Asian Science Citation Index is committed to provide an authoritative, trusted and significant information by the coverage of the most important and influential journals to meet the needs of the global scientific community.  
ASCI Database
308-Lasani Town,
Sargodha Road,
Faisalabad, Pakistan
Fax: +92-41-8815544
Contact Via Web
Suggest a Journal
 
Articles by L Yuan
Total Records ( 6 ) for L Yuan
  M Wang , W Zhang , L Yuan , G Fu , Q Wei and Z. Zhang
 

A recent genome-wide association study identified two common variants that confer susceptibility to bladder cancer. We hypothesized that these variants are associated with risk of bladder cancer in Chinese populations. We genotyped rs9642880 G>T on 8q24 and rs710521 A>G on 3q28 in a two-stage case–control study of bladder cancer to evaluate the association and further examined the expression of MYC. We found that the rs9642880 G>T, but not the rs710521 A>G polymorphism, was associated with an increased risk of bladder cancer. Compared with the rs9642880 GG genotype, the GT/TT genotypes were associated with an odds ratio of 1.65 (95% confidence interval = 1.25–2.17), and this risk was more pronounced in young men and for low-risk tumors. Additional experiments revealed that the rs9642880 GT/TT genotypes were associated with enhanced levels of both MYC mRNA and protein in bladder tissues. Our findings suggested that the rs9642880 G>T polymorphism on 8q24 was independently associated with the risk of bladder cancer in Chinese populations.

  S Wang , J Tang , M Wang , L Yuan and Z. Zhang
 

Recently, two genome-wide association studies identified a significant association between the prostate stem cell antigen (PSCA) rs2294008 (C>T) polymorphism and risk of diffuse-type of gastric cancer in Asians and bladder cancer in Caucasians, respectively. PSCA has been reported highly expressed in bladder cancer and been considered as a useful marker for diagnosis and progression of bladder cancer. To determine whether rs2294008 polymorphism is associated with risk of bladder cancer in Chinese populations, we conducted a hospital-based case–control study of 581 cases and 580 controls. Sixteen normal bladder tissues adjacent to tumors were used to evaluate the functionality of this polymorphism. We genotyped the rs2294008 polymorphism and assessed its association with risk of bladder cancer and messenger RNA (mRNA) expression in normal bladder tissues. A significant increased risk of bladder cancer was found for rs2294008 CT/TT genotypes (adjusted odds ratio, 1.38; 95% confidence interval, 1.09–1.75) compared with the CC genotype. Furthermore, analysis of PSCA mRNA expression identified a clear correlation of rs2294008 with expression levels of PSCA mRNA. These results indicated that the rs2294008 polymorphism of PSCA gene may play a role in bladder cancer carcinogenesis and it could be served as a biomarker for genetic susceptibility to bladder cancer in Chinese populations.

  W Zhu , C. M Trivedi , D Zhou , L Yuan , M. M Lu and J. A. Epstein
 

Rationale: Cardiac hypertrophy occurs in response to a variety of extrinsic and intrinsic stimuli that impose increased biomechanical stress. The phosphatidylinositol 3-kinase (PI3K)/Akt pathway has previously been strongly associated with hypertrophic signaling in the heart, and with the control of cell size in multiple contexts. This pathway is tightly regulated by many factors, including a host of kinases and phosphatases that function at multiple steps in the signaling cascade. For example, the PTEN (phosphatase and tensin homolog) tumor suppressor protein is a phosphoinositide 3-phosphatase that, by metabolizing phosphatidylinositol 3,4,5-trisphosphate (PtdIns[3,4,5]P3, PIP3), acts in direct antagonism to growth factor–stimulated PI3K. Inhibition of PTEN leads to cardiomyocyte hypertrophy. Another polyphoinositide phosphatase, inositol polyphosphate-5-phosphatase F (Inpp5f) has recently been implicated in regulation of cardiac hypertrophy. Like PTEN, this phosphatase can degrade PtdIns(3,4,5)P3 and thus modulates the PI3K/Akt pathway.

Objective: To characterize the role of Inpp5f in regulating cardiac hypertrophy.

Methods and Results: We generated homozygous Inpp5f knockout mice and cardiac specific Inpp5f overexpression transgenic mice. We evaluated their hearts for biochemical, structural and functional changes. Inpp5f knockout mice have augmented hypertrophy and reactivation of the fetal gene program in response to stress when compared to wild-type littermates. Furthermore, cardiac overexpression of Inpp5f in transgenic mice reduces hypertrophic responsiveness.

Conclusions: Our results suggest that Inpp5f is a functionally important endogenous modulator of cardiac myocyte size and of the cardiac response to stress.

  Y Zhang , S Li , L Yuan , Y Tian , J Weidenfeld , J Yang , F Liu , A. L Chokas and E. E. Morrisey
 

Cardiomyocyte proliferation is high in early development and decreases progressively with gestation, resulting in the lack of a robust cardiomyocyte proliferative response in the adult heart after injury. Little is understood about how both cell-autonomous and nonautonomous signals are integrated to regulate the balance of cardiomyocyte proliferation during development. In this study, we show that a single transcription factor, Foxp1, can control the balance of cardiomyocyte proliferation during development by targeting different pathways in the endocardium and myocardium. Endocardial loss of Foxp1 results in decreased Fgf3/Fgf16/Fgf17/Fgf20 expression in the heart, leading to reduced cardiomyocyte proliferation. This loss of myocardial proliferation can be rescued by exogenous Fgf20, and is mediated, in part, by Foxp1 repression of Sox17. In contrast, myocardial-specific loss of Foxp1 results in increased cardiomyocyte proliferation and decreased differentiation, leading to increased myocardial mass and neonatal demise. We show that Nkx2.5 is a direct target of Foxp1 repression, and Nkx2.5 expression is increased in Foxp1-deficient myocardium. Moreover, transgenic overexpression of Nkx2.5 leads to increased cardiomyocyte proliferation and increased ventricular mass, similar to the myocardial-specific loss of Foxp1. These data show that Foxp1 coordinates the balance of cardiomyocyte proliferation and differentiation through cell lineage-specific regulation of Fgf ligand and Nkx2.5 expression.

  L Yuan and C. R. Morales
 

Prosaposin, the precursor of four lysosomal cofactors required for the hydrolysis of sphingolipids, is transported to the lysosomes via the alternative receptor, sortilin. In this study, we identified a specific domain of 17 amino acids within the C terminus of prosaposin involved in binding to this sorting receptor. We generated six prosaposin deletion constructs and examined the effect of truncation by coimmunoprecipitation and confocal microscopy. The experiments revealed that the first half of the prosaposin C terminus (aa 524–540), containing a saposin-like motif, was required and necessary to bind sortilin and to transport it to the lysosomes. Based on this result, we introduced twelve site-directed point mutations within the first half of the C terminus. Although the interaction of prosaposin with sortilin was pH dependent, the mutation of hydrophilic amino acids that usually modulate pH-dependent protein interactions did not affect the binding of prosaposin to sortilin. Conversely, a tryptophan (W530) and two cysteines (C528 and C536) were essential for its interaction with sortilin and for its transport to the lysosomes. In conclusion, our investigation demonstrates that a saposin-like motif within the first half of the prosaposin C terminus contains the sortilin recognition site. (J Histochem Cytochem 58:287–300, 2010)

  Y Xu , L Yuan , J Mak , L Pardanaud , M Caunt , I Kasman , B Larrivee , R del Toro , S Suchting , A Medvinsky , J Silva , J Yang , J. L Thomas , A. W Koch , K Alitalo , A Eichmann and A. Bagri
 

If neuropilin-2 and the growth factor VEGF-C don’t come together, lymphatic vessels don’t branch apart.

 
 
 
Copyright   |   Desclaimer   |    Privacy Policy   |   Browsers   |   Accessibility