MicroRNA-15a inhibits inflammatory response and apoptosis after spinal cord injury via targeting STAT3.

OBJECTIVE: To clarify the function of microRNA-15a in the spinal cord injury (SCI) and its potential mechanism. PATIENTS AND METHODS: The plasma levels of microRNA-15a and signal transducer and activator of transcription 3 (STAT3) in SCI patients were determined by quantitative Real Time-Polymerase Chain Reaction (qRT-PCR). The correlation between the expressions of microRNA-15a and STAT3 was analyzed. The in vitro SCI model was established in H2O2-induced C8-D1A and C8B4 cells, and in vivo SCI model was established in mice by hitting T10. The mRNA and protein expressions of tumor necrosis factor-α (TNF-α) and interleukin 6 (IL-6) were detected in the SCI model. The apoptosis was examined by flow cytometry or TUNEL staining, respectively. The motor function of mouse hindlimb was evaluated using the Basso Beattie Bresnahan (BBB) standard scale. The target gene of microRNA-15a was predicted by bioinformatics and further verified by dual-luciferase reporter gene assay. The expression changes of target genes in C8-D1A and C8B4 cells with microRNA-15a overexpression or knockdown were examined by qRT-PCR and Western blot. Finally, rescue experiments were performed to evaluate the regulatory effects of microRNA-15a and STAT3 on cell apoptosis. RESULTS: MicroRNA-15a was lowly expressed in plasma of SCI patients, while STAT3 was highly expressed with a negative correlation to microRNA-15a. Identically, microRNA-15a was lowly expressed in H2O2-induced C8-D1A and C8B4 cells, and STAT3 was highly expressed. MicroRNA-15a overexpression downregulated mRNA and protein levels of TNF-α and IL-6 in C8-D1A and C8B4 cells. BBB score was markedly low in SCI mice relative to controls. SCI mice injected with microRNA-15a mimics had higher BBB score than those injected with negative control. Besides, SCI mice with microRNA-15a overexpression had downregulated expressions of STAT3, TNF-α, and IL-6 in the impaired spinal cord tissues, as well as lower apoptotic rate. Through bioinformatics, we found binding sites between STAT3 and microRNA-15a. Their binding conditions were further verified by dual-luciferase reporter gene assay. Moreover, STAT3 expression was negatively regulated by microRNA-15a. Finally, rescue experiments showed that STAT3 overexpression could reverse the regulatory effects of microRNA-15a on expressions of TNF-α and IL-6, as well as apoptosis. CONCLUSIONS: MicroRNA-15a expression decreases in the SCI model, which participates in the process of SCI by regulating inflammatory response and cell apoptosis via targeting STAT3.

LINC00511 promotes the progression of non-small cell lung cancer through downregulating LATS2 and KLF2 by binding to EZH2 and LSD1.

OBJECTIVE: Lung cancer is a malignant tumor with extremely high morbidity and mortality. Recent studies have identified the vital role of LINC00511 (lncRNAs) in the development and progression of non-small cell lung cancer (NSCLC). In this research, we aim to explore the biological function of LINC00511 in the development and metastasis of NSCLC. PATIENTS AND METHODS: LINC00511 expression in 57 paired NSCLC patients' tissues and matched normal tissues were detected by Real-time quantitative polymerase chain reaction (RT-qPCR). Cell proliferation assay, colony formation assay and transwell assay were conducted to observe the biological behavior changes of NSCLC cells through the influence of LINC00511. In addition, dual-luciferase reporter gene assay, RNA immunoprecipitation assay (RIP) and, chromatin immunoprecipitation (ChIP) were performed to discover the potential targets of LINC00511 in NSCLC cells. RESULTS: LINC00511 was highly expressed in NSCLC tissues and cell lines compared with controls. LINC00511 expression was positively correlated with tumor size, tumor stage, lymph node metastasis and distant metastasis, but negatively correlated with overall survival (OS) of NSCLC patients. Receiver Operating Characteristic (ROC) curves suggested that LINC00511 could be an effective indicator to distinguish NSCLC patients from normal people. Cell counting kit-8 (CCK-8), flow cytometry and transwell assay showed that knockdown of LINC00511 in A549 cells decreased viability, accelerated apoptosis and inhibited invasive and migratory abilities. Overexpression of LINC00511 in PC9 cells obtained the opposite biological effects. Chromatin fractionation predicted that LINC00511 was mainly distributed in the nucleus. RIP and ChIP assay showed that LINC00551 directly bound to lysine-specific demethylase 1 (LSD1) and enhancer of zeste homolog 2 (EZH2). It inhibited expressions of LATS2 and KLF2 by binding to their promoter regions. CONCLUSIONS: LINC00511 is upregulated in NSCLC tissues and cell lines. It is closely related to tumor size, tumor stage, lymph node metastasis and, distant metastasis of NSCLC patients. Knockdown of LINC00511 attenuates proliferative, migratory and invasive capacities, but induces apoptosis of NSCLC cells. LATS2 and KLF2 are target genes of LINC00511, which are regulated by LINC00511 through binding to EZH2 and LSD1, thus influencing the progression of NSCLC.

MicroRNA-615-3p promotes the osteoarthritis progression by inhibiting chondrogenic differentiation of bone marrow mesenchymal stem cells.

OBJECTIVE: To investigate whether microRNA-615-3p participates in the development and progression of osteoarthritis by regulating chondrogenic differentiation of bone marrow mesenchymal stem cells. MATERIALS AND METHODS: Bone marrow mesenchymal stem cells (BMSCs) were isolated from rat bone marrow and identified by flow cytometry. After chondrogenic differentiation was induced in BMSCs, expression levels of chondrogenic-specific genes were then detected by quantitate Real-time polymerase chain reaction (qRT-PCR). Expression levels of inflammatory cytokines were detected by enzyme-linked immunosorbent assay (ELISA). Protein expression of SOX9 after overexpression or knockdown of microRNA-615-3p was detected by Western blot, respectively. RESULTS: MicroRNA-615-3p was down-regulated in the process of chondrogenic differentiation of BMSCs. The mRNA expressions of chondrogenic-specific markers, COL2A1, COL10A1, ACAN and MATN3 were decreased after microRNA-615-3p overexpression in BMSCs. Overexpressed microRNA-615-3p down-regulated protein expression of SOX9. Expression levels of inflammatory cytokines, including interleukin-1 (IL-1), interleukin-6 (IL-6), interleukin-α (IL-α) were increased after overexpression of microRNA-615-3p, while inhibition of microRNA-615-3p expression obtained the opposite result. In addition, overexpression of SOX9 rescued the effect induced by microRNA-615-3p on inflammatory cytokines. CONCLUSIONS: MicroRNA-615-3p participates in the development and progression of osteoarthritis by increasing the expressions of inflammatory cytokines and inhibiting chondrogenic differentiation of BMSCs.

Cisplatin induces apoptosis of hepatocellular carcinoma LM3 cells via down-regulation of XIAP.

OBJECTIVE: Cisplatin is an important anti-cancer drug. However, the molecular mechanism of cisplatin on inhibition of the proliferation of liver cancer cells is unclear. Thus, we aimed to investigate the regulatory role of cisplatin on the growth and apoptosis of hepatoma LM3 cells. MATERIALS AND METHODS: LM3 cells were treated with cisplatin (2 µmol/L) for 48 h. MTT assay, flow cytometry, and caspase-3 activity assay were used to detect the growth, proliferation and apoptosis of LM3 cells. Western blot was applied to detect the expression of the inhibitor of apoptosis protein, XIAP. siRNA was used to knockdown the level of XIAP followed by cisplatin (2 µmol/L) treatment, and then the apoptosis of LM3 cells was measured. RESULTS: The treatment of cisplatin significantly inhibited the growth but induced the apoptosis of LM3 cells. Cisplatin also downregulated the expression of XIAP. The downregulation of XIAP by using siRNA enhanced the apoptosis of LM3 cells induced by cisplatin. CONCLUSIONS: Downregulation of XIAP enhanced the proapoptotic effect of cisplatin on LM3 cells, suggesting that XIAP might be used as a potential target in the treatment of liver cancer.

FBXL5 attenuates RhoGDI2-induced cisplatin resistance in gastric cancer cells.

OBJECTIVE: The hemerythrin-like domain of F-box and leucine-rich repeat protein 5 (FBXL5), an E3 ubiquitin ligase subunit, has critical roles in the regulation of cancer cells metastasis and chemoresistance by targeting diverse substrates for ubiquitin-mediated destruction. MATERIALS AND METHODS: Here, we report that FBXL5 interacts with Rho GDP dissociation inhibitor 2 (RhoGDI2) and attenuates RhoGDI2-induced cisplatin resistance in gastric cancer cells. By utilizing immunoprecipitation (IP) coupled with mass spectrometry assay, we found that FBXL5 regulated gastric cancers migration via cortactin destruction. RESULTS: Depletion of FBXL5 enhances cisplatin resistance of gastric cancer cells through Erk and p38 activation. However, FBXL5 did not affect the abundance and stability of RhoGDI2. Instead, FBXL5 was rapidly degraded in response to cisplatin treatment in RhoGDI2-overexpressing gastric cancer cells. CONCLUSIONS: Collectively, our data suggested the existence of a FBXL5-RhoGDI2 negative feedback loop in RhoGDI2-induced cisplatin resistance in gastric cancer cells, implicating FBXL5 as a novel and promising therapeutic target for RhoGDI2-induced cisplatin resistance gastric cancers.

Genetic variants of the genes encoding zinc finger protein 313 and interleukin-13 confer a risk for psoriasis in a Chinese Uygur population.

BACKGROUND: Recent work using genome­wide association studies (GWAS) in Chinese Han and white populations have discovered several novel psoriasis susceptibility genes. AIM: To examine whether the risk loci for psoriasis identified in previous GWAS in a white population are also associated with psoriasis in a Chinese Uygur population in Xinjiang. METHODS: Genotyping analysis of eight single-nucleotide polymorphisms (SNPs) associated with psoriasis was performed for 539 patients with psoriasis and 749 controls, all of Chinese Uygur descent, using a commercial assay. RESULTS: Two SNPs had an association with psoriasis in this Chinese Uygur population: SNP rs495337 in the gene encoding for zinc finger protein 313 (P < 0.001; OR = 0.80) and SNP rs20541 of the gene encoding for interleukin-13 (P < 0.001; OR = 0.82). In subgroup analyses, the two SNPs were significantly associated (P < 0.05) with type I psoriasis, Rs495337 showed statistically difference between positive family history of psoriasis patients and controls whereas rs20541 might preferentially associated with negative family history psoriasis patients. Interestingly, using multifactor dimensionality reduction, a significant two-locus interaction was seen between rs495337 and rs20541, with a crossvalidation consistency of 4/5 and average balanced prediction (accuracy 55.5%, P < 0.001). CONCLUSIONS: ZNF313 and IL-13 are associated with risk for psoriasis in a Chinese Uygur population, and there is an effect of interaction between the two genes on this risk.

Self-Organized Ni Nanocrystal Embedded in BaTiO3 Epitaxial Film.

Ni nanocrystals (NCs) were embedded in BaTiO3 epitaxial films using the laser molecular beam epitaxy. The processes involving the self-organization of Ni NCs and the epitaxial growth of BaTiO3 were discussed. With the in situ monitoring of reflection high-energy electron diffraction, the nanocomposite films were engineered controllably by the fine alternation of the self-organization of Ni NCs and the epitaxial growth of BaTiO3. The transmission electron microscopy and the X-ray diffraction characterization confirmed that the composite film consists of the Ni NCs layers alternating with the (001)/(100)-oriented epitaxial BaTiO3 separation layers.