormalities have been demonstrated to underlie osteosarcoma development; however, the epigenetic mechanisms that are involved in metastasis are not yet clear. Here, we analyzed 2 syngeneic primary human osteosarcoma cell lines that exhibit disparate metastatic potential for differences in epigenetic modifications and expression. Using methylated DNA immunoprecipitation (MeDIP) and microarray expression analysis to screen for metastasis-associated genes, we identified Iroquois homeobox 1 (IRX1). In both human osteosarcoma cell lines and clinical osteosarcoma tissues, IRX1 overexpression was strongly associated with hypomethylation of its own promoter. Furthermore, experimental modulation of IRX1 in osteosarcoma cell lines profoundly altered metastatic activity, including migration, invasion, and resistance to anoikis in vitro, and influenced lung metastasis in murine models. These prometastatic effects of IRX1 were mediated by upregulation of CXCL14/NF-κB signaling. In serum from osteosarcoma patients, the presence of IRX1 hypomethylation in circulating tumor DNA reduced lung metastasis-free survival. Together, these results identify IRX1 as a prometastatic gene, implicate IRX1 hypomethylation as a potential molecular marker for lung metastasis, and suggest that epigenetic reversion of IRX1 activation may be beneficial for controlling osteosarcoma metastasis.

miR-199a-3p negatively regulates the progression of osteosarcoma through targeting AXL.

Dysregulation of micro-RNAs has been shown to contribute to multiple tumorigenic processes, as well as to correlate with tumor progression and prognosis. miR-199a has been shown to be dysregulated in many different tumor types; however, the association between miR-199a and the clinicopathological features of osteosarcoma is unknown, and the target gene for miR-199a and the regulatory mechanism are also unknown. In this study, we demonstrated that miR-199a-3p is expressed at low levels in osteosarcoma cells, which may inhibit the migration and invasion of these tumor cells. The downregulation of miR-199a-3p expression is significantly correlated with the recurrence and lung metastasis of patients with osteosarcoma. Using multivariate Cox regression analysis, low level of expression of miR-199a-3p was shown to be an independent predictor for worse prognosis in osteosarcoma. Furthermore, we showed that miR-199a-3p mimics can decrease the expression of the mRNA and protein of the receptor tyrosine kinase AXL, and miR-199a-3p targets directly the 3'-UTR of AXL mRNA, suggesting that miR-199a-3p may downregulate the expression of the AXL gene to inhibit the progression of osteosarcoma. In patients' osteosarcoma samples, we also showed a statistically significant inverse relation between the levels of miR-199a-3p and AXL, which is consistent with the results in osteosarcoma cell lines. Interestingly, miR-199a-3p mimics reduced the level of phosphorylation of AKT. Together with the previous data, we conclude that miR-199a-3p negatively contributes to the progression of osteosarcoma by downregulating the expression of AXL mRNA and protein. By this mechanism, a regulatory pathway comprised of miR-199a-3p and AXL may exist in osteosarcoma cells, which may as a result regulate the progression of osteosarcoma through the AKT pathway.

[Expression of chemokine CXCL14 in primary osteosarcoma and its association with prognosis].

OBJECTIVE: To detect the expression of CXCL14 in human osteosarcoma cell lines and tissues and investigate its association with the prognosis of the patients. METHODS: RT-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. RESULTS: Significant 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). CONCLUSION: CXCL14 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.

Gas6/Axl mediates tumor cell apoptosis, migration and invasion and predicts the clinical outcome of osteosarcoma patients.

Dysregulation of the receptor tyrosine kinase Axl and its ligand Gas6 has been shown to promote multiple tumorigenic processes, as well as to correlate with worse prognosis in many different tumor types. However, studies of Axl expression and function in osteosarcoma have rarely been reported. In this study, we report that activated Axl is highly expressed in osteosarcoma cells, and this expression is significantly correlated with the recurrence and lung metastasis of osteosarcoma patients. High expression of activated Axl was an independent predictor for worse prognosis in osteosarcoma. Additionally, we confirmed a strong positive correlation between P-Axl and MMP-9 expression in those osteosarcoma patients. In osteosarcoma cell lines MG63 and U2OS, 200 ng/ml rhGas6 could cause obvious increase of P-Axl expression within 30 min, consistent with the expression of P-AKT. In both of the cell lines, Axl activated by rhGas6 could protect the tumor cells from apoptosis caused by serum starvation, and promote tumor cells' migration and invasion in vitro. Together with previous data, these studies suggest that activated Axl participate in the progression of osteosarcoma by resisting tumor cells apoptosis and promoting their migration and invasion, which may be linked to the expression of MMP-9. In the mechanism, AKT signaling pathway may contribute to the function of P-Axl in osteosarcoma rather than ERK pathway.

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.

Suboptimal chemotherapy is an adverse prognostic factor in osteosarcoma.

BACKGROUND: We sought to determine whether suboptimal chemotherapy compromised the prognosis of osteosarcoma patients. METHODS: A total of 132 eligible patients who underwent chemotherapy between 1998 and 2008 were identified in our database. Information regarding patient demographics, clinical characteristics, and survival status were extracted for analysis. Optimal chemotherapy was defined as receipt of ≥80% of the planned dose intensity of prescribed agents within the planned durations. RESULTS: The use of optimal chemotherapy resulted in an overall survival benefit with P = 0.006. Patients who failed to complete the optimal chemotherapy protocol had a dismal prognosis of 30.8% overall survival over five years, whereas those who completed the optimal chemotherapy had an overall survival rate over five years of 65.3%. Based on multivariate analysis, patients who were treated with a suboptimal protocol had a higher risk of relapse, metastasis and mortality. The hazard ratio (HR) of recurrence or death for the suboptimal chemotherapy group was as high as 2.512 over that of the optimal chemotherapy group (HR = 2.512, 95% confidence interval = 1.242 to 3.729). CONCLUSIONS: Chemotherapy is a significant independent prognostic variable, and suboptimal chemotherapy was found to have a detrimental effect on the outcome of patients with osteosarcoma.

Glycogen synthase kinase-3ß, NF-κB signaling, and tumorigenesis of human osteosarcoma.

BACKGROUND: Glycogen synthase kinase-3ß (GSK-3ß), a serine/threonine protein kinase, may function as a tumor suppressor or an oncogene, depending on the tumor type. We sought to determine the biological function of GSK-3ß in osteosarcoma, a rare pediatric cancer for which the identification of new therapeutic targets is urgent. METHODS: We used cell viability assays, colony formation assays, and apoptosis assays to analyze the effects of altered GSK-3ß expression in U2OS, MG63, SAOS2, U2OS/MTX300, and ZOS osteosarcoma cell lines. Nude mice (n = 5-8 mice per group) were injected with U2OS/MTX300, and ZOS cells to assess the role of GSK-3ß in osteosarcoma growth in vivo and to evaluate the effects of inhibitors and/or anticancer drugs on tumor growth. We used an antibody array, polymerase chain reaction, western blotting, and a luciferase reporter assay to establish the effect of GSK-3ß inhibition on the nuclear factor-κB (NF-κB) pathway. Immunochemistry was performed on primary tumor specimens from osteosarcoma patients (n = 74) to determine the relationship of GSK-3ß activity with overall survival. RESULTS: Osteosarcoma cells with low levels of inactive p-Ser9-GSK-3ß formed colonies in vitro and tumors in vivo more readily than cells with higher levels and cells in which GSK-3ß had been silenced formed fewer colonies and smaller tumors than parental cells. Silencing or pharmacological inhibition of GSK-3ß resulted in apoptosis of osteosarcoma cells. Inhibition of GSK-3ß resulted in inhibition of the NF-κB pathway and reduction of NF-κB-mediated transcription. Combination treatments with GSK-3ß inhibitors, NF-κB inhibitors, and chemotherapy drugs increased the effectiveness of chemotherapy drugs in vitro and in vivo. Patients whose osteosarcoma specimens had hyperactive GSK-3ß, and nuclear NF-κB had a shorter median overall survival time (49.2 months) compared with patients whose tumors had inactive GSK-3ß and NF-κB (109.2 months). CONCLUSION: GSK-3ß activity may promote osteosarcoma tumor growth, and therapeutic targeting of the GSK-3ß and/or NF-κB pathways may be an effective way to enhance the therapeutic activity of anticancer drugs against osteosarcoma.

Expression and prognostic relevance of PRAME in primary osteosarcoma.

The preferentially expressed antigen of melanoma (PRAME), a cancer-testis antigen with unknown function, is expressed in many human malignancies and is considered an attractive potential target for tumor immunotherapy. However, studies of its expression and function in osteosarcoma have rarely been reported. In this study, we found that PRAME is expressed in five osteosarcoma cell lines and in more than 70% of osteosarcoma patient specimens. In addition, an immunohistochemical analysis showed that high PRAME expression was associated with poor prognosis and lung metastasis. Furthermore, PRAME siRNA knockdown significantly suppressed the proliferation, colony formation, and G1 cell cycle arrest in U-2OS cells. Our results suggest that PRAME plays an important role in cell proliferation and disease progression in osteosarcoma. However, the detail mechanisms of PRAME function in osteosarcoma require further investigation.

High serum alkaline phosphatase cooperating with MMP-9 predicts metastasis and poor prognosis in patients with primary osteosarcoma in Southern China.

BACKGROUND: Osteosarcoma is a malignant tumor with high ability to form invasion and metastasis. Identifying prognostic factor in osteosarcoma is helpful to select those patients for more aggressive management. Our study evaluated serum alkaline phosphatase (ALP) cooperating with matrix metalloproteinase-9 (MMP-9) as an important prognostic predictor for local recurrence and distant metastasis of osteosarcoma. METHODS: 177 cases were included from the osteosarcoma patients treated at 1st Affiliated Hospital of Sun Yat-sen University (1999-2008). Pre-chemotherapy serum ALP (pre-ALP) were studied and correlated with tumor recurrence, lung metastasis and patient survival. MMP-9 protein in tumor tissues was detected by immunohistochemistry and correlated with pre-ALP level. RESULTS: Pre-ALP were partitioned into normal, high, and very high groups, in each group the incidence of metastases was 12.2%, 21.2% and 34.6%, respectively (p = 0.007). In the three groups the mean disease-free survival (DFS) was 57 ± 3.15, 28 ± 3.57 and 14 ± 3.35 months, respectively (p < 0.001); overall survival (OS) was 92 ± 26.89, 39 ± 8.61 and 17 ± 5.07 months, respectively (p < 0.001). By multivariate analysis, elevated serum pre-ALP were associated with shorter DFS (p = 0.018) and OS (p = 0.031). If elevated ALP levels decreased after clinical treatment, the incidence of lung metastasis rate decreased (p = 0.028); DFS and OS were both prolonged (p < 0.001). Pre-ALP was also positively correlated with MMP-9 expression (p = 0.015) in tumor tissue. CONCLUSIONS: Pre-ALP was an independent prognostic factor for the survival of osteosarcoma patients in south China, and correlated with MMP-9 expression and lung metastasis. ALP can also serve as a prognostic marker for treatment, and merit large-scale validation studies.