Circulating cell-free DNA (cfDNA) has emerged as a promising noninvasive diagnostic tool for liquid biopsy, with abnormal DNA methylation serving as a key biomarker for cancer screening and early diagnosis. However, the low abundance and high fragmentation of cfDNA present significant challenges to the sensitivity and specificity of the current methylation detection methods. We aim to develop a highly sensitive methylation detection method for fragmented cfDNA that does not require bisulfite conversion. In this study, we combined double restriction enzyme digestion with specific terminal-mediated polymerase chain reaction (STEM-PCR) to establish a cfDNA methylation detection method, namely, the dRE-STEM method. The dRE-STEM method could detect methylated cfDNA on the PCR platform without the need for cumbersome bisulfite conversion. A case-control study was conducted to validate the diagnostic value of colorectal cancer (CRC)-related specific methylated locates using the dRE-STEM method. The dRE-STEM method successfully detected methylation ratios as low as 3% using just 4 ng of cfDNA input, and the best diagnostic model achieved 80.2% (95% CI, 70.6-87.4%) sensitivity and 80.9% (95% CI, 71.9-87.7%) specificity for CRC, significantly outperforming conventional protein markers. The dRE-STEM method offers a promising approach for accurate methylation quantification in low-abundance, highly fragmented cfDNA, making it particularly suitable for routine clinical practice.

Due to its decade-long progression, colorectal cancer (CRC) is most suitable for population screening to achieve a significant reduction in its incidence and mortality. DNA methylation has emerged as a potential marker for the early detection of CRC. However, the current mainstream methylation detection method represented by bisulfite conversion has issues such as tedious operation, DNA damage, and unsatisfactory sensitivity. Herein, a new high-performance CRC screening tool based on the promising specific terminal-mediated polymerase chain reaction (STEM-PCR) strategy is developed. CRC-related methylation-specific candidate CpG sites are first prescreened through The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases using self-developed bioinformatics. Next, 9 homebrew colorectal cancer DNA methylated STEM‒PCR assays (ColoC-mSTEM) with high sensitivity (0.1%) and high specificity are established to identify candidate sites. The clinical diagnostic performance of these selected methylation sites is confirmed and validated by a case-control study. The optimized diagnostic model has an overall sensitivity of 94.8% and a specificity of 95.0% for detecting early-stage CRC. Taken together, ColoC-mSTEM, based on a single methylation-specific site, is a promising diagnostic approach for the early detection of CRC which is perfectly suitable for the screening needs of CRC in primary healthcare institutions.

Cancer vaccines combined with immune checkpoint blockades (ICB) represent great potential application, yet the insufficient tumor antigen presentation and immature dendritic cells hinder improved efficacy. Here, a hybrid nano vaccine composed by hyper branched poly(beta-amino ester), modified iron oxide nano adjuvant and messenger RNA (mRNA) encoded with model antigen ovalbumin (OVA) is presented. The nano vaccine outperforms three commercialized reagents loaded with the same mRNA, including Lipofectamine MessengerMax, jetPRIME, and in vivo-jetRNA in promoting dendritic cells' transfection, maturation, and peptide presentation. In an OVA-expressing murine model, intratumoral administration of the nano vaccine significantly induced macrophages and dendritic cells' presenting peptides and expressing co-stimulatory CD86. The nano vaccine also elicited strong antigen-specific splenocyte response and promoted CD8+ T cell infiltration. In combination with ICB, the nano vaccine aroused robust tumor suppression in murine models with large tumor burdens (initial volume >300 mm3 ). The hybrid mRNA vaccine represents a versatile and readily transformable platform and augments response to ICB.

Our previous work suggested that high SIRT1 expression by cancer cells predicted a poor colorectal cancer (CRC) prognosis, but its role in the tumor microenvironment was unclear. Here, we examined tumor-infiltrating lymphocytes (TILs) in CRC expressing different levels of SIRT1. We also established a co-culture system with monocytes, CD8+ T cells and patient-derived tumor organoids (PDOs) to study the relationships between immune cells and cancer cells. The percentage of CD8+ T cells was decreased and the percentage of macrophages was increased in SIRT1-high (SIRT1-hi) CRC. Co-culture results showed that tumor-associated macrophages (TAMs) from SIRT1-hi CRC inhibited the proliferation and anti-tumor activity of CD8+ T cells. Importantly, SIRT1-hi CRC were shown to modulate the migration and the activity of TAMs. RNA sequencing revealed that CD14+ monocytes in SIRT1-hi patients expressed higher levels of CXCR4. Mechanistically, SIRT1 expression was shown to promote CXCL12 expression by inhibiting the acetylation of p53. Our findings indicate that SIRT1 in CRC induces TAM migration through the CXCR4/CXCL12 pathway, and inhibits the proliferation and activity of CD8+ T cells, resulting in promotion of CRC progression.

Highly sensitive and specific detection of DNA methylation is critical for early diagnosis and therapy of cancer. Herein, we propose a novel bisulfite-free PCR assay based on a GlaI methylation specific digestion and terminal transferase (TdT) extension for the detection of methylated DNA with high sensitivity and specificity, denoted as GlaI-TdT methylation PCR. For GlaI-TdT methylation PCR assay, the methylated CpG site is recognized and cut by GlaI selectively firstly, leading to the generation of product with specific free 3' end. The free 3' end can be further extended with TdT and served as template for the followed quantitative PCR. The specificity of GlaI-TdT methylation PCR depends on the specific methylation discrimination of GlaI and the existence of poly-T sequence as the extension of TdT. The sensitivity of GlaI-TdT PCR for methylated DNA can achieve 10 copies/reaction with 10,000 copies unmethylated background. The detection performance of GlaI-TdT methylation PCR was also evaluated using colorectal cancer tissue samples, with the results shown great accordance with standard bisulfite-PCR sequencing. Based on its high sensitivity, high specificity, simple and convenient, GlaI-TdT methylation PCR has the great potential to become a promising and robust bisulfite-free procedure for the detection of DNA methylations.

Introduction Anastomotic leakage (AL) is generally accepted as a major complication of rectal resection surgery. However, there is still debate about the definition and evaluation of AL. The International Study Group of Rectal Cancer (ISREC) raised a definition of and grading system for AL in 2010. Aim In our study, we aimed to validate AL's present definition and grading system, which were proposed by ISREC in 2010. Methods Patients who underwent rectal anterior resection in 2 colorectal surgery centers from January 2012 to December 2014 were included and categorized into different groups according to the ISREC criteria; further, the rate, severity and clinical outcomes of their ALs were analyzed and compared. Results During a median follow-up period of 38.9 months, 984 patients were included in total. The overall AL rate was 5.0% (49/984), including 7 grade A patients (14%), 21 grade B patients (43%), and 21 grade C patients (43%). The rate of grade C AL in the protective diverting stoma group was significantly lower than that in the nonstoma group (0.6% versus 2.8%, P = 0.029). Patients with grade B or grade C AL had much longer hospital stays than grade A AL patients (P = 0.016). The overall 3-year survival rates of grades A, B, and C groups were 83.3%, 66.7% and 55.6% respectively, without statistical significance. Conclusions Patients who were divided into different groups according to the grading system proposed by the ISREC criteria had significantly different symptoms, clinical outcomes, management, and duration of hospitalization. Our study supported that the ISREC criteria are a simple but valid classification to evaluate the surgical performance of the rectal cancer resection.

Background: Preservation of the left colic artery in low-tie (LT) of inferior mesenteric artery remains controversial compared to high-tie (HT) in the colon and rectal cancers, for lymph node dissection, anastomotic leakage, and oncological outcome. This cohort study aims to analyze short- and long-term outcomes of laparoscopic anterior resections in LT vs HT for rectal cancers. Methods: We analyzed a cohort of laparoscopic AR for RC from 2013 to 2016 at Renji Hospital, Shanghai, China. Short- and long-term outcome in LT vs HT group were compared for clinico-demographic characteristics, operative-time, lymph node dissection, short-term 30-day outcome, and long-term 3- and 5-year overall survival as well as disease-free survival. The x(2), t-test, and logistic regressions analysis were used and p<0.05 was considered significant. Results: The cohort consisted of 614 laparoscopic AR with LT (236) and HT (378). The clinicodemographic characteristics were comparable among the groups. The surgery took longer in LT. The yield of LND was similar. Leakage occurred in 12.21% (n=75). Leakage was fewer in LT than HT, 8.89% vs 14.28%, p=0.047. The postoperative severe complications were higher in HT. The 30-day mortality was nil. The long-term 3- and 5-year overall survival and disease-free survival were similar in LT and HT. Conclusion: The LT with preservation of left colic artery had similar lymph node yield, but lower leakage and complications than HT in laparoscopic anterior resections for rectal cancers. The long-term 3- and 5-year overall and disease-free survival were similar in the two groups.

Patient-derived organoids (PDOs) closely recapitulate human colorectal cancer biology and have recently emerged as preclinical models for personalized therapy design.1 However, PDOs cultured in Matrigel (PDOsMatrigel) failed to predict outcome for treatment with the first-line FO chemotherapeutic regimen (5-fluorouracil plus oxaliplatin) for metastatic colorectal cancer (mCRC) patients.2 In this study, we establish in vitro culture conditions of mCRC-PDOs in a hydroxypropyl cellulose allyl conjugated with collagen (HA-Coll sponge),3 and utilized this system to examine the drug sensitivity of FO regimen (Figure 1A). A total of 12 tumor organoid cultures from metastatic lesion were developed from 12 patients enrolled in Renji hospital between September 2018 and October 2019 (Table S1). In the HA-Coll sponge, the primary tumor cells organized into 3D spheroids within 3 days, although its size was smaller than that of organoid grown in Matrigel, and continues to grow until reaching similar sizes at about day 7 and its size was relative homogeneous (Figure 2A, Figure S1A and B). PDOs in HA-Coll sponge (PDOsSponge) proliferated at the same level as PDOsMatrigel in the next generation (Figure 2B and C, Figure S1C and D). H&E staining showed notable morphological similarity among PDOsSponge and parental patient biopsies, and the “cystic versus solid” structure of the epithelium were preserved (Figure 2D, Figure S1E); the typical expression pattern of CDX-2 (caudal type homeox-2) and CK7 (keratin 7) in CRC was observed in PDOsSponge (Figure S1F). Collectively, the mCRC-PDOs were successfully cultured in HA-Coll sponge. To explore whether PDOsSponge keep the genetic characteristics of the parental tumor, the next-generation sequencing (NGS) was used to examine 561 cancer-related genes in 12 pairs of PDOsSponge and their parental tumor tissues. The molecular landscape of the PDOsSponge largely overlapped with parental tumor and a 74% overlap in mutational spectrum was observed between these two groups (Figure 2E, Table S2), indicating that the major mCRC molecular genotypes are represented in PDOsSponge. Next, we examined the predictive value of mCRC-PDOsSponge on FO regime by comparisons of their ex vivo response data with clinical responses in patients. Twelve patients enrolled in our study were applied with FO therapy in clinic and the PDOsSponge were established from the biopsy before the treatment (Table S1, Figure 3A and Figure S2). The PDOsSponge were treated with different concentrations of 5-FU and oxaliplatin, and after 6 days the growth rates were examined by Cell-Titer Glo2.0 assay. We fitted dose–response curves (DRCs) and quantified responses to FO by calculating the IC50 and the area under the DRC (AUCDRC), both of which were significantly different between PDOsSponge from PR/SD versus PD lesions (Figure 3B–D). However, there were no significant difference on IC50 or AUCDRC in the PDOs cultured in Matrigel (Figure 3E–G). In addition to FO regimen, irinotecan-based chemotherapy is also used for CRC patients as second-line regimen.4 Figure S3 showed that there were no significant differences on IC50 between PDOsSponge and PDOsMatrigel, suggesting that the distinction of these two groups mainly reflect the clinical response to FO chemotherapy but not irinotecan-based regimen and highlighted the clinical potential of PDOsSponge for FO therapeutic selection in mCRC. Epithelial to mesenchymal transition (EMT) has been demonstrated to play important roles in therapeutic resistance,5 so we wondered if EMT was involved in the differential drug-sensitivity between PDOsSponge and PDOsMatrigel. First, the expression of E-cadherin in PDOs and the parental tumors from PR patients was examined by immunofluorescence and the results showed that PDOsSponge had similar expression level of E-cadherin as their correspondent parental tissues, while it was dramatically decreased in PDOsMatrigel (Figure 4A, Figure S4A). These results were confirmed by the data of western blotting (Figure S5A-H) and by the qPCR results of other EMT-related makers (Figure S5I). In addition, activation of the EMT usually elicits changes in cell morphology6 and the results of the transmission electron microscopy (TEM) demonstrated that cell–cell junctions were observed in both PDOsSponge and parental biopsies, while the intercellular connections in the PDOsMatrigel were much looser and minimal (Figure 4B, Figure S4B). Next, we utilized EMT inhibitors, methacycline HCl or (E)-SIS3, to inhibit the progression of EMT (Figure S6A–C) and the ex vivo drug-sensitivity experiments showed that, after adding methacycline HCl, the IC50 values of FO in PDOsMatrigel were significantly reduced (Figure 4C, Figure S4C). The same tendency was also observed in those treated with (E)-SIS3 (Figure 4D, Figure S4D), suggesting that blocking EMT in PDOsMatrigel could recover its drug-sensitivity in FO chemotherapy; however, this recovery was not observed in irinotecan-treated groups (Figure S6D and E). Whether EMT inhibitors could be used in PDO culture for drug screening will need more experiments to confirm, particularly in different chemotherapeutic drug combination. Conclusively, our results indicated that PDOsSponge remained the original epithelial state of parental tumor tissues, which is important for the drug-sensitivity of FO, but not for irinotecan. The epithelial state of cells usually reflected their differential states,7 so we used CD133 and CD26 antibodies to examine the percentage of CSCs in the PDOs by flow cytometry. Figure 4E and Figure S4E demonstrated that the percentage of CD133+ cells in PDOsMatrigel was obviously higher than those in PDOsSponge and parental tumor tissue, although CD26 maybe was not proper marker for CSCs in our experiments. Mechanical tension on a cell from its environment control gene expression to modulate tissue-specific differentiation8 and stiff environment could increase the transcription of lamin-A to alter nuclear rheology, thereby promoting cell differentiation.9 To figure out if lamin-A was involved in keeping the epithelial state in PDOsSponge, the expression level of lamin-A in nuclear proteins was examined by western blotting. Figure 4F and Figure S4F showed that the expression of lamin-A was dramatically decreased in PDOsMatrigel, but not in PDOsSponge, which was consistent with the previous studies that the matrix stiffness of Sponge3 is at the similar level to that of intestinal epithelial cells.10 Next we added retinoic acid (RA) to inhibit the expression level of lamin-A in PDOsSponge (Figure 4F, Figure S4F),9 and thereby enhance the percentage of CSCs in PDOsSponge (Figure 4E, Figure S4E), consequently, the IC50 value of FO in PDOsSponge was dramatically increased by RA (Figure 4G, Figure S4G). To further confirm these results, we knocked out LMNA in PDOsSponge and overexpressed LMNA in PDOsMatrigel to perform the drug response assay. The same tendency with RA results was observed (Figure 4H and I, Figure S7), suggesting that lamin-A contributes to the epithelial state of PDOsSponge. In summary, we reported that the mCRC-PDOsSponge could recapitulate the phenotype and genotype of the parental tumor tissue. PDOsSponge could keep the similar expression level of lamin-A as their parental tumor tissues, maintain the epithelial state of colorectal epithelial cell, and predict drug responses to FO chemotherapeutic regimen (Figure 1B). The work reported here is supported by grants from the National Natural Science Foundation of China (81773250 and 81972670 to Y. Zhang; 81873555 and 81672347 to M. Zhong) and Technology Cooperation Program of Shanghai (18410741700 to J. Chen). The authors declare that they have no conflict of interest. Yan Zhang and Yanjie Xu: Conceptualization, methodology, and writing and original draft preparation. Jianjun Chen and Ming Zhong: Funding acquisition and data curation. Yizhou Huang and Yang Luo: Resources, visualization, and investigation. An-Chih Hsieh and Jianyi Chen: Resources. Han Li: Software and validation. Xunbin Wei, Wei-Qiang Gao, and Ming Zhong: Project administration and supervision. Yanjie Xu and Yan Zhang: Writing, reviewing, and editing. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Absent in melanoma 2 (AIM2), a DNA sensor that plays an important role in natural immunity system, has been reported to participate in colorectal cancer (CRC) development. However, the functional role of AIM2 in BRAF-mutant CRC remains unclear. In this study, we first investigated AIM2 expression level in BRAF-mutant CRC tumor tissues. Overexpression of AIM2 in CRC cells was performed to investigate the effect of AIM2 on CRC cell viability, and cell death detection and caspase activity assay were performed to explore the mechanism that AIM2 impacts the growth of BRAF-mutant CRC cells. Moreover, we confirmed the antitumor effect of AIM2 in BRAF-mutant CRC cell-derived tumor xenograft (CDX) models as well as patient-derived organoids (PDOs). Herein, we reported that AIM2 expression was lower in BRAF-mutant than that in BRAF wild-type CRC tumor tissues. Restoring the expression of AIM2 in BRAF-mutant CRC cells greatly inhibits the tumor cell growth by inducing necrotic cell death. Mechanism studies revealed that AIM2-induced cell death is in a caspase-1-dependent manner. Additionally, overexpression of AIM2 significantly inhibits tumor growth and metastasis in BRAF-mutant CRC in vivo, which was further confirmed in BRAF-mutant CRC PDOs. Taken together, our data suggested that AIM2 inhibits BRAF-mutant colon cancer growth in a caspase-1-dependent manner, which may provide evidence to understand the pathogenesis of CRC with BRAF-mutant, as well as new strategies for manipulation of CRC.

目的:探讨结直肠外科专业化程度对腹腔镜低位直肠癌手术中行预防性造口的影响.方法:采用回顾性队列研究方法,收集2017年1月至2020年6月收治并经病理确诊的107例腹腔镜低位直肠癌手术患者的临床资料,分为专业组(n=57例)与非专业组(n=50例).观察两组术中情况、术后吻合口漏及其他并发症发生情况.结果:两组术中出血量差异无统计学意义(P=0.69).专业组手术时间[(124.9±4.22)min vs.(150.1±4.81)min]、预防性造口率(29.8％vs.58.0％)小于非专业组,淋巴结清扫数量[(12.21±0.26)枚vs.(10.90±0.31)枚]多于非专业组,差异有统计学意义(P<0.01).术后21例(19.6％)患者发生吻合口漏,专业组与非专业组术后总体吻合口漏发生率(17.5％vs.22.0％,P=0.56)差异无统计学意义;但预防性造口患者中专业组吻合口漏发生率(47.1％vs.17.2％,P=0.001)高于非专业组;而在非预防性造口患者中专业组吻合口漏发生率(6.7％vs.28.6％,P=0.03)低于非专业组.两组术后尿潴留、切口感染、肺部感染、肠梗阻发生率差异均无统计学意义(P>0.05).结论:腹腔镜低位直肠癌前切除术中专业化的外科治疗可更加合理地选择预防性造口,减少预防性造口的例数.

Background Early detection of capecitabine-resistance could largely increase overall survival of colorectal cancer (CRC) patients. Previous studies suggested examination of immune cells in peripheral blood would help to predict efficacy of chemotherapy. Methods We examined the immunological characteristics of peripheral blood in CRC patients with capecitabine treatment. We analyzed the relationships between the abnormal immune cell population in capecitabine-resistance patients and major clinical features. Furthermore, RNA sequencing, analyses of cell surface marker expression and the correlations with other major immune cell populations were performed using this population to explore the possible function of these cells. Results The expression level of CD16 on neutrophils was down-regulated in capecitabine-resistant CRC patients. Patients with CD16 low/− neutrophils after capecitabine therapy had adverse clinical features. What’s important, the change of CD16 expression level on neutrophils appeared much earlier than CT scan. RNA sequencing revealed that CD16 low/− neutrophils in capecitabine-resistant patients had lower expression level of neutrophil-related genes, compared to CD16 + neutrophils in capecitabine-sensitive patients, suggesting this CD16 low/− population might be immature neutrophils. Furthermore, the expression level of CD16 on neutrophils in patients with capecitabine treatment was positively correlated with the number of anti-tumor immune cell subsets, such as CD8 + T cell, CD4 + T cell, NK cell and monocyte. Conclusions Our findings indicated that CD16 expression on neutrophils in peripheral blood was a good prognostic marker for predicting efficacy of capecitabine in CRC patients.

Objective: To compared the short-term surgical outcomes of the vertical supraumbilical incision with the left lower oblique incision for specimen retrieval in laparoscopic resection for rectal cancer. Methods: A retrospective cohort study was performed. Inclusion criteria: (1) rectal cancer confirmed by colonoscopy and pathological examination; (2) undergoing the operation for the first time; (3) laparoscopic rectal surgery performed by the same surgeon team; (4) age of > 18 years and < 76 years old. According to above criteria, clinical data of 178 consecutive patients scheduled for laparoscopic surgery for rectal cancer at Department of Gastrointestinal Surgery of Renji Hospital between March 2015 and December 2017 were collected. Based on incision site of the mini-laparotomy, patients were classified to the vertical supraumbilical incision group (n=75) and the left lower oblique incision group (n=103). There were no significant differences in baseline data, such as age, gender, body mass index (BMI), tumor diameter, preoperative carcinoembryonic antigen (CEA) level, score of American Society of Anesthesiologists, TNM stage, between the two groups (all P>0.05). Perioperative variables and follow-up data were compared between two groups. Results: Between the vertical supraumbilical incision group and the left lower oblique incision group, the operation time [(131.7±3.7) minutes vs. (138.5±3.5) minutes], operative bleeding volume [(138.9±11.5) ml vs. (154.3±10.3) ml], length of auxiliary incision [(4.0±0.1) cm vs. (4.0±0.1) cm], and distance from anastomosis to dentate line [(3.8±0.1) cm vs. (4.2±0.1) cm] were not significantly different (all P>0.05). As compared to the left lower oblique incision group, patients in vertical supraumbilical incision group had earlier flatus [(62.7±2.3) hours vs. (69.2±1.7) hours, t=2.282, P=0.023], earlier ambulation [(41.9±1.8) hours vs. (46.78±1.42) hours, t=2.131, P=0.032], lower pain VAS scores at postoperative 24 hours (2.0±0.1 vs. 2.4±0.1, t=2.172, P=0.032) and 48 hours (2.7±0.1 vs. 3.0±0.1, P<0.05), and lower incidence of postoperative incisional hernia [6.7% (5/75) vs. 9.7% (10/103), χ(2)=3.942, P=0.042]. However, the postoperative fluids intake time, hospitalization days, pain VAS scores at postoperative 12 hours and postoperative complications (wound infection, anastomotic leakage, urinary retention, intestinal obstruction) were not significantly different between the two groups (all P>0.05). Conclusion: The vertical supraumbilical incision in laparoscopic resection for rectal cancer can reduce the degree of postoperative pain, facilitate early recovery of intestinal function and decrease the incidence of incisional hernia.

目的 通过比较放置吻合口支架与单纯手工缝合对大鼠结肠吻合口漏的影响,探索吻合口支架对降低结肠术后吻合口漏发生率的应用价值.方法 以32只雄性SD大鼠为研究对象,随机分为2组,每组16只,行大鼠结肠端端吻合术,实验组行间断缝合的同时放置支架,即支架组;对照组单纯行间断缝合,即手工缝合组.比较两组腹腔粘连程度、吻合口漏、总生存率的差异.结果 相对于手工缝合组,支架组吻合腹腔粘连程度评分较低(5.94±1.69 vs.9.19±2.52,t=4.181;P=0.008);支架组吻合口漏发生率明显低于手工缝合组(12.5％vs.56.25％,χ2=6.788;P=0.023);支架组总生存率高于手工缝合组(87.5％vs.43.75％,χ2=5.850;P=0.016).结论 相对于手工缝合,吻合口支架可以减少大鼠术后腹腔粘连程度,降低吻合口漏发生率,具有潜在临床应用价值.

Ulcerative colitis (UC) is a multifactorial inflammatory disease, and increasing evidence has demonstrated that the mechanism of UC pathogenesis is associated with excessive cellular apoptosis and reactive oxygen species (ROS) production. However, their function and molecular mechanisms related to UC remain unknown. In this study, Rab27A mRNA and protein were proven to be overexpressed in intestinal epithelial cells of UC patients and DSS‐induced colitis mice, compared with control ( P < 0.05). And Rab27A silencing inhibits inflammatory process in DSS‐induced colitis mice ( P < 0.05). Then, it was shown that knockdown of Rab27A suppressed apoptosis and ROS production through modulation of miR‐124‐3p, whereas overexpression of Rab27A promoted apoptosis and ROS production in LPS‑induced colonic cells. In addition, enhanced expression of miR‐124‐3p attenuated apoptosis and ROS production by targeting regulation of STAT3 in LPS‑induced colonic cells. Mechanistically, we found Rab27A reduced the expression and activity of miR‐124‐3p to activate STAT3/RelA signalling pathway and promote apoptosis and ROS production in LPS‑induced colonic cells, whereas overexpression of miR‐124‐3p abrogated these effects of Rab27A. More importantly, animal experiments illustrated that ectopic expression of Rab27A promoted the inflammatory process, whereas overexpression of miR‐124‐3p might interfere with the inflammatory effect in DSS‐induced colitis mice. In summary, Rab27A might modulate the miR‐124‐3p/STAT3/RelA axis to promote apoptosis and ROS production in inflammatory colonic cells, suggesting that Rab27A as a novel therapeutic target for the prevention and treatment of UC patients.

近年,腹腔镜直肠癌手术在临床上得到广泛应用,国内外多家医学机构通过大量研究肯定了腹腔镜直肠癌手术的可行性与有效性[1].但吻合口漏仍是直肠癌手术后常见且严重影响患者康复、生命质量的并发症,而预防性转流术是减少吻合口漏所致并发症最有效的方式[ 2-3].但其严重影响了患者的术后生活质量,增加了二次手术的风险.由于吻合口漏影响因素较多,临床上往往难以预测患者的吻合口漏风险,初期手术时是否行预防性转流术是困扰许多外科医生的问题.

Background: Robot-assisted surgical techniques have been introduced in recent years as an alternative minimally invasive approach for colorectal surgery. In practice, we found that the monopolar electrosurgical scissors had its unique advantages in preservation of the pelvic autonomic nerves. We performed a retrospective review of short-term results between using monopolar electrosurgical scissors and harmonic scalpel in robotic anterior resection (using the da Vinci (R) Surgical System) in rectal cancer patients. Method: Forty-six patients who underwent robotic anterior resection of rectal cancer from June 2016 to January 2018 were retrospectively analyzed and compared. Twenty-two cases underwent resection using monopolar electrosurgical scissors and 24 cases underwent resection using the harmonic scalpel. Patient characteristics, perioperative clinical results, complications, and pathological results were compared between two groups. Results: There were not significantly different patient characteristics between the two groups. The mean operative time was lesser in the monopolar electrosurgical scissors group than in the inharmonic scalpel group [95.59 +/- 21.44 minutes versus 81.45 +/- 13.89 minutes, P < .01]. The mean estimated blood loss was lesser in the monopolar electrosurgical scissors group than in the inharmonic scalpel group [48.64 +/- 19.35 mL versus 61.82 +/- 24.23 mL, P = .03]. The complication rate was 18.2% in the monopolar electrosurgical scissors group and 16.7% in the harmonic scalpel group (P = .89). The mean time of postoperational urinary catheter was lesser in the monopolar electrosurgical scissors group [3.73 +/- 1.16 days versus 4.59 +/- 1.71 days, P = .02]. The day to first passing flatus [3.45 +/- 0.80 days versus 3.59 +/- 1.14 days, P = .67], feeding time [4.50 +/- 1.00 days versus 4.05 +/- 1.87 days, P = .35], hospital stay [8.18 +/- 3.74 days versus 8.68 +/- 3.44 days, P = .52], and the mean number of harvested lymph nodes of detection [13.59 +/- 1.71 versus 13.77 +/- 1.41, P = .67] were comparable between procedures. Conclusion: Monopolar electrosurgical scissors were used safely and effectively in robotic anterior resection of rectal cancer (using the da Vinci Surgical System). The use of monopolar electrosurgical scissors has benefits in performing blunt and sharp separation in narrow pelvic and cheaper hospitalization expenses.

The tartrate-resistant acid phosphatase (TRAP/ACP5) correlated with tumor progression in many malignancies. However, the role of ACP5 in colorectal cancer (CRC) has not been thoroughly elucidated. In this study, we sought to identify the role for ACP5 in CRC progression. Immunohistochemistry revealed that high ACP5 expression is positively associated with tumor size, tumor classification, lymph node metastasis, distant metastasis and advanced stage cancer in 285 CRC patients. Moreover, high ACP5 expression was significantly associated with poor overall survival and disease-free survival. Then, ectopic expression of ACP5 promoted tumor cell proliferation and invasion, whereas suppression of ACP5 expression resulted in decreased cell proliferation and invasion in colorectal cell lines in vitro. And, inhibition of ACP5 also inhibited growth of engrafted tumors in vivo. Furthermore, we found that ACP5 overexpression positively regulated p-FAK, p-PI3K and p-AKT in CRC cells. ACP5 depletion showed the opposite effects. What's more, overexpression of FAK in CRC cells could restore the reduced abilities of cell proliferation and invasion caused by siRNAs-ACP5. Finally, we found the inhibition of activity by Akt inhibitors, MK2206, could partially decrease the positive effects of ACP5 on CRC cell proliferation and invasion. In conclusion, our results suggest that overexpressed ACP5 might serve as an indicator for poor prognosis in colorectal cancer patients through regulation of FAK/PI3K/AKT signaling pathway, which might be a potential therapeutic approach for colorectal cancer therapy.

Background Colorectal cancer (CRC) is one of the high incidences tumours and is ranked second in cancer-related mortality. Even though great progress has been made, there are no effective therapeutic strategies for late stage and metastatic CRC patients. Acidity is one characteristic of the tumour microenvironment. However, how cancer cells respond to this acidic environment surrounding them remains largely unknown, especially in colorectal cancer. Methods Proton sensor receptor expression was analysed in GEO and TCGA datasets. The expression of GPR4 in CRC specimens was confirmed by western blotting and immunohistochemistry (IHC). The role of GPR4 in CRC progression was analysed both in vitro and in vivo. Pharmacological intervention, immunofluorescence and gene set enrichment analyses were performed to reveal the underlying molecular mechanisms of GPR4. Findings We found that GPR4 was upregulated in CRC samples. In addition, its high expression correlated with late stage tumours and poor overall survival in patients. Furthermore, loss-of-function assays proved that GPR4 promoted CRC carcinogenesis and metastatic ability. Mechanistically, GPR4 was activated by extracellular protons in the tumour microenvironment and enhanced RhoA activation and F-actin rearrangement, leading to LATS activity inhibition, YAP1 nuclear translocation and oncogene transcription. Interpretation The expression of GPR4 is upregulated in colorectal cancer and is associated with shorter overall survival time in CRC patients. These findings reveal the novel roles of GPR4 in CRC progression and suggest GPR4 might be a new therapeutic target for CRC treatment.

Crohn's disease (CD) is a chronic non-specific intestinal inflammatory disease, and the incidence of perianal fistulizing CD (PFCD) is 17%-43%. Non-cutting setons is the first choice for surgical treatment of PFCD. Some new surgical methods are effective for specific types of PFCD, however, the efficacy of most new methods remains to be confirmed by further studies. The multidisciplinary team (MDT) mode has become a new direction of PFCD surgery. This article reviewed the advances in surgical treatment of PFCD.

Objective To compare the short-term and long-term outcomes between laparoscopic and open total proctocolectomy with ileal pouch-anal anastomosis (IPAA) for ulcerative colitis (UC).Methods The retrospective cohort study was conducted.The clinical data of 150 UC patients who underwent total proctocolectomy with IPAA in the Renji Hospital of Shanghai Jiaotong University between January 2003 and December 2016 were collected.Among 150 patients,87 undergoing laparoscopic total proctocolectomy with IPAA and 63 undergoing open total proctocolectomy with IPAA were respectively allocated into the laparoscopy group and open group.Observation indicators:(1) comparisons of intra-and post-operative situations;(2) postoperative complications;(3) follow-up situation.Follow-up using outpatient examination and telephone interview was performed to detect postoperative recovery and complications up to December 2017.Measurement data with normal distribution were represented as x-±s and comparison between groups was analyzed using the t test.Comparison between groups of count data was analyzed using the chi-square test.Results (1) Comparisons of intra-and post-operative situations:operation time,volume of intraoperative blood loss,time of initial intestinal stoma exsufflation and duration of hospital stay were respectively (306±3) minutes,(197± 12) mL,(62.1±1.8) hours,(8.2±0.4) days in the laparoscopy group and (224±4) minutes,(308±24) mL,(75.6±2.0) hours,(10.1±0.6) days in the open group,with statistically significant difference between groups (t =16.23,4.33,5.03,2.61,P＜ 0.05).All patients discharged successfully from hospital.All the 150 patients underwent stoma reversion of ileum at 3-12 months postoperatively,and the average time in the laparoscopy group and open group was respectively (6.0±5.6) months and (6.0±4.6)months,with no statistically significant difference between groups (t =0.01,P＞ 0.05).(2) Postoperative complications:cases with postoperative wound infection,retention of urine and frequency of defecation ＞ 4 times / day were respectively 2,8,21 in the laparoscopy group and 8,15,29 in the open group,with statistically significant differences between groups (x2 =5.25,4.37,0.96,P＜0.05).The cases with postoperative intestinal obstruction,anastomotic leakage,pelvic infection,pouch infection,pouch-related Crohn's disease and hyperplasia of ileal pouch were respectively 3,10,5,23,2,1 in the laparoscopy group and 8,7,4,24,1,0 in the open group,with no statistically significant differences between groups (x2=3.65,0.11,0.01,0.96,0.17,0.82,P＞0.05).Patients with postoperative complications were improved by acid suppression,fasting,anti-infection and fluid infusion.(3) Follow-up situation:150 patients were followed up for 12-60 months,with a median time of 48 months.There was no abnormality of postoperative anastomotic stoma and intestinal mucosa through comparison of colonoscopy results between pre-operation and 5 year postoperatively.During the follow-up,50 patients had shapeless stool and irregular defecation (times ＞ 4 times / day) at 3 years after stoma reversion of small intestine bypass,including 21 in the laparoscopy group and 29 in the open group,with a statistically significant differences between groups (x2 =4.72,P＜0.05).Eleven and 10 patients in the laparoscopy group and open group had shapeless stool and irregular defecation at 5 years postoperatively,but status were improved compared with the preoperative status,with no statistically significant difference between groups (x2=0.32,P ＞ 0.05).Conclusion The security of laparoscopic total proctocolectomy with IPAA for UC is equivalent to that of open total proctocolectomy,with the better short-term and long-term outcomes.