Luppi M, Morselli M, Bandieri E, Federico M, Marasca R, Barozzi P, Ferrari M G, Savarino M, Frassoldati A, Torelli G
Department of Medical Sciences, University of Modena, Italy.
Ann Oncol. 1996 Aug;7(6):619-24. doi: 10.1093/oxfordjournals.annonc.a010680.
Maspin, a recently identified protein related to the family of serpins, is believed to play a role in human breast cancer. In an effort to improve the present methods of detection, we have developed a reverse-transcriptase polymerase chain reaction (RT-PCR) assay for maspin transcript to identify small numbers of mammary carcinoma cells in the peripheral blood and bone marrow of patients with breast cancer.
Five non-neoplastic mammary tissue samples, 13 breast cancer specimens as well as 17 peripheral blood and 4 bone marrow samples from normal subjects were screened for the presence of maspin mRNA by RT-PCR. The same assay was applied to peripheral blood or bone marrow samples obtained from 29 patients with stages I to IV breast cancer.
By RT-PCR it was possible to amplify maspin mRNA in all of the primary and metastatic breast cancer specimens, but in none of the normal hemopoietic samples from healthy donors. Thus, detection of maspin transcript in the peripheral blood or marrow of a patient known to have breast cancer is indicative of the presence of mammary carcinoma cells. In reconstitution experiments, maspin RT-PCR reliably detected 10 mammary carcinoma cells in 1 million normal peripheral-blood mononuclear cells (PBMCs). None of the 9 patients with stages I, II, or III breast cancer had maspin transcript in peripheral blood. Of note, 3 of 9 patients with stage IV breast cancer receiving systemic therapy at the time of sample collection, but only 1 of 11 patients with stage IV not receiving therapy, had detectable maspin transcript in peripheral blood. Moreover, 3 marrow specimens from stage IV patients tested positive by this assay.
This pilot study suggests that maspin RT-PCR assay is a sensitive, specific and sufficiently rapid method for detection of small numbers of circulating cells and marrow micrometastases in breast cancer patients. The possibility of applying this assay in the detection of tumor cell contamination of both marrow and stem-cell apheresis harvests of breast cancer patients merits further investigation.
Maspin是一种最近发现的与丝氨酸蛋白酶抑制剂家族相关的蛋白质，被认为在人类乳腺癌中发挥作用。为了改进目前的检测方法，我们开发了一种用于检测maspin转录本的逆转录聚合酶链反应（RT-PCR）检测方法，以识别乳腺癌患者外周血和骨髓中的少量乳腺癌细胞。
通过RT-PCR筛选5份非肿瘤性乳腺组织样本、13份乳腺癌标本以及17份来自正常受试者的外周血和4份骨髓样本中maspin mRNA的存在情况。将相同的检测方法应用于从29例I至IV期乳腺癌患者获得的外周血或骨髓样本。
通过RT-PCR能够在所有原发性和转移性乳腺癌标本中扩增出maspin mRNA，但在健康供体的正常造血样本中均未扩增出。因此，在已知患有乳腺癌的患者外周血或骨髓中检测到maspin转录本表明存在乳腺癌细胞。在重组实验中，maspin RT-PCR能够可靠地检测出100万个正常外周血单个核细胞（PBMCs）中的10个乳腺癌细胞。9例I、II或III期乳腺癌患者中，外周血均未检测到maspin转录本。值得注意的是，9例IV期乳腺癌患者中有3例在样本采集时接受全身治疗，而11例未接受治疗的IV期患者中只有1例外周血中可检测到maspin转录本。此外，3例IV期患者的骨髓标本经该检测呈阳性。
这项初步研究表明，maspin RT-PCR检测是一种灵敏、特异且足够快速的方法，用于检测乳腺癌患者中的少量循环细胞和骨髓微转移。将该检测方法应用于检测乳腺癌患者骨髓和干细胞采集物中的肿瘤细胞污染的可能性值得进一步研究。
