Discovery of a novel inhibitor of nitric oxide production with potential therapeutic effect on acute inflammation.

Inflammation as a host's excessive immune response to stimulation, is involved in the development of numerous diseases. To discover novel anti-inflammatory agents and based on our previous synthetic work on marine natural product Chrysamide B, it and a series of derivatives were synthesized and evaluated for their anti-inflammatory activity on inhibition of LPS-induced NO production. Then the preliminary structure-activity relationships were conducted. Among them, Chrysamide B is the most potent anti-inflammatory agent with low cytotoxicity and strong inhibition on the production of NO (IC50 = 0.010 µM) and the activity of iNOS (IC50 = 0.082 µM) in LPS-stimulated RAW 264.7 cells. Primary studies suggested that the mechanism of action may be that it interfered the formation of active dimeric iNOS but not affected transcription and translation. Furthermore, its good performance of anti-inflammatory effect on LPS-induced multiple inflammatory cytokines production, carrageenan-induced paw edema, and endotoxin-induced septic mice, was observed. We believe that these findings would provide an idea for the further modification and research of these analogs in the future.

A novel DNA methylation-based model that effectively predicts prognosis in hepatocellular carcinoma.

PURPOSE: To build a novel predictive model for hepatocellular carcinoma (HCC) patients based on DNA methylation data. METHODS: Four independent DNA methylation datasets for HCC were used to screen for common differentially methylated genes (CDMGs). Gene Ontology (GO) enrichment, and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis were used to explore the biological roles of CDMGs in HCC. Univariate Cox analysis and least absolute shrinkage and selection operator (LASSO) Cox analysis were performed to identify survival-related CDMGs (SR-CDMGs) and to build a predictive model. The importance of this model was assessed using Cox regression analysis, propensity score-matched (PSM) analysis and stratification analysis. A validation group from the Cancer Genome Atlas (TCGA) was constructed to further validate the model. RESULTS: Four SR-CDMGs were identified and used to build the predictive model. The risk score of this model was calculated as follows: risk score = (0.01489826 × methylation level of WDR69) + (0.15868618 × methylation level of HOXB4) + (0.16674959 × methylation level of CDKL2) + (0.16689301 × methylation level of HOXA10). Kaplan-Meier analysis demonstrated that patients in the low-risk group had a significantly longer overall survival (OS; log-rank P-value =0.00071). The Cox model multivariate analysis and PSM analysis identified the risk score as an independent prognostic factor (P<0.05). Stratified analysis results further confirmed this model performed well. By analyzing the validation group, the results of receiver operating characteristic (ROC) curve analysis and survival analysis further validated this model. CONCLUSION: Our DNA methylation-based prognosis predictive model is effective and reliable in predicting prognosis for patients with HCC.

Ribosome assembly factor URB1 contributes to colorectal cancer proliferation through transcriptional activation of ATF4.

Ribosome assembly factor URB1 is essential for ribosome biogenesis. However, its latent role in cancer remains unclear. Analysis of The Cancer Genome Atlas database and clinical tissue microarray staining showed that URB1 expression was upregulated in colorectal cancer (CRC) and prominently related to clinicopathological characteristics. Silencing of URB1 hampered human CRC cell proliferation and growth in vitro and in vivo. Microarray screening, ingenuity pathway analysis, and JASPAR assessment indicated that activating transcription factor 4 (ATF4) and X-box binding protein 1 (XBP1) are potential downstream targets of URB1 and could transcriptionally interact through direct binding. Silencing of URB1 significantly decreased ATF4 and cyclin A2 (CCNA2) expression in vivo and in vitro. Restoration of ATF4 effectively reversed the malignant proliferation phenotype of URB1-silenced CRC cells. Dual-luciferase reporter and ChIP assays indicated that XBP1 transcriptionally activated ATF4 by binding with its promoter region. X-box binding protein 1 colocalized with ATF4 in the nuclei of RKO cells, and ATF4 mRNA expression was positively regulated by XBP1. This study shows that URB1 contributes to oncogenesis and CRC growth through XBP1-mediated transcriptional activation of ATF4. Therefore, URB1 could be a potential therapeutic target for CRC.

Correlation between the expressions of circular RNAs in peripheral venous blood and clinicopathological features in hepatocellular carcinoma.

BACKGROUND: Recent studies have reported that circular RNAs (circRNAs) are involved in the development of hepatocellular carcinoma (HCC). This study evaluated the expression of preoperative peripheral venous blood circRNAs in HCC patients and their predictive ability for microvascular invasion (MVI). METHODS: Seven circRNAs (circMTO1, circ-10720, circZKSCAN1, cSMARCA5, circHIPK3, circSETD3 and ciRS-7) were screened from the literature as circRNAs with reported biological functions in HCC. The expression levels of seven circRNAs in preoperative blood samples and HCC tissues were detected by quantitative reverse transcription polymerase chain reaction. The correlations between the circRNA expressions in blood and the clinicopathological factors of HCC patients were analyzed. The risk factors of MVI were analyzed by univariate and multivariate logistic regression. The functional role of circSETD3 in cell migration and invasion was evaluated by wound healing and Transwell assays in vitro. RESULTS: The expressions of all seven circRNAs were measured in peripheral venous blood samples. The venous expression levels of circHIPK3 and circMTO1 were significantly associated with gender, while circ-10720 and circMTO1 levels were significantly correlated with gross vascular invasion. Furthermore, circMTO1 and cSMARCA5 levels were significantly associated with alpha-fetoprotein level and ciRS-7 was significantly associated with satellite nodules. Importantly, low venous circSETD3 expression was significantly associated with prothrombin induced by vitamin K absence or antagonist-II (PIVKA-II) level, MVI, gross vascular invasion, and liver capsule. Furthermore, venous circSETD3 expression had predictive ability for MVI. Knockdown of circSETD3 promoted cell invasion and metastasis in vitro. CONCLUSIONS: CircRNAs were stably present in peripheral venous blood and associated with multiple clinicopathological characteristics of HCC patients. Venous circSETD3 was an independent risk factor of MVI and shows ability to predict MVI in HCC patients before surgery.

RAPTOR promotes colorectal cancer proliferation by inducing mTORC1 and upregulating ribosome assembly factor URB1.

Mammalian target of rapamycin complex 1 (mTORC1) is evolutionally conserved and frequently activated in various tumors, including colorectal cancer (CRC). It has been reported that the ribosome assembly factor Urb1 acts downstream of mTORC1/raptor signaling and contributes to digestive organ development in zebrafish. Previously, we highlighted that URB1 was overexpressed in CRC. Here, we assessed the mTORC1/regulatory associated protein with mTOR (RAPTOR)-URB1 axis in CRC tumorigenesis. We found that RAPTOR was overexpressed in CRC tissues and cell lines, was a favorable predictor in patients with CRC, and positively correlated with URB1. Silencing of RAPTOR suppressed CRC cell proliferation and migration and induced cell cycle arrest and apoptosis in vitro and inhibited xenograft growth in vivo. Moreover, ectopic overexpression of RAPTOR exerted an inverse biological phenotype. Knockdown of RAPTOR quenched mTORC1 activity and reduced the expression of URB1 and cyclinA2 (CCNA2). In contrast, overexpression of RAPTOR activated mTORC1 and upregulated URB1 and CCNA2. Furthermore, URB1 and CCNA2 expression were also impeded by rapamycin, which is a specific inhibitor of mTORC1. Thus, RAPTOR promoted CRC proliferation, migration, and cell cycle progression by inducing mTORC1 signaling and transcriptional activation of both URB1 and CCNA2. Taken together, we concluded that RAPTOR has the potential to serve as a novel biomarker and therapeutic target for CRC.

Efficacy and safety of radiofrequency ablation versus minimally invasive liver surgery for small hepatocellular carcinoma: a systematic review and meta-analysis.

BACKGROUND: The aim of this study was to compare radiofrequency ablation (RFA) with minimally invasive liver surgery (MIS) in the treatment of small hepatocellular carcinoma (SHCC) and to assess short-term and long-term clinical outcomes. METHODS: PubMed, Embase, Cochrane Library, Web of science, and CBM were systematically searched for articles from inception to July 2018, comparing RFA and MIS in SHCC treatment. We evaluated overall survival (OS), disease-free survival (DFS), local recurrence, and complication rates, as well as hospitalization duration and operation times. RESULTS: Six retrospective studies were analyzed, including a total of 597 patients, 313 treated with RFA and 284 treated with MIS. OS rates were significantly higher in patients treated with MIS at 3 years, when compared to RFA (OR 0.55; 95% CI 0.36 to 0.84). The 3-year DFS MIS rates were also superior to RFA (OR 0.63; 95% CI 0.41 to 0.98). In contrast, when compared to MIS, RFA demonstrated a significantly higher rate of local intrahepatic recurrences, (OR 2.24; 95% CI 1.47 to 3.42), and a lower incidence of postoperative complications (OR 0.34; 95% CI 0.22 to 0.53), as well as shorter operation times (OR - 145.31, 95% CI - 200.24 to - 90.38) and hospitalization duration (OR - 4.02,95% CI - 4.94 to - 3.10). CONCLUSIONS: We found that MIS led to higher OS, DFS, and lower local recurrences in SHCC patients. Meanwhile, RFA treatments led to significantly lower complication rates, shorter operation times, and hospitalization duration. Considering long-term outcomes, MIS was found to be superior to RFA. However, RFA may be an alternative treatment for patients presenting a single SHCC nodule (≤ 3 cm), given its minimally invasive nature and its comparable long-term efficacy with MIS. Nevertheless, our findings should be explained with caution due to the low level of evidence obtained.

Safety and effectiveness of day-surgery laparoscopic cholecystectomy is still uncertain: meta-analysis of eight randomized controlled trials based on GRADE approach.

BACKGROUND: Currently, there is no consensus on whether laparoscopic cholecystectomy (LC) performed as day-surgery is safe and effective and can be considered as the standard for the management of symptomatic gallbladder disease. We conducted a meta-analysis of randomized controlled trials (RCTs) to evaluate the safety and effectiveness of this intervention based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. METHODS: We conducted a systematic search of several databases from their inception to November 10, 2016 for entries on the mortality, morbidity after discharge, readmission, postoperative morbidity, and patient satisfaction at 1 week of day-surgery LC. Pooled risk ratio (RR) with 95% confidence intervals (CI) was calculated using the fixed-effects model. Rare outcomes were presented as the Peto odds ratio (Peto OR). Meta-analysis was performed by using the RevMan 5.1 software, and the level of evidence was assessed by using the GRADE guideline and GRADEpro GDT software. RESULTS: Eight RCTs totaling 624 participants were included. The result showed no intergroup difference in short-term mortality. Compared to overnight-stay surgery, day-surgery did not show any clear evidence of reduced morbidity after discharge (Peto OR 0.89; 95% CI 0.39-2.02), lower readmission rate (Peto OR 0.68; 95% CI 0.23-2.05), or higher postoperative morbidity rates (RR 1.28; 95% CI 0.81-2.02). However, the results suggested that day-surgery may improve patient satisfaction at 1 week (RR 1.17; 95% CI 1.03-1.33). Evaluation by the GRADE approach revealed that the quality of evidence for each outcome was of low to very low quality due to the risk of bias, imprecision, and inconsistency. CONCLUSION: Our meta-analysis shows that the safety and effectiveness of day-surgery LC is still uncertain. Additional well-designed and adequately powered RCTs are required before the procedure can be recommended as the standard for clinical practice.

Topical phenytoin for treating pressure ulcers.

BACKGROUND: Pressure ulcers are common in clinical practice and pose a significant health problem worldwide. Apart from causing suffering to patients, they also result in longer hospital stays and increase the cost of health care. A variety of methods are used for treating pressure ulcers, including pressure relief, patient repositioning, biophysical strategies, nutritional supplementation, debridement, topical negative pressure, and local treatments including dressings, ointments and creams such as bacitracin, silver sulphadiazine, neomycin, and phenytoin. Phenytoin is a drug more commonly used in the treatment of epilepsy, but may play an important role in accelerating ulcer healing. OBJECTIVES: To assess the effects of topical phenytoin on the rate of healing of pressure ulcers of any grade, in any care setting. SEARCH METHODS: In September 2016, we searched the following electronic databases to identify relevant randomized clinical trials: the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL; the Cochrane Library); Ovid MEDLINE; Ovid Embase; and EBSCO CINAHL Plus. We handsearched conference proceedings from the European Pressure Ulcer Advisory Panel, European Wound Management Association and the Tissue Viability Society for all available years. We searched the references of the retrieved trials to identify further relevant trials. We also searched clinical trials registries to identify ongoing and unpublished studies. There were no restrictions with respect to language, date of publication or study setting. SELECTION CRITERIA: We included all randomized controlled trials (RCTs) addressing the effects (both benefits and harms) of topical phenytoin on the healing of pressure ulcers of any grade compared with placebo or alternative treatments or no therapy, irrespective of blinding, language, and publication status. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, extracted information on participants, interventions, methods and results and assessed risk of bias using Cochrane methodological procedures. For dichotomous variables, we calculated the risk ratio (RR) with 95% confidence interval (CI). For continuous variables, we calculated the mean difference with 95% CI. We rated the quality of the evidence by using Grading of Recommendations, Assessment, Development and Evaluation approach (GRADE). MAIN RESULTS: Three small RCTs met our inclusion criteria and included a total of 148 participants. These compared three treatments with topical phenytoin: hydrocolloid dressings, triple antibiotic ointment and simple dressings. In the three RCTs, 79% of participants had grade II ulcers, and 21% of participants had grade I ulcers; no participants had grade III or IV ulcers. Two RCTs had a high risk of bias overall and the other RCT was at unclear risk of bias due to poor reporting. Two RCTs had three intervention arms and the other had two intervention arms.Two studies compared topical phenytoin with hydrocolloid dressing (84 participants analysed). The available data suggest that hydrocolloid dressings may improve ulcer healing compared to topical phenytoin (39.3% ulcers healed for phenytoin versus 71.4% ulcers healed for hydrocolloid dressings (RR 0.55, 95% CI 0.33 to 0.92; 56 participants, 1 study; low quality evidence). We downgraded the evidence twice: once due to serious limitations (high risk of bias) and once due to the small sample size and small number of events. Two studies compared topical phenytoin with simple dressings (81 participants analysed). From the available data, we are uncertain whether topical phenytoin improves ulcer healing compared to simple dressings (39.3% ulcers healed for phenytoin versus 29.6% ulcers healed for the simple dressing (RR 1.33, 95% CI 0.63 to 2.78; 55 participants, 1 study; very low quality evidence). This evidence was downgraded once due to serious limitations (high risk of bias) and twice due to the low number of outcome events and resulting wide CI which included the possibility of both increased healing and reduced healing. We therefore considered it to be insufficient to determine the effect of topical phenytoin on ulcer healing. One study compared topical phenytoin with triple antibiotic ointment, however, none of the outcomes of interest to this review were reported. No adverse drug reactions or interactions were detected in any of the three RCTs. Minimal pain was reported in all groups in one trial that compared topical phenytoin with hydrocolloid dressings and triple antibiotic ointment. AUTHORS' CONCLUSIONS: This review has considered the available evidence and the result shows that it is uncertain whether topical phenytoin improves ulcer healing for patients with grade I and II pressure ulcers. No adverse events were reported from three small trials and minimal pain was reported in one trial. Therefore, further rigorous, adequately powered RCTs examining the effects of topical phenytoin for treating pressure ulcers, and to report on adverse events, quality of life and costs are necessary.

High dose rate versus low dose rate intracavity brachytherapy for locally advanced uterine cervix cancer.

BACKGROUND: This is an updated version of the original Cochrane review published in 2010 (Issue 7).Carcinoma of the uterine cervix is the second most common cancer and the third leading cause of cancer death among women. Radiotherapy has been used successfully to treat cervical cancer for nearly a century. The combination of external beam radiotherapy (EBRT) and intracavity brachytherapy (ICBT) has become a standard treatment for cervical cancer. Whether high dose rate (HDR) or low dose rate (LDR) brachytherapy improves outcomes in terms of local control rates, survival and complications for women with cervical cancer remains controversial. OBJECTIVES: To assess the efficacy and safety of HDR versus LDR ICBT in combination with EBRT for women with uterine cervical cancer. SEARCH METHODS: We searched the Cochrane Gynaecological Cancer Group Specialised Register and the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 1), MEDLINE (1966 to March 2014), EMBASE (1974 to March 2014), and the Chinese Biomedical Literature Database (CBM) (1978 to March 2014) for relevant original, published trials. SELECTION CRITERIA: Randomised controlled trials (RCTs) and quasi-RCTs that compared HDR with LDR ICBT, combined with EBRT, for women with locally advanced uterine cervical cancer. DATA COLLECTION AND ANALYSIS: Two authors independently extracted the data using standardised forms. Primary outcome measures included overall survival (OS), relapse-free survival (RFS) and pelvic control rate, while secondary outcomes included rates of recurrence and complications. MAIN RESULTS: Four studies involving 1265 women met the inclusion criteria. In our meta-analysis to compare HDR and LDR ICBT, the pooled risk ratios (RRs) were 0.95 (95% confidence interval (CI) 0.79 to 1.15), 0.93 (95% CI 0.84 to 1.04) and 0.79 (95% CI 0.52 to 1.20) for 3-, 5- and 10-year overall survival rates respectively; and 0.95 (95% CI 0.84 to 1.07) and 1.02 (0.88 to 1.19) for 5- and 10-year disease-specific survival (DSS) rates respectively. The RR for RFS was 1.04 (95% CI 0.71 to 1.52) and 0.96 (95% CI 0.81 to 1.14) at 3- and 5- years. For local control rates the RR was 0.95 (95% CI 0.86 to 1.05) and 0.95 (95% CI 0.87 to 1.05) at 3- and 5- years; with a RR of 1.09 (95% CI 0.83 to 1.43) for locoregional recurrence, 0.79 (95% CI 0.40 to 1.53) for local and distant recurrence, 2.23 (95% CI 0.78 to 6.34) for para-aortic lymph node metastasis, and 0.99 (95% CI 0.72 to 1.35) for distance metastasis. For bladder, rectosigmoid and small bowel complications, the RR was 1.33 (95% CI 0.53 to 3.34), 1.00 (95% CI 0.52 to 1.91) and 3.37 (95% CI 1.06 to 10.72) respectively. These results indicated that there were no significant differences except for increased small bowel complications with HDRs (P = 0.04). AUTHORS' CONCLUSIONS: Since the last version of this review, no new studies were identified for inclusion in this review to provide additional information. This review showed no significant differences between HDR and LDR ICBT when considering OS, DSS, RFS, local control rate, recurrence, metastasis and treatment related complications for women with cervical carcinoma. Due to some potential advantages of HDR ICBT (rigid immobilization, outpatient treatment, patient convenience, accuracy of source and applicator positioning, individualized treatment) we recommend the use of HDR ICBT for all clinical stages of cervix cancer. The overall risk of bias was high for the included studies as many of the items were either of high or unclear risk. The GRADE assessment of the quality of the evidence was low to moderate.

High dose rate versus low dose rate intracavity brachytherapy for locally advanced uterine cervix cancer.

BACKGROUND: Carcinoma of the uterine cervix is the second most common cancer and the third leading cause of cancer death among women. Radiotherapy has been used successfully to treat cervical cancer for nearly a century. The combination of external beam radiotherapy (EBRT) and intracavitary brachytherapy (ICBT) has become a standard treatment modality for cervical cancer. Depending on the difference in dose rate on 'Point A' (located 2 cm above the cervical os and 2 cm lateral to the central axis of the uterus), the ICBT is divided into three modalities: low dose rate (LDR), high dose rate (HDR) and medium dose rate (MDR). Despite the practical advantages of HDR, it is necessary to investigate further the efficacy and safety of HDR brachytherapy compared to LDR brachytherapy. Questions arise as to whether HDR or LDR brachytherapy improves results for patients with cervical cancer in terms of local control rates, survival and complications related to treatment. OBJECTIVES: To assess the efficacy and safety of HDR- versus LDR-ICBT for patients with uterine cervical cancer. SEARCH STRATEGY: We searched the Cochrane Gynaecological Cancer Group Specialised Register and the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2009, Issue 4), MEDLINE (1966 to November 2009), EMBASE (1974 to November 2009), Chinese Biomedical Literature Database (CBM) (1978 to November 2009) for relevant original, published trials. SELECTION CRITERIA: Randomised controlled trials (RCTs) and quasi-RCTs that compared HDR- with LDR-ICBT, combined with EBRT, for patients with locally advanced uterine cervical cancer. DATA COLLECTION AND ANALYSIS: Two authors independently extracted the data using standardised forms. Primary outcome measures included overall survival (OS), relapse-free survival (RFS) and pelvic control rate, while secondary outcomes included rates of recurrence and complications. MAIN RESULTS: Four studies involving 1265 patients met the inclusion criteria. In our meta-analysis to compare HDR and LDR, the pooled RRs were 0.95 (95% CI 0.79 to 1.15), 0.93 (95% CI 0.84 to 1.04) and 0.79 (95% CI 0.52 to 1.20) for 3-, 5- and 10-year overall survival rates; and 0.95 (95% CI 0.84 to 1.07) and 1.02 (0.88 to 1.19) for 5- and 10-year disease-specific survival (DSS) rates. The RR for RFS was 1.04 (95% CI 0.71 to 1.52) and 0.96 (95% CI 0.81 to 1.14) at three and five years. For local control rates the RR was 0.95 (95% CI 0.86 to 1.05) and 0.95 (95% CI 0.87 to 1.05) at three and five years; with a RR of 1.09 (95% CI 0.83 to 1.43) for locoregional recurrence, 0.79 (95% CI 0.40 to 1.53) for local and distance recurrence, 2.23 (95% CI 0.78 to 6.34) for para-aortic lymph node metastasis and 0.99 (95% CI 0.72 to 1.35) for distance metastasis. For bladder, rectosigmoid and small bowel complications, the RR was 1.33 (95% CI 0.53 to 3.34), 1.00 (95% CI 0.52 to 1.91) and 3.37 (95% CI 1.06 to 10.72), respectively. These results indicate that there were no significant differences except for increased small bowel complications with HDR (P = 0.04). AUTHORS' CONCLUSIONS: This review showed no significant differences between HDR- and LDR-ICBT when considering OS, DSS, RFS, local control rate, recurrence, metastasis and treatment related complications for women with cervical carcinoma. Due to some potential advantages of HDR-ICBT (rigid immobilization, outpatient treatment, patient convenience, accuracy of source and applicator positioning, individualized treatment) we recommend the use of HDR-ICBT for all clinical stages of cervix cancer.

Octreotide for advanced hepatocellular carcinoma: a meta-analysis of randomized controlled trials.

PURPOSE: To evaluate the effectiveness of octreotide in advanced hepatocellular carcinoma participants on the basis of randomized controlled trials. METHODS: We searched the Cochrane Center Register of Controlled Trials in The Cochrane Library, PubMed, EMBASE, Chinese Biomedical Literature Database, China Journal Full-text Database, Chinese Scientific Journals Database up to June 2008 in any language. Randomized controlled trials of octreotide for advanced hepatocellular carcinoma were selected and evaluated by two investigators. Any disagreement was solved by discussion. Analyses were performed using Review Manager 4.2. RESULTS: Six randomized controlled trials totaling 352 participants were included. The median survival time was reported in four randomized controlled trials. The results between the octreotide group and the control group (the placebo or best supportive care group) were as follows: 13.0 versus 4.0 months, 1.93 versus 1.97 months, 4.7 versus 5.3 months, and 7.0 versus 2.5 months. Three randomized controlled trials reported 6-month survival rates and 12-month survival rates and meta-analysis results in these two outcomes [(RR 1.35, 95% CI 0.92-1.97); (RR 1.35, 95% CI 0.66-11.16) respectively] were not found to be statistically significant by random-effects model. When we analyzed 6-month survival rates by fixed-effect model (RR 1.30, 95% CI 1.02-1.66), meta-analysis result reached statistical significance. CONCLUSIONS: As for the limitations of the included trials, the result may not demonstrate a significant superiority of octreotide administration in participants with advanced hepatocellular carcinoma from the available evidence.

Omentoplasty in the prevention of anastomotic leakage after colorectal resection: a meta-analysis.

PURPOSE: Whether omentoplasty after colorectal anastomosis can reduce anastomotic leakage is controversial. Our aim was to do a meta-analysis of randomized controlled trials to compare anastomotic leakage rates between an omentoplasty group and a no omentoplasty group after colorectal anastomosis. MATERIALS AND METHODS: We searched the Cochrane Center Register of Controlled Trials, PubMed, EMBASE, and Chinese Biomedical Literature Database up to June 2008 in any language. Reference lists from all selected articles were also examined. Randomized controlled trials of omentoplasty in the prevention of anastomotic leakage after colorectal resection were selected and evaluated by two investigators. Analyses were performed using Review Manager 4.2. RESULTS: Three randomized controlled trials totaling 943 participants were included. Meta-analysis results showed that no statistically significant difference was found between the omentoplasty group and the no omentoplasty group in radiological anastomotic leakage (RR 0.76, 95% CI 0.41 to 1.40), death (RR 1.01, 95% CI 0.55 to 1.86), and repeat operation (RR 0.60, 95% CI 0.35 to 1.05), except for clinical anastomotic leakage (RR 0.36, 95% CI 0.16 to 0.78). CONCLUSION: Based on available data from a small number of trials, there is not enough evidence to say whether or not omentoplasty should be used to reduce anastomotic leakage after colorectal resection. The decision as to whether we should continue to use this technique might remain a matter of surgical judgment. Therefore, the results still need to be confirmed by future multicenter, well-designed trials.