Arabidopsis AGAMOUS-LIKE16 and SUPPRESSOR OF CONSTANS1 regulate the genome-wide expression and flowering time.

Flowering transition is tightly coordinated by complex gene regulatory networks, in which AGAMOUS-LIKE 16 (AGL16) plays important roles. Here, we identified the molecular function and binding properties of AGL16 and demonstrated its partial dependency on the SUPPRESSOR OF CONSTANS 1 (SOC1) function in regulating flowering. AGL16 bound to promoters of more than 2,000 genes via CArG-box motifs with high similarity to that of SOC1 in Arabidopsis (Arabidopsis thaliana). Approximately 70 flowering genes involved in multiple pathways were potential targets of AGL16. AGL16 formed a protein complex with SOC1 and shared a common set of targets. Intriguingly, only a limited number of genes were differentially expressed in the agl16-1 loss-of-function mutant. However, in the soc1-2 knockout background, AGL16 repressed and activated the expression of 375 and 182 genes, respectively, with more than a quarter bound by AGL16. Corroborating these findings, AGL16 repressed the flowering time more strongly in soc1-2 than in the Col-0 background. These data identify a partial inter-dependency between AGL16 and SOC1 in regulating genome-wide gene expression and flowering time, while AGL16 provides a feedback regulation on SOC1 expression. Our study sheds light on the complex background dependency of AGL16 in flowering regulation, thus providing additional insights into the molecular coordination of development and environmental adaptation.

A case-control study on the association of intestinal flora with ulcerative colitis.

The association between intestinal flora and ulcerative colitis (UC) was studied in order to provide a basis and method for clinical treatment. Fresh fecal samples were collected from 30 active UC patients and 10 healthy controls. The intestinal flora DNA from each sample was extracted and 16S rRNA gene sequencing was carried out using HiSeq platform to identify the intestinal flora in fecal samples. The richness and diversity of intestinal flora in UC patients were significantly lower than those in healthy control group (P < 0.05). Significant differences were observed between the intestinal flora-species of UC patients and healthy controls. Synergistetes (P < 0.01) and Firmicutes (P < 0.05), along with probiotics Veillonella (P < 0.01), Ruminococcus and Coprococcus (P < 0.05) in the UC patients were lower than that in the healthy controls significantly. Furthermore, compared with the control group, Tenericutes (P < 0.01) and intestinal pathogenic bacteria, including Bacteroides (P < 0.01), Escherichia and Sutterella (P < 0.05) were significantly increased. The incidence of UC is significantly associated with the changes in intestinal flora. Changes in intestinal flora may lead to a decrease in the diversity of intestinal flora or to the enrichment of a particular intestinal flora.

Silencing of Long Non-Coding RNA HOTAIR Alleviates Epithelial-Mesenchymal Transition in Pancreatic Cancer via the Wnt/ß-Catenin Signaling Pathway.

PURPOSE: Pancreatic cancer (PC) is a malignancy with poor prognosis and controversial treatment options. Long non-coding RNA (lncRNA) is a significant factor in the development of PC. In the current study, the possible effects of HOTAIR on the epithelial-mesenchymal transition (EMT) of PC and the related mechanisms were investigated. METHODS: The PC models were induced by 10 mg/100 g dimethylbenzoanthracene (DMBA) in pancreas. Mice were injected with the HOTAIR mimic and HOTAIR shRNA to determine the role of HOTAIR in PC. Subsequently, the expression of HOTAIR in PC cells was assayed. To determine the mechanism of HOTAIR in PC, human PC cell line PANC-1, Miapaca-2 and human normal pancreatic ductal epithelial cell line HPDE6-C7 were transfected with the HOTAIR mimic, the shRNA against HOTAIR, the Wnt/b-catenin activator (LiCl), and the Wnt/b-catenin inhibitor (XAV939), respectively. Moreover, the expressions of the Wnt/ß-catenin signaling pathway-related genes (ß-catenin, cyclinD1, c-myc, LEF-1 and c-Jun) and the levels of the EMT markers (E-cadherin, N-cadherin and Vimentin) were determined. Finally, the cell biological processes were evaluated by functional experiments. RESULTS: HOTAIR was found to be highly expressed in the PC cells in mice. The expression of ß-catenin, cyclinD1, c-myc, LEF-1 and c-Jun, N-cadherin and Vimentin was found to be decreased, while the expression of E-cadherin was found to be increased subsequent to the silencing of HOTAIR in human PC cell lines PANC-1 and Miapaca-2. Additionally, it was observed that the silencing of HOTAIR could inhibit the Wnt/ß-catenin signaling pathway to alleviate EMT of tumor cells and inhibit the capacities of cell proliferation, migration, and invasion. CONCLUSION: The key finding of the present study is that the silencing of HOTAIR could potentially inhibit EMT and growth of PC through the Wnt/ß-catenin signaling pathway, providing a novel therapy for PC.

A mis-regulated cyclic nucleotide-gated channel mediates cytosolic calcium elevation and activates immunity in Arabidopsis.

Calcium (Ca2+ ) is a second messenger for plant cell surface and intracellular receptors mediating pattern-triggered and effector-triggered immunity (respectively, PTI and ETI). Several CYCLIC NUCLEOTIDE-GATED CHANNELS (CNGCs) were shown to control transient cytosolic Ca2+ influx upon PTI activation. The contributions of specific CNGC members to PTI and ETI remain unclear. ENHANCED DISEASE SUSCEPTIBLITY1 (EDS1) regulates ETI signaling. In an Arabidopsis genetic screen for suppressors of eds1, we identify a recessive gain-of-function mutation in CNGC20, denoted cngc20-4, which partially restores disease resistance in eds1. cngc20-4 enhances PTI responses and ETI hypersensitive cell death. A cngc20-4 single mutant exhibits autoimmunity, which is dependent on genetically parallel EDS1 and salicylic acid (SA) pathways. CNGC20 self-associates, forms heteromeric complexes with CNGC19, and is phosphorylated and stabilized by BOTRYTIS INDUCED KINASE1 (BIK1). The cngc20-4 L371F exchange on a predicted transmembrane channel inward surface does not disrupt these interactions but leads to increased cytosolic Ca2+ accumulation, consistent with mis-regulation of CNGC20 Ca2+ -permeable channel activity. Our data show that ectopic Ca2+ influx caused by a mutant form of CNGC20 in cngc20-4 affects both PTI and ETI responses. We conclude that tight control of the CNGC20 Ca2+ ion channel is important for regulated immunity.

IL-6/STAT3/SOCS3 signaling pathway playing a regulatory role in ulcerative colitis carcinogenesis.

OBJECTIVE: Large-scale clinical studies have shown that ulcerative colities were related with colorectal cancer. In this study, animal model was established by AOM/DSS method to explore the activation of IL-6-STAT3-SOCS3 signaling pathway and the expression of pathway-related proteins in ulcerative colitis carcinogenesis, in order to lay a foundation for exploring the regulation mechanism of IL-6/STAT3/SOCS3 signaling pathway in ulcerative colitis carcinogenesis. METHOD: AOM/DSS modeling method was used to establish animal models of ulcerative colitis carcinogenesis; colonic mucosa specimens were collected at different time points for pathological examination. Immunohistochemical method and western blot were used to detect the expression of IL6, STAT3 and SOCS3 protein in the control group, UC model + empty vector group and UC model + STAT3 knockout group. RESULTS: In UC model + empty vector group, IL6 and STAT3 expression was increased as lesion degree increased (P < 0.05). The expression of SOCS3 was weakened and the degree of activation decreased (P < 0.05). IL6 expression increased in UC model + STAT3 knockout group (P < 0.05) while the expression of SOCS3 decreased; compared with the UC model + empty vector group, there was a significant difference (P < 0.05). CONCLUSION: The expression and activation of IL6 and STAT3 expression were enhanced in ulcerative colitis carcinogenesis, and their expression increased with the lesion degree increased, reflecting the disease progression to a certain extent. The expression and activation of SOCS3 expression decreased. STAT3 had a certain effect on the expression of SOCS3, playing a certain regulatory role in ulcerative colitis carcinogenesis.

Combinatorial Intervention with Mesenchymal Stem Cells and Granulocyte Colony-Stimulating Factor in a Rat Model of Ulcerative Colitis.

BACKGROUND: Bone marrow mesenchymal stem cells sometimes improve symptoms of inflammatory bowel disease. AIM: To test the effects of combined granulocyte colony-stimulating factor (G-CSF) and MSC therapy in a rat model of ulcerative colitis (UC). METHODS: Seventy-two rats with TNBS-induced UC were divided into control or treatment groups: control (no disease and no treatment), no treatment (model), 5-aminosalicylate (5-ASA) enema, or MSCs (labeled with BrdU) with (MSC/GCSF) or without (MSC) G-CSF, and G-CSF alone (GCSF). On days 14 and 28 post-treatment, macroscopic and histological appearances were assessed and the disease activity index (DAI) scored to evaluate the severity of disease. BrdU-labeled MSCs were identified by immunofluorescence to confirm transplantation and their location. The inflammatory profile of each group was evaluated by measuring expression of nuclear NF-κB p65, serum TNF-α, and IL-10 and by activity of mucosal myeloperoxidase (MPO). RESULTS: Rats receiving MSC and G-CSF combination therapy had increased recruitment of MSCs to the colonic mucosa compared with rats receiving MSC transplantation alone. On day 28, the DAI, MPO activity, serum TNF-α and IL-10 levels, and NF-κB p65 expression in the combination therapy group were significantly lower compared to animals receiving no treatment, MSCs alone, or G-CSF alone (P < 0.05). CONCLUSION: Intravenously transplanted MSCs migrate and distribute to the colon to effectively alleviate the symptoms of UC, while G-CSF enhances this effect via an anti-inflammatory effect and improvement in the pathologic features of UC. G-CSF may be a promising therapeutic regulator of MSCs that can improve therapeutic outcomes in patients with UC.

MDM2 SNP309T>G polymorphism increases susceptibility to hepatitis B virus-related hepatocellular carcinoma in a northeast Han Chinese population.

BACKGROUND AND AIMS: The murine double minute 2 (MDM2) gene encodes a negative regulator of the tumour protein p53. A single nucleotide polymorphism (SNP) in MDM2 promoter, SNP309 T > G, has been showed to influence MDM2 protein expression and accelerate tumour formation. To investigate further the role of this locus, we examined the association of the SNP with hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) in a northeast Han Chinese population. METHODS: MDM2 SNP309 was genotyped in 310 HBV-related HCC patients, 314 non-HCC subjects with HBV infection and 480 healthy controls by using a PCR-RFLP method. RESULTS: Significant differences of MDM2 SNP309 were detected between HBV-related HCC patients and healthy controls (OR 1.729, 95%CI 1.369-2.183, P < 0.0001) or non-HCC subjects with HBV infection (OR 1.351, 95% CI 1.060-1.722, P = 0.015) by a logistic regression analysis. Our data also revealed that subjects with the G allele had higher HBV-related HCC susceptibility than those with the T allele in various genetic models. In a meta-analysis, where we pooled our data with other published studies, the association between this loci and the disease was further confirmed (pooled OR 1.54, 95% CI 1.37-1.72, P < 0.0001). CONCLUSIONS: These results suggested that the MDM2 SNP309 might influence the risk of developing HBV-related HCC in a northeast Han Chinese population.

miR-199a regulates the tumor suppressor mitogen-activated protein kinase kinase kinase 11 in gastric cancer.

Small noncoding microRNAs (miRNAs) have been shown to play an important role in tumor proliferation and metastasis. However, their function and mechanism in the proliferation and metastasis of gastric cancer has not yet been elucidated. Here, we investigated the relationship between miRNA-199a and gastric cancer proliferation and metastasis. Using real-time reverse-transcriptase (RT)-polymerase chain reaction, we found that miR-199a is highly expressed in gastric cancer compared to normal gastric tissues and in metastatic, compared to non-metastatic gastric cancer tissues. MiR-199a positively regulated gastric cancer cell proliferation, migration and invasion. Further studies showed that mitogen-activated protein kinase kinase kinase 11 was significantly down-regulated by miR-199a at the post-transcriptional level and, the level of miR-199a expression in gastric cancer significantly correlated with clinical progression. These findings suggested miR-199a promoted proliferation and metastasis of gastric cancer cells through a regulatory pathway in gastric cancer that has yet to be described. miR-199a may be useful as a new potential therapeutic target for gastric cancer.

[Influence of artificial pneumoperitoneal media on colon carcinoma cell proliferation in vitro].

OBJECTIVE: To evaluate the influence of different pneumoperitoneal media on colon carcinoma LS-174T cell proliferation in vitro. METHODS: The artificial pneumoperitoneum was established. The proliferation of LS-174T cells was detected by MTT assay and soft agar clone formation assay. Expression of HIF-1alpha and VEGF was examined by immunohistochemistry. Apoptosis of LS-174T cells was analyzed by AO/EB double fluorescein stain and flow cytometry. RESULTS: The growth speed and proliferating capacity of LS-174T cells in CO(2) pneumoperitoneum group[A:0.37 +/- 0.02,formation (32.8 +/- 3.6)%] were significantly higher than those in control group [A:0.33 +/- 0.01,formation (28.4 +/- 2.3)%] and He group [A:0.30 +/- 0.01,formation (23.5 +/- 2.7)%], meanwhile the He group was the lowest (P<0.01). Positive expression of HIF-1alpha and VEGF in CO(2) and He artificial pneumoperitoneum up-regulated significantly as compared to control group(P<0.01), meanwhile the above expression was higher in CO(2) group (P<0.01). The G(0 )/G(1) ratio in CO(2) group was the lowest as compared to control group and He group (P<0.01), and G(0 )/G(1) ratio in He group was higher than that of control group(P<0.01). Aapoptosis rate in He group was the highest as compared with the other two groups(P<0.01). CONCLUSION: CO(2) pneumoperitoneum has stronger effect on the proliferation of colon carcinoma cell LS-174T as compared to He pneumoperitoneum in vitro.