Kailin Cai

The Safety and Efficiency of Surgery with Colonic Stents in Left-Sided Malignant Colonic Obstruction: A Meta-Analysis

Objective. This meta-analysis is aimed at assessing the safety and efficiency of colonic self-expanding metallic stents (SEMS) used as a bridge to surgery in the management of left-sided malignant colonic obstruction (LMCO). Methods. A systematic search was conducted in PubMed, Web of Knowledge, OVID, Google Scholar, CNKI, and WANGFANG for relevant randomized trials comparing colonic stenting used as a bridge in semielective surgery versus emergency surgery from January 2001 to September 2013. Result. Five published studies were included in this systematic review, including 273 patients (140 male/133 female). 136 patients received semielective surgery after SEMS installation while 137 patients underwent emergency surgery without SEMS. SEMS intervention resulted in significantly lower overall colostomy rate (41.9% versus 56.2%, P = 0.02), surgical site infection rate (10.2% versus 19.7%, P = 0.03), and overall complication rate (29.2% versus 60.5%, P = 0.05). There was no statistic difference for the rate of primary anastomosis, anastomotic leak and operation-related mortality between two groups. Conclusions. semielective surgery with SEMS as a bridge for proper patients of LMCO can lower the overall rate for colostomy, surgical site infection, and complications.

Role of IL-17 and TGF-β in peritoneal adhesion formation after surgical trauma

Peritoneal adhesions are fibrous tissues formed after surgery. Both cytokines and transforming growth factors (TGFs) are involved in this process. The objective of this study was to investigate the cross talk between these entities. Peritoneal drainage fluid after surgery from patients and rodent models was examined by enzyme‐linked immunosorbent assay and fluorescence‐activated cell sorter. Data showed that the concentrations of interferon (IFN)‐γ and interleukin (IL)‐17 reached their peaks 6–12 hours after surgery, whereas TGF‐β1 concentrations showed two postoperative peak time points at 2 and 72–96 hours. By neutralizing IFN‐γ, IL‐17 6–12 hours, and TGF‐β1 72–96 hours after surgery, the degree of adhesion reduced significantly. However, neutralizing TGF‐β1 2 hours after surgery did not affect adhesion formation. Furthermore, in vitro studies showed that compared with the fibroblasts that were directly stimulated with TGF‐β1, the prestimulation of IL‐17 promoted plasminogen activator inhibitor‐1 production while inhibiting tissue‐type plasminogen activator production. Moreover, additional stimulation with IFN‐γ enhanced this effect. Together, these data indicate that IL‐17 may promote adhesion formation by increasing the reaction of fibroblasts against TGF‐β1. Blocking IL‐17 might have a therapeutic potential in preventing adhesion formation after surgery.

Tumor-infiltrating immune cells and prognosis in gastric cancer: a systematic review and meta-analysis

Tumor-infiltrating immune cells are a pivotal component of the tumor microenvironment (TME), but their indicative role remains poorly defined. A meta-analysis was performed to reveal the prognostic efficiency of tumor-infiltrating immune cells in gastric cancer (GC). By searching PubMed and Embase, we identified a total of 35 eligible articles that involved 4888 patients. Random or fixed effect models were employed to extract pooled hazard ratios (HRs) with 95% confidence intervals (CIs). Our results indicated that high CD3+ lymphocyte infiltration in all the locations (AG), the tumor nest (TN), and the tumor stroma (TS) predicted better overall survival (OS) (HR=0.71, 95% CI=0.57-0.90; HR=0.58, 95% CI=0.42-0.80; and HR=0.50, 95% CI=0.37-0.68, respectively). CD8+ T cell infiltration in AG and FoxP3+ regulatory T cells (Tregs) in the tumor invasive margin (TM) were also associated with improved OS (HR=0.90, 95% CI=0.83-0.97; HR=0.65, 95% CI=0.48-0.87, respectively). However, contrasting results were found in the macrophage subset, with M2 in AG (HR=1.45, 95% CI=1.13-1.86) and the TN (HR=1.67, 95% CI=1.12-2.48) associated with worse OS. In summary, the combination of the densities and locations of tumor-infiltrating immune cells can be useful for predicting survival for GC patients, but additional research is needed to reinforce the reliability of this study’s conclusions.Tumor-infiltrating immune cells are a pivotal component of the tumor microenvironment (TME), but their indicative role remains poorly defined. A meta-analysis was performed to reveal the prognostic efficiency of tumor-infiltrating immune cells in gastric cancer (GC). By searching PubMed and Embase, we identified a total of 35 eligible articles that involved 4888 patients. Random or fixed effect models were employed to extract pooled hazard ratios (HRs) with 95% confidence intervals (CIs). Our results indicated that high CD3+ lymphocyte infiltration in all the locations (AG), the tumor nest (TN), and the tumor stroma (TS) predicted better overall survival (OS) (HR=0.71, 95% CI=0.57-0.90; HR=0.58, 95% CI=0.42-0.80; and HR=0.50, 95% CI=0.37-0.68, respectively). CD8+ T cell infiltration in AG and FoxP3+ regulatory T cells (Tregs) in the tumor invasive margin (TM) were also associated with improved OS (HR=0.90, 95% CI=0.83-0.97; HR=0.65, 95% CI=0.48-0.87, respectively). However, contrasting results were found in the macrophage subset, with M2 in AG (HR=1.45, 95% CI=1.13-1.86) and the TN (HR=1.67, 95% CI=1.12-2.48) associated with worse OS. In summary, the combination of the densities and locations of tumor-infiltrating immune cells can be useful for predicting survival for GC patients, but additional research is needed to reinforce the reliability of this studys conclusions.

Clinicopathologic Features of Gastric Schwannoma: 8-Year Experience at a Single Institution in China.

AbstractTo explore the clinicopathologic characteristics, diagnosis, treatment, and prognosis of gastric schwannoma in the imatinib era.The clinicopathologic characteristics and postoperative outcomes of patients diagnosed with gastric schwannoma at our institution between January 2007 and February 2015 were retrospectively collected and analyzed.The main patient complaint was epigastric pain or discomfort. Tumor sizes ranged from 15 to 80 mm (mean, 57.1 mm). In 17 patients, the tumors were located in the body of the stomach. A total of 20 patients were preoperatively misdiagnosed with a gastrointestinal stromal tumor. The rate of correct preoperative diagnosis was only 3.3%. All patients underwent surgical resection and showed strong S-100 protein positivity. Laparoscopic surgery for gastric schwannoma was associated with less blood loss and a shorter postoperative hospital stay than open surgery (P < 0.01). Total 28 patients were disease free without recurrence or metastasis at a median follow-up time of 50 months.Gastric schwannoma is often preoperatively misdiagnosed as gastric gastrointestinal stromal tumor. Laparoscopic resection of gastric schwannoma is considered safe and effective, and it may be the preferred surgery for most small- and moderate-sized tumors. The long-term outcome is excellent, as this type of neoplasm is uniformly benign.

Influence of Bariatric Surgery on the Expression of Nesfatin-1 in Rats with Type 2 Diabetes Mellitus

OBJECTIVE Bariatric surgery has been reported to be very effective in the remission of type 2 diabetes mellitus (T2DM). However, the mechanism is still under debate. Nesfatin-1, a recently discovered anorexigenic neuropeptide, was reported to be very important in glucose metabolism and regulating food intake. In this study, the effects of bariatric surgery on the expression and regulation of nesfatin-1 were discussed. METHODS T2DM was induced in SD rats by a diet high in sugar and fat plus a low dose of streptozotocin (STZ) (25 mg/kg) injection. Bariatric surgeries, including Roux-En-Y Gastric Bypass (RYGB) and sleeve gastrectomy (SG), were performed on these rats. Two months after the surgery, the plasma nesfatin-1 level and the expression of nesfatin-1 in different organs of the rats were tested. Next, in vivo administration of nesfatin-1 after surgery was performed to investigate the role of nesfatin-1 in bariatric surgery. RESULTS Both RYGB and SG could reduce the weight of the rats. However, only RYGB had significant effects on the blood glucose level. Neither surgeries seemed to affect the blood concentration of insulin. However, RYGB significantly improved insulin sensitivity. Expression of nesfatin-1 in the plasma and relative organs decreased in T2DM rats and rose again after RYGB; however, this pattern did not occur in SG. Injection of nesfatin-1 after SG significantly improved insulin resistance and reduced blood glucose levels. CONCLUSIONS Nesfatin-1 may improve insulin sensitivity in T2DM rats and thus plays a very important role in the remission of T2DM after RYGB. This neuropeptide could be a new target for directing future improvements in the bariatric surgical process.

The Diagnostic Performance of Stool DNA Testing for Colorectal Cancer: A Systematic Review and Meta-Analysis.

Abstract This meta-analysis was designed to evaluate the diagnostic performance of stool DNA testing for colorectal cancer (CRC) and compare the performance between single-gene and multiple-gene tests. MEDLINE, Cochrane, EMBASE databases were searched using keywords colorectal cancers, stool/fecal, sensitivity, specificity, DNA, and screening. Sensitivity analysis, quality assessments, and performance bias were performed for the included studies. Fifty-three studies were included in the analysis with a total sample size of 7524 patients. The studies were heterogeneous with regard to the genes being analyzed for fecal genetic biomarkers of CRC, as well as the laboratory methods being used for each assay. The sensitivity of the different assays ranged from 2% to 100% and the specificity ranged from 81% to 100%. The meta-analysis found that the pooled sensitivities for single- and multigene assays were 48.0% and 77.8%, respectively, while the pooled specificities were 97.0% and 92.7%. Receiver operator curves and diagnostic odds ratios showed no significant difference between both tests with regard to sensitivity or specificity. This meta-analysis revealed that using assays that evaluated multiple genes compared with single-gene assays did not increase the sensitivity or specificity of stool DNA testing in detecting CRC.

Anatomical basis and clinical research of pelvic autonomic nerve preservation with laparoscopic radical resection for rectal cancer.

SummaryThe clinical effect of laparoscopic rectal cancer curative excision with pelvic autonomic nerve preservation (PANP) was investigated. This study evaluated the frequency of urinary and sexual dysfunction of 149 male patients with middle and low rectal cancer who underwent laparoscopic or open total mesorectal excision with pelvic autonomic nerve preservation (PANP) from March 2011 to March 2013. Eighty-four patients were subjected to laparoscopic surgery, and 65 to open surgery respectively. The patients were followed up for 12 months, interviewed, and administered a standardized questionnaire about postoperative functional outcomes and quality of life. In the laparoscopic group, 13 patients (18.37%) presented transitory postoperative urinary dysfunction, and were medically treated. So did 12 patients (21.82%) in open group. Sexual desire was maintained by 52.86%, un-ability to engage in intercourse by 47.15%, and un-ability to achieve orgasm and ejaculation by 34.29% of the patients in the laparoscopic group. Sexual desire was maintained by 56.36%, un-ability to engage in intercourse by 43.63%, and un-ability to achieve orgasm and ejaculation by 33.73% of the patients in the open group. No significant differences in urinary and sexual dysfunction between the laparoscopic and open rectal resection groups were observed (P>0.05). It was concluded that laparoscopic rectal cancer radical excision with PANP did not aggravate or improve sexual and urinary dysfunction.The clinical effect of laparoscopic rectal cancer curative excision with pelvic autonomic nerve preservation (PANP) was investigated. This study evaluated the frequency of urinary and sexual dysfunction of 149 male patients with middle and low rectal cancer who underwent laparoscopic or open total mesorectal excision with pelvic autonomic nerve preservation (PANP) from March 2011 to March 2013. Eighty-four patients were subjected to laparoscopic surgery, and 65 to open surgery respectively. The patients were followed up for 12 months, interviewed, and administered a standardized questionnaire about postoperative functional outcomes and quality of life. In the laparoscopic group, 13 patients (18.37%) presented transitory postoperative urinary dysfunction, and were medically treated. So did 12 patients (21.82%) in open group. Sexual desire was maintained by 52.86%, un-ability to engage in intercourse by 47.15%, and un-ability to achieve orgasm and ejaculation by 34.29% of the patients in the laparoscopic group. Sexual desire was maintained by 56.36%, un-ability to engage in intercourse by 43.63%, and un-ability to achieve orgasm and ejaculation by 33.73% of the patients in the open group. No significant differences in urinary and sexual dysfunction between the laparoscopic and open rectal resection groups were observed (P>0.05). It was concluded that laparoscopic rectal cancer radical excision with PANP did not aggravate or improve sexual and urinary dysfunction.

A Linear Dose-Response Relationship between Fasting Plasma Glucose and Colorectal Cancer Risk: Systematic Review and Meta-analysis.

For many years, the question of whether hyperglycaemia, a manifestation of prediabetes, diabetes mellitus and metabolic syndrome, is a risk factor for colorectal cancer has been intensely studied. In fact, even after the conclusion of several prospective studies, the topic is still controversial. We conducted a systematic review and meta-analysis to investigate the dose-response relationship between blood glucose concentration and the incidence of colorectal cancer. A linear (P = 0.303 for non-linearity) dose-response relationship was observed between fasting plasma glucose (FPG) and colorectal cancer risk without significant heterogeneity. The relative risk (RR) for colorectal cancer per 20 mg/dL increase in FPG was 1.015 (95% CI: 1.012–1.019, P = 0.000). In subgroup analyses, the pooled RRs for colon cancer (CC) and rectal cancer (RC) studies were 1.035 (95% CI 1.008–1.062, P = 0.011) and 1.031 (95% CI: 0.189–5.628, P = 0.972), respectively; in the analysis comparing men and women, the pooled RRs were 1.016 (95% CI: 1.012–1.020, P = 0.000) and 1.011 (95% CI: 0.995–1.027, P = 0.164), respectively. Sensitivity analyses using two methods showed similar results. In conclusion, there is a significant linear dose-response relationship between FPG and the incidence risk of colorectal cancer. For people with diabetes or prediabetes, controlling blood glucose might be useful to prevent colorectal cancer.

Epigenetic regulation of the ERβ gene on the estrogen signal transfection pathway in colon cancer cells

We studied the regulatory effects of the estragen receptorβ (ERβ) gene on the downstream estrogen signal transfection pathway in colon cancer cells and the possible mechanisms involved. A human ERβ gene recombinant expression plasmid, pEGFP-C1-ERβ, was constructed and transfected into the Caco-2 colon cancer cell line, a line with low ERβ gene expression. The expression of ERβ mRNA and protein was detected 72 h after transfection. RT-PCR was used to examine the expression levels of the progesterone recepror (PR) gene containing the classic estrogen response element (ERE), the C-fos oncogene containing the AP-1 site (a non-classical ER binding site), the epigenetic modifying genes, such as Dnmt1, Dnmt3a, Dnmt3b, and histone methyltransferase (HMT), and the human mismatch repair gene hMLH1. Methylation-specific PCR was used to detect the changes in the methylated sites of the CpG islands in the promoters of the ERβ, PR, and C-fos genes. The results indicated that the human ERβ gene recombinant expression plasmid pEGFP-C1-ERβ was successfully constructed and transfected into Caco-2 cells. As compared with the control group, the mRNA and protein expression of ERβ gene was increased significantly 72 h after the transfection of pEGFP-C1-ERβ into the Caco-2 cells. As compared with the control group, the mRNA expression of the PR, C-fos, Dnmt3a and Dnmt3b genes was increased significantly 72 h after the transfection of pEGFP-C1-ERβ into the Caco-2 cells, but the mRNA expression of the Dnmt1, HMT, and hMLH1 genes decreased significantly (P<0.05). As compared with the control group, different degrees of demethylation occurred in the promoters of the ERβ, progesterone receptor (PR), and C-fos oncogene 72 h after the transfection of pEGFP-C1-ERβ into the Caco-2 cells. The methylation index of the estrogen signal transfection pathway in Caco-2 cells was decreased significantly following the expression restoration of ERβ gene (P<0.05). It is concluded that the restoration or up-regulation of the ERβ gene in Caco-2 cells may significantly activate the expression of the related target genes in the downstream estrogen signal transfection pathway and may result in the demethylation changes of the pathway. During the process, the expression level and activity of the epigenetic modifying genes and the human mismatch repair gene have changed simultaneously. The regulatory effect of the ERβ gene on the estrogen signal transfection pathway to a certain extent partly involves demethylation.SummaryWe studied the regulatory effects of the estragen receptorβ (ERβ) gene on the downstream estrogen signal transfection pathway in colon cancer cells and the possible mechanisms involved. A human ERβ gene recombinant expression plasmid, pEGFP-C1-ERβ, was constructed and transfected into the Caco-2 colon cancer cell line, a line with low ERβ gene expression. The expression of ERβ mRNA and protein was detected 72 h after transfection. RT-PCR was used to examine the expression levels of the progesterone recepror (PR) gene containing the classic estrogen response element (ERE), the C-fos oncogene containing the AP-1 site (a non-classical ER binding site), the epigenetic modifying genes, such as Dnmt1, Dnmt3a, Dnmt3b, and histone methyltransferase (HMT), and the human mismatch repair gene hMLH1. Methylation-specific PCR was used to detect the changes in the methylated sites of the CpG islands in the promoters of the ERβ, PR, and C-fos genes. The results indicated that the human ERβ gene recombinant expression plasmid pEGFP-C1-ERβ was successfully constructed and transfected into Caco-2 cells. As compared with the control group, the mRNA and protein expression of ERβ gene was increased significantly 72 h after the transfection of pEGFP-C1-ERβ into the Caco-2 cells. As compared with the control group, the mRNA expression of the PR, C-fos, Dnmt3a and Dnmt3b genes was increased significantly 72 h after the transfection of pEGFP-C1-ERβ into the Caco-2 cells, but the mRNA expression of the Dnmt1, HMT, and hMLH1 genes decreased significantly (P<0.05). As compared with the control group, different degrees of demethylation occurred in the promoters of the ERβ, progesterone receptor (PR), and C-fos oncogene 72 h after the transfection of pEGFP-C1-ERβ into the Caco-2 cells. The methylation index of the estrogen signal transfection pathway in Caco-2 cells was decreased significantly following the expression restoration of ERβ gene (P<0.05). It is concluded that the restoration or up-regulation of the ERβ gene in Caco-2 cells may significantly activate the expression of the related target genes in the downstream estrogen signal transfection pathway and may result in the demethylation changes of the pathway. During the process, the expression level and activity of the epigenetic modifying genes and the human mismatch repair gene have changed simultaneously. The regulatory effect of the ERβ gene on the estrogen signal transfection pathway to a certain extent partly involves demethylation.

The prognostic value of AGR2 expression in solid tumours: a systematic review and meta-analysis

The prognostic value of anterior gradient-2 (AGR2) in tumours remains inconclusive. Here, we systematically reviewed the literature evidence and assessed the association between AGR2 expression and prognosis in solid tumours. The primary outcomes were overall survival (OS), disease-specific survival (DSS), and disease-free survival (DFS)/recurrence-free survival (RFS)/progression-free survival (PFS). All analyses were performed by STATA 12.0, with the hazard ratio (HR) or odds ratios (OR), and 95% confidence interval (CI) as the effect size estimate. A total of 20 studies containing 3285 cases were included. Pooled analyses revealed that AGR2 overexpression had an unfavourable impact on OS (HR 1.93, 95% CI 1.32–2.81) and time to tumour progression (TTP) (DFS/RFS/PFS) (HR 1.60 95% CI 1.06–2.40) in solid tumour patients. Subgroup analyses indicated that AGR2 overexpression in breast cancer patients was significantly associated with poor OS (HR 3.02, 95% CI 1.03–8.81) and TTP (HR 1.93, 95% CI 1.17–3.20). Excluding breast cancer, AGR2 overexpression was also found to have a significant correlation with poor OS in the remaining solid tumour patients (HR 1.51, 95% CI 1.04–2.19). Overall, AGR2 might be a potential biomarker to predict prognosis in solid tumour patients.