B64
Expression of DPPA3 (STELLA), EDR1 (PHC1), GDF3, and NANOG, putative stem cell genes on chromosome 12, in breast carcinoma: a preliminary study
Chetana Ruangpratheep, Linda Potter, Jacqueline Shaw, Rosemary Walker
University of Leicester, UK
Background
In breast cancer, changes to chromosome 12 correlate with poor clinical outcome. According to the concept of breast stem cells and carcinogenesis, stem cell associated genes on this chromosome could be reactivated in the development of breast cancer. These genes may also play a role in tumour progression. This study investigated putative stem cell genes on chromosome 12 in the breast.
Method
mRNA expression of DPPA3 (STELLA), EDR1 (PHC1), GDF3, and NANOG genes was evaluated in 8 normal breast tissues from reduction mammoplasty, 7 breast cancer cell lines (HBL-100, MCF7, MDA-MB-231, MDA-MB-436, MDA-MB-468, T47D, and ZR-75-1), and 20 breast carcinoma tissues [3 ductal carcinoma in situ (DCIS), 13 invasive (infiltrating) ductal carcinoma not otherwise specified (IDC-NOS), and 4 combined DCIS with IDC-NOS] by using TaqMan quantitative reverse transcriptase polymerase chain reaction (QRT-PCR).
Results
DPPA3 (STELLA) was expressed at higher levels in MCF7, MDA-MB-436, MDA-MB-468, and ZR-75-1 cells than in normal breast tissue, whereas EDR1 (PHC1) and NANOG were expressed at higher levels in ZR-75-1 cells compared to normal breast. In the carcinomas, DPPA3 (STELLA) mRNA was up-regulated compared to normal breast in 2 (10%) IDC-NOS cases; NANOG was only detected in 4 of 8 normal breast samples, but was expressed in all tumour tissues; and EDR1 (PHC1) was expressed at low levels in all samples. GDF3 mRNA was not detected in cell lines or tissues after 50 cycles of PCR.
Conclusion
This preliminary study shows that up-regulation of putative stem cell genes on chromosome 12 may be associated with breast carcinogenesis. Only over-expression of DPPA3 (STELLA) has been found in IDC-NOS cases and in several breast cancer cell lines and merits further investigation for its role in development and progression of breast carcinomas.
