[Involvement of miR-34a and p53 protein of cerebral cortex in electroacpuncture analgesia in mice with neuropathic pain].

OBJECTIVE: To explore the involvement of miR-34a in cerebral cortex mediated anti-hyperalgesic effect of electroacupuncture (EA) in mice with neuropathic pain induced by chronic constriction injury (CCI) of sciatic nerve, so as to reveal its mechanisms underlying improvement of neuropathic pain. METHODS: A total of 75 male C57BL/6 mice were equally randomized into 3 groups: sham, CCI model and CCI+EA (n=25 in each group). Mice of the sham group received simple separation of the right sciatic nerve without ligation. The CCI model was established by liagation of the right sciatic nerve. EA (2 Hz /15 Hz, 1 mA) was applied to bilateral "Zusanli" (ST36) and "Sanyinjiao" (SP9) for 30 min, once every other day. The mechanical and thermal pain threshold of the bilateral hind-paws was detected at the 3rd, 5th and 7th day after modeling, and the expression of miR-34a of bilateral cerebral cortex tissues and that of p53 protein of the left cerebral cortex were determined by using quantitive real time PCR and Western blot, respectively. RESULTS: The mechnical paw withdrawal frequency were significantly higher and the thermal paw withdrawal latencies (PWLs) were significantly shorter at the affected hind-limb (rather than at the healthy hind limb) on day 3, 5 and 7 in the CCI model group than those in the sham group (P<0.05), and considerably reversed at the affected hind-limb (rather than at the healthy hind limb) in the EA group than in the CCI model group (P<0.05), suggesting an analgesic effect of EA intervention. After modeling, the expression levels of miR-34a and p53 on day 3, 5 and 7 were significantly up-regulated in the left cerebral cortex tissue (rather than in the right cerebral cortex) of the CCI model group in comparison with the sham group (P<0.05). After EA intervention, the up-regulated expression levels of miR-34a and p53 in the left cerebral cortex tissue (rather than in the right cerebral cortex) were obviously suppressed in the EA group relevant to the CCI model group (P<0.05). CONCLUSION: EA stimulation of ST36 and SP9 can down-regulate the expression of miR-34a and p53 in the contra-lateral cerebral cortex tissue of the CCI mice, which may contribute to its anti-hyperalgesic effect.

Prognostic Value of miR-375 for Survival Outcomes in Various Cancers: A Systematic Review and Meta-Analysis.

BACKGROUND: miR-375 plays a role in tumor progression; however, its potential as a prognostic factor in cancer remains unclear. This meta-analysis assessed the value of miR-375 as a global prognostic biomarker in human cancer. METHODS: A systematic literature review was performed to retrieve publications with relevant survival data. Pooled hazard ratios (HRs) were calculated for low miR-375 expression. Publication bias was examined. RESULTS: Data were extracted from 11 studies of 1,797 patients (low expression in 769 cases; high in 1,028 cases). The pooled HR for overall/cumulative survival (OS/CS) was 1.90 (95% confidence interval (CI) 1.57-2.29) and the pooled HR for disease-free, recurrence-free or progression-free survival (DFS/RFS/PFS) was 1.93 (95% CI 1.39-2.67), indicating low miR-375 expression was associated with significantly poorer outcomes compared to normal/high miR-375 expression. Subgroup analysis revealed miR-375 might be a good prognostic factor in cancer, regardless of population, sample type, and cancer type. The prognostic value of miR-375 in non-Chinese patients was particularly high (pooled HR > 2). CONCLUSION: Low miR-375 expression could represent a valuable prognostic marker in various cancers. Circulating miR-375 levels may provide a useful non-invasive, practical prognostic biomarker. However, the prognostic value of miR-375 in specific cancer types remains unclear; further studies are warranted.

Fructose-1,6-bisphosphatase is a novel regulator of Wnt/ß-Catenin pathway in breast cancer.

Fructose-1,6-bisphosphatase (FBP1), the rate-limiting enzyme in gluconeogenesis, is a tumor suppressor that frequently down-regulated in cancers, especially breast cancer. Here, we provide both supporting and contradicting evidences about the expression pattern and function of FBP1 in breast cancer. Data mining of Oncomine database showed that FBP1 is commonly up-regulated in tumor tissues compared with non-tumor tissues regardless of histological type. Analysis of a large-scale cohort derived from Kaplan-Meier Plotter showed that lower FBP1 expression associated with poor clinical outcome. Genetic silencing of FBP1 reduced aerobic glycolysis and the malignant potential of breast cancer cells. Gene set enrichment analysis (GSEA) of the expression profiles of breast cancer cells (n=59) revealed that cells exhibiting high expression of FBP1 had a lower activity of Wnt/ß-Catenin pathway. FBP1 down-regulation enhanced the activity of Wnt/ß-Catenin pathway and increased the level of its downstream targets, including c-Myc and MMP7. Collectively, our findings indicate that elevated FBP1 is a critical modulator in breast cancer progression by altering glucose metabolism and the activity of Wnt/ß-Catenin pathway.

Brachyury promotes tamoxifen resistance in breast cancer by targeting SIRT1.

Tamoxifen is effective for treating estrogen receptor-alpha (ERα)-positive breast cancers. However, few molecular mediators of tamoxifen resistance have been elucidated. In the present study, we determine the underlying roles of Brachyury in tamoxifen resistance. Loss- and gain-of-function assay are utilized to confirm the oncogenic roles of Brachyury in breast cancer. Compared with the normal MCF10A cells, Brachyury is commonly overexpressed in breast cancer cell lines. Knockdown of Brachyury inhibits tamoxifen resistance, whereas overexpression of Brachyury enhances tamoxifen resistance as demonstrated increased cell viability and reduced cell apoptosis. Mechanistically, we demonstrate for the first time that Brachyury mediates tamoxifen resistance by regulating Sirtuin-1 (SIRT1). Collectively, our data, as a proof of principle, indicate that Brachyury is a candidate marker for predicting the clinical efficacy of tamoxifen and targeting SIRT1 could overcome resistance to tamoxifen in breast cancer cells.

Optimization of conditions for transfection with the Sofast gene vector.

We previously reported the synthesis and characterization of a novel cationic polymer gene vector. The present article further explored and optimized the working conditions of the Sofast gene vector both in vitro and in vivo, and improved its performance. The transfection conditions of Sofast, such as cell type, cell density, transfection time, N/P values and analysis time after transfection, were further explored. Moreover, the effects of the fusion peptide diINF-7 on transfection efficiency were examined. Sofast was successfully applied for the transfection of exogenous genes into more than 40 types of cell lines derived from humans, mice, monkeys and other species. When the cells were 50-80% confluent, Sofast possessed a better transfection efficiency. In most cases, Sofast also had a higher transfection efficiency when it was used to transfect cells that were seeded for several hours and had adhered to the substrate. The results from in vitro experiments indicate that the recommended Sofast to DNA mass ratio is 16:1, and the optimum analysis time after transfection is 48 h. The salt concentration in the Sofast working solution markedly affected the transfection efficiency. When conducting in vivo transfection, the working solution should be salt-free, whereas for in vitro transfection, it is more appropriate for the working solution to include certain salt concentrations. Finally, the results confirm that diINF-7 significantly promotes the transfection efficiency of Sofast. In conclusion, the present research not only established the optimal conditions for Sofast in the transfection of commonly used cells, but also built the foundations for in vivo and in vitro applications of Sofast, as well as its use in clinical practice.

Further evaluation of a novel nano-scale gene vector for in vivo transfection of siRNA.

In this research, a lipid-cationic polymer (LCP) containing the side-chain branching of brassidic acid was synthesized using chemical methods. As a gene vector for small interfering ribonucleic acid (siRNA) transfection, the efficiency and biosafety of LCP were preliminarily evaluated to investigate its possible application on tumor gene therapy. The toxicity, side-effects, and biosafety of LCP were investigated in animals based on the results of in vitro experiments. The siRNA against cyclooxygenase-2 (COX-2) was transfected by LCP to interfere with the COX-2 expression in nude-transplanted tumors. Hematoxylin and eosin stains, immunohistochemistry, reverse transcription-polymerase chain reaction, and Western blot were performed to evaluate the efficiency of LCP for siRNA transfection. The animal toxicity experiment showed that a high concentration of LCP had a low toxic effect on animals and did not induce allergic or pyrogenic reactions. The results from the in vivo transfection indicated that LCP could efficiently transfect siRNA and silence the target gene expression. The LCP gene vector for siRNA transfection is highly efficient during in vivo transfection and had low toxicity. From all aspects of tumor gene therapy and basic research, LCP is valuable for scientific research and medical applications.