Causal associations of cytokines and growth factors with cholelithiasis: a bidirectional Mendelian randomization study.

BACKGROUND: It has been reported that patients with cholelithiasis may have changes in levels of cytokines and growth factors, while their causal relationships were still unclear. METHODS: This study was a bidirectional Mendelian randomization (MR) study. Datasets of 41 circulation cytokines and growth factors and the data on cholelithiasis were obtained. Six steps of strict instrumental variable filtration were set, and inverse-variance weighted analysis, MR-Egger regression, and weighted median test were used to identify the causal relationships. Benjamini-Hochberg method was used to adjust the P-values. RESULTS: After adjustments of P-values, four cytokines and growth factors were still causally associated with cholelithiasis significantly: interleukin 2 receptor alpha (adjusted P: 4.59E-02), interleukin 8 (adjusted P: 1.09E-02), monocyte-specific chemokine 3 (adjusted P: 2.73E-04), and stem cell factor (adjusted P: 2.73E-04). In the reverse MR analysis, no significant causal relationship was detected after adjustment. CONCLUSIONS: Four cytokines and growth factors, including interleukin 2 receptor alpha, interleukin 8, monocyte-specific chemokine 3, and stem cell factor, were proven to relate to cholelithiasis causally and unidirectionally.

Long noncoding RNA CCAT2 functions as a competitive endogenous RNA to regulate FOXC1 expression by sponging miR-23b-5p in lung adenocarcinoma.

Long noncoding RNA (lncRNA) may regulate the process of tumor formation. Although lncRNA CCAT2 has been identified as a key point in many diseases, its pathophysiological mechanism in lung adenocarcinoma remains unknown. We measured the expression level of CCAT2 in lung adenocarcinoma cells and normal lung epithelial cell line BEAS-2B by quantitative real-time polymerase chain reaction (qRT-PCR). As well, cell migration and proliferation were detected by transwell detection and CCK8 assay. At the same time, the new target point of CCAT2 was confirmed with bioinformatics analysis and dual-luciferase reporter assay. In addition, potential mechanisms were studied by Western blot analysis and RNA immunoprecipitation (RIP) analysis. The expression of CCAT2 was upregulated obviously in lung adenocarcinoma cells. Cell function analysis showed that upregulation of CCAT2 significantly promoted cell proliferation and migration, and reduction of CCAT2 inhibited cell migration and proliferation. In addition, CCAT2 positively regulated the expression of FOXC1 by competitive binding with miR-23b-5p. These findings indicated that CCAT2 may act as a competitive endogenous RNA (ceRNA) to regulate FOXC1 expression by competitively binding miR-23b-5p in lung adenocarcinoma.

Mechanism of TRIM25 mediated ubiquitination of metastasis associated protein (MTA) 1 in normal liver cells.

Ninety percent of all cancer related deaths happen due to metastatic progression. One important protein facilitating metastatic progression in hepatocellular carcinoma (HCC) is the metastasis associated 1 protein (MTA-1). We have earlier shown that in the context of HCC and normal liver cell lines, HuH6 and THLE-2, respectively. MTA-1 protein is actively stabilized in HCC cell lines and actively degraded in normal liver cells. We had also shown that TRIM25 is the E3 ligase that interacts with and degrades MTA-1 protein in normal liver cells. However, the exact mechanism by which TRIM25 degrades MTA-1 protein has still not been elucidated. In the study, we used both in situ prediction algorithms and mass spectrometry based post-translational modification analysis to map the lysine residues in MTA-1 that are polyubiquitinated. Whereas UbPred algorithm revealed a combination of medium and low confidence sites, it revealed only one high confidence lysine (K98) residue. The hCKSAAP_UbSite algorithm also predicted K98 site. Mass spectrometry analysis also showed that K98 has ubiquitin modification. Immunofluorescence analysis showed that in normal liver cell line, THLE-2, which has high expression of TRIM25, ectopically expressed FLAG-tagged wild-type MTA-1 was actively degraded, but the K98R mutant MTA-1 was not. In vitro ubiquitination assay using recombinant wild-type and K98R mutant MTA-1 confirmed that MTA-1 is poly-ubiquitinated at K98 residue by TRIM25. The K98R mutant had a longer half-life than wild-type MTA-1 protein in an in vitro protein stability assay. We establish that TRIM25 ubiquitinates MTA-1 at lysine 98 and degrades it normal liver cells.

The E3 ligase for metastasis associated 1 protein, TRIM25, is targeted by microRNA-873 in hepatocellular carcinoma.

Tumor metastasis accounts for 90% of all cancer-related deaths. Epithelial to mesenchymal transition (EMT) considered to be centrally important in acquired resistance to chemotherapy and in progression of tumors to secondary organs. One of the important mediators of metastatic progression in hepatocellular carcinoma (HCC) is the metastasis associated protein 1 (MTA-1). We have earlier shown that in the context of HCC and normal liver cell lines, MTA-1 protein is actively stabilized in HCC cell lines and actively degraded in normal liver cells. We have also shown that TRIM25 is the E3 ligase that interacts with and degrades MTA-1 protein. The identity of the factor regulating expression of TRIM25 in normal liver cells and HCC is unknown. In the current work we elucidate that microRNA (miR)- 873 targets TRIM25 in HCC cells. Both metagenomic analysis and quantification of miR-873 and TRIM25 in 25 HCC patients revealed an inverse correlation between the two in HCC patients with high miR-873 and low TRIM25 expression, respectively. The expression pattern was mimicked in the normal liver cells THLE-2 and the HCC cell line, HuH6. In vitro luciferase reporter assays confirmed TRIM25 as the target of miR-873. Transient transfection of HuH6 cells with an anti-miR-873 antagomir significantly decreased both transwell motility in these cells. Furthermore, in in vivo xenograft assays treatment with anti-miR-873 antagomir significantly decreased hepatic nodules formation. Cumulatively, our data indicate that suppression of TRIM25 expression by high levels of miR-873 dictates MTA1 protein upregulation in HCC.

The ubiquitin ligase TRIM25 inhibits hepatocellular carcinoma progression by targeting metastasis associated 1 protein.

Metastasis associated 1 protein (MTA1) is one of the prime facilitators of metastatic progression in all solid tumors including hepatocellular carcinoma (HCC). However, the underlying regulatory mechanism of MTA1 expression in HCC is not clear. In this study, we evaluated MTA1 transcript and protein expression in HCC and normal hepatic cell lines. The results revealed that MTA1 protein expression had a significantly increase in HCC cell line, HuH6, compared with that in normal hepatic cell line, THLE-2. Determination of protein half-life using cycloheximide (CHX) treatment did not reveal any statistically significant difference in protein turn-over rates between THLE-2 (3.3 ± 0.25 h) and HuH6 (3.6 ± 0.15 h) cell lines. MTA1 protein level was stabilized in THLE-2 cells after treatment with MG-132 to levels similar to those observed in HuH6 cells. Mass spectrometric analysis of FLAG immunoprecipitates of FLAG-MTA1 transfected THLE-2 cells after MG-132 treated revealed candidate ubiquitin ligases that were interacting with MTA1. RNAi-mediated silencing of each prospective ubiquitin ligase in THLE-2 cells indicated that knockdown of TRIM25 resulted in stabilization of MTA1 protein, indicating TRIM25 as a putative E3 ligase for MTA1. Coimmunoprecipitation of FLAG-tagged MTA1, but not IgG, in MG-132 treated and untreated THLE-2 cells cotransfected with either FLAG-MTA1 or Myc-TRIM25 revealed robust polyubiquitinated MTA1, confirming that the TRIM25 is the ubiquitin ligase for MTA1 degradation. Overexpression of TRIM25 in HuH6 and RNAi mediated silencing of TRIM25 in THLE-2 cells inhibited and increased the cell migration and invasion, respectively. Analysis of The Cancer Genome Atlas data for assessment of TRIM25 transcript level and MTA1 protein expression in 25 HCC patients confirmed an inverse correlation between the expression of TRIM25 and MTA1. Cumulatively, our data reveal a novel mechanism of post-translational to regulate MTA1 expression in normal hepatic cells, which is repressed in HCC. © 2017 IUBMB Life, 69(10):795-801, 2017.

Expression of netrin-1 receptors in retina of oxygen-induced retinopathy in mice.

BACKGROUND: Netrin-1 has been reported to promote retinal neovascularization in oxygen-induced retinopathy (OIR). However, netrin-1 receptors, which may mediate netrin-1 action during retinal neovascularization, have not been characterized. In this study, we investigated netrin-1 receptor subtype expression and associated changes in the retinas of mice with OIR. METHODS: C57BL/6J mice were exposed to 75±2% oxygen for 5 days and then returned to normal air to induce retinal neovascularization. Reverse transcriptase polymerase chain reaction (RT-PCR) and Western blot were used to examine the expression of netrin-1 receptor subtypes in the mouse retinas. Double staining of netrin-1 receptor subtypes and isolectin B4 was used to determine the location of the netrin-1 receptor subtypes in the retinas. Inhibition of retinal neovascularization was achieved by UNC5B shRNA plasmid intravitreal injection. Retinal neovascularization was examined by fluorescein angiography and quantification of preretinal neovascular nuclei in retinal sections. RESULTS: RT-PCR results showed that, except for UNC5A, netrin-1 receptor subtypes UNC5B, UNC5C, UNC5D, DCC, neogenin, and A2b were all expressed in the retinas of OIR mice 17 days after birth. Western blots showed that only UNC5B expression was significantly increased on that day, and immunofluorescence results showed that only UNC5B and neogenin were expressed in retinal vessels. Treatment of OIR mice with the UNC5B shRNA plasmid dramatically reduced neovascular tufts and neovascular outgrowth into the inner limiting membrane. CONCLUSIONS: UNC5B may promote retinal neovascularization in OIR mice.

[Pre-alarming apparatus for earthquake based on mid-infrared trace methane detection].

With the rapid development of gas observation technology in seismic fracture zone, in order to accurately predict the earthquake, and reduce the people's lives and property losses caused by earthquake, a mid-infrared methane sensor was designed and developed, which is based on the microscopic relation between methane release and earthquake fissures on the crustal rocks. This instrument utilizes quantum cascaded laser (QCL) operating at 7.65 µm, combined with MIR multipass herriott cell with 76 m absorption path length to obtain low detection sensitivity down to 40 nmol x mol(-1) level in 4s acquisition time. Meanwhile, to decrease the primary noise source (1/f noise), semiconductor laser frequency modulation of direct absorption technology was utilized to obtain gas detection limitation as low as 5 nmol x mol(-1) (40 s acquiring time). In field experiments, controllable vibrator was used as vibration source, a number of trace methane detectors were placed with 100 m distance interval to carry out the dynamic measurement of methane concentration on the ground surface at different distances from the vibration source. Experimental results show that the instrument can monitor the release of underground methane before the earthquake and provide a novel measure as a pre-alarming for earthquake.

MG132 alleviates liver injury induced by intestinal ischemia/reperfusion in rats: involvement of the AhR and NFκB pathways.

BACKGROUND: MG132 is a potent antioxidant and has been reported to play a protective role in ischemia/reperfusion (I/R) of many organs. Recent studies have shown that the Aryl hydrocarbon receptor (AhR) may play a beneficial role in I/R of many organs and an AhR agonist has been implicated in an anti-inflammatory role. MG132 might function as an AhR agonist through proteasome inhibition, possibly through the inhibition of NFκB. Herein, we hypothesized that MG132 may play a protective role in liver injury induced by intestinal I/R and we analyzed the expression behavior of AhR and NFκB to determine whether the two factors play a role in intestinal I/R. MATERIALS AND METHODS: Thirty-two Sprague-Dawley rats were divided into four groups: control, I/R, MG132 control, and MG132 pretreatment. The I/R and MG132 pretreatment groups were subjected to mesenteric arterial ischemia for 1 h and reperfusion for 3 h. The control and MG132 control groups underwent surgical preparation including isolation of the superior mesenteric artery (SMA) without occlusion. The MG132 control and MG132 pretreatment groups were subjected to intraperitoneal administration of 0.5 mg/kg MG132 30 min before surgery. We collected serum specimens to measure TNF-α, IL-6, liver tissue levels of malondialdehyde (MDA), AhR, and cyp1a2; NFκB, IκBα, and ICAM-1 were also tested. Histologic changes of liver and intestine were subsequently evaluated. RESULTS: Compared with the control group, significant increases in MDA, NFκB, and ICAM-1 levels were accompanied by decreases in AhR, cyp1a2, and IκBα expression in the liver in the I/R group, which is consistent with liver and intestinal tissue injury. MG132 blocked the alterations of the indicators above. There were no changes in the MG132 control group compared with the control group in the indicators above. CONCLUSIONS: This study demonstrated that MG132 has a significant effect in protection against liver injury induced by intestinal I/R, which may be due to modulation of the AhR and NFκB pathways.

Caveolin-1 expression regulates blood-retinal barrier permeability and retinal neovascularization in oxygen-induced retinopathy.

BACKGROUND: Caveolin-1 expression correlates with the permeability of endothelial barriers and angiogenesis. However, the role of caveolin-1 in retinal neovascularization remains unknown. We evaluated the effect of caveolin-1 on the blood-retina barrier and retinal neovascularization in a murine model of oxygen-induced retinopathy. METHODS: Starting at postnatal day 7, mice were exposed to 75 ± 5% oxygen for 5 days and then returned to room air conditions to induce retinal neovascularization. Effects on blood-retina barrier were evaluated by Western blot analysis of extravasated albumin in the retina. Retinal neovascularization morphology was studied by fluorescence angiography and was quantified by counts of the endothelial nuclei that protruded into the vitreous cavity. Reverse transcription-polymerase chain reaction and Western blot analysis was used to examine retinal expression levels of caveolin-1. siRNA against caveolin-1 was injected intravitreally in the oxygen-induced retinopathy models. Effects on caveolin-1 mRNA and protein, and retinal neovascularization were assessed as described above. RESULTS: Caveolin-1 expression was found to increase during hypoxia and overexpression of caveolin-1 correlated with the appearance of extravascular albumin. Caveolin-1 siRNA reduced caveolin-1 mRNA and protein levels by 47.94% and 54.76%, respectively. Furthermore, caveolin-1 siRNA inhibition reduced retinal neovascularization by 51.3% and reduced albumin leakage by 56.32%. CONCLUSIONS: Caveolin-1 may play an important role in induction of retinal neovascularization. SiRNA against caveolin-1 can inhibit experimental retinal hyperpermeability and neovascularization. Therefore, the inhibition of caveolin-1 may be a powerful and novel therapeutic tool for the treatment of ischaemia-induced retinal diseases.

Overexpression of Gli1 in cancer interstitial tissues predicts early relapse after radical operation of breast cancer.

OBJECTIVE: To investigate whether Gli1 expression is important in relapse after radical operation of breast cancer. METHODS: Using immunohistochemistry, Gli1 expression was analyzed in human primary breast cancer (n=284) and paracancerous tissues (n=20), and also in local lymph nodes (n=28) and metastatic lymph nodes (n=28). RESULTS: Initial analysis of Gli1 expression in a small cohort of 20 breast tumors and their paracancerous tissues showed a tendency towards Gli1 overexpression in breast cancer tissues (P<0.001). Further, Gli1 expression in 284 breast cancer tissue samples was analyzed and a significant correlation was found between increased expression of nuclear Gli1 and unfavorable recurrence-free survival (RFS) (P<0.05). The nuclear expression of Gli1 in metastatic lymph nodes following relapse after radical operation was much higher than that in the local lymph nodes of primary carcinoma (P<0.05). Most interestingly, the expression of Gli1 was much higher in the interstitial tissues of the relapsed group than of the non-relapsed group (P<0.001). CONCLUSIONS: Breast cancer shows a high prevalence of Gli1 expression, which is significantly correlated with aggressive features and unfavorable RFS. Nuclear Gli1 overexpression, especially in the interstitial tissues, signified early relapse after radical operation of breast cancer.

Netrin-1 overexpression in oxygen-induced retinopathy correlates with breakdown of the blood-retina barrier and retinal neovascularization.

PURPOSES: Recent research has shown netrin-1 to promote neovascularization. We evaluate the expression of netrin-1 during retinal neovascularization in a murine model of oxygen-induced retinopathy. METHODS: C57BL/6J mice were exposed to 75 ± 5% oxygen for 5 days and returned to room air to induce retinal neovascularization. Retinal neovascularization was observed by fluorescence angiography and was quantified by counting the endothelial nuclei protruding into the vitreous cavity after hematoxylin-eosin staining. RT-PCR and Western blot analyses were used to determine retinal netrin-1 mRNA and protein levels at postnatal days (PN) 13, 15 and 17. RESULTS: In fluorescence angiograms, irregular neovascularization and fluorescein leakage were observed surrounding the unperfused areas in the hypoxic group. The hypoxic group had, on average, 50.70 ± 4.56 neovascular nuclei protruding into the vitreous body, while similar nuclei were absent in the control group. Compared to the normoxic group, there were significant increases in both retinal netrin-1 mRNA and protein levels in the hypoxic group at PN13, PN15 and PN17. CONCLUSION: The netrin-1 level increases in murine retina under hypoxia and may be key in inducing retinal neovascularization.

Protein kinase B (akt) promotes pathological angiogenesis in murine model of oxygen-induced retinopathy.

Akt, or protein kinase B, is an important signaling molecule that modulates many cellular processes such as cell growth, survival, and metabolism. However, the vivo roles and effectors of Akt in retinal angiogenesis are not explicitly clear. We therefore detected the expression of Akt using Western blotting or RT-PCR technologies in an animal model of oxygen-induced retinopathy, and investigated the effects of recombinant Akt on inhibiting vessels loss and Akt inhibitor on suppressing experimental retinal neovascularization in this model. We showed that in the hyperoxic phase of oxygen-induced retinopathy, the expression of Akt was greatly suppressed. In the hypoxic phase, the expression of Akt was increased dramatically. No significant differences were found in normoxic groups. Compared with control groups, administration of the recombinant Akt in the first phase of retinopathy markedly reduced capillary-free areas, while the administration of the Akt inhibitor in the second phase of retinopathy significantly decreased retinal neovascularization but capillary-free areas. These results indicate that Akt play a critical role in the pathological process (vessels loss and neovascularization) of mouse model of oxygen-induced retinopathy, which may provide a valubale therapeutic tool for ischemic-induced retinal diseases.

Circular RNA AKT3 governs malignant behaviors of esophageal cancer cells by sponging miR-17-5p.

BACKGROUND: Recent studies have demonstrated that circular RNA AKT3 (circAKT3) plays a crucial role in regulating the malignant phenotypes of tumor cells. However, the potential effects of circAKT3 on esophageal cancer have not been investigated. AIM: To illuminate the role of circAKT3 in malignant behaviors of esophageal cancer cells and its underlying mechanism. METHODS: Clinical samples were collected to detect the expression of circAKT3. The role of circAKT3 in proliferation, migration, invasion, and apoptosis of esophageal cancer cells was evaluated using Cell Counting Kit-8, wound healing assays, Transwell assays, and fluorescence analysis, respectively. The target of circAKT3 was screened and identified using an online database and luciferase reporter assay. A xenograft nude mouse model was established to investigate the role of circAKT3 in vivo. RESULTS: In vitro assays showed that proliferative, migratory, and invasive capacities of esophageal cancer cells were significantly enhanced by circAKT3 overexpression. Furthermore, miR-17-5p was screened as the target of circAKT3, and miR-17-5p antagonized the effects of circAKT3 on esophageal cancer cells. Moreover, we identified RHOC and STAT3 as the direct target molecules of miR-17-5p, and circAKT3 facilitated expression of RHOC and STAT3 by inhibiting miR-17-5p. In vivo assays showed circAKT3 knockdown inhibited growth of esophageal cancer. CONCLUSION: CircAKT3 contributed to the malignant behaviors of esophageal cancer in vitro and in vivo by sponging miR-17-5p thus providing a potential target for treatment of esophageal cancer.

The microstructures and mechanical properties of nanocrystalline Li2SiO3: molecular dynamics simulations.

The microstructures and mechanical properties of nanocrystalline Li2SiO3 have been investigated via molecular dynamics calculations. The results indicate that the mean atomic mass densities of nanostructured Li2SiO3 with different mean grain size are slightly lower than that of ordinary crystal Li2SiO3. Interestingly, a significant anti-Hall-Petch effect between yield stress and average grain size is observed in the tensile deformation simulation of the samples. In fact, the curve changes linearly until the strain reaches approximately 0.016-0.018. Next, when the strain is between 0.27 and 0.38, the stress of the sample has a small peak in the plastic flow region. Then, all the samples will begin to fracture at a strain of about 0.39-0.41. Moreover, due to the influence of grain boundary sliding and grain rotation, there are a few dislocations in the samples with the small average grain sizes, highlighting the strong influence of the mechanical properties on the overall tensile deformation of the samples.

Protective effect of carnosol on lung injury induced by intestinal ischemia/reperfusion.

PURPOSE: Carnosol is a phenolic diterpene that has potent antioxidant and anti-inflammatory activities. The purpose of this study was to investigate the preconditioning effects of carnosol on lung injury induced by intestinal ischemia/reperfusion (II/R). METHODS: Rats were divided into control, II/R, and carnosol groups. The II/R model was established by clamping the superior mesenteric artery for 1 h and reperfusion at 2, 4, and 6 h after ischemia. The carnosol group received 3 mg/kg carnosol intraperitoneally 1 h before the operation. The rats were then euthanized, and blood and lung specimens were obtained for analysis. RESULTS: The II/R induced lung injury, characterized by histological changes and significant increasing of bronchoalveolar lavage fluid protein. The activity of lung tissue superoxide was weakened, the tissue myeloperoxidase activity and serum interleukin-6 level increased significantly in II/R groups. A strong positive expression of lung intercellular adhesion molecule-1 (ICAM-1) and nuclear factor kappa B (NF-kappaB) were observed. Pretreatment with carnosol markedly reduced lung injury by increasing the tissue superoxide activity and decreasing the myeloperoxidase activity and interleukin-6 level, which was parallel to the decreased expression of ICAM-1 and NF-kappaB. CONCLUSION: Carnosol was able to ablate lung injury induced by II/R, partly attributed to the inhibition of NF-kappaB activation.

[Effects of Gastric bypass surgery on the apoptosis of islet ß-cells in type 2 nonobese diabetic (NOD) rats and its mechanism].

OBJECTIVE: To investigate the effects of Gastric bypass surgery on the apoptosis of islet ß-cells in type 2 nonobese diabetic (NOD) rats and its mechanisms. METHODS: Seventy-two 8-week-old GK rats were randomly divided into four groups:operation group (group O, n = 18), sham operation group (group S, n = 18), diet control group (group F, n = 18) and control group (group C, n = 18). The levels of fasting, postprandial blood glucose, insulin and glucagon-like peptide-1 (GLP-1) were measured and compared among the 4 groups before the operation and at 1, 2, 4 and 8 weeks following the operation. The blood samples were collected at 2, 4 and 8 weeks after the operation for the measurement of postprandial blood glucose, and then the rats in batches (6 rats in each group) were decapitated to retrieve the pancreas. The apoptosis of the islet ß-cells was detected by using TUNEL assay, and the expression of apoptosis-related proteins Bcl-2, Bax was measured with immunohistochemistry. RESULTS: As for group O, the fasting blood glucose level decreased from (16.2 ± 0.8) mmol/L before the operation to respectively (9.2 ± 0.6) mmol/L and (9.7 ± 0.7) mmol/L at 4 and 8 weeks after the operation; postprandial blood glucose decreased from (31.1 ± 1.1) mmol/L before the operation to respectively (13.1 ± 0.7) mmol/L and (12.3 ± 0.7) mmol/L at 4 and 8 weeks after the operation. Fasting insulin level increased from (28.0 ± 1.2) mU/L before the operation to respectively (62.8 ± 1.9) mU/L and (61.7 ± 1.4) mU/L at 4 and 8 weeks after the operation; and at 4 and 8 weeks after the operation postprandial insulin level was (77.4 ± 1.1) mU/L and (77.1 ± 1.0) mU/L. At 2 weeks from the operation, the fasting GLP-1 in group O increased from (10.7 ± 1.0) pmol/L to (13.5 ± 0.8) pmol/L, and respectively to (26.1 ± 0.9) pmol/L and (25.3 ± 1.2) pmol/L at 4 and 8 weeks after the operation. The differences in the above-mentioned items before and after the operation were all significant in group O (P < 0.05), and the differences in the items among group O and the other three groups (P < 0.05) were all significant as well. In group O, the apoptosis rate of pancreatic islet cell decreased to (5.9 ± 0.7)% at 4 weeks from the operation, and (6.3 ± 1.1)% at 8 weeks from the operation (P < 0.05). The expression of Bcl-2 protein in group O was 31.3 ± 1.5, 35.7 ± 1.0 and 35.8 ± 0.8 at 2, 4 and 8 weeks post operation, which was significantly higher in statistics than those of the same time point in the other three groups (P < 0.05). The expression of Bax protein in group O was 13.3 ± 0.9, 10.8 ± 0.9 and 10.9 ± 1.1 at 2, 4 and 8 weeks from the operation, which was significantly lower in statistics than those of the same time point in the other three groups (P < 0.05). CONCLUSIONS: Gastric bypass surgery can significantly reduce the blood glucose level and promote the secretion of GLP-1, and therefore inhibit the apoptosis of the islet ß cells in diabetic rats through the Bcl-2 pathway.

Effects of long non-coding RNA Opa-interacting protein 5 antisense RNA 1 on colon cancer cell resistance to oxaliplatin and its regulation of microRNA-137.

BACKGROUND: The incidence of colon cancer (CC) is currently high, and is mainly treated with chemotherapy. Oxaliplatin (L-OHP) is a commonly used drug in chemotherapy; however, long-term use can induce drug resistance and seriously affect the prognosis of patients. Therefore, this study investigated the mechanism of Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) on L-OHP resistance by determining the expression of OIP5-AS1 and microRNA-137 (miR-137) in CC cells and the effects on L-OHP resistance, with the goal of identifying new targets for the treatment of CC. AIM: To study the effects of long non-coding RNA OIP5-AS1 on L-OHP resistance in CC cell lines and its regulation of miR-137. METHODS: A total of 114 CC patients admitted to China-Japan Union Hospital of Jilin University were enrolled, and the expression of miR-137 and OIP5-AS1 in tumor tissues and corresponding normal tumor-adjacent tissues was determined. The influence of OIP5-AS1 and miR-137 on the biological behavior of CC cells was evaluated. Resistance to L-OHP was induced in CC cells, and their activity was determined and evaluated using cell counting kit-8. Flow cytometry was used to analyze the apoptosis rate, Western blot to determine the levels of apoptosis-related proteins, and dual luciferase reporter assay combined with RNA-binding protein immunoprecipitation to analyze the relationship between OIP5-AS1 and miR-137. RESULTS: OIP5-AS1 was up-regulated in CC tissues and cells, while miR-137 was down-regulated in CC tissues and cells. OIP5-AS1 was inversely correlated with miR-137 (P < 0.001). Silencing OIP5-AS1 expression significantly hindered the proliferation, invasion and migration abilities of CC cells and markedly increased the apoptosis rate. Up-regulation of miR-137 expression also suppressed these abilities in CC cells and increased the apoptosis rate. Moreover, silencing OIP5-AS1 and up-regulating miR-137 expression significantly intensified growth inhibition of drug-resistant CC cells and improved the sensitivity of CC cells to L-OHP. OIP5-AS1 targetedly inhibited miR-137 expression, and silencing OIP5-AS1 reversed the resistance of CC cells to L-OHP by promoting the expression of miR-137. CONCLUSION: Highly expressed in CC, OIP5-AS1 can affect the biological behavior of CC cells, and can also regulate the resistance of CC cells to L-OHP by mediating miR-137 expression.

MTA1 Promotes Hepatocellular Carcinoma Progression by Downregulation of DNA-PK-Mediated H1.2T146 Phosphorylation.

Global incidence and mortality associated with hepatocellular carcinoma (HCC) is steadily increasing. Metastasis-associated 1 (MTA1) can induce tumorigenesis and metastatic progression in HCC. However, the mechanistic details of MTA1-mediated regulation of HCC has not been completely defined. Epigenetic histone modification is closely related to tumor development. Histone cluster 1 H1 family member c (H1.2) is important for epigenetic histone modification and chromatin remodeling; however, whether it has a role in HCC tumorigenesis is not known. In the current study, we confirmed that MTA1 promoted HCC cell growth and migration. Our results further show that MTA1 inhibited the phosphorylation of histone cluster 1 H1 family member c (H1.2) at threonine-146 residue (T146) (H1.2T146ph). MTA1 inhibited H1.2T146ph by mediating proteasomal degradation of the DNA protein kinase (DNA-PK). Pharmacological inhibition of proteasomal degradation of DNA-PK or genetic ablation of E3 ligase mouse double minute 2 (MDM2) rescued expression of DNA-PK, and subsequent phosphorylation of H1.2. MTA1's role in HCC was inhibited by ectopic expression of H1.2T146ph in HCC cell lines. Our results showed that H1.2T146ph can bind to MTA1 target genes. Collectively, our study confirms that MTA1 functions as an oncogene and promotes HCC progression. The epigenetic histone modifier H1.2T146ph exerts critical role in the regulation of MTA1-induced tumorigenesis. MTA1 regulates posttranslational activation of H1.2 by regulating the cognate kinase, DNA-PK, via the ubiquitin proteasome system. MTA1 expression was inversely correlated to both DNA-PK and phosphorylated H1.2 in HCC tissue specimens compared to tumor adjacent normal hepatic tissue, revealing that the MTA1/MDM2/DNA-PK/H1.2 is an important therapeutic axis in HCC.

PTEN-induced kinase 1-induced dynamin-related protein 1 Ser637 phosphorylation reduces mitochondrial fission and protects against intestinal ischemia reperfusion injury.

BACKGROUND: Intestinal ischemia reperfusion (I/R) occurs in various diseases, such as trauma and intestinal transplantation. Excessive reactive oxygen species (ROS) accumulation and subsequent apoptotic cell death in intestinal epithelia are important causes of I/R injury. PTEN-induced putative kinase 1 (PINK1) and phosphorylation of dynamin-related protein 1 (DRP1) are critical regulators of ROS and apoptosis. However, the correlation of PINK1 and DRP1 and their function in intestinal I/R injury have not been investigated. Thus, examining the PINK1/DRP1 pathway may help to identify a protective strategy and improve the patient prognosis. AIM: To clarify the mechanism of the PINK1/DRP1 pathway in intestinal I/R injury. METHODS: Male C57BL/6 mice were used to generate an intestinal I/R model via superior mesenteric artery occlusion followed by reperfusion. Chiu's score was used to evaluate intestinal mucosa damage. The mitochondrial fission inhibitor mdivi-1 was administered by intraperitoneal injection. Caco-2 cells were incubated in vitro in hypoxia/reoxygenation conditions. Small interfering RNAs and overexpression plasmids were transfected to regulate PINK1 expression. The protein expression levels of PINK1, DRP1, p-DRP1 and cleaved caspase 3 were measured by Western blotting. Cell viability was evaluated using a Cell Counting Kit-8 assay and cell apoptosis was analyzed by TUNEL staining. Mitochondrial fission and ROS were tested by MitoTracker and MitoSOX respectively. RESULTS: Intestinal I/R and Caco-2 cell hypoxia/reoxygenation decreased the expression of PINK1 and p-DRP1 Ser637. Pretreatment with mdivi-1 inhibited mitochondrial fission, ROS generation, and apoptosis and ameliorated cell injury in intestinal I/R. Upon PINK1 knockdown or overexpression in vitro, we found that p-DRP1 Ser637 expression and DRP1 recruitment to the mitochondria were associated with PINK1. Furthermore, we verified the physical combination of PINK1 and p-DRP1 Ser637. CONCLUSION: PINK1 is correlated with mitochondrial fission and apoptosis by regulating DRP1 phosphorylation in intestinal I/R. These results suggest that the PINK1/DRP1 pathway is involved in intestinal I/R injury, and provide a new approach for prevention and treatment.

Integrative analysis of the inverse expression patterns in pancreas development and cancer progression.

BACKGROUND: As the malignant tumor, pancreatic cancer with a meager 5-years survival rate has been widely concerning. However, the molecular mechanisms that result in malignant transformation of pancreatic cells remain elusive. AIM: To investigate the gene expression profiles in normal or malignant transformed pancreas development. METHODS: MaSigPro and ANOVA were performed on two pancreas development datasets downloaded from the Gene Expression Omnibus database. Six pancreatic cancer datasets collected from TCGA database were used to establish differentially expressed genes related to pancreas development and pancreatic cancer. Moreover, gene clusters with highly similar interpretation patterns between pancreas development and pancreatic cancer progression were established by self-organizing map and singular value decomposition. Additionally, the hypergeometric test was performed to compare the corresponding interpretation patterns. Abnormal regions of metabolic pathway were analyzed using the Sub-pathway-GM method. RESULTS: This study established the continuously upregulated and downregulated genes at different stages in pancreas development and progression of pancreatic cancer. Through analysis of the differentially expressed genes, we established the inverse and consistent direction development-cancer pattern associations. Based on the application of the Subpathway-GM analysis, we established 17 significant metabolic sub-pathways that were closely associated with pancreatic cancer. Of note, the most significant metabolites sub-pathway was related to glycerophospholipid metabolism. CONCLUSION: The inverse and consistent direction development-cancer pattern associations were established. There was a significant correlation in the inverse patterns, but not consistent direction patterns.