Fasudil-induced hypoxia-inducible factor-1α degradation disrupts a hypoxia-driven vascular endothelial growth factor autocrine mechanism in endothelial cells

Abstract

Hypoxic response of endothelial cells (EC) is an important component of tumor angiogenesis. Especially, hypoxiainducible factor-1 (HIF-1) -dependent EC-specific mechanism is an essential component of tumor angiogenesis. Recently, the Rho/Rho-associated kinase (ROCK) signaling has been shown to play a key role in HIF-1A induction in renal cell carcinoma and trophoblast. The present study was designed to investigate whether low oxygen conditions might modulate HIF-1A expression through the Rho/ROCK signaling in human umbilical vascular ECs (HUVEC). Pull-down assay showed that hypoxia stimulated RhoA activity. Under hypoxic conditions, HUVECs transfected with small interfering RNA of RhoA and ROCK2 exhibited decreased levels of HIF-1A protein compared with nontargeted small interfering RNA transfectants, whereas HIF-1A mRNA levels were not altered. One of ROCK inhibitors, fasudil, inhibited hypoxia-induced HIF-1A expression without altering HIF-1A mRNA expression.

Effects of Inflammatory Factors on Mesenchymal Stem Cells and Their Role in the Promotion of Tumor Angiogenesis in Colon Cancer

“…In the tumor microenvironment, hypoxia can cause some effector cells to produce HIF-1␣, which is the upstream regulatory gene of VEGF (42). VEGF also has been demonstrated to interact with the HIF-1␣ via an autocrine loop (43,44). The level of VEGF and HIF-1␣ could directly and indirectly indicate the ability of a tumor to cause angiogenesis.…”

Ras homolog gene family, member A promotes p53 degradation and vascular endothelial growth factor‐dependent angiogenesis through an interaction with murine double minute 2 under hypoxic conditions

“…16 It is worth noting that previous reports indicated that RhoA is also a hypoxiatargeted gene that receives responses from HIF-1a/VEGF signaling under hypoxic conditions. 17,18 Combining these results, we hypothesized that RhoA may participate in the hypoxia-induced VEGF signaling through the MDM2-p53 pathway that regulates TNV angiogenesis in human malignancies.…”

“…17 Cell lysates were incubated with an anti-p53, anti-RhoA, or anti-MDM2 antibody. The immune complexes were precipitated with protein A-Sepharose or protein G-Sepharose 4B (Amersham Biosciences, Sunnyvale, Calf).…”

Fasudil inhibits lung carcinoma-conditioned endothelial cell viability and migration

“…Cell migration is a critical step in the process of angiogenesis (21). Therefore, we evaluated the effects of fasudil treatment on the migration of LCc-ECs using in vitro migration assays.…”