BACE1 is a key protease controlling the formation of amyloid ␤, a peptide hypothesized to play a significant role in the pathogenesis of Alzheimer's disease (AD). Therefore, the development of potent and selective inhibitors of BACE1 has been a focus of many drug discovery efforts in academiaandindustry.Herein,wereportthenonclinicalandearlyclinicaldevelopmentofLY2886721,aBACE1activesiteinhibitorthatreached phase 2 clinical trials in AD. LY2886721 has high selectivity against key off-target proteases, which efficiently translates in vitro activity into robust in vivo amyloid ␤ lowering in nonclinical animal models. Similar potent and persistent amyloid ␤ lowering was observed in plasma and lumbar CSF when single and multiple doses of LY2886721 were administered to healthy human subjects. Collectively, these data add support for BACE1 inhibition as an effective means of amyloid lowering and as an attractive target for potential disease modification therapy in AD.

Background: Chemotaxis requires excitatory and inhibitory signals at the front and back of cells. PANX1 and P2Y 2 receptors provide local excitation at the front. Results: We found that PANX1 triggers A 2A receptor activation and inhibits chemotactic signaling at the back. Conclusion: PANX1 thus integrates excitatory and inhibitory signals that regulate chemotaxis at the front and back of cells. Significance: These findings suggest new strategies to modulate neutrophil chemotaxis.

Searching for efficacious and safe agents for the chemoprevention and therapy of prostate cancer has become the top priority of research. The objective of this study was to determine the effects of a group of tanshinones from a Chinese herb Salvia Miltiorrhiza, cryptotanshinone (CT), tanshinone IIA (T2A) and tanshinone I (T1) on prostate cancer. The in vitro studies showed that these tanshinones inhibited the growth of human prostate cancer cell lines in a dose‐dependent manner via cell cycle arrest and apoptosis induction. Among three compounds, T1 had the most potent activity with IC50s around 3–6 μM. On the other hand, tanshinones had much less adverse effects on the growth of normal prostate epithelial cells. The epigenetic pathway focused array assay identified Aurora A kinase as a possible target of tanshinone actions. The expression of Aurora A was overexpressed in prostate cancer cell lines. Moreover, knockdown of Aurora A in prostate cancer cells significantly decreased cell growth. Tanshinones significantly downregulated the Aurora A expression, suggesting Aurora A may be a functional target of tanshinones. Tanshinones, especially T1, also showed potent anti‐angiogenesis activity in vitro and in vivo. Furthermore, T1 inhibited the growth of DU145 prostate tumor in mice associated with induction of apoptosis, decrease of proliferation, inhibition of angiogenesis and downregulation of Aurora A, whereas it did not alter food intake or body weight. Our results support that T1 may be an efficacious and safe chemopreventive or therapeutic agent against prostate cancer progression.

BackgroundExtracellular adenosine triphosphate (ATP) functions as a novel danger signal that boosts antitumor immunity and can also directly kill tumor cells. We have previously reported that chronic exposure of tumor cells to ATP provokes P2X7-mediated tumor cell death, by as yet incompletely defined molecular mechanisms.Methodology/Principal FindingsHere, we show that acute exposure of tumor cells to ATP results in rapid cytotoxic effects impacting several aspects of cell growth/survival, leading to inhibition of tumor growth in vitro and in vivo. Using agonist and antagonist studies together with generation of P2X7 deficient tumor cell lines by lentiviral shRNA delivery system, we confirm P2X7 to be the central control node transmitting extracellular ATP signals. We identify that downstream intracellular signaling regulatory networks implicate two signaling pathways: the known P2X7-PI3K/AKT axis and remarkably a novel P2X7-AMPK-PRAS40-mTOR axis. When exposed to high levels of extracellular ATP, these two signaling axes perturb the balance between growth and autophagy, thereby promoting tumor cell death.ConclusionsOur study defines novel molecular mechanisms underpinning the antitumor actions of P2X7 and provides a further rationale for purine-based drugs in targeted cancer therapy.

Background: Autocrine purinergic signaling regulates T cell function. Results: We found that mitochondria are the source of ATP that drives these signaling mechanisms. Conclusion: Mitochondria are the gate-keepers of T cell function that control purinergic signaling and T cell activation. Significance: These findings suggest that mitochondria could be therapeutic targets to modulate T cell responses.

Numerous studies show that nonsteroidal anti-inflammatory drugs (NSAIDs) are effective in chemoprevention or treatment of cancer. Nevertheless, the mechanisms underlying these antineoplastic effects remain poorly understood. Here, we report that induction of the cancer-specific proapoptotic cytokine melanoma differentiation associated gene-7/interleukin-24 (MDA-7/IL-24) by several NSAIDs is an essential step for induction of apoptosis and G 2 -M growth arrest in cancer cells in vitro and inhibition of tumor growth in vivo. We also show that MDA-7/IL-24-dependent up-regulation of growth arrest and DNA damage inducible 45 a (GADD45a) and GADD45g gene expression is sufficient for cancer cell apoptosis via c-Jun NH 2 -terminal kinase (JNK) activation and growth arrest induction through inhibition of Cdc2-cyclin B checkpoint kinase. Knockdown of GADD45a and GADD45g transcription by small interfering RNA abrogates apoptosis and growth arrest induction by the NSAID treatment, blocks JNK activation, and restores Cdc2-cyclin B kinase activity. Our results establish MDA-7/IL-24 and GADD45A and GADD45; as critical mediators of apoptosis and growth arrest in response

Liver cancer is associated with chronic inflammation, which is linked to immune dysregulation, disordered metabolism and aberrant cell proliferation. CD39/ENTPD1 is an ectonucleotidase that regulates extracellular nucleotide/nucleoside concentrations by scavenging nucleotides to ultimately generate adenosine. These properties inhibit anti tumor immune responses and promote angiogenesis, being permissive for the growth of transplanted tumors. Here, we show Cd39 deletion promotes development of both induced and spontaneous autochthonous liver cancer in mice. Loss of Cd39 results in higher concentrations of extracellular nucleotides, which stimulate proliferation of hepatocytes, abrogate autophagy and disrupt glycolytic metabolism. Constitutive activation of Ras-MAPK and mTOR-S6K1 pathways occurs in both quiescent Cd39 null hepatocytes in vitro and liver tissues in vivo. Exogenous ATP boosts these signaling pathways, while rapamycin inhibits such aberrant responses in hepatocytes. Conclusions Deletion of Cd39 and resulting changes in disordered purinergic signaling perturb hepatocellular metabolic/proliferative responses, paradoxically resulting in malignant transformation. These findings might impact adjunctive therapies for cancer. Lastly, our studies indicate that the biology of autochthonous and transplanted tumors is quite distinct.

Objective-The aim of this study was to determine the effect of DRIs on hot flash symptoms in menopausal women.Design-This was a randomized, double-blind, placebo-controlled trial of menopausal women, aged 38 to 60 years, who experienced 4 to 14 hot flashes per day. After a 1-week run-in period, a total of 190 menopausal women were randomized to receive a placebo or 40 or 60 mg/day of a DRI for 12 weeks. The primary outcome was the mean changes from baseline to week 12 in the frequency of hot flashes recorded in the participant diary. The secondary outcomes included changes in quality of life and hormonal profiles.Results-A total of 147 women (77%) completed the study. It was found that 40 and 60 mg of DRI improved hot flash frequency and severity equally. At 8 weeks hot flash frequency was reduced by 43% in the 40-mg DRI group and by 41% in the 60-mg DRI group, compared with 32% in the placebo group (P = not significant vs placebo). The corresponding numbers for 12 weeks were 52%, 51%, and 39%, respectively (P = 0.07 and 0.09 vs placebo). When comparing the two treatment groups with the placebo group, there were significant reductions in mean daily hot flash frequency. The supplement (either 40 or 60 mg) reduced hot flash frequency by 43% at 8 weeks (P = 0.1) and 52% at 12 weeks (P = 0.048) but did not cause any significant changes in endogenous sex hormones or thyroid hormones. Menopausal quality of life improved in all three groups, although there were no statistically significant differences between groups.Conclusions-DRI supplementation may be an effective and acceptable alternative to hormone treatment for menopausal hot flashes. Although hormone therapy (HT) is the most effective treatment for the relief of hot flashes to date, evidence suggests that long-term use of HT may increase the risk of developing certain medical disorders. The data from the Women's Health Initiative showed an increased risk of coronary heart disease, stroke, pulmonary embolism, and breast cancer with estrogen + progestogen therapy (conjugated equine estrogens + medroxyprogesterone acetate) after a mean of 5.2 years of follow-up. 3 Estrogen+ progestogen therapy was associated with a 24% increased risk of coronary heart disease. 4 Thus, safe and effective alternatives are needed. KeywordsRecently interest has arisen in isoflavones as a potential therapy for menopausal hot flashes.Isoflavones are one of several classes of phytoestrogens, compounds that exert both estrogenic and antiestrogenic properties. Daidzein and genistein are isoflavones that are found in rich supply in soybeans and soy products. Available data on isoflavones for the treatment of menopausal symptoms have been inconclusive; studies with positive results have reported only a slight improvement. Nonetheless, there are no studies showing harmful effects of isoflavones on menopausal symptoms. This inconsistency may, in part, be due to differences in methods used to isolate isoflavones, concentrations of bioavailable isoflavones, and the composition of isoflav...