A novel polymorphism in CDC6 is associated with the decline in lung function of ex-smokers in COPD

High prevalence of airway obstruction and pulmonary emphysema in urothelial (renal pelvis, ureter, and bladder) cancer patients

BACKGROUND

Cigarette smoking is a major cause of COPD, with patients also presenting complications that stem from other smoking-related diseases, including urothelial cancer. However, the prevalence of COPD or airflow obstruction in urothelial cancer patients has not been well studied.

METHODS

We investigated the prevalence of airflow obstruction (FEV1/FVC < 70%) in newly diagnosed urothelial cancer patients and identified the risk factors for airflow obstruction in existing urothelial cancer patients. Additionally, we compared the characteristics of subjects who had been diagnosed with both airflow obstruction and urothelial cancer, and subjects whose airflow obstruction was discovered during health screenings.

RESULTS

A total of 217 patients were newly diagnosed with urothelial cancer during the study period at our institution. Among all patients, 210 (96.8%) underwent an evaluable lung function test, in which 38.6% (81 patients) displayed airflow obstruction defined as FEV1/FVC < 70%. In urothelial cancer patients, age, smoking index (pack-years), and BMI proved to be significant risk factors for airflow obstruction in multivariate logistic regression (p = 0.007, p < 0.0001, and p = 0.035, respectively). Gender, cancer stage, and cancer location were not significant risk factors. Patients with both airflow obstruction and urothelial cancer showed a more advanced emphysematous change than subjects presenting with airflow obstruction alone (unpaired t-test, p = 0.0003).

CONCLUSIONS

Airflow obstruction was identified in 38.6% of urothelial cancer patients. Age, smoking index (pack-years), and BMI were significant risk factors. A significantly higher emphysematous score was observed in subjects with urothelial cancer than in subjects with airway obstruction alone.

Identification of nine key genes by bioinformatics analysis for predicting poor prognosis in smoking-induced lung adenocarcinoma

Aim:

To screen and identify key genes related to the development of smoking-induced lung adenocarcinoma (LUAD).

Materials & methods:

We obtained data from the GEO chip dataset GSE31210. The differentially expressed genes were screened by GEO2R. The protein interaction network of differentially expressed genes was constructed by STRING and Cytoscape. Finally, core genes were screened. The overall survival time of patients with the core genes was analyzed by Kaplan–Meier method. Gene ontology and Kyoto encyclopedia of genes and genomes bioaccumulation was calculated by DAVID.

Results:

Functional enrichment analysis indicated that nine key genes were actively involved in the biological process of smoking-related LUAD.

Conclusion:

23 core genes and nine key genes among them were correlated with adverse prognosis of LUAD induced by smoking.

Meta-analysis of mRNA expression profiles to identify differentially expressed genes in lung adenocarcinoma tissue from smokers and non-smokers

Compared to other types of lung cancer, lung adenocarcinoma patients with a history of smoking have a poor prognosis during the treatment of lung cancer. How lung adenocarcinoma-related genes are differentially expressed between smoker and non-smoker patients has yet to be fully elucidated. We performed a meta-analysis of four publicly available microarray datasets related to lung adenocarcinoma tissue in patients with a history of smoking using R statistical software. The top 50 differentially expressed genes (DEGs) in smoking vs. non‑smoking patients are shown using heat maps. Additionally, we conducted KEGG and GO analyses. In addition, we performed a PPI network analysis for 8 genes that were selected during a previous analysis. We identified a total of 2,932 DEGs (1,806 upregulated, 1,126 downregulated) and five genes (CDC45, CDC20, ANAPC7, CDC6, ESPL1) that may link lung adenocarcinoma to smoking history. Our study may provide new insights into the complex mechanisms of lung adenocarcinoma in smoking patients, and our novel gene expression signatures will be useful for future clinical studies.

Retinoic acid receptors: from molecular mechanisms to cancer therapy

Retinoic acid (RA), the major bioactive metabolite of retinol or vitamin A, induces a spectrum of pleiotropic effects in cell growth and differentiation that are relevant for embryonic development and adult physiology. The RA activity is mediated primarily by members of the retinoic acid receptor (RAR) subfamily, namely RARα, RARβ and RARγ, which belong to the nuclear receptor (NR) superfamily of transcription factors. RARs form heterodimers with members of the retinoid X receptor (RXR) subfamily and act as ligand-regulated transcription factors through binding specific RA response elements (RAREs) located in target genes promoters. RARs also have non-genomic effects and activate kinase signaling pathways, which fine-tune the transcription of the RA target genes. The disruption of RA signaling pathways is thought to underlie the etiology of a number of hematological and non-hematological malignancies, including leukemias, skin cancer, head/neck cancer, lung cancer, breast cancer, ovarian cancer, prostate cancer, renal cell carcinoma, pancreatic cancer, liver cancer, glioblastoma and neuroblastoma. Of note, RA and its derivatives (retinoids) are employed as potential chemotherapeutic or chemopreventive agents because of their differentiation, anti-proliferative, pro-apoptotic, and anti-oxidant effects. In humans, retinoids reverse premalignant epithelial lesions, induce the differentiation of myeloid normal and leukemic cells, and prevent lung, liver, and breast cancer. Here, we provide an overview of the biochemical and molecular mechanisms that regulate the RA and retinoid signaling pathways. Moreover, mechanisms through which deregulation of RA signaling pathways ultimately impact on cancer are examined. Finally, the therapeutic effects of retinoids are reported.

Gene polymorphisms and chronic obstructive pulmonary disease

The genetic component was suggested to contribute to the development of chronic obstructive pulmonary disease (COPD), a major and growing public health burden. The present review aims to characterize the evidence that gene polymorphisms contribute to the aetiology of COPD and related traits, and explore the potential relationship between certain gene polymorphisms and COPD susceptibility, severity, lung function, phenotypes, or drug effects, even though limited results from related studies lacked consistency. Most of these studies were association studies, rather than confirmatory studies. More large-sized and strictly controlled studies are needed to prove the relationship between gene polymorphisms and the reviewed traits. More importantly, prospective confirmatory studies beyond initial association studies will be necessary to evaluate true relationships between gene polymorphisms and COPD and help individualized treatment for patients with COPD.

Updates on the COPD gene list

A genetic contribution to develop chronic obstructive pulmonary disease (COPD) is well established. However, the specific genes responsible for enhanced risk or host differences in susceptibility to smoke exposure remain poorly understood. The goal of this review is to provide a comprehensive literature overview on the genetics of COPD, highlight the most promising findings during the last few years, and ultimately provide an updated COPD gene list. Candidate gene studies on COPD and related phenotypes indexed in PubMed before January 5, 2012 are tabulated. An exhaustive list of publications for any given gene was looked for. This well-documented COPD candidate-gene list is expected to serve many purposes for future replication studies and meta-analyses as well as for reanalyzing collected genomic data in the field. In addition, this review summarizes recent genetic loci identified by genome-wide association studies on COPD, lung function, and related complications. Assembling resources, integrative genomic approaches, and large sample sizes of well-phenotyped subjects is part of the path forward to elucidate the genetic basis of this debilitating disease.

Association of dopamine-related gene alleles, smoking behavior and decline in FEV1 in subjects with COPD: findings from the lung health study

Cigarette smoking is the major risk factor for chronic obstructive pulmonary disease (COPD). Specific dopamine related gene alleles have previously been found to be associated with smoking initiation, maintenance and cessation. We investigated the association between specific dopamine related gene alleles and both change in smoking behavior and lung function change over time in individuals with mild-to-moderate COPD. Subjects included a subset of participants in the Lung Health Study (LHS), a smoking intervention study in smokers with mild to moderate COPD. Smoking status was determined and lung function performed at baseline and annually for 5 years. In post-hoc analyses, we assessed the association of the dopamine receptor (DRD2) TaqI A1(+) allele (A1A1, A1A2 genotypes) and A1(-) allele (A2A2 genotype), and the dopamine transporter (DAT) 9R(+) allele (9R9R and 9R10R genotypes) and 9R(-) allele (10R10R genotype) with both changes in smoking status and lung function in a subset of LHS subjects. No significant associations were noted between variants in these genes and success in smoking cessation. However, in exploratory analyses that did not adjust for multiple comparisons, sustained male (but not female) quitters with the DRD2 A1(-) allele and/or the DAT 9R(+) allele showed an accelerated decline in FEV(1) similar to that of continuing smokers over 5 years after quitting smoking. These preliminary findings suggest that dopamine-related genes may play a role in the progression of COPD, at least in the subset of male ex-smokers whose disease continues to progress despite sustained quitting, and warrants additional confirmatory and mechanistic studies.

Pathogenic triad in COPD: oxidative stress, protease-antiprotease imbalance, and inflammation

Patients with chronic obstructive pulmonary disease (COPD) exhibit dominant features of chronic bronchitis, emphysema, and/or asthma, with a common phenotype of airflow obstruction. COPD pulmonary physiology reflects the sum of pathological changes in COPD, which can occur in large central airways, small peripheral airways, and the lung parenchyma. Quantitative or high-resolution computed tomography is used as a surrogate measure for assessment of disease progression. Different biological or molecular markers have been reported that reflect the mechanistic or pathogenic triad of inflammation, proteases, and oxidants and correspond to the different aspects of COPD histopathology. Similar to the pathogenic triad markers, genetic variations or polymorphisms have also been linked to COPD-associated inflammation, protease–antiprotease imbalance, and oxidative stress. Furthermore, in recent years, there have been reports identifying aging-associated mechanistic markers as downstream consequences of the pathogenic triad in the lungs from COPD patients. For this review, the authors have limited their discussion to a review of mechanistic markers and genetic variations and their association with COPD histopathology and disease status.

Association between the CDC6 G1321A polymorphism and the risk of cervical cancer

INTRODUCTION

Cell division cycle protein 6 (CDC6) plays critical roles in DNA replication and carcinogenesis. The biological significance of the CDC6 G1321A polymorphism (V441I, rs13706) on cervical carcinogenesis is still unknown. Here, we examined the potential influence of this polymorphism on cell proliferation and the individual's susceptibility to cervical cancer.

METHODS

We genotyped the CDC6 G1321A polymorphism in 87 cervical cancer cases and 110 healthy female subjects. Unconditional logistic regression analysis was used to estimate the association between the genotypes and the risk of cervical cancer. The BrdU incorporation assay was applied to analyze the effect of this polymorphism on cell proliferation.

RESULTS

Compared with the GG homozygotes, the cervical cancer risk was significantly reduced in the individuals with the heterozygous AG genotype (odds ratio [OR], 0.53; 95% confidence interval [CI], 0.28-0.98; P = 0.042) or the homozygous AA genotype (OR, 0.29; 95% CI, 0.09-0.89; P = 0.030). Further stratified analyses showed that the decreased risk of cervical cancer was more evident among younger subjects (≤44 years old) with the AG or AA genotypes (OR, 0.44; 95% CI, 0.21-0.92; P = 0.029 and OR, 0.12; 95% CI, 0.03-0.61; P = 0.010, respectively). The BrdU incorporation assay showed that 293T cells transfected with CDC6-441I (1321A) had a lower proliferation rate in comparison with those transfected with CDC6-441V (1321G), although the difference did not reach statistical significance at the 0.05 level.

CONCLUSIONS

The CDC6 G1321A polymorphism may contribute to the risk of cervical cancer. Further studies with more subjects and in diverse ethnic populations are necessary to confirm the general validity of our findings.

Pharmacogenetics of chronic obstructive pulmonary disease: challenges and opportunities

Similar to other common chronic diseases, chronic obstructive pulmonary disease (COPD) is a heterogeneous disorder with multiple disease subtypes. Candidate gene studies have found genetic associations for COPD-related phenotypes that may be relevant for pharmacogenetics studies, including lung function decline and COPD exacerbations. However, few COPD pharmacogenetics studies have been completed. Most studies have focused on the role of variants in the beta(2)-adrenergic receptor gene on bronchodilator response, but the findings have been inconclusive. Candidate gene studies highlight the concept that genes for COPD susceptibility may also be relevant in COPD pharmacogenetics. Currently, there are no clinical applications of pharmacogenetics to COPD therapy, but the use of pharmacogenetics to determine initial smoking cessation therapy may be closer to clinical application.