Background: It is now well established that several environmental stress factors cause activation of p38 MAP kinase and JNK in various cell types to produce chemokines. Objective: To investigate the expression of CXC chemokines Gro/KC and SDF- 1a in rat's H4 hepatoma cells in response to heat shock, hyperosmolarity and oxidative stress. Methods: Hepatoma cells were maintained in MEM medium. Cel...

background: it is now well established that several environmental stress factors cause activation of p38 map kinase and jnk in various cell types to produce chemokines. objective: to investigate the expression of cxc chemokines gro/kc and sdf- 1a in rat's h4 hepatoma cells in response to heat shock, hyperosmolarity and oxidative stress. methods: hepatoma cells were maintained in mem medium...

The chemokine stromal-derived factor-1A (SDF-1A/CXCL-12) and its receptor, CXCR4, play a crucial role in adhesion and transendothelium migration (TEM) of prostate cancer cells. We tested the hypothesis that enhanced expression of CXCR4 in prostate cancer cells is dependent upon SDF-1A-mediated activation of nuclear factor-KB (NF-KB). SDF-1A increased the CXCR4 mRNA and protein expression in PC-...

The chemokine stromal-derived factor-1A (SDF-1A) regulates leukemic cell motility and proliferation; however, the importance of these functions in the growth and dissemination of leukemia is unclear. We examined SDF-1A–mediated responses of cells from 27 cases of acute lymphoblastic leukemia (ALL). Although cells from the majority of cases showed chemotactic and proliferative responses to SDF-1...

Platelet-derived growth factor B (PDGF-B) and its receptor, PDGFR-b, play a critical role in pericyte maturation; however, the mechanisms by which PDGF-B is upregulated in the tumor microenvironment remain unclear. We previously showed that upregulating stromal-derived factor, SDF-1a, in VEGF165-inhibited Ewing's sarcoma tumors (TC/siVEGF7-1) induced PDGF-BmRNA expression, increased infiltratio...

Emerging evidence shows that the stromal cell–derived factor 1 (SDF-1)/CXCR4 interaction regulates multiple cell signaling pathways and a variety of cellular functions such as cell migration, proliferation, and survival. There is little information linking the cellular functions and individual signaling pathways mediated by SDF-1 and CXCR4 in human cancer cells. In this study, we have shown tha...

The chemokine SDF-1a and its receptor CXCR4b guide germ cell migration in zebrafish by activating downstream signaling events. Boldajipour et al. (2008) now report that a second SDF-1a receptor, CXCR7, is also required for guided migration but does not function as a signaling receptor, and instead sequesters SDF-1a. These results highlight the importance of ligand clearance during guided cell m...

The genetic hallmark of hemangioblastomas and clear cellrenal cell carcinomas (CC-RCCs) is loss-of-function of the von Hippel-Lindau (VHL) tumor suppressor protein. VHL is required for oxygen-dependent degradation of hypoxiainducible factor-1A (HIF-1A). In hemangioblastomas and CC-RCCs, HIF-1A is constitutively overexpressed leading to increased transcription of HIF-1–regulated genes, including...

Primordial germ cell (PGC) migration in zebrafish is directed by the chemokine SDF-1a that activates its receptor CXCR4b. Little is known about the molecular mechanisms controlling the distribution of this chemoattractant in vivo. We demonstrate that the activity of a second SDF-1/CXCL12 receptor, CXCR7, is crucial for proper migration of PGCs toward their targets. We show that CXCR7 functions ...