Role of TGF-β1 and its Receptors in Breast Carcinogenesis:Evaluation of Gene Expression Patterns and Clinical Implications

OBJECTIVE Transforming growth factor β1 （TGF-β1） is a multifunc- tional cytokine that may play an important role in tumor development and progression. METHODS We evaluated gene expression patterns of TGF-β1 and its receptors [transforming growth factor β type Ⅰ receptor （TβR- Ⅰ ） and transforming growth factor β type Ⅱ receptor （TβR- Ⅱ ）] in tumor tissue from patients with breast cancer or with benign breast diseases （BBD） and adjacent normal tissue from the patients with breast cancer. Included in the study were 527 breast cancer patients and 213 BBD patients who participated in the Shanghai Breast Cancer Study. RESULTS The expression levels of the TGF-β1, TβR- Ⅰ and TβR-Ⅱ genes in breast tissue were quantified using real-time PCR. TIER- Ⅱ expression in cancer tissue was decreased by over 50% as compared to either adjacent normal tissue from the same patients or benign tumor tissue from BBD patients （p〈0.001）. TGF-β1 expression was lower by approximately 20% in cancer tissue compared to adjacent normal tissue （p=0.14） or to benign tumor tissue （p=0.002）. Although TβR-Ⅰ expression was also reduced in cancer tissue compared to adjacent normal tissue, or benign tumor tissue, the magnitude of the reduction was less apparent than that for TβR- Ⅱ. Compared to patients with the lowest tertile value for TβR- Ⅱ, patients with median tertile value for TβR- Ⅱ had more favorable overall survival （HR 0.47, 95% CI 0.27-0.85） and disease-free survival （HR 0.65, 95% CI 0.39-1.06）. No apparent associations, however, were observed between TGF-β1 or TβR- Ⅰ expression and overall or disease-free survival. CONCLUSION The results from this study support the hypothesis that a decreased level of TβR-Ⅱ gene expression, and thus reduced TGF-β1 sensitivity, is related to breast tumor progression.

Mass Transport/Diffusion and Surface Reaction Process with Lattice Boltzmann

Multi-component flow with chemical reactions is a common problem in different industrial applications:the mixing chamber of a reaction injection molding(RIM)machine;the dynamics of diesel soot particles interacting with a porous-ceramic particulate filter;reactive transport in porous media;bio-chemical processes involving enzyme-catalyzed kinetics.In all these cases,mass diffusion/convection and wall or volume chemical interactions among components play an important role.In the present paper we underline the importance of diffusion/convection/reaction mechanisms in bio-chemical processes using the Lattice Boltzmann(LB)technique.The bio-application where we studied diffusion/convection/reaction mechanisms is the quorum-sensing pathway for the bio-synthesis of the AI-2,a molecule that allows the bacteria to launch a coordinated attack on a host immune system(see[9,10]for more details of the bio-application).The overall goal is to create a micro-device to screen potential drugs that inhibit AI-2 bio-synthesis.The Michaelis-Menten saturation kinetic model is implemented at the reactive surface and the results are shown in terms of two dimensionless numbers:Damkohler(Da)and Peclet(Pe)number.For high Pe number a small conversion of reactants into products is obtained at the reactive surface,but the overall flux of products is high;moreover,a fast saturation of the conversion of reactants to products is obtained for high Da numbers.The trade-off for setting the Pe and Da numbers depends on the specific application and the technologies used in the micro-device(e.g.,sensitivity of the detector,cost of reactants).