Knockdown of Angiopoietin-like protein 4 suppresses the development of colorectal cancer.

Colorectal cancer, is the growth of cancer cells in the part of the colon. Angiopeptin is one of the growth factors in the human body that is particularly effective in the regulatory process. In this research, the regulatory role and its mechanism of Angiopoietin-like protein 4 (ANGPTL4) in colorectal cancer (CRC) metastasis, has been studied. Protein expression of ANGPLT4 was analyzed by immunohistochemistry in tumor samples and adjacent normal specimens of 40 patients with CRC cancer of various phases. A gene knockout test was conducted, two effective siRNA of ANGPTL4, named siRNA1 and siRNA2, were constructed and transfected into two CRC cell lines SW480 and HT-29 to block the expression of ANGPTL4. QRT-PCR and western blotting were used to validate the knockdown efficiency of the mRNA and proteins. Based on the results, the protein expression of ANGPTL4 was increased in human CRC tissues with the development of CRC. Knockdown of ANGPTL4 by siRNA in SW480 and HT-29 cells in vitro inhibited cell proliferation, promoted cell apoptosis, and suppressed the ability of cell migration and invasion. Besides, the sensitivity of CRC cells to Cisplatin was increased in the low ANGPTL4 expression group. ANGPTL4 might be a new potential therapeutic target for patients with CRC.

LPS preconditioning ameliorates intestinal injury in a rat model of hemorrhagic shock.

OBJECTIVE AND DESIGN: Previous studies indicate that endotoxin preconditioning may decrease the inflammatory response and alleviate intestinal mucosal damage caused by sepsis. However, it is not known whether preconditioning with endotoxin might protect the intestinal mucosa after hemorrhagic shock. In this study, we investigated the effect of lipopolysaccharide (LPS) preconditioning on the intestinal mucosa following hemorrhagic shock in a rat model. Given that intestinal toll-like receptor 4 (TLR4) signaling is exaggerated in response to LPS, we further investigated the role of TLR4 signaling in endotoxin tolerance. METHODS: Animals were pre-treated with intra-peritoneal Escherichia coli LPS for 5 days prior to hemorrhagic shock. Animals were bled to achieve a mean arterial pressure (MAP) of 35-40 mmHg, then resuscitated with Ringer solution and the heparinized shed blood to maintain MAP between 90 and 100 mmHg. The distal ileum was harvested after resuscitation and graded for mucosal damage. TNF-α, TLR4, cleaved caspase-3, and intestinal trefoil factor 3 (TFF3) levels were measured at different time points. RESULTS: Pretreatment with LPS significantly reduced intestinal mucosal damage and protein levels of cleaved caspase-3. Furthermore, animals pre-treated with LPS experienced reduction of TNF-α and increased mucosal expression of TFF3. LPS tolerance was associated with reduced TLR4 expression. CONCLUSIONS: Endotoxin preconditioning can lessen the effects of ischemia and reperfusion injury in intestinal mucosa of a rat model with hemorrhagic shock. It is hypothesized that this effect is mediated via inhibition of TLR4 over-expression.

Tumor deposit indicates worse prognosis than metastatic lymph node in gastric cancer: a propensity score matching study.

BACKGROUND: The prognostic value of tumor deposit (TD) in gastric cancer is controversial. This study aims to investigate the prognostic value of TD. METHODS: The consecutive patients diagnosed with gastric cancer from October 2007 to October 2012 were selected. The patients were divided by whether they suffered TD into two groups. The basic data were comparable between the two groups after propensity score matching (PSM), then survival analysis [overall survival (OS) and cancer-specific survival (CSS)] was applied in two groups. After that, all the patients were divided by pN staging and survival analysis were applied in each subgroup. At last, all patients were divided into TD group, pN1 stage group, pN2 stage group, pN3a, and pN3b stage group, OS and CSS were compared between them. Multivariable competing risk analyses tested association of TD with OS and CSS, before and after PSM. RESULTS: Eight hundred and three patients were concluded. After PSM, 137 patients with TD and 274 patients without TD were selected, the 5-year OS and CSS rates of patients with TD were significantly worse than patients without TD (OS: 19.7% vs. 42.0%, P<0.001; CSS: 22.6% vs. 45.6%, P<0.001). In all patients' survival analysis, the 5-year OS and CSS rates of TD group were comparable with pN3a group (OS: 19.7% vs. 25.3%, P=0.221, CSS: 22.6% vs. 30.1%, P=0.092) and pN3b group (OS: 19.7% vs. 19.6% P=0.349, CSS: 22.6% vs. 23.5%, P=0.452). Meanwhile, on multivariable cox regression analyses, the presence of TD significantly reduces the OS and CSS of patients in gastric cancer. CONCLUSIONS: TD has a marked impact on the prognosis of gastric cancer. Even patients with TD had the same prognosis with pN3 stage.

Knockdown of angiopoietin-like 4 inhibits the development of human gastric cancer.

Human gastric cancer (GC) is the second most common cause of cancer-related deaths worldwide and is one of the most common metastatic cancers. Tumor proliferation, apoptosis, metastasis and invasion are important predictors of the invasiveness of GC and are key factors in cancer-induced death. Angiopoietin-like 4 (ANGPTL4) is a secreted protein that belongs to the angiopoietin (ANGPTL) family and is involved in the regulation of cancer metastasis. However, whether ANGPTL4 plays a role in the progression of GC remain unclear. In the present study, immunoreactivity of ANGPTL4 demonstrated that ANGPTL4 expression was upregulated in GC tissues with the development of GC. The siRNA targeting ANGPTL4 effectively knocked down ANGPTL4 in the SNU­1 and BGC823 cell lines at the mRNA and protein levels. Following ANGPTL4 downregulation, the proliferation and invasion abilities of GC cell lines were suppressed as determined by MTT and Transwell assays, and cell apoptosis level and sensitivity to cisplatin were increased as determined by flow cytometry and MTT assay. In conclusion, these findings suggest that ANGPTL4 may be a new potential therapeutic target for GC.

[Risk stratification and prognostic evaluation of patients with pulmonary thromboembolism].

OBJECTIVE: To explore the risk stratification and prognostic evaluation of pulmonary thromboembolism (PTE). METHODS: The clinical data of 46 patients suffering from PTE diagnosed by ventilation perfusion scan or spiral CT pulmonary angiography admitted to our hospital from January 2002 to December 2006 were analyzed retrospectively. RESULTS: The total mortality was 33% (15/46 cases). The mortality in the group whose cardiac troponin I was positive (n=11) was 82% (9/11 cases), 17% (6/35 cases)when troponin I was negative (n=35). The mortality in normal electrocardiogram (ECG) group (n=14) and abnormal group (n=32) was 7% (1/14 cases) and 44% (14/32 cases) respectively. The mortality in the group with right ventricular dilatation (right ventricular diastolic dimension/left ventricular diastolic dimension > or =0.6) as shown by echocardiography (n=20) and without right ventricular dilatation (n=26) right ventricular diastolic dimension/left ventricular diastolic dimension<0.6) was 55% (11/20 cases) and 15% (4/26 cases) respectively. The mortality in the group whose pulmonary arterial obstruction index shown by spiral CT pulmonary angiography <0.6 (n=19) and > or =0.6 (n=11) was 5% (1/19 cases) and 91% (10/11 cases) respectively. The mortality between above groups showed statically significant difference (all P<0.05). CONCLUSION: Cardiac troponin I, ECG, right ventricular dilatation by echocardiography and pulmonary arterial obstruction index by spiral CT pulmonary angiography may be taken as indices for risk stratification and prognostic evaluation of patients with PTE, and they may be helpful in optimizing treatment strategies.

miR-944 inhibits cell migration and invasion by targeting MACC1 in colorectal cancer.

Dysfunction of microRNAs (miRNAs) is strongly proved to participate in the pathogenesis and tumorigenicity of colorectal cancer (CRC). miR-944 was reported to play either oncogenic or tumor suppressive roles in human cancers. A recent study reported that the levels of miR-944 in recurrent CRC patients were evidently lower than that in non-recurrent cases, suggesting that miR-944 may function as a tumor suppressive miRNA in CRC. Yet, the clinical value and biological function of miR-944 remain rarely known in CRC. In the present study, we present that miR-944 level in CRC tissues is notably reduced compared to matched non-cancerous specimens. Its decreased level is evidently correlated with malignant clinical parameters and poor prognosis of CRC patients. Accordingly, the levels of miR-944 were obviously downregulated in CRC cells. Ectopic expression of miR-944 in CRC cells prominently inhibits the migration and invasion of tumor cells, while miR-944 knockdown increased these effects of CRC cells. Mechanically, miR-944 negatively regulated the metastasis-associated in colon cancer-1 (MACC1) abundance in CRC cells. Herein, MACC1 was found to be a downstream molecule of miR-944 in CRC. An inversely correlation between miR-944 and MACC1 was confirmed in CRC specimens. Furthermore, restoration of MACC1 expression could abrogate the anti-metastatic effects of miR-944 on CRC cells with enhanced cell migration and invasion. MACC1/Met/AKT signaling may be implicated with the function of miR-944 in CRC cells. Altogether, miR-944 potentially act as a prognostic predictor and a drug-target for CRC patients.

MicroRNA-520c enhances cell proliferation, migration, and invasion by suppressing IRF2 in gastric cancer.

Dysregulation of microRNA (miRNA) is actively involved in the development and progression of gastric cancer (GC). MiR-520c was previously found to be overexpressed in GC specimens and cells. However, the clinical significance of miR-520c and its biological function in GC remain largely unknown. Here, we found that miR-520c expression in GC tissues was significantly increased compared to normal adjacent gastric tissues. Its increased level was prominently correlated with poor clinical parameters and prognosis of GC patients. Accordingly, the expression of miR-520c was obviously elevated in GC cell lines as compared with gastric epithelial cells. Overexpression of miR-520c in N-87 cells significantly increased the proliferative ability, migration, and invasion of cancer cells, while miR-520c silencing suppressed MKN-45 cell proliferation, migration, and invasion in vitro. Mechanically, miR-520c inversely regulated interferon regulatory factor 2 (IRF2) abundance in GC cells. Herein, IRF2 was found to be a downstream target of miR-520c in GC. Furthermore, IRF2 was down-regulated in GC tissues compared to nontumor tissues. An inverse correlation between IRF2 and miR-520c expression was observed in GC cases. Taken together, miR-520c may serve as a prognostic predictor and a therapeutic target for GC patients.

Functional and morphological changes of the gut barrier during the restitution process after hemorrhagic shock.

AIM: To investigate the functional, morphological changes of the gut barrier during the restitution process after hemorrhagic shock, and the regional differences of the large intestine and small intestine in response to ischemia/reperfusion injury. METHODS: Forty-seven Sprague-Dawley rats with body weight of 250-300 g were divided into two groups: control group (sham shock n = 5) and experimental group (n = 42). Experimental group was further divided into six groups (n = 7 each) according to different time points after the hemorrhagic shock, including 0(th) h group, 1st h group, 3rd h group, 6th h group, 12th h group and 24th h group. All the rats were gavaged with 2 mL of suspension of lactulose (L) (100 mg/2 mL) and mannitol (M) (50 mg/each) at the beginning and then an experimental rat model of hemorrhagic shock was set up. The specimens from jejunum, ileum and colon tissues and the blood samples from the portal vein were taken at 0, 1, 3, 6, 12 and 24 h after shock resuscitation, respectively. The morphological changes of the intestinal mucosa, including the histology of intestinal mucosa, the thickness of mucosa, the height of villi, the index of mucosal damage and the numbers of goblet cells, were determined by light microscope and/or electron microscope. The concentrations of the bacterial endotoxin lipopolysaccharides (LPS) from the portal vein blood, which reflected the gut barrier function, were examined by using Limulus test. At the same time point, to evaluate intestinal permeability, all urine was collected and the concentrations of the metabolically inactive markers such as L and M in urine were measured by using GC-9A gas chromatographic instrument. RESULTS: After the hemorrhagic shock, the mucosal epithelial injury was obvious in small intestine even at the 0(th) h, and it became more serious at the 1st and the 3rd h. The tissue restitution was also found after 3 h, though the injury was still serious. Most of the injured mucosal restitution was established after 6 h and completed in 24 h. Two distinct models of cell death-apoptosis and necrosis-were involved in the destruction of rat intestinal epithelial cells. The number of goblet cells on intestinal mucosa was reduced significantly from 0 to 24 h (the number from 243+/-13 to 157+/-9 for ileum, 310+/-19 to 248+/-18 for colon; r = -0.910 and -0.437 respectively, all P<0.001), which was the same with the large intestine, but the grade of injury was lighter with the values of mucosal damage index in 3 h for jejunum, ileum, and colon being 2.8, 2.6, 1.2, respectively. The mucosal thickness and the height of villi in jejunum and ileum diminished in 1 h (the average height decreased from 309+/-24 to 204+/-23 microm and 271+/-31 to 231+/-28 microm, r = -0.758 and -0.659, all P<0.001; the thickness from 547+/-23 to 418+/-28 microm and 483+/-45 to 364+/-35 microm, r = -0.898 and -0.829, all P<0.001), but there was no statistical difference in the colon (F = 0.296, P = 0.934). Compared with control group, the urine L/M ratio and the blood LPS concentration in the experimental groups raised significantly, reaching the peak in 3-6 h (L/M: control vs 3 h vs 6 h was 0.029+/-0.09 vs 0.063+/-0.012 vs 0.078+/-0.021, r = -0.786, P<0.001; LPS: control vs 3 h vs 6 h was 0.09+/-0.021 vs 0.063+/-0.012 vs 0.25+/-0.023, r = -0.623, P<0.001), and it kept increasing in 24 h. CONCLUSION: The gut barrier of the rats was seriously damaged at the early phase of ischemic reperfusion injury after hemorrhagic shock, which included the injury and atrophy in intestinal mucosa and the increasing of intestinal permeability. Simultaneously, the intestinal mucosa also showed its great repairing potentiality, such as the improvement of the intestinal permeability and the recovery of the morphology at different phases after ischemic reperfusion injury. The restitution of gut barrier function was obviously slower than that of the morphology and there was no direct correlation between them. Compared with the small intestine, the large intestine had stronger potentiality against injury. The reduction of the amount of intestinal goblet cells by injury did not influence the ability of intestinal mucosal restitution at a certain extent and it appeared to be intimately involved in the restitution of the epithelium.

Repair of damaged intestinal mucosa in a mouse model of sepsis.

BACKGROUND: The intestine is not only the main target attacked by sepsis but also the vital organ which mediated sepsis. The recovery of the damaged intestinal barrier structure and function is related to the occurrence and outcome of multiple organ dysfunction syndrome (MODS). How to protect and reduce the damage of the intestinal mucosa and how to promote the reconstruction of the intestinal mucosa have been the important topics in sepsis for many years. This study aimed to investigate the influential factors of intestinal mucosal reconstruction after intestinal epithelial injury in vivo in a mouse model of sepsis. METHODS: Mice were subjected to cecal ligation and puncture (CLP) for induction of sepsis to assess intestinal mucosal damage, epithelial cell apoptosis, and transformed number of goblet cells, and to detect the concentration of TNF-α, IL-1 and TGF-ß1 and TFF3 (trefoil factor 3) expression in the small intestinal mucosa. All above were performed by HE staining, western blot, ELISA and immunohistochemistry respectively. The experimental animals were divided into a sepsis group and a sham-operation group. The animals with sepsis were separately killed at 6 (7 animals), 24 (7 animals) and 48 hours (7 animals) after CLP. RESULTS: Injured intestinal mucosa was observed in the 3 groups under a light microscope, in which damage scores in the 24-hour and 48-hour groups were higher than in the 6-hour group and no difference was found between the two groups. Moreover, less of goblet cells or other epithelial cells adjacent to the injured surface migrated into the wound to cover the denuded area. The number of goblet cells was substantially decreased in the three CLP groups compared with the sham-operation group. Protein levels of IL-1 and TNF-α were significantly increased by 3-4 fold at all time points when compared with the sham-operation group, and cleaved caspase-3 by 4 fold. Although TFF3 expression was modestly increased for 6 hours after the onset of CLP, it appeared to decline at 24 hours and 48 hours as shown by Western blot. A similar tendency was observed upon TGF-ß1, i.e. the protein level was not elevated at 24 hours and 48 hours, but increased modestly at 6 hours. CONCLUSIONS: Sepsis from CLP shows less restitution on the surface of injured intestinal mucosa. There is evidence that both constant inflammatory reaction and epithelial cell apoptosis may affect mucosal reestablishment of the intestine at the onset of sepsis. Mucosa after severe sepsis showed the state of high inflammation, and declined goblet cell function and mucosal reconstruction, which affected the repair of damaged intestinal barrier. Constant inflammatory reaction, and declined goblet cell function and mucosal reconstruction ability may affect the reestablishment of intestinal mucosa at the onset of sepsis.

Changes of the immunological barrier of intestinal mucosa in rats with sepsis.

BACKGROUND: Sepsis has become the greatest threat to in-patients, with a mortality of over 25%. The dysfunction of gut barrier, especially the immunological barrier, plays an important role in the development of sepsis. This dysfunction occurs after surgery, but the magnitude of change does not differentiate patients with sepsis from those without sepsis. Increased intestinal permeability before surgery is of no value in predicating sepsis. The present study aimed to observe the changes of intestinal mucosal immunologic barrier in rat models of sepsis induced by cecal ligation and puncture. METHODS: Sixty Sprague-Dawley rats were randomly divided into a sepsis group (n=45) and a control group (n=15). The rats in the sepsis group were subjected to cecal ligation and puncture (CLP), whereas the rats in the control group underwent a sham operation. The ileac mucosa and segments were harvested 3, 6 and 12 hours after CLP, and blood samples were collected. Pathological changes, protein levels of defensin-5 (RD-5) and trefoil factor-3 (TFF3) mRNA, and lymphocytes apoptosis in the intestinal mucosa were determined. In an additional experiment, the gut-origin bacterial DNA in blood was detected. RESULTS: The intestinal mucosa showed marked injury with loss of ileal villi, desquamation of epithelium, detachment of lamina propria, hemorrhage and ulceration in the sepsis group. The expression of TFF3 mRNA and level of RD-5 protein were decreased and the apoptosis of mucosal lymphocyte increased (P<0.05) in the sepsis group compared with the control group. Significant differences were observed in RD-5 and TFF3 mRNA 3 hours after CLP and they were progressively increased 6 and 12 hours after CLP in the sepsis group compared with the control group (P<0.05, RD-5 F=11.76, TFF3 F=16.86 and apoptosis F=122.52). In addition, the gut-origin bacterial DNA detected in plasma was positive in the sepsis group. CONCLUSION: The immunological function of the intestinal mucosa was impaired in septic rats and further deteriorated in the course of sepsis.