Abnormal Expression of Adhesion Protein Bves is Associated with Gastric Cancer Progression and Poor Survival

The Popeye domain containing gene family encoding a family of cAMP-effector proteins with important functions in striated muscle and beyond

The Popeye domain containing (POPDC) gene family encodes a novel class of membrane-bound cyclic AMP effector proteins. POPDC proteins are abundantly expressed in cardiac and skeletal muscle. Consistent with its predominant expression in striated muscle, Popdc1 and Popdc2 null mutants in mouse and zebrafish develop cardiac arrhythmia and muscular dystrophy. Likewise, mutations in POPDC genes in patients have been associated with cardiac arrhythmia and muscular dystrophy phenotypes. A membrane trafficking function has been identified in this context. POPDC proteins have also been linked to tumour formation. Here, POPDC1 plays a role as a tumour suppressor by limiting c-Myc and WNT signalling. Currently, a common functional link between POPDC's role in striated muscle and as a tumour suppressor is lacking. We also discuss several alternative working models to better understand POPDC protein function.

Ten years of research on the role of BVES/ POPDC1 in human disease: a review

Since the blood vessel epicardial substance or Popeye domain-containing protein 1 (BVES/POPDC1) was first identified in the developing heart by two independent laboratories in 1999, an increasing number of studies have investigated the structure, function, and related diseases of BVES/POPDC1. During the first 10 years following the discovery of BVES/POPDC1, studies focused mainly on its structure, expression patterns, and functions. Based on these studies, further investigations conducted over the previous decade examined the role of BVES/POPDC1 in human diseases, such as colitis, heart diseases, and human cancers. This review provides an overview of the structure and expression of BVES/POPDC1, mainly focusing on its potential role and mechanism through which it is involved in human cancers.

Clinical significance of expression of olfactory receptor family 2 subfamily W member 3 in human pancreatic cancer

AIM

To examine the expression of olfactory receptor family 2 subfamily W member 3 (OR2W3) in human pancreatic cancer (PC) and to analyze its clinical significance.

METHODS

The expression of OR2W3 in 50 paraffin-embedded PC tissues and tumor adjacent tissues was detected by immunohistochemistry, and the relationship between the expression of OR2W3 protein and the clinicopathological factors was analyzed.

RESULTS

The high expression and low expression rates of OR2W3 protein in PC tissues and tumor adjacent tissues were 78% (39/50) vs 12% (6/50) and 22% (11/50) vs 88% (44/50), respectively, and the differences between them were statistically significant (χ² = 44.00, P < 0.05). Single factor analysis showed that the expression of OR2W3 was closely related to the degree of tissue differentiation, clinical stage, and lymph node metastasis of PC (P < 0.05).

CONCLUSION

Overexpression of OR2W3 may play an important role in the development and progression of PC.

Comparative pan-cancer DNA methylation analysis reveals cancer common and specific patterns

Abnormal DNA methylation is an important epigenetic regulator involving tumorigenesis. Deciphering cancer common and specific DNA methylation patterns is essential for us to understand the mechanisms of tumor development. The Cancer Genome Atlas (TCGA) project provides a large number of samples of different cancers that enable a pan-cancer study of DNA methylation possible. Here we investigate cancer common and specific DNA methylation patterns among 5480 DNA methylation profiles of 15 cancer types from TCGA. We first define differentially methylated CpG sites (DMCs) in each cancer and then identify 5450 hyper- and 4433 hypomethylated pan-cancer DMCs (PDMCs). Intriguingly, three adjacent hypermethylated PDMC constitute an enhancer region, which potentially regulates two tumor suppressor genes BVES and PRDM1 negatively. Moreover, we identify six distinct motif clusters, which are enriched in hyper- or hypomethylated PDMCs and are associated with several well-known cancer hallmarks. We also observe that PDMCs relate to distinct transcriptional groups. Additionally, 55 hypermethylated and 7 hypomethylated PDMCs are significantly associated with patient survival. Lastly, we find that cancer-specific DMCs are enriched in known cancer genes and cell-type-specific super-enhancers. In summary, this study provides a comprehensive investigation and reveals meaningful cancer common and specific DNA methylation patterns.

The Popeye domain containing genes: essential elements in heart rate control

The Popeye domain containing (Popdc) gene family displays preferential expression in skeletal muscle and heart. Only recently a significant gain in the understanding of the function of Popdc genes in the heart has been obtained. The Popdc genes encode membrane proteins harboring an evolutionary conserved Popeye domain, which functions as a binding domain for cyclic adenosine monophosphate (cAMP). Popdc proteins interact with the two-pore channel TREK-1 and enhance its current. This protein interaction is modulated by cAMP. Null mutations of members of the Popdc gene family in zebrafish and mouse are associated with severe cardiac arrhythmia phenotypes. While in zebrafish an atrioventricular block was prevalent, in mouse a stress-induced sinus bradycardia was observed, which was due to the presence of sinus pauses. Moreover, the phenotype develops in an age-dependent manner, being absent in the young animal and becoming increasingly severe, as the animals grow older. This phenotype is reminiscent of the sick sinus syndrome (SSS), which affects mostly the elderly and is characterized by the poor ability of the cardiac pacemaker to adapt the heart rate to the physiological demand. While being a prevalent disease, which is responsible for a large fraction of pacemaker implantations in Western countries, SSS is poorly understood at the molecular level. It is therefore expected that the study of the molecular basis of the stress-induced bradycardia in Popdc mice will shed new light on the etiology of pacemaker disease.