As a special form of noncoding RNAs, circular RNAs (circRNAs) played important roles in regulating cancer progression mainly by functioning as miRNA sponge. While the function of circular RNA-ITCH (cir-ITCH) in lung cancer is still less reported, in this study, we firstly detected the expression of cir-ITCH in tumor tissues and paired adjacent noncancer tissues of 78 patients with lung cancer using a TaqMan-based quantitative real-time PCR (qRT-PCR). The results showed that the expression of cir-ITCH was significantly decreased in lung cancer tissues. In cellular studies, cir-ITCH was also enhanced in different lung cancer cell lines, A549 and NIC-H460. Ectopic expression of cir-ITCH markedly elevated its parental cancer-suppressive gene, ITCH, expression and inhibited proliferation of lung cancer cells. Molecular analysis further revealed that cir-ITCH acted as sponge of oncogenic miR-7 and miR-214 to enhance ITCH expression and thus suppressed the activation of Wnt/β-catenin signaling. Altogether, our results suggested that cir-ITCH may play an inhibitory role in lung cancer progression by enhancing its parental gene, ITCH, expression.

Optogenetics has been enthusiastically pursued in recent neuroscience research, and the causal relationship between neural activity and behavior is becoming ever more accessible. Here, we established knockin-mediated enhanced gene expression by improved tetracycline-controlled gene induction (KENGE-tet) and succeeded in generating transgenic mice expressing a highly light-sensitive channelrhodopsin-2 mutant at levels sufficient to drive the activities of multiple cell types. This method requires two lines of mice: one that controls the pattern of expression and another that determines the protein to be produced. The generation of new lines of either type readily expands the repertoire to choose from. In addition to neurons, we were able to manipulate the activity of nonexcitable glial cells in vivo. This shows that our system is applicable not only to neuroscience but also to any biomedical study that requires understanding of how the activity of a selected population of cells propagates through the intricate organic systems.

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Colon cancer is one of the most common malignancies worldwide and has a high mortality rate. Carvacrol is a major component of oregano and thyme essential oils and shows antitumor properties. Here, we investigated the effects of carvacrol on the proliferation and apoptosis of two human colon cancer cell lines, HCT116 and LoVo, and studied the molecular mechanisms of its antitumor properties. We found that carvacrol inhibited the proliferation and migration of the two colon cancer cell lines in a concentration-dependent manner. Cell invasion was suppressed after carvacrol treatment by decreasing the expression of matrix metalloprotease-2 (MMP-2) and MMP-9. Carvacrol treatment also caused cell cycle arrest in the G2/M phase and decreased cyclin B1 expression. Finally, carvacrol induced cell apoptosis in a dose-dependent manner. At the molecular level, carvacrol downregulated the expression of Bcl-2 and induced the phosphorylation of the extracellular-regulated protein kinase and protein kinase B (p-Akt). In parallel, carvacrol upregulated the expression of Bax and c-Jun N-terminal kinase. These results indicate that carvacrol might induce apoptosis in colon cancer cells through the mitochondrial apoptotic pathway and the MAPK and PI3K/Akt signaling pathways. Together, our results suggest that carvacrol may have therapeutic potential for the prevention and treatment of colon cancer.

BackgroundMicroglia-derived lysosomal cathepsins are important inflammatory mediators to trigger signaling pathways in inflammation-related cascades. Our previous study showed that the expression of cathepsin C (CatC) in the brain is induced predominantly in activated microglia in neuroinflammation. Moreover, CatC can induce chemokine production in brain inflammatory processes. In vitro studies further confirmed that CatC is secreted extracellularly from LPS-treated microglia. However, the mechanisms of CatC affecting neuroinflammatory responses are not known yet.MethodsCatC over-expression (CatCOE) and knock-down (CatCKD) mice were treated with intraperitoneal and intracerebroventricular LPS injection. Morris water maze (MWM) test was used to assess the ability of learning and memory. Cytokine expression in vivo was detected by in situ hybridization, quantitative PCR, and ELISA. In vitro, microglia M1 polarization was determined by quantitative PCR. Intracellular Ca2+ concentration was determined by flow cytometry, and the expression of NR2B, PKC, p38, IkBα, and p65 was determined by western blotting.ResultsThe LPS-treated CatCOE mice exhibited significantly increased escape latency compared with similarly treated wild-type or CatCKD mice. The highest levels of TNF-α, IL-1β, and other M1 markers (IL-6, CD86, CD16, and CD32) were found in the brain or serum of LPS-treated CatCOE mice, and the lowest levels were detected in CatCKD mice. Similar results were found in LPS-treated microglia derived from CatC differentially expressing mice or in CatC-treated microglia from wild-type mice. Furthermore, the expression of NR2B mRNA, phosphorylation of NR2B, Ca2+ concentration, phosphorylation of PKC, p38, IκBα, and p65 were all increased in CatC-treated microglia, while addition of E-64 and MK-801 reversed the phosphorylation of above molecules.ConclusionThe data suggest that CatC promotes microglia M1 polarization and aggravates neuroinflammation via activation of Ca2+-dependent PKC/p38MAPK/NF-κB pathway. CatC may be one of key molecular targets for alleviating and controlling neuroinflammation in neurological diseases.

As a newly identified oncogenic long noncoding RNA (lncRNA), prostate cancer-associated transcript 6 (PCAT6) promoted cellular proliferation and colony formation of prostate cancer. However, the biological function of PCAT6 in lung cancer is still largely unknown. In this study, we found that PCAT6 is significantly increased in cancer tissues compared to normal tissues and positively correlates with metastasis of lung cancer in patients. We then examined PCAT6 expression in lung cancer cell lines and identified that PCAT6 expression was significantly elevated in lung cancer cells compared to normal human bronchial epithelial (NHBE) cells, especially in CL1-5 and H446 cells. PCAT6 knockdown significantly inhibited cellular proliferation and metastasis, as well as induced early apoptosis of lung cancer cells. Molecular analysis revealed that PCAT6 regulated the expression of two pivotal cancer-related proteins, c-Myc and p53, in lung cancer cells. However, PCAT6 was not directly combined with c-Myc and p53 as confirmed by RNA immunoprecipitation. Finally, a retrospective study further revealed that PCAT6 negatively correlates with overall survival of lung cancer patients. In conclusion, these results suggest that PCAT6 could play an oncogenic role in lung cancer progression and may serve as a biomarker for prognosis of lung cancer patients.

Non-small cell lung cancer (NSCLC), which accounts for ~80 % of lung cancer cases, is one of the most common causes for cancer-related death. microRNAs (miRNAs) have been found to play critical roles in the development and progression of NSCLC. miR-27b has recently been reported as a tumor suppressor in several cancers, but its role in NSCLC remains poorly understood. In this study, we found that miR-27b was remarkably decreased in both NSCLC tissues and cell lines. Moreover, overexpression of miR-27b significantly suppressed NSCLC cells proliferation and invasion. LIM kinase 1 (LIMK1), an essential protein for malignant transformation, was found to be a target of miR-27b. Ectopic expression of LIMK1 dramatically dampened mir-27b action of cancer inhibition. Finally, LIMK1 was found to be negatively correlated with miR-27b in NSCLC patients. Our results demonstrated a tumor-suppressive role of miR-27b in NSCLC, suggesting a potential therapeutic target for NSCLC.

BackgroundCathepsin C (Cat C) functions as a central coordinator for activation of many serine proteases in inflammatory cells. It has been recognized that Cat C is responsible for neutrophil recruitment and production of chemokines and cytokines in many inflammatory diseases. However, Cat C expression and its functional role in the brain under normal conditions or in neuroinflammatory processes remain unclear. Our previous study showed that Cat C promoted the progress of brain demyelination in cuprizone-treated mice. The present study further investigated the Cat C expression and activity in lipopolysaccharide (LPS)-induced neuroinflammation in vivo and in vitro.MethodsC57BL/6 J mice were intraperitoneally injected with either 0.9% saline or lipopolysaccharide (LPS, 5 mg/kg). Immunohistochemistry (IHC) and in situ hybridization (ISH) were used to analyze microglial activation, TNF-α, IL-1β, IL-6, iNOS mRNAs expressions and cellular localization of Cat C in the brain. Nitrite assay was used to examine microglial activation in vitro; RT-PCR and ELISA were used to determine the expression and release of Cat C. Cat C activity was analyzed by cellular Cat C assay kit. Data were evaluated for statistical significance with paired t test.ResultsCat C was predominantly expressed in hippocampal CA2 neurons in C57BL/6 J mice under normal conditions. Six hours after LPS injection, Cat C expression was detected in cerebral cortical neurons; whereas, twenty-four hours later, Cat C expression was captured in activated microglial cells throughout the entire brain. The duration of induced Cat C expression in neurons and in microglial cells was ten days and three days, respectively. In vitro, LPS, IL-1β and IL-6 treatments increased microglial Cat C expression in a dose-dependent manner and upregulated Cat C secretion and its activity.ConclusionsTaken together, these data indicate that LPS and proinflammatory cytokines IL-1β, IL-6 induce the expression, release and upregulate enzymatic activity of Cat C in microglial cells. Further investigation is required to determine the functional role of Cat C in the progression of neuroinflammation, which may have implications for therapeutics for the prevention of neuroinflammation-involved neurological disorders in the future.