A Biomarker Panel to Detect Synchronous Neoplasm in Non-neoplastic Surveillance Biopsies from Patients with Ulcerative Colitis

High Expression of IRS-1, RUNX3 and SMAD4 Are Positive Prognostic Factors in Stage I-III Colon Cancer

Colon cancer is a common malignancy and a major contributor to human morbidity and mortality. In this study, we explore the expression and prognostic impact of IRS-1, IRS-2, RUNx3, and SMAD4 in colon cancer. Furthermore, we elucidate their correlations with miRs 126, 17-5p, and 20a-5p, which are identified as potential regulators of these proteins. Tumor tissue from 452 patients operated for stage I-III colon cancer was retrospectively collected and assembled into tissue microarrays. Biomarkers' expressions were examined by immunohistochemistry and analyzed using digital pathology. In univariate analyses, high expression levels of IRS1 in stromal cytoplasm, RUNX3 in tumor (nucleus and cytoplasm) and stroma (nucleus and cytoplasm), and SMAD4 in tumor (nucleus and cytoplasm) and stromal cytoplasm were related to increased disease-specific survival (DSS). In multivariate analyses, high expression of IRS1 in stromal cytoplasm, RUNX3 in tumor nucleus and stromal cytoplasm, and high expression of SMAD4 in tumor and stromal cytoplasm remained independent predictors of improved DSS. Surprisingly, with the exception of weak correlations (0.2 < r < 0.25) between miR-126 and SMAD4, the investigated markers were mostly uncorrelated with the miRs. However, weak to moderate/strong correlations (0.3 < r < 0.6) were observed between CD3 and CD8 positive lymphocyte density and stromal RUNX3 expression. High expression levels of IRS1, RUNX3, and SMAD4 are positive prognostic factors in stage I-III colon cancer. Furthermore, stromal expression of RUNX3 is associated with increased lymphocyte density, suggesting that RUNX3 is an important mediator during recruitment and activation of immune cells in colon cancer.

Molecular characterization of ulcerative colitis-associated colorectal carcinomas

Patients with ulcerative colitis (UC) are at increased risk for developing colorectal cancer (CRC). In contrast to sporadic colorectal tumorigenesis, TP53 mutations occur early in the progression from inflamed colonic epithelium to dysplasia to CRC, and are sometimes readily detectable in inflamed, (yet) non-dysplastic mucosa. Here, we analyzed formalin-fixed paraffin-embedded tissue samples from 19 patients with long-standing UC (median 18 years, range 3 to 34) who had developed CRC as a consequence of chronic inflammation of the large bowel. We performed microsatellite instability testing, copy number analysis by array-based comparative genomic hybridization, mutation analysis by targeted next generation sequencing (48-gene panel) and TP53 immunostaining. The results were compared to The Cancer Genome Atlas (TCGA) data on sporadic CRC. All UC-CRC lesions in our cohort were microsatellite stable. Overall, genomic imbalances of UC-CRCs showed patterns of chromosomal aneuploidies characteristic for sporadic CRC with the exception of gains of chromosome arm 5p (12 of 23 UC-CRC, 52%), which are rare in sporadic CRCs from TCGA (21 of 144, 15%; FDR adjusted P = 0.006). UC-CRCs showed a predilection for TP53 alterations, which was the most frequently mutated gene in our cohort (20 of 23, 87%). Interestingly, spatially separated tumor lesions from individual patients tended to harbor distinct TP53 mutations. Similar to CRCs arising in a background of Crohn's colitis, the genetic landscape of UC-CRCs was characterized by TP53 mutations and chromosomal aneuploidies including gains of chromosome arm 5p. Both alterations harbor the potential for early detection in precursor lesions, thus complementing morphologic diagnosis.

Status of Gene Methylation and Polymorphism in Different Courses of Ulcerative Colitis and Their Comparison with Sporadic Colorectal Cancer

BACKGROUND

The objective of this study is to explore the common genetic and epigenetic mechanism of ulcerative colitis (UC) and sporadic colorectal cancer (SCRC) by observing genes methylation level and single nucleotide polymorphisms (SNPs) of different disease courses in UC and SCRC.

METHODS

Two hundred subjects were enrolled, including 40 in the healthy control (HC) group, 50 in the short disease course UC group (SUC), 52 in the long disease course UC group (LUC), and 58 in the SCRC group. Methylation-specific polymerase chain reaction was used to detect the methylation of MINT1 and cyclooxygenase 2 (COX-2) gene. Single nucleotide polymorphisms of interleukin (IL)-23R rs10889677 and IL-1β rs1143627 were detected by Sanger sequencing.

RESULTS

Compared with HCs (32.5%), methylation level of MINT1 was significantly increased in SCRC (67.2%; P = 0.001) and was a risk factor for CRC (odds ratio, [OR] 4.26). The methylation ratios of COX-2 were 95.0%, 58.0%, 23.1%, and 24.1% in HC, SUC, LUC, and SCRC, respectively, which were negatively correlated with the disease course of UC (r = -0.290). Hypermethylation of COX-2 was a protective factor for SUC (OR, 0.11), LUC (OR, 0.02), and SCRC (OR, 0.03; P < 0.05). Compared with HCs, rs10889677 allele A was a risk factor for SUC and LUC, and rs1143627 allele T was a protective factor for SUC and LUC. Genotype TT was a protective factor for SUC.

CONCLUSION

The hypomethylation of COX-2 gene was a common risk factor and epigenetic modification for UC and SCRC, which might be one of the mechanisms through which UC patients were susceptible to CRC. The hypermethylation of MINT1 was a risk factor for SCRC but not for UC; alleles of IL-23Rrs10889677 and IL-1βrs1143627 were related to UC but not to SCRC.

Biomarkers for Early Detection of Colitis-associated Colorectal Cancer - Current Concepts, Future Trends

Colitis-associated colorectal cancer (CAC) remains a critical complication of ulcerative colitis (UC) with a mortality of approximately 15%, which makes early CAC diagnosis crucial. The current standard of surveillance, with repetitive colonoscopies and histological testing of biopsied mucosa samples, is burdensome and expensive, and therefore less invasive methods and reliable biomarkers are needed. Significant progress has been made, thanks to continuous extensive research in this field, however, no clinically relevant biomarker has been established so far. This review of the current literature presents the genetic and molecular differences between CAC and sporadic colorectal cancer and covers progress made in the early detection of CAC carcinogenesis. It focuses on biomarkers under development, which can easily be tested in samples of body fluids or breath and, once made clinically available, will help to differentiate between progressors (UC patients who will develop dysplasia) from non-progressors and enable early intervention to decrease the risk of cancer development.

Single Nucleotide Polymorphisms in Colitis-Associated Colorectal Cancer: A Current Overview with Emphasis on the Role of the Associated Genes Products

Colitis-Associated Colorectal Cancer (CA-CRC) is one of the most severe complications of Inflammatory Bowel Disease (IBD) and constitutes the cause of death in 10-15% of patients. The risk ratio for carcinogenesis depends on numerous factors, such as the extent of intestinal inflammatory lesions and the duration of the disease. CA-CRC is a major problem of today's gastroenterology and colorectal surgery due to the fact that the incidence and prevalence of IBD are increasing. In this review, we discussed the current state of knowledge regarding genetic differences between sporadic CRC and CA-CRC, especially pertaining to the chromosomal instability mechanism (CIN). In order to explain CA-CRC molecular basis, we have analyzed the data from studies regarding the correlations between CA-CRC and the presence of Single Nucleotide Polymorphisms (SNPs). Further focus on the role of associated proteins has emphasized the role of NF-κB signaling as the main link between inflammation and carcinogenesis during the course of IBD.

From Genetics to Epigenetics, Roles of Epigenetics in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD) is a destructive, recurrent, and heterogeneous disease. Its detailed pathogenesis is still unclear, although available evidence supports that IBD is caused by a complex interplay between genetic predispositions, environmental factors, and aberrant immune responses. Recent breakthroughs with regard to its genetics have offered valuable insights into the sophisticated genetic basis, but the identified genetic factors only explain a small part of overall disease variance. It is becoming increasingly apparent that epigenetic factors can mediate the interaction between genetics and environment, and play a fundamental role in the pathogenesis of IBD. This review outlines recent genetic and epigenetic discoveries in IBD, with a focus on the roles of epigenetics in disease susceptibility, activity, behavior and colorectal cancer (CRC), and their potential translational applications.

Thrombocytopenia in solid tumors: Prognostic significance

Solid tumors are a heterogeneous group of malignancies that result from out-of-control proliferation of cells. Thrombocytopenia is a common complication among patients with solid tumors that predispose them to bleeding disorders. The aim of this review article is to investigate the underlying mechanisms of the risk and incidence of thrombocytopenia in solid tumors. It can be argued that thrombocytopenia is a poor prognostic factor in solid tumors that can result from several factors such as polymorphism and mutation in some transcription factors and cytokines involved in megakaryocytic maturation or from the adverse effects of treatment. Therefore, an understanding of the exact mechanism of thrombocytopenia pathogenesis in each stage of solid tumors can help in developing therapeutic strategies to decrease bleeding complications in these malignancies.

New Methylation Biomarker Panel for Early Diagnosis of Dysplasia or Cancer in High-Risk Inflammatory Bowel Disease Patients

BACKGROUND

The risk of developing colorectal cancer (CRC) is increased in patients with inflammatory bowel disease (IBD) of the colon. The aim of the study was to evaluate the effectiveness of selected methylation gene panel for the early detection of CRC in high-risk IBD patients.

METHODS

In a discovery phase, 73 biopsies of 48 IBD patients (associated or not to CRC) were analyzed from genome-wide DNA methylation analysis using the Illumina Human Methylation 450K BeadChip. The panel of 5 genes selected (EYA4, SLIT2, FLI1, USP44, and SND1) was validated prospectively using methylation-specific melting curve analysis in biopsies of diseased and adjacent healthy tissue of 203 patients: 38 with IBD and associated neoplasia, 81 patients with IBD (25 of them with high risk), 48 with sporadic CRC, and 36 healthy controls.

RESULTS

The prevalence of methylation was higher in patients with IBD and associated neoplasia (both in diseased and adjacent healthy tissue, 71% and 52%, respectively) than in healthy controls (2/36, 6%; P = 6.72E-05). Methylation in IBD patients at high risk of dysplasia or cancer was more frequently detected than in patients at low risk (92% vs 57%; odds ratio, 8.63; P = 0.001). EYA4 and SLIT2 were the markers most frequently methylated. Differences in methylation levels were more evident in healthy mucosa (82% vs 15% high vs low risk, respectively; P = 1.25E-05).

CONCLUSIONS

Analysis of this panel of methylation markers may help in the early identification of colorectal dysplasia or cancer in high-risk IBD patients.

Precancer in ulcerative colitis: the role of the field effect and its clinical implications

Cumulative evidence indicates that a significant proportion of cancer evolution may occur before the development of histological abnormalities. While recent improvements in DNA sequencing technology have begun to reveal the presence of these early preneoplastic clones, the concept of 'premalignant field' was already introduced by Slaughter more than half a century ago. Also referred to as 'field effect', 'field defect' or 'field cancerization', these terms describe the phenomenon by which molecular alterations develop in normal-appearing tissue and expand to form premalignant patches with the potential to progress to dysplasia and cancer. Field effects have been well-characterized in ulcerative colitis, an inflammatory bowel disease that increases the risk of colorectal cancer. The study of the molecular alterations that define these fields is informative of mechanisms of tumor initiation and progression and has provided potential targets for early cancer detection. Herein, we summarize the current knowledge about the molecular alterations that comprise the field effect in ulcerative colitis and the clinical utility of these fields for cancer screening and prevention.

Integrated strategy of differentially expressed genes associated with ulcerative colitis

Ulcerative colitis (UC) is a chronic inflammatory bowel disease that is associated with both genetic and environmental factors; however, the underlying pathogenesis of UC remains unclear. The present study aimed to further explore 12 microarray datasets from patients with UC obtained from the Gene Expression Omnibus repository, for potential genetic pathogenesis of UC through a global bioinformatics view, which included identification of differentially expressed genes (DEGs), functional enrichments, protein-protein interactions, transcriptional and post-transcriptional regulation and drug-gene associations. This integrated analysis screened 233 DEGs that were compared between UC and normal control tissue samples; these included 173 upregulated and 60 downregulated DEGs. Subsequently, transcription factors, such as TATA-binding protein 1 (TBP1; hsa_TATAAA_V$TATA_01) and nuclear factor-κB (NF-κB; hsa_V$NFKAPPAB_01) and microRNAs (miRNAs; such as miR-516-3p and miR-23a) were revealed to be associated with 233 DEGs. Notably, further analysis indicated that these DEGs were enriched in certain diseases, including inflammation, fibrosis and immune system diseases, and were also associated with some drugs, including prednisone, collagenase and mycophenolate mofetil, which may provide choice for treatment of UC. In conclusion, this study may provide novel insights into discovering potential molecular targets involved in the pathogenesis and treatment of UC.

Associations between single-nucleotide polymorphisms and inflammatory bowel disease-associated colorectal cancers in inflammatory bowel disease patients: a meta-analysis

PURPOSE

To assess the correlation between single-nucleotide polymorphisms (SNPs) and inflammatory bowel disease (IBD)-associated colorectal cancer (CRC) in IBD patients.

METHODS

A systematic search of PubMed, EmBase, and Cochrane databases was performed. Five genetic models (allelic, dominant, recessive, heterozygous and homozygous models) were used to analyze the associations, and trial sequential analysis was used to analyze the robustness of the results.

RESULTS

We collected and analyzed the results of seven trials including a total of 2287 patients in our meta-analysis. A total of 8 SNPs were tested in IBD patients. For rs1800629 of TNF-α, the allelic model showed that polymorphism at this locus significantly increased the risk of IBD-associated CRC in IBD patients (OR 4.45, 95% CI 3.18-6.21, P < 0.001). The results also showed a significant association between rs1800629 and an IBD-associated CRC population (heterozygous model: OR 4.335, 95% CI 2.329-8.069, P < 0.001; homozygous model: OR 11.5, 95% CI 2.498-52.592, P = 0.002; dominant model: OR 4.986, 95% CI 2.754-9.026, P < 0.001; recessive model: OR 7.208, 95% CI 1.588-32.72, P = 0.01). Other studies have found that mutation of rs1143627 of IL1B (allelic model: OR 2.97; 95% CI 1.74-5.05, P < 0.001) and rs1050152 of OCTN1 (allelic model: OR 1.637, 95% CI 1.078-2.485, P = 0.021) increased the proportion of IBD-associated CRC in the population. Moreover, there were significant associations between IBD-associated CRC and ITLN rs2274910, gene desert rs1551398 and rs4871611, FCGR2A rs1801274, and S100-Z rs7712957 in the allelic model.

CONCLUSION

Associations between SNPs and the proportion of IBD-associated CRC in IBD patients were examined, and further investigation of additional SNPs and their association with the risk of morbidity is needed.