Neural tube defects are among the most common of the malformations associated with diabetic embryopathy. To study the molecular mechanisms by which neural tube defects occur during diabetic pregnancy, we have developed a new experimental system using pregnant diabetic mice. In this system, the rate of neural tube defects is about three times higher in embryos of diabetic mice than in embryos of nondiabetic mice. Most of the defects affected presumptive midbrain and hindbrain structures and included open defects (i.e., exencephaly) and gross maldevelopment. By semiquantitative reverse transcription-polymerase chain reaction and in situ hybridization, we found that expression of Pax-3, a gene required for neural tube closure in the area of the midbrain and hindbrain, is significantly reduced in the embryos of diabetic mice. The same regions of the neural tube where Pax-3 had been underexpressed were found subsequently to contain high concentrations of cells undergoing apoptosis. Reduced expression of Pax-3 appears to be responsible for this apoptosis because apoptotic cells were also found at sites of neural tube defects in embryos carrying null mutation of the Pax-3 gene. Finally, mouse strains that carry null mutations in Pax-3 develop neural tube defects that resemble the malformations that occur in embryos of diabetic mice. These results suggest that Pax-3 is an important developmental control gene, expression of which is disturbed in embryos of diabetic mice, and that as a consequence, apoptosis of the neural tube occurs. This pathway may be responsible for many of the neural tube defects resulting from diabetic pregnancy.

Patient stratifi cation biomarkers that enable the translation of cancer genetic knowledge into clinical use are essential for the successful and rapid development of emerging targeted anticancer therapeutics. Here, we describe the identifi cation of patient stratifi cation biomarkers for NVP-BGJ398, a novel and selective fi broblast growth factor receptor (FGFR) inhibitor. By intersecting genome-wide gene expression and genomic alteration data with cell line-sensitivity data across an annotated collection of cancer cell lines called the Cancer Cell Line Encyclopedia, we show that genetic alterations for FGFR family members predict for sensitivity to NVP-BGJ398. For the fi rst time, we report oncogenic FGFR1 amplifi cation in osteosarcoma as a potential patient selection biomarker. Furthermore, we show that cancer cell lines harboring FGF19 copy number gain at the 11q13 amplicon are sensitive to NVP-BGJ398 only when concomitant expression of β-klotho occurs. Thus, our fi ndings provide the rationale for the clinical development of FGFR inhibitors in selected patients with cancer harboring tumors with the identifi ed predictors of sensitivity. SIGNIFICANCE:The success of a personalized medicine approach using targeted therapies ultimately depends on being able to identify the patients who will benefi t the most from any given drug. To this end, we have integrated the molecular profi les for more than 500 cancer cell lines with sensitivity data for the novel anticancer drug NVP-BGJ398 and showed that FGFR genetic alterations are the most significant predictors for sensitivity. This work has ultimately endorsed the incorporation of specifi c patient selection biomakers in the clinical trials for NVP-BGJ398. Cancer Discov; 2(12); 1118-33.

Activity of the sympathetic nervous system is an important factor involved in the pathogenesis of insulin resistance and associated metabolic and vascular abnormalities. In this study, we investigate the molecular basis of cross-talk between ␤ 3 -adrenergic and insulin signaling systems in mouse brown adipocytes immortalized by SV40 T infection. Insulin-induced tyrosine phosphorylation of the insulin receptor, insulin receptor substrate 1 (IRS-1), and IRS-2 was reduced by prestimulation of ␤ 3 -adrenergic receptors (CL316243). Similarly, insulin-induced IRS-1-associated and phosphotyrosineassociated phosphatidylinositol 3-kinase (PI 3-kinase) activity, but not IRS-2-associated PI 3-kinase activity, was reduced by ␤ 3 -adrenergic prestimulation. Furthermore, insulin-stimulated activation of Akt, but not mitogen-activated protein kinase, was diminished. Insulininduced glucose uptake was completely inhibited by ␤ 3 -adrenergic prestimulation. These effects appear to be protein kinase A-dependent. Furthermore inhibition of protein kinase C restored the ␤ 3 -receptor-mediated reductions in insulin-induced IRS-1 tyrosine phosphorylation and IRS-1-associated PI 3-kinase activity. Together, these findings indicate cross-talk between adrenergic and insulin signaling pathways. This interaction is protein kinase A-dependent and, at least in part, protein kinase C-dependent, and could play an important role in the pathogenesis of insulin resistance associated with sympathetic overactivity and regulation of brown fat metabolism.The sympathetic nervous system has long been recognized to play an important role in the pathogenesis of insulin resistance and associated metabolic and vascular abnormalities, such as type 2 diabetes, obesity, dyslipidemia, and hypertension (for a recent review see Ref. 1). At a molecular level, insulin has been shown to phosphorylate tyrosyl residues in the C terminus of the ␤ 2 -adrenergic receptor (2), whereas ␤-adrenergic stimulation can inhibit the activation of the insulin receptor in some tissues (3-7). However, the potential molecular mechanisms downstream of these interactions and their effects remain poorly elucidated.To investigate the cross-talk between the insulin and adrenergic signaling systems, we have utilized brown adipocytes. These provide an attractive cell model for several reasons. Brown adipose tissue (BAT) 1 is highly regulated by the sympathetic nervous system and expresses different subtypes of adrenergic receptors (8 -10), including the ␤ 3 -adrenergic receptor, a potential target for anti-obesity and anti-diabetic drug therapy (11,12). BAT is important in controlling energy balance in rodents by its capacity to uncouple mitochondrial respiration, a process mediated by the expression of the uncoupling protein-1 (UCP-1) (for recent review see Ref. 13 and references therein). And finally, BAT is an insulin-sensitive tissue and contains the main elements of the insulin signaling system (14 -17). Thus, in the cells binding of insulin to its receptor leads to activation of the r...