The expression of human epidermal growth factor receptor 2 (HER2), serine-threonine kinase (Akt), 4E-binding protein (4EBP1), phophorylated ribosomal protein S6 kinasel (p70S6Kl) and ribosomal protein S6 ( S6) were detected with immunohistochemistry in 48 cases of human breast cancer. Tumors high-expressing HER2 showed higher Akt expression as compared to tumors with negative HER2 (P < 0. 01). Levels of Akt were correlated with the downstream molecules 4EBP1 ( P < 0. 01) and p70S6K ( P < 0. 05 ). 4EBP1 was mainly expressed in poorly differentiated tumors (P <0. 01) and correlated with tumor size ( P < 0. 05) , lymph node metastasis ( P < 0. 01) and locoregional recurrences ( P < 0. 01). Results suggest that 4EBPl may be the main factor in PI-phosphoinositide-3-kinase (PI3K)-Akt-mammalian targot of rapanycin signal transduction pathways, which is associated with grade of malignancy and prognosis of breast cancer.

Objective:Sertoli cells (SCs) provide physical support and material supply for germ cells and participate in the formation of blood-testis barrier.The number of SCs is directly proportional to the number of germ cells.And mature SCs ensure the growth of germ cells and the production of sperm.In this study,we explored the effect and underlying mechanism of Lycium barbarum polysaccharides (LBP) on primary SCs in young rats.Methods:Primary SCs were isolated from the testis of 20-day old rats.The cells were then treated with different concentrations of LBP.Immunocytochemistry was used to detect the expression of Ki67 and the androgen receptor (AR),and western blotting was used to detect the expression of cytokeratin-18 (CK-18),AR and phosphorylated Akt (Ser473) in SCs.Results:The number of SCs increased significantly after LBP treatment,and the 100 mg/mL.LBP group had 14％ more cells than the control group.The expression of Ki67 in LBP treated groups also increased significantly.LBP inhibited the expression of cytokeratin 18 in SCs.Besides,LBP increased the expression of AR on SCs and promoted the activation of Akt at the set473 phosphorylation site.Conclusion:LBP promotes the proliferation of immature SCs in young rats and also accelerates their differentiation and maturation.This seems to be associated with activation of the Akt signaling pathway via up-regulation of AR.

Objective To observe the effects of tumor necrosis factor-or (TNF-α) and platelet derived growth factor (PDGF) on vascular neointimal hyperplasia on matrix metalloproteinase 9/2 gene knockout (MMP9/2-/-) mice and explore related mechanisms.Methods Mice of control group,MMP9-/-group,MMP2-/-group and MMP9/2-/-group were studied.Femoral artery was injured by transluminal wire,the mRNA expression levels of TNF-o and PDGF on femoral artery were detected by RT-PCR;the protein expression of MMP9 and MMP2 were assessed by Western blot on day 0,1,3,7,14and 28 post injury.Mice in control group received TNF-α(5 ng/ml,0.10 ml),TNF-α(0.05 ml) + MMP inhibitor SB-3CT (0.50 ng/ml,0.05 ml) injection,or PDGF-bb (10 ng/ml,0.10 ml) and PDGF-bb (0.05 ml) + SB-3CT(0.05 ml) injection around injured artery,intimal hyperplasia at 2 and 4 weeks after injury was observed.Intimal hyperplasia at 2 and 4 weeks after injury was also observed in MMP9/2-/-mice.TNF-α(5 ng/ml,0.10 ml) was injected to MMP2-/-mice,PDGF-bb (0.1 ml) was injected to MMP9-/-mice around injured artery,intimal hyperplasia at 2 and 4 weeks after injury was observed.The degree of neointimal hyperplasia were observed by the Elastica-van Gieson staining and the area of neointima and media of the arteries were measured by SigmaPlot and intima ratio was calculated.Vascular smooth muscle cell (VSMC) mediums of MMP9-/-and MMP2-/-mice were stimulated by TNF-α and PDGF-bb,respectively,and migration assay,and proliferation assay were performed,relative migration and proliferation cells numbers were counted.Results (1) mRNA expression of TNF-o (235.33 ± 23.68) and PDGF-bb (3.30 ±0.56) in femoral arteries peaked at 1 day after injury,while MMP9 or MMP2 protein expression peaked at 7 or 28 days after injury.(2) In control mice,TNF-α intervention significantly enhanced intimal hyperplasia at 2 weeks after injury (2.21 ±0.05 vs.1.55 ±0.03 in blank control group,P ＜ 0.05),while PDGF-bb intervention significantly enhanced intimal hyperplasia at 4 weeks after injury (2.60 ± 0.07 vs.1.89 ± 0.04,P =0.03).(3) Intima hyperplasia was significantly higher in control group than in MMP9/2-/-group at 2 weeks (1.63 ± 0.05 vs.0.46 ± 0.01,P =0.008) and 4 weeks (2.24 ±0.06 vs.0.51 ±0.01) after injury(P =0.005).(4) TNF-o intervention stimulated intimal hyperplasia in MMP2-/-mice (intimal ratio at 2 weeks after injury:1.73 ± 0.05 vs.1.23 ± 0.03,P =0.02) and PDGF-bb intervention stimulated intimal hyperplasia in MMP9-/-mice(intimal ratio at 4 weeks after injury:2.32 ± 0.06 vs.1.35 ± 0.03,P =0.03).(5) Reduced VSMC migration was evidenced in MMP9-/-mice post TNF-α stimulation (1.45 ±0.03 vs.2.16 ±0.04 in control group,P =0.03),while reduced VSMC proliferation post PDGF was seen in MMP2-/-group (1.15 ± 0.02 vs.1.82 ± 0.04 in control group,P =0.03).Conclusions TNF-o induced MMP9 activation plays a major role on promoting VSMC migration at the first 2 weeks after vascular injury,while PDGF induced MMP2 activation plays a crucial role on VSMC proliferation on the following 2 weeks after vascular injury in this mice model.Thus,the axis of TNF-α-MMP9-VSMC migration axis and PDGF-MMP2-VSMC proliferation axis are the two major working mechanisms responsible for intimal hyperplasia post vascular injury.