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Abstract Background A cross-talk between different receptor tyrosine kinases (RTKs) plays an important role in the pathogenesis of human cancers. Methods Both NIH-Met5 and T24-Met3 cell lines harboring an inducible human c-Met gene were established. C-Met-related RTKs were screened by RTK microarray analysis. The cross-talk of RTKs was demonstrated by Western blotting and confirmed by small interfering RNA (siRNA) silencing, followed by elucidation of the underlying mechanism. The impact of this cross-talk on biological function was demonstrated by Trans-well migration assay. Finally, the potential clinical importance was examined in a cohort of 65 cases of locally advanced and metastatic bladder cancer patients. Results A positive association of Axl or platelet-derived growth factor receptor-alpha (PDGFR-α) with c-Met expression was demonstrated at translational level, and confirmed by specific siRNA knock-down. The transactivation of c-Met on Axl or PDGFR-α in vitro was through a ras- and Src-independent activation of mitogen-activated protein kinase/extracellular signal-regulated kinase (MEK/ERK) pathway. In human bladder cancer, co-expression of these RTKs was associated with poor patient survival (p < 0.05), and overexpression of c-Met/Axl/PDGFR-α or c-Met alone showed the most significant correlation with poor survival (p < 0.01). Conclusions In addition to c-Met, the cross-talk with Axl and/or PDGFR-α also contributes to the progression of human bladder cancer. Evaluation of Axl and PDGFR-α expression status may identify a subset of c-Met-positive bladder cancer patients who may require co-targeting therapy.

Endothelial nitric oxide synthase (eNOS) modulates vascular blood pressure and is predominantly expressed in endothelial cells and activated through the protein kinase B (Akt/PKB)-dependent pathway. We previously reported that 3-methylcholanthrene (3MC) activates the aryl hydrocarbon receptor (AhR) and reduces PI3K/Akt phosphorylation. This study investigated the mechanism underlying the downregulatory effects of 3-MC on nitric oxide (NO) production occurring through the AhR/RhoA/Akt-mediated mechanism. The mechanism underlying the effects of 3-MC on eNOS activity and blood pressure was examined in vitro and in vivo through genetic and pharmacological approaches. Results indicated that 3-MC modified heat shock protein 90 (HSP90), caveolin-1, dynein, and eNOS mRNA and protein expression through the AhR/RhoA-dependent mechanism in mouse cerebral vascular endothelial cells (MCVECs) and that 3-MC reduced eNOS phosphorylation through the AhR/RhoA-mediated inactivation of Akt1. The upregulation of dynein expression was associated with decreased eNOS dimer formation (eNOS dimer; an activated form of the enzyme). Coimmunoprecipitation assay results indicated that 3-MC significantly reduced the interaction between eNOS and its regulatory proteins, including Akt1 and HSP90, but increased the interaction between eNOS and caveolin-1. Immunofluorescence and Western blot analysis revealed that 3-MC reduced the amount of membrane-bound activated eNOS, and a modified Griess assay revealed that 3-MC concomitantly reduced NO production. However, simvastatin reduced 3-MC-mediated murine hypertension. Our study results indicate that AhR, RhoA, and eNOS have major roles in blood pressure regulation. Statin intervention might provide a potential therapeutic approach for reducing hypertension caused by 3-MC. J. Cell. Physiol. 232: 1020-1029, 2017. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Increasing evidence suggests that PRMT5, a protein arginine methyltransferase, is involved in tumorigenesis. However, no systematic research has demonstrated the cell-transforming activity of PRMT5. We investigated the involvement of PRMT5 in tumor formation. First, we showed that PRMT5 was associated with many human cancers, through statistical analysis of microarray data in the NCBI GEO database. Overexpression of ectopic PRMT5 per se or its specific sh RNA enhanced or reduced cell growth under conditions of normal or low concentrations of serum, low cell density, and poor cell attachment. A stable clone that expressed exogenous PRMT5 formed tumors in nude mice, which demonstrated that PRMT5 is a potential oncoprotein. PRMT5 accelerated cell cycle progression through G1 phase and modulated regulators of G1; for example, it upregulated cyclin-dependent kinase ( CDK) 4, CDK6, and cyclins D1, D2 and E1, and inactivated retinoblastoma protein ( Rb). Moreover, PRMT5 activated phosphoinositide 3-kinase ( PI3K)/ AKT and suppressed c- Jun N-terminal kinase ( JNK)/c- Jun signaling cascades. However, only inhibition of PI3 K activity, and not overexpression of JNK, blocked PRMT5-induced cell proliferation. Further analysis of PRMT5 expression in 64 samples of human lung cancer tissues by microarray and western blot analysis revealed a tight association of PRMT5 with lung cancer. Knockdown of PRMT5 retarded cell growth of lung cancer cell lines A549 and H1299. In conclusion, to the best of our knowledge, we have characterized the cell-transforming activity of PRMT5 and delineated its underlying mechanisms for the first time. [ABSTRACT FROM AUTHOR]

F-box proteins, components of SCF ubiquitin-ligase complexes, are believed to be responsible for substrate recognition and recruitment in SCF-mediated proteolysis. F-box proteins that have been identified to function in the SCF complexes to date mostly have substrate-binding motifs, such as WD repeats or leucine-rich repeats in their C termini. However, many F-box proteins lack recognizable substrate-binding modules; whether they can function in the SCF complexes remains unclear. We show here that Fbx7, an F-box protein without WD repeats and leucine-rich repeats, is required for the proteasome-mediated proteolysis of the hepatoma upregulated protein (HURP). Depletion of Fbx7 by small interfering RNA leads to depression of HURP ubiquitination and accumulation of HURP abundance. In the SCFFbx7 complex, Fbx7 recruits HURP through its Cterminal proline-rich region in a Cdk1-cyclin B-phosphorylation dependent manner. Mutation of the multiple Cdk1-cyclin B phosphorylation sites on HURP or the proline-rich region of Fbx7 abolishes the association between Fbx7 and HURP. Thus, Fbx7 is a functional adaptor of the SCF complex with a proline-rich region as the substrate-binding module. In addition to Fbx7, data base analyses reveal two putative mammalian proline-rich region-containing F-box proteins, KIAA1783 and RIKEN cDNA 2410015K21. Taken together, these findings further expound the diverse substrate-recognition abilities of the SCF complexes. [ABSTRACT FROM AUTHOR]

Although the electronic medical record (EMR) has been applied extensively, the sharing and exchange of medical records between hospitals are still very difficult because of the variety of the size of hospitals and the absence of a standard form for clinical records. As the network technology is developed fast, constructing standardized forms and modules for medical information exchange becomes a necessary beside the numerous services provided by any hospitals. For the purpose of the development of the medical informatics in Taiwan, the Department of Health Executive Yuan initiated a project in 2004 for establishing a standard template of medical record and unified medical vocabulary. The project also put forward the preferential order of carrying out for which levels that the EMR standard template. In this research, we used the idea of Delphi Method to assemble an expert decision-working group, 11 experts in the domain of nursing care were enrolled. The experts were from different clinical agencies including medical centers and regional hospitals. They had one meeting every month from November 2004 to March 2005. We analyzed 869 nursing data fields, defined 33 record modules, and created six forms (or templates) including Vital Signs, Nursing Assessment, Nursing Intervention, Nursing Diagnosis, Care Plan, and Nursing Record of electronic nursing care. The standard templates have been used as the carrier of the nursing information exchange. XML structured documents were created to build a web-based EMR prototype system. After that, HTML-based documents were transformed to support the functions of data querying and downloading from the patients and clinical institutes using the interface of Web browser. [ABSTRACT FROM AUTHOR]

Colorectal cancer is one of the most common cancers with the second highest mortality rate in the world. The microarray can be used to collect gene expression alteration information from many tissue samples that will be useful to understand colorectal cancer from the molecular level. However, the mechanism behind the progression from normal to cancer is not fully understood. Here, a cross-platform comparison among three common microarray platforms (Affymetrix, Agilent, and Illumina) was applied. As results, we found a significant correlation of purine metabolism and p53 signaling pathway role in colorectal cancer progression. Purine metabolism can control the regulation of cell proliferation which involve hydro-lyase activity on organelle lumen. Meanwhile, genetic alterations in p53 signaling pathways could control some hallmarks of cancer. These two terms might play important roles in inducing normal colorectal cells into cancer.

The estrogen receptor alpha gene (ESR1) is an important mediator of the atheroprotective effect of estrogen on the vasculature system. We examined the potential associations between common single nucleotide polymorphism (SNP) variants of ESR1 and intima-media thickness (IMT) in carotid arteries, a strong predictor of cardiovascular disease (CVD). A total of 760 study participants (343 men and 407 women), who had undergone a Duplex ultrasonographic examination of carotid artery, were investigated. Measurement of IMT was performed on a 10-mm segment of the common carotid artery (CCA). Fourteen sequence-validated SNPs of high frequency of Oriental origin were selected and genotyped by the method of Light-Cycler-480-assisted real-time polymerase chain reaction (PCR) followed by melting curve analysis. Results from multiple linear regression analyses showed significant associations of SNPs rs2228480 (Ex8+229G>A) and rs3798758 (Ex8+1988C>A) with the carotid IMT values in women but not in men. Women with SNP rs2228480 (Ex8+229G>A) A/A genotype had a 0.048 mm (7.1%) increase in IMT values versus the other genotypes combined (P = .030). In women who carried the rs3798758 (Ex8+1988C>A) CA+AA combined genotypes, their carotid IMT measures were 0.020 mm (2.9%) decreased as compared with those in women who carried C/ C genotype (P = .042). In haplotype analysis, women with the T-A haplotype versus C-C haplotype of combined rs3798577 (Ex8+1264T>C) and rs3798758 (Ex8+1988C>A) were also found to be associated with a decreased IMT value at a borderline significance (P = .057). Some common SNPs in the ESR1 could be important in modulating carotid atherosclerosis and thereby CVD susceptibility in Taiwanese women.