ABSTRACT
The expression and possible role of integrin-focal adhesion kinase signal pathway in invasive pituitary adenomas were explored. Forty-nine human pituitary adenomas were detected for the expression of integrinbeta1 (INTbeta1) and focal adhesion kinase (FAK) by immunohistochemistry, and their correlation with the invasiveness of pituitary adenomas as well as between themselves was analyzed. The results showed that INTbeta1 was expressed in 46 cases (93.9%) and FAK in 36 cases (73.5%), respectively, and their expression levels were highly correlated with tumor invasiveness, but not with the tumor types. It was suggested that the integrin-focal adhesion kinase signal pathway plays a role in the invasiveness of pituitary adenomas.
ABSTRACT
The expression of basic fibroblast growth factor (bFGF) and fibroblast growth factor receptor-1 (FGFR-1) in human meningiomas and the relationships between their expression and the tumors' histological features and angiogenesis were investigated by means of immunohistochemical technique. The expression of bFGF and FGFR-1 was detected by antibody of bFGF or FGFR-1.The tumors' angiogenesis was evaluated by microvascular density (MVD) and, which was observed by use of CD34-antibody immunohistochemically. The results showed that there were varied degrees of the expression of bFGF and FGFR-1 proteins in meningiomas. The expression was correlated with the tumors' histological characters and angiogenesis. It was concluded that bFGF and FGFR-1 might play important roles in meningiomas' angiogenesis and proliferation. The expression positive rate of bFGF and FGFR-1 may provide an indication of evaluating the histological and malignant degree of the tumor.
ABSTRACT
Recombinant human epidermal growth factor (rhEGF, 20 ng/ml) and Genistein (740 μmol/ml) were added to the cells from 12 cases of human pituitary tumors and co-cultured in vitro. The 3H-thymidine uptake of tumor cells was measured by scintillation counter and tyrosine kinases activity was detected by using immunocytochemical method. The results showed that 3H-thymidine uptake and tyrosine kinases activity were increased in 10 out of 12 cases of human pituitary tumor by EGF and both declined by Genistein. It was suggested that EGF had a strong mitogenic effect on majority of pituitary tumors. Genistein could abolish the effects of EGF promoting the proliferation of the tumor cells, inhibit the growth of the tumor and might be useful in pituitary tumor treatment.
ABSTRACT
Objective:To explore the mechanism of growth factor autocrine stimulation in human pituitary tumors. Method: Immunohistochemical analyses of EGF、TGF-αand EGFR were studied on paraffin-embeded sections of 30 pituitary tumors. Results: Expression of EGFR and its ligand EGF、TGF-αhas a variable stained cells intensity,density and type. EGFR and the ligands expressed in majority of pituitary tumors.Conclusion:The EGF autocrine stimulation exists in pituitary tumors,and tyrosine kinases inhibitors may be useful for pituitary tumors treatment.
ABSTRACT
Objective To explore the in vitro culture conditions for neural stem cells to differentiate into neuron-like cells.Methods Neural stem cells were induced to differentiate by a medium containing bFGF and heparin through adhesive culture.Immunohistochemistry was used to identify the expressions of NSE and GFAP after differentiation.Results Positive cells for NSE were 47.3%?1.7% on the 7th day after induction.The number of NSE positive cells in the induction group was 3 times as many as that in the control group(P
ABSTRACT
Phorbol ester-induced release of growth hormone (GH) and prolactin (PRL) from human somatotrophic tumors was examined in vitro. 12-O-tetradecanoyl-phorbol-13- acetate (TPA)strongly stimulated GH and PRL secretion and showed an additive effect on GH secretion if used in combination with GH releasing hormone (GHRH). In contrast, staurosporine exerted a variable inhibitory effect on GH release. There was no correlation between such effects and gsp mutations.The findings suggested that TPA doesn't act directly through cAMP signal transduction system.
ABSTRACT
Phorbol ester-induced release of growth hormone (GH) and prolactin (PRL) from human somatotrophic tumors was examined in vitro. 12-O-tetradecanoyl-phorbol-13- acetate (TPA)strongly stimulated GH and PRL secretion and showed an additive effect on GH secretion if used in combination with GH releasing hormone (GHRH). In contrast, staurosporine exerted a variable inhibitory effect on GH release. There was no correlation between such effects and gsp mutations.The findings suggested that TPA doesn't act directly through cAMP signal transduction system.