Alu Hypomethylation in Smoke-Exposed Epithelia and Oral Squamous Carcinoma

Puttipanyalears, Charoenchai; Subbalekha, Keskanya; Mutirangura, Apiwat; Kitkumthorn, Nakarin

doi:10.7314/apjcp.2013.14.9.5495

Cited by 26 publications

(25 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Ten papers used saliva [9, 10, 12, 14, 17, 27, 29, 32, 50], sixteen papers used solid tissue [11, 15, 16, 18, 19, 23–26, 30, 31, 33–38, 40–46, 49], four papers used blood [21, 28, 31, 39], five papers used both solid tissue and saliva [8, 13, 22, 47, 51], and two papers used both solid tissue and blood (Table 1) [20, 33]. The studies evaluated the diagnostic power of methylation biomarkers as follows: thirty-five studies were based on a single gene [8, 12–14, 16–19, 21, 23, 25–28, 30, 32–51], two papers were based on multiple genes [9, 22] and seven papers were based on both single and multiple genes [10, 11, 15, 20, 24, 29, 31].…”

Section: Resultsmentioning

confidence: 99%

Diagnostic accuracy of DNA methylation for head and neck cancer varies by sample type and number of markers tested

Chen

Jiang

et al. 2016

Oncotarget

View full text Add to dashboard Cite

Abnormal methylation of certain cancer related genes strongly predicts a diagnosis of head and neck cancer (HNC), while the predictive power of methylation of other DNA markers for HNC remains unclear. To systemically assess the diagnostic value of DNA methylation patterns for HNC and the effect of methylation platform techniques and sample types, we performed a PubMed search for studies of the correlation between DNA methylation and HNC completed before July 2016, and extracted the sensitivity and specificity for methylated biomarkers. Across these studies, DNA methylation showed high sensitivity for diagnosing HNC in solid tissue (0.57), and high specificity in saliva (0.89). Area under the curve (AUC) from summary receiver operating characteristic (SROC) curves revealed that DNA methylation had more diagnostic power in solid tissue (AUC = 0.82) than saliva (AUC = 0.80) or blood (AUC = 0.77). Combinations of multiple methylated genes were more sensitive diagnostic markers than single methylated genes. Our results suggest that the diagnostic accuracy of methylated biomarkers for HNC varied by sample type and were most accurate when results from multiple sample types were considered.

show abstract

Section: Resultsmentioning

confidence: 99%

Diagnostic accuracy of DNA methylation for head and neck cancer varies by sample type and number of markers tested

Chen

Jiang

et al. 2016

Oncotarget

View full text Add to dashboard Cite

show abstract

“…The level of Alu methylation was noted to be stepwise decreased, concordant with the potentially malignant changes of the oral epithelium. 75 Another group showed a hypomethylated pattern of LINE-1s in oral epithelial cells of smokers in comparison to non-smokers. 15 The mechanism by which cigarette smoking can lead to changes in the epigenome is unknown.…”

Section: Tp53mentioning

confidence: 98%

DNA methylation analysis of cancer-related genes in oral epithelial cells of healthy smokers

Oliveira¹,

Silva²,

Mariz³

et al. 2015

Archives of Oral Biology

View full text Add to dashboard Cite

“…IRS hypomethylation is commonly observed both in aging [14,20] and cancer cells [21]. IRS hypomethylation is noted in individuals who are exposed to carcinogens, such as benzene [22] and smoke [23]. In cancer cells, both IRS hypomethylation and mutations increase the multistep process of cancer progression [24].…”

mentioning

confidence: 99%

Alu siRNA to Increase Alu Element Methylation and Prevent DNA Damage

et al. 2018

Self Cite

View full text Add to dashboard Cite

Global DNA hypomethylation promoting genomic instability leads to cancer and deterioration of human health with age. Aim: To invent a biotechnology that can reprogram this process. Methods: We used Alu siRNA to direct Alu interspersed repetitive sequences methylation in human cells. We evaluated the correlation between DNA damage and Alu methylation levels. Results: We observed an inverse correlation between Alu element methylation and endogenous DNA damage in white blood cells. Cells transfected with Alu siRNA exhibited high Alu methylation levels, increased proliferation, reduced endogenous DNA damage and improved resistance to DNA damaging agents. Conclusion: Alu methylation stabilizes the genome by preventing accumulation of DNA damage. Alu siRNA could be useful for evaluating reprograming of the global hypomethylation phenotype in cancer and aging cells. DNA methylation at interspersed repetitive sequences (IRSs) plays an important role in maintaining genome stability. Cells with IRS hypomethylation exhibit increased mutation rates [1,2]. Here, we tested whether DNA damage, an alteration in the chemical structure of DNA and a precursor to mutation [3], plays a role in mediating how global hypomethylation promotes genomic instability. Our recent study found that global hypomethylation is associated with plasma 8-hydroxy-2 -deoxyguanosine (8-OHdG) in biliary atresia patients [4]. Moreover, urinary 8-OHdG, DNA strand breaks and global DNA hypomethylation are associated with low serum folate [5] and oxidative stress [6]. Therefore, we hypothesized that the human genome may use DNA methylation in IRSs to prevent DNA damage.This study developed a technology to add DNA methylation at Alu elements. The human genome contains greater than one million Alu elements [7]. Several reports demonstrated de novo methylation by siRNA in plants [8][9][10]. In human cells, small RNA was used to promote DNA methylation, shRNA for long interspersed element-1 (LINE-1) and hepatitis B virus, and siRNA for HIV-1 promoter region [11][12][13]. There are many types of IRS such as Alu elements, LINE-1, and human endogenous retrovirus [14][15][16][17]. To increase DNA methylation, we tested siRNA to unique sequences and several IRS sequences. Our preliminary trial demonstrated that only Alu siRNA could increase methylation of the target sequences. Here, we evaluated whether Alu siRNA is a useful tool to explore the role of global hypomethylation in genomic instability [18].Alu hypomethylation may play a role in causing genomic instability in cancer and aging cells. Genomic instability, the main enabling characteristic of cancer and aging processes [18,19], may mainly be promoted by IRS hypomethylation. IRS hypomethylation is commonly observed both in aging [14,20] and cancer cells [21]. IRS

show abstract

Alu Hypomethylation in Smoke-Exposed Epithelia and Oral Squamous Carcinoma

Cited by 26 publications

References 43 publications

Diagnostic accuracy of DNA methylation for head and neck cancer varies by sample type and number of markers tested

Diagnostic accuracy of DNA methylation for head and neck cancer varies by sample type and number of markers tested

DNA methylation analysis of cancer-related genes in oral epithelial cells of healthy smokers

Alu siRNA to Increase Alu Element Methylation and Prevent DNA Damage

Contact Info

Product

Resources

About