IGFBPs contribute to survival of pancreatic cancer cells under severely hypoxic conditions.
Protein synthesis in general is suppressed under hypoxic conditions in both cancer cells and normal cells. In human pancreatic cancer AsPC-1 cells, which are resistant to low oxygen tension, protein synthesis at day 4 under hypoxia (1% O(2)) was about 20% of that under normoxia. Secretion of some proteins actually increased in spite of a general reduction in protein synthesis; two of these proteins were insulin-like growth factor binding protein-1 (IGFBP-1) and IGFBP-3. Hypoxia also induced transcription of multiple IGFBPs. The IGFBPs contributed to reduced IGF signaling and to the survival of cancer cells under conditions of low oxygen tension.
Koga
Takumi
T
Osaka Medical Center for Cancer and Cardiovascular Diseases, Osaka 537-8511, Japan.
Endo
Hiroko
H
Miyamoto
Yasuhiro
Y
Mukai
Mutsuko
M
Akira
Shizuo
S
Inoue
Masahiro
M
D015687:Cell Hypoxia; D045744:Cell Line, Tumor; D002470:Cell Survival; D017077:Culture Media, Conditioned; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins / Q000378:metabolism*; D010190:Pancreatic Neoplasms / Q000378:metabolism*; D014176:Protein Biosynthesis
D017077:Culture Media, Conditioned; D018969:Insulin-Like Growth Factor Binding Proteins