Novartis

About: Novartis is a company organization based out in Basel, Switzerland. It is known for research contribution in the topics: Alkyl & Population. The organization has 41930 authors who have published 50566 publications receiving 1978996 citations. The organization is also known as: Novartis International AG.

The dTAG system for immediate and target-specific protein degradation

Abstract: Dissection of complex biological systems requires target-specific control of the function or abundance of proteins. Genetic perturbations are limited by off-target effects, multicomponent complexity, and irreversibility. Most limiting is the requisite delay between modulation to experimental measurement. To enable the immediate and selective control of single protein abundance, we created a chemical biology system that leverages the potency of cell-permeable heterobifunctional degraders. The dTAG system pairs a novel degrader of FKBP12F36V with expression of FKBP12F36V in-frame with a protein of interest. By transgene expression or CRISPR-mediated locus-specific knock-in, we exemplify a generalizable strategy to study the immediate consequence of protein loss. Using dTAG, we observe an unexpected superior antiproliferative effect of pan-BET bromodomain degradation over selective BRD4 degradation, characterize immediate effects of KRASG12V loss on proteomic signaling, and demonstrate rapid degradation in vivo. This technology platform will confer kinetic resolution to biological investigation and provide target validation in the context of drug discovery.

Differentiation of mouse embryonic stem cells into a defined neuronal lineage

Abstract: Although it has long been known that cultured embryonic stem cells can generate neurons, the lineage relationships with their immediate precursors remain unclear. We report here that selection of highly proliferative stem cells followed by treatment with retinoic acid generated essentially pure precursors that markers identified as Pax-6-positive radial glial cells. As they do in vivo, these cells went on to generate neurons with remarkably uniform biochemical and electrophysiological characteristics.

Interferon alpha increases the frequency of interferon gamma-producing human CD4+ T cells.

Abstract: An increased ratio of T helper type 2 (Th2)- vs Th1-like cells contributes to the immune dysregulation in allergic disease situations and in many chronic infections, including AIDS. Th2-type immune responses are characterized by Th cells that produce increased levels of interleukin-4 (IL-4) and decreased levels of interferon gamma (IFN-gamma). The induction of either a Th1- or a Th2-like phenotype may be critically controlled by the antigen-presenting cells and their cytokines, e.g., IFN-alpha. In this study we have determined the frequencies of potential IL-4- and/or IFN-gamma-producing T cells in the peripheral blood of randomly selected healthy individuals, and analyzed whether IFN-alpha controls IL-4 and/or IFN-gamma production. Purified CD4+ or CD8+ T cells were stimulated for 24 h via the T cell receptor/CD3 complex in the presence or absence of IFN-alpha, and single IL-4- and IFN-gamma-secreting cells were detected in enzyme-linked immunospot assays. In the absence of IFN-alpha, CD4 cells produced IFN-gamma at frequencies of 1:50-300, and produced IL-4 at frequencies of 1:110-<1:100,000. Addition of IFN-alpha during the activation of CD4 cells increased the levels of IFN-gamma mRNA. As a consequence, the numbers of IFN-gamma-producing CD4 cells and the amounts of secreted IFN-gamma increased 10-fold. In contrast, IFN-alpha did not increase the frequency of IL-4-secreting CD4 cells. In the absence of IFN-alpha, addition of exogenous IL-4 to cultures of CD4 cells suppressed IFN-gamma secretion by 70%. However, in the presence of IFN-alpha, IL-4 did not display any suppressive effect. Compared with CD4 cells, CD8 cells produced IFN-gamma more frequently (1:5-10) but IL-4 less frequently (1:5,300 to < 1:100,000). IFN-alpha did not display any effect on the frequency of either IFN-gamma or IL-4 production by CD8 cells. Taken together the results indicate that IFN-alpha increases the frequency of IFN-gamma-secreting CD4 Th cells and antagonizes the suppressive effect of IL-4 on IFN-gamma production. As a consequence, IFN-alpha may favor the induction and maintenance of Th1-like cells and thereby counteract Th2-driven allergic immune responses.

An F876L Mutation in Androgen Receptor Confers Genetic and Phenotypic Resistance to MDV3100 (Enzalutamide)

Abstract: Castration-resistant prostate cancer (CRPC) is the most aggressive, incurable form of prostate cancer. MDV3100 (enzalutamide), an antagonist of the androgen receptor (AR), was approved for clinical use in men with metastatic CRPC. Although this compound showed clinical efficacy, many initial responders later developed resistance. To uncover relevant resistant mechanisms, we developed a model of spontaneous resistance to MDV3100 in LNCaP prostate cancer cells. Detailed characterization revealed that emergence of an F876L mutation in AR correlated with blunted AR response to MDV3100 and sustained proliferation during treatment. Functional studies confirmed that ARF876L confers an antagonist-to-agonist switch that drives phenotypic resistance. Finally, treatment with distinct antiandrogens or cyclin-dependent kinase (CDK)4/6 inhibitors effectively antagonized ARF876L function. Together, these findings suggest that emergence of F876L may (i) serve as a novel biomarker for prediction of drug sensitivity, (ii) predict a “withdrawal” response to MDV3100, and (iii) be suitably targeted with other antiandrogens or CDK4/6 inhibitors. Significance: We uncovered an F876L agonist-switch mutation in AR that confers genetic and phenotypic resistance to the antiandrogen drug MDV3100. On the basis of this finding, we propose new therapeutic strategies to treat patients with prostate cancer presenting with this AR mutation. Cancer Discov; 3(9); 1030–43. ©2013 AACR . See related commentary by Nelson and Yegnasubramanian, [p. 971][1] This article is highlighted in the In This Issue feature, [p. 953][2] [1]: /lookup/volpage/3/971?iss=9 [2]: /lookup/volpage/3/953?iss=9