SQLE is a promising prognostic and immunological biomarker and correlated with immune Infiltration in Sarcoma.

Squalene epoxidase (SQLE) is an essential enzyme involved in cholesterol biosynthesis. However, its role in sarcoma and its correlation with immune infiltration remains unclear. All original data were downloaded from The Cancer Genome Atlas (TCGA). SQLE expression was explored using the TCGA database, and correlations between SQLE and cancer immune characteristics were analyzed via the TISIDB databases. Generally, SQLE is predominantly overexpressed and has diagnostic and prognostic value in sarcoma. Upregulated SQLE was associated with poorer overall survival, poorer disease-specific survival, and tumor multifocality in sarcoma. Mechanistically, we identified a hub gene that included a total of 82 SQLE-related genes, which were tightly associated with histone modification pathways in sarcoma patients. SQLE expression was negatively correlated with infiltrating levels of dendritic cells and plasmacytoid dendritic cells and positively correlated with Th2 cells. SQLE expression was negatively correlated with the expression of chemokines (CCL19 and CX3CL1) and chemokine receptors (CCR2 and CCR7) in sarcoma. In conclusion, SQLE may be used as a prognostic biomarker for determining prognosis and immune infiltration in sarcoma.

miR-27b attenuates dexamethasone-inhibited proliferation and osteoblastic differentiation in MC3T3-E1 cells by targeting PPARγ2.

Osteoporosis is a metabolic bone illness characterized by low bone density and a high risk of fracture. It is estimated that there are >60 million individuals in China suffering from this disease, which highlights an urgent requirement for the development of novel and safe drugs for the long-term treatment of osteoporosis. MicroRNAs (miRNAs/miRs) have previously been identified as critical regulators in the progression of osteoporosis. As an intronic miRNA, miR-27b enhances the osteoblastic differentiation of stem cells from the bone marrow and the maxillary sinus membrane. However, the mechanism underlying miR-27b in osteoporosis remains to be elucidated. In the present study, MC3T3-E1 pre-osteoblasts were treated with dexamethasone (DEX) to establish an in vitro model of osteoporosis. The results of the present study demonstrated that DEX treatment markedly inhibited the viability of MC3T3-E1 cells, and downregulated the expression level of miR-27b. The results of reverse transcription-quantitative PCR, western blotting and dual-luciferase assays revealed that miR-27b directly regulated and suppressed the expression of peroxisome proliferator-activated receptor γ2 (PPARγ2) in MC3T3-E1 cells. Furthermore, overexpression of miR-27b by transfection of cells with miR-27b mimic attenuated DEX-mediated inhibition of cell viability, alkaline phosphatase (ALP) activity and the expression levels of bone morphogenetic protein-2 (BMP2), runt-related protein 2 (Runx2) and osteocalcin (OCN). The results of the present study indicated that miR-27b alleviated DEX-inhibited proliferation and osteoblastic differentiation. Moreover, miR-27b knockdown repressed MC3T3-E1 cell viability, ALP activity and protein levels of BMP2, Runx2 and OCN. However, these effects were abrogated by small interfering RNA-mediated PPARγ2 silencing. In conclusion, the results of the present study demonstrated that miR-27b attenuated DEX-inhibited proliferation and osteoblastic differentiation in MC3T3-E1 pre-osteoblasts by targeting PPARγ2.

Tripartite Motif Containing 52 Positively Regulates NF-κB Signaling by Promoting IκBα Ubiquitination in Lipopolysaccharide-Treated Microglial Cell Activation.

BACKGROUND Microglial cell activation is the first response to spinal cord injury (SCI). The purpose of the study was to investigate the role and mechanism of tripartite motif containing 52 (TRIM52) in microglial cell activation and the inflammatory response. MATERIAL AND METHODS The cerebral cortex was isolated in rats, and primary microglial cells were subsequently incubated for 7 to 9 days and activated by lipopolysaccharide (LPS). TRIM52 overexpression and interference lentivirus were constructed, and primary microglial cells were transfected. Cytokine levels of interleukin-1ß and tumor necrosis factor-a were detected using enzyme-linked immunosorbent assay kits. TRIM52 mRNA expression and protein levels were examined by real-time polymerase chain reaction and nuclear factor-kappa B (NF-kappaB) and inhibitory kappa B-alpha (IkappaBalpha) protein expression were examined by western blot. The interaction between TRIM52 and IkappaBalpha was analyzed by co-immunoprecipitation (Co-IP) detection. Microglial marker Iba-1 and microglial cell activation marker OX-42 were detected by immunofluorescent staining. RESULTS Primary rat microglial cells were successfully isolated and activated by LPS. The expression levels of cytokines and TRIM52 and nuclear accumulation of NF-kappaB in microglial cells all increased in a dose-dependent manner with LPS. Cytokine and nuclear NF-kappaB levels decreased after TRIM52 knockdown, while the opposite expression pattern was found in microglial cells transfected with TRIM52 gene overexpression lentivirus. Co-IP revealed the association between TRIM52 and IkappaBalpha, and overexpressed TRIM52 promoted the ubiquitination of IkappaBalpha and significantly reduced its protein expression. CONCLUSIONS TRIM52 activated the NF-kappaB signaling pathway by promoting IkappaBalpha ubiquitination, thereby regulating LPS-induced microglial cell activation and the inflammatory response.

SIRT 1 Overexpression is Associated with Metastasis of Pancreatic Ductal Adenocarcinoma (PDAC) and Promotes Migration and Growth of PDAC Cells.

BACKGROUND SIRT 1, as a class III histone deacetylase (HDAC), is implicated in the initiation and progression of malignancies. However, the association of SIRT 1 with tumorigenesis or progression of pancreatic ductal adenocarcinoma (PDAC) is not clear. MATERIAL AND METHODS In our study we investigated SIRT 1 expression in PDAC samples and evaluated the association of SIRT 1 level with the clinical and pathological characteristics of PDAC patients. We investigated the role of SIRT 1 in the migration and growth of PDAC PANC-1 or BxPC-3 cells using gain-of-function and loss-of-function approach. RESULTS We demonstrated that SIRT 1 mRNA level was significantly promoted in intra-tumor tissues compared to peri-tumor tissues of PDAC; and SIRT 1 overexpression was markedly associated with distant or lymph node (LN) metastasis of these PDAC tissues. Moreover, the in vitro wound healing assay demonstrated that SIRT 1 overexpression with lentivirus vector markedly promoted the migration of PANC-1 or BxPC-3 cells, whereas SIRT 1 knockdown using SIRT 1 specific siRNA transfection significantly inhibited the migration of PDAC cells. The colony forming assay confirmed SIRT 1 promotion of the growth of PANC-1 or BxPC-3 cells. CONCLUSIONS In summary, SIRT 1 overexpression is significantly associated with metastasis of PDAC, and overexpressed SIRT 1 plays an important role in pancreatic cancer cell migration and growth. Our data warrants further studies on SIRT 1 as a novel chemotherapeutic target in PDAC.

Mechano-growth factor accelerates the proliferation and osteogenic differentiation of rabbit mesenchymal stem cells through the PI3K/AKT pathway.

BACKGROUND: Mesenchymal stem cells (MSCs) can differentiate into chondroblasts, adipocytes, or osteoblasts under appropriate stimulation. Mechano-growth factor (MGF) reportedly displays a neuroprotective effect in cerebral regions that were exposed to ischemia and is expressed in stromal cells of the eutopic endometrium and in glandular cells of the ectopic endometrium. RESULTS: This study sought to understand the potential involvement of phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) in MGF-induced growth of rabbit MSCs (rMSCs). We applied various concentrations of MGF to cultured rMSCs and observed the growth rate of the cells, the changes in the phosphorylation state of AKT and mammalian target of rapamycin (mTOR), and the expression levels of alkaline phosphatase and osteocalcin. We found that the growth and osteogenic differentiation of MGF-induced rMSCs were promoted primarily by phosphorylated AKT, and that this phosphorylation, as well mTOR phosphorylation, was mediated by the MGF receptor. CONCLUSION: Our study suggests that MGF promotes the growth and osteogenic differentiation of rMSCs primarily through the PI3K/AKT pathway.

miR-155 inhibitor reduces the proliferation and migration in osteosarcoma MG-63 cells.

As the most common malignant primary bone tumor in childhood, osteosarcoma (OS) maintains a high recurrence, despite the significant improvements in the overall survival rate of high-grade OS patients during the recent decades. Therefore, a novel therapy strategy is required for OS treatment. Recently, various microRNAs (miRNAs or miRs) have been confirmed as deregulated in OS, and the miR-155 dysregulation in OS has been discovered by the microarray analysis. In the present study, the regulation of miR-155 on the OS cell proliferation, migration and invasion on the MG-63 cells was explored in vitro. The miR-155 mimics were found to promote cell proliferation, colony formation, migration and invasion significantly, compared to the control miRNA. An miR-155 inhibitor was also used to evaluate whether miR-155 served as a therapeutic target for OS. The results demonstrated that the miR-155 inhibitor significantly reduced the proliferation, colony formation, migration and invasion of the MG-63 OS cells. Thus, the study confirmed the oncogenic regulation on the OS progression of miR-155, which could serve as a therapeutic target with an miR-155 inhibitor.

[Effect of Epimedium extract on osteoprotegerin and RANKL mRNA expressions in glucocorticoid-induced femoral head necrosis in rats].

OBJECTIVE: To investigate the effect of glucocorticoid on the expression levels of osteoprotegerin (OPG) and receptor activator of nuclear factor kappa B ligand (RANKL) mRNAs in rat femoral head and the antagonistic effect of Epimedium, and explore the mechanism of Epimedium in preventing glucocorticoid-induced femoral head necrosis. METHODS: Forty-eight adult SD rats were randomized into glucocorticoid group, Epimedium group and control group. In the former two groups, the rats received intramuscular injection of 12.5 mg prednisolone twice a week, and in Epimedium group, additional 1 ml/100 g aqueous Epimedium extract (equivalent to 0.1 g/ml of the crude drug) was administered intragastrically once daily. The control group received only intramuscular saline injection. After 4 weeks of treatment, osteonecrosis of the left femoral head was detected by HE staining, and the right femoral head was sampled for detection of OPG and RANKL mRNA expressions using real-time quantitative PCR. RESULTS: In glucocorticoid, Epimedium and control groups, the mortality rate of the rats was 12.5% (2/16), 6.25% (1/16), 0 (0/16), and femoral head necrosis occurred at a rate of 71.43% (10/14), 26.67% (4/15), and 0 (0/16), respectively. In glucocorticoid group, the expression level of OPG mRNA was significantly lower, RANKL expression significantly higher, and OPG/RANKL ratio significantly lower than those in Epimedium and control groups (P<0.05). OPG, RANKL and their ratios showed no significant differences between Epimedium group and the control group. CONCLUSION: Epimedium can prevent glucocorticoid-induced femoral head necrosis probably by antagonizing glucocorticiod-induced abnormal expressions of OPG and RANKL mRNA.