Hypoxia-inducible factor-1 (HIF-1), as a transcription factor, plays an important role in the adaptation to hypoxic microenvironment within tumors. It can induce a series of genes transcription that participate in angiogenesis, glucose metabolism, cell proliferation, and cell migration/invasion. Thus HIF-1 not only allows cancer cells to survive in hypoxic microenvironment, but also makes the tumor more aggressive. Moreover, HIF-1 also induces tumors to acquire resistance to chemo-/radio-therapy, and is related to poor prognosis. HIF-1 emerges gradually as a potential target to develop new antitumor drugs. This paper reviews recent progress in this field.
Amphotericin B ; pharmacology ; Animals ; Antineoplastic Agents ; pharmacology ; Echinomycin ; pharmacology ; Humans ; Hypoxia-Inducible Factor 1 ; antagonists & inhibitors ; genetics ; metabolism ; Indazoles ; pharmacology ; Sirolimus ; analogs & derivatives ; pharmacology ; Topotecan ; pharmacology ; Transcription, Genetic

Echinomycin is a small-molecule inhibitor of hypoxia-inducible factor-1 DNA-binding activity, which plays a crucial role in ovarian ovulation in mammalians. The present study was designed to test the hypothesis that hypoxia-inducible factor (HIF)-1alpha-mediated endothelin (ET)-2 expressions contributed to ovarian ovulation in response to human chorionic gonadotropin (hCG) during gonadotropin-induced superuvulation. By real-time RT-PCR analysis, ET-2 mRNA level was found to significantly decrease in the ovaries after echinomycin treatment, while HIF-1alpha mRNA and protein expression was not obviously changed. Further analysis also showed that these changes of ET-2 mRNA were consistent with HIF-1 activity in the ovaires, which is similar with HIF-1alpha and ET-2 expression in the granulosa cells with gonadotropin and echinomycin treatments. The results of HIF-1alpha and ET-2 expression in the granulosa cells transfected with cis-element oligodeoxynucleotide (dsODN) under gonadotropin treatment further indicated HIF-1alpha directly mediated the transcriptional activation of ET-2 during gonadotropin-induced superuvulation. Taken together, these results demonstrated that HIF-1alpha-mediated ET-2 transcriptional activation is one of the important mechanisms regulating gonadotropin-induced mammalian ovulatory precess in vivo.
Animals ; Cells, Cultured ; Chorionic Gonadotropin/*pharmacology ; Echinomycin/*pharmacology ; Endothelin-2/genetics/*metabolism ; Female ; Gonadotropins, Equine/*pharmacology ; Granulosa Cells/drug effects/metabolism ; Humans ; Hypoxia-Inducible Factor 1, alpha Subunit/*antagonists & inhibitors/genetics/metabolism/physiology ; Oligonucleotides/genetics ; Ovary/cytology/drug effects/physiology ; Rats ; Rats, Sprague-Dawley ; Superovulation/*drug effects ; Transcriptional Activation