Predicting prognosis and immune status in sarcomas by identifying necroptosis-related lncRNAs.

BACKGROUND: Sarcomas are a type of highly heterogeneous malignant tumors originating from mesenchymal tissues. Necroptosis is intricately connected to the oncogenesis and progression of tumors. The main goal of this research is to assess the prognostic value of necroptosis-related lncRNAs (NRlncRNAs) in sarcomas and to develop a risk model based on NRlncRNAs to evaluate prognostic and immune status of the sarcomas. METHODS: We screened NRlncRNAs using the gene co-expression network, developed a prognostic risk model of sarcomas, and then verified the model. Following that, various bioinformatics analysis algorithms were employed to analyze the distinct characteristics of patients of the risk model. Furthermore, the function and regulatory mechanism of NRlncRNA SNHG6 in sarcomas were investigated through osteosarcoma cell experiments, such as qRT-PCR, Western blot, CCK-8, clone formation, and transwell assay. RESULTS: We successfully developed a NRlncRNAs-related prognostic risk model and screened 5 prognosis-related NRlncRNAs, with SNGH6 being the most significant for prognosis of patients. According to results, the significant differences exist in prognosis, clinical characteristics, and tumor immune status among patients of the risk model. The experiments of osteosarcoma cells demonstrated that NRlncRNA SNHG6 knockdown significantly attenuated the cells' proliferation, migration, and invasion. qRT-PCR and WB results showed that SNHG6 regulated AXL and AKT signaling. CONCLUSIONS: We have developed an innovative investigation on NRlncRNAs, which can serve as a reference for diagnosis, therapy, and prognosis of sarcomas. Additionally, we demonstrated that NRlncRNA SNHG6 regulated AXL and AKT signaling in osteosarcoma cells and the proliferation, migration, and invasion of tumor cells.

Artificial intelligence for diagnosis and prognosis prediction of natural killer/T cell lymphoma using magnetic resonance imaging.

Accurate diagnosis and prognosis prediction are conducive to early intervention and improvement of medical care for natural killer/T cell lymphoma (NKTCL). Artificial intelligence (AI)-based systems are developed based on nasopharynx magnetic resonance imaging. The diagnostic systems achieve areas under the curve of 0.905-0.960 in detecting malignant nasopharyngeal lesions and distinguishing NKTCL from nasopharyngeal carcinoma in independent validation datasets. In comparison to human radiologists, the diagnostic systems show higher accuracies than resident radiologists and comparable ones to senior radiologists. The prognostic system shows promising performance in predicting survival outcomes of NKTCL and outperforms several clinical models. For patients with early-stage NKTCL, only the high-risk group benefits from early radiotherapy (hazard ratio = 0.414 vs. late radiotherapy; 95% confidence interval, 0.190-0.900, p = 0.022), while progression-free survival does not differ in the low-risk group. In conclusion, AI-based systems show potential in assisting accurate diagnosis and prognosis prediction and may contribute to therapeutic optimization for NKTCL.

Localized and metastatic myxoid/round cell liposarcoma: clinical and molecular observations.

BACKGROUND: Myxoid liposarcoma (MLPS), a disease especially of young adults with potential for local recurrence and metastasis, currently lacks solid prognostic factors and therapeutic targets. The authors of this report evaluated the natural history and outcome of patients with MLPS and commonly deregulated protein biomarkers. METHODS: Medical records were retrospectively reviewed for patients who presented to the authors' institution with localized (n = 207) or metastatic (n = 61) MLPS (1990 to 2010). A tissue microarray of MLPS patient specimens (n = 169) was constructed for immunohistochemical analysis of molecular markers. RESULTS: The 5-year and 10-year disease-specific survival rates among patients with localized disease were 93% and 87%, respectively; male gender, age >45 years, and recurrent tumor predicted poor outcome. The local recurrence rate was 7.4%, and the risk of local recurrence was associated with recurrent tumors and nonextremity disease location. Male gender was the main risk factor for metastatic disease, which occurred in 13% of patients. Forty percent of patients who had localized disease received chemotherapy, mostly in the neoadjuvant setting. Immunohistochemical analysis revealed significantly higher expression of C-X-C chemokine receptor type 4 (CXCR4) and platelet-derived growth factor beta (PDGFR-ß) in metastatic lesions versus localized lesions. Tumors with a round cell phenotype expressed increased levels of CXCR4, p53, adipophilin, PDGFR-α, PDGFR-ß, and vascular endothelial growth factor relative to myxoid phenotype. Only the receptor tyrosine kinase encoded by the AXL gene (AXL) was identified as a prognosticator of disease-specific survival in univariate analysis. CONCLUSIONS: In this study, the authors identified clinical and molecular outcome prognosticators for patients with MLPS as well as several potential therapeutic targets.

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.

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.

Involvement of the PI3K/Akt pathway in myxoid/round cell liposarcoma.

The molecular determinants involved in the progression of myxoid liposarcoma to increased cellularity/round cell change are poorly understood. We studied the PI3K/Akt pathway in myxoid and round cell liposarcomas using a tissue microarray composed of 165 tumors from 111 patients, and mutational analysis of PIK3CA in 44 cases. Activating PIK3CA mutations were found in 6/44 cases, 14%; mutations were more frequent in round cell vs myxoid tumors (5/15, 33% vs 1/29, 3%; P=0.013). Complete loss of PTEN, an alternative mechanism for PI3K/Akt activation, was found in 13/111 (12%) cases and was mutually exclusive with PIK3CA mutation. Strong IGF1R expression was demonstrated in 14/39 (36%) of round cell and 11/58 (19%) of myxoid tumors (P=0.062). Activation of the PI3K pathway was confirmed using immunohistochemical analysis for downstream targets phospho-S6 ribosomal protein and phospho-4EBP1. Phospho-4EBP1 was increased in round cell tumors compared with myxoid tumors (24/30, 80% vs 25/44, 57%; P=0.038) or tumors with treatment effect (10/24, 42%; P=0.02). Phospho-S6 was highly expressed in both myxoid and round cell tumors (29/47, 62% and 14/30, 47%, respectively; P=0.2). In tumors with PIK3CA mutation, any IGF1R expression, or loss of PTEN expression, phospho-4EBP1 was more frequently elevated compared with tumors without a known activating event in the PI3K pathway (55/72; 76% vs 3/8, 38%; P=0.033). These findings suggest that activation of the PI3K/Akt pathway via activating mutation of PIK3CA, loss of PTEN, or IGF1R expression have a role in round cell transformation. The PI3K/Akt pathway may therefore provide a therapeutic target in round cell liposarcoma.

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.

An experimental model for the study of well-differentiated and dedifferentiated liposarcoma; deregulation of targetable tyrosine kinase receptors.

Therapeutic progress in well-differentiated/dedifferentiated liposarcoma (WDLPS/DDLPS) is hampered by lack of relevant experimental models, thereby limiting comprehensive molecularly based investigations. Our goal is to bridge this experimental gap by establishing and characterizing an in vitro/in vivo model useful for examining WDLPS/DDLPS molecular pathogenesis and also therapeutic screening and testing. WDLPS/DDLPS cells were isolated from freshly resected human surgical specimens and were phenotypically and molecularly characterized. MDM2 amplification was determined via FISH analysis. Adipogenic differentiation was evaluated using Oil Red O staining and western blotting (WB). Tyrosine kinase receptors' (TKRs) expression in pre-adipocytes, adipocytes, WDLPS, and DDLPS cells was determined via western blot analysis. SCID mouse xenograft growth was assessed after subcutaneous and/or intraperitoneal tumor cell injection. There was enhanced proliferation, migration, invasion, survival, and pro-angiogenic capacity in DDLPS cells vs WDLPS cells. DDLPS cells formed tumors in SCID mice whereas WDLPS did not. WDLPS/DDLPS cells, especially those that exhibited baseline PPARγ expression, partially retained terminal adipogenic differentiation capacity. MDM2 amplification was found in all WDLPS/DDLPS cell strains, CDK4 overexpression was observed in LPS cells as compared with normal adipocytes, and enhanced JUN expression and phosphorylation was seen in DDLPS cells as compared with WDLPS cells. The TKRs: MET, AXL, KIT, and IGF-1R were overexpressed in LPS cells vs normal adipocytes and pre-adipocytes. In conclusion, these newly established cellular and xenograft models can facilitate investigation of liposarcomagenesis, dedifferentiation, and tumor progression. Further studies of the molecular deregulations so identified may lead to improved therapeutic strategies for patients afflicted by these unfavorable malignancies.

Pleomorphic liposarcoma: clinical observations and molecular variables.

BACKGROUND: Pleomorphic liposarcoma (PLS) is a rare high-grade sarcoma that has lipoblastic differentiation. In this study, the authors evaluated PLS natural history, patient outcomes, and commonly deregulated protein biomarkers. METHODS: Medical records from patients (n = 155) who had PLS from 1993 to 2010 were reviewed. Univariate and multivariate analyses were conducted to identify independent prognosticators. A PLS tissue microarray (TMA) (n = 56 patient specimens) was constructed for immunohistochemical analysis of molecular markers, and p53 gene sequencing (exons 5-9) was conducted. RESULTS: The average patient age was 57 years, and the patients presented with primary disease (n = 102), recurrent disease (n = 16), and metastatic disease (n = 37). Lower extremity was the most common disease site (40%), and the average tumor size was 11 cm. Complete follow-up data were available for 83 patients, and their median follow-up was 22.6 months. The 5-year disease-specific survival rate was 53%; and recurrent disease, unresectability, and microscopic positive margins were identified as predictors of a poor prognosis. Systemic relapse (the strongest poor prognostic determinant) developed in 35% of patients with localized PLS. Immunohistochemical analysis revealed increased expression of peroxisome proliferator-activated receptor gamma (an adipogenic marker), B-cell leukemia 2 and survivin (survival factors), vascular endothelial growth factor (an angiogenic factor), matrix metalloproteinase 2, and other biomarkers. Frequent loss of retinoblastoma protein expression and high p53 mutation rates (approximately 60%) were observed. CONCLUSIONS: PLS is an aggressive, metastasizing sarcoma. Identifying ubiquitous molecular events underlying PLS progression is crucial for progress in patient management and outcomes.

Diagnosis, management, and outcome of patients with dedifferentiated liposarcoma systemic metastasis.

BACKGROUND: Dedifferentiated liposarcomas (DDLPSs) result in worse patient outcomes than well-differentiated tumors despite shared molecular derangements. Prevalence and pattern of DDLPS systemic metastases have not been extensively reported; information regarding diagnosis, treatment, and outcomes of metastatic DDLPS patients is limited. Our study seeks to address this knowledge gap. METHODS: Metastatic patients were identified from a clinical database consisting of 277 DDLPS patients treated at the University of Texas M D Anderson Cancer Center (UTMDACC) (1993-2010). Only patients with radiologically demonstrable distant metastases were included. Patient, tumor, treatment, and outcome variables were recorded. Available imaging studies and tumor FFPE blocks were assessed. RESULTS: A total of 40 patients were identified, translating into a DDLPS metastatic rate of 14% (17% for de novo DDLPS and 9% for secondary dedifferentiation). The average patient age was 61 years with a male predilection. The retroperitoneum and lungs were the most common primary and metastatic tumor sites. Any of the 4 described DDLPS morphological subtypes harbored metastatic potential; MFH/UPS-like morphology was the most common. The median time from primary diagnosis to metastasis was 25 months; more than 50% of metastases developed without local failure. The median survival of metastatic patients was 11.5 months; the 5-year DSS was 5.2%. Patients amenable to complete surgical extirpation (n = 14) faired significantly better (P = .001; log rank). CONCLUSIONS: Metastatic spread is an ominous consequence of DDLPS, especially regarding de novo tumors. Occurring relatively early in the course of disease and exhibiting a pulmonary predilection, these lesions are highly aggressive and commonly fatal. Further studies to identify metastatic biomarkers are needed.

A novel HDGF-ALCAM axis promotes the metastasis of Ewing sarcoma via regulating the GTPases signaling pathway.

Ewing sarcoma (ES) is a type of highly aggressive pediatric tumor in bones and soft tissues and its metastatic spread remains the most powerful predictor of poor outcome. We previously identified that the transcription factor hepatoma-derived growth factor (HDGF) promotes ES tumorigenesis. However, the mechanisms underlying ES metastasis remain unclear. Here, we show that HDGF drives ES metastasis in vitro and in vivo, and HDGF reduces metastasis-free survival (MFS) in two independent large cohorts of human ES patients. Integrative analyses of HDGF ChIP-seq and gene expression profiling in ES cells reveal that HDGF regulates multiple metastasis-associated genes, among which activated leukocyte cell adhesion molecule (ALCAM) emerges as a major HDGF target and a novel metastasis-suppressor in ES. HDGF down-regulates ALCAM, induces expression and activation of the downstream effectors Rho-GTPase Rac1 and Cdc42, and promotes actin cytoskeleton remodeling and cell-matrix adhesion. In addition, repression of ALCAM and activation of Rac1 and Cdc42 are required for the pro-metastatic functions of HDGF in vitro. Moreover, analyses in murine models with ES tumor orthotopic implantation and experimental metastasis, as well as in human ES samples, demonstrate the associations among HDGF, ALCAM, and GTPases expression levels. Furthermore, high HDGF/low ALCAM expression define a subgroup of patients harboring the worst MFS. These findings suggest that the HDGF/ALCAM/GTPases axis represents a promising therapeutic target for limiting ES metastasis.

Exosome-transmitted linc00852 associated with receptor tyrosine kinase AXL dysregulates the proliferation and invasion of osteosarcoma.

BACKGROUND: Receptor tyrosine kinase AXL has been found to be highly expressed in osteosarcoma and positively associated with poor prognosis. There are tumor groups with high or low AXL expression, which had different capabilities of invading vessels and forming distal metastases. Exosome-transmitted lncRNA may be transferred intercellularly to promote tumor cells' proliferation and invasion. METHODS: Exosomes were detected by electron microscopy, particle size analysis, and western blotting. High-throughput sequencing helped to find the highest differentially expressed lncRNA in AXL-associated exosomes. Clone formation, wound healing, transwell assay, and xenograft model in nude mice were performed to evaluate cells' proliferation, migration, and invasion in vitro and in vivo. Lentiviral transfection was used to up- or down-regulate the lncRNA levels in cell lines. Luciferase reporter assay and RNA FISH etchelped to indicate the molecular mechanisms. The results in the cell lines were proved in the osteosarcoma tissues with clinical analysis. RESULTS: The exosomes derived from donor cells with high AXL expression could promote the proliferation and invasion and upregulate AXL expression of the receiver cells with low AXL. Linc00852 was the highest differentially expressed lncRNA in AXL-associated exosomes and was also regulated by AXL expression. Although the mechanisms of linc00852 in nucleus were unrevealed, it could upregulate AXL expression partly by competitively binding to miR-7-5p. The AXL-exosome-linc00852-AXL positive feedback loop might exist between the donor cells and the receiver cells. Clinically, linc00852 was significantly highly expressed in osteosarcoma tissues and positively associated with tumor volumes and metastases, which was also obviously related with AXL mRNA expression. CONCLUSION: AXL-associated exosomal linc00852 up-regulated the proliferation, migration, and invasion of osteosarcoma cells, which would be considered as a new tumor biomarker and a special therapeutic target for osteosarcoma.

Dysregulation of heat shock protein 27 expression in oral tongue squamous cell carcinoma.

BACKGROUND: Recent proteomic studies identified Hsp27 as a highly over-expressed protein in oral squamous cell carcinoma (OSCC). Clinical studies that attempted to evaluate the prognostic values of Hsp27 yielded inconsistent results, which may be due to inclusion of OSCC cases from multiple anatomic sites. In this study, to determine the utility of Hsp27 for prognosis, we focused on oral tongue SCC (OTSCC), one of the most aggressive forms of OSCC. METHODS: Archival clinical samples of 15 normal oral tongue mucosa, 31 dysplastic lesions, 80 primary OTSCC, and 32 lymph node metastases were examined for Hsp27 expression by immunohistochemistry (IHC). Statistical analyses were carried out to assess the prognostic value of Hsp27 expression for patients with this disease. RESULTS: Dysregulation of Hsp27 expression was observed in dysplastic lesions, primary OTSCC, and lymph node metastases, and appears to be associated with disease progression. Statistical analysis revealed that the reduced Hsp27 expression in primary tumor tissue was associated with poor differentiation. Furthermore, the higher expression of Hsp27 was correlated with better overall survival. CONCLUSION: Our study confirmed that the dysregulation of Hsp27 expression is a frequent event during the progression of OTSCC. The expression of Hsp27 appears to be an independent prognostic marker for patients with this disease.

Proteomic based identification of manganese superoxide dismutase 2 (SOD2) as a metastasis marker for oral squamous cell carcinoma.

Metastasis is a critical event in oral squamous cell carcinoma (OSCC) progression. To identify proteomic biomarkers for OSCC metastasis, 3 paired OSCC cell lines (UM1/UM2, 1386Tu/1386Ln, 686Tu/686Ln) with different metastatic potential were examined. Among those 3 cell lines, UM1, 1386Ln and 686Ln exhibited a higher degree of metastatic potential than their paired cell lines UM2, 1386Tu and 686Tu, respectively, as measured using an in vitro cell invasion assay. A total of 40 differentially expressed proteins were identified using 2D-PAGE/MS proteomic approach. Selected protein candidates (superoxide dismutase 2 and heat shock protein 27) were further investigated by immuno-histochemistry (IHC) method using independent OSCC patient tissue samples. The statistically significantly increases in IHC staining for manganese superoxide dismutase 2 (SOD2) were observed in lymph node metastatic disease when compared with the paired primary OSCC. Our results thus indicated that elevated SOD2 levels is associated with lymph node metastasis in OSCC and may provide predictive values for diagnosis of metastasis.

T-cell lymphoma with rhabdomyolysis: case report and literature review.

Rhabdomyolysis refers to the destruction or disintegration of striated muscles. This syndrome is characterized by muscle breakdown and necrosis, resulting in the leakage of intracellular muscle constituents into the circulation and extracellular fluid. We report a rare case of rhabdomyolysis complicating multi-organ failure caused by T-cell lymphoma in a 32-year-old woman. The final diagnosis was rhabdomyolysis caused by peripheral T-cell lymphoma based on bone marrow aspirate and biopsy.

[Expression of syndecan-1 at different stages in the course of gastric carcinoma and its significance].

OBJECTIVE: To investigate the expression of syndecan-1 protein at different stages in the course of gastric carcinoma and its significance in carcinogenesis and metastasis. METHODS: There were 56 cases of chronic gastritis, 50 cases of chronic atrophic gastritis, 59 cases of intestinal metaplasia, 61 cases of displasia, and 112 cases of gastric carcinoma. Among the carcinoma cases, 55 were without and 57 with lymph node metastases. All paraffin-embedded tissue samples were assessed by immunohistochemistry. RESULTS: The syndecan-1 positive rate was 96.43% (54/56) in gastritis, 98.00% (49/50) in chronic atrophic gastritis, 100.00% (59/59) in intestinal metaplasia, 91.80% (56/61) in displasia, 45.45% (25/55) in gastric carcinoma without, and 24.56% (14/57) in gastric carcinoma with lymph node metastases. There was no significant difference among chronic gastritis, chronic atrophic gastritis and intestinal metaplasia (P > 0.05). There was a significant difference between displasia group and gastric carcinoma group (P <0.05), as well as between gastric carcinoma with and without lymph node metastases. There was a significant difference among well, moderately and poorly differentiated carcinoma groups. CONCLUSION: A decreasing expression of syedecan-1 in the development of gastric carcinoma is related with gastric carcinogenesis, and it may further promote metastasis of gastric carcinoma.

[Suppression of osteosarcoma in vitro by coexpression of antisense VEGF165 cDNA and thymidine kinase gene].

OBJECTIVE: To investigate the effect of VEGF expression in osteosarcoma cell line and the target killing effect of HSV1-TK/GCV system on transfected osteosarcoma cells under hypoxia conditions. METHODS: Eukaryotic expression plasmid with HRE promoter was constructed to express the antisense VEGF165 cDNA and Hygromycin phospho-transferase-thymidine kinase (HyTK) fusion gene. The recombinant vectors were then transfected into osteosarcoma cell line MG63 with lipofectin mediated gene transfer methods. PCR and RT-PCR were used to confirm the presence and expression of TK gene. The sensitivity of transfected cells to GCV and "bystander effect (BSE)" of HSV1-TK/GCV system under normoxia or hypoxia conditions were measured by MTT assay and mixed co-culture experiment. The expression of VEGF protein was detected by ELISA under hypoxia condition. Cell cycle phase distribution was determined by flow cytometry. In addition, electromicroscopy was used to document ultrastructural alterations. RESULTS: The eukaryotic expression vector pBI-HRE-AsVEGF165 -HyTK was constructed successfully. The transfected cell line MG63TV was established and confirmed by PCR and RT-PCR of the presence of transgene and its mRNA expression. GCV was toxic to transfected cells in a concentration-dependent manner. The sensitivity to GCV toxicity was 100 times higher under hypoxia condition than that under normoxic condition. The mixed culture experiments showed that the "bystander effect" was enhanced significantly under hypoxia condition. VEGF expression of transgene cells under hypoxia condition decreased 50% compared to that of normal condition. Under hypoxia and GCV, DNA synthesis of MG63TV cells was inhibited along with an increase of cells at G0 approximately G1 phase, apoptosis and necrosis. CONCLUSIONS: Antisense VEGF expression driven by HRE promoter in combination with hypoxia can provide a target inhibition of VEGF expression in human osteosarcoma cells, with an enhanced selective killing effect and BSE of the HSV-TK/GCV system. The double-gene co-expression system in study provides experimental basis for therapy against osteosarcoma by a synchronous antiangiogenic and suicide gene approach.

lncRNA DANCR promotes tumor progression and cancer stemness features in osteosarcoma by upregulating AXL via miR-33a-5p inhibition.

lncRNAs regulate the initiation and progression of osteosarcoma, although the mechanism by which this occurs remains unknown. The present study shows that over-expression of the lncRNA DANCR increased osteosarcoma cell proliferation, migration, and invasion in vitro, as well as promoted xenograft tumor growth and lung metastasis in vivo. Mechanistically, DANCR promoted osteosarcoma progression by mediating cancer stem cells (CSCs) features. Moreover, pull-down assays and luciferase reporter assays indicated that DANCR upregulated expression of the receptor tyrosine kinase AXL by competitively binding to miR-33a-5p. Furthermore, DANCR enhanced the expression of proteins downstream of the AXL-Akt pathway. DANCR was consistently significantly increased in osteosarcoma tissues, and its expression was positively correlated with tumor size and metastasis as an independent poor prognostic factor. Furthermore, both in patient tumors and xenograft tumors, DANCR expression was positively related to AXL and negatively related to miR-33a-5p. Taken together, our results suggest that DANCR is a crucial upregulator of osteosarcoma and an independent predictor of prognosis. DANCR increases CSCs function by upregulating AXL via competitively binding to miR-33a-5p, and this function is sequentially performed through the PI3K-Akt signaling pathway.

[Expression of microvessel density in multistep tissues of gastric carcinoma and significance thereof].

OBJECTIVE: To investigate the expression of microvessel density (MVD) in multistep tissue of gastric carcinoma and CD34 in the multistep tissue of gastric carcinogens. METHODS: 277 specimens of gastric diseases, 56 specimens of chronic gastritis, 50 specimens of chronic atrophic gastritis, 59 specimens of intestinal metaplasia, 61 specimens of dysplasia, 57 specimens of gastric carcinoma with lymph node metastases, and 55 specimens of gastric carcinoma without lymph node metastases, obtained from pathological department, Sun Yat-sen university, underwent pathological examination and immunohistochemistry to detect the expression of CD34 antigen that is expressed only in the endothelial cells in tumor. RESULTS: The mean MVD was 13 +/- 10 in the specimens of chronic gastritis, 11 +/- 7 in the chronic atrophic gastritis group, 13 +/- 9 in the intestinal metaplasia group, 17 +/- 10 in the dysplasia group, 27 +/- 11 in the gastric carcinoma without lymph node metastases group, and 28 +/- 10 in the gastric carcinoma with lymph node metastases group. There were not significant differences in MVD among the chronic gastritis group, chronic atrophic gastritis group, and intestinal metaplasia group (all P > 0.05), there was a significant difference in MVD between the chronic gastritis group and dysplasia group (P < 0.05). In the specimens of gastric carcinoma, there were no significant difference in MVD between those with and without lymph node metastases (P > 0.05), and between those of high and low differentiation degrees (both P < 0.05). CONCLUSION: The increase of expression of CD34 in the multistage tissues of gastric carcinoma is associated with the genesis of gastric cancer, and not be related to the gastric carcinoma metastases.