Development of mammary hyperplasia and neoplasia in MMTV-TGFα transgenic mice

Mammary gland specific hEGF receptor transgene expression induces neoplasia and inhibits differentiation

“…Additional secondary genetic events are likely to contribute to the tumor phenotype. In this respect, mammary gland speci®c TGFa overexpression leads to the development of mammary adenocarcinomas that also exhibit an increase in EGFR expression, supporting the hypothesis of an autocrine mechanism for transformation of the mammary epithelium by the EGFR (Matsui et al, 1990). Therefore an increase in the expression of the EGF-receptor and/or its ligands in mammary tissue might be a primary cause for tumor formation.…”

Signal transduction in mammary tumorigenesis: a transgenic perspective

“…Expression of TGFa in the mammary gland by virtue of the MMTV-LTR or metallothionein promoters causes epithelial hyperplasia and dysplasia and, in rare cases, results in tubular mammary tumors adenocarcinomas (Matsui et al, 1990;Sandgren et al, 1990). Additionally, multiparous animals expressing a member of the NRG family of ligands (NDFb2) develop palpable mammary tumors at long latencies and low penetrance (Krane and Leder, 1996).…”

Transforming growth factor alpha- and c-myc-induced mammary carcinogenesis in transgenic mice

“…TGFa is the most commonly identi®ed EGF-like growth factor in primary breast tumors as evidenced by the presence of TGFa mRNA and/or protein in 30 ± 70% of cases reported (reviewed in Rudland et al, 1995). In addition, overexpression of TGFa in the mammary gland of transgenic mice is potently oncogenic (Sandgren et al, 1990(Sandgren et al, , 1995Jhappan et al, 1990;Matsui et al, 1990;Halter et al, 1992;Smith et al, 1995), and coexpression of TGFa with other oncogenes shortens tumor latency (Sandgren et al, 1995;Amundadottir et al, 1995Amundadottir et al, , 1996Muller et al, 1996;Davies et al, 1999).…”