Insulin-like growth factor (IGF)-binding protein-4 inhibits colony formation of colorectal cancer cells by IGF-independent mechanisms.
Effects of insulin-like growth factor-binding protein-4 (IGFBP-4) on proliferation, colony formation, and cell migration were assessed in IGF-sensitive and -insensitive colorectal cancer cell lines. In IGF-insensitive Isreco-1 cells, overexpression of IGFBP-4 reduced colony formation but not cell proliferation and migration, whereas exogenous IGF-II had no effect. In IGF-dependent LS1034 cells, IGFBP-4 inhibited all parameters of growth tested, whereas IGF-II partially restored reduced proliferation and cell migration only. In Isreco-2 cells, which lack endogenous IGF expression but are IGF sensitive, colony formation was also reduced by IGFBP-4. Therefore, specific parameters of malignant progression of colon carcinoma cells are distinctly affected by IGF-dependent and IGF-independent effects of IGFBP-4.
Institute of Molecular Animal Breeding and Biotechnology, Ludwig-Maximilian University of Munich, Munich, Germany.
Daniela
D
Diehl
Andreas
A
Hoeflich
Eckhard
E
Wolf
Harald
H
Lahm
D002455:Cell Division; D045744:Cell Line, Tumor; D015179:Colorectal Neoplasms / Q000473:pathology*; D006801:Humans; D018974:Insulin-Like Growth Factor Binding Protein 4 / Q000235:genetics / Q000502:physiology*; D009361:Neoplasm Invasiveness; D012333:RNA, Messenger / Q000032:analysis; D013002:Somatomedins / Q000502:physiology*
D018974:Insulin-Like Growth Factor Binding Protein 4; D012333:RNA, Messenger; D013002:Somatomedins