Combination Analysis of PCDHGA12 and CDO1 DNA Methylation in Bronchial Washing Fluid for Lung Cancer Diagnosis.

BACKGROUND: When suspicious lesions are observed on computer-tomography (CT), invasive tests are needed to confirm lung cancer. Compared with other procedures, bronchoscopy has fewer complications. However, the sensitivity of peripheral lesion through bronchoscopy including washing cytology is low. A new test with higher sensitivity through bronchoscopy is needed. In our previous study, DNA methylation of PCDHGA12 in bronchial washing cytology has a diagnostic value for lung cancer. In this study, combination of PCDHGA12 and CDO1 methylation obtained through bronchial washing cytology was evaluated as a diagnostic tool for lung cancer. METHODS: A total of 187 patients who had suspicious lesions in CT were enrolled. PCDHGA12 methylation test, CDO1 methylation test, and cytological examination were performed using 3-plex LTE-qMSP test. RESULTS: Sixty-two patients were diagnosed with benign diseases and 125 patients were diagnosed with lung cancer. The sensitivity of PCDHGA12 was 74.4% and the specificity of PCDHGA12 was 91.9% respectively. CDO1 methylation test had a sensitivity of 57.6% and a specificity of 96.8%. The combination of both PCDHGA12 methylation test and CDO1 methylation test showed a sensitivity of 77.6% and a specificity of 90.3%. The sensitivity of lung cancer diagnosis was increased by combining both PCDHGA12 and CDO1 methylation tests. CONCLUSION: Checking DNA methylation of both PCDHGA12 and CDO1 genes using bronchial washing fluid can reduce the invasive procedure to diagnose lung cancer.

Identification and validation of methylated PENK gene for early detection of bladder cancer using urine DNA.

BACKGROUND: Early detection of bladder cancer (BCa) offers patients a favorable outcome and avoids the need for cystectomy. Development of an accurate and sensitive noninvasive BCa diagnostic test is imperative. DNA methylation is an early epigenetic event in the development of BCa. Certain specific aberrant methylations could serve as useful biomarkers. The aim of this study was to identify methylation biomarkers for early detection of BCa. METHODS: CpG methylation microarray analysis was conducted on primary tumors with varying stages (T1-T4) and paired nontumor tissues from nine BCa patients. Bisulfite-pyrosequencing was performed to confirm the methylation status of candidate genes in tissues and urine sediments (n = 51). Among them, PENK was selected as a potential candidate and validated using an independent set of 169 urine sediments (55 BCa, 25 benign urologic diseases, 8 other urologic cancers, and 81 healthy controls) with a quantitative methylation-specific real time PCR (mePENK-qMSP). All statistical analyses were performed using MedCalc software version 9.3.2.0. RESULTS: CpG methylation microarray analysis and stepwise validation by bisulfite-pyrosequencing for tissues and urine sediments supported aberrant methylation sites of the PENK gene as potential biomarkers for early detection of BCa. Clinical validation of the mePENK-qMSP test using urine sediment-DNA showed a sensitivity of 86.5% (95% CI: 71.2 - 95.5%), a specificity of 92.5% (95% CI: 85.7 - 96.7%), and an area under ROC of 0.920 (95% CI: 0.863 - 0.959) in detecting Ta high-grade and advanced tumor stages (T1-T4) of BCa patients. Sensitivities for Ta low-grade, Ta high-grade, T1 and T2-T4 were 55.6, 83.3, 88.5, and 100%, respectively. Methylation status of PENK was not correlated with sex, age or stage, while it was associated with the tumor grade of BCa. CONCLUSIONS: In this study, we analyzed the comprehensive patterns of DNA methylation identified that PENK methylation possesses a high potential as a biomarker for urine-based early detection of BCa. Validation of PENK methylation confirms that it could significantly improve the noninvasive detection of BCa.

Colorectal cancer screening using a stool DNA-based SDC2 methylation test: a multicenter, prospective trial.

BACKGROUND: Prevention and early detection of colorectal cancer (CRC) is a global priority, with many countries conducting population-based CRC screening programs. Although colonoscopy is the most accurate diagnostic method for early CRC detection, adherence remains low because of its invasiveness and the need for extensive bowel preparation. Non-invasive fecal occult blood tests or fecal immunochemical tests are available; however, their sensitivity is relatively low. Syndecan-2 (SDC2) is a stool-based DNA methylation marker used for early detection of CRC. Using the EarlyTect™-Colon Cancer test, the sensitivity and specificity of SDC2 methylation in stool DNA for detecting CRC were previously demonstrated to be greater than 90%. Therefore, a larger trial to validate its use for CRC screening in asymptomatic populations is now required. METHODS: All participants will collect their stool (at least 20 g) before undergoing screening colonoscopy. The samples will be sent to a central laboratory for analysis. Stool DNA will be isolated using a GT Stool DNA Extraction kit, according to the manufacturer's protocol. Before performing the methylation test, stool DNA (2 µg per reaction) will be treated with bisulfite, according to manufacturer's instructions. SDC2 and COL2A1 control reactions will be performed in a single tube. The SDC2 methylation test will be performed using an AB 7500 Fast Real-time PCR system. CT values will be calculated using the 7500 software accompanying the instrument. Results from the EarlyTect™-Colon Cancer test will be compared against those obtained from colonoscopy and any corresponding diagnostic histopathology from clinically significant biopsied or subsequently excised lesions. Based on these results, participants will be divided into three groups: CRC, polyp, and negative. The following clinical data will be recorded for the participants: sex, age, colonoscopy results, and clinical stage (for CRC cases). DISCUSSION: This trial investigates the clinical performance of a device that allows quantitative detection of a single DNA marker, SDC2 methylation, in human stool DNA in asymptomatic populations. The results of this trial are expected to be beneficial for CRC screening and may help make colonoscopy a selective procedure used only in populations with a high risk of CRC. TRIAL REGISTRATION: This trial (NCT04304131) was registered at ClinicalTrials.gov on March 11, 2020 and is available at https://clinicaltrials.gov/ct2/show/NCT04304131?cond=NCT04304131&draw=2&rank=1 .

PINCH-2 presents functional copy number variation and suppresses migration of colon cancer cells by paracrine activity.

In recent years, characterization of cancer and its environment has become necessary. However, studies of the cancer microenvironment remain insufficient. Copy number variations (CNVs) occur in 40% of cancer-related genes, but few studies have reported the correlation between CNVs in morphologically normal tissues adjacent to cancer and cancer progression. In this study, we evaluated cancer cell migration and invasion according to the genetic differences between cancer tissues and their surrounding normal tissues. To study the field cancerization effect, we screened 89 systemic metastasis-related CNVs from morphologically normal tissues adjacent to colon cancers. Among these CNVs, LIM and senescent cell antigen-like domain 2 (PINCH-2) showed copy number amplification and upregulation of mRNA in the nonrelapsed group compared to the systemic relapse group. PINCH-2 expression in colon cancer cells was lower than that in normal epithelial colon cells at both the protein and mRNA levels. Suppression of PINCH-2 resulted in decreased formation of the PINCH-2-IPP (PINCH-2, integrin-linked kinase and α-parvin) complex and reciprocally increased formation of the PINCH-1-IPP complex. Although PINCH-2 expression of survival pathway-related proteins (Akt and phospho-Akt) did not change upon suppression of PINCH-2 expression, cell migration-related proteins [matrix-metalloproteinase (MMP)-9 and -11] were upregulated through autocrine and paracrine activation. Thus, PINCH-2 participates in decreased systemic recurrence by competitively regulating IPP complex formation with PINCH-1, thereby suppressing autocrine and paracrine effects on motility in colon cancer. This genetic change in morphologically normal tissue suggests a field cancerization effect of the tumor microenvironment in cancer progression.

Identification and validation of PCDHGA12 and PRRX1 methylation for detecting lung cancer in bronchial washing sample.

Bronchoscopy is a frequently used initial diagnostic procedure for patients with suspected lung cancer (LC). Cytological examinations of bronchial washing (BW) samples obtained during bronchoscopy often yield inconclusive results regarding LC diagnosis. The present study aimed to identify molecular biomarkers as a non-invasive method for LC diagnosis. Aberrant DNA methylation is used as a useful biomarker for LC. Therefore, microarray-based methylation profiling analyses on 13 patient-matched tumor tissues at stages I-III vs. non-tumor tissues were performed, and a group of highly differentially methylated genes was identified. A subsequent analysis using bisulfite-pyrosequencing with additional tissues and cell lines revealed six methylated genes [ADAM metallopeptidase with thrombospondin type 1 motif 20, forkhead box C2 (mesenchyme forkhead 1), NK2 transcription factor related, locus 5 (Drosophila), oligodendrocyte transcription factor 3, protocadherin γ subfamily A 12 (PCDHGA12) and paired related homeobox 1 (PRRX1)] associated with LC. Next, a highly sensitive and accurate detection method, linear target enrichment-quantitative methylation-specific PCR in a single closed tube, was applied for clinical validation using BW samples from patients with LC (n=68) and individuals with benign diseases (n=33). PCDHGA12 and PRRX1 methylation were identified as the best-performing biomarkers to detect LC. The two-marker combination showed a sensitivity of 82.4% and a specificity of 87.9%, with an area under the curve of 0.891. Notably, the sensitivity for small cell LC was 100%. The two-marker combination had a positive predictive value of 93.3% and a negative predictive value of 70.7%. The sensitivity was higher than that of cytology, which only had a sensitivity of 50%. The methylation status of the two-marker combination showed no association with sex, age or stage, but was associated with tumor location and histology. In conclusion, the present study showed that the regulatory regions of PCDHGA12 and PRRX1 are highly methylated in LC and can be used to detect LC in BW specimens as a diagnostic adjunct to cytology in clinical practice.

Clinical Validation of the Proenkephalin (PENK) Methylation Urine Test for Monitoring Recurrence of Non-muscle-invasive Bladder Cancer.

Background and objective: To assess the effectiveness of a urine-based proenkephalin (PENK) methylation test using linear target enrichment-quantitative methylation-specific polymerase chain reaction (mePENK test) for detection of non-muscle-invasive bladder cancer (NMIBC) recurrence compared to cytology and the NMP22 test. Methods: We first conducted a retrospective case-control study involving 54 patients with primary BC and 29 healthy individuals. We then prospectively enrolled 186 patients (January to December 2022) undergoing cystoscopy surveillance after transurethral resection of bladder tumor, of whom 59 had recurrent tumors. We analyzed voided urine samples for PENK methylation levels in urinary DNA. Cystoscopy with histology was used as the reference standard for assessing the diagnostic accuracy of the mePENK test in detecting BC recurrence. We calculated the sensitivity and specificity using receiver operating characteristic curve analysis. Survival differences were determined using the Kaplan-Meier method and Cox proportional-hazards model. A p < 0.05 was considered statistically significant. Key findings and limitations: In the case-control study, the PENK test had sensitivity of 83.3% and specificity of 100%. For NMIBC patients undergoing cystoscopy surveillance, the sensitivity was 76.3% (95% confidence interval [CI] 63.4-86.4%) and the specificity was 85% (95% CI 77.6-90.7%), outperforming cytology (sensitivity: 28.8%, 95% CI 17.8-42.1%; p < 0.001; specificity: 97.6%, 95% CI 93.2-99.5%) and the NMP22 test (sensitivity: 54.2%, 95% CI 40.7-67.2%; p = 0.016; specificity 81.9%, 95% CI 74.1-88.2%). In the high-risk group, the mePENK test had sensitivity of 89.7% (95% CI 75.8-97.1%) and a negative predictive value of 96.9%. For the group with low/intermediate risk, the sensitivity was 41.7%. In the group with negative cystoscopy, recurrence-free survival was shorter for patients with positive than for those with negative mePENK results (245 vs 503 d), with a hazard ratio of 9.4 (p < 0.001). The main study limitation is the small sample size. Conclusions and clinical implications: The mePENK test showed good performance for detection of NMIBC recurrence and has potential for use for prognosis and prediction. Patient summary: We found that a test used to analyze urine samples showed good performance in detecting recurrence of NMIBC. This noninvasive mePENK test may help in personalized follow-up care for patients with NMIBC.

EarlyTect BCD, a Streamlined PENK Methylation Test in Urine DNA, Effectively Detects Bladder Cancer in Patients with Hematuria.

The current noninvasive diagnostic approaches for detecting bladder cancer (BC) often exhibit limited clinical performance, especially for the initial diagnosis. This study aims to evaluate the validity of a streamlined urine-based PENK methylation test called EarlyTect BCD in detecting BC in patients with hematuria scheduled for cystoscopy in Korean and American populations. The test seamlessly integrates two steps, linear target enrichment and quantitative methylation-specific PCR within a single closed tube. The detection limitation of the test was approximately two genome copies of methylated PENK per milliliter of urine. In the retrospective training set (n = 105), an optimal cutoff value was determined to distinguish BC from non-BC, resulting in a sensitivity of 87.3% and a specificity of 95.2%. In the prospective validation set (n = 210, 122 Korean and 88 American patients), the overall sensitivity for detecting all stages of BC was 81.0%, with a specificity of 91.5% and an area under the curve value of 0.889. There was no significant difference between the two groups. The test achieved a sensitivity of 100% in detecting high-grade Ta and higher stages of BC. The negative predictive value of the test was 97.7%, and the positive predictive value was 51.5%. The findings of this study demonstrate that EarlyTect BCD is a highly effective noninvasive diagnostic tool for identifying BC among patients with hematuria.

Comparative detection of syndecan-2 methylation in preoperative and postoperative stool DNA in patients with colorectal cancer.

BACKGROUND: Early detection of colorectal cancer (CRC) is essential to reduce cancer-related morbidity and mortality. Stool DNA (sDNA) testing is an emerging method for early CRC detection. Syndecan-2 (SDC2) methylation is a potential biomarker for the sDNA testing. Aberrant DNA methylation is an early epigenetic event during tumorigenesis and can occur in the normal colonic mucosa during aging, which can compromise the sDNA test results. AIM: To determine whether methylated SDC2 in sDNA normalizes after surgical resection of CRC. METHODS: In this prospective study, we enrolled 151 patients with CRC who underwent curative surgical resection between September 2016 and May 2020. Preoperative stool samples were collected from 123 patients and postoperative samples were collected from 122 patients. A total of 104 samples were collected from both preoperative and postoperative patients. Aberrant promoter methylation of SDC2 in sDNA was assessed using linear target enrichment quantitative methylation-specific real-time polymerase chain reaction. Clinicopathological parameters were analyzed using the results of SDC2 methylation. RESULTS: Detection rates of SDC2 methylation in the preoperative and postoperative stool samples were 88.6% and 19.7%, respectively. Large tumor size (3 cm, P = 0.019) and advanced T stage (T3-T4, P = 0.033) were positively associated with the detection rate of SDC2 methylation before surgery. Female sex was associated with false positives after surgery (P = 0.030). Cycle threshold (CT) values were significantly decreased postoperatively compared with preoperative values (P < 0.001). The postoperative negative conversion rate for preoperatively methylated SDC2 was 79.3% (73/92). CONCLUSION: Our results suggested that the SDC2 methylation test for sDNA has acceptable sensitivity and specificity. However, small size and early T stage tumors are associated with a low detection rate of SDC2 methylation. As the cycle threshold values significantly decreased after surgery, SDC2 methylation test for sDNA might have a diagnostic value for CRC.

Evaluation of Sensitive Urine DNA-Based PENK Methylation Test for Detecting Bladder Cancer in Patients with Hematuria.

Hematuria is a prevalent symptom associated with bladder cancer (BC). However, the invasiveness and cost of cystoscopy, the current gold standard for BC diagnosis in patients with hematuria, necessitate the development of a sensitive and accurate noninvasive test. This study introduces and validates a highly sensitive urine-based DNA methylation test. The test improves sensitivity in detecting PENK methylation in urine DNA using linear target enrichment followed by quantitative methylation-specific PCR. In a case-control study comprising 175 patients with BC and 143 patients without BC with hematuria, the test's optimal cutoff value was determined by distinguishing between two groups, achieved an overall sensitivity of 86.9% and a specificity of 91.6%, with an area under the curve of 0.892. A prospective validation clinical study involving 366 patients with hematuria scheduled for cystoscopy assessed the test's performance. The test demonstrated an overall sensitivity of 84.2% in detecting 38 cases of BC, a specificity of 95.7%, and an area under the curve of 0.900. Notably, the sensitivity for detecting Ta high grade and higher stages of BC reached 92.3%. The test's negative predictive value was 98.2%, and the positive predictive value was 68.7%. These findings highlight the potential of the PENK methylation in urine DNA using linear target enrichment followed by quantitative methylation-specific PCR test in urine as a promising molecular diagnostic tool for detecting primary BC in patients with hematuria, which may reduce the need for cystoscopy.

Differential gene expression profile in PBMCs from subjects with AERD and ATA: a gene marker for AERD.

Aspirin-exacerbated respiratory disease (AERD) is associated with severe asthma and aspirin can cause asthma to worsen, often in the form of a severe and sudden attack. The oral aspirin challenge is the gold standard to confirm the diagnosis of AERD, but it is time consuming and produces serious complications in some cases. Therefore, more efficient and practical method is needed to predict AERD patients. The aim of the present study was to identify AERD-related gene expression in peripheral blood mononuclear cells (PBMCs) and examine the diagnostic potential of these candidate gene(s) for predicting AERD. To do this, RNAs from 24 subjects with AERD and 18 subjects with aspirin-tolerant asthma (ATA) were subjected to microarray analysis of ~34,560 genes. In total, 10 genes were selected as candidate gene markers by applying p ≤ 0.001(t test) and ≥8-fold change, and to correct for multiple comparisons, the false discovery rate analyses were performed. By applying multiple logistic regression analysis, among possible 1,023 models (2(10)-1), a model consisting of CNKSR3, SPTBN2, and IMPACT was selected as candidate set, because this set showed the best AUC (0.98) with 88 % sensitivity and 89 % specificity. For validation, mRNA levels by real-time PCR on PBMCs from two population sets in a gene-chip study and another replication sample, 20 AERD, 20 ATA, and 8 normal controls, were significantly different between groups with 100 % sensitivity and 100 % specificity in each of the two population sets. However, IMPACT gene did not differentiate between AERD and normal controls. The set of the two genes (CNKSR3 and SPTBN2) showed the best AUC (0.96) with 88 % sensitivity and 94 % specificity in a gene-chip study sample. In addition, this set showed perfect discriminative power with AUC (1.0, 100 % sensitivity and 100 % specificity) in each of the two population sets: the gene-chip samples and the replication samples. It also showed perfect discrimination for AERD from NC (AUC: 1.0) and ATA from NC (AUC: 1.0). In conclusion, we developed the two gene markers (CNKSR3 and SPTBN2) of PBMC which differentiate between AERD and ATA with a perfect discriminative power. These gene markers may be an efficient and practical method for predicting AERD.

Undifferentiated hematopoietic cells are characterized by a genome-wide undermethylation dip around the transcription start site and a hierarchical epigenetic plasticity.

Evidence for the epigenetic regulation of hematopoietic stem cells (HSCs) is growing, but the genome-wide epigenetic signature of HSCs and its functional significance remain unclear. In this study, from a genome-wide comparison of CpG methylation in human CD34(+) and CD34(-) cells, we identified a characteristic undermethylation dip around the transcription start site of promoters and an overmethylation of flanking regions in undifferentiated CD34(+) cells. This "bivalent-like" CpG methylation pattern around the transcription start site was more prominent in genes not associated with CpG islands (CGI(-)) than CGI(+) genes. Undifferentiated hematopoietic cells also exhibited dynamic chromatin associated with active transcription and a higher turnover of histone acetylation than terminally differentiated cells. Interestingly, inhibition of chromatin condensation by chemical treatment (5-azacytidine, trichostatin A) enhanced the self-renewal of "stimulated" HSCs in reconstituting bone marrows but not "steady-state" HSCs in stationary phase bone marrows. In contrast, similar treatments on more mature cells caused partial phenotypic dedifferentiation and apoptosis at levels correlated with their hematopoietic differentiation. Taken together, our study reveals that the undifferentiated state of hematopoietic cells is characterized by a unique epigenetic signature, which includes dynamic chromatin structures and an epigenetic plasticity that correlates to level of undifferentiation.

Pyrosequencing cut-off value identifying BRAFV600E mutation in fine needle aspiration samples of thyroid nodules.

CONTEXT: Recently, tremendous efforts have been made towards the development of sensitive techniques to detect the BRAF(V600E) mutation in fine needle aspiration biopsy (FNAB) samples. However, newly developed quantitative and semi-quantitative methods, such as dual-priming oligonucleotide (DPO)-based multiplex polymerase chain reaction (PCR), have the potential to generate false-positive (FP) results. OBJECTIVES: To eliminate the possibility of FP results, we generated a receiver operating characteristic (ROC) curve to investigate the diagnostic accuracy of pyrosequencing using quantitative data. DESIGN: Cytological diagnoses of 983 thyroid nodules were made according to the Bethesda System 2007. The BRAF(V600E) mutation was analysed by pyrosequencing, and statistical analyses were performed. RESULTS: Of the 983 nodules, 902 were adopted to evaluate the diagnostic value of pyrosequencing. The number of pathologically confirmed malignancies was 192, of which 182 were papillary thyroid cancer (PTC). By generating an ROC curve, we defined the optimal cut-off value of the mutant allele peak as 5·95% (area under the curve, 0·849; sensitivity, 0·55; 1-specificity, 0). When we applied this selective cut-off value, the number of PTCs positive for BRAF(V600E) was 99 (54·4% of the total number of PTCs). With cytology alone, the diagnostic sensitivity and specificity of detecting malignancy were 71·2% and 100%, respectively. Pyrosequencing improved the diagnostic sensitivity from 71·2% to 78·5% (McNemar's test, P < 0·001), without any change in the diagnostic specificity. When 'suspicious for malignancy' was considered a positive cytological outcome, pyrosequencing increased the diagnostic sensitivity of cytology from 95·8% to 96·9%; however, this improvement did not show statistical significance (McNemar's test, P > 0·05). CONCLUSIONS: Pyrosequencing is an effective method for detecting the BRAF(V600E) mutation in FNAB samples. By allowing the optimal cut-off value to be determined, pyrosequencing improves the diagnostic sensitivity while eliminating the possibility of FP results.

Detection of HOXA9 gene methylation in tumor tissues and induced sputum samples from primary lung cancer patients.

BACKGROUND: Lung cancer is a leading cause of cancer deaths. Unfortunately, no effective early screening modality exists for lung cancer. We aimed to evaluate the prevalence of HOXA9 promoter methylation in tissue and induced sputum samples from Korean patients with lung cancer. METHODS: Using pyrosequencing, HOXA9 methylation was analyzed for 40 pairs of primary lung cancer and normal tissues and 185 induced sputum specimens, including 76 patients with lung cancer. RESULTS: The methylation of HOXA9 in lung cancer tissue was significantly higher compared with normal tissues (67.4% ± 17.6% vs. 23.6% ± 10.3%, respectively; p<0.001). With a cut-off of >45.6% of HOXA9 gene methylation in tissues, the sensitivity was 90.5% and the specificity was 97.5%. In induced sputum specimens, the HOXA9 gene in lung cancer patients was significantly more hypermethylated compared with patients with benign lung diseases and the healthy group (23.4% ± 15.9%, 14.9% ± 7.9%, and 9.7% ± 5.0%, respectively; p<0.001). CONCLUSIONS: The HOXA9 gene was hypermethylated in 32 of 40 tumors (80%), especially in early stages of lung cancer. HOXA9 methylation could be a potential biomarker to aid early detection and prognosis.

Diagnostic value of pyrosequencing for the BRAF V600E mutation in ultrasound-guided fine-needle aspiration biopsy samples of thyroid incidentalomas.

CONTEXT: Dideoxy sequencing is the most commonly used method for detecting the BRAF(V600E) mutation in thyroid cancer and melanoma. However, this gold standard method often makes less definite results in detecting the BRAF(V600E) mutation when there are relatively low amounts of the mutant template in biopsy specimens, which are invariably contaminated with normal tissues. Pyrosequencing, which measures the incorporation of each of the four nucleotides at each template position and indicates the amounts of mutant template present, may be more useful in such situations. OBJECTIVE: To investigate the diagnostic efficiency of pyrosequencing for the mutant BRAF allele in ultrasound (US)-guided fine needle aspiration biopsies (FNABs) of thyroid incidentalomas. DESIGN, SETTING AND SUBJECTS: A total of 101 thyroid incidentaloma cases were included prospectively. Cytological diagnoses of the FNAB samples were made according to the American Thyroid Association (ATA) guidelines, 2006. The presence of the BRAF(V600E) mutation was investigated by pyrosequencing and dideoxy sequencing. RESULTS: On the basis of cytological analysis, the thyroid incidentalomas were classified into benign (n = 43), malignant (n = 30), indeterminate or suspicious neoplasm (n = 24), and nondiagnostic (n = 4) categories. Pyrosequencing detected the BRAF(V600E) mutation in 30 cases: 22 malignant cases, 7 indeterminate cases, and 1 nondiagnostic case. Dideoxy sequencing also detected the BRAF(V600E) mutation in 28 of the same cases but failed to clearly distinguish the mutant allele from the wild-type allele in one indeterminate case and one nondiagnostic case. Histopathological analysis ascertained that all BRAF(V600E)-positive cases were papillary thyroid carcinomas. CONCLUSIONS: Pyrosequencing may be suitable for detecting the BRAF(V600E) mutation in thyroid incidentaloma and may be superior to dideoxy sequencing when low amounts of the mutant template are present in the biopsy.

Early detection of colorectal cancer based on presence of methylated syndecan-2 (SDC2) in stool DNA.

BACKGROUND: Colorectal cancer (CRC) screening can effectively reduce disease-related mortality by detecting CRC at earlier stages. We have previously demonstrated that the presence of SDC2 methylation in stool DNA is significantly associated with the occurrence of CRC regardless of clinical stage. The aim of this study was to evaluate the clinical performance of stool DNA-based SDC2 methylation test for CRC. METHODS: Aberrant SDC2 methylation in stool-derived DNA was measured by linear target enrichment (LTE)-quantitative methylation-specific real-time PCR (qMSP). Duplicate reactions of meSDC2 LTE-qMSP test were performed for stool samples obtained from CRC patients representing all stages (0-IV) and asymptomatic individuals who were subsequently underwent colonoscopy examination. To determine the diagnostic value of test in CRC and control groups, sensitivity and specificity were evaluated by receiver operating characteristic curve analysis. RESULTS: Of 585 subjects who could be evaluated, 245 had CRC, 44 had various sizes of adenomatous polyps, and 245 had negative colonoscopy results. Stool DNA-based meSDC2 LTE-qMSP showed an overall sensitivity of 90.2% with AUC of 0.902 in detecting CRC (0-IV) not associated with tumor stage, location, sex, or age (P > 0.05), with a specificity of 90.2%. Sensitivity for detecting early stages (0-II) was 89.1% (114/128). This test also detected 66.7% (2/3) and 24.4% (10/41) of advanced and non-advanced adenomas, respectively. CONCLUSIONS: Results of this study validated the capability of stool DNA based-SDC2 methylation test by LTE-qMSP for early detection of CRC patient with high specificity. TRIAL REGISTRATION: ClinicalTrials.gov, NCT03146520 , Registered 10 May 2017, Retrospectively registered; however, control arm was prospectively registered.

PCDHGA12 methylation biomarker in bronchial washing specimens as an adjunctive diagnostic tool to bronchoscopy in lung cancer.

The use of bronchoscopy is central to the diagnosis of lung cancer. However, the sensitivity of bronchoscopy is low. In addition, bronchial washing cytology, which is a routine adjunctive test, does not significantly improve the performance of bronchoscopy owing to its low sensitivity. To enhance the diagnostic performance of bronchoscopy, the protocadherin GA12 (PCDHGA12) methylation biomarker in bronchial washings was introduced as a novel adjunctive diagnostic test. A total of 98 patients who underwent bronchoscopy owing to suspicion of lung cancer were analyzed. Cytological examination and PCDHGA12 methylation biomarker testing of the bronchial washing fluid were performed. The performance of the tests was analyzed. The final diagnosis in 60 patients was lung cancer and in 38 patients was benign disease. The PCDHGA12 methylation biomarker had a sensitivity of 75.0%, a specificity of 78.9% and a positive predictive value (PPV) of 84.9%, whereas cytological assessment had a sensitivity of 45.0%, a specificity of 92.1% and a PPV of 90%. Patients with positive PCDHGA12 methylation test had an odds ratio for lung cancer of 11.25 (confidence interval, 4.25-29.8) compared with negative subjects. The combination of the two tests exhibited an increased sensitivity (83.3%), a specificity of 71.1% and a PPV of 82.0%. Furthermore, considering the non-diagnostic bronchoscopy group alone, the test demonstrated a sensitivity of 61.9% and a specificity of 78.9%. The results of the present study demonstrated that PCDHGA12 methylation, as a lung cancer biomarker in bronchial washings, may be a used as an adjunctive test to bronchoscopy.

Analysis of Syndecan-2 Methylation in Bowel Lavage Fluid for the Detection of Colorectal Neoplasm.

Background/Aims: Syndecan-2 (SDC2) methylation was previously reported as a sensitive serologic biomarker for the early detection of colorectal cancer (CRC). The purpose of this study was to investigate whether SDC2 methylation is detectable in precancerous lesions and to determine the feasibility of using SDC2 methylation for the detection of CRC and precancerous lesions in bowel lavage fluid (BLF). Methods: A total of 190 BLF samples were collected from the rectum at the beginning of colonoscopy from patients with colorectal neoplasm and healthy normal individuals. Fourteen polypectomy specimens were obtained during colonoscopy. A bisulfite pyrosequencing assay and quantitative methylation-specific polymerase chain reaction were conducted to measure SDC2 methylation in tissues and BLF DNA. Results: SDC2 methylation was positive in 100% of villous adenoma (VA) and high-grade dysplasia, and hyperplastic polyp samples; 88.9% of tubular adenoma samples; and 0% of normal mucosa samples. In the BLF DNA test for SDC2 methylation, the sensitivity for detecting CRC and VA was 80.0% and 64.7%, respectively, at a specificity of 88.9%. The BLF of patients with multiple tubular adenomas, single tubular adenoma and hyperplastic polyps showed 62.8%, 26.7% and 28.6% rates of methylation-positive SDC2, respectively. Conclusions: Our results demonstrated that SDC2 methylation was a frequent event in precancerous lesions and showed high potential in BLF for detecting patients with colorectal neoplasm.

Feasibility of quantifying SDC2 methylation in stool DNA for early detection of colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) screening is the most efficient strategy to reduce disease-related mortality. Frequent aberrant DNA methylation is known to occur in selected genes and early during CRC development, which has emerged as a new epigenetic biomarker for early detection of CRC. Previously, we reported that we identified that CpG sites of SDC2 were aberrantly methylated in tumor tissues of most CRC patients through comprehensive methylation analysis and demonstrated a high potential of quantification of SDC2 methylation in blood for early detection of colorectal cancer. In this study, we aim to investigate the feasibility of quantifying SDC2 methylation in stool DNA for the early detection of CRC. The objective of this study was to confirm a high frequency of SDC2 methylation in tumor tissues at various stages of CRC and investigate the feasibility of a quantitative test for SDC2 methylation in fecal DNA by highly sensitive and accurate real-time PCR for early detection of CRC. METHODS: Bisulfite-pyrosequencing assay was performed to measure the SDC2 methylation status in tissue samples. For methylation analysis in stool DNA, a highly sensitive and accurate method was applied which implements consecutive two rounds of PCR consisting of unidirectional linear target enrichment (LTE) of SDC2 and quantitative methylation-specific real time PCR (qMSP) for SDC2, named as meSDC2 LTE-qMSP assay. Its limit of detection was 0.1% methylation (corresponding to ~ 6 copies in total ~ 6200 genome copies). RESULTS: Positive SDC2 methylation was observed in 100% of primary tumors, 90.6% of adenomatous polyps, 94.1% of hyperplastic polyps, and 0% of normal tissues. SDC2 methylation level also significantly (P < 0.01) increased according to the severity of lesions. In stool DNA test for SDC2 methylation by LTE-qMSP comparing CRC patients with various stages (I to IV) (n = 50) and precancerous lesions (n = 21) with healthy subjects (n = 22), the overall sensitivity was 90.0% for detecting CRC and 33.3% for detecting small polyps, with a specificity of 90.9%. CONCLUSIONS: Taken together, our result indicates that stool DNA-based SDC2 methylation test by LTE-qMSP is a potential noninvasive diagnostic tool for early detection of CRC.

Analysis of gene expression profiles in insulin-sensitive tissues from pre-diabetic and diabetic Zucker diabetic fatty rats.

Insulin resistance occurs early in the disease process, preceding the development of type 2 diabetes. Therefore, the identification of molecules that contribute to insulin resistance and leading up to type 2 diabetes is important to elucidate the molecular pathogenesis of the disease. To this end, we characterized gene expression profiles from insulin-sensitive tissues, including adipose tissue, skeletal muscle, and liver tissue of Zucker diabetic fatty (ZDF) rats, a well characterized type 2 diabetes animal model. Gene expression profiles from ZDF rats at 6 weeks (pre-diabetes), 12 weeks (diabetes), and 20 weeks (late-stage diabetes) were compared with age- and sex-matched Zucker lean control (ZLC) rats using 5000 cDNA chips. Differentially regulated genes demonstrating > 1.3-fold change at age were identified and categorized through hierarchical clustering analysis. Our results showed that while expression of lipolytic genes was elevated in adipose tissue of diabetic ZDF rats at 12 weeks of age, expression of lipogenic genes was decreased in liver but increased in skeletal muscle of 12 week old diabetic ZDF rats. These results suggest that impairment of hepatic lipogenesis accompanied with the reduced lipogenesis of adipose tissue may contribute to development of diabetes in ZDF rats by increasing lipogenesis in skeletal muscle. Moreover, expression of antioxidant defense genes was decreased in the liver of 12-week old diabetic ZDF rats as well as in the adipose tissue of ZDF rats both at 6 and 12 weeks of age. Cytochrome P450 (CYP) genes were also significantly reduced in 12 week old diabetic liver of ZDF rats. Genes involved in glucose utilization were downregulated in skeletal muscle of diabetic ZDF rats, and the hepatic gluconeogenic gene was upregulated in diabetic ZDF rats. Genes commonly expressed in all three tissue types were also observed. These profilings might provide better fundamental understanding of insulin resistance and development of type 2 diabetes.

Molecular mechanisms of the 2,3,7,8-tetrachlorodibenzo-p-dioxin-induced inverted U-shaped dose responsiveness in anchorage independent growth and cell proliferation of human breast epithelial cells with stem cell characteristics.

Although 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) has a variety of carcinogenic and noncarcinogenic effects in experimental animals, its role in human carcinogenicity remain controversial. A simian virus 40-immortalized cell line from normal human breast epithelial cells with stem cells and luminal characteristics (M13SV1) was used to study whether TCDD can induce AIG positive colony formation and cause increased cell numbers in a inverted U-shaped dose-response manner. TCDD activated Akt, ERK2, and increased the expression of CYP1A1, PAI-2, IL-lb mRNA, and ERK2 protein levels. TCDD was able to increased phosphorylation and expression of ERK2 in same dose-response manner as AIG positive colony formation. Thus, TCDD induced tumorigenicity in M13SV1, possibly through the phosphorylation of ERK2 and/or Akt. Further, cDNA microarray with 7448 sequence-verified clones was used to profile various gene expression patterns after treatment of TCDD. Three clear patterns could be delineated: genes that were dose-dependently up-regulated, genes expressed in either U-shape and/or inverted U-shape. The fact that these genes are intrinsically related to breast epithelial cell proliferation and survival clearly suggests that they may be involved in the TCDD-induced breast tumorigenesis.