A novel member of the heregulin superfamily has been identified which is designated
"-HRG". This molecule, secreted by human breast cancer MDA-MB-175 cells,
leads to the formation of a constitutive active receptor complex and stimulates
the growth of these cells in an autocrine manner. -HRG polypeptide and nucleic
acid are disclosed, together with various uses therefor (e.g. use of -HRG
nucleic acid for the recombinant production of -HRG). -HRG antagonists
(e.g. neutralizing antibodies and antisense nucleic acid molecules) as well as
uses therefor are also described.
