scholarly journals DNA Methylation in Colorectal cancer—Impact on Screening and Therapy Monitoring Modalities?

2007 ◽  
Vol 23 (1-2) ◽  
pp. 51-71 ◽  
Author(s):  
Marion Zitt ◽  
Matthias Zitt ◽  
Hannes M. Müller

Colorectal cancer (CRC) is a common malignancy. It arises from benign neoplasms and evolves into adenocarcinomas through a stepwise histological progression sequence, proceeding from either adenomas or hyperplastic polyps/serrated adenomas. Genetic alterations have been associated with specific steps in this adenoma-carcinoma sequence and are believed to drive the histological progression of CRC. Recently, epigenetic alterations (especially DNA methylation) have been shown to occur in colon polyps and CRC. The aberrant methylation of genes appears to act together with genetic alterations to drive the initiation and progression of colon polyps to CRC.DNA methylation changes have been recognized as one of the most common molecular alterations in human tumors, including CRC. Because of the ubiquity of DNA methylation changes and the ability to detect methylated DNA in several body fluids (blood, stool), this specifically altered DNA may serve, on the one hand, as a possible new screening marker for CRC and, on the other hand, as a tool for therapy monitoring in patients having had neoplastic disease of the colorectum.As many CRC patients present with advanced disease, early detection seems to be one of the most important approaches to reduce mortality. Therefore, an effective screening test would have substantial clinical benefits. Furthermore, early detection of progression of disease in patients having had CRC permits immediate commencement of specific treatment regimens (e.g. curative resection of liver and lung metastases) and probably longer survival and better quality of life.

2005 ◽  
Vol 33 (4) ◽  
pp. 684-688 ◽  
Author(s):  
W.M. Grady

Colon cancers arise from benign neoplasms and evolve into adenocarcinomas through a stepwise histological progression sequence, proceeding from either adenomas or hyperplastic polyps/serrated adenomas. Genetic alterations have been associated with specific steps in this polyp–adenocarcinoma sequence and are believed to drive the histological progression of colon cancer. Recently, epigenetic alterations, which include CGI (CpG island) DNA methylation, have been shown to occur in colon polyps and colon cancer. The aberrant methylation of genes appears to co-operate with the genetic alterations to drive the initiation and progression of colon polyps to colon cancer. CGI DNA methylation is an epigenetic mechanism that represses gene transcription in normal cellular processes, but it becomes excessive and aberrant in many neoplasms. The aberrant DNA methylation affects CpG-rich regions, called CGIs, in the 5′ region of genes and results in transcriptional silencing through effects on transcription factor binding and associated changes in chromatin structure. These hypermethylated genes are not only probable pathogenic events affecting colon-cancer formation, but also neoplasm-specific molecular events that may be useful as molecular markers for colon tumours. Furthermore, aberrant DNA methylation of tumour-suppressor genes may occur secondary to a genetic predisposition or to a field-cancerization effect in the colon and may be useful as molecular markers for the risk of developing colon cancer.


2005 ◽  
Vol 21 (3) ◽  
pp. 105-120 ◽  
Author(s):  
Georg Goebel ◽  
Marion Zitt ◽  
Matthias Zitt ◽  
Hannes M. Müller

It is now widely accepted that there is a need for the development of molecular markers of cancer that can be used for clinical prognostication and monitoring. Approximately a decade ago tumor-derived circulating nucleic acids in the plasma or serum (CNAPS) of cancer patients were introduced as a noninvasive tool for cancer detection. This review focuses on the various types of CNAPS of patients with solid neoplasias (genetic alterations in circulating DNA, microsatellites, methylated DNA, viral DNA, nucleosomes, mitochondrial DNA and cell-free mRNA) and their putative potential as prognostic or predictive parameter or even as a tool for therapy monitoring during follow-up. Additionally, this review aims to point out the difference between a prognostic and a predictive factor in patient bloodstream. However, with rapid technical improvement and well-designed studies we conclude that the next years will see CNAPS analysis integrated in the prognostication and monitoring of cancer patients, thus producing more specific treatment regimens for patients with various stages of neoplastic disease and ultimately longer survival and better quality of life.


2021 ◽  
pp. 1-6
Author(s):  
Ben Kang ◽  
Hyun Seok Lee ◽  
Seong Woo Jeon ◽  
Soo Yeun Park ◽  
Gyu Seog Choi ◽  
...  

BACKGROUND: Colorectal cancer (CRC) is one of the leading causes of mortality and morbidity in the world. It is characterized by different pathways of carcinogenesis and is a heterogeneous disease with diverse molecular landscapes that reflect histopathological and clinical information. Changes in the DNA methylation status of colon epithelial cells have been identified as critical components in CRC development and appear to be emerging biomarkers for the early detection and prognosis of CRC. OBJECTIVE: To explore the underlying disease mechanisms and identify more effective biomarkers of CRC. METHODS: We compared the levels and frequencies of DNA methylation in 11 genes (Alu, APC, DAPK, MGMT, MLH1, MINT1, MINT2, MINT3, p16, RGS6, and TFPI2) in colorectal cancer and its precursor adenomatous polyp with normal tissue of healthy subjects using pyrosequencing and then evaluated the clinical value of these genes. RESULTS: Aberrant methylation of Alu, MGMT, MINT2, and TFPI2 genes was progressively accumulated during the normal-adenoma-carcinoma progression. Additionally, CGI methylation occurred either as an adenoma-associated event for APC, MLH1, MINT1, MINT31, p16, and RGS6 or a tumor-associated event for DAPK. Moreover, relatively high levels and frequencies of DAPK, MGMT, and TFPI2 methylation were detected in the peritumoral nonmalignant mucosa of cancer patients in a field-cancerization manner, as compared to normal mucosa from healthy subjects. CONCLUSION: This study identified several biomarkers associated with the initiation and progression of CRC. As novel findings, they may have important clinical implications for CRC diagnostic and prognostic applications. Further large-scale studies are needed to confirm these findings.


2021 ◽  
Vol 43 (3) ◽  
pp. 1419-1435
Author(s):  
Walter Pulverer ◽  
Kristi Kruusmaa ◽  
Silvia Schönthaler ◽  
Jasmin Huber ◽  
Marko Bitenc ◽  
...  

Early diagnosis of colorectal cancer (CRC) is of high importance as prognosis depends on tumour stage at the time of diagnosis. Detection of tumour-specific DNA methylation marks in cfDNA has several advantages over other approaches and has great potential for solving diagnostic needs. We report here the identification of DNA methylation biomarkers for CRC and give insights in our methylation-sensitive restriction enzyme coupled qPCR (MSRE-qPCR) system. Targeted microarrays were used to investigate the DNA methylation status of 360 cancer-associated genes. Validation was done by qPCR-based approaches. A focus was on investigating marker performance in cfDNA from 88 patients (44 CRC, 44 controls). Finally, the workflow was scaled-up to perform 180plex analysis on 110 cfDNA samples, to identify a DNA methylation signature for advanced colonic adenomas (AA). A DNA methylation signature (n = 44) was deduced from microarray experiments and confirmed by quantitative methylation-specific PCR (qMSP) and by MSRE-qPCR, providing for six genes’ single areas under the curve (AUC) values of >0.85 (WT1, PENK, SPARC, GDNF, TMEFF2, DCC). A subset of the signatures can be used for patient stratification and therapy monitoring for progressed CRC with liver metastasis using cfDNA. Furthermore, we identified a 35-plex classifier for the identification of AAs with an AUC of 0.80.


2019 ◽  
Vol 26 (7) ◽  
pp. R415-R439 ◽  
Author(s):  
Carles Zafon ◽  
Joan Gil ◽  
Beatriz Pérez-González ◽  
Mireia Jordà

In recent years, cancer genomics has provided new insights into genetic alterations and signaling pathways involved in thyroid cancer. However, the picture of the molecular landscape is not yet complete. DNA methylation, the most widely studied epigenetic mechanism, is altered in thyroid cancer. Recent technological advances have allowed the identification of novel differentially methylated regions, methylation signatures and potential biomarkers. However, despite recent progress in cataloging methylation alterations in thyroid cancer, many questions remain unanswered. The aim of this review is to comprehensively examine the current knowledge on DNA methylation in thyroid cancer and discuss its potential clinical applications. After providing a general overview of DNA methylation and its dysregulation in cancer, we carefully describe the aberrant methylation changes in thyroid cancer and relate them to methylation patterns, global hypomethylation and gene-specific alterations. We hope this review helps to accelerate the use of the diagnostic, prognostic and therapeutic potential of DNA methylation for the benefit of thyroid cancer patients.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Chih-Hsiung Hsu ◽  
Cheng-Wen Hsiao ◽  
Chien-An Sun ◽  
Wen-Chih Wu ◽  
Tsan Yang ◽  
...  

AbstractThis study provide an insight that the panel genes methylation status in different clinical stage tended to reflect a different prognosis even in matched normal tissues, to clinical recommendation. We enrolled 153 colorectal cancer patients from a medical center in Taiwan and used the candidate gene approach to select five genes involved in carcinogenesis pathways. We analyzed the relationship between DNA methylation with different cancer stages and the prognostic outcome. There were significant trends of increasing risk of 5-year time to progression and event-free survival of subjects with raising number of hypermethylation genes both in normal tissue and tumor tissue. The group with two or more genes with aberrant methylation in the advanced cancer stages (Me/advanced) had lower 5-year event-free survival among patients with colorectal cancer in either normal or tumor tissue. The adjusted hazard ratios in the group with two or more genes with aberrant methylation with advanced cancer stages (Me/advanced) were 8.04 (95% CI, 2.80–23.1; P for trend <0.01) and 8.01 (95% CI, 1.92–33.4; P for trend <0.01) in normal and tumor tissue, respectively. DNA methylation status was significantly associated with poor prognosis outcome. This finding in the matched normal tissues of colorectal cancer patients could be an alternative source of prognostic markers to assist clinical decision making.


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