Worldwide variations in colorectal cancer

Role of Genetic Ancestry in 1,002 Brazilian Colorectal Cancer Patients From Barretos Cancer Hospital

Background: Colorectal cancer (CRC) is the third most frequent and the second deadliest cancer worldwide. The ethnic structure of the population has been gaining prominence as a cancer player. The purpose of this study was to determine the genetic ancestry of Brazilian CRC patients. Moreover, we intended to interrogate its impact on patients' clinicopathological features.

Methods: Retrospective observational cohort study with 1,002 patients with CRC admitted from 2000 to 2014 at Barretos Cancer Hospital. Following tumor DNA isolation, genetic ancestry was assessed using a specific panel of 46 ancestry informative markers. Survival rates were obtained by the Kaplan–Meier method, and the log-rank test was used to compare the survival curves. Multivariable Cox proportional regression models were used to estimate hazard ratios (HRs).

Results: We observed considerable admixture in the genetic composition, with the following average proportions: European 74.2%, African 12.7%, Asian 6.5%, and Amerindian 6.6%. The multivariate analysis for cancer-specific survival showed that clinical stage, lymphovascular invasion, and the presence of recurrence were associated with an increased relative risk of death from cancer (p < 0.05). High African proportion was associated with younger age at diagnosis, while high Amerindian proportion was associated with the mucinous histological subtype.

Conclusions: This represents the larger assessment of genetic ancestry in a population of Brazilian patients with CRC. Brazilian CRC patients exhibited similar clinicopathological features as described in Western countries.

Impact: Genetic ancestry components corroborated the significant admixture, and importantly, patients with high African proportion develop cancer at a younger age.

Global Prevalence of Colorectal Neoplasia: A Systematic Review and Meta-Analysis

BACKGROUND & AIMS

Most colorectal cancers (CRC) arise from colorectal adenomas, yet there is not enough information on global prevalence to inform health care policy. We examined the prevalence of any type of adenomas, advanced adenomas (AADs), and CRC according to age, sex, ethnicity, geographic regions, and anatomic location (proximal vs distal).

METHODS

MEDLINE and Embase were searched from their inception through May 1, 2018, to identify population-based, observational studies that reported the prevalence of colorectal neoplasia. Studies on participants 15 years or older, with a sample size of 500 persons or more, were included. Metaprop (College Station, TX) was used to model within-study variability by binomial distribution and Freeman-Tukey Double Arcsine Transformation to stabilize the variances. The prevalence figures were presented by proportions and their 95% CIs using random-effects models.

RESULTS

Our meta-analysis included 70 studies involving 637,414 individuals. The overall prevalence rates of adenoma (23.9%; 95% CI, 22.2%-25.8%), AAD (4.6%; 95% CI, 3.8%-5.5%), and CRC (0.4%, 95% CI, 0.3%-0.5%) were calculated. Subgroup analysis indicated that prevalence values (adenomas, AADs, and CRCs) were higher among men (29.7%, 6.5%, and 0.8%, respectively) than women (19.3%, 3.8% and 0.4%, respectively), among older adults (25.9%, 5.2%, and 0.6%, respectively) than younger adults (14.6%, 1.6%, and 0.1%, respectively), among Caucasians (23.7%, 6.6%, and 0.5%, respectively) than other ethnicities, in European countries (25.9%, 8.4%, and 0.8%, respectively) than other countries, and among patients with proximal (25.9%, 5.3%, and 0.1%, respectively) vs distal neoplasia.

CONCLUSIONS

In a systematic review and meta-analysis, we found a high prevalence of colorectal neoplasia among some populations. This indicates a need to expand CRC screening programs for these groups. The pooled prevalence estimates can be used as quality indicators for established CRC screening programs.

Effect of Tumor Location on Clinicopathological and Molecular Markers in Colorectal Cancer in Eastern China Patients: An Analysis of 2,356 Cases

Colorectal cancer (CRC) has become a major health concern in China due to its increasing incidence and mortality. This study aimed to clarify the relationship between tumor locations and the clinicopathological molecular marker features in eastern China CRC patients. We continuously collected data on 2,356 CRC patients who underwent surgical resection from January 2017 to April 2019. Right-sided colorectal cancer (RCC), was located from the cecum to the transverse colon and left-side colorectal cancer (LCRC) was located from the splenic flexure to the rectum. The clinicopathological indices (including age, sex, pTNM stage, mucinous production, and distant metastasis) and frequency of molecular markers such as KRAS, NRAS, BRAF, and microsatellite instability (MSI) were statistically analyzed between the RCC and LCRC groups. The associations between clinicopathological characters and molecular markers were also investigated. LCRC and RCC proportions in eastern China CRC patients were 81.75% and 18.25%, respectively. RCC (vs. LCRC) was more frequently observed with higher frequencies of MSI-high (MSI-H) and BRAF mutations in female and younger patients, and was closely associated with metastasis, poor differentiation, and mucinous tumors. Tumor location also showed significant differences in bowel wall infiltration degree and pTNM stage. Mutation rates of KRAS, NRAS, MSI, and BRAF were 40.15%, 3.85%, 6.31%, and 2.30%, respectively. Patients with a KRAS mutation tended to be female, had mucinous, perineural invasive, and polypoid tumor. Those with NRAS mutation tended to develop well-differentiated ulcerative tumors. The BRAF mutation was more relevant with lymph node involvement, deeper infiltration of the bowel wall, mucinous, poorly-differentiated tumor with thrombus, and perineural invasion. Furthermore, MSI-H was more commonly found in younger patients with deeper bowel wall infiltration and a poorly-differentiated polypoid tumor, whereas MSS patients tended to develop lymph node involvement, and a mucinous and perineural invasive tumor. In our study, we found that LCRC and RCC showed different features on the clinicopathological and molecular markers in eastern China CRC patients. Since our data differ from those of Western countries and other regions in China, further studies are required to clarify the regional differences of the clinicopathological and molecular markers in CRC patients.

Tumor Targeted Curcumin Delivery by Folate-Modified MPEG-PCL Self-Assembly Micelles for Colorectal Cancer Therapy

Introduction

Curcumin (Cur) is a natural extract of Asian spice Curcumin longa, showing multi-targeting capability and low toxicity in anti-tumor activities. The low bioavailability restricts its application as a therapeutic agent. Folate (FA) receptors are highly expressed in many malignant tumors while low expressed in normal tissue. Herein, we developed a self-assembled FA modified MPEG-PCL micelle to incorporate Cur (FA/Nano-Cur) and applied it for colorectal cancer therapy.

Methods

We prepared FA/Nano-Cur micelles and identified their characteristics. The drug release behavior, pharmacokinetics and in vitro anti-tumor activities of FA/Nano-Cur were studied. Furthermore, the in vivo anti-tumor ability assessment and anti-tumor mechanisms investigation were carried out in murine colorectal cancer model.

Results

FA/Nano-Cur micelles had an average particle size of 30.47 nm. Elongated T_1/2 and larger AUC were found in FA/Nano-Cur group than that in the Free Cur group. MTT assay and apoptotic study indicated the growth inhibitory effect and pro-apoptotic effect of FA/Nano-Cur were the most significant among all treatments. Moreover, the in vivo study demonstrated that FA/Nano-Cur micelles exhibited a much stronger effect to suppress tumor growth, promote tumor apoptosis and attenuate tumor angiogenesis than Free Cur and Nano-Cur micelles.

Conclusion

The present study demonstrated FA/Nano-Cur micelles might be a promising therapeutic agent in colorectal cancer treatment with distinctive advantages of improved bioavailability, sustained drug release, tumor-targeted delivery and low toxicity.

Enzyme and Transporter Kinetics for CPT-11 (Irinotecan) and SN-38: An Insight on Tumor Tissue Compartment Pharmacokinetics Using PBPK

BACKGROUND

Computational tools are becoming more and more powerful and comprehensive as compared to past decades in facilitating pharmaceutical, pharmacological and clinical practice. Anticancer agents are used either as monotherapy or in combination therapy to treat malignant conditions of the body. A single antineoplastic agent may be used in different types of malignancies at different doses according to the stage of the disease.

OBJECTIVE

To study the behavior of CPT-11 (Irinotecan) and its metabolite SN-38 in tumor tissue compartment through the Whole Body-Physiologically Pharmacokinetics (WB-PBPK) and to determine the activity of metabolic enzymes and transporters participating in the disposition of CPT-11 and SN-38 working in their physiological environment inside the human body.

METHODS

Whole body PBPK approach is used to determine the activity of different metabolic enzymes and transporters involved in the disposition of CPT-11 and its active metabolite, SN-38. The concentrations and pharmacokinetic parameters of the parent compound and its metabolite administered at clinically applicable dose via the intravenous route in the tumor tissue are predicted using this approach.

RESULTS

The activity rate constants of metabolic enzymes and transporters of CPT-11 are derived at their natural anatomic locations. Concentration-time curves of CPT-11 and SN-38 with their 5th to 95th percentage range are achieved at the tumor tissue level. Mean tumor tissue pharmacokinetics of both compounds are determined in a population of 100 individuals.

CONCLUSION

Tumor tissue concentration-time curves of CPT-11 and SN-38 can be determined via PBPK modeling. Rate constants of enzymes and transporters can be shown for healthy and tumor bearing individuals. The results will throw light on the effective concentration of active compound at its target tissue at the clinically applied IV dose.

CXCL-13 Regulates Resistance to 5-Fluorouracil in Colorectal Cancer

Purpose

5-Fluorouracil (5-Fu) is used as a conventional chemotherapy drug in chemotherapy for patients with advanced colorectal cancer, but many patients still suffer from treatment failure due to 5-Fu resistance. Emerging observations revealed the important role of chemokine (C-X-C motif) ligand 13 (CXCL-13) in tumor microenvironment and its relationship with prognosis in patients with colorectal cancer. This study is designed to reveal the important role of CXCL-13 in causing colorectal cancer resistance to 5-Fu.

Materials and Methods

CXCL-13 levels of patient's serum or cell culture supernatants were measured separately by enzyme-linked immunosorbent assay. In cell assays, cell viability is detected by Cell Counting Kit-8. Therefore, the recombinant human CXCL-13 was used to simulate its high expression in cells while its antibody and siRNA were used to reduce CXCL-13 expression in cells.

Results

In this study, we demonstrated that CXCL-13 is associated with 5-Fu resistance by culture medium exchange experiments and cytokine arrays of colorectal cancer resistant and non-resistant cells. Clinical studies showed that CXCL-13 is highly expressed in the serum of 5-Fu–resistant patients. High levels of serum CXCL-13 also predict a worse clinical outcome. The addition of recombinant CXCL-13 cytokine resulted in 5-Fu resistance, while its antibody overcame 5-Fu resistance, and knockdown of CXCL-13 expression by siRNA also reduced 5-Fu resistance, which can be saved by added recombination CXCL-13.

Conclusion

These results not only identify a CXCL-13 mediated 5-Fu resistance mechanism but also provide a novel target for 5-Fu–resistant colorectal cancer in prevention and treatment strategies.

Treatment Outcomes of Patients With Colorectal Cancer Enrolled in a Comprehensive Benefits Program of the National Insurance System in the Philippines: Data From the Pilot Site

PURPOSE

Cancer treatment causes significant financial burden, especially in developing countries such as the Philippines. This led the Philippine Department of Health to create the Z-Package colorectal cancer benefit program, an insurance system specifically designed to treat Filipinos with colorectal cancers with early to locally advanced-stage disease. The main goal of this program is to optimize treatment outcomes for this curable disease without causing financial toxicity.

MATERIALS AND METHODS

Three-year data on patients enrolled in the Z-Package colorectal cancer benefit program from 2016 to 2018 were reviewed by the University of the Philippines, Philippine General Hospital Colorectal Polyp and Cancer Study Group.

RESULTS

A total of 251 patients were enrolled in the Z-package colorectal cancer benefit program from 2016 to 2018. Mean age was 57 years old and a majority of patients (66%) were male. A majority of patients had rectal cancer (78%) and were diagnosed with stage III disease (82%). A majority (75%) were compliant to their treatment plans and clinic follow-up. Specifically, compliance to the prescribed surgery, chemotherapy, and/or radiation treatment were 90%, 77%, and 96%, respectively. Recurrence, morbidity, and mortality rates of enrolled patients in the Z-Package program from 2016 to 2018 were 17%, 22%, and 19%, respectively. Morbidities were mostly chemotherapy related (8%). Finally, patients in this program had a 2- and 3-year survival probability of 74% and 70%, respectively, which are comparable with data from more developed nations.

CONCLUSION

Results of this study include real-world data that show that when the highest standards of patient care are provided through a multidisciplinary team, patients' overall survival is also maximized.

A method for detecting tumor cells derived from colorectal cancer by targeting cell surface glycosylation with affinity capillary electrophoresis

Circulating tumor cells (CTCs) are involved in metastasis; thus, one of the most important approaches for identifying metastatic cancer is to detect CTCs in blood. In the present study, we examined whether directly analyzing cells with capillary electrophoresis (CE) could distinguish cancer cells from normal cells, based on differences in cell surface glycosylation. We compared human colorectal cancer (CRC) cell lines to a normal colon epithelium cell line. Our results demonstrated that direct CE analysis could successfully distinguish between CRC and normal cells with high reproducibility, based on migration times. We found that the weighted-average migration time was significantly shorter for CRC cells than for normal cells. Next, we observed changes in the electrophoretic behaviors of CRC cells by adding five different types of lectins. When Aleuria aurantia lectin was added, migration delays were observed in CRC cells, but not in normal colon cells. Therefore, by focusing on shifts in migration time after adding specific lectins, we could distinguish cancer cells from normal cells. These findings suggested that this diagnostic method of directly analyzing cells with CE after adding specific lectin(s) could be useful for detecting the difference in the sugar moieties on a surface of normal and cancer cells.

Integrative analysis and validation of dysregulated long non-coding RNAs in colon cancer

It is an increasing evidence that long non‐coding RNAs (lncRNAs) are involved in tumour initiation and progression. Here, we analysed RNA‐sequencing data from the Cancer Genome Atlas (TCGA) datasets. Totally, 1176lncRNAs, 245miRNAs and 2081mRNAs were identified to be differentially expressed (DE) in colon cancer tissues compared with normal tissues. CASC21, a novel lncRNA located in 8q24.21 locus, was significantly overexpressed in 30 colon cancer tissues compared with matched normal tissues by qRT‐PCR assay. CASC21 tended to higher expression as the increase of the tumour‐node‐metastasis (TNM) classification. Functionally, CASC21 promoted cell proliferation by regulating cell cycle and enhanced tumour metastasis by epithelial‐mesenchymal transition (EMT) in colon cancer. Mechanism study indicated that CASC21 might be involved in activating WNT/β‐catenin pathway in colon cancer. In addition, we also built a competing endogenous RNA (ceRNNA) network by bioinformatic analysis using TCGA datasets. Together, our results not only provide novel lncRNAs as potential candidates for further study but also prove that CASC21 is an oncogenic regulator through activating WNT/β‐catenin signalling in colon cancer.

Complete Genome Sequence of Lactobacillus plantarum Strain JDARSH, Isolated from Sheep Milk

Lactobacillus plantarum strain JDARSH, a potential probiotic with a wide range of functions, was isolated from sheep milk. Here, we report the whole-genome sequence of this bacterium. The draft genome yielded a 3.20-Mb genome and 2,980 protein-coding sequences.

Lactobacillus plantarum strain JDARSH, a potential probiotic with a wide range of functions, was isolated from sheep milk. Here, we report the whole-genome sequence of this bacterium. The draft genome yielded a 3.20-Mb genome and 2,980 protein-coding sequences.

Propofol suppresses proliferation and metastasis of colorectal cancer cells by regulating miR-124-3p.1/AKT3

BACKGROUND

Propofol, an extensively used intravenous anesthetic agents during cancer resection surgery, has been confirmed to execute anti-tumor effect on multiple cancers, including colorectal cancer (CRC). Although the role of propofol in CRC has been previously reported, its action mechanism remains poorly understood. This study further explored the biological function and underlying mechanism of propofol in CRC cells.

METHODS

The cell proliferation, migration and invasion were assessed by methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay, wound healing assay and transwell assay, respectively. The expression levels microRNA-124-3p.1 (miR-124-3p.1) and AKT serine/threonine kinase 3 (AKT3) was analyzed by quantitative real-time polymerase chain reaction. Western blot assay was employed to measure the protein expression of MMP-9, Vimentin and Cyclin D1. The interaction between miR-124-3p.1 and AKT3 was predicted by TargetScan and confirmed by dual-luciferase reporter assay.

RESULTS

Propofol inhibited CRC cell proliferation, migration and invasion. Knockdown of miR-124-3p.1 or AKT3 upregulation reversed the inhibitory effects of propofol on CRC cell proliferation and metastasis. Besides, AKT3 was a direct target of miR-124-3p.1 and its overexpression abated the anti-tumor effect of miR-124-3p.1 on CRC cell proliferation and metastasis.

CONCLUSION

Propofol inhibited CRC cell proliferation, migration and invasion by upregulating miR-124-3p.1 and downregulating AKT3, providing a new sight for propofol treatment of CRC.

Enterotoxigenic Bacteroides fragilis infection exacerbates tumorigenesis in AOM/DSS mouse model

The azoxymethane (AOM)/dextran sulfate sodium (DSS) murine model is commonly used to study colitis-associated cancer. The human commensal bacterium, enterotoxigenic Bacteroides fragilis (ETBF) secretes the Bacteroides fragilis toxin (BFT) which is necessary and sufficient to cause colitis. We report that BALB/c mice infected with WT-ETBF and administered three cycles of AOM/DSS developed numerous, large-sized polyps predominantly in the colorectal region. In addition, AOM/DSS-treated BALB/c mice orally inoculated with wild-type nontoxigenic Bacteroides fragilis (WT-NTBF) overexpressing bft (rETBF) developed numerous polyps whereas mice infected with WT-NTBF overexpressing a biologically inactive bft (rNTBF) did not promote polyp formation. Unexpectedly, the combination of AOM+ETBF did not induce polyp formation whereas ETBF+DSS did induce polyp development in a subset of BALB/c mice. In conclusion, WT-ETBF promoted polyp development in AOM/DSS murine model with increased colitis in BALB/c mice. The model described herein provides an experimental platform for understanding ETBF-induced colonic tumorigenesis and studying colorectal cancer in wild-type mice.

Survival Rates and Associated Factors of Colorectal Cancer Patients in Brunei Darussalam

Background:

Colorectal cancer (CRC) is the third most common cancer in both men and women. In most Asian countries, both the incidence and mortality rates of CRC are gradually increasing. In Brunei Darussalam, CRC ranks first and second in lifetime risk among men and women respectively. This study aims to report the overall survival rates and associated factors of CRC in Brunei Darussalam.

Methods:

This is a retrospective study examining CRC data for the period 2007 to 2017 retrieved from a population based cancer registry in Brunei Darussalam. A total of 728 patients were included in the analysis. Kaplan Meier method was used to estimate survival rates. Univariate analysis using log-rank test was used to examine the differences in survival between groups. Multivariate analysis using Cox PH regression was used to estimate hazard of death and obtain significant predictors that influence CRC patients’ survival.

Results:

The median survival time for colorectal, colon and rectal cancer patients were 57.0, 85.8 and 40.0 months respectively. The overall 1-, 3- and 5- year survival rates for CRC patients were 78.0%, 57.7% and 49.6% respectively. In univariate analysis, age at diagnosis, ethnicity, cancer stage, tumour location and histology were found to have significant difference in CRC patients’ survival. In the Cox PH analysis, older age (≥70 years), cancer stage, ethnicity and other histological type were determined as associated factors of CRC patients’ survival.

Conclusion:

This study found the overall 5-year survival rate of CRC in Brunei Darussalam is similar to that in some Asian countries such as Singapore and Malaysia. However, more efforts need to be carried out in order to raise awareness of CRC and improve the survival of CRC patients.

Multi-scale characterizations of colon polyps via computed tomographic colonography

Texture features have played an essential role in the field of medical imaging for computer-aided diagnosis. The gray-level co-occurrence matrix (GLCM)-based texture descriptor has emerged to become one of the most successful feature sets for these applications. This study aims to increase the potential of these features by introducing multi-scale analysis into the construction of GLCM texture descriptor. In this study, we first introduce a new parameter - stride, to explore the definition of GLCM. Then we propose three multi-scaling GLCM models according to its three parameters, (1) learning model by multiple displacements, (2) learning model by multiple strides (LMS), and (3) learning model by multiple angles. These models increase the texture information by introducing more texture patterns and mitigate direction sparsity and dense sampling problems presented in the traditional Haralick model. To further analyze the three parameters, we test the three models by performing classification on a dataset of 63 large polyp masses obtained from computed tomography colonoscopy consisting of 32 adenocarcinomas and 31 benign adenomas. Finally, the proposed methods are compared to several typical GLCM-texture descriptors and one deep learning model. LMS obtains the highest performance and enhances the prediction power to 0.9450 with standard deviation 0.0285 by area under the curve of receiver operating characteristics score which is a significant improvement.

Colon Cancer Prevention with Walnuts: A Longitudinal Study in Mice from the Perspective of a Gut Enterotype-like Cluster

There is limited understanding of how walnut consumption inhibits the development of colorectal cancer. A possible mechanism may involve alterations to the gut microbiota. In this study, the effects of walnut on gut microbiota were tested in a mouse tumor bioassay using the colonotropic carcinogen, azoxymethane (AOM) added to the total Western diet (TWD). 16S rRNA pyrosequencing identified three enterotype-like clusters (E1, E2, and E3) in this murine model. E1, E2, and E3 are associated with AOM exposure, walnut consumption, and TWD diet, respectively. E2 and E3 showed distinct taxonomic and functional characteristics, while E1 represented an intermediate state. At the family level, E1 and E3 were both enriched with Bacteroidaceae, but driven by two different operational taxonomic units (OTU; OTU-2 for E1, OTU-4 for E3). E2 was overrepresented with Porphyromonadaceae and Lachnospiraceae, with OTU-3 (family Porphyromonadaceae) as the "driver" OTU for this cluster. Functionally, E3 is overrepresented with genes of glycan biosynthesis and metabolism, xenobiotic metabolism, and lipid metabolism. E2 is enriched with genes associated with cell motility, replication and repair, and amino acid metabolism. Longitudinally, E2 represents the gut microbial status of early life in these mice. In comparison with E1 and E3, E2 is associated with a moderate lower tumor burden (P = 0.12). Our results suggest that walnuts may reduce the risk of colorectal cancer within a Western diet by altering the gut microbiota. Our findings provide further evidence that colorectal cancer risk is potentially modifiable by diet via alterations to the microbiota.

Interleukin-24 Regulates T Cell Activity in Patients With Colorectal Adenocarcinoma

Interleukin (IL)-24 plays a potential anti-tumor activity in colorectal cancer in a dose-dependent manner. However, the immunoregulatory role of IL-24 to peripheral and tumor-infiltrating T cell function in colorectal cancer was not fully elucidated. In this study, twenty-nine colorectal adenocarcinoma patients and fifteen healthy individuals were enrolled. IL-24 expression and IL-24 receptor (IL-20R1, IL-20R2, and IL-22R1) mRNA relative level was measured by ELISA and real-time PCR, respectively. CD4⁺ and CD8⁺ T cells were purified from peripheral bloods and cancer specimens, and were stimulated with low (10 ng/ml) and high (100 ng/ml) concentration of recombinant IL-24. CD4⁺ T cells activity was assessed by measurement of Th cell percentage, transcriptional factors, and cytokine production. CD8⁺ T cells activity was evaluated by investigation of cytotoxic molecules, target cell death, and interferon-γ (IFN-γ) secretion. IL-24 was decreasingly expressed in both peripheral bloods and cancer tissues in colorectal adenocarcinoma patients. However, IL-20R1 and IL-20R2 was comparable between healthy controls and colorectal adenocarcinoma patients. Low concentration of IL-24 suppressed CD4⁺ T cell proliferation. In contrast, high concentration of IL-24 not only promoted CD4⁺ T cell proliferation, but also enhanced CD4⁺ T cell activity, which mainly presented as up-regulation of Th1/Th17 frequency, T-bet/RORγt mRNA, and IFN-γ/IL-17 production but down-regulation of Treg percentage, FoxP3 mRNA, and IL-10/IL-35 secretion. Moreover, high concentration of IL-24 also increased perforin and granzyme B expression in CD8⁺ T cells, and elevated cytolytic and non-cytolytic activity of CD8⁺ T cells, which presented as induction of target cell death and elevation of IFN-γ expression. However, low concentration of IL-24 did not affect bioactivity of CD8⁺ T cells. The current data indicated that IL-24 might regulate T cell function in a dose-dependent manner. High-concentration of IL-24 might promote anti-tumor immune responses in development novel therapeutic approaches to colorectal adenocarcinoma.

Expression pattern of placenta specific 8 and keratin 20 in different types of gastrointestinal cancer

The aim of the present study was to investigate the expression of keratin 20 (KRT20) and placenta specific 8 (PLAC8) in gastrointestinal (GI) cancer with various differentiation phenotypes. The present study retrospectively investigated archived formalin-fixed paraffin-embedded tissue samples from 12 patients at different stages of GI cancer [four with gastric cancer, four with pancreatic cancer and four with colorectal cancer (CRC)]. The stages were pre-determined, according to differentiation phenotypes, by a pathologist of the Department of Pathology at Sijhih Cathay General Hospital. KRT20 and PLAC8 expression levels were assessed using immunohistochemistry. The CRC cell lines SW620 and Caco-2 were used to assess interactions between KRT20 and PLAC8 via reverse transcription-quantitative PCR. PLAC8 and KRT20 expression was observed consistently only in the well-differentiated CRC tissue samples. Low KRT20 expression levels were observed in the PLAC8 knockdown SW620 cells. In addition, there was a positive association between PLAC8 and KRT20 expression in the differentiated Caco-2 cells. According to the results of the present study, the differentiation status of GI cancer influenced KRT20 expression, particularly in CRC, which may explain why patients with well-differentiated CRC display better clinical outcomes. Therefore, the prognostic significance of KRT20 and PLAC8 may be particularly crucial for patients with CRC displaying a well-differentiated phenotype.

Deep learning techniques for detecting preneoplastic and neoplastic lesions in human colorectal histological images

Trained pathologists base colorectal cancer identification on the visual interpretation of microscope images. However, image labeling is not always straightforward and this repetitive task is prone to mistakes due to human distraction. Significant efforts are underway to develop informative tools to assist pathologists and decrease the burden and frequency of errors. The present study proposes a deep learning approach to recognize four different stages of cancerous tissue development, including normal mucosa, early preneoplastic lesion, adenoma and cancer. A dataset of human colon tissue images collected and labeled over a 10-year period by a team of pathologists was partitioned into three sets. These were used to train, validate and test the neural network, comprising several convolutional and a few linear layers. The approach used in the present study is 'direct'; it labels raw images and bypasses the segmentation step. An overall accuracy of >95% was achieved, with the majority of mislabeling referring to a near category. Tests on an external dataset with a different resolution yielded accuracies >80%. The present study demonstrated that the neural network, when properly trained, can provide fast, accurate and reproducible labeling for colon cancer images, with the potential to significantly improve the quality and speed of medical diagnoses.

Young patients with benign anal diseases and rectal bleeding: should a colonoscopy be performed?

BACKGROUND AND AIM

There is no consensus whether a colonoscopy should be recommended for patients under 50 years of age who present with both anal bleeding and benign anal diseases. The aim of this study is to evaluate the effectiveness of colonoscopy to detect neoplastic lesions in this specific group of patients.

METHODS

A prospective study analyzing the results of colonoscopies performed in patients younger than 50 years of age who reported a rectal bleeding and also had a diagnosis of benign anal disease at first clinical visit.

RESULTS

One hundred and eighty-seven consecutive patients were prospectively included in this study. In 35 patients (18.7%), adenomatous polyps were diagnosed. Thirty-seven percent of those lesions (13 cases) were further classified as either advanced adenomas or serrated adenomas. The prevalence of adenomas was 14.6% among patients under the age of 40 and 20% among those between 40 and 50 years of age. Thirty-one percent of the adenomas (11 cases) were located in the right colon, without any other concomitant lesion in the distal colon. In addition, an unsuspected case of sigmoid carcinoma was diagnosed.

CONCLUSION

The performance of colonoscopy in young patients with benign anal diseases and hematochezia resulted in a high rate of detection of neoplastic lesions. The method might be considered as a valid strategy of investigation in this frequent clinical situation.

Genomics and metagenomics of colorectal cancer

Colorectal cancer (CRC) is a common cancer globally. It is a complex disease influenced by genetic and environmental factors. Early studies on familial cases have identified major genes involved in CRC, such as proto-oncogenes KRAS, PIK3CA and BRAF, and tumour-suppressor genes APC and TP53. These genes have provided valuable insight into the molecular pathogenesis of CRC, and some have made ways to clinical utility to help diagnose cancer syndromes, prognosticate oncological outcomes and predict treatment responses. While these genetic factors are important, recent studies have suggested contribution of microorganisms to colorectal carcinogenesis. Observational studies, animal experiments and translational works have identified several microorganisms as potential carcinogenic bacteria, such as Fusobacterium nucleatum and Peptostreptococcus anaerobius. With the advent of sequencing technology and bioinformatics, more genomic and metagenomic factors are being uncovered as important players in CRC carcinogenesis. This article aims to review recent genomic and metagenomic discoveries relating to CRC.

The global, regional, and national burden of colorectal cancer and its attributable risk factors in 195 countries and territories, 1990-2017: a systematic analysis for the Global Burden of Disease Study 2017

BACKGROUND

Data about the global, regional, and country-specific variations in the levels and trends of colorectal cancer are required to understand the impact of this disease and the trends in its burden to help policy makers allocate resources. Here we provide a status report on the incidence, mortality, and disability caused by colorectal cancer in 195 countries and territories between 1990 and 2017.

METHODS

Vital registration, sample vital registration, verbal autopsy, and cancer registry data were used to generate incidence, death, and disability-adjusted life-year (DALY) estimates of colorectal cancer at the global, regional, and national levels. We also determined the association between development levels and colorectal cancer age-standardised DALY rates, and calculated DALYs attributable to risk factors that had evidence of causation with colorectal cancer. All of the estimates are reported as counts and age-standardised rates per 100 000 person-years, with some estimates also presented by sex and 5-year age groups.

FINDINGS

In 2017, there were 1·8 million (95% UI 1·8-1·9) incident cases of colorectal cancer globally, with an age-standardised incidence rate of 23·2 (22·7-23·7) per 100 000 person-years that increased by 9·5% (4·5-13·5) between 1990 and 2017. Globally, colorectal cancer accounted for 896 000 (876 300-915 700) deaths in 2017, with an age-standardised death rate of 11·5 (11·3-11·8) per 100 000 person-years, which decreased between 1990 and 2017 (-13·5% [-18·4 to -10·0]). Colorectal cancer was also responsible for 19·0 million (18·5-19·5) DALYs globally in 2017, with an age-standardised rate of 235·7 (229·7-242·0) DALYs per 100 000 person-years, which decreased between 1990 and 2017 (-14·5% [-20·4 to -10·3]). Slovakia, the Netherlands, and New Zealand had the highest age-standardised incidence rates in 2017. Greenland, Hungary, and Slovakia had the highest age-standardised death rates in 2017. Numbers of incident cases and deaths were higher among males than females up to the ages of 80-84 years, with the highest rates observed in the oldest age group (≥95 years) for both sexes in 2017. There was a non-linear association between the Socio-demographic Index and the Healthcare Access and Quality Index and age-standardised DALY rates. In 2017, the three largest contributors to DALYs at the global level, for both sexes, were diet low in calcium (20·5% [12·9-28·9]), alcohol use (15·2% [12·1-18·3]), and diet low in milk (14·3% [5·1-24·8]).

INTERPRETATION

There is substantial global variation in the burden of colorectal cancer. Although the overall colorectal cancer age-standardised death rate has been decreasing at the global level, the increasing age-standardised incidence rate in most countries poses a major public health challenge across the world. The results of this study could be useful for policy makers to carry out cost-effective interventions and to reduce exposure to modifiable risk factors, particularly in countries with high incidence or increasing burden.

FUNDING

Bill & Melinda Gates Foundation.

Synchronous Neoplastic Lesions In Referred Patients With Colorectal Cancer: A Retrospective Cohort Study

Background

Synchronous neoplastic lesions are usually present in patients with colorectal cancer (CRC) at diagnosis or postoperative follow-up endoscopy. However, few studies have been published about the clinicopathological features of synchronous lesions, especially those of synchronous advanced neoplasia. This study aimed to describe synchronous lesions in patients with CRC because this knowledge may be useful for preventing the development of metachronous cancer.

Material and methods

We retrospectively reviewed 261 primary CRC cases with synchronous lesions referred to our hospital during a 4-year period. Personal history, habits, family history, characteristics of index cancer, and synchronous lesions were assessed.

Results

In total, the 261 patients with CRC had 812 synchronous adenomas and 146 advanced neoplasia. Diminutive, small, and large polyps made up 66.7%, 20.2%, and 13.1% of all lesions, respectively; 9.3% of diminutive and small adenomas were advanced neoplasia, and 45.2% of synchronous advanced lesions were subcentimeter polyps. Both synchronous non-advanced lesions and advanced lesions developed most frequently in the distal colon, followed by the proximal colon, and were least frequently found in the rectum (P < 0.001). Older age (P = 0.04) and male gender (P = 0.001) were associated with the presence of advanced neoplasia in CRC cases with synchronous neoplastic lesions. Meanwhile, the use of aspirin may be associated with a lower incidence of advanced neoplasia (P = 0.04).

Conclusion

Patients diagnosed with CRC require detailed clearing of the remainder of the colon at baseline coloscopy or postoperative follow-up examination, and we should take a more cautious approach to synchronous subcentimeter polyps in this group of patients.

Expression and Clinical Significance of POLR1D in Colorectal Cancer

PURPOSE

RNA polymerase I subunit D (POLR1D) is involved in the synthesis of ribosomal RNA precursors and small RNAs, but its mechanism in the development and progression of colorectal cancer (CRC) remains ambiguous. Thus, this research aimed to investigate POLR1D's expression and significance in human CRC patients and evaluate its association with clinicopathological characteristics.

METHODS

Matched fresh-frozen cancerous and non-cancerous tissues were collected from 100 patients diagnosed with CRC. Immunohistochemical, Western blot, and quantitative real-time polymerase chain reaction analyses were adopted to validate the correlation between POLR1D expression and clinicopathological parameters in CRC tissues and adjacent normal tissues (ANTs).

RESULTS

POLR1D expression in CRC tissues was significantly higher than in the ANTs. χ2 test and Spearman's correlative analysis showed that a high POLR1D expression is significantly associated with clinical stage, Dukes stage, tumor differentiation, depth of invasion, and metastasis (p < 0.05). It is not correlated with gender, age, and tumor location and size (p > 0.05). Kaplan-Meier survival curves show that the overall survival (OS) time for the low expression group is remarkably longer than for the high expression group (p < 0.0015). Univariate and multivariate analyses indicate that a high POLR1D expression is an independent prognostic factor for poor OS (p = 0.000).

CONCLUSION

The findings of this study strongly indicate that POLR1D plays a pivotal role in the occurrence and progression of CRC. It might be an independent adverse prognostic factor for CRC patients and could serve as a potential therapeutic target for clinical diagnosis in CRC and anticancer drug development.

High expression of FABP4 and FABP6 in patients with colorectal cancer

Objective

To explore the relationship between FABP4 and FABP6 expression and the pathogenesis of colorectal cancer (CRC) and their potential as biomarkers in the diagnosis of CRC.

Methods

In total, 100 CRC patients and 100 controls were enrolled. The serum levels of FABP4 and FABP6 were detected by enzyme-linked immunosorbent assay (ELISA) before and 2 weeks after radical resection of CRC. The protein expressions of FABP4 and FABP6 were observed in colorectal tumor tissues and adjacent tissues by immunohistochemistry and western blot, respectively. The diagnostic performance of FABP4 and FABP6 in patients with CRC was evaluated by receiver operating characteristic (ROC) curve analysis.

Results

The serum levels of FABP4 and FABP6 in patients with CRC were higher than the levels in the controls before surgery (P < 0.001), and significantly decreased at 2 weeks after operation (P < 0.001). Immunohistochemistry showed that FABP4 and FABP6 were mainly distributed in the cytoplasm of human colorectal tumor tissues, and only a small amount distributed in adjacent tissues. Western blot revealed that the protein expressions of FABP4 and FABP6 were significantly higher in tumor tissues than in adjacent tissues (P < 0.001, P = 0.002, respectively). Tumors with high and low FABP4 and FABP6 expression have no significant correlation in tumor size, tumor site, distant organ and lymph node metastasis, histologic grade, lymphatic permeation, neurological invasion, vascular invasion, and Duke’s and TNM classification. Multivariate logistic regression analysis showed that FABP4 and FABP6 were independent risk factors for CRC (adjusted odds ratio 1.916; 95%CI 1.340–2.492; P < 0.001; adjusted odds ratio 2.162; 95%CI 1.046, 1.078); P < 0.001, respectively). In discriminating CRC from the normal control, the optimal sensitivity of FABP4 and FABP6 were 93.20% (95%CI 87.8–96.7) and 83.70% (95%CI 76.7–89.3), respectively, while the optimal specificity of FABP4 and FABP6 were 48.8% (95%CI 39.8–57.9) and 58.4% (95%CI 49.2–67.1), respectively. When combined detection of serum carcinoembryonic (CEA) and FABP4 and FABP6, the optimal sensitivity and specificity were 61.33% (95%CI 53.0–69.2) and 79.82% (95%CI 71.3–86.8), respectively.

Conclusion

Increased expression of FABP4 and FABP6 not only were strong risk factors for the development of CRC but could also represent a potential biomarker for CRC diagnosis in Chinese patients. Combined detection of CEA with FABP4 and FABP6 could improve the diagnostic efficacy of CRC.

Hepatocyte Nuclear Factor 3β Plays a Suppressive Role in Colorectal Cancer Progression

Background and Objective: Hepatocyte nuclear factor 3β (HNF3β) is a key transcription factor in the development of the gastrointestinal tract. However, only few studies have examined its' expression, function and potential clinical significance in colorectal cancer tumorigenesis and progression.

Methods: HNF3β expression in colorectal cancer tissue samples of 174 patients was assessed by immunohistochemistry. The results were analyzed with respect to patients' clinicopathological characteristics and survival. Following the in vitro cell transfection, MTT, wound healing, and Transwell assays were used to test cell proliferation, migration, and invasion, respectively. Western blot was used to examine IL6, JAK1, and STAT3 protein expression. The potential for tumor formation was evaluated using a mouse xenograft model.

Results: HNF3β expression was lower in colon cancer tissue compared to normal tissue and correlated with UICC clinical stage (P = 0.001), depth of invasion (P = 0.004), regional lymph node metastasis (P = 0.007), distant metastasis (P = 0.048), and poor survival (P < 0.001) in patients with colorectal cancer. Furthermore, HNF3β overexpression impeded proliferation, migration and invasion of SW480 cells via JAK-STAT3 signaling in vitro. Moreso, HNF3β overexpression showed a significant growth inhibition of subcutaneous xenograft tumors in vivo.

Conclusions: The results show that HNF3β acts as a suppressor of colorectal cancer progression and decreased HNF3 β expression is closely related to the poor prognosis. Thus, HNF3β may be a potential molecular target for inhibition of colorectal cancer cells and development of new anti-tumor therapies.

Comprehensive analysis of the long noncoding RNA expression profile and construction of the lncRNA-mRNA co-expression network in colorectal cancer

Long noncoding RNAs (lncRNAs) have been shown to play important roles in various tumors including colorectal cancer (CRC). Here, we obtained data from RNA-sequencing analysis using 3 paired of CRC tissues and corresponding normal tissues. Through Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses, the biological functions of these dysregulated genes were identified. Moreover, we analyzed the expression levels of lncRNA PGM5-AS1 and B3GALT5-AS1 by quantitative real-time PCR (qRT-PCR) assay. To evaluate the accuracy of the lncRNA-mRNA co-expression network we built, we also detected PGM5 expression and analyzed the relationship between PGM5-AS1 and PGM5 in CRC. In addition, we explored the potential function of PGM5-AS1 in vitro and in vivo. In conclusion, we identified dysregulated lncRNAs and constructed the lncRNA-mRNA co-expression network in CRC. Then, we showed that the expression levels of PGM5-AS1, B3GALT5-AS1 and PGM5 were significantly downregulated in CRC tissues compared with corresponding normal tissues. Besides, PGM5-AS1 expression was positively associated with PGM5 expression. These findings were consistent with our RNA-sequencing data. Functionally, overexpression of PGM5-AS1 could induce cell apoptosis and cell cycle arrest in CRC. Animal study indicated that PGM5-AS1 overexpression inhibited CRC growth in vivo. This work provides dysregulated lncRNAs as candidates for further study in CRC. The lncRNA-mRNA co-expression network brings novel insights into further function research. More importantly, PGM5-AS1 is a critical tumor suppressor in CRC.

Chemopreventive efficacy of juniper berry oil (Juniperus communis L.) on azoxymethane-induced colon carcinogenesis in rat

The aim of this study was to investigate the chemopreventive effects of juniper berry (JB) oil on azoxymethane (AOM)-induced colon cancer in rats. Thirty-two male Wistar albino rats were allocated into four groups: Control, AOM, AOM + JB, and JB groups. Whereas the control group was fed with standard pellet feed, the AOM and AOM + JB groups were administered of AOM (15 mg/kg body weight) subcutaneously once every 2 weeks for 10 weeks. AOM + JB and JB groups additionally received JB oil (100 µl/kg) orally. At the end of the 16-week experimental period, blood and tissue samples were obtained from the rats following necropsy. The macroscopic findings showed that the application of JB oil significantly decreased adenoma and adenocarcinoma formation both numerically and dimensionally. Immunohistochemically, CEA, COX-2, and Ki-67 immune-expressions decreased, and the immune-expression of caspase-3 increased in AOM + JB treated rats. Additionally, JB oil supplementation ameliorated antioxidant defense systems and lipid peroxidation within the colon tissue of AOM + JB treated rats. These results reveal that the JB oil acted as a chemopreventive dietary agent, inhibiting cell proliferation and COX-2 expression and inducing apoptosis, resulting in a significant reduction in colon tumor formation.

Sevoflurane induces apoptosis and inhibits the growth and motility of colon cancer in vitro and in vivo via inactivating Ras/Raf/MEK/ERK signaling

AIMS

To investigate the effects of sevoflurane on proliferation, cell cycle, apoptosis, autophagy, invasion and epithelial-mesenchymal transition of colon cancer cell line SW480, and to explore its possible mechanism.

MATERIALS AND METHODS

SW480 and SW620 cells were treated with a mixture of 95% O₂+5% CO₂ containing different concentrations of sevoflurane (1.7% SAV, 3.4% SAV and 5.1% SAV) for 6 h. Meanwhile, we performed a rescue experiment by treating cells with the ERK pathway activator LM22B-10 prior to treatment of cells with 5.1% sevoflurane。 KEY FINDINGS: High concentration (5.1%) of sevoflurane significantly inhibited the proliferation and invasion of cells, causing G0/G1 phase arrest and promoted apoptosis and autophagy. 5.1% sevoflurane can participate in the regulation of EMT by regulating the expression of E-cadherin, Vimentin and N-cadherin proteins. LM22B-10 promoted proliferation and invasion of cancer cells and inhibited apoptosis and autophagy, while 5.1% sevoflurane could reverse the effect of LM22B-10 on the biological characteristics of cells. Sevoflurane can significantly inhibit tumor growth in SW480 cells transplanted nude mice. Moreover, 5.1% sevoflurane significantly increased the expression of p-Raf, p-MEK1/2, and p-ERK1/2 in SW480 cells and tumor tissues without affecting p-JNK and p-p38 proteins, meanwhile, 5.1% sevoflurane can inhibit the activation of ERK signaling pathway by LM22B-10 in vitro and in vivo.

SIGNIFICANCE

Sevoflurane can inhibit the proliferation and invasion of colon cancer cells, induce apoptosis and autophagy, and participate in the regulation of epithelial-mesenchymal transition, which may be related to its inhibition of the ERK signaling pathway.

Serum CNPY2 isoform 2 represents a novel biomarker for early detection of colorectal cancer

Since early diagnosis is very important for treating CRC, we decided to detect peripheral serum canopy fibroblast growth factor signaling regulator 2 (CNPY2) isoform 2 to verify its diagnostic value for CRC patients. Serum samples were collected from 430 CRC patients and 201 healthy controls. Enzyme-linked immunosorbent assay (ELISA) detection kits for CNPY2 isoform 2 were generated and then applied to measure serum CNPY2 isoform 2 concentrations. Serum carcinoembryonic antigen (CEA) and carbohydrate antigen 19-9 (CA19-9) were also measured. The median serum CNPY2 isoform 2 concentrations in all CRC patients were significantly higher than those in the healthy control group (all P<0.001). Those with stage I CRC presented the highest area under the receiver operating characteristic curve (AUC) for CNPY2 isoform 2 [0.707, 95% confidence interval (CI): 0.649-0.765, P<0.001]. The diagnostic efficiency of the combination of CNPY2 isoform 2, CEA and CA19-9 was significantly higher than that of each biomarker detected separately (all P<0.0167). Serum CNPY2 isoform 2 may be a valuable biomarker for the early detection of CRC and presents an improvement in the diagnostic efficiency by combination of CEA and CA19-9.

Does adjuvant chemotherapy improve the prognosis of patients after resection of pulmonary metastasis from colorectal cancer? A systematic review and meta-analysis

BACKGROUND

It remains controversial whether patients benefit from adjuvant chemotherapy (ACT) after resection of pulmonary metastasis (PM) from colorectal cancer (CRC). This meta-analysis was intended to evaluate the efficacy of ACT in patients after resection of PM from CRC.

METHODS

We systematically retrieved articles from PMC, PubMed, Cochrane Library, and Embase (up to March 5, 2019). Survival data, including overall survival (OS) and disease-free survival (DFS), were tested by hazard ratios (HRs) and 95% confidence intervals (CIs).

RESULTS

We included 18 cohort studies with a total of 3885 patients. The meta-analysis showed that ACT had no significant effect on OS (HR = 0.78; 95% CI = 0.60-1.03; P = 0.077) and DFS (HR = 0.91; 95% CI = 0.74-1.11; P = 0.339) in patients after resection of PM from CRC. There was no significant difference in OS (HR = 0.79; 95% CI = 0.42-1.50; P = 0.474) in patients after resection of PM from CRC treated with bevacizumab (BV). Subgroup analysis showed that ACT did not improve OS (HR = 0.86; 95% CI = 0.57-1.29; P = 0.461) in patients who had undergone previous resection of extra PM. ACT did not improve OS in patients who had positive hilar/mediastinal lymph node metastasis (HR = 0.80; 95% CI = 0.57-1.14; P = 0.22).

CONCLUSION

In conclusion, ACT does not provide survival benefits for patients after resection of PM from CRC. ACT and targeted agents (BV) are not suggested for these patients.

Progranulin sustains STAT3 hyper-activation and oncogenic function in colorectal cancer cells

Persistent activation of Signal Transducer and Activator of Transcription (STAT)3 occurs in a high percentage of tumors, including colorectal cancer (CRC), thereby contributing to malignant cell proliferation and survival. Although STAT3 is recognized as an attractive therapeutic target in CRC, conventional approaches aimed at inhibiting its functions have met with several limitations. Moreover, the factors that sustain hyper-activation of STAT3 in CRC are not yet fully understood. The identification of tumor-specific STAT3 cofactors may facilitate the development of compounds that interfere exclusively with STAT3 activity in cancer cells. Here, we show that progranulin, a STAT3 cofactor, is upregulated in human CRC as compared to nontumor tissue/cells and its expression correlates with STAT3 activation. Progranulin physically interacts with STAT3 in CRC cells, and its knockdown with a specific antisense oligonucleotide (ASO) inhibits STAT3 activation and restrains the expression of STAT3-related oncogenic proteins, thus causing cell cycle arrest and apoptosis. Moreover, progranulin knockdown reduces STAT3 phosphorylation and cell proliferation induced by tumor-infiltrating leukocyte (TIL)-derived supernatants in CRC cell lines and human CRC explants. These findings indicate that CRC exhibits overexpression of progranulin, and suggest a role for this protein in amplifying the STAT3 pathway in CRC.

Colorectal cancer fecal screening test completion after age 74, sources and outcomes in French program

BACKGROUND

Elderly patients aged at least 75 years old (Elderly_75), represent 45% of colorectal cancer (CRC) incidence. As others, the French Colorectal Cancer Screening Program (CRCSP) does not include Elderly_75. To date, there is little evidence to justify stopping screening at 74 years of age.

AIM

To describe CRC fecal screening test completion after age 74, source (CRCSP/Provider ordered) and outcomes of these tests.

METHODS

The study concerned 18704 Elderly_75 residing in eleven French districts (Ain, Doubs, Essonne, Haute-Saone, Hauts-de-Seine, Jura, Seine-Saint-Denis, Territoire-de-Belfort, Val-de-Marne, Val-d’Oise, Yonne), having performed a CRC screening test between January 2008 and December 2017. The tests performed in a circumstance of delayed response to a solicitation (DRS) from the local cancer screening managing center (Managing-Center) were distinguished from the tests non-solicited by the Managing-Center, performed after a recommendation by a General Practitioner (GP) or other provider ordered (RGP). DRS was any test realized by an Elderly_75 following an initial invitation from the Managing-Center with a maximum 24 mo after this invitation. Any Non-DRS test was considered RGP. The outcomes of these tests were described according to the circumstances of test completion.

RESULTS

Of 18995 screening-tests were performed at ages: 75 (83.5%), 76-80 (13.4%) and > 80 (3.1%) years old. Elderly_75 performed the screening test in a circumstance of DRS (71.9%) or RGP (28.1%). The proportion of the tests that could not be analyzed and not restarted was 13.2%. For these unanalyzed tests, the reason was age-related in 78.0% of cases, related to the laboratory’s refusal to analyze the test of people aged ≥ 77. Reported colonoscopy completion rate was 81.3%. For those 575 people with reported colonoscopy, no complication was listed. 18.0% of the 366 Elderly_75 with lesions had no anteriority in the CRCSP. The neoplasia (124 Low-risk-polyps, 159 High-risk-polyps, 13 Unspecified-polyps and 70 CRCs) detection rate was 19.3/1000 Elderly_75 screened and the CRC detection rate was 3.7/1000 Elderly_75 screened.

CONCLUSION

The high rate of colonoscopy completion after a positive test and the high proportion of screened lesions observed suggest that the lengthening of the screening period could allow significant detection of CRC and polyps that occur in Elderly_75 excluded from CRCSP.

Do Stage I Colorectal Cancers with Lymphatic Invasion Require a Different Postoperative Approach?

BACKGROUND

Although stage I colorectal cancer has an excellent prognosis after complete surgical resection, disease recurrence still occurs. This study aimed to assess prognostic risk factors in this early stage of disease.

METHODS

All non-neoadjuvantly treated stage I colon (CC) and rectal (RC) patients who underwent a surgical resection between 2004 and 2015 were identified. Clinicopathological differences and long-term oncological outcomes were compared.

RESULTS

CC patients (n = 433) were older and had more pre-existing comorbidities. RC patients (n = 86) were associated with more T2 tumors, venous invasion, and higher rates of 30-day morbidity. In multivariate analysis, lymphatic invasion was found to be an independent predictor for disease recurrence (OR 4.57, P = 0.010) and worse disease-free survival (HR 4.26, P = 0.012). This was particularly true for distant recurrence, with eight times higher hazard ratios when lymphatic invasion was present (HR 8.02, P < 0.001). T2 tumors were at risk, though no significant association was found (OR 3.86, P = 0.051; HR 3.61, P = 0.065, respectively).

CONCLUSIONS

Lymphatic invasion was strongly associated with worse DFS, in particular distant recurrence. This subgroup of stage I patients might benefit from a more intensive follow-up and maybe should be considered for adjuvant therapy.

An exploration of colorectal cancer incidence rates in North Dakota, USA, via structural equation modeling

PURPOSE

The state of North Dakota has one of the highest incidence rates for colorectal cancer in the USA. Its high incidence rate, coupled with a large variation in incidence rates among counties within the state, makes North Dakota a "natural laboratory" in which to investigate environmental clues to colorectal cancer. We conducted a hypothesis-generating study to explore potential determinants of colorectal cancer in North Dakota.

METHODS

We obtained county-specific incidence rates for North Dakota's 53 counties from the statewide cancer registry and corresponding data on county demographic, agricultural, and geophysical features from population-based sources. Candidate demographic/agricultural variables included median household income, population density, colorectal cancer screening rates, average farm size (in acres), and the percent of county fertilized. Geophysical variables included the uranium content of soil, residential radon levels, and source of drinking water (municipal or well water). Statistical analyses were performed via multivariate regression and structural equation modeling.

RESULTS

Colorectal cancer incidence rates across North Dakota counties varied 3-fold. The structural equation model identified a significant role for well water use (p < 0.05). This finding is consistent with studies that implicate well water in colorectal cancer.

CONCLUSIONS

Well water contains several agents, e.g., bacteria, disinfection by-products, and nitrates that are potent colorectal carcinogens. Studies of well water use and colorectal cancer risk at the individual level in North Dakota are warranted.

Gut Microbiome: A Promising Biomarker for Immunotherapy in Colorectal Cancer

Research has been driven towards finding therapy predictive biomarkers for colorectal cancer (CRC) with a special interest in studying the gut microbiome. Gut microbiome acts not only as a barrier to prevent bacterial invasion and infection, but it also affects the efficacy of hematopoietic-cell transplantation, chemotherapy, and immunotherapy. Recently, immunotherapy, which potentiates the host immune system, has revolutionized cancer therapy in general and CRC treatment specifically by increasing the quality of life and the survival of a subset of patients with this disease. In immunotherapy, the gut microbiome plays an important role in cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) blockade, programmed cell death protein 1 (PD-L1) mediation, and T cell stimulation. As such, this review will cover the role of gut microbiome in CRC, summarize approved immunotherapy treatments for CRC, and focus on the potential use of gut microbiome as a biomarker for immunotherapy.

Remarkable apoptotic pathway of Hemiscorpius lepturus scorpion venom on CT26 cell line

OBJECTIVE

Scorpion venom, considered as a treasure trove of various bioactive molecules, is a new approach to induce cancer cell death via apoptosis pathways. In the present study, we evaluated for first time the anti-proliferative efficacy of Hemiscorpius lepturus scorpion venom and its pathway on a colon carcinoma cell.

MATERIALS AND METHODS

The CT26 and VERO cell lines were treated with various concentrations of the venom. The IC50 values were estimated by MTT assay test, and the apoptosis was evaluated by flow cytometry. Moreover, RT-PCR analysis was used to investigate the levels of Bax, Bcl2, Trp53, and Casp3 mRNA expression. The mice xenograft model was established to evaluate the therapy efficiency of venom. Some valuable exponential growth parameters were evaluated in treated mice.

RESULT

The scorpion venom inhibited the growth of CT26 cells with an IC50 value about 120 μg/ml. However, VERO cells increased to 896 μg/ml under the same condition. A remarkable apoptotic cells in CT26 cells were revealed by flow cytometry assay. A significant over-expression was observed in Bax, Casp3, and Trp53 and downregulated in Bcl2 mRNA level in tumor tissue after treatment with scorpion venom (p < 0.05). All changes of valuable exponential growth parameters showed a shrinking tumor size.

CONCLUSION

Our findings indicated that Hemiscorpius lepturus venom has a special anti-proliferative effect on CT26 cells via Trp53/Bcl2/Casp3 pathway. Considering its powerful cytotoxic vigor against a colon cancer cell (CT26) and low toxicity to non-tumorigenic cell (VERO), we propose that this venom probably has a specific effect on other colon cancer cells and may turn out to be a novel therapeutic strategy in treating colon cancer.

Direct and sensitive detection of circulating miRNA in human serum by ligase-mediated amplification

MicroRNAs (miRNA) involve in regulating different physiological processes whose dysregulation is associated with a wide range of diseases including cancers, diabetes and cardiovascular problems. Herein, we report a direct, sensitive and highly selective detection assay for circulating microRNA (miRNA). This detection strategy employs magnetic nanoparticles as the reaction platform which can not only allow online pre-concentration and selective separation but also integrates ligation reaction with amplification to enhance the sensitivity of the detection assay. With the presence of the target miRNA, the locked nucleic acid (LNA)-modified molecular beacon (MB) opens up, exposing the binding sites at two ends. The 3'- and 5'-end of the MB responsible for the attachment onto the magnetic nanoparticles, and reporting probe for the attachment of the pair of amplification probes respectively. The ligase ligate RNA to DNA enhance the amplification efficiency. Upon labelled with intercalating fluorophores (YOYO-1) on the hybrids, the quantification of the target miRNA was determined by measuring the fluorescence intensity. A detection limit of 314 fM was achieved with trace amount of sample consumption (~20 μL). As a proof of concept, miRNA-149 was chosen as the target miRNA. This assay is capable of discriminating single-base and reliably quantifying circulating miRNA-149 in both healthy and cancer patient's serums. The result obtained was comparable with that of quantitative reverse transcription polymerase chain reaction (qRT-PCR), suggesting that this direct and sensitive assay can be served as a promising, non-invasive tool for early diagnosis of breast cancer and colorectal cancer.

General anesthesia combined with epidural anesthesia maintaining appropriate anesthesia depth may protect excessive production of inflammatory cytokines and stress hormones in colon cancer patients during and after surgery

The purpose of this study was to investigate the influences of varied anesthetic methods and depths on inflammatory cytokines and stress hormone levels in radical operation among colon cancer patients during perioperative period.A total of 120 patients were collected in the study and randomly divided into 4 groups, A: general anesthesia + Narcotrend D1, B: general anesthesia + Narcotrend D2, C: general anesthesia + epidural anesthesia + Narcotrend D1, D: general anesthesia + epidural anesthesia + Narcotrend D2. The levels of tumor necrosis factor (TNF)-α, interleukin (IL)-6, IL-10, cortisol (Cor), adrenocorticotropic hormone (ACTH), and endothelin-1 (ET-1) were measured adopting commercial kits before anesthesia (T0), 4 hours after surgery (T1), 24 hours after surgery (T2), and 72 hours after surgery (T3).There was no significant difference in basic clinical characteristics among the groups. In comparison with group A, B and C, group D showed significantly lower levels of TNF-α, IL-6, IL-10, Cor, ACTH, and ET-1 at T1 and T2 (all, P < .05). Significantly higher levels of TNF-α, IL-6, IL-10, Cor, and ACTH were detected at T1 and T2 than those at T0 (all, P < .05), whereas, at T3, the levels of inflammatory cytokines and stress hormones were all decreased near to preoperation ones.General anesthesia combined with epidural anesthesia at Narcotrend D2 depth plays an important role in reducing immune and stress response in patients with colon cancer from surgery to 24 hours after surgery.

Extraction of Lipophilic Fraction from Polished Rice Improves Its Ameliorative Effect on Intestinal Impairment

Glucosylceramide (GlcCer), a major sphingolipid in plants and fungi, is known to have food functions such as preventing intestinal impairment and enhancing the moisture content of skin. However, there is little information about functions of GlcCer in food sources as most of the studies on GlcCer functions are done using purified GlcCer. This study was performed to investigate the effects of GlcCer contained in food on intestinal impairment; polished rice flour (RF) and this ethanol extract (RE) were used as sources of GlcCer, and these were evaluated by studying the formation of aberrant crypt foci (ACF) in 1,2-dimethylhydrazine (DMH)-treated mice, which is a model of colon cancer. Mice were fed with either a control diet, a RF diet where RF replaces cornstarch (150 g/kg), or a plus RE diet (0.5 g/kg; RE was extracted from the same amount of RF present in the RF diet). The amount of GlcCer was similar in both the RF and RE diets (3.0 and 2.7 mg/kg, respectively). DMH treatment induced the formation of ACF and the production of inflammation-related cytokines. Both dietary RF and RE suppressed ACF formation and RE, in particular, showed a significant suppressive effect. Dietary RE inhibited the production of almost all of the inflammation-related cytokines studied, while RF suppressed only a few of these cytokines. The present study suggests that the lipophilic fraction including GlcCer, present in polished rice has protective effects against intestinal impairment, but it requires extraction since digestion alone is not enough to elicit its complete protective action.

Downregulation of microRNA‑629‑5p in colorectal cancer and prevention of the malignant phenotype by direct targeting of low‑density lipoprotein receptor‑related protein 6

Aberrant expression of numerous microRNAs (miRNAs/miRs) in colorectal cancer (CRC) significantly affects disease progression. Recently, miR‑629‑5p (miR‑629) was identified as a tumor‑promoting miRNA in the malignant processes of a number of human cancers. However, few studies have been conducted regarding expression profiles and detailed roles of miR‑629 in CRC. In the present study, reverse transcription‑quantitative polymerase chain reaction was used to assess miR‑629 expression in CRC tissues and cell lines. Cell Counting Kit‑8 assay, flow cytometry and Transwell assays were performed to determine the in vitro effects of miR‑629 on CRC cell proliferation, apoptosis, and metastasis, respectively. Xenograft models were employed to determine the in vivo effects of miR‑629 on tumor growth in nude mice. Molecular mechanisms underlying the activity of miR‑629 in CRC cells were explored. miR‑629 expression decreased in CRC tissues and cell lines. The decreased aberrant miR‑629 expression was significantly associated with tumor size, lymphatic metastasis and tumor‑node‑metastasis stage of CRC, and was a predictor of poor prognosis. Restoring miR‑629 expression attenuated CRC cell proliferation, migration and invasion; promoted cell apoptosis in vitro; and inhibited tumor growth in vivo. Low‑density lipoprotein receptor‑related protein 6 (LRP6) was a direct target gene of miR‑629 in CRC cells. Furthermore, the effect of LRP6 knockdown was similar to that of miR‑629 overexpression in CRC cells. Restoration of LRP6 expression neutralized the effects of miR‑629 in CRC cells. miR‑629 suppressed the activation of the Wnt/β‑catenin pathway through LRP6 regulation both in vitro and in vivo. In conclusion, miR‑629 suppressed the development and progression of CRC by directly targeting LRP6 and inhibiting the Wnt/β‑catenin pathway both in vitro and in vivo. Therefore, miR‑629 may be a novel prognostic biomarker and therapeutic target in CRC.

Fusobacterium nucleatum-positive colorectal cancer

Colorectal cancer (CRC) is an important threat to human health and the fourth leading cause of mortality worldwide. Accumulating evidence indicates that the composition of the intestinal flora is associated with the occurrence of CRC. Fusobacterium nucleatum (Fn), one of the highly enriched bacteria in CRC tissues, invades the mucosa with adhesion factors and virulence proteins, interacts with the host immune system and promotes the occurrence and development of CRC and chemoresistance. Fn infection is prevalent in human colorectal carcinoma, although the infection rate varies in different regions. Fn may be used as a prognostic indicator of CRC. It is important to understand the multi-pathway carcinogenic mechanisms associated with CRC in order to develop novel antibacterial drugs against Fn. The current review summarizes the role of Fn and relevant research concerning CRC published in recent years, focusing on Fn infection in CRC, pathogenesis of Fn, Fn-positive CRC treatment, screening and prevention strategies against Fn-positive CRC.