A transgenic mouse model for the ductal carcinoma in situ (DCIS) of the mammary gland

The ductal carcinoma in situ (DCIS) of the mammary gland represents an earl y, pre-invasive stage in the development of invasive breast carcinoma and i s increasingly diagnosed since the introduction of high-quality mammography screening. Uncertainties in the prognosis for patients with DCIS have caus ed a controversial discussion about adequate treatment, and it is suspected that most patients undergoing mastectomy may be overtreated, In order to i mprove treatment and treatment decision, it therefore is highly desirable t o identify prognostic markers and therapeutic targets for DCIS. We here int roduce a set of transgenic mice (WAP-T and WAP-T-NP lines) presenting with various morphological forms of DCLS-like lesions. In these mite the SV40 la rge tumor antigen is specifically induced in epithelial cells of the termin al duct lobular units (TDLU), As a consequence of continuous expression of the oncogene, the animals develop multifocal DCIS and consequently invasive carcinoma within strain specific periods of latency. DCIS lesions in trans genic mire exhibit distinct architectural and cytological features which cl osely resemble those commonly present in humans, We therefore propose these transgenic lines as an experimental model to study the underlying molecula r events leading to DCIS and its progression to invasive disease.