【Abstract】 Objective To study the effects of different levels estradiol on inhibitory of tamoxifen on human mammary cancer cells(ER+) in vitro. Methods Estrogen receptor (ER) positive MCF7 human breast cancer cell line was treated by the same level of tamoxifen and different levels of estradiol in vitro. Cell proliferation was evaluated by MTT assay. Results E2 at concentrations between 1 × 10-12 mol/L to 1× 10-7 mol / L significantly stimulated the growth of MCF 7 . TAM (10 μmol/ L) inhabited the growth of MCF7 significantly. E2 at different levels may influence inhibitory of tamoxifen on MCF7 cell lines. E2 (1×10-8 mol/L) makes inhibitory of tamoxifen on MCF7 cell lines valueless.Conclusion E2 is the risk factor of breast cancer, and the concentration around breast cancer cells may influence the effects of TAM.
We determined estrogen receptor (ER), estradiol (E2) and testosterone (T) in the tissue of 50 gastric carcinomas ans 20 benign stomach diseases. The result showed that the positive rate of ER was 32.0% in gastric cancerous tissue, in which the poorly-differentiated type was higher than that of the well-differentiated type (Plt;0.05)，and still higher in BorrmannⅢ、Ⅳ types than in Borrmann Ⅰ、Ⅱ types (Plt;0.01). The determination of Er is significant for the estimation of prognosis ans endocrinal therapy after operation. E2 content showed no obvious difference betweenn gastric carcinoma, benign somach diseases ans normal gastric mucose, but T level and T/E2 ratio in gastric cancer were much higher than those in benign stomach diseases and normal gastric mucosa (Plt;0.05). IT suggested that the imbalance of E2 and T contents may related the occurence of gatric carcinoma. The E2 and T level showed no obvious difference between ER+ and ER- in gastric cancerous tissue.
ObjectiveTo investigate the effect of the estradiol hormones on biofilm formati on and structure of Staphylococcus epidermidis after breast implant surgery. MethodsThe concentration of Staphylococcus epidermidis strains ATCC35984 was adjusted to 1×107 CFU/mL or 1×108 CFU/mL, and the type strains were incubated on the surface of silica gel in 125 pmol/L estradiol suspensions to prepare bacterial biofilms model in vitro. After cultured in vitro for 4, 6, 12, 24, 48, and 72 hours, bacteria growth and biofilm formation ability were assessed by means of the XTT and crystal violet staining respectively. According to the above results, the bacterial suspension concentration was selected for experiments. The experimental concentration of Staphylococcus epidermidis ATCC35984 suspension and the concentrations of 50, 125, 250, 500 pmol/L estradiol suspensions were mixed with silica gel respectively to prepare biofilm model in vitro, no estradiol suspension served as control group. The experimental concentration of Staphylococcus epidermidis ATCC12228 suspension was used to prepare the same model in the negative control. After cultured in vitro for 4, 6, 12, 24, 48, and 72 hours, the same methods were used to assess the bacteria growth dynamics and biofilm forming ability, and the scanning electron microscope (SEM) was used to observe bacterial biofilm structure cultured on the surface of silica gel; the laser scanning confocal microscope (CLSM) was used to measure bacterial biofilm thickness on the surface of silica gel after 6, 12, and 24 hours. ResultsAccording to the results of semi quantitative detection of crystal violet stain and XTT methods, the bacterial suspension of 1×107 CFU/mL was selected for the experiment. XTT results indicated that the growth rates of ATCC12228 strain (at 4, 6, 12, 24, and 72 hours) and ATCC35984 strain (at 4, 6, 24, and 72 hours) in 125, 250, and 500 pmol/L estradiol were significantly faster than those in 0 and 50 pmol/L (P < 0.05). The growth rate of 500 pmol/L group was significantly faster than 125 and 250 pmol/L groups at 4, 6, and 72 hours (P < 0.05), and the growth rate of 250 pmol/L group was significantly faster than that of 125 pmol/L group at 72 hours (P < 0.05), but there was no significant difference between 0 and 50 pmol/L groups (P>0.05). At the same time point and same estradiol concentration, the growth rates showed no significant difference between 2 strains (P>0.05). Semi quantitative detection of crystal violet staining showed no biofilm formed in ATCC12228 strain in all estradiol concentration groups at different time points. In ATCC35984 strain, the biofilm was found at 4 hours and gradually thickened with time, reached the peak at 24 hours. After cultured for 4 and 6 hours, the biofilm of 0 pmol/L groups were significantly thicker than that of 125, 250, and 500 pmol/L groups (P < 0.05). At 12 hours, the 125 pmol/L group had the thickest biofilm, showing significant difference when compared with other groups (P < 0.05). The CLSM showed ATCC35984 biofilm thickness of 125, 250, and 500 pmol/L was significantly less than that of 0 and 50 pmol/L groups at 6 hours (P < 0.05), but difference was not significant between other groups (P>0.05). Then the thickness of the biofilm increased gradually, and the thickness of 125 pmol/L group was significantly larger than that of other concentration groups at 12 and 24 hours (P < 0.05). The SEM observation showed that the biofilm of 125 pmol/L group was denser and thicker than that of the other concentration groups at each time point. ConclusionHigh level estradiol can promote bacteria growth, biofilm formation, and biofilm maturity of Staphylococcus epidermidis.