Our study emphasizes that small allosteric molecules may act differently toward chemokine variants and thus selectively modulate interactions of specific chemokine subsets with their cognate receptors. Copyright © 2019 American Chemical Society.Cannabinoid receptor 2 (CB2) is a promising therapeutic target for immunological modulation. There is, however, a deficit of knowledge regarding CB2 signaling and function in human primary immunocompetent cells. We applied an experimental paradigm which closely models the in situ state of human primary leukocytes (PBMC; peripheral blood mononuclear cells) to characterize activation of a number of signaling pathways in response to a CB2-selective ligand (HU308). We observed a "lag" phase of unchanged cAMP concentration prior to development of classically expected Gαi-mediated inhibition of cAMP synthesis. Application of G protein inhibitors revealed that this apparent lag was a result of counteraction of Gαi effects by concurrent Gαs activation. Monitoring downstream signaling events showed that activation of p38 was mediated by Gαi, whereas ERK1/2 and Akt phosphorylation were mediated by Gαi-coupled βγ. Activation of CREB integrated multiple components; Gαs and βγ mediated ∼85% of the response, while ∼15% was attributed to Gαi. Responses to HU308 had an important functional outcome-secretion of interleukins 6 (IL-6) and 10 (IL-10). IL-2, IL-4, IL-12, IL-13, IL-17A, MIP-1α, and TNF-α were unaffected. IL-6/IL-10 induction had a similar G protein coupling profile to CREB activation. All response potencies were consistent with that expected for HU308 acting via CB2. Additionally, signaling and functional effects were completely blocked by a CB2-selective inverse agonist, giving additional evidence for CB2 involvement. This work expands the current paradigm regarding cannabinoid immunomodulation and reinforces the potential utility of CB2 ligands as immunomodulatory therapeutics. Copyright © 2019 American Chemical Society.Sensitivity to microtubule-targeting agents (MTAs) varies among cancers and predicting the response of individual cancer patients to MTAs remains challenging. As microtubules possess vast molecular heterogeneity generated by tubulin isotypes and their post-translational modifications, we questioned whether this heterogeneity can impact MTA sensitivity. We investigated microtubule heterogeneity in 15 glioblastoma cell lines and measured sensitivity of orthogonal MTAs using a per-division growth rate inhibition method that corrects for the confounding effects of variable cell proliferation rates. We found that the tubulin profile is unique for each glioblastoma cell line and that the total α- and β-tubulin levels impact on MTA sensitivity. The baseline levels of α- and β-tubulin were up to 20% lower in cells that were not effectively killed by MTAs. We report that lower α/β-tubulin expression is associated with lack of cell differentiation and increased expression of stemness markers. selleckchem The dedifferentiated stem-like cells with low α/β-tubulin levels survive MTAs treatment via reversible nonmutational dormancy. Our findings provide novel insights into the relationships between microtubules and MTAs and lay a foundation for better understanding of the sensitivity of cancer cells to MTAs. Copyright © 2019 American Chemical Society.The integrin αVβ3 receptor has been implicated in several important diseases, but no antagonists are approved for human therapy. One possible limitation of current small-molecule antagonists is their ability to induce a major conformational change in the receptor that induces it to adopt a high-affinity ligand-binding state. In response, we used structural inferences from a pure peptide antagonist to design the small-molecule pure antagonists TDI-4161 and TDI-3761. Both compounds inhibit αVβ3-mediated cell adhesion to αVβ3 ligands, but do not induce the conformational change as judged by antibody binding, electron microscopy, X-ray crystallography, and receptor priming studies. Both compounds demonstrated the favorable property of inhibiting bone resorption in vitro, supporting potential value in treating osteoporosis. Neither, however, had the unfavorable property of the αVβ3 antagonist cilengitide of paradoxically enhancing aortic sprout angiogenesis at concentrations below its IC50, which correlates with cilengitide's enhancement of tumor growth in vivo. Copyright © 2019 American Chemical Society.Multiple sclerosis (MS) is an immune-mediated disease of the central nervous system characterized by a complex lesion microenvironment. Although much progress has been made in developing immunomodulatory treatments to reduce myelin damage and delay the progression of MS, there is a paucity in treatment options that address the multiple pathophysiological aspects of the disease. Currently available immune-centered therapies are able to reduce the immune-mediated damage exhibited in MS patients, however, they cannot rescue the eventual failure of remyelination or permanent neuronal damage that occurs as MS progresses. Recent advances have provided a better understanding of remyelination processes, specifically oligodendrocyte lineage cell progression following demyelination. Further there have been new findings highlighting various components of the lesion microenvironment that contribute to myelin repair and restored axonal health. In this review we discuss the complexities of myelin repair following immune-mediated damage in the CNS, the contribution of animal models of MS in providing insight on OL progression and myelin repair, and current and potential remyelination-centered therapeutic targets. As remyelination therapies continue to progress into clinical trials, we consider a dual approach targeting the inflammatory microenvironment and intrinsic remyelination mechanisms to be optimal in aiding MS patients. Copyright © 2019 American Chemical Society.Regulation of cellular death is central to nearly all physiological routines and is dysregulated in virtually all diseases. Cell death occurs by two major processes, necrosis which culminates in a pervasive inflammatory response and apoptosis which is largely immunologically inert. As necrosis has long been considered an accidental, unregulated form of cellular death that occurred in response to a harsh environmental stimulus, it was largely ignored as a clinical target. However, recent elegant studies suggest that certain forms of necrosis can be reprogrammed. However, scant little is known about the molecules and pathways that orchestrate calcium-overload-induced necrosis, a main mediator of ischemia/reperfusion (IR)-induced cardiomyocyte cell death. To rectify this critical gap in our knowledge, we performed a novel genome-wide siRNA screen to identify modulators of calcium-induced necrosis in human muscle cells. Our screen identified multiple molecular circuitries that either enhance or inhibit this process, including lysosomal calcium channel TPCN1, mitophagy mediatorTOMM7, Ran-binding protein RanBP9, Histone deacetylase HDAC2, chemokine CCL11, and the Arp2/3 complex regulator glia maturation factor-γ (GMFG).