DNA Damage Is a Prerequisite for p53-Mediated Proteasomal Degradation of HIF-1α in Hypoxic Cells and Downregulation of the Hypoxia Marker Carbonic Anhydrase IX

Kaluzová, Milota; Kaluz, Štefan; Lerman, Michael I.; Stanbridge, Eric J.

doi:10.1128/mcb.24.13.5757-5766.2004

Cited by 80 publications

(87 citation statements)

References 41 publications

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“…It has been shown that overexpression of p53 is able to inhibit HIF-dependent activation of transcription (49,50), and p53-deficient cells show higher levels of HIF transactivation activity and higher inducibility of HIF target genes (51,52). These studies are consistent with a model where HIF-1␣ and p53 compete for a common factor important for activation of transcription.…”

Section: Discussionsupporting

confidence: 78%

Complex Regulation of the Transactivation Function of Hypoxia-inducible Factor-1α by Direct Interaction with Two Distinct Domains of the CREB-binding Protein/p300

Ruas

Berchner‐Pfannschmidt

Malik

et al. 2010

Journal of Biological Chemistry

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Activation of transcription in response to low oxygen tension is mediated by the hypoxia-inducible factor-1 (HIF-1). HIF-1 is a heterodimer of two proteins: aryl hydrocarbon receptor nuclear translocator and the oxygen-regulated HIF-1␣. The C-terminal activation domain of HIF-1␣ has been shown to interact with cysteine/ histidine-rich region 1 (CH1) of the coactivator CBP/p300 in a hypoxia-dependent manner. However, HIF forms lacking C-terminal activation domain (naturally occurring or genetically engineered) are still able to activate transcription of target genes in hypoxia. Here, we demonstrate that the N-terminal activation domain (N-TAD) of HIF-1␣ interacts with endogenous CBP and that this interaction facilitates its transactivation function. Our results show that interaction of HIF-1␣ N-TAD with CBP/p300 is mediated by the CH3 region of CBP known to interact with, among other factors, p53. Using fluorescence resonance energy transfer experiments, we demonstrate that N-TAD interacts with CH3 in vivo. Coimmunoprecipitation assays using endogenous proteins showed that immunoprecipitation of CBP in hypoxia results in the recovery of a larger fraction of HIF-1␣ than of p53. Chromatin immunoprecipitation demonstrated that at 1% O 2 CBP is recruited to a HIF-1␣ but not to a p53 target gene. Upon activation of both pathways, lower levels of chromatin-associated CBP were detected at either target gene promoter. These results identify CBP as the coactivator directly interacting with HIF-1␣ N-TAD and mediating the transactivation function of this domain. Thus, we suggest that in hypoxia HIF-1␣ is a major CBP-interacting transcription factor that may compete with other CBP-dependent factors, including p53, for limiting amounts of this coactivator, underscoring the complexity in the regulation of gene expression by HIF-1␣.

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Section: Discussionsupporting

confidence: 78%

Complex Regulation of the Transactivation Function of Hypoxia-inducible Factor-1α by Direct Interaction with Two Distinct Domains of the CREB-binding Protein/p300

Ruas

Berchner‐Pfannschmidt

Malik

et al. 2010

Journal of Biological Chemistry

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“…Few have investigated on whether and how HIF-1 interacts with mutant p53. 16,20 We used two isogenic fibrosarcoma cells containing wild-type and mutant p53 in this study. HT1080-6TG cells were defective in two sites of the DNA binding site and lost transcription activities.…”

Section: Discussionmentioning

confidence: 99%

“…Most studies of cross talk between HIF-1 and p53 focused on the direct interaction between proteins, regulation of the cell cycle, apoptosis and the expression of downstream genes. 11,12,[15][16][17][18][19][20] p53 mutation was associated with a malignant phenotype, and HIF-1 could enhance such effects. At least part of the proapoptotic action of HIF-1 was realized by inhibition of p53 degradation.…”

Section: Introductionmentioning

confidence: 99%

Effects of lentivirus-mediated HIF-1α knockdown on hypoxia-related cisplatin resistance and their dependence on p53 status in fibrosarcoma cells

Hao

Song

et al. 2008

Cancer Gene Ther

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Therapy targeting hypoxia-inducible factor-1 (HIF-1) to reverse the hypoxia-related drug resistance has received much interest. Despite a close interaction between HIF-1 and p53 and that p53 mutation is seen in 450% of tumors, whether HIF-1 silencing by targeted therapy depends on tumor p53 status remains unknown. Two isogenic fibrosarcoma cells HT1080 (wild-type p53) and HT1080-6TG (mutant p53) were transduced with HIF-1a-specific RNAi lentiviral vectors and selected with blasticidin. Real-time PCR and western blot analysis of HIF-1a mRNA and protein respectively validated the silencing effects. Cells were first preconditioned under hypoxia (0.5% O 2 ) for 4 h and then co-treated with cisplatin for another 24 h. MTT was used for assessment of chemosensitivity to cisplatin. Moreover, annexin V and propidium iodide staining was detected on flow cytometry for analysis of cisplatin-induced apoptosis. Furthermore, changes of some Bcl-2 family members were detected on western blotting. Exposure to hypoxia significantly increased resistance to cisplatin than exposure to normoxia. HIF-1a knockdown could reverse hypoxia-related resistance to cisplatin and apoptotic resistance only in HT1080 cells, but had little effect on HT1080-6TG cells. With HIF-1a knockdown, Bid expression was higher in HT1080 than in HT1080-6TG under hypoxia. In summary, HIF-1 targeted therapy to reverse hypoxia-related cisplatin resistance depends on normal p53 status. Changes of Bid expression levels under hypoxia might contribute in part to the differential response to HIF-1a silencing in cells with different p53 status.

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“…However, the combination of RITA and Nutlin-3, as well as Topotecan alone or in combination with Nutlin-3, indeed decreased HIF-1a protein levels. These findings would fit into a model in which a certain level of DNA damage response is required for p53-mediated downregulation of HIF-1a (Kaluzova et al, 2004). Interestingly, HIF-2a seemed to partially compensate for loss of HIF-1a.…”

Section: Discussionmentioning

confidence: 99%

Synergistic growth inhibition based on small-molecule p53 activation as treatment for intraocular melanoma

Lange

Lodder

et al. 2011

Oncogene

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The prognosis of patients with uveal melanoma is poor. Because of the limited efficacy of current treatments, new therapeutic strategies need to be developed. Because p53 mutations are uncommon in uveal melanoma, reactivation of p53 may be used to achieve tumor regression. We investigated the use of combination therapies for intraocular melanoma, based on the p53 activators Nutlin-3 and reactivation of p53 and induction of tumor cell apoptosis (RITA) and the topoisomerase I inhibitor Topotecan. Nutlin-3 treatment induced p53-dependent growth inhibition in human uveal melanoma cell lines. The sensitivity to Nutlin-3 of the investigated cell lines did not correlate with basal Hdm2 or Hdmx levels. Nutlin-3 synergized with RITA and Topotecan to induce apoptosis in uveal melanoma cell lines and short-term cultures. Drug synergy correlated with enhanced induction of p53-Ser46 phosphorylation, which was attenuated by ATM inhibition. Nutlin-3 and Topotecan also significantly delayed tumor growth in vivo in a murine B16F10 model for ocular melanoma. Combination treatment appeared to inhibit tumor growth slightly more efficient than either drug alone. Nutlin-3, RITA and Topotecan lead to comparable p53 activation and growth inhibition under normoxia and hypoxia. Treatment with Nutlin-3 or RITA had no effect on HIF-1a induction by hypoxia, whereas the combination of these two drugs did inhibit hypoxia-induced HIF-1a. Also Topotecan, alone or in combination with Nutlin-3, reduced HIF-1a protein levels, suggesting that a certain level of DNA damage response is required for p53-mediated downregulation of HIF-1a. In conclusion, combination treatments based on small-molecule-induced p53 activation may have clinical potential for uveal melanoma.

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DNA Damage Is a Prerequisite for p53-Mediated Proteasomal Degradation of HIF-1α in Hypoxic Cells and Downregulation of the Hypoxia Marker Carbonic Anhydrase IX

Cited by 80 publications

References 41 publications

Complex Regulation of the Transactivation Function of Hypoxia-inducible Factor-1α by Direct Interaction with Two Distinct Domains of the CREB-binding Protein/p300

Complex Regulation of the Transactivation Function of Hypoxia-inducible Factor-1α by Direct Interaction with Two Distinct Domains of the CREB-binding Protein/p300

Effects of lentivirus-mediated HIF-1α knockdown on hypoxia-related cisplatin resistance and their dependence on p53 status in fibrosarcoma cells

Synergistic growth inhibition based on small-molecule p53 activation as treatment for intraocular melanoma

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