FHIT Methylation Research Articles

Corrigendum: EGFR Mutation and FHIT Methylation: Inverse Relationship in Patients with Lung Adenocarcinoma and Tuberculosis

Correction The funding in the original publication (https://www.doi.org/10.26689/par.v8i2.6444) is incorrect. The original funding was: The Ethnic Minority Science and Technology Program of Xinjiang Autonomous Region (201523122) The correct funding should be as follows: This project was supported by Natural Science Foundation of Xinjiang Uygur Autonomous Region (2020D01A107)

Integrated DNA methylation analysis of peripheral blood from asbestos exposed populations and patients with malignant mesothelioma reveals novel methylation driver genes of diagnostic and prognostic relevance

Effective biomarkers are paramount importance for the early detection and prognosis prediction of malignant mesothelioma (MM) which mainly caused by asbestos exposure, and DNA methylation has been demonstrated to be a potentially powerful diagnostic tool. To elucidate the relationship between asbestos exposure and alterations in DNA methylation patterns, as well as the potential diagnostic and prognostic value of differentially methylated regions and CpG sites (DMRs/DMCs) in the progression of MM. The current study employed reduced representation bisulfite sequencing (RRBS) to examine the genome-wide DNA methylation profiles in the peripheral blood of individuals exposed to asbestos and those diagnosed with MM, in comparison to the controls, and DMRs/DMCs were subsequently validated by targeted bisulfite sequencing (TBS). Our results suggested that there were 12 DMRs/DMCs exhibiting a consistent change trend of DNA methylation in both RRBS and TBS results. Significant correlations were observed between DNA methylation levels of DMRs/DMCs and the duration of occupational asbestos exposure. The evaluation of the receiver operating characteristic (ROC) curve suggested that the DNA methylation status of FHIT, CCR12P and CDH15 may serve as diagnosis indicator in distinguishing MM patients from healthy controls and those exposed to asbestos. Our findings offer a foundation for the role of DNA methylation in the development of MM induced by asbestos exposure. The potential significance of FHIT, CCR12P and CDH15 DNA methylation alterations in the pathogenesis and advancement of MM disease suggests their potential as diagnostic and prognostic biomarkers.

EGFR Mutation and FHIT Methylation: Inverse Relationship in Patients with Lung Adenocarcinoma and Tuberculosis

Objective: To investigate the genetic correlations between epithelial growth factor receptor (EGFR) mutation and FHIT methylation in patients diagnosed with lung adenocarcinoma (AC) and pulmonary tuberculosis (TB). Methods: The presence of EGFR mutations and the methylation status of the FHIT gene in patients presenting with AC and TB were analyzed. The correlation between TB status and the observed genetic and epigenetic variations was also examined. Results: Among the 90 patients included in the study, 38 exhibited EGFR mutations (14 among those with TB and 24 among those without TB), while 29 exhibited FHIT myelination (19 among those with TB and 10 among those without TB). Furthermore, the protein expression levels of EGFR and FHIT were significantly higher in patients diagnosed solely with AC compared to those presenting with both AC and TB. A robust inverse correlation was identified between TB status and the frequency of EGFR mutation (P < 0.001). Moreover, significant associations were observed between TB status and FHIT methylation (P < 0.01). Conclusion: The findings suggest a correlation between TB and the prevalence of EGFR mutation and FHIT methylation in the pathogenesis of AC.

High-risk HPV infection-associated hypermethylated genes in oropharyngeal squamous cell carcinomas

BackgroundHPV-positive oropharyngeal squamous cell carcinomas (OPSCCs) are sensitive to chemo-radiation therapy and have favorable survival outcomes compared with HPV-negative cancers. These tumors are usually not related to tobacco and alcohol exposure. Therefore, diagnosing HPV-positive OPSCCs for the appropriate disease management is crucial, and no suitable markers are available for detecting early malignancies in HPV-infected tissues. In this study, we attempt to find HPV-specific epigenetic biomarkers for OPSCCs.MethodsA total of 127 surgical samples were analyzed for HPV positivity and promoter methylation of a panel of genes. HPV detection was performed by PCR detection of HPV E6 and E7 viral oncoproteins. In addition, promoter methylation of a total of 8 genes (DAPK, FHIT, RASSF1A, TIMP3, AGTR1, CSGALNACT2, GULP1 and VGF) was analyzed by quantitative-methylation specific PCR (QMSP), and their associations with HPV positivity or RB/p16 expressions were evaluated.ResultsAGTR1 and FHIT were frequently methylated in HPV-positive OPSCC samples with a good area under the curve (AUC over 0.70). In addition, these genes' promoter methylation was significantly associated with p16 positive and RB negative cases, which were the characteristics of OPSCC cases with favorable survival outcomes. Either AGTR1 or FHIT methylated cases were significantly associated with HPV-positive cancers with 92.0% sensitivity (P < 0.001). Also, they had significantly better overall survival (P = 0.047) than both unmethylated cases.ConclusionsA combination of AGTR1 and FHIT methylation demonstrated a suitable detection marker of OPSCCs derived from the HPV-infected field, familiar with p16-positive and RB-negative phenotypes.

Methylation of PCDH17 and NEFH as prognostic biomarker for nonmetastatic RCC: A cohort study.

DNA methylation makes up a main part of the molecular mechanism of cancer evolution and has shown promising results in the prognosis of renal cell cancer (RCC). In this study, we investigated the possible association of promoter methylation of PCDH17, NEFH, RASSF1A, and FHIT, genes with the prognosis of nonmetastatic RCC patients. Cancerous and normal adjacent tissues from surgical specimens of 41 patients with long follow-up were treated for DNA isolation and bisulfite conversion. The gene promoter methylation was determined with quantitative methylation-specific PCR (qMSP). Wilcoxon signed-rank test was used for paired methylation comparisons, while univariate linear regression and Mann-Whitney test were applied for associating methylation status with clinical and disease characteristics. Cox regression proportional hazards models and Kaplan-Meier plots were used for survival analyses in reference to methylation status. Paired comparisons showed tissue-specific hypermethylation for PCDH17 (P < .001), NEFH (P < .001), RASSF1A (P = .032), while a positive association of methylation in normal tissues with age was demonstrated for PCDH17 (P < .001), RASSF1A (P < .001), FHIT (P < .001). PCDH17 was more methylated in cases with clear cell RCC (P = .015) and high-grade tumor (P = .013), while NEFH methylation was higher in locally advanced cases (P = .032). PCDH17 hypermethylation in cancerous and normal tissues was linked to shorter disease-specific survival (DSS, P = .026, P = .004), disease-free survival (DFS, P = .004, P = .019) while NEFH hypermethylation in cancerous tissues was related to shorter DSS (P = .032). Increased methylation difference of NEFH was also associated with shorter DSS (P = .041) and DFS (P = .020), while the corresponding parameter for PCDH17 was associated with poor DFS (P = .014). Kaplan-Meier curves for hypermethylation in cancer tissues demonstrated different clinical courses for PCDH17 (P = .017), NEFH (P = .023) regarding DSS, and PCDH17 (P = .001) regarding DFS. Our study not only highlights the prognostic value of promoter methylation of PCDH17 and NEFH in cancer tissues but also is the first report of the prognostic value of methylation alterations in normal tissues. Our findings are the first report of the prognostic value of methylation alterations in normal tissues, which can contribute to improved assessment of recurrence risk.

FHIT as a biomarker for early screening of adult T-cell leukemia.

Adult T-cell leukemia (ATL) is an incurable leukemia deriving from human T-cell leukemia virus (HTLV-I) infected cells. In our most recent study, we discovered that methylation of the tumor suppressor, fragile histidine triad gene (FHIT), exists in the majority of acute and chronic ATL patients. Methylation was seen in non-tumorigenic cells, in cells with low levels of HTLV-I integrated DNA, in longitudinal samples from HTLV-I carriers, in a percentage of HTLV-I carriers, and in direct descendants of ATL patients. Overall, this suggests that FHIT methylation is likely present in patients, prior to HTLV-I infection, and predisposes HTLV-I carriers to ATL development. In this commentary we discuss the importance of developing diagnostic tools for the early detection of FHIT methylation and the possibility that prior FHIT methylation may predispose any individual to the development of cancer.

Role of Molecular Mutations, Telomerase and Promoter Methylation Status of the TSGs (p15INK4b, SOCS-1, Calcitonin and FHIT) in Disease Severity, Progression and Survival in a Series of 100 MDS Patients: A Study from India

In contrast to the Western countries, Myelodysplastic syndromes (MDS) in India is being increasingly seen in young adults. The severity of the disease is more in Indian patients at time of presentation; moreover their response to treatment is poor. In the present study molecular markers which may affect the biology of MDS patients were studied.Conventional cytogenetics, molecular mutations of RAS and FLT3 genes, hTERT gene expression, telomerase activity (TA) and promoter methylation status of four tumor suppressor genes (TSGs) (p15INK4b, SOCS-1, calcitonin and FHIT) were analyzed in a series of 100 MDS patients and correlated with disease severity, progression and survival. It was found that the prevalence of MDS was higher in patients with age&lt;60 years as compared to the patients with age ≥ 60 years (75% vs. 25%). Normal cytogenetics was present in 26/51 (51%) patients and 25/51 (49%) patients had chromosomal abnormalities. The frequency of N-RAS mutation was 3% and K-RAS mutation was 9%. FLT3-ITD and FLT3-TKD mutations were absent. TA was increased in 17/100 (17%) cases. hTERT expression was present in 17/100 (17%) cases. 40 patients (40%) had p15INK4b gene methylation. p15INK4b, SOCS-1, FHIT and calcitonin gene methylation was observed in 40 (40%), 53 (53%), 43 (43%) and 58 (58%) patients respectively. After multivariate analysis, only p15INK4b gene methylation was found as an independent predictor for progression of disease in MDS patients. In conclusion, p15INK4b gene methylation may play pivotal role in the diagnosis and disease progression in younger Indian MDS patients.

Relationship between the Methylation of Folic Acid Metabolism-Related Genes and the Incidence and Prognosis of Esophageal Cancer among Ethnic Kazakhs.

Objective: To investigate the relationship between the hypermethylation of folic acid metabolism-related genes and the incidence and prognosis of esophageal cancer among ethnic Kazakhs in Xinjiang (China).Methods: According to the standard of esophageal cancer diagnosis, exclusion and epidemiological investigation of the experimental and control groups. Ion capture immunoassays were used to measure serum folic acid levels, while methylation-specific polymerase chain reaction was used to detect gene promoter methylation levels. Log-rank tests and Cox regression models were used to identify prognostic factors in the patient population.Results: Serum folic acid levels in the experimental (cancer) group were significantly lower than in the control (non-cancer) group (Z = -9.13, P < 0.001). Furthermore, the methylation rates of MTHFR, CBS, MGMT, P16, FHIT, and RASSF1A in the experimental group were significantly higher than in the control group. Multivariate analysis identified depth of tumor invasion, regional lymph node metastasis, tumor-node-metastasis stage, and CBS and RASSF1A gene methylation status as independent prognostic factors; female gender and high serum folic acid levels were favorable prognostic factors.Conclusions: Low serum folic acid level is a risk factor for esophageal cancer among ethic Kazakhs. Moreover, methylation of MTHFR, CBS, MGMT, P16, FHIT, and RASSF1A is closely related to esophageal cancer tumorigenesis.

Quantitative assessment of the diagnostic role of FHIT promoter methylation in non-small cell lung cancer.

Aberrant methylation of CpG islands acquired in promoter regions plays an important role in carcinogenesis. Accumulated evidence demonstrates FHIT gene promoter hyper-methylation is involved in non-small cell lung cancer (NSCLC). To test the diagnostic ability of FHIT methylation status on NSCLC, thirteen studies, including 2,119 samples were included in our meta-analysis. Simultaneously, four independent DNA methylation datasets from TCGA and GEO database were analyzed for validation. The pooled odds ratio of FHIT promoter methylation in cancer samples was 3.43 (95% CI: 1.85 to 6.36) compared with that in controls. In subgroup analysis, significant difference of FHIT gene promoter methylation status in NSCLC and controls was found in Asians but not in Caucasian population. In validation stage, 950 Caucasian samples, including 126 paired samples from TCGA, 568 cancer tissues and 256 normal controls from GEO database were analyzed, and all 8 CpG sites near the promoter region of FHIT gene were not significantly differentially methylated. Thus the diagnostic role of FHIT gene in the lung cancer may be relatively limited in the Caucasian population but useful in the Asians.

DNA methylation and breast tumor clinicopathological features: The Western New York Exposures and Breast Cancer (WEB) study

ABSTRACTWe evaluated the association between methylation of 9 genes, SCGB3A1, GSTP1, RARB, SYK, FHIT, CDKN2A, CCND2, BRCA1, and SFN in tumor samples from 720 breast cancer cases with clinicopathological features of the tumors and survival. Logistic regression was used to estimate odds ratios (OR) of methylation and Cox proportional hazards models to estimate hazard ratios (HR) between methylation and breast cancer related mortality. Estrogen receptor (ER) and progesterone receptor (PR) positivity were associated with increased SCGB3A1 methylation among pre- and post-menopausal cases. Among premenopausal women, compared with Stage 0 cases, cases of invasive cancer were more likely to have increased methylation of RARB (Stage I OR = 4.7, 95% CI: 1.1–19.0; Stage IIA/IIB OR = 9.7, 95% CI: 2.4–39.9; Stage III/IV OR = 5.6, 95% CI: 1.1–29.4) and lower methylation of FHIT (Stage I OR = 0.2, 95% CI: 0.1–0.9; Stage IIA/IIB OR = 0.2, 95% CI: 0.1–0.8; Stage III/IV OR = 0.6, 95% CI: 0.1–3.4). Among postmenopausal women, methylation of SYK was associated with increased tumor size (OR = 1.7, 95% CI: 1.0–2.7) and higher nuclear grade (OR = 2.0, 95% CI 1.2–3.6). Associations between methylation and breast cancer related mortality were observed among pre- but not post-menopausal women. Methylation of SCGB3A1 was associated with reduced risk of death from breast cancer (HR = 0.41, 95% CI: 0.17–0.99) as was BRCA1 (HR = 0.41, 95% CI: 0.16–0.97). CCND2 methylation was associated with increased risk of breast cancer mortality (HR = 3.4, 95% CI: 1.1–10.5). We observed differences in methylation associated with tumor characteristics; methylation of these genes was also associated with breast cancer survival among premenopausal cases. Understanding of the associations of DNA methylation with other clinicopathological features may have implications for prevention and treatment.

Regions of variable DNA methylation in human placenta associated with newborn neurobehavior

ABSTRACTThe placenta regulates the in utero environment and functionally impacts fetal development. Candidate gene studies identified variation in placental DNA methylation is associated with newborn neurologic and behavioral outcomes including movement quality, lethargic behavior, attention, and arousal. We sought to identify novel regions of variable DNA methylation associated with newborn attention, lethargy, quality of movement, and arousal by performing an epigenome-wide association study in 335 infants from a US birth cohort. Methylation status was quantified using the Illumina HumanMethylation450 BeadChip array and associations to newborn outcomes assessed by the NICU Network Neurobehavioral Scales (NNNS) were identified while incorporating established bioinformatics algorithms to control for confounding by cell type composition. Methylation of CpGs within FHIT (cg15970800) and ANKRD11 (cg16710656) demonstrated genome-wide significance (P < 1.8 × 10−7) in specific associations with infant attention. CpGs whose differential methylation was associated with all 4 neurobehavioral outcomes were common to 50 genes involved in biological processes relating to cellular adhesion and nervous system development. Comprehensive methylation profiling identified relationships between methylation of FHIT and ANKRD11, which have been previously linked to neurodevelopment and behavioral outcomes in genetic association studies. Subtle changes in DNA methylation of these genes within the placenta may impact normal variation of a newborn's ability to alter and track visual and auditory stimuli. Gene ontology analysis suggested that those genes with variable methylation related to these outcomes are over-represented in biological pathways involved in brain development and placental physiology, supportive of our hypothesis for a key role of the placenta in neurobehavioral outcomes.

The detective, prognostic, and predictive value of DNA methylation in human esophageal squamous cell carcinoma.

Esophageal cancer is one of the most common malignancies in the world. Squamous cell carcinoma accounts for approximately 90 % of esophageal cancer cases. Genetic and epigenetic changes have been found to accumulate during the development of various cancers, including esophageal squamous carcinoma (ESCC). Tobacco smoking and alcohol consumption are two major risk factors for ESCC, and both tobacco and alcohol were found to induce methylation changes in ESCC. Growing evidence demonstrates that aberrant epigenetic changes play important roles in the multiple-step processes of carcinogenesis and tumor progression. DNA methylation may occur in the key components of cancer-related signaling pathways. Aberrant DNA methylation affects genes involved in cell cycle, DNA damage repair, Wnt, TGF-β, and NF-κB signaling pathways, including P16, MGMT, SFRP2, DACH1, and ZNF382. Certain genes methylated in precursor lesions of the esophagus demonstrate that DNA methylation may serve as esophageal cancer early detection marker, such as methylation of HIN1, TFPI-2, DACH1, and SOX17. CHFR methylation is a late stage event in ESCC and is a sensitive marker for taxanes in human ESCC. FHIT methylation is associated with poor prognosis in ESCC. Aberrant DNA methylation changes may serve as diagnostic, prognostic, and chemo-sensitive markers. Characterization of the DNA methylome in ESCC will help to better understand its mechanisms and develop improved therapies.

The clinicopathological significance and drug target potential of FHIT in breast cancer, a meta-analysis and literature review.

FHIT is a bona fide tumor-suppressor gene and its loss contributes to tumorigenesis of epithelial cancers including breast cancer (BC). However, the association and clinicopathological significance between FHIT promoter hypermethylation and BC remains unclear. The purpose of this study is to conduct a meta-analysis and literature review to investigate the clinicopathological significance of FHIT methylation in BC. A detailed literature search was performed in PubMed, EMBASE, Web of Science, and Google Scholar databases. The data were extracted and assessed by two reviewers independently. Odds ratios with 95% corresponding confidence intervals were calculated. A total of seven relevant articles were available for meta-analysis, which included 985 patients. The frequency of FHIT hypermethylation was significantly increased in invasive ductal carcinoma compared to benign breast disease, the pooled odds ratio was 8.43, P<0.00001. The rate of FHIT hypermethylation was not significantly different between stage I/II and stage III/IV, odds ratio was 2.98, P=0.06. In addition, FHIT hypermethylation was not significantly associated with ER and PR status. FHIT hypermethylation was not significantly correlated with premenopausal and postmenopausal patients with invasive ductal carcinoma. In summary, our meta-analysis indicated that the frequency of FHIT hypermethylation was significantly increased in BC compared to benign breast disease. The rate of FHIT hypermethylation in advanced stages of BC was higher than in earlier stages; however, the difference was not statistically significant. Our data suggested that FHIT methylation could be a diagnostic biomarker of BC carcinogenesis. FHIT is a potential drug target for development of demethylation treatment for patients with BC.

Quantitative detection of methylation of FHIT and BRCA1 promoters in the serum of ductal breast cancer patients.

The development of carcinoma has been found to be associated with epigenetic modifications. The aim of this study was to estimate the methylation levels of FHIT and BRCA1 promoters using the bisulphite sequencing method (BSP) and high-resolution melting curve analysis (HRM) in the serum of patients with ductal breast carcinoma as a biomarker for the possible application of early diagnosis of breast cancer. The results showed that the methylation levels of both BRCA1 and FHIT promoters were higher in the serum of the breast ductal carcinoma group (BDC group) than those of the breast fibroadenoma group (BFA group), and the healthy individuals group (HI group). However, the methylation levels of the BRCA1 promoters were very low in all three groups compared to the levels of FHIT. The advanced quantitative detection of the samples with HRM showed that the FHIT promoter methylation level of the cfDNA in each serum was also very high in the BDC group compared to the HI group. The methylation level of FHIT was found to be significantly associated with breast cancer (p < 0.05). In conclusion, the methylation quantitative detection of FHIT promoter in serum may be useful for the early diagnosis of ductal breast carcinoma.

Aberrant gene promoter methylation of p16, FHIT, CRBP1, WWOX, and DLC-1 in Epstein-Barr virus-associated gastric carcinomas.

Alterations in global DNA methylation and specific regulatory gene methylation are frequently found in cancer, but the significance of these epigenetic changes in EBV-associated gastric carcinoma (EBVaGC) remains unclear. We evaluated global DNA methylation status in 49 EBVaGC and 45 EBV-negative gastric carcinoma (EBVnGC) tissue samples and cell lines by 5-methylcytosine immunohistochemical staining and methylation quantification. We determined promoter methylation status and protein expression for the p16, FHIT, CRBP1, WWOX, and DLC-1 genes in tissues and studied the correlation between CpG island methylator phenotype (CIMP) class and clinicopathological characteristics. Changes in gene methylation and mRNA expression in EBVaGC cell line SNU-719 and in EBVnGC cell lines SGC-7901, BGC-823, and AGS were assessed after treatment with 5-aza-2'-deoxycytidine (5-aza-dC), trichostatin A (TSA), or a combination of both, by methylation-specific PCR and quantitative real-time RT-PCR. Global genomic DNA hypomethylation was more pronounced in EBVnGC than in EBVaGC. Promoter methylation of all five genes was more frequent in EBVaGC than in EBVnGC (p<0.05). p16 and FHIT methylation was reversely correlated with protein expression in EBVaGC. Most (41/49) EBVaGC exhibited CIMP-high (CIMP-H), and the prognosis of CIMP-H patients was significantly worse than that of CIMP-low (p=0.027) and CIMP-none (p=0.003) patients. Treatment with 5-aza-dC and/or TSA induced upregulation of RNA expression of all five genes in SNU-719; meanwhile, individual gene expression increased in EBVnGC cell lines. In summary, EBV-induced hypermethylation of p16, FHIT, CRBP1, WWOX, and DLC-1 may contribute to EBVaGC development. Demethylation therapy may represent a novel therapeutic strategy for EBVaGC.

Abstract 265: Early life exposure to air pollution and promoter methylation in breast tumors in the Western New York Exposures and Breast Cancer Study

Abstract Background: It has been hypothesized that early life exposures are important in establishing DNA methylation patterns and that these changes may be a mechanism for alteration in breast cancer risk. We previously found an association of exposure to total suspended particulates (TSP) in early life and breast cancer risk among post-menopausal women. Particulate matter and secondhand smoke (SHS) have been associated with aberrant DNA methylation. To our knowledge the relation between early life exposure to air pollution via SHS or TSP and aberrant DNA methylation has not been examined in breast cancer tissues. Purpose: We investigated the association between breast tumor DNA methylation in the promoter regions for 11 genes and exposure to TSP at the time of birth and SHS before age 20. We hypothesized that these exposures lead to hypermethylation of tumor suppressor genes in breast cancer tumor tissue in post-menopausal cases. Methods: A case-case study design, utilizing breast cancer cases participating in the WEB Study, a large population-based case-control study, was used to investigate our hypotheses. Five hundred and four archived tumor blocks from breast cancer cases were retrieved, DNA was extracted and methylation of 11 genes (SFN, ESR1, GSTP1, RASSF1, RARB, SYK, SCGB3A1, CDKN2A, CCND2, BRCA1, and FHIT ) was assayed with pyrosequencing. TSP exposure at birth address was estimated with ArcGIS 8.0 (ESRI, Inc., Redlands, CA), based on annual average TSP concentrations (1959-1997). Participants reported household SHS exposure before age 20. Hypermethylation was defined as mean methylation greater than 20%. Unconditional logistic regression was used to compute odds ratios (OR) and 95% confidence intervals, adjusted for age, estrogen receptor status and current smoking status. Results: Exposure to SHS before age 20 was associated with decreased average methylation (OR: 0.83; 95% CI: 0.50, 1.41) as was TSP exposure at birth (OR: 0.56; 95% CI: 0.29, 1.11), although these associations were imprecise. Exposure to SHS before age 20 was associated with decreased FHIT methylation (OR: 0.39; 95% CI: 0.17, 0.89). The other genes assessed showed similar inverse risk estimates and imprecision. Conclusions: While our results are necessarily preliminary, they are not consistent with our hypothesis that TSP or SHS exposure in early life is associated with DNA hypermethylation of promoter regions of genes in breast cancer tumor tissue. Inferences are complicated by several limitations. For instance, air pollution may have a stronger impact on global DNA hypomethylation. However these findings could also be attributed to low variability in exposures, relatively small sample size, or the choice of loci and genes assayed. Citation Format: Catherine Callahan, Matthew Bonner, Peter Shields, Christine Ambrosone, Daikwon Han, Jing Nie, Stephen Edge, Maurizio Trevisan, Jo L. Freudenheim. Early life exposure to air pollution and promoter methylation in breast tumors in the Western New York Exposures and Breast Cancer Study. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 265. doi:10.1158/1538-7445.AM2014-265

Combined effects methylation of FHIT, RASSF1A and RARβ genes on non-small cell lung cancer in the Chinese population.

Epigenetic modifications of tumour suppressor genes are involved in all kinds of human cancer. Aberrant promoter methylation is also considered to play an essential role in development of lung cancer, but the pathogenesis remains unclear.We collected the data of 112 subjects, including 56 diagnosed patients with lung cancer and 56 controls without cancer. Methylation of the FHIT, RASSF1A and RAR-β genes in DNA from all samples and the corresponding gene methylation status were assessed using the methylation-specific polymerase chain reaction (PCR, MSP). The results showed that the total frequency of separate gene methylation was significantly higher in lung cancer compared with controls (33.9-85.7 vs 0 %) (p<0.01).Similar outcomes were obtained from the aberrant methylation of combinations of any two or three genes (p<0.01). There was a tendency that the frequency of combinations of any two or three genes was higher in stage I+II than that in stage III+IV with lung cancer. However, no significant difference was found across various clinical stages and clinic pathological gradings of lung cancer (p>0.05).These observations suggest that there is a significant association of promoter methylation of individual genes with lung cancer risk, and that aberrant methylation of combination of any two or three genes may be associated with clinical stage in lung cancer patients and involved in the initiation of lung cancer tumorigenesis. Methylation of FHIT, RASSF1A and RARβ genes may be related to progression of lung oncogenesis.

Cross-contamination of a UROtsa stock with T24 cells--molecular comparison of different cell lines and stocks.

BackgroundUROtsa is an authentic, immortalized human urothelial cell line that is used to study the effects of metals and other toxic substances, mostly in the context of bladder cancer carcinogenesis. Unusual properties on the molecular level of a provided UROtsa cell line stock prompted us to verify its identity.MethodsUROtsa cell line stocks from different sources were tested on several molecular levels and compared with other cell lines. MicroRNA and mRNA expression was determined by Real-Time PCR. Chromosome numbers were checked and PCR of different regions of the large T-antigen was performed. DNA methylation of RARB, PGR, RASSF1, CDH1, FHIT, ESR1, C1QTNF6, PTGS2, SOCS3, MGMT, and LINE1 was analyzed by pyrosequencing and compared with results from the cell lines RT4, T24, HeLa, BEAS-2B, and HepG2. Finally, short tandem repeat (STR) profiling was applied.ResultsAll tested UROtsa cell line stocks lacked large T-antigen. STR analysis unequivocally identified our main UROtsa stock as the bladder cancer cell line T24, which was different from two authentic UROtsa stocks that served as controls. Analysis of DNA methylation patterns and RNA expression confirmed their differences. Methylation pattern and mRNA expression of the contaminating T24 cell line showed moderate changes even after long-term culture of up to 56 weeks, whereas miRNAs and chromosome numbers varied markedly.ConclusionsIt is important to check the identity of cell lines, especially those that are not distributed by major cell banks. However, for some cell lines STR profiles are not available. Therefore, new cell lines should either be submitted to cell banks or at least their STR profile determined and published as part of their initial characterization. Our results should help to improve the identification of UROtsa and other cells on different molecular levels and provide information on the use of urothelial cells for long-term experiments.

Quantitative assessment of lung cancer associated with genes methylation in the peripheral blood

ABSTRACTBackground: Lung cancer is the leading cause of cancer-related deaths worldwide due mainly to late diagnosis and poor prognosis. Aberrant promoter methylation is an important mechanism for silencing of tumor suppressor genes during carcinogenesis and a promising tool for the development of molecular biomarkers. Methods: We evaluated the p16, RASSF1A, and FHIT genes promoter methylation status in peripheral blood DNA between 200 lung cancer patients and 200 normal controls by using SYBR green-based quantitative methylation-specific PCR (qMSP). Results: There were statistically significant differences in the methylation status of p16, RASSF1A, and FHIT between the cancer cases and controls (p16: P = .008, RASSF1A: P = .038, FHIT: P = .002). When the subjects were categorized into quartiles based on the genes methylation status, the risk of lung cancer was found to increase as methylation status increased (p16: Ptrend = .002, RASSF1A: Ptrend = .014, FHIT: Ptrend = .001). When the median of methylation status was used as the cutoff between high and low methylation status, individuals with high methylation status were at a significantly higher risk of lung cancer than those with low methylation status (p16: adjusted odds ratio = 1.597, P = .028; RASSF1A: adjusted odds ratio = 1.551, P = .039; FHIT: adjusted odds ratio = 1.763, P = .008). In addition, there were no significant correlations between p16, RASSF1A, or FHIT methylation status and gender (P > .05), age (P > .05), smoking history (P > .05), histological type (P > .05), or clinical stage (P > .05). Conclusions: These results suggest that the high methylation statuses of p16, RASSF1A, or FHIT genes were associated with a significantly increased risk of lung cancer; the risk of lung cancer increased as the methylation status increased. Further investigation of their definitive usefulness in clinical practice is warranted.

Promoter methylation of DAPK1, FHIT, MGMT, and CDKN2A genes in cervical carcinoma

Aberrant DNA methylation contributes to the malignant phenotype in virtually all types of human cancer. This study explored the relationship between promoter methylation and inactivation of the DAPK1, FHIT, MGMT, and CDKN2A genes in cervical cancer. The promoter methylation of DAPK1, FHIT, MGMT, and CDKN2A was investigated by using a methylation-specific polymerase chain reaction in 53 specimens of cervical cancer (42 squamous cell carcinoma, 11 adenocarcinoma), 22 specimens of intraepithelial neoplasia tissues, and 24 control normal cervical tissue specimens. The correlation of promoter methylation with the clinicopathological features of cervical cancer was analyzed. The expressions of DAPK1, FHIT, MGMT, and CDKN2A were detected by measuring relative mRNA levels. The promoter methylation of DAPK1, FHIT, MGMT, and CDKN2A in cervical cancer vs. intraepithelial neoplasia vs. normal cervical tissue was 75.5 vs. 31.8 vs. 4.2 % (p < 0.0001), 66.0 vs. 59.1 vs. 25.0 % (p = 0.0033), 34.0 vs. 27.3 vs. 20.8 % (p = 0.76), and 17.0 vs. 31.8 vs. 8.3 % (p = 0.11), respectively. The methylation of the promoter region significantly decreased the expression of only DAPK1 (p = 0.03). The methylation rate of the DAPK1 gene promoter was significantly higher in cervical cancer tissues than in cervical intraepithelial neoplasia and normal cervical tissues. Promoter methylation may therefore lead to the inactivation of the DAPK1 gene, and may be related to the progression of cervical oncogenesis.