正常妊娠滋养层组织中Lin28B表达变化的研究

Expression and significance of Lin28B in trophoblast tissue of normal pregnancy

目的：探讨Lin28B在正常妊娠不同阶段滋养层细胞中的表达变化及其临床意义。方法：收集40例正常早期妊娠者（孕早期组），包括20例妊娠5～7＋6周（孕早A组）和20例妊娠耻12＋2周（孕早B组），15例孕17-27周（孕中期组），以及20例孕37～41周（孕晚期组），共75例正常孕妇的绒毛和胎盘组织。采用RT—qPCR、Westernblotting和免疫组织化学方法检测胎盘组织Lin28B基因和蛋白的表达差异及细胞定位。结果：①在正常妊娠不同时期的滋养层组织中细胞滋养细胞和合体滋养细胞中均可检测到Lin28B蛋白的表达。②Lin28BmRNA表达量各组间有统计学差异（P〈0．05），早孕A组最高，随着孕周进展逐渐下降，至孕晚期达最低水平。③正常妊娠不同时期的滋养层组织中Lin28B蛋白表达呈现为随着孕周的增加而逐渐下降趋势。结论：Lin28B在正常妊娠进展过程中表达下调，提示其可能参与了滋养细胞的增殖和浸润及胎盘的发育。

Objective： To investigate the expression and clinical significance of Lin28B in different stages of normal pregnancy trophoblast cells. Methods： Totally 75 cases of normal villi and placenta of pregnant women were collected, including 40 cases of early pregnancy （early pregnancy group） which consists of 20 cases of 5-7＋6-week gestation （early pregnancy group A） and 20 cases of 8-12＋2-week gestation （early pregnancy group B）, 15 cases of the second trimester pregnancy （middle pregnancy group） and 20 normal late pregnancy （late pregnancy group）. The expression and localization ofLin28B mRNA and protein in placenta were evaluated by RT-qPCR, Western blotting and immunohistochemistry. Results： 1） Lin28B was positively expressed in the villi and placeta of all groups. 2） Lin28B mRNA expression in each group was significantly different （P〈0.05）, the highest was in the early pregnancy group A and was decreased to the lowest level in the third trimester along with the progression of gestational age （P〈0.05）. 3） The expression of Lin28B in different stages of normal pregnancy trophoblast cells decreased gradually along with the progression of gestational age （P〈0.05）. Conclusion： The expressions of Lin28B in normal pregnancy progression presented down-regulated, suggesting that it might be involved in proliferation and infiltration functions oftrophoblast cells and the development of the placenta.