P11, a novel peptide ligand containing a PDZ-binding motif (Ser-Asp-Val) with high affinity to integrin ␣ v ␤ 3 was identified from a hexapeptide library (PS-SPCL) using a protein microarray chip-based screening system. Here, we investigated the inhibitory mechanism of P11 (HSD-VHK) on tumor-induced angiogenesis via a pharmacoproteomic approach. P11 was rapidly internalized by , human umbilical vein endothelial cells (HUVECs) via an integrin ␣ v ␤ 3 -mediated event. Caveolin and clathrin appeared to be involved in the P11 uptake process. The cell-penetrating P11 resulted in suppression of bFGF-induced HUVEC proliferation in a dose-dependent manner. Phosphorylation of extracellular-signal regulated kinase (ERK1/2) and mitogen-activated protein kinase kinase (MEK) in bFGFstimulated HUVECs was inhibited by cell-permeable P11. Proteomic analysis via antibody microarray showed upregulation of p53 in P11-treated HUVECs, resulting in induction of apoptosis via activation of caspases-3, -8, and -9. Several lines of experimental evidence strongly suggest that the molecular mechanism of P11, a novel antiangiogenic agent, inhibits bFGF-induced HUVEC proliferation via mitogen-activated protein kinase kinase and extracellular-signal regulated kinase inhibition as well as p53-mediated apoptosis related with activation of

No abstract

We investigated the anti-angiogenic effects of the water extract of HangAmDan (WEHAD), which is a crude extract of nine Korean medicinal substances of animal and plant origin. In human umbilical vein endothelial cells, WEHAD significantly inhibited bFGF-induced proliferation, adhesion, migration, and capillary tube formation. We used an antibody array to perform an analysis of signaling proteins, which showed up-regulated expression of various proteins including RAD51, RAD52, and p73, and down-regulated expression of pFAK. Blood vessel formation in a chick chorioallantoic membrane (CAM) treated with WEHAD was markedly reduced in length compared with a PBS-treated control group. These results suggest that inhibition of angiogenesis by WEHAD may be the mechanism of action for the anti-cancer effects of HAD.angiogenesis, HangAmDan, WEHAD, antibody array, HUVEC Citation:

The inhibitory effects of the water extract of HangAmDan-B (WEHAD-B), which is a crude extract of eight Korean medicinal animals and plants on bFGF-induced neovascularization were investigated. WEHAD-B significantly prevented bFGF-induced HUVE cell proliferation, adhesion, migration, and capillary-like tubular network formation. Half-maximal inhibition of proliferation on the endothelial cells by WEHAD-B was observed at a concentration of approximately 250 μg/mL. Our antibody microarray-based ProteoChip data showed that WEHAD-B increased the expression of STAT1 and Rb2, which are involved in cell growth, apoptosis, and controlling the cell cycle in bFGF-induced HUVECs. These results indicate that the inhibition of bFGF-induced angiogenesis by WEHAD-B may be due to upregulation of cell signaling proteins, STAT1 and Rb2. The blood vessel formation in a chick chorioallantoic membrane (CAM) treated with WEHAD-B was markedly reduced in length compared with a PBS-treated control group. Taken together, these data suggest that antibody-arrayed ProteoChip technology may be an useful tool for determining molecular mechanism of natural products in biological samples.

No abstract

No abstract

Integrins consist of transmembrane glycoproteins noncovalently associated to form alphabeta heterodimers. Various alpha/beta associations determine binding specieficities for cell surface molecules of the immunoglobulin superfamily as well as for extracellular matrix components. Through their cytoplasmic domains, integrins are responsible for the transmission of signals between the intracellular and the extracellular environment. We immobilized an integrin alpha5beta1 microarray on a ProteoChip to screen Korean medicinal plant extracts for binding activity. The microarray preserved the integrin alpha5beta1-fibronectin interaction, and was suppressed by the synthetic RGD peptide. We identified ten extracts with high integrin affinity using a high-throughput, competitive inhibition assay. We also demonstrate the biological function of these extracts in HUVECs.

Specific transcription factors regulate the totipotent and pluripotent capability of embryonic stem cells. Amongst these regulatory transcription factors in embryonic stem cells, Oct4 and Nanog are master factors that also have unique characteristic ability of cell-specific pluripotency and self-renewal. The expression of Nanog in fibroblasts confirms increased cell proliferation and transformation of foci-forming phenotype indicative of its oncogenic potential. The expression of Oct4, interestingly, leads to transformation of non-tumorgenic mouse into tumorigenic mouse. Our current investigation ascertains that the resultant increase in DNA synthesis and cell proliferation is the consequence of transforming the phenotype into foci formation. We used a manually curetted ProteoChip to carry out the signaling protein microarray analysis, which revealed up-regulated expression of various proteins including FAK1, MEK1 and Raf1. Some of the proteins explain the mechanism by which Oct4 and Nanog transform the phenotype. In NIH3T3 cells expressed with mouse Oct4 (mOct4), mouse Nanog (mNanog) separately as well as together, the specific knockdown of mFAK1 inhibited morphological transformation of the cells, and their invasion activity. The mFAK1 overexpression leads to morphological transformation as shown with mOct4 and mNanog. Additionally, we showed that the ERK1/2 pathway is involved in the up-regulation of c-myc and cyclin D1 expression mediated by mFAK1. Our results signify that the combinatorial signaling protein-array using biomolecular approach may possibly provide us with a new tool to understand cellular homeostasis.