RASSF1A Gene Research Articles

DNA methylation analysis in plasma for early diagnosis in lung adenocarcinoma.

Lung adenocarcinoma (LUAD) represents the most prevalent type of lung cancer. SHOX2 and RASSF1A methylation have been identified as important biomarkers for diagnosis and prognosis of lung cancer. Bronchoalveolar lavage fluid (BALF) exhibits good specificity and sensitivity in diagnosing pulmonary diseases, but its acquisition is challenging and may cause discomfort to patients. In clinical, plasma samples are more convenient to obtain than BALF; however, there is little research on the concurrent detection of SHOX2 and RASSF1A methylation in plasma. This study aims to assess the diagnostic value of a combined promoter methylation assay for SHOX2 and RASSF1A in early-stage LUAD using plasma samples. BALF and blood samples were obtained from 36 early-stage LUAD patients, with a control group of nineteen non-tumor individuals. The promoter methylation levels of SHOX2 and RASSF1A in all subjects were assessed using the human SHOX2 and RASSF1A gene methylation kit. The methylation detection rate of SHOX2 and RASSF1A in plasma was 61.11%, slightly lower than that in BALF (66.7%). The Chi-square test revealed no significant difference in the methylation rate between BALF and plasma (P > 0.05). The area under the receiver operating characteristic (ROC) curve analysis for blood was 0.806 (95% CI, 0.677 to 0.900), while for BALF it was 0.781 (95% CI, 0.649 to 0.881). Additionally, we conducted an analysis on the correlation between SHOX2 and RASSF1A methylation levels in plasma with gender, age, tumor differentiation, pathologic classification, and other clinicopathological variables; however, no significant correlations were observed. Measurement of SHOX2 and RASSF1A methylation for early diagnosis of LUAD can be achieved with high sensitivity and specificity by using plasma as a substitute for BALF samples.

Promoter methylation status of RASSF1A and RASSF2A tumor suppressor genes in endometrial endometrioid carcinomas

We aimed to investigate the promoter methylation status of RASSF1A and RASSF2A tumor suppressor genes in endometrial endometrioid carcinomas with p53 wild type and mismatch repair proficient. Genomic DNAs were isolated from 50 specimens (15 formalin-fixed paraffin embedded tumor tissues, 15 paired blood samples and 20 normal endometrial tissues). Bisulfide modification and methylation-specific polymerase chain reaction were performed. As a result of the study, while no significance was found for RASSF1A gene (p = 0.08), a statistically significance was found for RASSF2A gene (p < 0.001), RASSF2A gene methylation status was also found higher in high grade tumors, advanced age (≥50) and nonsmokers groups. Our results indicate that RASSF2A gene may play a role in the carcinogenesis of endometrioid and it could be potential biomarker for early detection for endometrioid carcinoma. Further and larger investigations are needed to confirm our results.

Specific CpG sites methylation is associated with hematotoxicity in low-dose benzene-exposed workers

Benzene is a broadly used industrial chemicals which causes various hematologic abnormalities in human. Altered DNA methylation has been proposed as epigenetic biomarkers in health risk evaluation of benzene exposure, yet the role of methylation at specific CpG sites in predicting hematological effects remains unclear. In this study, we recruited 120 low-level benzene-exposed and 101 control male workers from a petrochemical factory in Maoming City, Guangdong Province, China. Urinary S-phenylmercapturic acid (SPMA) in benzene-exposed workers was 3.40-fold higher than that in control workers (P < 0.001). Benzene-induced hematotoxicity was characterized by reduced white blood cells counts and nuclear division index (NDI), along with an increased DNA damage and urinary 8-hydroxy-2′-deoxyguanosine (all P < 0.05). Methylation levels of TRIM36, MGMT and RASSF1a genes in peripheral blood lymphocytes (PBLCs) were quantified by pyrosequencing. CpG site 6 of TRIM36, CpG site 2, 4, 6 of RASSF1a and CpG site 1, 3 of MGMT methylation were recognized as hot CpG sites due to a strong correlation with both internal exposure and hematological effects. Notably, integrating hot CpG sites methylation of multiple genes reveal a higher efficiency in prediction of integrative damage compared to individual genes at hot CpG sites. The negative dose–response relationship between the combined methylation of hot CpG sites in three genes and integrative damage enabled the classification of benzene-exposed individuals into high-risk or low-risk groups using the median cut-off value of the integrative index. Subsequently, a prediction model for integrative damage in benzene-exposed populations was built based on the methylation status of the identified hot CpG sites in the three genes. Taken together, these findings provide a novel insight into application prospect of specific CpG site methylation as epi-biomarkers for health risk assessment of environmental pollutants.

Novel DNA methylation biomarkers for early diagnosis of oral tongue squamous cell carcinoma (OTSCC).

Oral tongue squamous cell carcinoma (OTSCC) is the most common malignancy type among males across the world. However, analysis of molecular markers could be useful in detecting the early-stage OTSCC, which would allow optimal clinical treatments and prolong the survival rate of patients consequently. The study has the objective of detecting the role of salivary biomarkers based on gene promoter hypermethylation. Sample data from 45 OTSCC and normal groups were analyzed to exhibit the methylation levels of salivary biomarkers (TRH, FHIT, MGMT, p16, and RASSF1A). The specificity and sensitivity analysis of methylation biomarkers was conducted in addition to the receiver operating characteristic (ROC) curve for both early-stage and advanced OTSCC stages. Quantitative data findings showed the perfect sensitivity and specificity for TRH, MGMT, p16, and RASSF1A with 100%, and > 90%, respectively. In addition, the results indicated an inefficient area under curves (> 0.7) for these biomarkers to detect the OTSCC. There were no significant differences observed between TRH and FHIT and p16 and MGMT based on the Wilcoxon signed-rank test. The methylation statuses of genes TRH, RASSF1A, p16, and MGMT might become utilized as predictive biomarkers for clinical application in early diagnosis of OTSCC and noninvasive oral cancer screening.

Evaluating the comprehensive diagnosis efficiency of lung cancer, including measurement of SHOX2 and RASSF1A gene methylation

Methylation of the promoters of SHOX2 and RASSF1A (LungMe®) exhibits promise as a potential molecular biomarker for diagnosing lung cancer. This study sought to assess the aberrant methylation of SHOX2 and RASSF1A in broncho-exfoliated cells (BEC) and compare it with conventional cytology, histology examination, immunohistochemistry, and serum tumor markers to evaluate the overall diagnostic efficiency for lung cancer. This study recruited 240 patients, including 185 malignant cases and 55 benign cases. In our observation, we noted a slight reduction in the detection sensitivity, however, the ΔCt method exhibited a significant enhancement in specificity when compared to Ct judgment. Consequently, the ΔCt method proves to be a more appropriate approach for interpreting methylation results. The diagnostic sensitivity of cytology and histology was in ranged from 20.0%-35.1% and 42.9%-80%, respectively, while the positive detection rate of LungMe® methylation ranged from 70.0% to 100%. Additionally, our findings indicate a higher prevalence of SHOX2( +) among patients exhibiting medium and high expression of Ki67 (P < 0.01), as opposed to those with low expression of Ki67, but RASSF1A methylation did not show this phenomenon (P = 0.35). Furthermore, CEA, SCCA, and CYFRA21-1 showed positive detection rates of 48.8%, 26.2%, and 55.8%, respectively. Finally, we present a comprehensive lung cancer diagnostic work-up, including LumgMe® methylation. The combined analysis of SHOX2 and RASSF1A methylation serves as a powerful complement and extension to conventional methods, enhancing the accuracy of a lung cancer diagnosis with satisfactory sensitivity and specificity.

Expression of RASSF1A, DIRAS3, and AKAP9 Genes in Thyroid Lesions: Implications for Differential Diagnosis and Prognosis of Thyroid Carcinomas.

Thyroid carcinoma is the primary endocrine malignancy worldwide. The preoperative examination of thyroid tissue lesion is often unclear. Approximately 25% of thyroid cancers cannot be diagnosed definitively without post-surgery histopathological examination. The assessment of diagnostic and differential markers of thyroid cancers is needed to improve preoperative diagnosis and reduce unnecessary treatments. Here, we assessed the expression of RASSF1A, DIRAS3, and AKAP9 genes, and the presence of BRAF V600E point mutation in benign and malignant thyroid lesions in a Polish cohort (120 patients). We have also performed a comparative analysis of gene expression using data obtained from the Gene Expression Omnibus (GEO) database (307 samples). The expression of RASSF1A and DIRAS3 was decreased, whereas AKAP9's was increased in pathologically changed thyroid compared with normal thyroid tissue, and significantly correlated with e.g., histopathological type of lesion papillary thyroid cancer (PTC) vs follicular thyroid cancer (FTC), patient's age, tumour stage, or its encapsulation. The receiver operating characteristic (ROC) analysis for the more aggressive FTC subtype differential marker suggests value in estimating RASSF1A and AKAP9 expression, with their area under curve (AUC), specificity, and sensitivity at 0.743 (95% CI: 0.548-0.938), 82.2%, and 66.7%; for RASSF1A, and 0.848 (95% CI: 0.698-0.998), 54.8%, and 100%, for AKAP9. Our research gives new insight into the basis of the aggressiveness and progression of thyroid cancers, and provides information on potential differential markers that may improve preoperative diagnosis.

Novel strategy for activating gene expression through triplex DNA formation targeting epigenetically suppressed genes.

Triplex DNA formation is a useful genomic targeting tool that is expected to have a wide range of applications, including the antigene method; however, there are fundamental limitations in its forming sequence. We recently extended the triplex DNA-forming sequence to methylated DNA sequences containing 5mCG base pairs by developing guanidino-dN, which is capable of recognizing a 5mCG base pair with high affinity. We herein investigated the effect of triplex DNA formation using TFOs with guanidino-dN on methylated DNA sequences at the promoter of the RASSF1A gene, whose expression is epigenetically suppressed by DNA methylation in MCF-7 cells, on gene expression. Interestingly, triplex DNA formation increased the expression of the RASSF1A gene at the transcript and protein levels. Furthermore, RASSF1A-activated MCF-7 cells exhibited cell growth suppressing activity. Changes in the expression of various genes associated with the promotion of apoptosis and breast cancer survival accompanied the activation of RASSF1A in cells exhibited antiproliferative activity. These results suggest the potential of increases in gene expression through triplex DNA formation as a new genomic targeting tool.

SEPT9, H4C6, and RASSF1A methylation in nasopharyngeal swabs: A reflection of potential minimally invasive biomarkers for early screening of nasopharyngeal cancer.

The potential value of epigenetic DNA methylation in early cancer screening has been demonstrated. Therefore, in this study, we performed QMS-PCR and quantitative reverse transcription PCR on the genes RASSF1A, H4C6, SEPT9, GSTP1, PAX1, SHOX2, and SOX2, which are common in epithelial cancers. We found hypermethylation in RASSF1A, H4C6 and SEPT9. The mRNA expressions of RASSF1A, H4C6 and SEPT9 in tumor group were significantly different from those in the inflammatory group and healthy group (P < .05). Receiver operating characteristic (ROC) analysis showed that the area under the curve (AUC) of RASSF1A, H4C6 and SEPT9 genes were 0.831, 0.856 and 0.767, respectively. The areas under the AUC curve of SEPT9 + H4C6, SEPT9 + RASSF1A and H4C6 + RASSF1A are 0.946, 0.912 and 0.851, respectively. The diagnostic ability of dual gene combination is better than that of single gene combination, among which SEPT9 and H4C6 combination has the best diagnostic effect. In conclusion, our findings suggest that H4C6, RASSF1A, and SEPT9 methylation occur more frequently in nasopharyngeal carcinoma, and their detection in nasopharyngeal swabs may be a minimally invasive tool for diagnosis of nasopharyngeal carcinoma.

Clinical significance of tumor suppressor genes methylation in circulating tumor DNA of patients with pancreatic cancer

BackgroundCirculating tumor DNA (ctDNA) has emerged as a potential diagnostic and prognostic biomarker in various tumors. However, the role of tumor suppressor genes (TSGs) methylation in ctDNA of patients with pancreatic cancer (PC) remains largely unclear. MethodsPatients with PC (n = 43), pancreatic benign diseases (n = 39), and healthy controls (n = 20) were enrolled in the study. Quantitative analysis of methylation pattern of five candidate TSGs including NPTX2, RASSF1A, EYA2, p16, and ppENK in ctDNA was performed by next generation sequencing (NGS). The diagnostic performances of these 5-TSGs methylation were assessed by the operating characteristic (ROC) curve and clinicopathological features correlation analysis. Meanwhile, the changes in methylation levels of these 5-TSGs on the 7th postoperative day were evaluated in 23 PC patients who underwent radical resection. ResultsThe methylation levels of RASSF1A, EYA2, ppENK and p16 genes in patients with PC were significantly higher than those in healthy controls. EYA2, p16 and ppENK genes showed significantly hypermethylation in PC than those in pancreatic benign diseases. NPTX2, RASSF1A, EYA2, p16 and ppENK genes showed significantly hypermethylation in pancreatic benign diseases than those in healthy controls (P < 0.05). The methylation levels of these 5 candidate TSGs were not correlated with the tumor size, nerve invasion, lymph node metastasis and TNM stage of PC. The AUC of these biomarkers for diagnosis of PC ranged from 0.65 to 0.96. The AUC values of these methylated genes and CpG sites for differentiating malignant and benign pancreatic diseases were ranging from 0.68 to 0.92. Combined the hypermethylated genes improved the detective ability of PC than single gene. The methylation levels of NPTX2, EYA2 and ppENK genes were significantly decreased after radical resection of PC. ConclusionQuantitative analysis of methylation pattern of NPTX2, RASSF1A, EYA2, p16 and ppENK in ctDNA by NGS could be a valuable non-invasive tool for detection and monitoring of PC.

The relationship between methylation of tumor suppressor genes &lt;i&gt;APC&lt;/i&gt;, &lt;i&gt;GSTP1&lt;/i&gt;, &lt;i&gt;RASSF1A&lt;/i&gt; and content of prostate-specific antigen- associated markers in prostate cancer diagnosis

Despite the improvement of prostate cancer (PCa) diagnostic methods and the introduction of prostate-specific antigen (PSA) monitoring, the incidence of advanced PCa in Russia remains high. New more informative variables are needed for the effective diagnosis of early stage and high-grade PCa. In the field of epigenetics of special interest is the detection of DNA hypermethylation, which can serve as a PCa biomarker, since it is common to find and may induce a stable appropriate gene silencing, leading to significant cell changes. Aim of the study was to analyze the relationship between methylation of the APC, GSTP1 and RASSF1A genes and total PSA and prostate health index (PHI) in PCa. Material and methods. The present study included 54 patients with suspicion of PCa, up to 75-years old, who had an initial total PSA level from 2.5 to 10 ng/ml. To calculate PHI value the concentrations of total PSA, free PSA and pre-mature form of PSA ([–2]proPSA) in blood serum were measured by chemiluminescence immunoassay. Results and discussion. The study has revealed the statistically significant correlation between the degree of methylation in blood plasma samples and biopsy material of only the GSTP1 gene and PSA-associated markers. We found an increase of parameters contingency as Gleason score increased. Conclusions. As a result of this work, statistically significant direct correlations were identified between changes in methylation patterns of the promoter region of the GSTP1 gene and PHI, which allows us to consider them as potential candidates for inclusion in a diagnostic panel for more effective early detection of prostate cancer.

Circulating free DNA integrity index and promoter methylation of tumor suppressor gene P16, DAPK and RASSF1A as a biomarker for oropharyngeal squamous cell carcinoma.

Circulating free DNA (cfDNA) is in use for the non-invasive diagnosis of tumors. Methylation of tumor suppressor genes (TSGs) is an early event in carcinogenesis and may serve as tumor biomarker. We have investigated cfDNA integrity and methylation of tumor suppressor genes P16, DAPK and RASSF1A in serum cfDNA of oropharyngeal squamous cell carcinoma (OPSCC) comparing paired serum and tumor tissue samples to evaluate their diagnostic use. Prospective case-control study, paired serum and tissue samples from 56 OPSCC, and 15 normal controls (NC). Sybr green Quantitate real time PCR was used for cfDNA quantification through amplification ALU 115 and 247 fragments. Promoter methylation of was analyzed in paired samples using methylation specific PCR. There was significantly high cfDNA integrity in OPSCC compared to normal control (p=<0.0001). The cfDNA integrity values were significantly higher and associated with nodal status (p=0.016). The AUC for cfDNA integrity was 0.967. The P16, DAPK and RASSF1 promoters were significantly hypermethylated in serum of OPSCC compared to NC with high concordance in tissue (up to 96.55%). The gene promoter methylation of P16 was associated with smoking (p=0.030), RASSF1A with stage (p=0.011). The combination of ALU115 with cfDNA integrity and combination of gene methylation increases diagnostic sensitivity. In followup samples the cfDNA change was not different. Liquid biopsy approach including cfDNA integrity, methylation profiling in cfDNA, in combination or separately can assist in the diagnosis of OPSCC along with radio diagnostic scan. Serum changes represent changes in tissue with very high concordance.

Diagnostic value of SHOX2, RASSF1A gene methylation combined with CEA level detection in malignant pleural effusion

AimTo investigate the diagnostic value of combined detection of SHOX2 and RASSF1A gene methylation with carcinoembryonic antigen (CEA) level in diagnosing malignant pleural effusion.MethodsBetween March 2020 and December 2021, we enrolled 68 patients with pleural effusion admitted to the Department of Respiratory and critical care medicine of Foshan Second People's Hospital. The study group included 35 cases of malignant pleural effusion and 33 cases of benign pleural effusion. Methylation of the short homeobox 2 genes (SHOX2) and RAS-related region family 1A gene (RASSF1A) in pleural effusion samples were detected by real-time fluorescence quantitative PCR, and the level of carcinoembryonic antigen (CEA) in pleural effusion samples was detected by immune flow cytometry fluorescence quantitative chemiluminescence.ResultsSHOX2 or RASSF1A gene methylation was detected in 5 cases in the benign pleural effusion group and 25 patients in the malignant pleural effusion group. The positive rate of SHOX2 or RASSF1A gene methylation in the malignant pleural effusion group was significantly higher than in the benign pleural effusion group (71.4% vs. 15.2%, P < 0.01). Positive CEA (CEA > 5 ng/m) was detected in 1 case in the benign pleural effusion group and 26 patients in the malignant pleural effusion group. The CEA-positive rate in the malignant pleural effusion group was significantly higher than in the benign pleural effusion group (74.3% vs. 3%, P < 0.01). When SHOX2 and RASSF1A gene methylation was combined with CEA detection, 6 cases were positive in the benign pleural effusion group, and 31 patients were positive in the malignant pleural effusion group. The positive rate of combined detection in the malignant pleural effusion group was significantly higher than in the benign pleural effusion group (88.6% vs. 18.2%, P < 0.01). The sensitivity, specificity, accuracy, positive predictive value, negative predictive value, and Youden’s index of SHOX2, RASSF1A gene methylation combined with CEA in diagnosing malignant pleural effusion were 88.6%, 81.8%, 85.3%, 83.8%, 87.1% and 0.7 respectively.ConclusionThe combined detection of SHOX2 and RASSF1A gene methylation with CEA level in pleural effusion has a high diagnostic value for malignant pleural effusion.

A comprehensive diagnostic scheme of morphological combined molecular methylation under bronchoscopy.

Methylated SHOX2 and RASSF1A genes are potential biomarkers for lung cancer diagnosis. Therefore, we explored the role of methylation detection combined with morphological bronchoscopic evaluation for lung cancer diagnosis. Bronchoscopy, methylation outcome, and pathological data were collected from 585 patients with lung cancer and 101 controls. The methylation status of the SHOX2 and RASSF1A genes were detected using real-time polymerase chain reaction quantification. Further, the sensitivity and area under the receiver operating characteristic curve of the three methods were analyzed. Among 686 patients, 57.1% had new lesions detected through bronchoscopy and 93.1% of these patients were diagnosed with malignant tumors. Besides, 42.9% of patients had no visible changes under bronchoscopy but there were still 74.8% of them diagnosed with malignant tumors. Bronchoscopy revealed that lung adenocarcinoma, lung squamous cell carcinoma, and small cell lung cancer mainly occurred in the upper and middle lobes. The sensitivity and specificity of methylation detection were 72.8% and 87.1% (vs. cytology 10.4% & 100%), respectively. Therefore, methylated SHOX2 and RASSF1A genes may be promising tumor markers in lung cancer diagnosis. Methylation detection can be an excellent supplementary tool for cytological diagnosis and, combined with bronchoscopy, could form a more effective diagnostic process.

Differential methylation of DNA promoter sequences in peripheral blood mononuclear cells as promising diagnostic biomarkers for colorectal cancer.

Previous reports have indicated that the methylation profile in peripheral blood mononuclear cells (PBMCs) in different genes and loci is altered in colorectal cancer (CRC). Regarding the high mortality rate and silent nature of CRC, screening and early detection can meaningfully reduce disease-related deaths. Therefore, for the first time, we aimed to evaluate the early non-invasive diagnosis of CRC via quantitative promoter methylation analysis of RUNX3 and RASSF1A genes in PBMCs. In the present study, we analyzed the methylation status of two important tumor suppressor genes including RUNX3 and RASSF1A in 70 CRC patients and 70 non-malignant subjects using methylation-quantification of endonuclease-resistant DNA (MethyQESD), and a bisulfite conversion-independent method. RUNX3 was significantly hypermethylated in PBMCs of CRC patients compared to healthy controls (P < 0.001). By determining the efficient cutoff value, the sensitivity, and specificity of RUNX3 promoter methylation for CRC diagnosis reached 84.28% and 77.14%, respectively. The receiver operating characteristic (ROC) curve analyses demonstrated that RUNX3 promoter methylation has high accuracy (areas under the curve [AUC] = 0.840, P < 0.001) for discriminating CRC subjects from healthy individuals. Moreover, RUNX3 methylation levels in PBMCs progressively increased with the stage of the disease (P < 0.001). Although the amount of RASSF1A promoter methylation was not significantly different between CRC patients and controls as well as in different stages of the disease (P > 0.05). Our findings confirmed that PBMCs are reliable sources of methylation analysis for CRC screening, and RUNX3 promoter methylation can be used as a promising biomarker for early diagnosis of CRC.

Variability of the HCV core region and host genetic and epigenetic factors can predict the response to pegylated interferon/ribavirin therapy in genotype 1b hepatitis C patients from Serbia

Variations in the hepatitis C virus (HCV) core sequence have been related to disease progression and response to antiviral therapy. Previously we showed that the methylation status of RASSF1A and p16 genes, and IL28B genotypes affects the response to pegylated interferon/ribavirin (PEG-IFN/RBV) therapy. Herein we investigated whether amino acid (aa) substitutions in the HCV core region alone or in combination with IL28B genotypes and RASSF1A/p16 methylation affect the response to PEG-IFN/RBV therapy and liver disease progression. Among 29 examined patients, we found no association between single aa substitutions and response to therapy. However, we observed that patients with the HCV core aa substitution at position 75 and CT/TT IL28B genotypes were non-responders (NR), (P=0.023). Moreover, these patients had unmethylated RASSF1A. In contrast, most patients (75%) with aa substitutions at position 91 and CC IL28B genotype achieved sustained virologic response (SVR), (P=0.030), and 70% of them had methylated RASSF1A gene. Our results suggest that combined analysis of aa substitutions in the core protein, the IL28B rs12979860 polymorphism, and the methylation status of the RASSF1A gene may help in predicting treatment response to PEG-IFN/RBV in genotype 1b chronic hepatitis C patients.

Electrochemiluminescence of Polymer Dots Featuring Thermally Activated Delayed Fluorescence for Sensitive DNA Methylation Detection.

Polymer dots (Pdots) as electrochemiluminescence (ECL) emitters have drawn intensive attention for expanding the application of ECL analytical technology. Here we used a donor-acceptor polymer with thermally activated delayed fluorescence (TADF) property as a precursor to design and synthesize a kind of highly efficient Pdots with desirable annihilation and co-reactant ECL behaviors. The TADF Pdots possessed a highly stable negative-charged state in the ECL process, and their ECL emission followed the "S-route", thus achieving theoretically 100% excitons harvesting for radiative decay. With S2O82- or tripropylamine as the co-reactant, the TADF Pdots exhibited intensive bandgap ECL emission and possessed ultrahigh ECL efficiency, which were superior to conventional fluorescent Pdots due to the TADF property and the shielding of oxygen quenching effect toward triplet excitons. By combining the stable cathodic ECL property of TADF Pdots with rolling circle amplification reaction, a sensitive ECL biosensor was designed for DNA methylation detection with RASSF1A gene fragment as a target model, which showed detection limits down to the fM level and realized the localization of the methylation site on target DNA based on steric hindrance effect. This work revealed the great potential of TADF emitters in ECL efficiency elevation and offered a new idea for the development of detection kits to quantitatively detect gene methylation.

Role of Methylated RASSF1A Gene as a potential biomarker in the diagnosis of lung cancer

Role of Methylated RASSF1A Gene as a potential biomarker in the diagnosis of lung cancer

Role of RASSF1-A gene in early detection of colorectal carcinogenesis

Background: Colorectal cancer (CRC) is a malignant neoplasm originating from the un-controlled cell proliferations in epithelial cells lining of rectum, colon, or appendix. RASSFs wereconcerned in tumourigenesis and numerous members of family are presently supposed to be tumour suppressor, Aim and objectives: Estimate- function of RASSF1-A methylated gene in theCRC pathogenesis, detect RASSF1-A methylated gene cutoff value for diagnosis and using RASSF1-A gene as abio-marker to detect recurrence after surgery, Subjects and methods: This is a prospective observational case-control researchperformed on 50 cases diagnosed as CRC by endoscopy and histopathology and 50 control persons at Aswan university hospital and internal medicine department., Results: there is high significant relation between RASSF 1A and development of colorectal-cancer, Conclusion: Genetical mutations in the Kras genes and epigenetic modifications in RASSF1-A, FHIT and MGMT genes in sporadic CRC are accompanying with the generalprogress of the disorder and can be utilized as diagnostical or prognostically biomarkers in this collection of tumours.

The Role of TSHR, PTEN and RASSF1A Promoters' Methylation Status for Non-Invasive Detection of Papillary Thyroid Carcinoma.

Aim: We investigated whether a difference exists between TSHR, PTEN and RASSF1A methylation status in plasma of subjects with papillary thyroid cancer (PTC). Methods: Peripheral blood samples were collected from 68 patients with PTC and 86 healthy controls (HC). Thyroid cancer tissue and corresponding adjacent normal tissue methylation levels were analyzed. DNA methylation level changes in TSHR, PTEN and RASSF1A genes were analyzed by quantitative methylation-sensitive polymerase chain reaction. Results: We observed that the methylation level of TSHR was significantly higher in the thyroid cancer tissue compared to adjacent normal tissue (p = 0.040). TSHR methylation levels in the PTC group plasma samples were significantly higher compared to HC (p = 0.022). After surgery, PTC plasma samples showed lower TSHR and PTEN methylation levels compared to the levels before surgery (p = 0.003, p = 0.031, respectively). The TSHR methylation level was significantly higher in PTC with larger tumor size (>2 cm) (p < 0.001), and lymph node metastases (p = 0.01), lymphovascular invasion (p = 0.02) and multifocality (p = 0.013) 0ROC analysis revealed that the TSHR methylation level provides high accuracy in distinguishing PTC from HC (p = 0.022, AUC of 0.616). Conclusion: TSHR methylation in peripheral blood samples is expected to be a sensitive and specific minimally invasive tool for the diagnosis of PTC, especially in combination with other diagnostic means.

Cromolyn chitosan nanoparticles reverse the DNA methylation of RASSF1A and p16 genes and mitigate DNMT1 and METTL3 expression in breast cancer cell line and tumor xenograft model in mice

BackgroundDeveloping epigenetic drugs for breast cancer (BC) remains a novel therapeutic approach. Cromolyn is a mast cell stabilizer emerging as an anticancer drug; its encapsulation in chitosan nanoparticles (CSNPs) improves its effect and bioavailability. However, its effect on DNA and RNA methylation machineries has not been previously tackled. MethodsThe possible anticancer effect of cromolyn CSNPs and its potential as an epigenetic drug was investigated in vitro using MCF-7 human BC cell line and in vivo using Ehrlich ascites carcinoma-xenograft model in mice symbolizing murine mammary adenocarcinoma. Mice were injected with a single dose of Ehrlich ascites carcinoma cells subcutaneously for the induction of tumor mass, and then randomized into three groups: control, cromolyn CSNPs (equivalent to 5 mg cromolyn/kg, i.p.) and plain CSNPs twice/week for 2 weeks. ResultsCromolyn CSNPs showed prominent anticancer effect in MCF-7 cells by reducing the cell viability percent and enhancing DNA damage in the comet assay demonstrating its apoptotic actions. Mechanistically, cromolyn CSNPs influenced potential epigenetic processes through mitigating DNA methyltransferase 1 (DNMT1) expression, reversing the hypermethylation pattern of the tumor suppressor RASSF1A and p16 genes and attenuating the expression of the RNA N6-methyladenosine writer, methyltransferase-like 3 (METTL3). Cromolyn CSNPs diminished ERK1/2 phosphorylation, a possible arm influencing DNMT1 expression. In vivo, cromolyn CSNPs lessened the tumor volume and halted DNMT1 and METTL3 expression in Ehrlich carcinoma mice. ConclusionsCromolyn CSNPs have the premise as an epigenetic drug through inhibiting ERK1/2 phosphorylation/DNMT1/DNA methylation and possibly impacting the RNA methylation machinery via mitigating METTL3 expression.