Remote ischemic perconditioning prevents liver transplantation-induced ischemia/reperfusion injury in rats: Role of ROS/RNS and e NOS

AIM To investigate the underlying mechanisms of the protective role of remote ischemic perconditioning(RIPerC) in rat liver transplantation. METHODS Sprague-Dawley rats were subjected to sham, orthotopic liver transplantation(OLT), ischemic postconditioning(IPostC) or RIPerC. After 3 h reperfusion, blood samples were taken for measurement of alanine aminotransferase, aspartate aminotransferase, creatinine(Cr) and creatinine kinase-myocardial band(CK-MB). The liver lobes were harvested for the following measurements: reactive oxygen species(ROS), H2O2, mitochondrial membrane potential(ΔΨm) and total nitric oxide(NO). These measurements were determined using an ROS/H2O2, JC1 and Total NOx Assay Kit, respectively. Endothelial NO synthase(e NOS) was analyzed by reverse transcription-polymerase chain reaction(RTPCR) and western blotting, and peroxynitrite was semiquantified by western blotting of 3-nitrotyrosine. RESULTS Compared with the OLT group, the grafts subjected to RIPerC showed significantly improved liver and remote organ functions(P < 0.05). ROS(P < 0.001) including H2O2(P < 0.05) were largely elevated in the OLT group as compared with the sham group, and RIPerC(P < 0.05) reversed this trend. The collapse of ΔΨm induced by OLT ischemia/reperfusion(I/R) injury was significantly attenuated in the RIPerC group(P < 0.001). A marked increase of NO content and phosphoserine eN OS, both in protein and mR NA levels, was observed in liver graft of the RIPer C group as compared with the OLT group(P < 0.05). I/R-induced 3-nitrotyrosine content was significantly reduced in the RIPerC group as compared with the OLT group(P < 0.05). There were no significant differences between the RIPerC and IPostC groups for all the results except Cr. The Cr level was lower in the RIPerC group than in the IPostC group(P < 0.01).CONCLUSION Liver graft protection by RIPerC is similar to or better than that of IPostC, and involves inhibition of oxidative stress and up-regulation of the PI3K/Akt/e NOS/NO pathway.

Tumor regression grades:Potential outcome predictor of locally advanced rectal adenocarcinoma after preoperative radiotherapy

AIM:To analyze tumor regression grade(TRG)for prognosis of locally advanced rectal adenocarcinoma(LARA)treated with preoperative radiotherapy.METHODS:One hundred and ninety patients with clinical stageⅡ/ⅢLARA were studied.All patients underwent radical surgery(between 2004 and 2010)after 30-Gy/10-fraction preoperative radiotherapy(preRT).All 190 patients received a short course of preRT and were reassessed for disease recurrence and survival;the slides of surgical specimens were reviewed and classified according to Mandard TRG.We compared patients with good response(Mandard TRG1 or TRG2)vs patients with bad/poor response(Mandard TRG3-5).Outcomes evaluated were 5-year overall survival(OS),5-year disease-free survival(DFS),and local,distant and mixed recurrence.Fisher’s exact test orχ2 test,logrank test and proportional hazards regression analysis were used to calculate the probability that Mandard TRG was associated with patient outcomes.RESULTS:One hundred and sixty-six of 190 patients(87.4%)were identified as Mandard bad responders(TRG3-5).High Mandard grade was correlated with tumor height(41.7%<6 cm vs 58.3%≥6 cm,P=0.050),yp T stage(75%yp T0-2 vs 25%yp T3-4,P=0.000),and yp N stage(75%yp N0 vs 25%yp N1,P=0.031).In univariate survival analysis,Mandard grade bad responders had significantly worse OS and DFSthan good responders(TRG1/2)(OS,83.1%vs 96.4%,P=0.000;DFS,72.3%vs 92.0%,P=0.002).In multivariate survival analysis,Mandard bad responders had significantly worse DFS than Mandard good responders(DFS 3.8 years(95%CI:1.2-12.2 years,P=0.026).CONCLUSION:Mandard grade good responders had a favorable prognosis.TRG may be a potential predictor for DFS in LARA after pre-RT.

High levels of serum platelet-derived growth factor-AA and human epidermal growth factor receptor-2 are predictors of colorectal cancer liver metastasis

AIM To develop predictive markers in blood for colorectal cancer liver metastasis.METHODS Twenty colorectal cancer patients were selected and divided into two groups. Group A consisted of 10 patients whose pathological TNM stage was ⅢC(T3-4N2M0), while another 10 patients with synchronous liver metastasis(TNM stage Ⅳ) were recruited for group B. During the surgical procedure, a 10-ml drainage vein(DV) blood sample was obtained from the DV of the tumor-bearing segment prior to the ligation of the DV. At the same time, a 10-ml peripheral vein(PV) blood sample was collected via peripheral venipuncture. The serum levels of 24 molecules that are potentially involved in the mechanism of liver metastasis in both DV blood and PV blood were analyzed by using high-throughput enzyme-linked immunosorbent assay technology.RESULTS Univariate analysis revealed that platelet-derivedgrowth factor AA(PDGFAA) in DV blood(d PDGFAA)(P = 0.001), PDGFAA in PV blood(p PDGFAA)(P = 0.007), and human epidermal growth factor receptor-2 in PV blood(p HER2)(P = 0.001), p MMP7(P = 0.028), pR ANTES(P = 0.013), and pE GF(P = 0.007) were significantly correlated with synchronous liver metastasis. Multivariate analysis identified d PDGFAA(HR = 1.001, P = 0.033) and p HER2(HR = 1.003, P = 0.019) as independent predictive factors for synchronous liver metastasis. Besides, high peripheral HER2 level may also be a risk factor for metachronous liver metastasis, although the difference did not reach statistical significance(P = 0.06). Significant correlations were found between paired DV and PV blood levels for PDGFAA(r = 0.794, P < 0.001), but not for HER2(r = 0.189, P = 0.424).CONCLUSION PDGFAA in tumor drainage and HER2 in PV blood may be useful predictive factors for synchronous liver metastasis of colorectal cancer.

Phosphatidylinositol 3-kinase CB association with preoperative radiotherapy response in rectal adenocarcinoma

AIM:To examine the correlation of phosphatidylinositol3-kinase(PIK3)CB expression with preoperative radiotherapy response in patients with stageⅡ/Ⅲrectal adenocarcinoma.METHODS:PIK3CB immunoexpression was retrospectively assessed in pretreatment biopsies from 208 patients with clinical stageⅡ/Ⅲrectal adenocarcinoma,who underwent radical surgery after 30-Gy/10-fractionpreoperative radiotherapy.The relation between PIK3CB expression and tumor regression grade,clinicopathological characteristics,and survival time was statistically analyzed.Western blotting and in vitro clonogenic formation assay were used to detect PIK3CB expression in four colorectal cancer cell lines(HCT116,HT29,Lo Vo,and LS174T)treated with 6-Gy ionizing radiation.Pharmacological assays were used to evaluate the therapeutic relevance of TGX-221(a PIK3CB-specific inhibitor)in the four colorectal cancer cell lines.RESULTS:Immunohistochemical staining indicated that PIK3CB was more abundant in rectal adenocarcinoma tissues with poor response to preoperative radiotherapy.High expression of PIK3CB was closely correlated with tumor height(P<0.05),yp T stage(P<0.05),and high-degree tumor regression grade(P<0.001).High expression of PIK3CB was a potential prognostic factor for local recurrence-free survival(P<0.05)and metastasis-free survival(P<0.05).High expression of PIK3CB was also associated with poor therapeutic response and adverse outcomes in rectal adenocarcinoma patients treated with 30-Gy/10-fraction preoperative radiotherapy.In vitro,PIK3CB expression was upregulated in all four colorectal cancer cell lines concurrently treated with 6-Gy ionizing radiation,and the PIK3CB-specific inhibitor TGX-221 effectively inhibited the clonogenic formation of these four colorectal cancer cell lines.CONCLUSION:PIK3CB is critically involved in response to preoperative radiotherapy and may serve as a novel target for therapeutic intervention.

Surgical intervention for malignant bowel obstruction caused by gastrointestinal malignancies

BACKGROUND Malignant bowel obstruction(MBO)is a common event for end-stage gastrointestinal cancer patients.Previous studies had demonstrated manifestations and clinical management of MBO with mixed malignancies.There still lack reports of the surgical treatment of MBO.AIM To analyze the short-term outcomes and prognosis of palliative surgery for MBO caused by gastrointestinal cancer.METHODS A retrospective chart review of 61 patients received palliative surgery between January 2016 to October 2018 was performed,of which 31 patients underwent massive debulking surgery(MDS)and 30 underwent ostomy/by-pass surgery(OBS).The 60-d symptom palliation rate,30-d morbidity and mortality,and overall survival rates were compared between the two groups.RESULTS The overall symptom palliation rate was 75.4%(46/61);patients in the MDS group had significantly higher symptom palliation rate than OBS group(90%vs 61.2%,P=0.016).Patients with colorectal cancer who were in the MDS group showed significantly higher symptom improvement rates compared to the OBS group(overall,76.4%;MDS,61.5%;OBS,92%;P=0.019).However,patients with gastric cancer did not show a significant difference in symptom palliation rate between the MDS and OBS groups(OBS,60%;MDS,80%;P=1.0).The median survival time in the MDS group was significantly longer than in the OBS group(10.9 mo vs 5.3 mo,P=0.05).CONCLUSION For patients with MBO caused by peritoneal metastatic colorectal cancer,MDS can improve symptom palliation rates and prolong survival,without increasing mortality and morbidity rates.

Trans-anal minimally invasive surgery for rectal neoplasia:Experience from single tertiary institution in China

AIM To evaluate the feasibility and safety of trans-anal minimally invasive surgery(TAMIS) from single institute in China. METHODS A retrospective review was conducted for patients with rectal neoplasia, who underwent TAMIS using single incision laparoscopic surgery-Port from January 2013 till January 2016 by a group of colorectal surgeons from Gastrointestinal Center Unit Ⅲ, Peking University Cancer Hospital. Patients' demographic data, surgical related information, post-operational pathology, as well as perioperative follow-up were all collected. RESULTS Twenty-five patients with rectal neoplasia were identified consequently. Complete full-thickness excision was achieved in all cases without conversion. 22(88%) cases had rectal malignancies [6 were adenocarcinomas and 16 were neuroendocrine tumors(NET)], while 3 patients had adenomas. Mean surgical duration was 61.3 min, and mean post-operative stay were 2.7 d. Post-operational examination demonstrated 5 cases had positive resection margin: 2 adenocarcinoma cases and 1 NET case with positive lateral margin, and the other 2 NET cases with positive basal margin. The curve of operation time for TAMIS cases suggested a minimum of 10 cases for a laparoscopic surgeon proficient withthis technique. CONCLUSION TAMIS was demonstrated to be reproducible and safe,with a relatively short learning process for laparoscopic surgeons in selected cases for rectal neoplasia. Longterm oncological outcome needs to be determined by further investigation.

Abelson interactor 1 splice isoform-L plays an anti-oncogenic role in colorectal carcinoma through interactions with WAVE2 and fulllength Abelson interactor 1

BACKGROUND Expression of the full-length isoform of Abelson interactor 1(ABI1),ABI1-p65,is increased in colorectal carcinoma(CRC)and is thought to be involved in one or more steps leading to tumor progression or metastasis.The ABI1 splice isoform-L(ABI1-SiL)has conserved WAVE2-binding and SH3 domains,lacks the homeodomain homologous region,and is missing the majority of PxxP-and Pro-rich domains found in full-length ABI1-p65.Thus,ABI1-SiL domain structure suggests that the protein may regulate CRC cell morphology,adhesion,migration,and metastasis via interactions with the WAVE2 complex pathway.AIM To investigate the potential role and underlying mechanisms associated with ABI1-SiL-mediated regulation of CRC.METHODS ABI1-SiL mRNA expression in CC tissue and cell lines was measured using both qualitative reverse transcriptase-polymerase chain reaction(RT-PCR)and realtime quantitative RT-PCR.A stably ABI1-SiL overexpressing SW480 cell model was constructed using Lipofectamine 2000,and cells selected with G418.Image J software,CCK8,and transwell assays were used to investigate SW480 cell surface area,proliferation,migration,and invasion.Immunoprecipitation,Western blot,and co-localization assays were performed to explore intermolecular interactions between ABI1-SiL,WAVE2,and ABI1-p65 proteins.RESULTS ABI1-SiL was expressed in normal colon tissue and was significantly decreased in CRC cell lines and tissues.Overexpression of ABI1-SiL in SW480 cells significantly increased the cell surface area and inhibited the adhesive and migration properties of the cells,but did not alter their invasive capacity.Similar to ABI1-p65,ABI1-SiL still binds WAVE2,and the ABI1-p65 isoform in SW480 cells.Furthermore,co-localization assays confirmed these intermolecular interactions.CONCLUSION These results support a model in which ABI1-SiL plays an anti-oncogenic role by competitively binding to WAVE2 and directly interacting with phosphorylated and non-phosphorylated ABI1-p65,functioning as a dominant-negative form of ABI1-p65.

Abdominoperineal excision following preoperative radiotherapy for rectal cancer: Unfavorable prognosis even with negative circumferential resection margin

AIM: To evaluate whether an abdominoperineal excision(APE) is associated with increased local recurrence(LR) and shortened disease-free survival(DFS) in mid-low rectal cancer with a negative circumferential resection margin(CRM).METHODS: 283 consecutive cases of mid-low rectal cancer underwent preoperative 30 Gy/10 F radiotherapy and surgery in Peking University Cancer Hospital between August 2003 and August 2009. Patients with positive CRM and intraoperative distant metastasis were precluded according to exclusion criteria. Survival analyses were performed in patients with APE or non-APE procedures.RESULTS: 256 of the 283(90.5%) cases were enrolled in the analysis, including 78(30.5%) and 178(69.5%) cases who received APE and non-APE procedures. Fewer female patients(P = 0.016), lower level of tumor(P = 0.000) and higher body mass index(P = 0.006) were found in the APE group. On univariate analysis, the APE group had a higher LR rate(5.1% vs 1.1%, P = 0.036) and decreased DFS(73.1% vs 83.4%, P = 0.021). On multivariate analysis, APE procedure was also an independent risk factor for LR(HR = 5.960, 1.085-32.728, P = 0.040) and decreased DFS(HR = 2.304, 1.298-4.092, P = 0.004). In stratified analysis for lower rectal cancer, APE procedure was still an independent risk factor for higher LR rate(5.6% vs 0%, P = 0.024) and shortened DFS(91.5% vs 73.6%, P = 0.002).CONCLUSION: Following preoperative 30 Gy/10 F radiotherapy, APE procedure was still a predictor for LR and decreased DFS even with negative CRM. More intensive preoperative treatment should be planned for the candidates who are scheduled to receive APE with optimal imaging assessment.

Long-term follow-up of HER2 overexpression in patients with rectal cancer after preoperative radiotherapy:A prospective cohort study

BACKGROUND The role of HER2 overexpression in rectal cancer is controversial.AIM To assess the role of HER2 overexpression in the long-term prognosis of rectal cancer.METHODS Data from patients with locally advanced rectal cancer who underwent total mesorectal excision after short-course radiotherapy at Beijing Cancer Hospital between May 2002 and October 2005 were collected.A total of 151 tissue samples of rectal cancer were obtained using rigid proctoscopy before neoadjuvant radiotherapy,followed by immunohistochemistry and fluorescence in situ hybridisation to determine the patients’HER2 expression status.Univariate and multivariate analyses of the associations between the clinicopathological factors and HER2 status were performed.Survival was estimated and compared using the Kaplan-Meier method based on HER2 expression status,and the differences between groups were verified using the log-rank test.RESULTS A total of 151 patients were enrolled in this study.A total of 27(17.9%)patients were ultimately confirmed to be HER2-positive.The follow-up duration ranged from 9 mo to 210 mo,with a median of 134 mo.Distant metastasis and local recurrence occurred in 60(39.7%)and 24(15.9%)patients,respectively.HER2 positivity was significantly associated with the pre-treatment lymph node stage(pre-N)(P=0.040),while there were no differences between HER2 status and age,sex,preoperative CEA levels(pre-CEA),T stage,and lympho-vascular invasion.In terms of prognosis,HER2 overexpression was correlated with distant meta stasis(P=0.002)rather than local recurrence(P>0.05).The multivariate analysis demonstrated that elevated pre-CEA[P=0.002,odds ratio(OR)=3.277,97.5%confidence interval(CI):1.543-7.163],post N(+)(P=0.022,OR=2.437,97.5%CI:1.143-5.308)and HER2(+)(P=0.003,OR=4.222,97.5%CI:1.667-11.409)were risk factors for distant metastasis.The survival analysis showed that there were significant differences between rectal cancer patients in terms of disease-free survival(DFS)[hazard ratio:1.69(95%CI:0.91-3.14);P=0.048]and overall survival(OS)[1.95(1.05-3.63);P=0.0077].CONCLUSION HER2 overexpression is a potential biomarker for predicting lymph node metastasis and distant metastasis,which are associated with worse long-term DFS and OS in rectal cancer patients with locally advanced disease.

Total neoadjuvant treatment for MRI-stratified high-risk rectal cancer:a single-center,single-arm,prospective Phase II trial(PKUCH-R02)

Background:Induction chemotherapy combined with neoadjuvant chemoradiotherapy has been recommended for patients with high-risk,locally advanced rectal cancer.However,the benefit of more intensive total neoadjuvant treatment(TNT)is unknown.This study aimed to assess the safety and efficacy of induction chemotherapy combined with chemoradiotherapy and consolidation chemotherapy for magnetic resonance imaging-stratified high-risk rectal cancer.Methods:This was a single-center,single-arm,prospective Phase II trial in Peking University Cancer Hospital(Beijing,China).Patients received three cycles of induction oxaliplatin and capecitabine(CapeOX)followed by chemoradiotherapy and two cycles of consolidation CapeOX.The primary end point was adverse event rate and the second primary end points were 3-year disease-free survival rate,completion of TNT,and pathological downstaging rate.Results:Between August 2017 and August 2018,68 rectal cancer patients with at least one high risk factor(cT3c/3d/T4a/T4b,cN2,mesorectal fascia involvement,or extramural venous invasion involvement)were enrolled.The overall compliance of receiving the entire treatment was 88.2%(60/68).All 68 patients received induction chemotherapy,65 received chemoradiotherapy,and 61 received consolidation chemotherapy.The Grade 3–4 adverse event rate was 30.8%(21/68).Nine patients achieved clinical complete response and then watch and wait.Five patients(7.4%)developed distant metastasis during TNT and received palliative chemotherapy.Fifty patients underwent surgical resection.The complete response rate was 27.9%.After a median follow-up of 49.2 months,the overall 3-year disease-free survival rate was 69.7%.Conclusions:For patients with high-risk rectal cancer,this TNT regimen can achieve favorable survival and complete response rates but with high toxicity.However,it is necessary to pay attention to the possibility of distant metastasis during the long treatment period.

外泌体来源的半乳糖凝集素-9预测肝移植术后排斥发生及预后（英文）

目的:外泌体及其内容物是各种肝脏疾病的潜在生物标志物。本研究探索外泌体及其内容物在肝移植排斥反应及预后中的作用。创新点:本研究发现外泌体及内含物半乳糖凝集素-9(galectin-9)在肝移植术后排斥及预后预测中发挥重要作用。方法:分别从急性排斥和肝功能稳定患者提取外泌体,进行分离、鉴定并检测其内含蛋白。候选蛋白通过在73个急性排斥病人和63个肝功能稳定病人切除肝的组织芯片中进行验证。最后将蛋白表达量和临床参数纳入Kaplan-Meier生存率和Cox回归分析。结论:外泌体来源的galectin-9可作为预测肝移植术后排斥发生及预后的生物学指标。