Association of promoter methylation with histologic type and pleural indentation in non-small cell lung cancer (NSCLC)

<p>Abstract</p> <p>Background</p> <p>Lung cancer is a major cause of death worldwide. Gene promoter methylation is a major inactivation mechanism of tumor-related genes, some of which can be served as a biomarker for early diagnosis and prognosis evaluation of lung cancer.</p> <p>Methods</p> <p>We determined the promoter methylation of 6 genes using quantitative methylation-specific PCR (Q-MSP) technique in 96 clinically well-characterized non-small cell lung cancer (NSCLC).</p> <p>Results</p> <p>Highly frequent promoter methylation was found in NSCLC. With 100% diagnostic specificity, high sensitivity, ranging from 44.9 to 84.1%, was found for each of the 6 genes. Our data also showed that promoter methylation was closely associated with histologic type. Most of genes were more frequently methylated in squamous cell carcinomas (SCC) compared to adenocarcinomas (ADC). Moreover, promoter methylation significantly increased the risk of pleural indentation in NSCLC.</p> <p>Conclusion</p> <p>Our findings provided evidences that multiple genes were aberrantly methylated in lung tumorigenesis, and demonstrated the promoter methylation was closely associated with clinicopathologic characteristics of NSCLC. More importantly, we first revealed promoter methylation may be served as a potentially increased risk factor for pleural indentation of NSCLC patients.</p

Concomitant hypermethylation of multiple genes in non-small cell lung cancer (NSCLC)

Primary lung cancer remains the leading cause of cancer death worldwide. Promoter hypermethylation is a major inactivation mechanism of tumor-related genes, and increasingly appears to play an important role in carcinogenesis. In the present study, we used quantitative methylation-specific PCR (Q-MSP) assays to analyze promoter hypermethylation of nine genes in a large cohort of well-characterized non-small cell lung cancer (NSCLC) and explore their associations with the clinicopathological features of tumor. We found that there were significant differences in methylation levels for six of nine gene promoters between cancerous and noncancerous lung tissues. More importantly, with 100% diagnostic specificity, high sensitivity, ranging from 44.9% to 84.1%, was found for each of the nine genes. Interestingly, promoter hypermethylation of most genes was closely associated with histologic type, which was more frequent in squamous cell carcinomas (SCC) than in adenocarcinomas (ADC). In addition, highly frequent concomitant methylation of multiple genes was found in NSCLC, particularly in SCC. Our data showed that multiple genes were aberrantly methylated in lung tumorigenesis, and that they were closely associated with certain clinicopathological features of NSCLC, particularly of the histologic type, suggesting that these hypermethylated genes could be potential biomarkers in early detection of NSCLC in high-risk individuals, as well as in evaluating the prognosis of NSCLC patients. (Folia Histochemica et Cytobiologica 2011, Vol. 49, No. 1, 132&#8211;141

Highly frequent promoter methylation and PIK3CA amplification in non-small cell lung cancer (NSCLC)

<p>Abstract</p> <p>Background</p> <p>Lung cancer is the leading cause of cancer-related death worldwide. Genetic and epigenetic alterations have been identified frequently in lung cancer, such as promoter methylation, gene mutations and genomic amplification. However, the interaction between genetic and epigenetic events and their significance in lung tumorigenesis remains poorly understood.</p> <p>Methods</p> <p>We determined the promoter methylation of 6 genes and <it>PIK3CA </it>amplification using quantitative methylation-specific PCR (Q-MSP) and real-time quantitative PCR, respectively, and explore the association of promoter methylation with <it>PIK3CA </it>amplification in a large cohort of clinically well-characterized non-small cell lung cancer (NSCLC).</p> <p>Results</p> <p>Highly frequent promoter methylation was observed in NSCLC. With 100% diagnostic specificity, excellent sensitivity, ranging from 45.8 to 84.1%, was found for each of the 6 genes. The promoter methylation was associated with histologic type. Methylation of <it>CALCA, CDH1, DAPK1</it>, and <it>EVX2 </it>was more common in squamous cell carcinomas (SCC) compared to adenocarcinomas (ADC). Conversely, there was a trend toward a higher frequency of <it>RASSF1A </it>methylation in ADC than SCC. In addition, <it>PIK3CA </it>amplification was frequently found in NSCLC, and was associated with certain clinicopathologic features, such as smoking history, histologic type and pleural indentation. Importantly, aberrant promoter methylation of certain genes was significantly associated with <it>PIK3CA </it>amplification.</p> <p>Conclusions</p> <p>Our data showed highly frequent promoter methylation and <it>PIK3CA </it>amplification in Chinese NSCLC population, and first demonstrated the associations of gene methylation with <it>PIK3CA </it>amplification, suggesting that these epigenetic events may be a consequence of overactivation of PI3K/Akt pathway.</p

Aberrant DNA methylation of drug metabolism and transport genes in nodular goiter

The genes encoding drug-metabolizing enzymes and transporters play an important role in maintaining the normal life processes of human body. Their disorder or defect will lead to the occurrence and development of various diseases. Currently, most of studies have focused on genetic variations in these genes, however, in the present study, we analyzed promoter methylation of 11 drug metabolism and transport genes in a cohort of nodular goiter and normal thyroid tissues using methylation-specific PCR (MSP). Our data first revealed a distinct methylation profiling in drug metabolism and transport genes between nodular goiter and normal thyroid tissues, particularly ABCB4, CYP1B1 and CYP24A1 and SLC1A2. Given these genes contribute to the development and progression of various diseases, such as multidrug resistance and tumorigenesis, these epigenetic events may thus play a critical role in the pathogenesis of nodular goiter

Engineered protein degradation of farnesyl pyrophosphate synthase is an effective regulatory mechanism to increase monoterpene production in Saccharomyces cerevisiae

Monoterpene production in Saccharomyces cerevisae requires the introduction of heterologous monoterpene synthases (MTSs). The endogenous farnesyl pyrosphosphate synthase (FPPS; Erg20p) competes with MTSs for the precursor geranyl pyrophosphate (GPP), which limits the production of monoterpenes. ERG20 is an essential gene that cannot be deleted and transcriptional down-regulation of ERG20 has failed to improve monoterpene production. Here, we investigated an N-degron-dependent protein degradation strategy to down-regulate Erg20p activity. Degron tagging decreased GFP protein half-life drastically to 1 h (degron K3K15) or 15 min (degrons KN113 and KN119). Degron tagging of ERG20 was therefore paired with a sterol responsive promoter to ensure sufficient metabolic flux to essential downstream sterols despite the severe destabilisation effect of degron tagging. A dual monoterpene/sesquiterpene (linalool/nerolidol) synthase, AcNES1, was used as a reporter of intracellular GPP and FPP production. Transcription of the synthetic pathway was controlled by either constitutive or diauxie-inducible promoters. A combination of degron K3K15 and the ERG1 promoter increased linalool titre by 27-fold to 11 mg L−1 in the strain with constitutive promoter constructs, and by 17-fold to 18 mg L−1 in the strain with diauxie-inducible promoter constructs. The sesquiterpene nerolidol remained the major product in both strains. The same strategies were applied to construct a limonene-producing strain, which produced 76 mg L−1 in batch cultivation. The FPPS regulation method developed here successfully redirected metabolic flux toward monoterpene production. Examination of growth defects in various strains suggested that the intracellular FPP concentration had a significant effect on growth rate. Further strategies are required to balance intracellular production of FPP and GPP so as to maximise monoterpene production without impacting on cellular growth.</p

Frequent Gene Amplification Predicts Poor Prognosis in Gastric Cancer

Gastric cancer is one of the most common malignancies worldwide. However, genetic alterations leading to this disease are largely unknown. Gene amplification is one of the most frequent genetic alterations, which is believed to play a major role in the development and progression of gastric cancer. In the present study, we identified three frequently amplified genes from 30 candidate genes using real-time quantitative PCR method, including ERBB4, C-MET and CD44, and further explored their association with clinicopathological characteristics and poor survival in a cohort of gastric cancers. Our data showed amplification of these genes was significantly associated with certain clinicopathological characteristics, particularly tumor differentiation and cancer-related death. More importantly, amplification of these genes was significantly related to worse survival, suggesting that these amplified genes may be significant predictors of poor prognosis and potential therapeutic targets in gastric cancer. Targeting these genes may thus provide new possibilities in the treatment of gastric cancer

Highly frequent PIK3CA amplification is associated with poor prognosis in gastric cancer

<p>Abstract</p> <p>Background</p> <p>The phosphoinositide 3-kinase (PI3K)/Akt pathway plays a fundamental role in cell proliferation and survival in human tumorigenesis, including gastric cancer. <it>PIK3CA </it>mutations and amplification are two major causes of overactivation of this pathway in human cancers. However, until this work, there was no sound investigation on the association of <it>PIK3CA </it>mutations and amplification with clinical outcome in gastric cancer, particularly the latter.</p> <p>Methods</p> <p>Using direct sequencing and real-time quantitative PCR, we examined <it>PIK3CA </it>mutations and amplification, and their association with clinicopathological characteristics and clinical outcome of gastric cancer patients.</p> <p>Results</p> <p><it>PIK3CA </it>mutations and amplification were found in 8/113 (7.1%) and 88/131 (67%) gastric cancer patients, respectively. <it>PIK3CA </it>amplification was closely associated with increased phosphorylated Akt (p-Akt) level. No relationship was found between <it>PIK3CA </it>mutations and clinicopathological characteristics and clinical outcome in gastric cancer. <it>PIK3CA </it>amplification was significantly positively associated with cancer-related death. Importantly, Kaplan-Meier survival curves revealed that the patients with <it>PIK3CA </it>amplification had significantly shorter survival times than the patients without <it>PIK3CA </it>amplification.</p> <p>Conclusions</p> <p>Our data showed that <it>PIK3CA </it>mutations were not common, but its amplification was very common in gastric cancer and may be a major mechanism in activating the PI3K/Akt pathway in gastric cancer. Importantly, Kaplan-Meier survival curves revealed that <it>PIK3CA </it>amplification was significantly positively associated with poor survival of gastric cancer patients. Collectively, the PI3K/Akt signaling pathway may be an effective therapeutic target in gastric cancer.</p

Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049