BACKGROUNDEctonucleotide pyrophosphatase/phosphodiesterase (ENPP)-1 is a membrane-bound protein that catalyzes the hydrolysis of extracellular nucleoside triphosphates to monophosphate and extracellular inorganic pyrophosphate (ePPi). Mechanical stimulation regulates ENPP-1 expression. This study sought to investigate the changes in ENPP-1 expression after stimulation using cyclic mechanical tension (CMT).

METHODSRat end-plate chondrocytes were cultured and subjected to CMT (at 3%, 6%, and 9% elongation) for 20, 40, and 60 minutes to observe changes in the expression of ENPP-1. To investigate the pathway, end-plate chondrocytes were exposed to 10 ng/ml of transforming growth factor beta 1 (TGF-β1), TGF-β1 siRNA, or a specific extracellular signalregulated kinase (ERK)1/2 inhibitor, U0126, in addition to CMT. Changes in ENPP-1 expression were measured by reverse transcription PCR (RT-PCR) and Western blotting.

RESULTSWe observed the largest increase in ENPP-1 expression following 3% elongation CMT stimulation. ENPP-1 expression was also increased when end-plate chondrocytes were exposed to 10 ng/ml of TGF-β1, but decreased after TGF-β knockdown with siRNA. ERK1/2 phosphorylation was activated after 3% elongation for 40 minutes, and the stimulatory effect of TGF-β1 on ENPP-1 mRNA and protein expression was inhibited by the suppression of the ERK1/2 pathway using U0126.

CONCLUSIONCMT increases the expression of ENPP-1 in end-plate chondrocytes in a manner likely dependent on TGF-β induction by the ERK1/2 signaling pathway.

Animals ; Blotting, Western ; Cells, Cultured ; Chondrocytes ; metabolism ; Phosphoric Diester Hydrolases ; genetics ; metabolism ; Pyrophosphatases ; genetics ; metabolism ; RNA, Small Interfering ; Rats ; Rats, Sprague-Dawley ; Reverse Transcriptase Polymerase Chain Reaction ; Signal Transduction ; Stress, Mechanical ; Transforming Growth Factor beta1 ; genetics ; metabolism

Background and Objective: Ewing's sarcoma family of tumor (ESFT)is aggressive.The optimal therapy modality for ESFT is still to be found.This study was to explore the clinicaI characteristjcs and therapy for ESFT.Methods:Ninety-two cases of ESFT were collected from January 1995 to April 2008 in Sun Yat-sen University Cancer Center and analyzed retrospectively.Result:Of 92 cases,23 were Ewing's sarcoma of bone,21 extraosseous Ewing's sarcoma,43 peripheral primitive neuroectodermal tumor,and 5 Askin tumor.Median follow-up time was 31.5 months(range,10-137months).Thirty-eight patients received multidisciplinary therapy and 19 single model therapy in non-metastasis group.Three-year overall survival (OS) and event-free survival (EFS) were significantly different between non-metastatic multidisciplinary therapy group and non-metastatic single model group(63%vs.20%.46%vs.18%,respectively,P<0.001).The patients who received surgery plus chemotherapy and plus radiation or not had longer survival than those treated with chemotherapy plus radiation in non-metastatic multidisciplinary therapy group(χ~2=7.591, 9.212;P=0.006,0.002).CAV/IE alternative regimen was superior to other regimens in event-free survival,but not in overall survival(χ~2=6.950,3.530;P=0.008,0.06).Cox regression analysis suggested therapy model and response to treatment were independent prognostic factors for ESFT.Conclusions:Our studying showed multidisciplinary therapy could significantly improve non-metastatic ESFT patients'survival.Chemotherapy plus surgery and plus radiation or not were superior to chemotherapy plus radiation in local control for the non-metastatic ESFT,Therapy model and response were independent prognostic factors.

Human bocavirus, which was firstly discovered in 2005, is a new human parvovirus associated with lower respiratory tract infection in children. In this study, a human bocavirus, named WLL-1 isolate, was identified in Wenlin County, Zhejiang Province. The genome of bocavirus WLL-1 has been sequenced and analyzed. Phylogenetic analyses showed that WLL-1 shares 99% homology with other bocaviruses recently reported, but also has some special variations.
Bocavirus ; classification ; genetics ; isolation & purification ; China ; DNA, Viral ; chemistry ; genetics ; Genome, Viral ; Humans ; Molecular Sequence Data ; Phylogeny ; Sequence Analysis, DNA