title: Early responses of SiHa human squamous carcinoma cells to hypoxic signals.
abstract: We compared the responses of c-Jun/AP-1 transcriptional complexes with those of NF-kappa B, an established hypoxia-inducible transcriptional complex, in hypoxic SiHa human squamous carcinoma cells. We observed that NF-kappa B was activated rapidly, while AP-1 activation was detectable only after prolonged hypoxia. However, in parallel with NF-kappa B activation, hypoxia induced a protein kinase activity that could phosphorylate the transactivation domain of the ATF-2 transcription factor in vitro. Taken together, these experiments indicate that NF-kappa B can rapidly transduce hypoxic signals through increased DNA-binding and transactivation activities, whereas specific AP-1 (ATF-2/c-Jun) complexes may be activated under the same hypoxic conditions by a stress-reponsive MAPK pathway.
authors.affiliation: DIONEX CHEM CORP,SUNNYVALE,CA 94088. STANFORD UNIV,SCH MED,STANFORD,CA 94305.
authors.forename: K
authors.initials: K
authors.lastname: Laderoute
authors.forename: J
authors.initials: J
authors.lastname: Calaoagan
authors.forename: H
authors.initials: H
authors.lastname: Mendonca
authors.forename: W
authors.initials: W
authors.lastname: Ausserer
authors.forename: E
authors.initials: E
authors.lastname: Chen
authors.forename: A
authors.initials: A
authors.lastname: Giaccia
authors.forename: R
authors.initials: R
authors.lastname: Sutherland