Adipose-derived stem cells promote glycolysis and peritoneal metastasis via TGF-ß1/SMAD3/ANGPTL4 axis in colorectal cancer.

Peritoneal metastasis, the third most common metastasis in colorectal cancer (CRC), has a poor prognosis for the rapid progression and limited therapeutic strategy. However, the molecular characteristics and pathogenesis of CRC peritoneal metastasis are poorly understood. Here, we aimed to elucidate the action and mechanism of adipose-derived stem cells (ADSCs), a prominent component of the peritoneal microenvironment, in CRC peritoneal metastasis formation. Database analysis indicated that ADSCs infiltration was increased in CRC peritoneal metastases, and high expression levels of ADSCs marker genes predicted a poor prognosis. Then we investigated the effect of ADSCs on CRC cells in vitro and in vivo. The results revealed that CRC cells co-cultured with ADSCs exhibited stronger metastatic property and anoikis resistance, and ADSCs boosted the intraperitoneal seeding of CRC cells. Furthermore, RNA sequencing was carried out to identify the key target gene, angiopoietin like 4 (ANGPTL4), which was upregulated in CRC specimens, especially in peritoneal metastases. Mechanistically, TGF-ß1 secreted by ADSCs activated SMAD3 in CRC cells, and chromatin immunoprecipitation assay showed that SMAD3 facilitated ANGPTL4 transcription by directly binding to ANGPTL4 promoter. The ANGPTL4 upregulation was essential for ADSCs to promote glycolysis and anoikis resistance in CRC. Importantly, simultaneously targeting TGF-ß signaling and ANGPTL4 efficiently reduced intraperitoneal seeding in vivo. In conclusion, this study indicates that tumor-infiltrating ADSCs promote glycolysis and anoikis resistance in CRC cells and ultimately facilitate peritoneal metastasis via the TGF-ß1/SMAD3/ANGPTL4 axis. The dual-targeting of TGF-ß signaling and ANGPTL4 may be a feasible therapeutic strategy for CRC peritoneal metastasis.

Linear-Array Endoscopic Ultrasound and Narrow-Band Imaging Measure the Invasion Depth of Nonpedunculated Rectal Lesions With Comparable Accuracy Based on a Randomized Controlled Trial.

INTRODUCTION: Linear-array endoscopic ultrasound (EUS) and narrow-band imaging (NBI) are both used to estimate the invasion depth of nonpedunculated rectal lesions (NPRLs). However, it is unclear which procedure is more accurate. This randomized controlled trial aimed to compare the diagnostic accuracy of linear EUS and NBI for estimating the invasion depth of NPRLs. METHODS: This study is a single-center, randomized, tandem trial. Eligible patients with NPRLs were randomly assigned to A group (assessment with EUS followed by NBI) or B group (assessment with NBI followed by EUS). The invasion depth of each lesion was independently measured by each procedure and categorized as mucosal to slight submucosal (M-SM s , invasion depth <1,000 µm) or deep submucosal (SM d , invasion depth ≥1,000 µm) invasion, with postoperative pathology as the standard of measurement. The primary outcome was diagnostic accuracy, and secondary outcomes included sensitivity, specificity, and procedure time. RESULTS: Eighty-six patients with NPRLs were enrolled, and 79 patients were finally analyzed, including 39 cases in the A group and 40 cases in the B group. Comparable diagnostic accuracies were observed between EUS and NBI (96.2% vs 93.7%, P = 0.625). EUS identified lesions with deep submucosal invasion with 81.8% sensitivity while that of NBI was 63.6% ( P = 0.500). The specificity of both EUS and NBI was 98.5%. The procedure time was also similar between EUS and NBI (5.90 ± 3.44 vs 6.4 ± 3.94 minutes, P = 0.450). Furthermore, the combined use of EUS and NBI did not improve diagnostic accuracy compared with EUS or NBI alone (94.9% vs 96.2% vs 93.7%, P = 0.333). DISCUSSION: Linear EUS and NBI measure the invasion depth of NPRLs with comparable accuracy. The combination of the 2 methods does not improve the diagnostic accuracy. Single NBI should be preferred, considering its simplicity and convenience in clinical practice.

Establishment of Early Blood Perfusion Promotes CXCL12 Expression and Recruits Monocytes/Macrophages in Damaged Adipose Tissue in Mice Model.

BACKGROUND: Blood perfusion in the recipient site is important for adipose tissue repair after fat grafting. It delivers host-derived macrophages derived from monocytes in bone marrow to initiate inflammatory reactions and regenerative responses. According to the ability of CXCL12, a stromal cell-derived factor, to recruit monocytes/macrophages, we studied its effect on adipose tissue repair and regeneration under ischemic and normal conditions. METHODS: Each inguinal fat pad was crushed for 30 seconds with a clamp in mice (n = 35). The left inguinal vessels were divided and cut off (ischemic group), while the right inguinal vessels were kept patent (control group). Seven animals were sacrificed at 1, 3, 7, 14, and 30 days after surgery, and macrophages (Mac2 and CD206) and adipocytes (perilipin) were assessed. Levels of inflammatory factors (interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α) and CXCL12 were measured by quantitative PCR. RESULTS: The number of macrophages was higher in the control group than in the ischemic group at day 3 (10.33 ± 2.40 vs. 1.33 ± 0.33, p = 0.021). The percentage of M2 macrophages was higher in the control group than in the ischemic group at day 7 (p<0.05). The levels of inflammatory factors and CXCL12 were higher in the control group than in the ischemic group at the early stage (p = 0.038). CONCLUSIONS: Established blood perfusion leads to up-regulation of CXCL12 during adipose tissue repair and regeneration, which may increase recruitment of monocytes to damaged adipose tissue. These findings increase understanding of the cellular events involved in fat graft survival after grafting. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Modified Cap-Assisted Endoscopic Mucosal Resection Versus Endoscopic Submucosal Dissection for the Treatment of Rectal Neuroendocrine Tumors ≤10 mm: A Randomized Noninferiority Trial.

INTRODUCTION: Although recent guidelines recommend endoscopic resection of rectal neuroendocrine tumors (NET) ≤10 mm, there is no consensus on which endoscopic modality should be performed. We aimed to compare the safety and efficacy of modified cap-assisted endoscopic mucosal resection (mEMR-C) and endoscopic submucosal dissection (ESD) methods for the treatment of rectal NET ≤10 mm. METHODS: A randomized noninferiority trial comparing mEMR-C and ESD was conducted. The primary outcome was the histological complete resection rate; the secondary outcomes included en bloc resection rate, operation time, complications, and so on. Subgroup analyses and follow-up were also performed. RESULTS: Ninety patients were enrolled, and 79 patients with pathologically confirmed rectal NET were finally analyzed, including 38 cases of mEMR-C and 41 cases of ESD. Histological complete resection rate was 97.4% in the mEMR-C group and 92.7% in the ESD group. The noninferiority of mEMR-C compared with that of ESD was confirmed because the absolute difference was 4.7% (2-sided 90% confidence interval, -3.3% to 12.2%; P = 0.616). En bloc resection and successful removal of rectal NET were achieved in all patients. Advantages of mEMR-C over ESD included shorter operation time (8.89 ± 4.58 vs 24.8 ± 9.14 minutes, P < 0.05) and lower hospitalization cost ($2,233.76 ± $717.70 vs $2,987.27 ± $871.81, P < 0.05). Postoperative complications were recorded in 4 patients who received mEMR-C and 2 patients in the ESD group (11.5% vs 4.9%, P = 0.509), which were all well managed using endoscopy. Similar findings were observed when subgroup analysis was performed. DISCUSSION: mEMR-C is noninferior to ESD with a similar complete resection rate. In addition, mEMR-C had shorter procedure duration time and lower hospitalization costs. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03982264.

Safety and effectiveness of mucosal traction using a snare combined with endoclips to assist the resection of esophageal intraepithelial neoplasia: a propensity score matching analysis.

Currently, the reports on esophageal endoscopic submucosal dissection (ESD) assisted by traction with a snare are rare. Because a snare is a commonly used endoscopic accessory and is easily available, its application in mucosal traction is worth exploring. The present study aims to evaluate the safety and effectiveness of snare-endoclip traction-assisted ESD for esophageal intraepithelial neoplasia. Cases of esophageal intraepithelial neoplasia resected using ESD in the Digestive Endoscopy Center of Guangzhou Nanfang Hospital, China from June 2013 to March 2019 were retrospectively analyzed. The procedure of snare-endoclip traction-assisted ESD was compared with nontraction-assisted ESD by using a propensity score matching analysis. Operation time, en bloc and R0 resection, intra- and postoperative complications, and surgery-related costs were mainly evaluated. Overall, 99 cases of esophageal intraepithelial neoplasia under tissue biopsy were included in the present study. Further, 22 exact matched pairs were obtained. There were no differences in en bloc and R0 resection rates, intra- and postoperative complications, and costs of disposable surgical accessories between the traction group and the nontraction group. However, median operation time showed a significant difference: traction group, 50.0 min (range, 20-100 min); nontraction group, 70.0 min (range, 35-133 min), P=0.012. In conclusion, snare-endoclip traction-assisted ESD for esophageal intraepithelial neoplasia was safe and shortened operation time in the study, thereby improving the efficiency of ESD. Despite the additional use of a snare and endoclips for traction, the total costs of endoscopic accessories seemed not to be increased.

Artificial intelligence-enhanced white-light colonoscopy with attention guidance predicts colorectal cancer invasion depth.

BACKGROUND AND AIMS: Endoscopic submucosal dissection (ESD) and EMR are applied in treating superficial colorectal neoplasms but are contraindicated by deeply invasive colorectal cancer (CRC). The invasion depth of neoplasms can be examined by an automated artificial intelligence (AI) system to determine the applicability of ESD and EMR. METHODS: A deep convolutional neural network with a tumor localization branch to guide invasion depth classification was constructed on the GoogLeNet architecture. The model was trained using 7734 nonmagnified white-light colonoscopy (WLC) images supplemented by image augmentation from 657 lesions labeled with histopathologic analysis of invasion depth. An independent testing dataset consisting of 1634 WLC images from 156 lesions was used to validate the model. RESULTS: For predicting noninvasive and superficially invasive neoplasms, the model achieved an overall accuracy of 91.1% (95% confidence interval [CI], 89.6%-92.4%), with 91.2% sensitivity (95% CI, 88.8%-93.3%) and 91.0% specificity (95% CI, 89.0%-92.7%) at an optimal cutoff of .41 and the area under the receiver operating characteristic (AUROC) curve of .970 (95% CI, .962-.978). Inclusion of the advanced CRC data significantly increased the sensitivity in differentiating superficial neoplasms from deeply invasive early CRC to 65.3% (95% CI, 61.9%-68.8%) with an AUROC curve of .729 (95% CI, .699-.759), similar to experienced endoscopists (.691; 95% CI, .624-.758). CONCLUSIONS: We have developed an AI-enhanced attention-guided WLC system that differentiates noninvasive or superficially submucosal invasive neoplasms from deeply invasive CRC with high accuracy, sensitivity, and specificity.

Standing-type magnetically guided capsule endoscopy versus gastroscopy for gastric examination: multicenter blinded comparative trial.

AIM: To compare feasibility and safety after gastrointestinal checkup by standing-type magnetically controlled capsule endoscopy (SMCE) and conventional gastroscopy. METHODS: This was a prospective multicenter, blinded study that compared SMCE with gastroscopy in patients from April 2018 to July 2018. All patients first underwent SMCE and then subsequently had gastroscopy with i.v. anesthesia. We calculated the compliance rates of gastric lesion detection by SMCE using gastroscopy as the standard. Capsule retention rate, incidence of adverse events, and patient satisfaction were documented throughout the study. RESULTS: One hundred and sixty-one patients who completed SMCE and gastroscopy were included in the analysis. Positive compliance rate among SMCE and gastroscopy was 92.0% (95% CI: 80.77%-97.78%). Negative compliance rate was 95.5% (89.80%, 98.52%). Moreover, overall compliance rate was 94.41% (89.65%, 97.41%). Sixty-four pathological outcomes were identified. Of these 64 outcomes, 50 were detected by both procedures. The gastroscopy method neglected seven findings (such as five erosions, one polyp, and one ulcer). Furthermore, SMCE also overlooked seven lesions (i.e. one erosion, two polyps, one atrophy, and three submucosal tumors). Capsule retention or related adverse events were not reported. CONCLUSION: Standing-type magnetically controlled capsule endoscopy provides equivalent agreement with gastroscopy and may be useful for screening of gastric illnesses without any anesthesia.

Snare combined with endoclips in endoscopic submucosal dissection with mucosal traction for gastroesophageal neoplasia.

BACKGROUND AND AIM: Mucosal traction as a "second hand" in endoscopic submucosal dissection (ESD) is very helpful for ESD operators. The efficacy of using a snare combined with endoclips to assist in ESD (SC-ESD) was evaluated whether it could achieve peroral external traction (PET) and peroral internal traction (PIT) and real-time adjustment of mucosal traction position. This study aimed to preliminarily evaluate its feasibility. METHODS: A snare was fixed using endoclips to the incised mucosal flap that was intended for dissection. Subsequently, the snare was adjusted to achieve mucosal traction. This study included 54 gastroesophageal neoplasias in 54 consecutive patients who underwent SC-ESD. The operative and clinical data were retrospectively collected. RESULTS: Peroral external tractions were performed for 22 esophageal neoplasias, and PETs and PITs were performed for 32 gastric neoplasias. The median (interquartile range) sizes of lesions were 4.3 (2.5) and 4.2 (2.1) cm, operation times were 73.4 (43.8) and 60.0 (45.2) min, and submucosal dissection times were 27.0 (32.0) and 31.0 (34.5) min in the esophagus and stomach, respectively. Mucosal traction position could be effectively adjusted by fixing the snare to the incised mucosal flap intended for dissection during SC-ESD. All lesions in the esophagus and stomach were completely resected, with R0 resection rates of 100%. Besides postoperative bleeding in a patient with gastric neoplasia, no intraoperative and postoperative perforations occurred. CONCLUSIONS: SC-ESD seems to be feasible for resecting gastroesophageal neoplasia, and two types of mucosal tractions (PET and PIT) could be effectively achieved during SC-ESD. Further prospective comparative study with a large sample is warranted.

Endoscopic mucosa-sparing lateral dissection for treatment of gastric submucosal tumors: a prospective cohort study.

BACKGROUND: In our previous work, we developed a modified method for the removal of gastric submucosal tumors (SMTs), called endoscopic mucosa-sparing lateral dissection (EMSLD). This prospective study aimed to evaluate the efficacy and postoperative outcomes of EMSLD. METHODS: We prospectively enrolled 25 consecutive patients with gastric SMTs, who received EMSLD treatment. Clinicopathological characteristics and operation-related outcomes were analyzed. RESULTS: The mean age of patients was 49.3 ±â€Š9.7 years, and the mean tumor size was 14.6 ±â€Š6.1 mm. En bloc resection was achieved in all cases. The mean procedure time was 47.3 ± 25.9 minutes, and the estimated blood loss was 4.8 ±â€Š3.5 mL. Endoscopic full-thickness resection was performed in six patients (24 %) because the tumors originated from the deep muscularis propria layer. All perforations and resection defects were successfully closed by the retained mucosa and endoclips. No serious complications related to EMSLD were encountered during or after the procedure. CONCLUSIONS: EMSLD was reliable and effective for the removal of gastric SMTs. However, large-scale randomized controlled trials are needed.

Comparison of endoscopic submucosal tunneling dissection and thoracoscopic enucleation for the treatment of esophageal submucosal tumors.

BACKGROUND AND AIMS: Endoscopic submucosal tunneling dissection (ESTD) has been proved to be safe and effective for removal of esophageal submucosal tumors (SMTs) and can maintain the mucosal integrity compared with other endoscopic methods. The aim of the study was to estimate the safety and efficacy of ESTD as well as compare its efficacy with thoracoscopic enucleation for esophageal SMTs, which is used increasingly as a minimally invasive approach. METHODS: We retrospectively collected the clinical data of patients with esophageal SMTs <40 mm who underwent ESTD or thoracoscopic enucleation at Nanfang Hospital between January 2008 and August 2016. Epidemiologic data (sex, age), tumor location, tumor size, en bloc resection rate, adverse events, pathologic results, length of postoperative hospital stay, and cost were compared between ESTD and thoracoscopic enucleation. RESULTS: A total of 126 patients were included. A total of 74 patients underwent ESTD, and the other 52 underwent thoracoscopic enucleation. There was no significant difference between the 2 groups in sex, age, tumor size, hospitalization expense, infection, adverse events, and en bloc resection rate (P < .05). However, patients in the ESTD group had a shorter operating time, less estimated blood loss, shorter length of postoperative hospital stay, and lower chest pain level (P < .05). Kaplan-Meier curves for disease-free survival also showed no statistically significant difference between ESTD and thoracoscopic enucleation groups during the median follow-up of 19.5 and 42 months, respectively. CONCLUSIONS: The treatment efficacy was comparable between the ESTD and thoracoscopic enucleation for esophageal SMTs <40 mm. However, there was a significant advantage in the ESTD group for a shorter operating time, reduced postoperative chest pain, and shorter hospitalization.

Modified submucosal tunneling endoscopic resection for submucosal tumors in the esophagus and gastric fundus near the cardia.

Background and study aims Submucosal tunneling endoscopic resection with double opening (DO-STER) was developed by our group for the resection of submucosal tumors in the esophagus and gastric fundus near the cardia. This study aimed to provide a preliminary evaluation of feasibility and safety of DO-STER. Methods The key to DO-STER is the creation of a tunnel opening in the mucosa over the inferior border of the tumor. During resection, the tumor can be gradually pushed out of the submucosal tunnel through the opening, leaving enough space for operation within the tunnel. A total of 10 tumors resected by DO-STER were retrospectively reviewed. Results All tumors were successfully resected by DO-STER. One tumor was located at the lower esophagus, four at the esophagogastric junction, and five at the gastric fundus near the cardia. Tumor size ranged from 1.0 × 1.2 cm to 3.5 × 5.0 cm, and all tumors originated from the muscularis propria. Operative times ranged from 45 to 150 minutes. No delayed bleeding or perforation occurred. Conclusion DO-STER seems to provide an alternative approach for resection of tumors in the esophagus and gastric fundus near the cardia.

Long-term outcomes of endoscopic submucosal dissection versus laparoscopic resection for gastric stromal tumors less than 2 cm.

BACKGROUND AND AIM: Laparoscopic resection (LAP) and endoscopic submucosal dissection (ESD) of small gastrointestinal stromal tumors (GISTs) have been reported by large amount of literature. However, the management of small GISTs remains controversial. This study evaluated the efficacy of ESD and LAP for small gastric GISTs and provided long-term outcomes of the two methods. METHODS: A total of 126 patients who underwent ESD or LAP for small gastric GISTs between 2009 and 2016 were retrospectively collected from medical records in our hospital, and we made telephone follow-up about recurrence rate. The parameters measured for each procedure type include clinicopathological characteristics, recurrence rate, and surgical outcomes. RESULTS: Among the 126 patients, 75 (59.52%) received ESD, and 51(40.48%) received LAP. The clinicopathological characteristics of the patients were well balanced. There was also no significant difference in follow-up time (3.34 ± 1.53 years in ESD group and 3.41 ± 1.37 years in LAP group, P = 0.19). However, we observed significant difference about operating time, estimated blood loss, and hospital stay between ESD group and LAP group (63.59 ± 34.41 min vs 79.12 ± 43.47 min, P = 0.04; 8.53 ± 15.89 mL vs 17.16 ± 18.90 mL, P = 0.01; 6.60 ± 2.70 days vs 10.37 ± 3.50 days, P < 0.001, respectively). The recurrence rate of ESD and LAP group was 2.67% and 1.96%, respectively, P = 0.41. Kaplan-Meier curves for disease-free survival also showed no statistically significant difference (P = 0.72). CONCLUSIONS: Endoscopic submucosal dissection is a preferable technique for resection of small gastric stromal tumors in the long-term outcomes compared with LAP. However, long-term randomized controlled trials are further needed.

Role of transgastric natural orifice transluminal endoscopic surgery in the diagnosis of ascites of unknown origin (with videos).

BACKGROUND: Natural orifice transluminal endoscopic surgery (NOTES) has been established in animal models and human studies. OBJECTIVE: The aim of this study was to assess the feasibility and efficacy of applying transgastric NOTES to diagnose patients with ascites of unknown origin. DESIGN: Prospective study. SETTING: Two university and teaching hospitals. PATIENTS: Patients with ascites of unknown origin. INTERVENTIONS: Diagnostic transgastric NOTES. MAIN OUTCOME MEASUREMENTS: Characteristic of ascites cases, conditions of the abdominal cavity, diagnostic accuracy, adverse events, and follow-up time. RESULTS: Transgastric NOTES was performed successfully in 78 patients with ascites of unknown origin, and 72 cases (92.3%) were clearly diagnosed. They included malignant tumors (39 cases), tuberculous peritonitis (28 cases), chronic hepatic inflammation (3 cases), necrotizing lymphadenitis (1 case), and eosinophilic serositis of the small intestine (1 case). In addition, there were 6 nondiagnostic cases, and no severe adverse events were found. LIMITATIONS: Nonrandomized control analysis. CONCLUSION: Transgastric NOTES in combination with biopsy can elucidate the causes of ascites of unknown origin in the majority of cases. Therefore, it is a feasible and effective approach to access the peritoneal cavity and also a valuable modality to detect the cause of diseases with ascites of unknown origin.

METTL14-dependent maturation of pri-miR-17 regulates mitochondrial homeostasis and induces chemoresistance in colorectal cancer.

miR-17-5p has been found to be involved in the proliferation and metastasis of colorectal cancer (CRC), and N6-methyladenosine (m6A) modification is the most common RNA modification in eukaryotes. However, whether miR-17-5p contributes to chemotherapy sensitivity in CRC via m6A modification is unclear. In this study, we found that overexpression of miR-17-5p led to less apoptosis and lower drug sensitivity in vitro and in vivo under the 5-fluorouracil (5-FU) treatment, which indicated miR-17-5p led to 5-FU chemotherapy resistance. Bioinformatic analysis suggested that miR-17-5p-mediated chemoresistance was associated with mitochondrial homeostasis. miR-17-5p directly bound to the 3' untranslated region of Mitofusin 2 (MFN2), leading to decreased mitochondrial fusion and enhanced mitochondrial fission and mitophagy. Meanwhile, methyltransferase-like protein 14 (METTL14) was downregulated in CRC, resulting in lower m6A level. Moreover, the low level of METTL14 promoted the expression of pri-miR-17 and miR-17-5p. Further experiments suggested that m6A mRNA methylation initiated by METTL14 inhibits pri-miR-17 mRNA decay via reducing the recognition of YTHDC2 to the "GGACC" binding site. The METTL14/miR-17-5p/MFN2 signaling axis may play a critical role in 5-FU chemoresistance in CRC.

Usefulness of tumor traction with a snare and endoclips in gastric submucosal tumor resection: a propensity-score-matching analysis.

BACKGROUND: Endoscopic resection, including endoscopic submucosal dissection (ESD) and endoscopic full-thickness resection (EFR), was used to resect small gastric submucosal tumors (SMTs). Our team explored a method of tumor traction using a snare combined with endoclips to assist in the resection of SMTs. This study aims to explore the safety and effectiveness of the method. METHODS: This research performed a propensity-score-matching (PSM) analysis to compare ESD/EFR assisted by a snare combined with endoclips (ESD/EFR with snare traction) with conventional ESD/EFR for the resection of gastric SMTs. Comparisons were made between the two groups, including operative time, en bloc resection rate, perioperative complications, and operation-related costs. RESULTS: A total of 253 patients with gastric SMTs resected between January 2012 and March 2019 were included in this study. PSM yielded 51 matched pairs. No significant differences were identified between the two groups in perioperative complications or the costs of disposable endoscopic surgical accessories. However, the ESD/EFR-with-snare-traction group had a shorter median operative time (39 vs 60 min, P = 0.005) and lower rate of en bloc resection (88.2% vs 100%, P = 0.027). CONCLUSIONS: ESD/EFR with snare traction demonstrated a higher efficiency and en bloc resection rate for gastric SMTs, with no increases in perioperative complications and the costs of endoscopic surgical accessories. Therefore, the method seems an appropriate choice for the resection of gastric SMTs.

VDR Signaling via the Enzyme NAT2 Inhibits Colorectal Cancer Progression.

Recent epidemiological and preclinical evidence indicates that vitamin D3 inhibits colorectal cancer (CRC) progression, but the mechanism has not been completely elucidated. This study was designed to determine the protective effects of vitamin D3 and identify crucial targets and regulatory mechanisms in CRC. First, we confirmed that 1,25(OH)2D3, the active form of vitamin D3, suppressed the aggressive phenotype of CRC in vitro and in vivo. Based on a network pharmacological analysis, N-acetyltransferase 2 (NAT2) was identified as a potential target of vitamin D3 against CRC. Clinical data of CRC patients from our hospital and bioinformatics analysis by online databases indicated that NAT2 was downregulated in CRC specimens and that the lower expression of NAT2 was correlated with a higher metastasis risk and lower survival rate of CRC patients. Furthermore, we found that NAT2 suppressed the proliferation and migration capacity of CRC cells, and the JAK1/STAT3 signaling pathway might be the underlying mechanism. Moreover, Western blot and immunofluorescence staining assays demonstrated that 1,25(OH)2D3 promoted NAT2 expression, and the chromatin immunoprecipitation assay indicated that the vitamin D receptor (VDR) transcriptionally regulated NAT2. These findings expand the potential uses of vitamin D3 against CRC and introduce VDR signaling via the enzyme NAT2 as a potential diagnostic and therapeutic target for CRC.

Cancer-associated fibroblasts-derived exosomal miR-17-5p promotes colorectal cancer aggressive phenotype by initiating a RUNX3/MYC/TGF-ß1 positive feedback loop.

Cancer-associated fibroblasts (CAFs) are the main stromal cells in the tumour microenvironment (TME). We found that the distribution of CAFs was significantly increased with tumour progression and led to a poor prognosis. In vitro and in vivo assays revealed that CAFs enhanced colorectal cancer (CRC) metastasis. Based on extraction and identification of exosomes of CAFs and normal fibroblasts (NFs), CAFs-exo showed higher expression of miR-17-5p than NFs-exo and could deliver exosomal miR-17-5p from parental CAFs to CRC cells. Further exploration verified that miR-17-5p influenced CRC metastasis capacity and directly targeted 3'-untranslated regions (UTRs) of RUNX family transcription factor 3(RUNX3). Our findings further revealed that RUNX3 interacted with MYC proto-oncogene(MYC) and that both RUNX3 and MYC bound to the promoter of transforming growth factor beta1(TGF-ß1) at base pairs 1005-1296, thereby activating the TGF-ß signalling pathway and contributing to tumour progression. In addition, RUNX3/MYC/TGF-ß1 signalling sustained autocrine TGF-ß1 to activate CAFs, and activated CAFs released more exosomal miR-17-5p to CRC cells, forming a positive feedback loop for CRC progression. Taken together, these data provide a new understanding of the potential diagnostic value of exosomal miR-17-5p in CRC.

CTCF promotes colorectal cancer cell proliferation and chemotherapy resistance to 5-FU via the P53-Hedgehog axis.

CTCF is overexpressed in several cancers and plays crucial roles in regulating aggressiveness, but little is known about whether CTCF drives colorectal cancer progression. Here, we identified a tumor-promoting role for CTCF in colorectal cancer. Our study demonstrated that CTCF was upregulated in colorectal cancer specimens compared with adjacent noncancerous colorectal tissues. The overexpression of CTCF promoted colorectal cancer cell proliferation and tumor growth, while the opposite effects were observed in CTCF knockdown cells. Increased GLI1, Shh, PTCH1, and PTCH2 levels were observed in CTCF-overexpressing cells using western blot analyses. CCK-8 and apoptosis assays revealed that 5-fluorouracil chemosensitivity was negatively associated with CTCF expression. Furthermore, we identified that P53 is a direct transcriptional target gene of CTCF in colorectal cancer. Western blot and nuclear extract assays showed that inhibition of P53 can counteract Hedgehog signaling pathway repression induced by CTCF knockdown. In conclusion, we uncovered a crucial role for CTCF regulation that possibly involves the P53-Hedgehog axis and highlighted the clinical utility of colorectal cancer-specific potential therapeutic target as disease progression or clinical response biomarkers.