Up-regulation of miR-190b promoted growth, invasion, migration and inhibited apoptosis of Wilms' tumor cells by repressing the PTEN expression.

OBJECTIVE: Wilms' tumor (WT) is the most common malignant tumor in the children's urogenital system. MiR-190b was found to participate in the development and progression of several cancers. However, the molecular mechanism of miR-190b in WT is still unclear. PATIENTS AND METHODS: We detected the miR-190b in WT tissue samples compared to adjacent normal samples as well as in WT patients' blood sample compared to normal volunteers using qRT-PCR. With over-expression and knockdown of miR-190b in WT-derived cell line SK-NEP-1, we next studied cell proliferation, cell circle, apoptosis, invasion and migration abilities change caused by miR-190b ectopic expression. Dual-luciferase assay and Western-blot analysis were used to explain the mechanism of miR-190b in WT. RESULTS: MiR-190b was over-expressed in WT tissue and blood samples compared to normal group, relatively. Up-regulation of miR-190b in SK-NEP-1 cells significantly increased the growth and decreased the apoptosis of cells, while its down-regulation reduced cell proliferation and promoted cell apoptosis of SK-NEP-1. Also, cell invasion and migration abilities were significantly improved after miR-190b over-expression. Moreover, PTEN was proved to be a direct target of miR-190b and its protein level was remarkably decreased after miR-190b up-regulation. CONCLUSIONS: miR-190b over-expressed in WT and promoted cell proliferation, invasion and migration while reduced cell apoptosis of WT cells by repressing PTEN repression, which might provide a potential target for WT diagnosis and therapy.

Autophagy protects chondrocytes from glucocorticoids-induced apoptosis via ROS/Akt/FOXO3 signaling.

OBJECTIVE: Glucocorticoids (GCs) have been widely used in the management of osteoarthritis (OA) and rheumatoid arthritis (RA). Nevertheless, there has been some concern about their ability of increasing reactive oxygen species (ROS) in the cartilage. Forkhead-box class O (FOXO) transcription factors have been proved to have a protective role in chondrocytes through regulation of autophagy and defending oxidative stress. The objective of this study was to investigate the role of FOXO3 in Dex-induce up-regulation of ROS. DESIGN: Healthy cartilages debris from six patients were used for chondrocytes culture. After the treatment of dexamethasone (Dex), the ROS levels, autophagic flux, the expression of FOXO3 in chondrocytes were measured. RNA interference technique was also used to determine the role of FOXO3 in Dex-induced autophagy. The metabolism of the extra-cellular matrix was also investigated. THE RESULTS: Dex increased intracellular ROS level, the expression of Akt, FOXO3 as well as autophagy flux in human chondrocytes. The expression of aggrecanases also increased after the treatment of Dex. Catalase, the ROS scavenger, suppressed Dex-induced up-regulation of autophagy flux and expression of aggrecanases and Akt. MK-2206 and LY294002, the PI3K/Akt inhibitors, repressed Dex-induced up-regulation of FOXO3. Silencing FOXO3 resulted in down-regulation of Dex-induced autophagy. Moreover, knockdown of FOXO3 increased Dex-induced apoptosis as well as ROS levels in chondrocytes. In addition, up-regulation of autophagy by Rapamycin resulted in decreasing ROS level in chondrocytes. CONCLUSION: Dex could advance the degenerative process in cartilage. Autophagy was induced in response to Dex-induced up-regulation of ROS via ROS/Akt/FOXO3 signal pathway.

IFN-γ induces aberrant CD49b⁺ NK cell recruitment through regulating CX3CL1: a novel mechanism by which IFN-γ provokes pregnancy failure.

Interferon-γ (IFN-γ), a pleiotropic lymphokine, has important regulatory effects on many cell types. Although IFN-γ is essential for the initiation of uterine vascular modifications and maintenance of decidual integrity, IFN-γ administration can also cause pregnancy failure in many species. However, little is known about the effector mechanisms involved. In this study, using an IFN-γ-induced abortion mouse model, we reported that no Dolichos biflorus agglutinin lectin-positive uterine natural killer (uNK) cells were observed in the uteri from IFN-γ-induced abortion mice. By contrast, the percentage of CD3(-)CD49b(+) NK cells in the uterus and blood from a foetal resorption group was significantly higher than that of the control group. Similarly, significantly upregulated expression of CD49b (a pan-NK cell marker), CX3CL1 and CX3CR1 (CX3CL1 receptor) was detected in the uteri of IFN-γ-induced abortion mice. Using isolated uterine stromal cells, we showed that upregulated expression of CX3CL1 by IFN-γ was dependent on a Janus family kinase 2-signal transducers and activators of transcription 1 (JAK2-STAT1) pathway. We further demonstrated the chemotactic activity of CX3CL1 in uterine stromal cell conditioned medium on primary splenic NK cells. Finally, we observed increased recruitment of CD49b(+) NK cells into the endometrium after exogenous CX3CL1 administration. Collectively, our findings indicate that IFN-γ can significantly increase uterine CX3CL1 expression via activation of the JAK2-STAT1 pathway, thus inducing CD49b(+) NK cell uterine homing, and eventually provoke foetal loss. Thus, we provide a new line of evidence correlating the deleterious effects of IFN-γ on pregnancy with the aberrant regulation of CX3CL1 and CD49b(+) NK cells.

The prognosis of hearing impairment complicating HIV-negative cryptococcal meningitis.

Eight patients who had sensorineural hearing loss (SNHL) associated with cryptococcal meningitis were studied. After a minimum 3-year follow-up, one had died. Among the seven survivors, three had improved, two stabilized, and two progressed. Predictive factors included visual disturbance, meningeal enhancements on MRI, and a CSF cryptococcal antigen titer of >1:1,024. SNHL accounted for 30.8% (8/26) of cryptococcal meningitis patients in our study.