高分化及去分化脂肪肉瘤MDM2的检测及其临床意义

·论 著·

高分化及去分化脂肪肉瘤MDM2的检测及其

临床意义

邹　珏,范钦和,蔡　勇,宋国新

(南京医科大学第一附属医院病理科,南京　210029)

[摘要]　目的　研究高分化及去分化脂肪肉瘤石蜡包埋组织中M DM2基因和蛋白表达的可行性及临床意义。方法　收集17例高分化及去分化脂肪肉瘤,对照组肿瘤标本18倒,均为甲醛固定石蜡包埋组织,M DM2基因检测用反转录聚合酶链反应(RT2PCR)法,以看家基因β2actin为内参照。蛋白检测用免疫组化EnVision二步法。结果　用RT2PCR法检测的10例高分化及去分化脂肪肉瘤均有M DM2基因表达,而对照组肿瘤标本只检测到β2actin基因,未检测到M DM2基因。17例高分化及去分化脂肪肉瘤M DM2蛋白表达率显著高于18例对照组肿瘤标本(P<0105)。

结论　在高分化和去分化脂肪肉瘤石蜡包埋组织中,RT2PCR法检测M DM2基因和免疫组化法检测M DM2蛋白可行,且两者结果对其诊断和鉴别诊断有意义。

[关键词]　脂肪肉瘤;　M DM2;　反转录聚合酶链反应;　免疫组化;　鉴别诊断

[中图分类号]　R73816　[文献标识码]　A　[文章编号]1007-8096(2007)03-0168-04

Detection of MDM2gene and protein in w ell2differentiated and dedifferentiated liposarcom a and its clinical significance

ZH OU Jue,FAN Qin2he,C AI Y onɡ,et al.

(Department of Pathology,the First A ffiliated H ospital,NɑnjinɡMedical University,Nɑnjinɡ210029,China)

Abstract:　Objective　T o assess the feasibility and significance of detecting M DM2gene and protein in paraffin2embedded tissues of well2differentiated liposarcoma(W D LPS)and dedifferentiated liposarcoma(DD LPS).　Methods　Seventeen formalin2 fixed and paraffin2embedded(FFPE)samples of W D LPSΠDD LPS were retrieved from archives and consultation materials,together with eighteen cases of controlled tum or.M DM2gene were detected by reverse transcription polymerase chain reaction(RT2PCR) and home2keeping geneβ2actin was used to detect the quality of mRNA.The proteins were detected by immunohischemistry of EnVision method.　R esults　T en W D LPSΠDD LPS samples were detected by RT2PCR and M DM2gene expression was detected in all the tum ors,as comparied withβ2actin mRNA.The positive rate of M DM2protein expressed in seventeen W D LPSΠDD LPS was significantly higher than that of eighteen controlled tum ors(P<0105).　Conclusions　RT2PCR for the detection of M DM2gene and immunohistochemistry for M DM2protein are feasible methods in FFPE tissues of W D LPSΠDD LPS.The results are meaning ful in diagnosis and differential diagnosis of the tum ors.

K ey w ords:Liposarcoma;M DM2;RT2PCR;Immunohistochemistry;Differential diagnosis

脂肪肉瘤根据其分子学特点可分为三大类:高分化脂肪肉瘤(well2differentiated liposarcoma, W D LPS)Π去分化脂肪肉瘤(dedifferentiated liposarcoma,DD LPS)、黏液Π圆细胞脂肪肉瘤和多形性脂肪肉瘤。在组织学上,W D LPS由较成熟的脂肪组织构成,但细胞常大小不一,伴散在的深染异型核及脂母细胞(图3);而DD LPS是一种含分化好的脂肪肉瘤样区及突然出现恶性的非脂肪源性的肉瘤样区两种成分的恶性脂肪源性肿瘤,肉瘤样区可向恶性纤维组织细胞瘤或纤维肉瘤样分化(图4)。大约有10%的W D LPS可能进展为DD LPS,有人认为W D LPS 进展为DD LPS是随着时间的延展而发展的,而且在细胞和分子遗传学特点上,W D LPS/DD LPS都有特征性环状和/或巨大标记染色体;研究显示,这些特征染色体由12q13215扩增而来,且这一区域最恒定的扩增是M DM2(human hom ologue of the murine double2 minute type2)基因[1-4]。镜下观察W D LPS与良性脂肪性肿瘤很相似,DD LPS去分化区域常常与恶性纤