Heat-shock protein (hsp) expression can be induced by high temperature, exposure to cytokines or oxygen radicals, ischemia, hemodynamic overload, or viral infections. To determine whether surface expression of hsp60 occurs in aortic endothelial cells stressed by high temperature or cytokines, cells from rat aortas were cultivated and stained with several types of monoclonal antibodies against hsp60. Other antibodies, eg, those against intercellular adhesion molecule-1 (ICAM-1), or immune response-associated antigens were also used as controls. Positive staining of endothelial cells on the surface and in the cytoplasm was observed after pretreatment of the cells with cytokine-containing medium, tumor necrosis factor-alpha (TNF-alpha), or interleukin-1 alpha and labeling with a specific monoclonal antibody against hsp60 (II-13). Fluorescence-activated cell sorter analyses showed that over 80% of living endothelial cells stressed by cytokine-containing medium, by TNF-alpha, or at 42 degrees C, but not by interleukin-1 alpha, were positively surface stained with this antibody. Increased intensity of immunostaining with antibodies to ICAM-1 and immune response-associated antigen was also seen on the cytokine-stressed endothelial cells. Furthermore, when TNF-alpha stimulated endothelial cells labeled with 51Cr were incubated with antibody II-13 in the presence of complement, significant lysis occurred. In summary, endothelial cells stressed by high temperature or certain cytokines, eg, TNF-alpha, express hsp60 in the cytoplasm and on their surfaces, and these cells were susceptible to complement-dependent lysis by hsp60-specific antibody. These observations may be significant for elucidating the mechanisms of the involvement of immune reactions to hsp65/60 in initiating atherosclerosis.

The nematicidal activity of Chaetomium globosum NK102, culture filtrates, and chaetoglobosin A (ChA) purified by HPLC was evaluated on Meloidogyne incognita . The results showed that C. globosum NK102 significantly repelled second-stage juveniles (J2s). Both filtrates and ChA demonstrated strong adverse effects on J2 mortality with 99.8% at 300 μg ChA/mL (LC(50) = 77.0 μg/mL) at 72 h. ChA and filtrates did not affect egg hatch until 72 h of exposure. All filtrate treatments inhibited the J2 penetration even in 12.5% dilution treatment. Similarly, ChA (300 and 30 μg/mL) showed a significant inhibitory effect on J2 penetration. The number of eggs per plant was significantly reduced in the treatment of 30 mg ChA/kg soil by 63% relative to control plants, indicating the apparent negative effect on reproduction of M. incognita. The study demonstrated the nematicidal activity of ChA and suggested that it could be a potential biocontrol agent for integrated management of M. incognita.

Cisplatin (CDDP) is one of the most commonly used chemotherapy drugs for the treatment of various cancers. Although platinum-based therapies are highly efficacious against rapidly proliferating malignant tumors, the development of CDDP resistance results in significant relapse as well as decreased overall survival rates, which is a significant obstacle in CDDP-based cancer therapy. Long non-coding RNAs (lncRNAs) are involved in cancer development and progression by the regulation of processes related to chromatin remodeling, transcription, and posttranscriptional processing. Emerging evidence has recently highlighted the roles of lncRNAs in the development of CDDP resistance. In this review, we discuss the roles and mechanisms of lncRNAs in CDDP chemoresistance, including changes in cellular uptake or efflux of a drug, intracellular detoxification, DNA repair, apoptosis, autophagy, cell stemness, and the related signaling pathways, aiming to provide potential lncRNA-targeted strategies for overcoming drug resistance in cancer therapy.

BackgroundMicroRNAs (miRNAs) play important roles in cancer initiation and development. Epithelial–mesenchymal transition (EMT) is a form of cellular plasticity that is critical for embryonic development and metastasis. The purpose of the study was to determine the function and mechanism of miR-484 in initiation and development of cervical cancer (CC).MethodsWe determined the expression levels of miR-484 in cervical cancer tissues and cell lines with RT-qPCR. Prediction algorithms and EGFP reporter assay were performed to evaluate the targets for miR-484. MTT assay, colony formation assay, flow cytometric analysis, transwell cell migration and invasion assays, and detection of EMT markers were employed to investigate the roles of miR-484 and the targets in regulation of cell proliferation and EMT process. We also used rescue experiments to confirm the effect of miR-484 on CC cells through directly regulating the expression of its targets.ResultsFirstly we found miR-484 was down-regulated in cervical cancer tissues and cell lines compared with their matched non-cancerous tissues or normal cervical keratinocytes cells. Further studies revealed that overexpression of miR-484 suppressed the cell proliferation, while exacerbates apoptosis. Besides, miR-484 suppressed cellular migration, invasion and EMT process of CC cells. EGFP reporter assay showed that miR-484 binds to ZEB1 and SMAD2 3′UTR region and reduced their expression. The expression of miR-484 had reverse correlation with SMAD2/ZEB1, and SMAD2/ZEB1 had positive correlation with each other in cervical cancer tissues and cell lines. Furthermore, the ectopic expression of ZEB1 or SMAD2 could rescue the malignancies suppressed by miR-484, suggesting that miR-484 down-regulates ZEB1 and SMAD2 to repress tumorigenic activities.ConclusionWe found miR-484 inhibits cell proliferation and the EMT process by targeting both ZEB1 and SMAD2 genes and functions as a tumor suppressor, which may served as potential biomarkers for cervical cancer.

Chaetomium globosum is one of the most common fungi in nature. It is best known for producing chaetoglobosins; however, the molecular basis of chaetoglobosin biosynthesis is poorly understood in this fungus. In this study, we utilized RNA interference (RNAi) to characterize a polyketide synthase gene, pks-1, in C. globosum that is involved in the production of chaetoglobosin A. When pks-1 was knocked down by RNAi, the production of chaetoglobosin A dramatically decreased. Knock-down mutants also displayed a pigment-deficient phenotype. These results suggest that the two polyketides, melanin and chaetoglobosin, are likely to share common biosynthetic steps. Most importantly, we found that pks-1 also plays a critical role in sporulation. The silenced mutants of pks-1 lost the ability to produce spores. We propose that polyketides may modulate cellular development via an unidentified action. We also suggest that C. globosum pks-1 is unique because of its triple role in melanin formation, chaetoglobosin biosynthesis and sporulation. This work may shed light on chaetoglobosin biosynthesis and indicates a relationship between secondary metabolism and fungal morphogenesis.

Neuronal apoptosis after intracerebral hemorrhage (ICH) plays an essential role in neurological deterioration. Preclinical studies have shown that EGb761, an extract of Ginkgo biloba, is neuroprotective in some other neurological diseases with apoptosis. This study was conducted to investigate the potential neuroprotective effect of EGb761 on neuronal apoptosis in experimental ICH. A model of ICH was induced in C57BL/6 mice by injecting collagenase. EGb761 was administered for 21 days and neurologic behaviors were assessed at 1, 3, 7, 14, and 21 days after ICH. RNAi-mediated knockdown of p90 ribosomal S6 kinase 1 (RSK1) was used to further investigate the role of RSK1 in EGb761-induced neuroprotective effects. Neuronal death was determined by TUNEL staining. The image datasets of neurovascular networks were acquired via micro-optical sectioning tomography (MOST). The glycogen synthase kinase-3β (GSK3β) activity was assayed using commercial kit. Primary cultured cortical neurons were exposed to ferrous iron and treated with EGb761. Apoptotic neurons were counted by flow cytometry. RSK1, GSK3β, phosphorylated-GSK3β (pGSK3β), Bcl2, Bax, cleaved-caspase3 (CC3), and VEGF were measured by Western blot. The pGSK3β was also detected by immunofluorescence staining. We found that mice in EGb761 group performed better on rotarod test. Reduced TUNEL-positive neurons and richer microvascular networks were observed in mice treated with EGb761. EGb761 attenuates neuronal apoptosis induced by ferrous iron counted by flow cytometry in vitro. Decreased GSK3β activity was observed in EGb761-treated mice compared with mice with ICH. EGb761 increased the expression of pGSK3β (Ser9), RSK1 and the Bcl2/Bax ratio, and VEGF and decreased CC3 expression. In conclusion, EGb761 reduces neuronal apoptosis and promotes angiogenesis in experimental intracerebral hemorrhage via RSK1/GSK3β pathway.

BackgroundEmerging evidence indicates that dysregulation of microRNAs (miRNAs) contributes to cervical cancer (CC) tumorigenesis and development. Previous work showed that miR-484 which regulated the EMT process was obviously downregulated in CC. However, little is known about the precise mechanism.ResultsWe found that the deficiency of EZH2-recruited DNA methyltransferases DNMT1 reduced the CpG methylation of miR-484 promoter and then increased the miR-484 expression. Furthermore, the cell membrane-bound matrix metalloproteinase (MMP14) and the hepatocyte nuclear factor 1A (HNF1A) were found to be downregulated by miR-484. miR-484 repressed the expression of MMP14 and HNF1A inhibiting CC growth and metastasis in vitro and in vivo. Upregulation of MMP14 and HNF1A promotes the CC cell adhesion and EMT, all of which contribute to cell motility and metastasis. Moreover, miR-484 negatively regulates the WNT/MAPK and TNF signaling pathway by downregulating HNF1A and MMP14 respectively. Thus, miR-484, who is downregulated by DNMT1-mediated hypermethylation in its promoter, functions as a tumor suppressor by inhibiting MMP14 and HNF1A expression in CC.ConclusionOur finding characterizes miR-484 as a key suppressive regulator in CC metastasis and reveals a DNMT1-mediated epigenetic mechanism for miR-484 silencing, expanding our understanding of the molecular mechanism underlying CC progression and metastasis.Graphical abstract

MicroRNA (miRNA) dysregulation has been associated with carcinogenesis in many cancers, including human colorectal cancer (hCRC). However, the effect and mechanism of miR-377-3p on CRC remains elusive. Herein, we first found that miR-377-3p was upregulated in CRC tissues and promoted tumorigenic activity by accelerating the G -S phase transition, promoting cell proliferation and epithelial-mesenchymal transition (EMT) while repressing apoptosis in CRC cells. Glycogen synthase kinase-3β (GSK-3β) was a direct target of miR-377-3p, and upregulated by miR-377-3p. Knockdown of GSK-3β partly rescued miR-377-3p-mediated malignancy characteristics. Most importantly, we showed that miR-377-3p promoted carcinogenesis by activating NF-κB pathway. Taken together, our results first reported that miR-377-3p functions as an oncogene and promotes carcinogenesis via upregulating GSK-3β expression and activating NF-κB pathway in hCRC cells.