CEP17异常对评判乳腺癌HER-2基因扩增状态的影响

Effects of CEP17 abnormal on HER-2 gene status evaluation in breast carcinoma

目的探讨使用乳腺癌双色荧光原位杂交技术(fluorescence in situ hybridization,FISH)检测CEP17(17p11.1-q11.1)探针拷贝数与HER-2基因扩增间的关系,分析CEP17异常对乳腺癌HER-2基因扩增状态评判的影响。方法收集742例乳腺癌HER-2基因扩增标本,采用双色FISH技术及免疫组化法检测并进行回顾性分析。结果 742例乳腺癌HER-2 FISH检测结果显示,11例(1.48%)HER-2探针信号数>6个,但由于CEP17探针信号数异常而被判定为基因扩增阴性。结论乳腺癌组织中真正17号染色体多倍体的比例极其稀少;FISH检测的CEP17信号数不等同于真正17号染色体的数目,临床有一定比例的HER-2 FISH结果阴性的患者错失最佳治疗机会。

Purpose To discuss the relationship between the copy number of CEP17 （ 17p1 1.1-q11. 1 ） probe and HER-2 gene ampli- fication in HER-2 gene amplification status detection using duo-color fluorescence in situ hybridization （FISH）, and to evaluate the effects of CEP17 region abnormal on HER-2 gene amplification interpreting in breast cancer tissues. Methods 742 cases of breast cancer were collected. HER-2 gene amplification and protein expression were detected using duo-color FISH and immunohistochemistry and were retrospectively analyzed. Results Of 742 cases of breast cancer with HER-2 FISH detecting results, there are 11 cases exhibit more than 6 copy number of HER-2 signal per cell, however, those 11 cases （ 1.48% ） were judged to be negative of HER-2 amplification due to their abnormal in CEP17 region amplification. Conclusion True polyploidy of CEP17 is a rare event in breast cancer tissue. The copy number of CEP17 is different from the real number of chromosomel7 in FISH detection. A certain part of patients with negative FISH results of HER-2 most likely missed the best treatment opportunity.