conditioned media collected under serum-free conditions over 24 to 48 h from 18 human colon adenocarcinoma cell lines were analyzed for transforming growth factor , types alpha and beta ( tgf-alpha and -beta ) , and platelet-derived growth factor in assays for anchorage-independent growth and radioreceptor competition .
C0040691
transforming growth
C0040688
tgf-alpha