ABSTRACT
Objective Androgen receptor ( AR) is extensively expressed in breast cancer and influences the proliferation of the malignant cells.Our study aimed to investigate the effect of AR on estrogen receptor (ER)-positive breast cancer. Methods ER-positive MCF-7 breast cells were exposed to various concentrations of agonist dihydrotestosterone ( DHT) or antagonist bicalutamide or left untreated .Then the proliferation and apoptosis of the cells were determined by MTT assay , cell counting , and flow cytometry , and the expressions of the proteins related to cell cycle regulation were detected by Western blot . Results The relative gray value of AR was significantly increased in the DHT group (1.055 ±0.020) but decreased in the bicalutamide group (0.705 ±0.010) as com-pared with the blank control (0.795 ±0.020) (both P<0.05).Flow cytometry showed that the early apoptosis rate of the breast cancer cells was markedly higher in the DHT group ([51.20 ±0.312]%) but lower in the bicalutamide group ([2.410 ±0.367]%) than in the blank control ([3.540 ±0.375]%) (both P<0 .01). In comparison with the control group , the expressions of the p53, p73 and p21 proteins in the MCF-7 cells were remarkably up-regulated in the DHT group but down-regulated in the bicalutamide group ( both P<0.05). Conclusion AR inhibits the proliferation of ER-posi-tive breast cancer cells , which suggests that it may be a potential ther-apeutic target for ER-positive breast cancer .
ABSTRACT
Aim To explore new ways for developing anticancer drugs by the separation of pigment from Fu-sarium species JN158 ( Fusarium sp JN158 ) , the iden-tification of its structure, the screening of anticancer components and the study of its partial mechanism. Methods Pigment separation was done by HPLC, structural analysis by UV, IR, NMR, the screening of anticancer activity by MTT. Western blot was used to analyze the protein expression of CyclinD1, NF-κB, VEGF in tumor cells. Results The results showed that the pigment from Fusarium produced a total of six different peaks, of which peak Ⅵ was the anthocya-nins. Its molecular weight is about 382, molecular for-mula is C17 H18 O10 . According to investigation, this pig-ment was probably a new compound, which could in-hibit the proliferation of MCF-7 cells markedly ( IC50:0.011mmol·L-1 ,P<0.05;the control medicine ube-nimex IC50:10 mmol · L-1 ) in a concentration-de-pendent manner, and had no effect on human umbilical cord intravenous endotheliocyte ( HUVEC ) . The influ-ence on the gene expression of CyclinD1, NF-κB, VEGF in MCF-7 cells varied with the concentration of this compound. The Western blot results showed that VI pigment compound inhibited CyclinD1, NF-κB, VEGF gene expression (P<0.05 or 0. 01),compared with the control group. Conclusion The Ⅵ pigment compound from Fusarium sp JN158 could inhibit MCF-7 proliferation by inhibiting CyclinD1, NF-κB, VEGF gene expression. The compound may be a promising compound against breast cancer.