Effects of phytoestrogen alpha-zearalanol on normal human breast / 中国医学科学院学报

<p><b>OBJECTIVE</b>To study the effects of phytoestrogen alpha-zearalanol (alpha-ZAL) on normal human breast.</p><p><b>METHODS</b>Ten specimens of normal human breast tissues were subcutaneously implanted into 30 athymic nude mice aged 9-10 weeks, one for 3 mice. These mice were then randomly divided into three groups: control group (without hormone treatment, n = 10), 1 mg/kg alpha-ZAL group (n = 10), and 5 mg/kg alpha-ZAL group (n = 10). All breast tissues were taken out 6 weeks later. Immunohistochemistry was used to determine the protein expressions of proliferating cell nuclear antigen (PCNA), inhibiting apoptosis gene Bcl-2, estrogen receptor (ER), and progesterone receptor (PR). Reverse transcription polymerase chain reaction (RT-PCR) was used to measure the expression levels of estrogen sulfotransferase (EST) mRNA and bridging integrator protein-1 (BIN1) mRNA. Morphological features of grafts before and after treatment were also observed.</p><p><b>RESULTS</b>Alpha-ZAL had no significant effects on Bcl-2, PCNA, ER, and PR expression of mammary epithelial cells in graft specimens. Alpha-ZAL upregulated BIN1 mRNA expression in grafts, but had no significant effect on ESTmRNA expression.</p><p><b>CONCLUSIONS</b>Alpha-ZAL does not affect the morphology, proliferating, and apoptosis of epithelial cells in normal human breast tissues implanted into nude mice, but it may increase the gene expression of tumor-inhibiting BIN1, suggesting that alpha-ZAL may have potential proteotive effect on normal human breast.</p>

The effect of estrogen benzoate on normal human breast tissue implanted into athymic nude mice / 中国医学科学院学报

<p><b>OBJECTIVE</b>To investigate the proliferating effect of estradiol benzoate on normal human breast tissue.</p><p><b>METHODS</b>Three specimens of normal human breast tissue were implanted into nine 9-10-week-old intact female athymic nude mice which were randomly divided into group A, B and C. Each specimen was divided into three parts, and each part was implanted into mice of each group of three (A, B and C) respectively. Two weeks later, part of xenografts was taken out from group A as control group, and then group A, B and C were injected muscularly with 3, 6, 9 micrograms estradiol benzoate once daily, respectively. After therapy for 28 days, the grafts were taken out and expression of proliferating cell nuclear antigen (PCNA), estrogen receptor (ER) and proliferating receptor (PR) in grafts were examined using immunohistochemical method.</p><p><b>RESULTS</b>Compared with control group, PCNA was increased in group B and C (P < 0.05), but in group A had no significant change. ER was gradually down regulated by 3, 6 and 9 micrograms estradiol benzoate (P < 0.05); however, PR was increasingly up regulated (P < 0.05).</p><p><b>CONCLUSIONS</b>Certain dosage of estradiol benzoate has proliferating effect on normal human breast tissue.</p>