GINS2 was regulated by lncRNA XIST/miR-23a-3p to mediate proliferation and apoptosis in A375 cells.

Melanoma ranks second in aggressive tumors, and the occurrence of metastasis in melanoma results in a persistent drop in the survival rate of patients. Therefore, it is very necessary to find a novel therapeutic method for treating melanoma. It has been reported that lncRNA XIST could promote the tumorigenesis of melanoma. However, the mechanism by which lncRNA XIST regulates the progression of melanoma remains unclear. The proliferation of A375 cells was measured by clonal formation. Cell viability was detected by MTT assay. Flow cytometry was performed to detect cell apoptosis and cycle. The level of GINS2, miR-23a-3p, and lncRNA XIST was investigated by qRT-PCR. Protein level was detected by Western blot, and the correctness of prediction results was confirmed by Dual luciferase. In present study, GINS2 and lncRNA XIST were overexpressed in melanoma, while miR-23a-3p was downregulated. Silencing of GINS2 or overexpression of miR-23a-3p reversed cell growth and promoted apoptosis in A375 cells. Mechanically, miR-23a-3p directly targeted GINS2, and XIST regulated GINS2 level though mediated miR-23a-3p. Moreover, XIST exerted its function on cell proliferation, cell viability, and promoted the cell apoptosis of A375 cells though miR-23a-3p/GINS2 axis. LncRNA XIST significantly promoted the tumorigenesis of melanoma via sponging miR-23a-3p and indirectly targeting GINS2, which can be a potential new target for treating melanoma.

MiR-291a-3p regulates the BMSCs differentiation via targeting DKK1 in dexamethasone-induced osteoporosis.

Osteoporosis is a skeleton disease affecting 55% of people over age 60, and the number is still increasing due to an ageing population. One method to prevent osteoporosis is to increase the formation of new bone while preventing the resorption of older bone. Thus, osteogenic differentiation of bone marrow-derived mesenchymal stem cells (BMSCs) is of great importance in improving the treatment of osteoporosis. On the other hand, glucocorticoids (GCs) are widely used to treat the chronic inflammatory disorders, but long-term exposure to GCs can induce osteoporosis. In present study, we treated BMSCs with dexamethasone (DEX) to simulate GC-induced osteoporosis. MTT assay, ALP activity, and Alizarin Red were used to evaluate the role miRNA-291a-3p in the DEX-induced osteogenic differentiation suppression. Further, we used qPCR and western blot to investigate the mechanisms of miRNA-291a-3p affecting BMSCs differentiation. The results showed that miRNA-291a-3p could improve the cell viability, osteogenic differentiation, and ALP activity, which are suppressed by DEX in BMSCs. Furthermore, we found that the osteogenesis genes Runx2, DMP1, and ALP were upregulated whereas the lipogenic genes C/EBPα and PPARγ were downregulated when miRNA-291a-3p mimics were transfected. Additionally, we demonstrated that miRNA-291a-3p promoted BMSCs' osteogenic differentiation by directly suppressing DKK1 mRNA and protein expression and subsequently activating Wnt/ß-catenin signaling pathway. Our study suggests that miR-291a-3p plays an important role in preventing osteoporosis and may serve as a potential miRNA osteoporosis biomarker.

Notch1-ADAM8 positive feed-back loop regulates the degradation of chondrogenic extracellular matrix and osteoarthritis progression.

BACKGROUND: Osteoarthritis (OA) is one of the most prevalent joint disease, and there are still no effective therapeutic agents or clinical methods for the cure of this disease to date. The degradation of cartilage extracellular matrix (ECM) is a major cause of OA. METHOD: IL-1ß was used to induce chondrogenic degradation. Q-PCR and Western blotting were used to detect mRNA and protein level, respectively. ELISA was used to detect the secreted TNF-α and IL-6 level. Immunofluorescence was used to detect the protein level of Aggrecan, Collagen II and ki67. TUNEL and flow cytometry were used to examine cell apoptosis of chondrocytes. ChIP and luciferase assay were used to study molecular gene regulation. Osteoarthritic animal model and Safranin-O staining were used to determine the in vivo OA phenotype. RESULTS: The expression of ADAM8 was up-regulated in osteoarthritic chondrocytes. Knockdown of ADAM8 suppressed the OA phenotype in the in vitro OA cell model. ADAM8 regulated OA progression through the activation of EGFR/ERK/NF-κB signaling pathway. Inhibition of Notch signaling suppressed OA phenotype in the in vitro OA cell model. Notch signaling regulated the gene expression of ADAM8 directly via Hes1. Notch1-ADAM8 positive feedback loop promoted the progression of OA in vivo. CONCLUSION: Notch1-ADAM8 feed-back loop regulates the degradation of chondrogenic extracellular matrix and osteoarthritis progression.

ADAM8 promotes chondrosarcoma cell migration and invasion by activating the NF-κB/MMP-13 signaling axis.

ADAM8 is reported to promote extracellular matrix degradation to provide conditions for tumor metastasis. However, the underlying mechanism of ADAM8 in modulating chondrosarcoma (CHS) metastasis remains unclear. We used two human CHS cell lines SW1353 and HCS-2/8 to analyze the expression profiles of ADAM8 in CHS cells compared with the normal chondrocytes. An important proteolytic enzyme MMP-13 was detected as a marker for extracellular matrix degradation in chondrocytes. Then, by silencing or overexpressing ADAM8, the effects on cell migration and invasion in SW1353 and HCS-2/8, and the downstream signal transduction pathways were evaluated. ADAM8 and MMP-13 were highly expressed, and the NF-κB pathway was activated in SW1353 and HCS-2/8 cells. Silencing ADAM8 significantly reduced the ability of cell migration and invasion, and blocked the NF-κB signaling pathway through IκBα and p65 dephosphorylation, leading to reduced NF-κB transcription activity and decreased MMP-13 expression. ADAM8 overexpression promoted these processes, which, however, were reversed by an inhibitor Bay 11-7085. Our data showed a novel regulation mechanism for ADAM8 in promoting CHS migration and invasion by activating the NF-κB/MMP-13 signaling axis. Modulation of their levels may serve as potential targets in the treatment of CHS and even other cartilage diseases.

Roles of Signaling Pathways in the Epithelial-Mesenchymal Transition in Cancer.

The epithelial-mesenchymal transition (EMT) is a cellular process though which an epithelial phenotype can be converted into a phenotype of mesenchymal cells. Under physiological conditions EMT is important for embryogenesis, organ development, wound repair and tissue remodeling. However, EMT may also be activated under pathologic conditions, especially in carcinogenesis and metastatic progression. Major signaling pathways involved in EMT include transforming growth factor ß(TGF-ß), Wnt, Notch, Hedgehog and other signaling pathways. These pathways are related to several transcription factors, including Twist, Smads and zinc finger proteins snail and slug. These interact with each other to provide crosstalk between the relevant signaling pathways. This review lays emphasis on studying the relationship between EMT and signaling pathways in carcinogenesis and metastatic progression.

[Study of apoptosis related factors regulatory mechanism of resveratrol to human skin squamous cell carcinoma A431 xenograft in nude mice].

OBJECTIVE: To explore the anti-tumor effects of resveratrol (Res) upon human skin squamous cell carcinoma A431 xenograft in nude mice and elucidate the regulatory mechanisms of survivin and caspase-3. METHODS: The model of human skin squamous cell carcinoma (A431) xenograft in nude mice was established. And the animals were randomly divided into saline-negative control, cyclophosphamide (CTX) positive control, Res high-, medium- and low-dosage and blank control groups (n = 10 each). After drug intervention, tumor-bearing mice were sacrificed. The tumor growth curve was plotted and the Res inhibition rate calculated by terminal tumor weight. The morphological changes of tumor cell among groups were observed by hematoxylin and eosin staining; cell apoptosis was detected by terminal deoxynucleotidyl transferase dUTP nick end labeling TUNEL; the impact of Res upon the protein expressions of survivin and caspase-3 in tumor issues was observed by Western blot. Analysis of variance and Pearson's correlation were employed for statistical analyses. RESULTS: (1) By the end of treatment, the tumor volume of CTX, Res high-, medium-, low-dosage, saline-negative control and blank control groups were (1154 ± 255), (1002 ± 115), (1207 ± 176), (1342 ± 211), (1642 ± 226), (1564 ± 156) mm(3) respectively, and tumor weight of CTX, Res high-, medium-, low-dosage, saline-negative control and blank control groups (1.84 ± 0.30), (1.72 ± 0.39), (1.96 ± 0.40), (2.67 ± 0.73), (3.16 ± 0.52), (3.33 ± 0.59) g respectively. Through analysis of variance, the tumor volume and weight of Res high-, medium-, low-dosage groups were smaller than those of saline-negative control and blank control groups (all P < 0.05). The inhibition rate of Res high-, medium- and low-dosage groups were 45.57%, 37.97% and 15.51% respectively. (2) The apoptosis index of the above groups were 36.79% ± 8.86%, 33.15% ± 6.00%, 18.09% ± 3.92%, 10.53% ± 4.20%, 3.87% ± 1.63%, 2.73% ± 1.61%. Through analysis of variance, the apoptosis index of Res groups were higher than those of saline-negative control and blank control groups (all P < 0.05). (3) The protein expression of survivin/ß-actin of each group were 0.48 ± 0.20, 0.19 ± 0.11, 0.22 ± 0.12, 0.28 ± 0.24, 0.98 ± 0.41, 0.85 ± 0.34. The protein expression of caspase-3/ß-actin of each group were 0.42 ± 0.09, 0.31 ± 0.10, 0.31 ± 0.07, 0.22 ± 0.08, 0.14 ± 0.04, 0.13 ± 0.05 respectively. Through analysis of variance, the protein expression of survivin of Res groups was lower than those of the saline-negative control and blank control groups (all P < 0.05). And the protein expression of caspase-3 of Res groups were higher than those of the saline-negative control and blank control group (all P < 0.05). Through Pearson's analysis, the protein expression of survivin and caspase-3 had no correlation (r = -0.279, P > 0.05). CONCLUSIONS: Res inhibits the growth of human skin squamous cell carcinoma A431 xenograft in nude mice. And its mechanism may be associated with the apoptosis of tumor cell through the depression of survivin and the activation of caspase-3.

Reduced expression of Raf kinase inhibitor protein correlates with poor prognosis in pancreatic cancer.

AIM: Raf kinase inhibitory protein (RKIP) is an inhibitor of the Raf/MEK/MAP kinase signaling cascade and a suppressor of cancer metastasis. But its function in pancreatic cancer was not yet clarified completely. The aim of this study was to investigate the involvement of RKIP in pancreatic cancer. METHODS: RKIP expression was investigated retrospectively by immunohistochemistry in paraffin-embedded primary tumor tissue samples from a series (n = 99) of consecutive patients with pancreatic cancer. Survival was calculated using Kaplan-Meier curves. Parameters found to be of prognostic significance in univariate analysis were verified in a multivariate Cox regression model. RESULTS: RKIP expression was high in normal pancreatic epithelium and retained to varying degrees in pancreatic cancer tissues. However, in tumor tissues with lymph node metastasis (P = 0.008) and high UICC stage (P = 0.006), RKIP expression was highly significantly reduced or lost. Furthermore, the reduced expression of RKIP significantly correlated with both poor overall and disease-free survival (P = 0.008 and 0.01, respectively). Multivariate analyses revealed RKIP to be an independent prognosticator. CONCLUSION: These findings suggest that RKIP could be a promising marker for predicting a better prognosis in pancreatic cancer.

NDRG2 down-regulation and CD24 up-regulation promote tumor aggravation and poor survival in patients with gallbladder carcinoma.

Recent studies have demonstrated that N-Myc downstream-regulated gene 2 (NDRG2) may reduce the metastatic potential of breast cancer and hepatocellular carcinoma cells by regulating the expression of CD24, which is expressed in a large variety of solid tumors. The aim of this study was to clarify the clinical value of NDRG2 and CD24 expression in primary gallbladder carcinoma (GBC). One hundred and thirty GBC tissues were evaluated by immunohistochemistry for NDRG2 and CD24 expression. The associations of NDRG2 and CD24 expression with the clinicopathological characteristics and the overall survival of patients with GBC were analyzed. NDRG2 and CD24 were positively expressed in 49/130 (37.69%) and 107/130 (82.31%) of GBC tissues, respectively. In addition, the tumors with the down-regulation of NDRG2 and the up-regulation of CD24 more frequently had lymph node metastasis and lymphovascular invasion. Moreover, the tumors with the down-regulation of NDRG2 and the up-regulation of CD24 tended to show deeper invasion depth and higher TNM stage. There was a negative correlation between NDRG2 expression and CD24 expression in GBC tissues (r = -0.86, P < 0.001). The patients with NDRG2 negative expression correlated with poor prognosis of GBC (P = 0.01), as opposed to CD24 (P = 0.01). The survival rate of the patients with NDRG2-/CD24+ expression was the lowest (P < 0.001), and conjoined expression of NDRG2-/CD24+ was an independent prognostic indicator of GBC (P = 0.003). Our data suggest that NDRG2 down-regulation or CD24 up-regulation is an important feature of GBC. A combined detection of NDRG2/CD24 co-expression may benefit us in prediction of the prognosis in GBC.