scholarly journals Stage-differentiated modelling of DNA methylation landscapes uncovers salient biomarkers and prognostic signatures in colorectal cancer progression

Author(s):  
Sangeetha Muthamilselvan ◽  
Abirami Raghavendran ◽  
Ashok Palaniappan

ABSTRACTBackgroundAberrant methylation of DNA acts epigenetically to skew the gene transcription rate up or down. In this study, we have developed a comprehensive computational framework for the stage-differentiated modelling of DNA methylation landscapes in colorectal cancer. Methods: The methylation β - matrix was derived from the public-domain TCGA data, converted into M-value matrix, annotated with sample stages, and analysed for stage-salient genes using multiple approaches involving stage-differentiated linear modelling of methylation patterns and/or expression patterns. Differentially methylated genes (DMGs) were identified using a contrast against control samples (adjusted p-value <0.001 and |log fold-change of M-value| >2). These results were filtered using a series of all possible pairwise stage contrasts (p-value <0.05) to obtain stage-salient DMGs. These were then subjected to a consensus analysis, followed by Kaplan–Meier survival analysis to explore the relationship between methylation and prognosis for the consensus stage-salient biomarkers.ResultsWe found significant genome-wide changes in methylation patterns in cancer samples relative to controls agnostic of stage. Our stage-differentiated analysis yielded the following stage-salient genes: one stage-I gene (FBN1), one stage-II gene (FOXG1), one stage-III gene (HCN1) and four stage-IV genes (NELL1, ZNF135, FAM123A, LAMA1). All the biomarkers were hypermethylated, indicating down-regulation and signifying a CpG island Methylator Phenotype (CIMP) manifestation. A prognostic signature consisting of FBN1 and FOXG1was significantly associated with patient survival (p-value < 0.01) and could be used as a biomarker panel for early-stage CRC prognosis.ConclusionOur workflow for stage-differentiated consensus analysis has yielded stage-salient diagnostic biomarkers as well as an early-stage prognostic biomarker panel. In addition, our studies have affirmed a novel CIMP-like signature in colorectal cancer, urging clinical validation.

2021 ◽  
Author(s):  
Sangeetha Muthamilselvan ◽  
Abirami Raghavendran ◽  
Ashok Palaniappan

Abstract Background: Aberrant DNA methylation acts epigenetically to skew the gene transcription rate up or down, with causative roles in the etiology of cancers. However research on the role of DNA methylation in driving the progression of cancers is limited. In this study, we have developed a comprehensive computational framework for the stage-differentiated modelling of DNA methylation landscapes in colorectal cancer (CRC), and unravelled significant stagewise signposts of CRC progression. Methods: The methylation β - matrix was derived from the public-domain TCGA data, converted into M-value matrix, annotated with AJCC stages, and analysed for stage-salient genes using multiple approaches involving stage-differentiated linear modelling of methylation patterns and/or expression patterns. Differentially methylated genes (DMGs) were identified using a contrast against controls (adjusted p-value <0.001 and |log fold-change of M-value| >2). These results were filtered using a series of all possible pairwise stage contrasts (p-value <0.05) to obtain stage-salient DMGs. These were then subjected to a consensus analysis, followed by Kaplan–Meier survival analysis to evaluate the impact of methylation patterns of consensus stage-salient biomarkers on disease prognosis.Results: We found significant genome-wide changes in methylation patterns in cancer cases relative to controls agnostic of stage. Our stage-differentiated analysis yielded the following stage-salient genes: one stage-I gene (FBN1), one stage-II gene (FOXG1), one stage-III gene (HCN1) and four stage-IV genes (NELL1, ZNF135, FAM123A, LAMA1). All the biomarkers were hypermethylated, indicating down-regulation and signifying a CpG island Methylator Phenotype (CIMP) manifestation. A significant prognostic signature consisting of FBN1 and FOXG1 survived all the steps of our analysis pipeline, and represents a novel early-stage biomarker. Conclusions: We have designed a workflow for stage-differentiated consensus analysis, and identified stage-salient diagnostic biomarkers and an early-stage prognostic biomarker panel. Our studies further yield a novel CIMP-like signature of potential clinical import underlying CRC progression.


2020 ◽  
Vol 10 ◽  
Author(s):  
Yuan Quan ◽  
Fengji Liang ◽  
Deqing Wu ◽  
Xueqing Yao ◽  
Zhihuang Hu ◽  
...  

There is a body of evidence that the aging immune system is linked to cancer. In this study, with aging- and immune-related DNA methylation data, we investigated the DNA methylation regulation changes in promoters with other regions of genes during aging and their association with the immune-cell proportion in the circulating whole blood of individuals. The analyses for aging- and CD4+ T cell proportion-derived differential genes showed that ubiquitination plays an important role in the aging immune system and tumorigenesis. Therefore, starting from a set of pre-annotated ubiquitination genes, we found that among the differentially ubiquitinated genes, DZIP3, an E3 ubiquitin ligase with no reports on its function in immune cells and tumorigenesis, was significantly associated with both aging (P-value = 3.86e-06) and CD4+ T cell proportion (P-value = 1.97e-05) in circulating blood. By collecting a cohort of 100 colon cancer patients and 50 healthy individuals, we validated that the 1st exon DNA methylation of DZIP3 could predict the onset of early stage (AUC = 0.833, OR = 8.82) and all pTNM stages of colorectal cancer (AUC = 0.782, OR = 5.70). Thus, the epigenetically regulated ubiquitination machine plays an important role in immune aging and tumorigenesis.


Cancers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 2762
Author(s):  
Samantha Di Donato ◽  
Alessia Vignoli ◽  
Chiara Biagioni ◽  
Luca Malorni ◽  
Elena Mori ◽  
...  

Adjuvant treatment for patients with early stage colorectal cancer (eCRC) is currently based on suboptimal risk stratification, especially for elderly patients. Metabolomics may improve the identification of patients with residual micrometastases after surgery. In this retrospective study, we hypothesized that metabolomic fingerprinting could improve risk stratification in patients with eCRC. Serum samples obtained after surgery from 94 elderly patients with eCRC (65 relapse free and 29 relapsed, after 5-years median follow up), and from 75 elderly patients with metastatic colorectal cancer (mCRC) obtained before a new line of chemotherapy, were retrospectively analyzed via proton nuclear magnetic resonance spectroscopy. The prognostic role of metabolomics in patients with eCRC was assessed using Kaplan–Meier curves. PCA-CA-kNN could discriminate the metabolomic fingerprint of patients with relapse-free eCRC and mCRC (70.0% accuracy using NOESY spectra). This model was used to classify the samples of patients with relapsed eCRC: 69% of eCRC patients with relapse were predicted as metastatic. The metabolomic classification was strongly associated with prognosis (p-value 0.0005, HR 3.64), independently of tumor stage. In conclusion, metabolomics could be an innovative tool to refine risk stratification in elderly patients with eCRC. Based on these results, a prospective trial aimed at improving risk stratification by metabolomic fingerprinting (LIBIMET) is ongoing.


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.


2015 ◽  
Vol 51 ◽  
pp. S81
Author(s):  
T.H. Wang ◽  
P.C. Lin ◽  
Y.P. Lee ◽  
B.W. Lin ◽  
P.F. Kuo ◽  
...  

Author(s):  
Bhongir Aparna Varma ◽  
Srilatha Bashetti ◽  
Rajagopalan Vijayaraghavan ◽  
Kumar Sai Sailesh

 Epigenetics is one of the exciting and fastest expanding fields of biology; this is above genetics. Methylation is the process involved in the transfer of methyl group to amino acids, proteins, enzymes and DNA of all the cells, and tissues of the body. During cell-division low folate availability may result in decreased production of thymidine wherein uracil may be substituted in the place of thymidine in the DNA sequence. It was reported that folate and Vitamin B12 restricted diet resulted in aberrant methylation patterns. The current review was undertaken to explore the role of folic acid and Vitamin B12 in DNA methylation.


Author(s):  
Moumouni Konate ◽  
Michael J. Wilkinson ◽  
Banjamin Mayne ◽  
Eileen Scott ◽  
Bettina Berger ◽  
...  

The barley (Hordeum vulgare) genome comprises over 32,000 genes, with differentiated cells expressing only a subset of genes; the remainder being silent. Mechanisms by which tissue-specific genes are regulated are not entirely understood, although DNA methylation is likely to be involved. DNA methylation patterns are not static during plant development, but it is still unclear whether different organs possess distinct methylation profiles. Methylation-sensitive GBS was used to generate DNA methylation profiles for roots, leaf-blades and leaf-sheaths from five barley varieties, using seedlings at the three-leaf stage. Differentially Methylated Markers (DMMs) were characterised by pairwise comparisons of roots, leaf-blades and leaf-sheaths of three different ages. While very many DMMs were found between roots and leaf parts, only a few existed between leaf-blades and leaf-sheaths, with differences decreasing with leaf rank. Organ-specific DMMs appeared to target mainly repeat regions, implying that organ differentiation partially relies on the spreading of DNA methylation from repeats to promoters of adjacent genes. Furthermore, the biological functions of differentially methylated genes in the different organs correlated with functional specialisation. Our results indicate that different organs do possess diagnostic methylation profiles and suggest that DNA methylation is important for both tissue development and differentiation and organ function.


2020 ◽  
Vol 79 (OCE2) ◽  
Author(s):  
Jiantao Ma ◽  
Casey Rebholz ◽  
Kim Braun ◽  
Lindsay Reynolds ◽  
Stella Aslibekyan ◽  
...  

AbstractLeukocyte DNA methylation patterns associated with habitual diet may reveal molecular mechanisms involved in the pathogenesis of diet-related chronic diseases and highlight targets for prevention and treatment. We aimed to examine peripheral blood derived leukocyte DNA methylation signatures associated with diet quality. We meta-analyzed epigenome-wide associations between diet quality and DNA methylation levels at over 400,000 cytosine-guanine dinucleotides (CpGs). We conducted analysis primarily in 6,662 European ancestry (EA) participants and secondarily in a group additionally including 3,062 participants of non-European ancestry from five population-based cohort studies. DNA methylation profiles were measured in whole blood, CD4 + T-cells, or CD14 + monocytes. We used food frequency questionnaires to assess habitual intake and constructed two diet quality scores: the Mediterranean-style diet score (MDS) and Alternative Healthy Eating Index (AHEI). Our primary analysis identified 32 diet-associated CpGs, 12 CpGs for MDS and 24 CpGs for AHEI (at FDR < 0.05, corresponding p-values = 1.2×10-6 and 3.1×10-6, respectively) in EA participants. Four of these CpGs were associated with both MDS and AHEI. In addition, Mendelian randomization analysis indicated that seven diet-associated CpGs were causally linked to at least one of the CVD risk factors. For example, hypermethylation of cg11250194 (FADS2), which was associated with higher diet quality scores, was also associated with lower fasting triglycerides concentrations (p-value = 1.5×10-14) and higher high-density lipoprotein cholesterol concentrations (p-value = 1.7×10-8). Transethnic meta-analysis identified nine additional CpGs associated with diet quality (either MDS or AHEI) at FDR < 0.05. Overall quality of habitual diet was associated with differential peripheral leukocyte DNA methylation levels of 32 CpGs in EA participants. The diet-associated CpGs may serve as biomarkers and targets for preventive measures in CVD health. Future studies are warranted to examine diet-associated DNA methylation patterns in larger, ethnically diverse study samples.


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.


PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2112 ◽  
Author(s):  
Charinya Pimson ◽  
Tipaya Ekalaksananan ◽  
Chamsai Pientong ◽  
Supannee Promthet ◽  
Nuntiput Putthanachote ◽  
...  

Background.Assessment of DNA methylation of specific genes is one approach to the diagnosis of cancer worldwide. Early stage detection is necessary to reduce the mortality rate of cancers, including those occurring in the stomach. For this purpose, tumor cells in circulating blood offer promising candidates for non-invasive diagnosis. Transcriptional inactivation of tumor suppressor genes, likePCDH10andRASSF1A, by methylation is associated with progression of gastric cancer, and such methylation can therefore be utilized as a biomarker.Methods.The present research was conducted to evaluate DNA methylation in these two genes using blood samples of gastric cancer cases. Clinicopathological data were also analyzed and cumulative survival rates generated for comparison.Results.High frequencies ofPCDH10andRASSF1Amethylations in the gastric cancer group were noted (94.1% and 83.2%, respectively, as compared to 2.97% and 5.45% in 202 matched controls). Most patients (53.4%) were in severe stage of the disease, with a median survival time of 8.4 months after diagnosis. Likewise, the patients with metastases, orRASSF1AandPCDH10methylations, had median survival times of 7.3, 7.8, and 8.4 months, respectively. A Kaplan–Meier analysis showed that cumulative survival was significantly lower in those cases positive for methylation ofRASSF1Athan in their negative counterparts. Similarly, whereas almost 100% of patients positive forPCDH10methylation had died after five years, none of the negative cases died over this period. Notably, the methylations ofRASSF1AandPCDH10were found to be higher in the late-stage patients and were also significantly correlated with metastasis and histology.Conclusions.PCDH10andRASSF1Amethylations in blood samples can serve as potential non-invasive diagnostic indicators in blood for gastric cancer. In addition toRASSF1Amethylation, tumor stage proved to be a major prognostic factor in terms of survival rates.


Sign in / Sign up

Export Citation Format

Share Document