Mitochondrial DNA Copy Number as a Biomarker for Guiding Adjuvant Chemotherapy in Stages II and III Colorectal Cancer Patients with Mismatch Repair Deficiency: Seeking Benefits and Avoiding Harms.

BACKGROUND: Colorectal cancer (CRC) patients with mismatch repair-deficient/microsatellite instability-high (dMMR/MSI-H) status are conventionally perceived as unresponsive to adjuvant chemotherapy (ACT). The mitochondrial transcription factor A (TFAM) is required for mitochondrial DNA copy number (mtDNA-CN) expression. In light of previous findings indicating that the frequent truncating-mutation of TFAM affects the chemotherapy resistance of MSI CRC cells, this study aimed to explore the potential of mtDNA-CN as a predictive biomarker for ACT efficacy in dMMR CRC patients. METHODS: Levels of MtDNA-CN were assessed using quantitative real-time polymerase chain reaction (qRT-PCR) in a cohort of 308 CRC patients with dMMR comprising 180 stage II and 128 stage III patients. Clinicopathologic and therapeutic data were collected. The study examined the association between mtDNA-CN levels and prognosis, as well as the impact of ACT benefit on dMMR CRC patients. Subgroup analyses were performed based mainly on tumor stage and mtDNA-CN level. Kaplan-Meier and Cox regression models were used to evaluate the effect of mtDNA-CN on disease-free survival (DFS) and overall survival (OS). RESULTS: A substantial reduction in mtDNA-CN expression was observed in tumor tissue, and higher mtDNA-CN levels were correlated with improved DFS (73.4% vs 85.7%; P = 0.0055) and OS (82.5% vs 90.3%; P = 0.0366) in dMMR CRC patients. Cox regression analysis identified high mtDNA-CN as an independent protective factor for DFS (hazard ratio [HR] 0.547; 95% confidence interval [CI] 0.321-0.934; P = 0.0270) and OS (HR 0.520; 95% CI 0.272-0.998; P = 0.0492). Notably, for dMMR CRC patients with elevated mtDNA-CN, ACT significantly improved DFS (74.6% vs 93.4%; P = 0.0015) and OS (81.0% vs 96.7%; P = 0.0017), including those with stage II or III disease. CONCLUSIONS: The mtDNA-CN levels exhibited a correlation with the prognosis of stage II or III CRC patients with dMMR. Elevated mtDNA-CN emerges as a robust prognostic factor, indicating improved ACT outcomes for stages II and III CRC patients with dMMR. These findings suggest the potential utility of mtDNA-CN as a biomarker for guiding personalized ACT treatment in this population.

Tumor-associated microbiota in colorectal cancer with vascular tumor thrombus and neural invasion and association with clinical prognosis.

Neural invasion (NI) and vascular tumor thrombus (VT) are associated with poor prognosis in patients with colorectal cancer (CRC). In this study, we apply 16S rRNA amplicon sequencing to tumor tissues and adjacent normal tissues in patients with CRC to determine the microbial differences. A discovery cohort, including 30 patients with NI, 23 with VT, and 35 with double-negative CRC tissue, is utilized. Then, we analyze the relationship between the specific bacterial taxa and indicators of different dimensions in separate cohorts. In the discovery cohort, the diversity and composition of the gut microbiome distinctly differ between the tumor and nontumor tissues in the NI and VT groups. A high abundance of Cupriavidus is found to be related to a short survival time of NI CRC, while Herbaspirillum is a potential microbial biomarker predicting the prognosis of patients with CRC with NI or VT. Moreover, the abundance of Cupriavidus or Herbaspirillum is associated with some clinical patient characteristics and prognosis, respectively. In conclusion, this study is the first to comprehensively elaborate the differences in the gut microbiota of patients with CRC with different invasion statuses and to prove the relationship between some gut microbiota and clinical patient characteristics.

Metabolic stress-induced reciprocal loop of long noncoding RNA ZFAS1 and ZEB1 promotes epithelial-mesenchymal transition and metastasis of pancreatic cancer cells.

Pancreatic cancer (PC) development faces significant metabolic stress due to metabolic reprogramming and a distinct hypovascular nature, often leading to glucose and glutamine depletion. However, the adaption mechanisms by which PC adapts to these metabolic challenges have not yet been completely explored. Here, we found that metabolic stress induced by glucose and glutamine deprivation led to an overexpression of ZNFX1 antisense RNA 1 (ZFAS1). This overexpression played a significant role in instigating PC cell epithelial-mesenchymal transition (EMT) and metastasis. Mechanistically, ZFAS1 enhanced the interaction between AMPK, a key kinase, and ZEB1, the primary regulator of EMT. This interaction resulted in the phosphorylation and subsequent stabilization of ZEB1. Interestingly, ZEB1 also reciprocally influenced the transcription of ZFAS1 by binding to its promoter. Furthermore, when ZFAS1 was depleted, the nutrient deprivation-induced EMT of PC cells and lung metastasis in nude mice were significantly inhibited. Our investigations also revealed that ZFAS1-rich exosomes released from cells suffering glucose and glutamine deprivation promoted the EMT and metastasis of recipient PC cells. Corroborating these findings, a correlated upregulation of ZFAS1 and ZEB1 expression was observed in PC tissues and was associated with a poor overall survival rate for patients. Our findings highlight the involvement of a long noncoding RNA-driven metabolic adaptation in promoting EMT and metastasis of PC, suggesting ZFAS1 as a promising novel therapeutic target for PC metabolic treatment.

Perineural invasion affects prognosis of patients undergoing colorectal cancer surgery: a propensity score matching analysis.

BACKGROUND: Tumour perineural invasion (PNI) is a predictor of poor prognosis, but its effect on the prognosis of patients with colorectal cancer (CRC) has not yet been elucidated. METHODS: This retrospective study used propensity score matching (PSM). The clinical case data of 1470 patients with surgically treated stage I-IV CRC at Wuhan Union Hospital were collected. PSM was used to analyse and compare the clinicopathological characteristics, perioperative outcomes, and long-term prognostic outcomes of the PNI(+) and PNI(-) groups. The factors influencing prognosis were screened using Cox univariate and multivariate analyses. RESULTS: After PSM, 548 patients were included in the study (n = 274 in each group). Multifactorial analysis showed that neurological invasion was an independent prognostic factor affecting patients' OS and DFS (hazard ratio [HR], 1.881; 95% confidence interval [CI], 1.35-2.62; P = 0.0001; HR, 1.809; 95% CI, 1.353-2.419; P < 0.001). Compared to PNI(+) patients without chemotherapy, those who received chemotherapy had a significant improvement in OS (P < 0.01). The AUROC curve of OS in the PNI(+) subgroup (0.802) was higher than that after PSM (0.743), while that of DFS in the PNI(+) subgroup (0.746) was higher than that after PSM (0.706). The independent predictors of PNI(+) could better predict the prognosis and survival of patients with PNI(+). CONCLUSIONS: PNI significantly affects the long-term survival and prognosis of patients with CRC undergoing surgery and is an independent risk factor for OS and DFS in patients with CRC undergoing surgery. Postoperative chemotherapy significantly improved the OS of PNI(+) patients.

Modified Naples prognostic score for evaluating the prognosis of patients with obstructive colorectal cancer.

BACKGROUND: Inflammatory, immune, and nutritional status are key factors in obstructive colorectal cancer (OCRC). This study aims to investigate the value of modified Naples prognostic score (M-NPS) in evaluating OCRC prognosis. METHODS: A total of 196 OCRC patients were retrospectively analyzed to construct M-NPS based on serum albumin (ALB), total cholesterol (CHOL), neutrophil:lymphocyte ratio (NLR), and lymphocyte:monocyte ratio (LMR), and then they were divided into three groups. The Kaplan-Meier (KM) method and Cox proportional hazard regression analysis were performed for overall survival (OS) and disease-free survival (DFS) of OCRC patients. RESULTS: Patients with high M-NPS had worse OS and DFS (P = 0.0001, P = 0.0011). Multivariate COX analysis showed that M-NPS was an independent prognostic factor for OCRC patients. Patients in the M-NPS 2 group had significantly worse OS (hazard ratio [HR] = 4.930 (95% confidence interval [95% CI], 2.217-10.964), P < 0.001) and DFS (HR = 3.508 (95% CI, 1.691-7.277), P < 0.001) than those in the 0 group. CONCLUSION: M-NPS was an independent prognostic factor for OCRC patients; it might provide a potential reference for immunonutritional intervention in patients with obstruction.

Endoscopic fully covered self-expandable metal stent and vacuum-assisted drainage to treat postoperative colorectal cancer anastomotic stenosis with fistula.

BACKGROUND: Digestive tract reconstruction is required after the surgical resection of a colorectal malignant tumor. Some patients may have concomitant anastomotic complications, such as anastomotic stenosis with fistula (ASF), postoperatively. Therefore, we evaluated the efficacy and safety of endoscopic fully covered self-expandable metal stent and homemade vacuum sponge-assisted drainage (FSEM-HVSD) for the treatment of ASF following the radical resection of colorectal cancer. METHODS: Patients treated with FESM-HVSD were prospectively analyzed and followed up for ASF following colorectal cancer treatment in our medical center from 2017 to 2021 for the observation and evaluation of its safety and efficacy. RESULTS: Fifteen patients with a mean age of 55.80 ± 11.08 years were included. Nine patients (60%) underwent protective ileostomy. All 15 patients were treated with endoscopic FSEM-HVSD. The median time from the index operation to the initiation of FSEM-HVSD was 80 ± 20.34 days in patients who underwent protective ileostomy versus 11.4 ± 4.4 days in those who did not. The average number of endoscopic treatments per patient was 5.70 ± 1.25 times. The mean length of hospital stay was 27.60 ± 4.43 days. FSEM-HVSD treatment was successful in 13 patients, and no patients had any complications. The follow-up time was 1 year. Twelve of 15 (80%) patients achieved prolonged clinical success after FSEM-HVSD treatment, 1 experienced anastomotic tumor recurrence and underwent surgery again, and 1 patient required balloon dilation for anastomotic stenosis recurrence. CONCLUSIONS: FSEM-HVSD is an effective, safe, and minimally invasive treatment for ASF following colorectal cancer treatment. This technique could be the preferred treatment strategy for patients with ASF.

Systematic Functional Interrogation of Genes in GWAS Loci Identified ATF1 as a Key Driver in Colorectal Cancer Modulated by a Promoter-Enhancer Interaction.

Genome-wide association studies (GWASs) have identified approximately 100 colorectal cancer (CRC) risk loci. However, the causal genes in these loci have not been systematically interrogated. We conducted a high-throughput RNA-interference functional screen to identify the genes essential for proliferation in the CRC risk loci of Asian populations. We found that ATF1, located in the 12q13.12 region, functions as an oncogene that facilitates cell proliferation; ATF1 has the most significant effect of the identified genes and promotes CRC xenograft growth by affecting cell apoptosis. Next, by integrating a fine-mapping analysis, a two-stage affected-control study consisting of 6,213 affected individuals and 10,388 controls, and multipronged experiments, we elucidated that two risk variants, dbSNP: rs61926301 and dbSNP: rs7959129, that located in the ATF1 promoter and first intron, respectively, facilitate a promoter-enhancer interaction, mediated by the synergy of SP1 and GATA3, to upregulate ATF1 expression, thus synergistically predisposing to CRC risk (OR = 1.77, 95% CI = 1.42-2.21, p = 3.16 × 10-7; Pmultiplicative-interaction = 1.20 × 10-22; Padditive-interaction = 6.50 × 10-3). Finally, we performed RNA-seq and ChIP-seq assays in CRC cells treated with ATF1 overexpression in order to dissect the target programs of ATF1. Results showed that ATF1 activates a subset of genes, including BRAF, NRAS, MYC, BIRC2, DAAM1, MAML2, STAT1, ID1, and NKD2, related to apoptosis, Wnt, TGF-ß, and MAPK pathways, and these effects could cooperatively increase the risk of CRC. These findings reveal the clinical potential of ATF1 in CRC development and illuminate a promoter-enhancer interaction module between the ATF1 regulatory elements dbSNP: rs61926301 and dbSNP: rs7959129, and they bring us closer to understanding the molecular drivers of cancer.

Development and validation of a prognostic scoring system for patients with colorectal cancer hepato-pulmonary metastasis: a retrospective study.

BACKGROUND: Hepato-pulmonary metastasis of colorectal cancer (CRC) is a rare disease with poor prognosis. This study aims to establish a highly efficient nomogram model to predict overall survival (OS) and cancer-specific survival (CSS) in patients with colorectal cancer hepato-pulmonary metastasis (CRCHPM). METHODS: We retrospectively analyzed the data of patients with CRCHPM from SEER database and Wuhan Union Hospital Cancer Center (WUHCC). A total of 1250 CRCHPM patients were randomly assigned to the training, internal validation, and external validation cohorts from 2010 to 2016.Univariate and multivariate cox analysis were performed to identify independent clinicopathological predictors of OS and CSS, and a nomogram was constructed to predict OS and CSS in CRCHPM patients. RESULTS: A nomogram of OS was constructed based on seven independent predictors of age, degree of differentiation, T stage, chemotherapy, number of lsampled lymph nodes, number of positive lymph nodes, and tumor size. Nomogram showed favorable sensitivity in predicting OS at 1, 3 and 5 years, with area under the receiver operating characteristic curve (AUROC) values of 0.802, 0.759 and 0.752 in the training cohort;0.814, 0.769 and 0.716 in the internal validation cohort;0.778, 0.756 and 0.753 in the external validation cohort, respectively. A nomogram of CSS was constructed based on three independent predictors of T stage, chemotherapy, and tumor size. The AUROC values of 1, 3 and 5 years were 0.709,0.588,0.686 in the training cohort; 0.751, 0.648,0.666 in the internal validation cohort;0.781,0.588,0.645 in the external validation cohort, respectively. Calibration curves, Concordance index (C-index), and decision curve analysis (DCA) results revealed that using our model to predict OS and CSS is more efficient than other single clinicopathological characteristics. CONCLUSION: A nomogram of OS and CSS based on clinicopathological characteristics can be conveniently used to predict the prognosis of CRCHPM patients.

Application of nanotechnology in the early diagnosis and comprehensive treatment of gastrointestinal cancer.

Gastrointestinal cancer (GIC) is a common malignant tumour of the digestive system that seriously threatens human health. Due to the unique organ structure of the gastrointestinal tract, endoscopic and MRI diagnoses of GIC in the clinic share the problem of low sensitivity. The ineffectiveness of drugs and high recurrence rates in surgical and drug therapies are the main factors that impact the curative effect in GIC patients. Therefore, there is an urgent need to improve diagnostic accuracies and treatment efficiencies. Nanotechnology is widely used in the diagnosis and treatment of GIC by virtue of its unique size advantages and extensive modifiability. In the diagnosis and treatment of clinical GIC, surface-enhanced Raman scattering (SERS) nanoparticles, electrochemical nanobiosensors and magnetic nanoparticles, intraoperative imaging nanoparticles, drug delivery systems and other multifunctional nanoparticles have successfully improved the diagnosis and treatment of GIC. It is important to further improve the coordinated development of nanotechnology and GIC diagnosis and treatment. Herein, starting from the clinical diagnosis and treatment of GIC, this review summarizes which nanotechnologies have been applied in clinical diagnosis and treatment of GIC in recent years, and which cannot be applied in clinical practice. We also point out which challenges must be overcome by nanotechnology in the development of the clinical diagnosis and treatment of GIC and discuss how to quickly and safely combine the latest nanotechnology developed in the laboratory with clinical applications. Finally, we hope that this review can provide valuable reference information for researchers who are conducting cross-research on GIC and nanotechnology.

A nomogram based on pretreatment levels of serum bilirubin and total bile acid levels predicts survival in colorectal cancer patients.

BACKGROUND: Serum bilirubin and total bile acid (TBA) levels have been reported to be strongly associated with the risk and prognosis of certain cancers. Here, we aimed to investigate the effects of pretreatment levels of serum bilirubin and bile acids on the prognosis of patients with colorectal cancer (CRC). METHODS: A retrospective cohort of 1474 patients with CRC who underwent surgical resection between January 2015 and December 2017 was included in the study. Survival analysis was used to evaluate the predictive value of pretreatment levels of bilirubin and bile acids. X-Tile software was used to identify optimal cut-off values for total bilirubin (TBIL), direct bilirubin (DBIL) and TBA in terms of overall survival (OS) and disease-free survival (DFS). RESULTS: DBIL, TBIL, and TBA were validated as significant prognostic factors by univariate Cox regression analysis for both 3-year OS and DFS. Multivariate Cox regression analyses confirmed that high DBIL, TBIL and TBA levels were independent prognostic factors for both OS (HR: 0.435, 95% CI: 0.299-0.637, P < 0.001; HR: 0.436, 95% CI: 0.329-0.578, P < 0.001; HR: 0.206, 95% CI: 0.124-0.341, P < 0.001, respectively) and DFS (HR: 0.583, 95% CI: 0.391-0.871, P = 0.008; HR:0.437,95% CI: 0.292-0.655, P <0.001; HR: 0.634, 95% CI: 0.465-0.865, P = 0.004, respectively). In addition, nomograms for OS and DFS were established according to all significant factors, and the c-indexes were 0.819 (95% CI: 0.806-0.832) and 0.835 (95% CI: 0.822-0.849), respectively. CONCLUSIONS: TBIL, DBIL and TBA levels are independent prognostic factors in colorectal cancer patients. The nomograms based on OS and DFS can be used as a practical model for evaluating the prognosis of CRC patients.

Application of endoscopic technique in completely occluded anastomosis with anastomotic separation after radical resection of colon cancer: a case report and literature review.

BACKGROUND: Anastomosis-related complications are common after the radical resection of colon cancer. Among such complications, severe stenosis or completely occluded anastomosis (COA) are uncommon in clinical practice, and the separation of the anastomosis is even rarer. For such difficult problems as COA or anastomotic separation, clinicians tend to adopt surgical interventions, and few clinicians try to solve them through endoscopic operations. CASE PRESENTATION: In this article, we present a case of endoscopic treatment of anastomotic closure and separation after radical resection for sigmoid carcinoma. After imaging examination and endoscopic evaluation, we found that the patient had a COA accompanied by a 3-4 cm anastomotic separation. With the aid of fluoroscopy, we attempted to use the titanium clip marker as a guide to perform an endoscopic incision and successfully achieved recanalization. We used a self-expanding covered metal stent to bridge the intestinal canal to resolve the anastomotic separation. Finally, the patient underwent ileostomy takedown, and the postoperative recovery was smooth. The follow-up evaluation results showed that the anastomotic stoma was unobstructed. CONCLUSIONS: We reported the successful application of endoscopic technique in a rare case of COA and separation after colon cancer surgery, which is worth exploring and verifying through more clinical studies in the future.

Long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 cooperates with enhancer of zeste homolog 2 to promote hepatocellular carcinoma development by modulating the microRNA-22/Snail family transcriptional repressor 1 axis.

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is an oncogenic long noncoding RNA that has been found to promote carcinogenesis and metastasis in many tumors. However, the underlying role of MALAT1 in the progression and metastasis of hepatocellular carcinoma (HCC) remains unclear. In this study, aberrantly elevated levels of MALAT1 were detected in both HCC specimens and cell lines. We found that knockdown of MALAT1 caused retardation in proliferation, migration, and invasion both in vivo and in vitro. Mechanistic investigations showed that Snail family transcriptional repressor 1 (SNAI1) is a direct target of microRNA (miR)-22 and that MALAT1 modulates SNAI1 expression by acting as a competing endogenous RNA for miR-22. Inhibition of miR-22 restored SNAI1 expression suppressed by MALAT1 knockdown. Furthermore, MALAT1 facilitated the enrichment of enhancer of zeste homolog 2 (EZH2) at the promoter region of miR-22 and E-cadherin, which was repressed by MALAT1 knockdown. Cooperating with EZH2, MALAT1 positively regulated SNAI1 by repressing miR-22 and inhibiting E-cadherin expression, playing a vital role in epithelial to mesenchymal transition. In conclusion, our results reveal a mechanism by which MALAT1 promotes HCC progression and provides a potential target for HCC therapy.

Imaging and clinical features of patients with 2019 novel coronavirus SARS-CoV-2: A systematic review and meta-analysis.

BACKGROUND: Currently, the epidemic of coronavirus disease 2019 (COVID-19) has begun to spread worldwide. We aim to explore reliable evidence for the diagnosis and treatment of the COVID-19 by analyzing all the published studies by Chinese scholars on the clinical and imaging features in novel coronavirus pneumonia caused by SARS-CoV-2. METHODS: We searched five medical databases including two Chinese and three English databases for all published articles on COVID-19 since the outbreak. A random-effects model was designed, and the imaging and clinical data from all studies were collected for meta-analysis. RESULTS: Overall, 31 articles and 46 959 patients were included, including 10 English articles and 21 Chinese articles. The results of meta-analysis showed that the most common clinical manifestations were fever (87.3%; 0.838-0.909), cough (58.1%; 0.502-0.660), dyspnea (38.3%; 0.246-0.520), muscle soreness or fatigue (35.5%; 0.253-0.456), and chest distress (31.2%; -0.024 to 0.648). The main imaging findings were bilateral pneumonia (75.7%; 0.639-0.871) and ground-glass opacification (69.9%; 0.602-0.796). Among the patients, the incidence that required intensive care unit (ICU) was (29.3%; 0.190-0.395), the incidence with acute respiratory distress syndrome was (28.8%; 0.147-0.429), the incidence with multiple organ dysfunction syndrome was (8.5%; -0.008 to 0.179), and the case fatality rate of patients with COVID-19 was (6.8%; 0.044-0.093). CONCLUSION: COVID-19 is a new clinical infectious disease that mainly causes bilateral pneumonia and lung function deteriorates rapidly. Nearly a third of patients need to be admitted to the ICU, and patients are likely to present respiratory failure or even death.

The value of haematological parameters and serum tumour markers for predicting KRAS mutations in 784 Chinese colorectal cancer patients: a retrospective analysis.

BACKGROUND: Identifying the mutation status of KRAS is important for optimizing treatment in patients with colorectal cancer (CRC). The aim of this study was to investigate the predictive value of haematological parameters and serum tumour markers (STMs) for KRAS gene mutations. METHODS: The clinical data of patients with colorectal cancer from January 2014 to December 2018 were retrospectively collected, and the associations between KRAS mutations and other indicators were analysed. Receiver operating characteristic (ROC) curve analysis was performed to quantify the predictive value of these factors. Univariate and multivariate logistic regression models were applied to identify predictors of KRAS mutations by calculating the odds ratios (ORs) and their corresponding 95% confidence intervals (CIs). RESULTS: KRAS mutations were identified in 276 patients (35.2%). ROC analysis revealed that age, CA12-5, AFP, SCC, CA72-4, CA15-3, FERR, CYFRA21-1, MCHC, and tumor location could not predict KRAS mutations (P = 0.154, 0.177, 0.277, 0.350, 0.864, 0.941, 0.066, 0.279, 0.293, and 0.053 respectively), although CEA, CA19-9, NSE and haematological parameter values showed significant predictive value (P = 0.001, < 0.001, 0.043 and P = 0.003, < 0.001, 0.001, 0.031, 0.030, 0.016, 0.015, 0.019, and 0.006, respectively) but without large areas under the curve. Multivariate logistic regression analysis showed that CA19-9 was significantly associated with KRAS mutations and was the only independent predictor of KRAS positivity (P = 0.016). CONCLUSIONS: Haematological parameters and STMs were related to KRAS mutation status, and CA19-9 was an independent predictive factor for KRAS gene mutations. The combination of these clinical factors can improve the ability to identify KRAS mutations in CRC patients.

Perineural invasion is associated with poor prognosis of colorectal cancer: a retrospective cohort study.

PURPOSE: Perineural invasion (PNI) is associated with poor prognosis in a variety of cancers. Our aim was to determine the clinicopathological factors associated with PNI in colorectal cancer (CRC) and its impact on patient survival. MATERIAL AND METHODS: The clinical data of 1412 patients diagnosed with CRC from July 2013 to July 2016 were retrospectively collected. PNI was determined based on hematoxylin-eosin staining. The relationships of PNI with various clinicopathological factors and prognosis were analyzed. RESULTS: The incidence of PNI in the entire cohort was 21.5%. PNI was significantly more common in patients with lower tumor differentiation, higher tumor stage, vascular invasion, TNM stage, tumor diameter, MMR/KRAS/NRAS/BRAF mutation, and more positive lymph nodes. Logistic regression analysis showed that T stage, vascular invasion, tumor diameter, and MMR were the main influencing factors of PNI. Cox regression analysis showed that poor tumor differentiation, N stage, TNM stage, PNI, and BRAF status were independent prognostic factors for OS. The OS, CSS, and PFS rate of the PNI (-) group was higher than that of the PNI (+) group, and the difference was statistically significant (P < 0.001). CONCLUSION: PNI in patients with colorectal cancer is significantly associated with T stage, TNM stage, vessel invasion, tumor diameter, MMR status, and BRAF mutation. PNI status is an independent prognostic factor for CRC. Assessing the postoperative PNI status may help predict prognosis and determine further treatment options for these patients.

Three functional variants were identified to affect RPS24 expression and significantly associated with risk of colorectal cancer.

GWAS-identified 10q22.3 loci with lead SNP rs704017 are significantly associated with CRC risk in both Asian and European populations. However, the functional mechanism of this region is unclear. In this study, we performed a fine-mapping analysis to identify the causal SNPs. To identify potential functional SNPs in linkage disequilibrium with the lead SNP, we searched for the potential target genes using a Hi-C database and an RNA interfering-based on-chip approach. The results indicated that rs12263636 (r2 = 0.41) showed the highest potential to be functional. It resided in a region with enhancer markers and a topologically associating domain. We found that RPS24 was the only gene that significantly promoted the proliferation rate of CRC cells and might have promoter-enhancer interaction with rs12263636. Dual-luciferase reporter assays confirmed that the risk alleles of two variants (rs3740253 and rs7071351) in RPS24 promoter could increase the expression of luciferase. Case control study consisting of 1134 cases and 2039 health controls confirmed that both the two variants were associated with risk of CRC (rs3740253: P = 0.0079, OR = 1.15, 95% CI 1.04-1.28; rs7071351: P = 0.0085, OR = 1.15, 95% CI 1.04-1.28). And plasmid containing mutant haplotypes containing all the three mutations (rs12263636 or rs3740253 and rs7071351) could most significantly increase luciferase expression, compared with any haplotype of the three mutations. The study explained the functional mechanism for the 10q22.3 loci and provided new insights into the prevention and treatment of CRC.

Colon metal stents as a bridge to surgery had no significant effects on the perineural invasion: a retrospective study.

PURPOSE: The long-term oncological effects of self-expandable metallic stent (SEMS) as a "bridge to surgery" are contradictory, and perineural invasion was supposed to be enhanced by the stenting. In this retrospective study, we compared the perineural invasion and the oncological outcomes between the stent as a bridge to surgery (SBTS)- and emergency surgery (ES)-treated patients to evaluate the results of stenting on the perineural invasion. METHODS: The clinical data of patients with acute intestinal obstruction caused by colorectal cancer from January 2013 to January 2017 were retrospectively collected. Forty-three patients underwent semi-elective curative resection after endoscopic SEMS insertion, and sixty-three underwent ES. The adverse events and long-term follow-up outcomes were assessed. The clinicopathological characteristics, perineural invasion rates, and survival rates were compared between the two patient groups. RESULTS: Stent insertion resulted in significantly lower stoma rate (32.6% vs 46%; P = 0.03), post-operative overall complication rate (11.6% vs 28.6%, P = 0.038), and total hospital stay (17.07 ± 5.544 days vs 20.48 ± 7.372 days, P = 0.042). Compared with the ES group, there was no significant increase in the incidence of peripheral invasion in the SBTS group (39.5% vs 47.6%, P = 0.411). No significant difference was noted in the survival rate and long-term prognosis between the SEMS and ES groups (P = 0.964). The technical success rate was 95.6%, and the clinical success rate was 97.7%. CONCLUSIONS: Preoperative colon stenting was an effective transitional method for colorectal cancer patients with complete obstruction. Short-term stent implantation had no significant effect on perineural invasion in patients with CRC.

Long-term tumour outcomes of self-expanding metal stents as 'bridge to surgery' for the treatment of colorectal cancer with malignant obstruction: a systematic review and meta-analysis.

PURPOSE: To explore the long-term oncological results of self-expanding metal stents (SEMS) as a surgical transition compared with those of simple emergency surgery. METHODS: A systematic review of studies involving long-term tumour outcomes comparing SEMS with emergency surgery was conducted. All studies included information on 3-year and 5-year survival rates, 3-year and 5-year disease-free survival (DFS) rates, and local and overall recurrence rates; the results were expressed as odds ratios. RESULTS: Overall, 24 articles and 2508 patients were included, including 5 randomised controlled trials, 3 prospective studies, and 16 retrospective studies. The 3-year survival rate (odds ratio (OR) = 0.88, 95% confidence interval (CI) 0.69-1.12, P = 0.05), 5-year survival rate (OR = 0.91, 95% CI 0.70-1.17, P = 0.67), 3-year DFS rate (OR = 1.14, 95% CI 0.91-1.42, P = 0.65), 5-year DFS rate (OR = 1.35, 95% CI 0.91-2.02, P = 0.17), overall recurrence rate (OR 1.04, 95% CI 0.77-1.41, P = 0.14), and local recurrence rate (OR 1.37, 95% CI 0.84-2.23, P = 0.92) were determined. There was no significant difference between the randomised and observational studies in the subgroup analysis, and the 5-year survival rate was higher in studies with a stent placement success rate of ≥ 95%. CONCLUSION: SEMS implantation was a viable alternative in malignant left colon obstruction as a transition to surgery; its long-term survival results, including 5-year DFS and overall survival, were equivalent to those of emergent surgery.

Oncological consequence of emergent resection of perforated colon cancer with complete obstruction after stent insertion as a bridge to surgery.

PURPOSE: Colonic perforation is a life-threatening complication after colonic stent insertion as a bridge to surgery for acute obstruction caused by colorectal cancer. The oncological consequence of colonic perforation after emergent surgical intervention was unknown. The aim of this short communication was to investigate whether or not the perforation and emergent surgery had obviously impact on the peritoneal recurrence and long-term survival of patients. METHODS: Data of the patients who underwent colorectal stenting as a bridge to surgery in 5 years from 2012 to 2017 was collected by the Endoscopical Surgery Group of Hubei. The perforated cases treated by emergent operation were retrospectively analyzed. RESULTS: During 5 years from 2012 to 2017, 116 cases of colorectal stenting as a bridge to surgery had been performed, and 7 patients had perforation after stent placement and treated by emergent surgery, including 1 case of synchronic liver metastasis treated by one-stage metastasectomy. One of the 7 patients died of septic shock after operation, and the remaining patients were followed up for 6-60 months. There was no evidence of abdominal implantation or extra-abdominal metastasis. CONCLUSION: This small case series implicated that colonic perforation after stent insertion for malignant colorectal obstruction treated by emergent surgery might not obviously increase the peritoneal implantation and metastasis.

Clinical Effectiveness of Endoscopic Stent Placement in Treatment of Acute Intestinal Obstruction Caused by Colorectal Cancer.

BACKGROUND Emergency endoscopic intestinal stenting has been applied with increasing frequency in colorectal cancer patients with acute intestinal obstruction. However, its clinical effectiveness as compared to emergency surgery remains controversial. MATERIAL AND METHODS The clinical data of 96 patients with acute intestinal obstruction caused by colorectal cancer from April 2012 to April 2018 were retrospectively collected. Statistical technique success rate, clinical success rate, operative time, average indwelling time of stent, complications, transition time to second-stage surgery, postoperative hospital stay, sputum rate, and postoperative infection rate were studied. RESULTS Endoscopic colonoscopy was successfully performed in 94 patients. The success rate of stent placement was 97.9%, and the average operative time was 35 minutes (range, 25-85 minutes). Forty-two patients underwent stage I colectomy after relief of the obstruction. The average stent retention time was 7 days (range, 5-15 days). Two patients suffered from anastomotic infection. Their intestinal preparation time, hospital stay, fistula rate, and infection rate were lower than those of patients undergoing emergency operation for colon cancer intestinal obstruction. A total of 52 patients with colon cancer underwent palliative stent placement. Three patients had complications, including 1 case of stent displacement in the palliative care group and 2 cases with perforation in the bridge surgery group. CONCLUSIONS Emergency endoscopic placement of an intestinal stent is safe and effective in the treatment of patients with acute intestinal obstruction caused by colorectal cancer. It is also a safe and simple procedure for patients receiving advanced palliative treatment, which greatly improves their quality of life and is easy for patients' families to accept.