Detection of circulating tumor cells by reverse transcriptase polymerase chain reaction of maspin in patients with breast cancer undergoing conventional-dose chemotherapy.
OBJECTIVE
To establish, in patients with breast cancer subjected to primary conventional chemotherapy and enrolled in a prospective study, the mobilizing effect of therapy on potentially neoplastic cells by means of a reverse transcriptase polymerase chain reaction (RT-PCR) assay for mRNA of maspin, a protein related to the serpin family of protease inhibitors.


METHODS
Peripheral-blood samples were collected from 30 patients with histologically proven breast cancer before and 4 and 8 days after conventional chemotherapy for three consecutive courses. A total of 216 samples were screened for the presence of maspin mRNA by RT-PCR.


RESULTS
Before therapy, all samples but one were negative. After chemotherapy, 11 patients (38%) had positive samples. No difference in the rate of positivity was observed between groups defined according to initial stage, type of chemotherapy, Ki-67-related proliferative activity, or CA 15.3 expression.


CONCLUSIONS
Our results confirm that RT-PCR for maspin mRNA is a sensitive assay for the study of circulating potentially neoplastic mammary cells in patients with breast cancer. Moreover, our findings indicate a marked effect of conventional-dose chemotherapy on the mobilization of these cells in breast tumors. In our series of patients, this phenomenon does not seem to be associated with other known risk factors. Finally, the data suggest, without proving, an association between the presence of circulating maspin positive cells and a higher risk of disease progression. If this association could be confirmed, then the assay could have prognostic significance. However, larger confirmatory studies are necessary.
Sabbatini
R
R
Cattedra di Oncologia Medica ed Ematologia, Dipartimento di Oncologia ed Ematologia, Università di Modena, Modena, Italy.
Federico
M
M
Morselli
M
M
Depenni
R
R
Cagossi
K
K
Luppi
M
M
Torelli
G
G
Silingardi
V
V
D000328:Adult; D000368:Aged; D000970:Antineoplastic Agents / Q000032:analysis*; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000032:analysis; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000473:pathology*; D018450:Disease Progression; D005260:Female; D016147:Genes, Tumor Suppressor; D006801:Humans; D008875:Middle Aged; D009360:Neoplastic Cells, Circulating; D011446:Prospective Studies; D011506:Proteins / Q000032:analysis / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012307:Risk Factors; D015843:Serpins / Q000032:analysis / Q000235:genetics*
D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D011506:Proteins; D012333:RNA, Messenger; C085344:SERPIN-B5; D015843:Serpins