探讨高强度聚焦超声消融后残余子宫肌瘤组织转归的机制

Analysis on mechanism of outcome of residual uterine fibroid tissue after high intensity focused ultrasound ablation

目的分析超声消融对靶区外不同位点子宫肌瘤组织雌、孕激素受体以及芳香化酶的表达情况,探讨残余子宫肌瘤的转归的可能机制。方法采用MR引导下高强度聚焦超声(HIFU)肿瘤治疗系统消融8个子宫肌瘤,声功率400W,辐照时间60s,以MR检测靶区外子宫肌瘤组织的升温情况。治疗前取1cm×1cm子宫肌瘤组织为对照组。辐照完毕后取靶区外0.5cm、1.0cm、1.5cm处子宫肌瘤组织。以免疫组化法检测超声消融靶区边缘雌、孕激素受体及芳香化酶(P450酶)的表达,以Western-blot半定量检测P450酶蛋白表达水平。结果靶区周围肌瘤组织温度也有不同程度升高,并且靶区外位点的温度逐渐降低。与对照组比较,靶区外肌瘤组织雌、孕激素受体表达均无明显改变。免疫组化及Western-blot半定量结果显示P450酶蛋白在靶区外0.5cm、1.0cm的表达明显低于对照组(P<0.05)。结论超声消融部分子宫肌瘤后,在一定范围内的残余子宫肌瘤的生长会被抑制,其机制与温度影响P450酶的蛋白表达有关。

Objective To analyze the mechanism of outcome of residual uterine fibroid tissue after high intensity focused ultrasound （HIFU） ablation by detecting the expression of estrogen receptor （ER） and progesterone receptor （PR） as well as P450 aromatase on different sites of uterine fibroid tissue outside the ablated areas. Methods MR-guided HIFU ablation was performed on 8 uterine fibroid samples under the acoustic power of 400 W for 60 s. During ablation, temperature ele- vation was monitored by MR system. The experimental fibroid tissue was taken at 0.5 （A）, 1.0 （B）, 1.5 cm （C） outside necrotic tissue after ablation respectively, and the controls were selected from the uterine fibroids before ablation. Immuno- histochemistry was applied to detect the expression of ER, PR and P450 aromatase, and Western-blot was applied for semi- quantitative detection of P450 aromatase protein. Results Different degrees of temperature elevation outside ablated area were shown on temperature maps. The expression of ER and PR at point A, B and C were similar to the control group. The level of P450 aromatase protein at point A, B was significantly lower than that of control group （P〈0. 05） proved by immunohistochemieal detection and Western-blot. Conclusion The mechanism on inhibition of residual uterine fibroids within certain range after ultrasound ablation may be related to the expression of P450 aromatase protein affected by tem- perature.