In this phase 2 trial, nemolizumab at all monthly doses significantly improved pruritus in patients with moderate-to-severe atopic dermatitis, which showed the efficacy of targeting interleukin-31 receptor A. The limited size and length of the trial preclude conclusions regarding adverse events. (Funded by Chugai Pharmaceutical; XCIMA ClinicalTrials.gov number, NCT01986933 .).
The highly invasive behavior of glioblastoma cells contributes to the morbidity and mortality associated with these tumors. The integrin-mediated adhesion and migration of glioblastoma cells on brain matrix proteins is enhanced by stimulation with growth factors, including platelet-derived growth factor (PDGF). As focal adhesion kinase (FAK), a nonreceptor cytoplasmic tyrosine kinase, has been shown to promote cell migration in various other cell types, we analysed its role in glioblastoma cell migration. Forced overexpression of FAK in serumstarved glioblastoma cells plated on recombinant (rec)-osteopontin resulted in a twofold enhancement of basal migration and a ninefold enhancement of PDGF-BBstimulated migration. Both expression of mutant FAK(397F) and the downregulation of FAK with small interfering (si) RNA inhibited basal and PDGF-stimulated migration. FAK overexpression and PDGF stimulation was found to increase the phosphorylation of the Crk-associated substrate (CAS) family member human enhancer of filamentation 1 (HEF1), but not p130CAS or Src-interacting protein (Sin)/Efs, although the levels of expression of these proteins was similar. Moreover downregulation of HEF1 with siRNA, but not p130CAS, inhibited basal and PDGF-stimulated migration. The phosphorylated HEF1 colocalized with vinculin and was associated almost exclusively with 0.1% Triton X-100 insoluble material, consistent with its signaling at focal adhesions. FAK overexpression promoted invasion through normal brain homogenate and siHEF1 inhibited this invasion. Results presented here suggest that HEF1 acts as a necessary and specific downstream effector of FAK in the invasive behavior of glioblastoma cells and may be an effective target for treatment of these tumors.
We have reported previously that the expression of focal adhesion kinase (FAK) is elevated in glioblastomas and that expression of FAK promotes the proliferation of glioblastoma cells propagated in either soft agar or in the C.B.17 severe combined immunodeficiency (scid) mouse brain. We therefore determined the effect of FAK on cell cycle progression in these cells. We found that overexpression of wild-type FAK promoted exit from G 1 in monolayer cultures of glioblastoma cells, enhanced the expression of cyclins D1 and E while reducing the expression of p27 Kip1 and p21 Waf1 , and enhanced the kinase activity of the cyclin D1-cyclin-dependent kinase-4 (cdk4) complex. Transfection of the monolayers with a FAK molecule in which the autophosphorylation site is mutated (FAK397F) inhibited exit from G 1 and reduced the expression of cyclins D1 and E while enhancing the expression of p27 Kip1 and p21 Waf1 . Small interfering RNA (siRNA)-mediated down-regulation of cyclin D1 inhibited the enhancement of cell cycle progression observed on expression of wild-type FAK, whereas siRNA-mediated down-regulation of cyclin E had no effect. siRNAmediated down-regulation of p27Kip1 overcame the inhibition of cell cycle progression observed on expression of FAK397F, whereas down-regulation of p21Waf1 had no effect. These results were confirmed in vivo in the scid mouse brain xenograft model in which propagation of glioblastoma cells expressing FAK397F resulted in a 50% inhibition of tumor growth and inhibited exit from G 1 . Taken together, our results indicate that FAK promotes proliferation of glioblastoma cells by enhancing exit from G 1 through a mechanism that involves cyclin D1 and p27 Kip1 .FAK 1 is a nonreceptor cytoplasmic tyrosine kinase. It has been shown to be activated on clustering of integrin receptors in the cell membrane or by the ligation of multiple growth factor receptors (1-3). Activation occurs through phosphorylation of Tyr 397 , either through autophosphorylation or Src-induced phosphorylation (4). Clustering of integrin receptors occurs during cell attachment, and the receptors localize to focal contacts (early adhesion complexes) where, in a temporally related manner, a signaling complex is assembled which includes FAK as well as cellular Src and other kinases, cytoskeletal proteins, and adaptor molecules (3, 5, 6). In nonmalignant and nontransformed cells, this localization of FAK to focal contacts or focal adhesions (mature adhesion complexes) has been shown to be necessary for its activation, indicating that FAK activation is regulated by integrin receptor engagement or cell adhesion in these cells. In contrast, in malignant or transformed cells, the activation of FAK does not appear to be regulated solely by cell adhesion or integrin receptor engagement. For example, we have shown the activation of FAK (phosphorylation of Tyr 397 ) in glioblastoma cells propagated in suspension, suggesting that the mechanisms governing the activation of FAK in malignant or transformed cells may differ from those util...
Enhanced expression of both integrin ␣ v  3 and platelet-derived growth factor receptor (PDGFr) has been described in glioblastoma tumors. We therefore explored the possibility that integrin ␣ v  3 cooperates with PDGFr to promote cell migration in glioblastoma cells, and extended the study to identify the Src family members that are activated on PDGF stimulation. Glioblastoma cells utilize integrins
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