Survey of ex vivo drug combination effects in chronic lymphocytic leukemia reveals synergistic drug effects and genetic dependencies.

Drug combinations that target critical pathways are a mainstay of cancer care. To improve current approaches to combination treatment of chronic lymphocytic leukemia (CLL) and gain insights into the underlying biology, we studied the effect of 352 drug combination pairs in multiple concentrations by analysing ex vivo drug response of 52 primary CLL samples, which were characterized by "omics" profiling. Known synergistic interactions were confirmed for B-cell receptor (BCR) inhibitors with Bcl-2 inhibitors and with chemotherapeutic drugs, suggesting that this approach can identify clinically useful combinations. Moreover, we uncovered synergistic interactions between BCR inhibitors and afatinib, which we attribute to BCR activation by afatinib through BLK upstream of BTK and PI3K. Combinations of multiple inhibitors of BCR components (e.g., BTK, PI3K, SYK) had effects similar to the single agents. While PI3K and BTK inhibitors produced overall similar effects in combinations with other drugs, we uncovered a larger response heterogeneity of combinations including PI3K inhibitors, predominantly in CLL with mutated IGHV, which we attribute to the target's position within the BCR-signaling pathway. Taken together, our study shows that drug combination effects can be effectively queried in primary cancer cells, which could aid discovery, triage and clinical development of drug combinations.

Transcriptomic analysis of de novo folate biosynthetic genes in Lactobacillus plantarum strain 4_3 in fermented soybean.

Folate is an important intermediate in cellular metabolism. However, because of a lack of key enzymes in the folate biosynthetic pathway, humans require supplementation with dietary folate. Some Lactobacillus plantarum strains have the ability to produce folate. To gain a better understanding of the folate biosynthetic pathway in the L. plantarum strain 4_3, which generates high folate yields, L. plantarum strain 4_3 was grown in folic acid casei medium (FACM) and fermented soybean, after obtaining a draft genome sequence. The pH values and folate yields were monitored during culturing, as were the transcriptomic profiles of cultured bacteria. The folate content increased for 12 h and then decreased before increasing again. All the genes involved in the de novo biosynthesis of folate were detected in both the genomic and transcriptomic data. The upregulation of the para-aminobenzoate biosynthesis pathway could explain the folate production in fermented soybean. Soybeans are a good substrate for the production of functional foods because of their well-suited cultivation and nutritional quality. The results of this study provide a good explanation for the high folate production observed during the fermentation of soybeans.

Pro-resolving lipid mediators in vascular disease.

Unresolved inflammation is central to the pathophysiology of commonly occurring vascular diseases such as atherosclerosis, aneurysm, and deep vein thrombosis - conditions that are responsible for considerable morbidity and mortality. Surgical or catheter-based procedures performed on affected blood vessels induce acute-on-chronic inflammatory responses. The resolution of vascular inflammation is an important driver of vessel wall remodeling and functional recovery in these clinical settings. Specialized pro-resolving lipid mediators (SPMs) derived from omega-3 polyunsaturated fatty acids orchestrate key cellular processes driving resolution and a return to homeostasis. The identification of their potent effects in classic animal models of sterile inflammation triggered interest in their vascular properties. Recent studies have demonstrated that SPMs are locally synthesized in vascular tissues, have direct effects on vascular cells and their interactions with leukocytes, and play a protective role in the injury response. Early translational work has established the potential for SPMs as vascular therapeutics, and as candidate biomarkers in vascular disease. Further investigations are needed to understand the molecular and cellular mechanisms of resolution in the vasculature, to improve tools for clinical measurement, and to better define the potential for "resolution therapeutics" in vascular patients.

Resolution of vascular injury: Specialized lipid mediators and their evolving therapeutic implications.

Acute vascular injury occurs in a number of important clinical contexts, including spontaneous disease-related events (e.g. plaque rupture, thrombosis) and therapeutic interventions such as angioplasty, stenting, or bypass surgery. Endothelial cell (EC) disruption exposes the underlying matrix, leading to a rapid deposition of platelets, coagulation proteins, and leukocytes. A thrombo-inflammatory response ensues characterized by leukocyte recruitment, vascular smooth muscle cell (VSMC) activation, and the elaboration of cytokines, reactive oxygen species and growth factors within the vessel wall. A resolution phase of vascular injury may be described in which leukocyte efflux, clearance of debris, and re-endothelialization occurs. VSMC migration and proliferation leads to the development of a thickened neointima that may lead to lumen compromise. Subsequent remodeling involves matrix protein deposition, and return of EC and VSMC to quiescence. Recent studies suggest that specialized pro-resolving lipid mediators (SPM) modulate key aspects of this response, and may constitute an endogenous homeostatic pathway in the vasculature. SPM exert direct effects on vascular cells that counteract inflammatory signals, reduce leukocyte adhesion, and inhibit VSMC migration and proliferation. These effects appear to be largely G-protein coupled receptor-dependent. Across a range of animal models of vascular injury, including balloon angioplasty, bypass grafting, and experimental aneurysm formation, SPM accelerate repair and reduce lesion formation. With bioactivity in the pM-nM range, a lack of discernible cytotoxicity, and a spectrum of vasculo-protective properties, SPM represent a novel class of vascular therapeutics. This review summarizes current research in this field, including a consideration of critical next steps and challenges in translation.

Biosynthesis of proresolving lipid mediators by vascular cells and tissues.

Recent evidence suggests that specialized proresolving lipid mediators (SPMs) generated from docosahexaenoic acid (DHA) can modulate the vascular injury response. However, cellular sources for these autacoids within the vessel wall remain unclear. Here, we investigated whether isolated vascular cells and tissues can produce SPMs and assessed expression and subcellular localization of the key SPM biosynthetic enzyme 5-lipoxygenase (LOX) in vascular cells. Intact human arteries incubated with DHA ex vivo produced 17-hydroxy DHA (17-HDHA) and D-series resolvins, as assessed by liquid chromatography-tandem mass spectrometry. Addition of 17-HDHA to human arteries similarly increased resolvin production. Primary cultures of human saphenous vein endothelial cells (ECs) and vascular smooth muscle cells (VSMCs) converted 17-HDHA to SPMs, including resolvin D1 (RvD1) and other D-series resolvins and protectins. This was accompanied by a rapid translocation of 5-LOX from nucleus to cytoplasm in both ECs and VSMCs, potentially facilitating SPM biosynthesis. Conditioned medium from cells exposed to 17-HDHA inhibited monocyte adhesion to TNF-α-stimulated EC monolayers. These downstream effects were partially reversed by antibodies against the RvD1 receptors ALX/FPR2 and GPR32. These results suggest that autocrine and/or paracrine signaling via locally generated SPMs in the vasculature may represent a novel homeostatic mechanism of relevance to vascular health and disease.-Chatterjee, A., Komshian, S., Sansbury, B. E., Wu, B., Mottola, G., Chen, M., Spite, M., Conte, M. S. Biosynthesis of proresolving lipid mediators by vascular cells and tissues.

Priming ammonia lyases and aminomutases for industrial and therapeutic applications.

Ammonia lyases (AL) and aminomutases (AM) are emerging in green synthetic routes to chiral amines and an AL is being explored as an enzyme therapeutic for treating phenylketonuria and cancer. Although the restricted substrate range of the wild-type enzymes limits their widespread application, the non-reliance on external cofactors and direct functionalization of an olefinic bond make ammonia lyases attractive biocatalysts for use in the synthesis of natural and non-natural amino acids, including ß-amino acids. The approach of combining structure-guided enzyme engineering with efficient mutant library screening has extended the synthetic scope of these enzymes in recent years and has resolved important mechanistic issues for AMs and ALs, including those containing the MIO (4-methylideneimidazole-5-one) internal cofactor.

[The anti-injury effect of breviscapine injection on the hypoxic ischemic brain damage of neonatal rats and the expression of Bcl-2 and Bax].

OBJECTIVE: To observe the protective effect of Breviscapine injection on the hypoxic ischemic brain damage of neonatal rats, and the expression of Bcl-2 and Bax. METHODS: In this experiment 7-day-old newborn rat with hypoxic-ischemic brain damage model was used and divided into four groups: sham group, model group, control with sterile water for injection group and Breviscapine injection group. Breviscapine injection group was divided into large, medium, and small doses. Used thionin staining and immunohistochemical staining to assay the neuronal density, histological grade, and the expresssion of Bcl-2 and Bax protein in the CA1 hippocampus of each group , the number of positive cells and the integral optical density (IOD) of the immunostaining on Bcl-2, Bax protein expression in the CA1 hippocampus. RESULTS: Sham group, there was no significant neuronal damage and no obvious positive cells of Bcl-2 and Bax in the CA1 hippocampus. In model group and control with sterile water for injection group, the level of Bcl-2, Bax expression peaked at 3 d after hypoxic-ischemic brain damage (HIBD) (P < 0.05 vs other groups), the value of neuronal density (ND) was decreased, and histological grade (HG) was increased compared with that in the sham group (P < 0.05). Breviscapine injection group, compared with control with sterile water for injection group, the expression of Bcl-2 protein was further increased, IOD value increased, while the expression of Bax protein was decreased, IOD value decreased, the value of ND increased, and HG decreased. CONCLUSION: Breviscapin injection maybe reduce the delayed neuronal death, and reduce the apoptosis of neuron after severe brain injury through improving the expression of Bcl-2 protein and inhibiting expression of Bax. The study would provide a fine theoretical foundation for clinical therapy of neonatal HIBD.

Underutilization of parathyroidectomy in elderly patients with primary hyperparathyroidism.

CONTEXT: Primary hyperparathyroidism (PHPT) disproportionately affects older patients, who may face higher thresholds for surgical intervention compared to young patients. OBJECTIVE: The aim was to examine for differences in the utilization of parathyroidectomy attributable to age. DESIGN: We conducted a retrospective cohort study. PARTICIPANTS: Patients with biochemically diagnosed PHPT during the years 1995-2008 were identified within an integrated health care delivery system in Southern California encompassing approximately 3 million individuals. MAIN OUTCOME MEASURES: The outcome measures were parathyroidectomy (PTx) and time interval to surgery. RESULTS: We found 3388 patients with PHPT, 964 (28%) of whom underwent PTx. Patients aged 60+ yr comprised 60% of the study cohort. The likelihood of PTx decreased linearly among patients aged 60+ when compared to patients aged 50-59, an effect that persisted in multivariate analysis: odds ratio 0.68 for ages 60-69 (P < 0.05); 0.41 for ages 70-79 (P < 0.0001), and 0.11 for age 80+ (P < 0.0001). The PTx rate for patients aged 70+ was 14%. Among patients meeting 2002 consensus criteria for surgical treatment, 45% of those aged 60-69 and 24% of those aged 70+ underwent PTx. A Cox proportional hazards model showed that patients aged 60+ experienced significantly longer delays from diagnosis to surgery compared to young patients (P < 0.0001). CONCLUSIONS: PHPT is undertreated in the elderly. We observed a progressive age-related decline in PTx rate that renders patients aged 70+ unlikely to have definitive treatment, irrespective of comorbidity and eligibility for surgery.