We have provided evidence that human breast cancer cells secrete a collection of separable growth factors (IGF-I, TGF α-like material, TGF β, a competency factor and an additional epithelial anchorage independent growth promoting activity). Some of these activities are estrogen inducible. Taken together, they are capable of promoting in vivo tumorigenesis of hormone dependent breast cancer cells in nude mice though not to the same extent as estrogen treatment of the mice. Hormone independent breast cancer cells, whether spontaneously arising in culture or constructed by DNA mediated gene transfer, appear to secrete such growth factors in increased amounts. Such an externalized system of autocrine and paracrine cell regulation obviously suggests multiple interventions which may eventually have clinical applicability in the control of neoplastic breast cancer growth.
|Original language||English (US)|
|Number of pages||8|
|State||Published - Dec 1 1985|
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