Performance of the colorectal cancer screening marker Sept9 is influenced by age, diabetes and arthritis: a nested case-control study

Diagnostic performances of methylated septin9 gene, CEA, CA19-9 and platelet-to-lymphocyte ratio in colorectal cancer

BACKGROUND

This study was designed to compare the diagnostic efficacy of mSEPT9 to four blood markers (CEA, CA19-9, platelet-lymphocyte ratio (PLR) and neutrophil-lymphocyte ratio (NLR)). In addition, we aimed to determine the combined diagnostic efficacy of mSEPT9, CEA, CA19-9, PLR and NLR in colorectal cancer.

METHODS

A total of 567 participants were enrolled in the study, including 308 CRC patients, 61 colorectal polyp patients and 198 healthy subjects confirmed by colonoscopy and/or tissue biopsy. Plasma samples were collected for tests.

RESULTS

The positive rate of mSEPT9 in CRC (71.8%) was markedly higher than that in either the colorectal polyps group (27.9%) or the healthy controls (6.1%) (P < 0.001). The levels of CEA, CA19-9, NLR and PLR in the CRC group were significantly higher than those in the non-CRC groups (P < 0.05). ROC curves comparison analyses showed that the diagnostic efficacy of mSEPT9 alone in CRC was significantly higher than CEA, CA19-9, NLR and PLR alone. The combination of mSEPT9 with CEA, CA19-9 and PLR showed superior diagnostic value. In addition, binary logistic regression was also used to build a better model for clinical diagnosis of CRC. On univariable analyses, age, mSEPT9, CEA, CA 19-9, PLR and NLR were independent predictors of CRC. When these covariates were fitted in multivariable models, the ones with positive detection of mSEPT9, CEA, CA 19-9 and PLR were more likely to have CRC.

CONCLUSIONS

This research revealed a significant association between mSEPT9 status and the clinicopathological characteristics of CRC patients, and the combination of mSEPT9, CEA, CA19-9 and PLR could significantly improve diagnostic efficacy in CRC.

Expression of ten-eleven translocation 2 and glutathione-S-transferase pi in colorectal cancer patients with and without type 2 diabetes mellitus

AIMS

To highlight possible correlations of type 2 diabetes mellitus (T2DM) with microscopic / macroscopic characteristics of colorectal cancer tissues, along with the expression of Ten-Eleven Translocation 2 (TET2) and glutathione-S-transferase pi (GST-pi) proteins.

Taxonomic and functional profiling of fecal metagenomes for the early detection of colorectal cancer

Objectives

This study aimed to identify colorectal cancer (CRC)-associated phylogenetic and functional bacterial features by a large-scale metagenomic sequencing and develop a binomial classifier to accurately distinguish between CRC patients and healthy individuals.

Methods

We conducted shotgun metagenomic analyses of fecal samples from a ZhongShanMed discovery cohort of 121 CRC and 52 controls and SouthernMed validation cohort of 67 CRC and 44 controls. Taxonomic profiling and quantification were performed by direct sequence alignment against genome taxonomy database (GTDB). High-quality reads were also aligned to IGC datasets to obtain functional profiles defined by Kyoto Encyclopedia of Genes and Genomes (KEGG). A least absolute shrinkage and selection operator (LASSO) classifier was constructed to quantify risk scores of probability of disease and to discriminate CRC from normal for discovery, validation, Fudan, GloriousMed, and HongKong cohorts.

Results

A diverse spectrum of bacterial and fungi species were found to be either enriched (368) or reduced (113) in CRC patients (q<0.05). Similarly, metabolic functions associated with biosynthesis and metabolism of amino acids and fatty acids were significantly altered (q<0.05). The LASSO regression analysis of significant changes in the abundance of microbial species in CRC achieved areas under the receiver operating characteristic curve (AUROCs) of 0.94 and 0.91 in the ZhongShanMed and SouthernMed cohorts, respectively. A further analysis of Fudan, GloriousMed, and HK cohorts using the same classification model also demonstrated AUROC of 0.80, 0.78, and 0.91, respectively. Moreover, major CRC-associated bacterial biomarkers identified in this study were found to be coherently enriched or depleted across 10 metagenomic sequencing studies of gut microbiota.

Conclusion

A coherent signature of CRC-associated bacterial biomarkers modeled on LASSO binomial classifier maybe used accurately for early detection of CRC.

Progress in the field of noninvasive diagnostics for colorectal cancer: a systematic review for the accuracy of blood-based biomarkers for detection of advanced pre-cancerous lesions

BACKGROUND

Early detection of pre-cancerous adenomas through screening can reduce colorectal cancer (CRC) incidence. Fecal immunochemical tests are commonly used, but have limited sensitivity for pre-cancerous lesions. Blood-based screening may improve test sensitivity. This systematic review and meta-analysis was conducted to evaluate the accuracy of blood-based biomarkers for detection of advanced pre-cancerous lesions.

RESEARCH DESIGN AND METHODS

We present the accuracy of blood-based biomarkers for the detection of advanced pre-cancerous lesions. EMBASE, Web of Science and PubMed databases were searched, with study populations limited to adults diagnosed with advanced pre-cancerous lesions at colonoscopy, who had a blood-based biomarker test analyzed with reports of sensitivity and specificity.

RESULTS

69 studies were identified, which assessed 133 unique biomarkers sets. The best performing test was a panel of 6 miRNAs, with a sensitivity of 95% and specificity of 90% for advanced pre-cancerous lesions. Only 6 biomarkers demonstrated sensitivity ≥ 50% and specificity ≥ 90% for the detection of advanced pre-cancerous lesions.

CONCLUSION

Many different blood-based biomarkers have been assessed for detection of advanced pre-cancerous lesions, but few have progressed beyond the discovery stage. While some biomarkers have reported high sensitivity and specificity, larger prospective studies in unbiased intended-use screening populations are required for validation.

Novel Diagnostic Biomarkers in Colorectal Cancer

Colorectal cancer (CRC) is still a leading cause of cancer death worldwide. Less than half of cases are diagnosed when the cancer is locally advanced. CRC is a heterogenous disease associated with a number of genetic or somatic mutations. Diagnostic markers are used for risk stratification and early detection, which might prolong overall survival. Nowadays, the widespread use of semi-invasive endoscopic methods and feacal blood tests characterised by suboptimal accuracy of diagnostic results has led to the detection of cases at later stages. New molecular noninvasive tests based on the detection of CRC alterations seem to be more sensitive and specific then the current methods. Therefore, research aiming at identifying molecular markers, such as DNA, RNA and proteins, would improve survival rates and contribute to the development of personalized medicine. The identification of “ideal” diagnostic biomarkers, having high sensitivity and specificity, being safe, cheap and easy to measure, remains a challenge. The purpose of this review is to discuss recent advances in novel diagnostic biomarkers for tumor tissue, blood and stool samples in CRC patients.

[Value of plasma SEPTIN9 methylation detection for diagnosis and predicting radiosensitivity of esophageal carcinoma]

OBJECTIVE

To investigate the value of plasma mSEPT9 detection in the diagnosis and prediction of radiosensitivity of esophageal carcinoma.

METHODS

This study was conducted in 72 patients with esophageal cancer who received radical radiotherapy in the Department of Radiotherapy of First Affiliated Hospital of Bengbu Medical College between January, 2019 and December, 2020.Plasma mSEPT9 of the patients were examined with PCR before and after radiotherapy, with 20 healthy subjects from the physical examination center as the controls.The receiver operating characteristic curve (ROC) was used to assess the value of mSEPT9 in diagnosis of esophageal cancer, and the correlation between mSEPT9 and clinicopathological characteristics of the patients was analyzed.According to their response to radiotherapy, the patients were divided into radiosensitive group and insensitive group, and their plasma mSEPT9 levels were compared before radiotherapy.All the patients were observed for dynamic changes of mSEPT9 levels after radiotherapy to analyze the association of mSEPT9 variation with radiosensitivity of the tumors.

RESULTS

The sensitivity and specificity of mSEPT9 for the diagnosis of esophageal carcinoma were 62.5% and 100%, respectively, with an area under the ROC curve of 0.813.Plasma mSEPT9 level was correlated with lymph node metastasis and clinical stages of esophageal carcinoma (P < 0.05), but not with gender, age, invasion site, tumor length, degree of differentiation, or depth of invasion (P > 0.05).The radiosensitive patients had a significantly lower positivity rate for mSEPT9 than the insensitive patients before radiotherapy(53.06% vs 82.61%, P=0.016).In the 72 patients, the positivity rate for mSEPT9 decreased significantly after radiotherapy (30.56% vs 62.5%, P < 0.001); the positivity rate was significantly lowered after radiotherapy in the radiosensitive group (14.29% vs 53.06%, P < 0.001), but the reduction was not significant in the insensitive group (65.22% vs 82.61%, P=0.125).

CONCLUSION

Detection of plasma mSEPT9 level is helpful for diagnosis and prediction of radiosensitivity of esophageal carcinoma.

Identifying Novel Biomarkers Ready for Evaluation in Low-Prevalence Populations for the Early Detection of Lower Gastrointestinal Cancers: A Systematic Review and Meta-Analysis

INTRODUCTION

Lower gastrointestinal (GI) cancers are a major cause of cancer deaths worldwide. Prognosis improves with earlier diagnosis, and non-invasive biomarkers have the potential to aid with early detection. Substantial investment has been made into the development of biomarkers; however, studies are often carried out in specialist settings and few have been evaluated for low-prevalence populations.

METHODS

We aimed to identify novel biomarkers for the detection of lower GI cancers that have the potential to be evaluated for use in primary care. MEDLINE, Embase, Emcare and Web of Science were systematically searched for studies published in English from January 2000 to October 2019. Reference lists of included studies were also assessed. Studies had to report on measures of diagnostic performance for biomarkers (single or in panels) used to detect colorectal or anal cancers. We included all designs and excluded studies with fewer than 50 cases/controls. Data were extracted from published studies on types of biomarkers, populations and outcomes. Narrative synthesis was used, and measures of specificity and sensitivity were meta-analysed where possible.

RESULTS

We identified 142 studies reporting on biomarkers for lower GI cancers, for 24,844 cases and 45,374 controls. A total of 378 unique biomarkers were identified. Heterogeneity of study design, population type and sample source precluded meta-analysis for all markers except methylated septin 9 (mSEPT9) and pyruvate kinase type tumour M2 (TuM2-PK). The estimated sensitivity and specificity of mSEPT9 was 80.6% (95% CI 76.6-84.0%) and 88.0% (95% CI 79.1-93.4%) respectively; TuM2-PK had an estimated sensitivity of 81.6% (95% CI 75.2-86.6%) and specificity of 80.1% (95% CI 76.7-83.0%).

CONCLUSION

Two novel biomarkers (mSEPT9 and TuM2-PK) were identified from the literature with potential for use in lower-prevalence populations. Further research is needed to validate these biomarkers in primary care for screening and assessment of symptomatic patients.

Identification of DNA methylation markers for early detection of CRC indicates a role for nervous system-related genes in CRC

Purpose

Colonoscopy and the fecal immunochemical test (FIT) are currently the most widely used screening modalities for colorectal cancer (CRC), however, both with their own limitations. Here we aim to identify and validate stool-based DNA methylation markers for the early detection of CRC and investigate the biological pathways prone to DNA methylation.

Methods

DNA methylation marker discovery was performed using The Cancer Genome Atlas (TCGA) colon adenocarcinoma data set consisting of normal and primary colon adenocarcinoma tissue. The performance of the five best candidate markers and a previously identified marker, NDRG4, was evaluated on tissues and whole stool samples of healthy subjects and CRC patients using quantitative MSP assays. The results were compared and combined with FIT data. Finally, pathway and gene ontology enrichment analyses were performed using ToppFun, GOrilla and clusterProfiler.

Results

GDNF, HAND2, SLC35F3, SNAP91 and SORCS1 were ranked as the best performing markers. Gene combinations of all five markers, NDRG4 and FIT were evaluated to establish the biomarker panel with the highest diagnostic potential, resulting in the identification of GDNF/SNAP91/NDRG4/FIT as the best performing marker panel. Pathway and gene ontology enrichment analyses revealed that genes associated with the nervous system were enriched in the set of best performing CRC-specific biomarkers.

Conclusion

In silico discovery analysis using TCGA-derived data yielded a novel DNA-methylation-based assay for the early detection of CRC, potentially improving current screening modalities. Additionally, nervous system-related pathways were enriched in the identified genes, indicating an epigenetic regulation of neuronal genes in CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13148-021-01067-9.

Variables Associated with Detection of Methylated BCAT1 or IKZF1 in Blood from Patients Without Colonoscopically Evident Colorectal Cancer

BACKGROUND

DNA methylated in BCAT1 and IKZF1 are promising circulating tumor DNA (ctDNA) biomarkers for colorectal cancer detection. This study tested for variables that might be associated with their detection in patients without colonoscopically evident colorectal cancer so-called false positives.

METHODS

A retrospective review of demographic and clinical variables was conducted on patients who were assayed for these biomarkers prior to a colonoscopy for any indication. Potential relationships between detection of these biomarkers and patient variables in patients without colorectal cancer were identified by logistic regression. An age- and sex-matched case-control study was undertaken to identify additional associations.

RESULTS

A total of 196 of 1,593 patients undergoing colonoscopy were positive for BCAT1 and/or IKZF1 methylation; 70 (35.7%) had confirmed diagnosis of colorectal cancer. Of the 126 false positives, biomarker levels were significantly lower than in those with colorectal cancer (P < 0.05), with the total cell-free circulating DNA concentration associated with biomarker detection (OR, 1.16; 95% CI, 1.10-1.22), and 83 (65.9%) of the non-colorectal cancer cases positive for methylated BCAT1 only. Age ≥70 years was the only demographic variable associated with biomarker detection (OR, 4.31; 95% CI, 1.50-12.41). No significant associations were seen with medications or comorbidities (P > 0.05). Four cases without colonoscopically evident colorectal cancer but with biomarker levels above the median for patients with colorectal cancer were diagnosed with metastatic adenocarcinoma within 1 year.

CONCLUSIONS

False-positive results were most commonly associated with detection of methylated BCAT1 only, as well as age ≥70 years.

IMPACT

In the absence of colonoscopically evident colorectal cancer, a high level of circulating methylated DNA warrants investigations for cancers at other sites.

Age-stratified reference intervals unlock the clinical potential of circulating cell-free DNA as a biomarker of poor outcome for healthy individuals and patients with colorectal cancer

Circulating cell-free DNA (cfDNA) has spurred much interest as a biomarker in oncology. However, inter- and intra-individual cfDNA levels vary greatly. Consequently, in order to base clinical decisions on cfDNA measurements, normal reference intervals are essential to avoid that ordinary variation is confused with clinically relevant change. The lack of reference intervals may potentially explain the ambiguous results reported in the field. Our study aimed to establish reference intervals and to evaluate the association between cfDNA and demographic and clinical variables, including colorectal cancer (CRC). Plasma samples and clinical data from 2817 subjects were collected including 1930 noncancer individuals and 887 CRC patients. cfDNA was measured using droplet digital polymerase chain reaction (PCR). The large cohort combined with robust cfDNA quantification enabled establishment of reference intervals (<67 years: 775-4860 copies/mL; ≥67 years: 807-6561 copies/mL). A cfDNA level above the age-stratified 90% percentile was prognostic of reduced survival in both noncancer individuals and CRC patients, with HR values of 2.56 and 2.01, respectively. Moreover, cfDNA levels increased significantly with age, elevated BMI and chronic diseases. In CRC, the cfDNA level was increased for Stage IV, but not Stage I to Stage III cancer. In summary, the use of reference intervals revealed that high cfDNA levels were predictive of shorter survival in both noncancer individuals and CRC patients, and that CRC development did not affect the cfDNA level until metastatic dissemination. Furthermore, cfDNA levels were impacted by age and chronic diseases. Conclusively, our study presents reference intervals that will help pave the way for clinical utilization of cfDNA.

Fecal DNA methylation markers for detecting stages of colorectal cancer and its precursors: a systematic review

Background

DNA methylation biomarkers in stool may have applications in early colorectal cancer (CRC) detection; however, their association with stages of CRC carcinogenesis or their performance in detecting various stages is unclear. We aimed to systematically review the evidence for DNA methylation markers in stool for risk stratification or detection of specific CRC stages, as well as precursors of CRC.

Methods

We conducted a systematic search in line with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. We searched PubMed and ISI Web of Knowledge to identify relevant studies published until 14th January 2020. Two reviewers independently extracted data on study population characteristics, candidate genes, methylation measurement methods, odds ratios (ORs), overall and stage-specific sensitivities, specificities, areas under the receiver operating characteristics curve, and p-values for statistical significance for OR and for association of methylation levels with stage.

Results

Twenty-seven studies that reported stage-specific associations or performances of fecal DNA methylation markers for detecting colorectal neoplasms were identified. All studies used methylation-specific polymerase chain reaction for assessing methylation levels in the promoter or exon 1 regions of targeted genes. However, most studies were underpowered and limited by their case-control design. Furthermore, the stage-specific associations or sensitivities were validated for two markers (hypermethylation of GATA4 and VIM) only.

Conclusion

Methylation markers in stool may be useful for detection of CRC precursors or CRC staging, but promising candidate markers need to be validated in longitudinal studies on large screening populations, performing epigenome-wide analyses. Identification of stage-specific DNA methylation biomarkers in stool could boost current strategies towards early detection and enable different approaches to precision medicine for CRC.

Current status of development of methylation biomarkers for in vitro diagnostic IVD applications

A significant volume of research clearly shows that disease-related methylation changes can be used as biomarkers at all stages of clinical disease management, including risk assessment and predisposition screening through early diagnostics to personalization of patient care and monitoring of the relapse and chronic disease. Thus disease-related methylation changes are an attractive source of the biomarkers that can have significant impact on precision medicine. However, the translation of the research findings in methylation biomarkers field to clinical practice is at the very least not satisfactory. That is mainly because the evidence generated in research studies indicating the utility of the disease-related methylation change to predict clinical outcome is in majority of the cases not sufficient to postulate the diagnostic use of the biomarker. The research studies need to be followed by well-designed and systematic investigations of clinical utility of the biomarker that produce data of sufficient quality to meet regulatory approval for the test to be used to make clinically valid decision. In this review, we describe methylation-based IVD tests currently approved for IVD use or at the advanced stages of the development for the diagnostic use. For each of those tests, we analyze the technologies that the test utilizes for methylation detection as well as describe the types of the clinical studies that were performed to show clinical validity of the test and warrant regulatory approval. The examples reviewed here should help with planning of clinical investigations and delivery of the clinical evidence required for the regulatory approval of potential methylation biomarker based IVD tests.

Diagnostic performance of various liquid biopsy methods in detecting colorectal cancer: A meta-analysis

Liquid biopsy is a promising method in detecting colorectal cancer (CRC). However, previous meta‐analyses only focused on the diagnostic performance of cell‐free DNA (cfDNA). Therefore, we firstly evaluated the overall performance of all liquid biopsy methods. The pooled sensitivities, specificities, diagnostic odds ratios, and area under curve (AUC) of summary receiver operating characteristic curve for all liquid biopsy methods, exosomes, circulating tumor cells (CTCs), and cfDNA were calculated, respectively. A total of 62 articles involving 18 739 individuals were included. Fifty‐one articles were about cfDNA, five articles were about CTCs, and six articles were about exosomes. The overall performance of all liquid biopsy methods had a pooled sensitivity, specificity, and AUC of 0.77 (95% confidence interval [CI] 0.76‐0.78), 0.89 (95% CI 0.88‐0.90), and 0.9004, respectively. The sensitivities were 0.82 (95% CI 0.79‐0.85), 0.76 (95% CI 0.72‐0.80), and 0.76 (95% CI 0.75‐0.77) for CTCs, exosomes, and cfDNA, respectively. The specificities were 0.97 (95% CI95% CI 0.95‐0.99), 0.92 (95% CI 0.89‐0.94), and 0.88 (95% CI 0.87‐0.89) for CTCs, exosomes, and cfDNA, respectively. The AUC were 0.9772, 0.9037, and 0.8963 for CTCs, exosomes, and cfDNA, respectively. The overall performance of all liquid biopsy methods had great diagnostic value in detecting CRC, regardless of subtypes. Among all liquid biopsy methods, CTCs showed the best diagnostic performance.

Serum netrin-1 as a biomarker for colorectal cancer detection

BACKGROUND

Recent evidence support that netrin-1 involves in colorectal carcinogenesis.

OBJECTIVE

This study was to evaluate the performance of serum netrin-1 for detection of colorectal cancer (CRC) in both clinical/screening sets.

METHODS

A total of 115 consecutive patients with CRC and matched healthy controls were included in Clinical Set. Fifty subjects with CRC, 50 subjects with advanced adenoma (AA), and 150 matched control participants free of neoplasia were included in Screening Set.

RESULTS

In Clinical set, subjects with CRC presented higher levels of serum netrin-1 (513.9 ± 22.6 pg/mL) than controls (347.8 ± 20.3 pg/mL, p< 0.0001). Similar in Screening set, serum netrin-1 was higher in CRC (644.5 ± 37.0 pg/mL, both p< 0.0001), compared with controls (407.7 ± 14.8 pg/mL) and AA (416.5 ± 18.5 pg/mL). However, there was no difference between controls and AA (p= 0.752). Compared with the low netrin-1 group, the high group presented increased risk of CRC (Clinical set: OR = 4.300, p< 0.001; Screening set: OR = 7.731, p< 0.001). ROC curve of netrin-1 was developed to detect CRC (Clinical set: AUC 0.703; Screening set: AUC 0.759).

CONCLUSIONS

It suggests netrin-1 as a potential biomarker for CRC detection.

Utility of the methylated SEPT9 test for the early detection of colorectal cancer: a systematic review and meta-analysis of diagnostic test accuracy

Background

Circulating tumour DNA from colorectal cancer (CRC) is a biomarker for early detection of the disease and therefore potentially useful for screening. One such biomarker is the methylated SEPT9 (mSEPT9) gene, which occurs during CRC tumourigenesis. This systematic review and meta-analysis aims to establish the sensitivity, specificity and accuracy of mSEPT9 tests for the early diagnosis of CRC.

Methods

A systematic search of the relevant literature was conducted using Medline and Embase databases. Data were extracted from the eligible studies and analysed to estimate pooled sensitivity, specificity and diagnostic test accuracy.

Results

Based on 19 studies, the pooled estimates (and 95% CIs) for mSEPT9 to detect CRC were: sensitivity 69% (62-75); specificity 92% (89-95); positive likelihood ratio 9.1 (6.1-13.8); negative likelihood ratio 0.34 (0.27-0.42); diagnostic OR 27 (15-48) and area under the curve 0.89 (0.86-0.91). The test has a positive predictive value of 2.6% and negative predictive value of 99.9% in an average risk population (0.3% CRC prevalence), and 9.5% (positive predictive value) and 99.6% (negative predictive value) in a high-risk population (1.2% CRC prevalence).

Conclusion

The mSEPT9 test has high specificity and moderate sensitivity for CRC and is therefore a potential alternative screening method for those declining faecal immunochemical test for occult blood (FIT) or other screening modalities. However, it is limited by its poor diagnostic performance for precancerous lesions (advanced adenomas and polyps) and its relatively high costs, and little is known about its acceptability to those declining to use the FIT.

Circulating molecular biomarkers for screening or early diagnosis of colorectal cancer: which is ready for prime time?

According to recent statistics, colorectal cancer (CRC) is a frequent disease, the second most frequent malignancy in women and the third most common malignant disease in men, respectively. Although reinforced emphasis on CRC screening by means of immunochemical fecal occult blood test, colonoscopy or sigmoidoscopy has contributed to decrease cancer-related deaths, alternative diagnostic tests would be needed for establishing earlier and more potentially effective treatments. Innovative diagnostic techniques have recently emerged, some of which hold promises for screening and/or early CRC detection. Recent evidence suggests that the so-called "liquid biopsy", conventionally defined as detection and quantification of circulating tumor cells (CTCs) and cancer-related nucleic acids in peripheral blood, may allow earlier diagnosis of CRC combined with lower invasiveness and less patient inconvenience, higher throughput, faster turnaround time, inferior usage of healthcare resources and relatively low cost. Encouraging data have emerged from trials based on CTCs detection, though the sensitivity of the current diagnostic techniques is still perhaps insufficient for enabling early CRC diagnosis. Among the various biomarkers that can be detected with liquid biopsy, SEPT9 methylation displays good diagnostic performance and relatively high cancer detection rate (between 57-64% in patients with CRC stages 0-I), which would make this test a promising tool for population screening, alone or in combination with other conventional diagnostic investigations. Encouraging evidence has also been recently published for BCAT1/IKZF1 methylation. Regarding microRNA (miRNAs), the available evidence highlights that the combination of some of these biomarkers rather than the assessment of a single miRNA alone would enable efficient identification of early CRCs, though widespread clinical application is still challenged by a number of preanalytical, analytical and clinical issues.

Diagnostic Value and Clinical Significance of Methylated SEPT9 for Colorectal Cancer: A Meta-Analysis

Background

This meta-analysis aimed to clarify the diagnostic role of plasma methylated SEPT9 (mSEPT9) in colorectal cancer (CRC) and examined its association with CRC.

Material/Methods

A systematic review was conducted prior to July 2018. Summary sensitivity, specificity, and positive and negative likelihood ratio (PLR/NLR) were calculated for the diagnostic value of mSEPT9 for CRC. The areas under the receiver operating curves (AUCs) were used to summarize the overall test performance.

Results

Twenty-two studies with 2271 CRC patients were enrolled. The summary sensitivity, specificity, PLR, NLR, DOR, and AUC of the overall analysis of mSEPT9 were 0.69, 0.92, 8.1, 0.34, 24, and 0.89, respectively. Subgroup and meta-regression analyses demonstrated that the diagnostic value was higher for the Epi proColon 2.0 assay, Asian ethnicity, and mSEPT9 test combined with fecal occult blood test (FOBT) or fecal immunochemical test (FIT) than for other test methods, white ethnicity, and mSEPT9 test alone. The rate of mSEPT9 positivity was higher in advanced CRC cases compared with early-stage CRC cases, and was higher in CRC cases than in adenoma cases. No significant difference in mSEPT9 positivity rate was found between left- and right-sided CRC.

Conclusions

Plasma mSEPT9 has a high diagnostic value for CRC, especially on the newly developed Epi proColon test 2.0 method. The diagnostic sensitivity is superior among Asians compared to whites, and the combination of mSEPT9 and FOBT/FIT has a better performance than mSEPT9 alone. Finally, the expression of mSEPT9 is associated with CRC stage but not with location.

Cell-free tumour DNA testing for early detection of cancer - a potential future tool

In recent years, detection of cell-free tumour DNA (ctDNA) or liquid biopsy has emerged as an attractive noninvasive methodology to detect cancer-specific genetic aberrations in plasma, and numerous studies have reported on the feasibility of ctDNA in advanced cancer. In particular, ctDNA assays can capture a more 'global' portrait of tumour heterogeneity, monitor therapy response, and lead to early detection of resistance mutations. More recently, ctDNA analysis has also been proposed as a promising future tool for detection of early cancer and/or cancer screening. As the average proportion of mutated DNA in plasma is very low (0.4% even in advanced cancer), exceedingly sensitive techniques need to be developed. In addition, as tumours are genetically heterogeneous, any screening test needs to assay multiple genetic targets in order to increase the chances of detection. Further research on the genetic progression from normal to cancer cells and their release of ctDNA is imperative in order to avoid overtreating benign/indolent lesions, causing more harm than good by early diagnosis. More knowledge on the sources and elimination of cell-free DNA will enable better interpretation in older individuals and those with comorbidities. In addition, as white blood cells are the major source of cell-free DNA in plasma, it is important to distinguish acquired mutations in leukocytes (benign clonal haematopoiesis) from an upcoming haematological malignancy or other cancer. In conclusion, although many studies report encouraging results, further technical development and larger studies are warranted before applying ctDNA analysis for early cancer detection in the clinic.

Epigenetic IVD Tests for Personalized Precision Medicine in Cancer

Epigenetic alterations play a key role in the initiation and progression of cancer. Therefore, it is possible to use epigenetic marks as biomarkers for predictive and precision medicine in cancer. Precision medicine is poised to impact clinical practice, patients, and healthcare systems. The objective of this review is to provide an overview of the epigenetic testing landscape in cancer by examining commercially available epigenetic-based in vitro diagnostic tests for colon, breast, cervical, glioblastoma, lung cancers, and for cancers of unknown origin. We compile current commercial epigenetic tests based on epigenetic biomarkers (i.e., DNA methylation, miRNAs, and histones) that can actually be implemented into clinical practice.

Diagnostic Assessment of septin9 DNA Methylation for Colorectal Cancer Using Blood Detection: A Meta-Analysis

This meta-analysis aimed to assess the diagnostic efficiency of blood-based septin 9 (SEPT9) methylation assay for the detection of colorectal cancer (CRC). Studies were searched in the Springer, Wiley, Cochrane Library, PubMed, Ovid, Embase, Web of Science, China BioMedicine, Wanfang and China National Knowledge Infrastructure databases until July 2017. Methodological quality assessment was performed based on the guidelines of the Quality Assessment of Diagnostic Accuracy Studies. According to 1/3 and 2/3 algorithms, the meta-analyses for the diagnostic effect of SEPT9 in CRC were compared with healthy subjects and subjects with polyps, adenoma, and non-CRC, respectively. The random effects model was applied and publication bias was evaluated. The included 29 studies comprised 10,486 subjects (3202 patients with CRC and 7284 controls). In comparison with healthy subjects, the pooled sensitivity with 95% confidence intervals (CIs) of SEPT9 methylation for the diagnosis of CRC was 0.74 (95% CI: 0.61-0.84) in the 1/3 algorithm group, whereas the specificity was 0.96 (95% CI: 0.95-0.97) in the 2/3 algorithm group. Additionally, positive likelihood ratio was less than 10 and negative likelihood ratio more than 0.1 in the 2/3 algorithm group for patients with CRC vs. polyps and adenoma. The P value of Deeks' funnel plot was 0.36, suggesting that there was no publication bias. SEPT9 methylation can be used to diagnose CRC in healthy individuals under the 2/3 algorithm. The determination of SEPT9 methylation does not distinguish well between CRC and polyps or adenoma.

Biomarker discovery study of inflammatory proteins for colorectal cancer early detection demonstrated importance of screening setting validation

OBJECTIVES

Most studies identifying inflammatory markers for early detection of colorectal cancer (CRC) were conducted using clinically manifest cases. We aimed to identify circulating inflammatory biomarkers for early detection of CRC and validate them in both a clinical setting and a true screening setting.

STUDY DESIGN AND SETTING

A total of 92 inflammatory proteins were quantified in baseline plasma samples from individuals clinically diagnosed with CRC and neoplasm-free controls matched on age and sex (training set). A multimarker panel was selected and evaluated in samples from another clinical setting (validation set C) and a screening setting (validation set S).

RESULTS

In the training set (N = 330), a five-biomarker signature was selected that provided an area under curve (AUC) of 0.85 and 60.9% sensitivity to detect CRC at 90% specificity. When this algorithm was applied to validation set C (N = 318), the AUC (0.80) and sensitivity (49.5%) at 90% specificity for CRC diagnosis were only slightly lower than those in the training set. By contrast, the diagnostic performance of the algorithm in validation set S (N = 126) from a true screening setting was much poorer, with an AUC of 0.59 and a sensitivity of 28.6% at 90% specificity.

CONCLUSIONS

An inflammation-related protein panel with apparently good diagnostic properties for CRC detection was identified and confirmed in an independent clinical validation set. However, the biomarker combination performed substantially worse in a validation sample from a true screening setting. Our results underline the importance of validation in screening settings subsequently to novel signature discovery for cancer early detection.

Diagnostic Value of Methylated Septin9 for Colorectal Cancer Detection

Background

Methylated Septin9 (mSEPT9) has been suggested as a reliable biomarker in colorectal cancer (CRC) detection. We aimed to determine the diagnostic value of mSEPT9 for CRC detection in Chinese patients. In addition, we compared the diagnostic efficacy of mSEPT9 to traditional screening method [fecal occult blood test (FOBT)] and two biomarkers [carcinoembryonic antigen (CEA) and carbohydrate antigen-199 (Ca-199)].

Methods

Overall 248 subjects including 123 patients with CRC and 125 controls were included. Plasma and fecal samples were collected for CEA, Ca-199, mSEPT9, and FOBT tests. Sensitivity and specificity were calculated to evaluate the diagnostic efficacy of each method; receiver operating characteristic (ROC) curve was plotted for the assessment of diagnostic accuracy, and comparisons among FOBT, mSEPT9, and the combination were assessed through area under the ROC curve (AUC).

Results

mSEPT9 achieved overall sensitivity and specificity of 61.8% [95% confidence interval (CI): 53.0–69.9%] and 89.6% (83.0–93.8%), respectively, with an AUC value of 0.757 (95% CI: 0.701–0.807), superior to FOBT [sensitivity: 61.4% (50.9–70.9%); specificity: 70.3% (59.1–79.5%); AUC: 0.658 (0.578–0.723)], CEA [sensitivity: 35.0% (27.1–43.7%); specificity: 62.6% (53.8–70.7%); AUC: 0.485 (0.411–0.559)], and Ca-199 [sensitivity: 17.9% (12.1–25.6%); specificity: 55.7% (48.9–64.1%); AUC: 0.353 (0.283–0.423)]. The combination of mSEPT9 and FOBT further improved sensitivity and AUC value of 84.1% (75.1–90.3%) and 0.807 (0.752–0.863), respectively, while specificity was declined to 62.2% (50.8–72.4%).

Conclusion

mSEPT9 demonstrated best diagnostic ability in CRC detection compared with FOBT, CEA, and Ca-199. The combination of mSEPT9 and FOBT further improved diagnostic sensitivity especially for early stage disease, which may provide a new approach for future CRC screening, though further investigations are warranted.

Epigenomic biomarkers for prognostication and diagnosis of gastrointestinal cancers

Altered epigenetic regulation is central to many human diseases, including cancer. Over the past two decade, major advances have been made in our understanding of the role of epigenetic alterations in carcinogenesis, particularly for DNA methylation, histone modifications and non-coding RNAs. Aberrant hypermethylation of DNA at CpG islands is a well-established phenomenon that mediates transcriptional silencing of tumor suppressor genes, and it is an early event integral to gastrointestinal cancer development. As such, detection of aberrant DNA methylation is being developed as biomarkers for prognostic and diagnostic purposes in gastrointestinal cancers. Diverse tissue types are suitable for the analyses of methylated DNA, such as tumor tissues, blood, plasma, and stool, and some of these markers are already utilized in the clinical setting. Recent advances in the genome-wide epigenomic approaches are enabling the comprehensive mapping of the cancer methylome, thus providing new avenues for mining novel biomarkers for disease prognosis and diagnosis. Here, we review the current knowledge on DNA methylation biomarkers for the prognostication and non-invasive diagnosis of gastrointestinal cancers and highlight their clinical application.

Review of Blood-Based Colorectal Cancer Screening: How Far Are Circulating Cell-Free DNA Methylation Markers From Clinical Implementation?

Colorectal cancer (CRC) is a leading cause of cancer related deaths worldwide, and late stages (III-IV) in particular have low 5-year survival rates. Stage shifting by CRC screening programs has proven effective by decreasing morbidity and mortality and in many countries national CRC screening programs have been implemented. Currently, European, Asian, and American authorities recommend screening for CRC using fecal occult blood testing, sigmoidoscopy, or colonoscopy. Because these approaches all have weaknesses (eg, poor compliance, high costs, test invasiveness), much effort has been put into the development of alternative screening approaches, many of which are blood-based. Blood-based strategies especially present the advantages of minimally invasiveness compared to endoscopies and an expectantly higher compliance rate compared to stool-based tests. The last decades have seen many discovery studies identifying promising blood-based biomarkers of CRC; however, common to all of these markers is that their clinical usefulness remains evasive. At present only one blood-based CRC screening marker has been approved in the United States. The aim of this review is to discuss the development of blood-based cell-free DNA methylation marker candidates for CRC screening. On the basis of a methodical literature search, the past, present, and future of cell-free DNA screening markers for CRC are revised and discussed. Resource limitations and technical challenges related to sensitivity and specificity measurements keep many markers at bay. Possible solutions to these problems are offered to enable markers to benefit future screening participants.

The prognostic efficacy of cell-free DNA hypermethylation in colorectal cancer

Epigenetic alterations in colorectal cancer (CRC) cause important differences in the underlying tumor biology and aggressiveness. DNA hypermethylation is central for the development of CRC but the prognostic impact remains elusive. We aimed to assess the association between cell-free hypermethylated DNA and stage and survival in colorectal cancer (CRC). We analyzed pre-treatment plasma samples from 193 patients with CRC. Thirty gene-promoter regions were analyzed using methylation specific PCR. We compared the median number (range) of hypermethylated promoter regions with CRC stage, and constructed a multivariable Cox-regression model adjusted for stage, to evaluate the added prognostic information. The median number of hypermethylated promoter regions was nine (0-28) in patients with distant metastasis compared to five (0-19) in patients without metastatic disease (p < 0.0001). The majority of the hypermethylated promoter regions inferred a poor prognosis. Cox-regression analysis adjusted for patient age, sex, pre-treatment CEA-levels, and disease stage, showed that RARB (HR = 1.99, 95% CI [1.07, 3.72]) and RASSF1A (HR = 3.35, 95% CI [1.76, 6.38]) hypermethylation inferred a significant effect on survival. The risk of metastasis increase with the number of cell-free hypermethylated promoter regions. The presence of RARB and RASSF1A hypermethylation indicated aggressive disease, regardless of stage at the time of diagnosis.

Advance in plasma SEPT9 gene methylation assay for colorectal cancer early detection

This review article summarizes the research advances of the plasma-based SEPT9 gene methylation assay for the clinical detection of colorectal cancer and its limitations. Colorectal cancer is a common malignancy with a poor prognosis and a high mortality, for which early detection and diagnosis are particularly crucial for the high-risk groups. Increasing evidence supported that SEPT9 gene methylation is associated with the pathogenesis of colorectal cancer and that detecting the level of methylation of SEPT9 in the peripheral blood can be used for screening of colorectal cancer in susceptible populations. In recent years, the data obtained in clinical studies demonstrated that the SEPT9 gene methylation assay has a good diagnostic performance with regard to both sensitivity and specificity with the advantage of better acceptability, convenience and compliance with serological testing compared with fecal occult blood tests and carcinoembryonic antigen for colorectal cancer (CRC). Furthermore, the combination of multiple methods or markers has become a growing trend for CRC detection and screening. Nevertheless, the clinical availability of the methylated SEPT9 assay is still limited because of the large degree of sample heterogeneity caused by demographic characteristics, pathological features, comorbidities and/or technique selection. Another factor is the cost-effectiveness of colorectal cancer screening strategies that hinders its large-scale application. In addition, improvements in its accuracy in detecting adenomas and premalignant polyps are required.

Circulating cell-free nucleosomes as biomarkers for early detection of colorectal cancer

The aim was to evaluate serum levels of circulating cell-free nucleosomes (ccfn) containing a variety of epigenetic signals including 5-methylcytosine DNA, histone modifications H3K9Me3, H3K9Ac, H3S10PO4, H3K36Me3, H4K20Me3, H4PanAc and pH2AX, nucleosome variant H2AZ and nucleosome adducts with HMGB1 and EZH2 as well as ccfn per se, in addition to develop and evaluate predictor models based on the above mentioned ccfn and including serum levels of carcinoembryonic antigen (CEA), in early detection of colorectal cancer (CRC). Blood-samples were collected from 4,105 individuals undergoing colonoscopy. Serum levels of ccfn and CEA were determined using enzyme-linked immunosorbent assays platforms. Individual assessment of levels of ccfn showed area under the receiver operating characteristic curve (AUCROC) = 0.525-0.576 in discrimination of individuals with CRC from individuals with non-malignant findings. Predictor models including ccfn containing 5-methylcytosine DNA, CEA, age and gender improved results (AUCROC = 0.736, sensitivity = 0.37 at specificity = 0.90). Further improvement was achieved in discrimination of individuals with CRC from individuals with clean colorectum (AUCROC = 0.840, sensitivity = 0.57 at specificity = 0.90). The levels of ccfn among patients with CRC appeared to be stage-independent. In conclusion, the performance of the developed predictor models is potentially promising in early detection of CRC.

A pooled analysis of the diagnostic efficacy of plasmic methylated septin-9 as a novel biomarker for colorectal cancer

The methylation status of septin-9 gene in plasma has been developed as a promising biomarker to aid in the diagnosis of colorectal cancer (CRC). In this study, we aimed to evaluate the overall diagnostic ability of septin-9 methylation for detection of CRC. Studies on the diagnostic performance of plasma septin-9 in CRC were searched from the online databases up to January 31st, 2017. Risk of bias among the studies was estimated according to the Quality Assessment of Studies of Diagnostic Accuracy included in the Systematic Reviews (QUADAS) II checklist. The aggregation of the effect sizes was enabled by utilizing a bivariate analysis model. A meta-regression test and influence analysis were conducted to determine the underlying sources of heterogeneity. According to the predefined criteria, 1,462 patients with CRC from 14 eligible trials were included. The quantitative meta-analyses showed that methylated septin-9 in plasma sustained a pooled sensitivity of 0.67 (95% CI, 0.61-0.73) and specificity of 0.89 (95% CI, 0.86-0.92) in discriminating CRC patients from cancer-free individuals, along with an area under the curve of 0.87. Moreover, the stratified analyses grouped by ethnicity demonstrated that methylayted septin-9 testing achieved a better sensitivity of 0.72 (95% CI, 0.68-0.76) in the European-based population group and a higher specificity of 0.90 (95% CI, 0.88-0.92) in the Asian-based population group. Plasmic methylated septin-9 suggests a promising diagnostic efficacy in confirming CRC. However, more studies are required to confirm our findings.

Detection of colorectal neoplasia: Combination of eight blood-based, cancer-associated protein biomarkers

Serological biomarkers may be an option for early detection of colorectal cancer (CRC). The present study assessed eight cancer-associated protein biomarkers in plasma from subjects undergoing first time ever colonoscopy due to symptoms attributable to colorectal neoplasia. Plasma AFP, CA19-9, CEA, hs-CRP, CyFra21-1, Ferritin, Galectin-3 and TIMP-1 were determined in EDTA-plasma using the Abbott ARCHITECT® automated immunoassay platform. Primary endpoints were detection of (i) CRC and high-risk adenoma and (ii) CRC. Logistic regression was performed. Final reduced models were constructed selecting the four biomarkers with the highest likelihood scores. Subjects (N = 4,698) were consecutively included during 2010-2012. Colonoscopy detected 512 CRC patients, 319 colonic cancer and 193 rectal cancer. Extra colonic malignancies were detected in 177 patients, 689 had adenomas of which 399 were high-risk, 1,342 had nonneoplastic bowell disease and 1,978 subjects had 'clean' colorectum. Univariable analysis demonstrated that all biomarkers were statistically significant. Multivariate logistic regression demonstrated that the blood-based biomarkers in combination significantly predicted the endpoints. The reduced model resulted in the selection of CEA, hs-CRP, CyFra21-1 and Ferritin for the two endpoints; AUCs were 0.76 and 0.84, respectively. The postive predictive value at 90% sensitivity was 25% for endpoint 1 and the negative predictive value was 93%. For endpoint 2, the postive predictive value was 18% and the negative predictive value was 97%. Combinations of serological protein biomarkers provided a significant identification of subjects with high risk of the presence of colorectal neoplasia. The present set of biomarkers could become important adjunct in early detection of CRC.

The performance of the SEPT9 gene methylation assay and a comparison with other CRC screening tests: A meta-analysis

The SEPT9 gene methylation assay is the first FDA-approved blood assay for colorectal cancer (CRC) screening. Fecal immunochemical test (FIT), FIT-DNA test and CEA assay are also in vitro diagnostic (IVD) tests used in CRC screening. This meta-analysis aims to review the SEPT9 assay performance and compare it with other IVD CRC screening tests. By searching the Ovid MEDLINE, EMBASE, CBMdisc and CJFD database, 25 out of 180 studies were identified to report the SEPT9 assay performance. 2613 CRC cases and 6030 controls were included, and sensitivity and specificity were used to evaluate its performance at various algorithms. 1/3 algorithm exhibited the best sensitivity while 2/3 and 1/1 algorithm exhibited the best balance between sensitivity and specificity. The performance of the blood SEPT9 assay is superior to that of the serum protein markers and the FIT test in symptomatic population, while appeared to be less potent than FIT and FIT-DNA tests in asymptomatic population. In conclusion, 1/3 algorithm is recommended for CRC screening, and 2/3 or 1/1 algorithms are suitable for early detection for diagnostic purpose. The SEPT9 assay exhibited better performance in symptomatic population than in asymptomatic population.

Comparative analysis of 12 different kits for bisulfite conversion of circulating cell-free DNA

Blood circulating cell-free DNA (cfDNA) is becoming popular in the search of promising predictive and prognostic biomarkers. Among these biomarkers, cfDNA methylation markers have especially gained considerable attention. A significant challenge in the utilization of cfDNA methylation markers is the limited amount of cfDNA available for analyses; reportedly, bisulfite conversion (BSC) reduce cfDNA amounts even further. Nevertheless, few efforts have focused on ensuring high cfDNA conversion efficiency and recovery after BSC. To compare cfDNA recovery of different BSC methods, we compared 12 different commercially available BSC kits. We tested whether DNA recovery was affected by the molecular weight and/or quantity of input DNA. We also tested BSC efficiency for each kit. We found that recovery varied for DNA fragments of different lengths: certain kits recovered short fragments better than others, and only 3 kits recovered DNA fragments of <100 bp well. In contrast, DNA input amount did not seem to affect DNA recovery: for quantities spanning between 820 and ∼25,000 genome equivalents per BSC, a linear relation was found between input and recovery amount. Overall, mean recovery ranged between 9 and 32%, with BSC efficiency of 97-99.9%. When plasma cfDNA was used as input for BSC, recovery varied from 22% for the poorest and 66% for the best performing kits, while conversion efficiency ranged from 96 to 100% among different kits. In conclusion, clear performance differences exist between commercially available BSC kits, both in terms of DNA recovery and conversion efficiency. The choice of BSC kit can substantially impact the amount of converted cfDNA available for downstream analysis, which is critical in a cfDNA methylation marker setting.

2017 update on the relationship between diabetes and colorectal cancer: epidemiology, potential molecular mechanisms and therapeutic implications

Worldwide deaths from diabetes mellitus (DM) and colorectal cancer increased by 90% and 57%, respectively, over the past 20 years. The risk of colorectal cancer was estimated to be 27% higher in patients with type 2 DM than in non-diabetic controls. However, there are potential confounders, information from lower income countries is scarce, across the globe there is no correlation between DM prevalence and colorectal cancer incidence and the association has evolved over time, suggesting the impact of additional environmental factors. The clinical relevance of these associations depends on understanding the mechanism involved. Although evidence is limited, insulin use has been associated with increased and metformin with decreased incidence of colorectal cancer. In addition, colorectal cancer shares some cellular and molecular pathways with diabetes target organ damage, exemplified by diabetic kidney disease. These include epithelial cell injury, activation of inflammation and Wnt/β-catenin pathways and iron homeostasis defects, among others. Indeed, some drugs have undergone clinical trials for both cancer and diabetic kidney disease. Genome-wide association studies have identified diabetes-associated genes (e.g. TCF7L2) that may also contribute to colorectal cancer. We review the epidemiological evidence, potential pathophysiological mechanisms and therapeutic implications of the association between DM and colorectal cancer. Further studies should clarify the worldwide association between DM and colorectal cancer, strengthen the biological plausibility of a cause-and-effect relationship through characterization of the molecular pathways involved, search for specific molecular signatures of colorectal cancer under diabetic conditions, and eventually explore DM-specific strategies to prevent or treat colorectal cancer.

The performance of the mSEPT9 assay is influenced by algorithm, cancer stage and age, but not sex and cancer location

PURPOSE

This study aims to examine the influence of algorithm and subject-related factors, including cancer stage, age, sex, and cancer location, on the performance of the SEPT9 gene methylation test, an assay approved by the US FDA for colorectal cancer (CRC) screening.

METHODS

A total of 1225 subjects were recruited in this opportunistic screening study, including 388 CRC patients, 139 subjects with adenoma, 108 subjects with hyperplastic polyps, and 590 subjects with no evidence of disease (NED). Epi proColon 2.0 CE assay was used to examine the blood level of SEPT9 gene methylation.

RESULTS

It was found that tests using 1/3 algorithm exhibited higher detection rate than those using the 2/3 algorithm for CRC, adenoma, hyperplastic polyps, while the false positive rate in subjects with NED was also higher with 1/3 algorithm. The positive detection rate (PDR) of the assay for stage 0 and I CRC were lower than later stages (Stage II, III and IV). Interestingly, the normal subjects above 60 years old exhibited significantly higher PDR than subjects from younger groups, while no significant change in PDR was observed among age groups in CRC patients. Furthermore, no difference in the PDR for CRC was found between male and female, and the PDR for CRC at various colorectal locations were essentially identical.

CONCLUSIONS

Algorithm, cancer stage and age are factors affecting the detection rate of the SEPT9 assay, while sex and cancer location appeared to have no influence on its performance.

Diagnostic Accuracy of Methylated SEPT9 for Blood-based Colorectal Cancer Detection: A Systematic Review and Meta-Analysis

Objectives:

More convenient and effective blood-based methods are believed to increase colorectal cancer (CRC) detection adoption. The effectiveness of methylated SPET9 for CRC detection has been reviewed in the newly published recommendation statement by US Preventive Services Task Force (USPSTF), while detailed instructions were not provided, which may be a result of insufficient evidence. Therefore, more evidence is needed to assist practitioners to thoroughly understand the utilization of this special maker.

Methods:

Based on the standard method, a systematic review and meta-analysis was performed. Quadas-2 was used to assess the methodological quality of studies. Relevant studies were searched and screened from PubMed, Embase and other literature databases up to June 1, 2016. Pooled sensitivity, specificity and diagnostic odds ratio were summarized by bivariate mixed effect model and area under the curve (AUC) was estimated by hierarchical summary receiver operator characteristic curve.

Results:

25 studies were included for analysis. The pooled sensitivity, specificity and AUC were 0.71, 0.92 and 0.88, respectively. Among the various methods and assays, Epipro Colon 2.0 with 2/3 algorithm was the most effective in colorectal cancer detection. Positive ratio of mSEPT9 was higher in advanced CRC (45% in I, 70% in II, 76% in III, 79% in IV) and lower differentiation (31% in high, 73% in moderate, 90% in low) tissue. However, this marker has poor ability of identifying precancerous lesions according to current evidence.

Conclusions:

mSEPT9 is a reliable blood-based marker in CRC detection, particularly advanced CRC. Epipro Colon 2.0 with 2/3 algorithm is currently the optimal method and assay to detect CRC.

The Relationship between the Methylated Septin-9 DNA Blood Test and Stool Occult Blood Test for Diagnosing Colorectal Cancer in Taiwanese People

BACKGROUND

Colorectal cancer (CRC) is a common and lethal disease in the world. There is an increasing number of cases in Taiwan and a higher rate at advanced stages. The immune fecal occult blood test (iFOBT) has been used as a screening method in Taiwan for years. A new novel diagnostic tool, the Methylated Septin-9 (MS-9) DNA blood test, had been reported to have high sensitivity and specificity for CRC detection. There are no available data in Taiwan, so we conducted this prospective randomized trial to investigate the relationship among the MS-9 DNA blood test, iFOBT, and a combination of the two tests for diagnosing CRC in Taiwanese people.

METHODS

From July 1, 2012 to December 31, 2013, we prospectively selected 60 plasma samples from patients who were diagnosed with CRC and otherwise, the healthy group by colonoscopy in our hospital. Patients were divided into the CRC group and healthy group. CRC stages 0, I, II and stages III and IV were separately analyzed. We calculated the sensitivity and specificity of each group to determine the relationship among the MS-9 DNA blood test, iFOBT, and a combination of the two tests for diagnosing CRC in Taiwanese people.

RESULTS

The results of the MS-9 DNA blood test for the 60 samples were divided into three groups, and the sensitivity as well as the specificity of the MS-9 DNA blood test to detect CRC were 47% and 89%, respectively. The results of iFOBT were also divided into three groups, and had higher sensitivity (84%) but lower specificity (55%) using iFOBT to detect CRC. Higher rates could be predicted to detect CRC if both the tests were positive.

CONCLUSIONS

A combined MS-9 DNA blood test and iFOBT may help in a higher detection rate of CRC. It could be offered to individuals who are unwilling or unable to undergo colonoscopy. Further large prospective, randomized studies are needed in the future.

SEPT9 and SHOX2 DNA methylation status and its utility in the diagnosis of colonic adenomas and colorectal adenocarcinomas

Background

Colorectal cancer (CRC) appear to arise from precursor lesions in a well-characterized adenoma-carcinoma sequence. Significant efforts have been invested to develop biomarkers that identify early adenocarcinomas and adenomas with high-grade dysplasia, since these are believed to harbor a particularly high risk for malignant transition and thus require resection. Promoter methylation of SEPT9 and SHOX2 has been suggested as a biomarker for various solid malignant tumors. Hence, the present study aimed to test their biomarker potential in CRC and precursor lesions.

Results

Assessment of promoter methylation of SEPT9 distinguished adenomas and CRC from controls as well as advanced from non-advanced adenomas (all p < 0.001). Correspondingly, SHOX2 methylation levels in adenomas and colorectal carcinomas were significantly higher compared to those in normal control tissues (p < 0.001). Histologic transition from adenomas to CRC was paralleled by amplification of the SEPT9 gene locus.

Conclusions

SEPT9/SHOX2 methylation assays may help to distinguish colorectal cancer and adenomas from normal and inflammatory colonic tissue, as well as advanced from non-advanced adenomas. Further studies need to validate these findings before introduction in clinical routine.

Discovery and Validation of Hypermethylated Markers for Colorectal Cancer

Colorectal carcinoma (CRC) is one of the most prevalent malignant tumors worldwide. Screening and early diagnosis are critical for the clinical management of this disease. DNA methylation changes have been regarded as promising biomarkers for CRC diagnosis. Here, we map DNA methylation profiling on CRC in six CRCs and paired normal samples using a 450 K bead array. Further analysis confirms the methylation status of candidates in two data sets from the Gene Expression Omnibus. Receiver operating characteristic (ROC) curves are calculated to determine the diagnostic performances. We identify 1549 differentially methylated regions (DMRs) showing differences in methylation between CRC and normal tissue. Two genes (ADD2 and AKR1B1), related to the DMRs, are selected for further validation. ROC curves show that the areas under the curves of ADD2 and AKR1B1 are higher than that of SEPT9, which has been clinically used as a screening biomarker of CRC. Our data suggests that aberrant DNA methylation of ADD2 and AKR1B1 could be potential screening markers of CRC.