摘要
Autocrine secretion is a concept which emerges in the search for the molecular basis of malignant tumour. Tumour cells can produce endogenous polypeptide growth factors which act on their producer cells via functional external receptors. This process has been termed 'autocrine secretion'. Autocrine hypothesis explains the malignant growth of tumour cells satisfactorily. Transforming growth factor-α (TGF-α)is one of the typical autocrine growth factors. TGF-α can induce the reversible phenotypic transformation of normal rat kidney cells in the presence of other growth factors. This suggests that TGF-α may play an im-
