Zhao J, Xiang Y, Wan X R, Feng F Z, Cui Q C, Yang X Y
Department of Obstetrics and Gynecology, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Science, Beijing 100730, PR China.
Placenta. 2009 Sep;30(9):816-20. doi: 10.1016/j.placenta.2009.06.011. Epub 2009 Jul 31.
Choriocarcinoma is a highly malignant trophoblastic neoplasm. Most of them are gestational in origin, while non-gestational ones are exceedingly rare. The genetic origin, immunogenicity, sensitivity to chemotherapy and prognosis of these two kinds of conditions are quite different, so identification of these two kinds of choriocarcinoma is of great importance. The objective of this study is to distinguish choriocarcinoma as gestational or non-gestational and identify the causative pregnancy of gestational choriocarcinoma through molecular genetic analysis.
Twelve patients with choriocarcinoma, who had experienced surgery prior to chemotherapy, were enrolled in this study. DNA was prepared from blood samples from the patient and her partner using standard techniques. In order to prepare DNA from choriocarcinoma tissue, areas of choriocarcinoma were firstly microdissected from haematoxylin and eosin-stained sections. PCR amplification and fluorescent microsatellite genotyping were performed using DNA from the couples and captured tissue. The genetic contributions to the choriocarcinoma were determined by comparing the genotypes of the choriocarcinoma and that of the couples.
Four of twelve cases had only a maternal contribution, indicating a non-gestational origin. The remaining eight cases were all gestational in origin and the causative pregnancies were identified as AnCHM (androgenetic complete hydatidiform mole) in six and normal pregnancies in two respectively.
Microsatellite polymorphism analysis is a molecular approach for distinguishing the non-gestational choriocarcinoma from the gestational one, and can also be used to identify the causative pregnancy of gestational choriocarcinoma. Antecedent pregnancy prior to choriocarcinoma is not always its causative pregnancy. Therefore, it is reasonable to identify the causative pregnancy by its genetic origin, instead of clinical impression.
绒毛膜癌是一种高度恶性的滋养层肿瘤。其中大多数起源于妊娠，而非妊娠性绒毛膜癌极为罕见。这两种情况的遗传起源、免疫原性、对化疗的敏感性及预后差异很大，因此区分这两种绒毛膜癌非常重要。本研究的目的是通过分子遗传学分析区分妊娠性与非妊娠性绒毛膜癌，并确定妊娠性绒毛膜癌的致病妊娠。
本研究纳入了12例在化疗前接受过手术的绒毛膜癌患者。使用标准技术从患者及其伴侣的血液样本中提取DNA。为了从绒毛膜癌组织中提取DNA，首先从苏木精和伊红染色切片中显微切割出绒毛膜癌区域。使用夫妻双方及捕获组织的DNA进行PCR扩增和荧光微卫星基因分型。通过比较绒毛膜癌与夫妻双方的基因型来确定对绒毛膜癌的遗传贡献。
12例病例中有4例仅来自母亲，表明为非妊娠起源。其余8例均为妊娠起源，其中6例致病妊娠被确定为完全性雄激素化葡萄胎（AnCHM），2例为正常妊娠。
微卫星多态性分析是一种区分非妊娠性绒毛膜癌与妊娠性绒毛膜癌的分子方法，也可用于确定妊娠性绒毛膜癌的致病妊娠。绒毛膜癌之前的妊娠并不总是其致病妊娠。因此，通过遗传起源而非临床印象来确定致病妊娠是合理的。
