Activation of the serine-threonine kinase Akt promotes the survival and proliferation of various cancers. Hypoxia promotes the resistance of tumor cells to specific therapies. We therefore explored a possible link between hypoxia and Akt activity. We found that Akt was prolyl-hydroxylated by the oxygen-dependent hydroxylase EglN1. The von Hippel–Lindau protein (pVHL) bound directly to hydroxylated Akt and inhibited Akt activity. In cells lacking oxygen or functional pVHL, Akt was activated to promote cell survival and tumorigenesis. We also identified cancer-associated Akt mutations that impair Akt hydroxylation and subsequent recognition by pVHL, thus leading to Akt hyperactivation. Our results show that microenvironmental changes, such as hypoxia, can affect tumor behaviors by altering Akt activation, which has a critical role in tumor growth and therapeutic resistance.
Pretreatment NLR and PLR can be independent prognostic factors for patients with NPC. © 2015 Wiley Periodicals, Head Neck 38: E1332-E1340, 2016.
Nasopharyngeal carcinoma (NPC) shows the highest invasive and metastatic features among head and neck cancers. Distant metastasis remains the predominant mode of treatment failure in NPC patients. The role of interleukin-6 (IL-6) in NPC progression is not fully understood. In this study, we explored whether IL-6 could promote the migration and invasion activity of NPC cell lines, as well as whether the effect of IL-6 on cell migration and invasion is mediated through regulating the expression of matrix metalloproteinase-2 (MMP-2) and MMP-9. Our results revealed that IL-6 and its receptors are broadly expressed in various NPC cell lines including HNE1, HONE1, CNE1, CNE1-LMP1 and 5-8F. Exogenous IL-6 enhanced cell proliferation slightly, but promoted cell migration and invasion significantly in both HNE1 and CNE1-LMP1 cell lines. In addition, an elevation in the expression of MMP-2 and MMP-9 could be induced by IL-6 stimulation. On the contrary, combining treatment with monoclonal anti-human IL-6R antibody (anti-IL-6R mAb) resulted in decreased proliferation, migration and invasion capabilities of NPC cells. Anti-IL-6R mAb also inhibited the expression of MMP-2 and MMP-9 in IL-6-stimulated HNE1 and CNE1-LMP1 cells. In summary, our data suggested that IL-6 mainly promotes the cell migration and invasion of NPC cells. The effect of IL-6 on cell migration and invasion may be mediated through regulation of the expression of MMP-2 and MMP-9. Thus, IL-6 or its related signaling pathways may be a promising target for preventing and inhibiting NPC metastasis.
Aseries of Mn I complexes containing lutidine-based chiral pincer ligands with modular and tunable structures has been developed. The complex shows unprecedentedly high activities (up to 9800 TON; TON = turnover number), broad substrate scope (81 examples), good functional-group tolerance,a nd excellent enantioselectivities (85-98 %e e) in the hydrogenation of various ketones.T hese aspects are rare in earth-abundant metal catalyzedhydrogenations.T he utility of the protocol have been demonstrated in the asymmetric synthesis of av ariety of key intermediates for chiral drugs. Preliminary mechanistic investigations indicate that an outersphere mode of substrate-catalyst interactions probably dominates the catalysis.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.
DETQ, an allosteric potentiator of the dopamine D1 receptor, was tested in therapeutic models that were known to respond to D1 agonists. Because of a species difference in affinity for DETQ, all rodent experiments used transgenic mice expressing the human D1 receptor (hD1 mice). When given alone, DETQ reversed the locomotor depression caused by a low dose of reserpine. DETQ also acted synergistically with L-DOPA to reverse the strong hypokinesia seen with a higher dose of reserpine. These results indicate potential as both monotherapy and adjunct treatment in Parkinson's disease. DETQ markedly increased release of both acetylcholine and histamine in the prefrontal cortex, and increased levels of histamine metabolites in the striatum. In the hippocampus, the combination of DETQ and the cholinesterase inhibitor rivastigmine increased ACh to a greater degree than either agent alone. DETQ also increased phosphorylation of the AMPA receptor (GluR1) and the transcription factor CREB in the striatum, consistent with enhanced synaptic plasticity. In the Y-maze, DETQ increased arm entries but (unlike a D1 agonist) did not reduce spontaneous alternation between arms at high doses. DETQ enhanced wakefulness in EEG studies in hD1 mice and decreased immobility in the forced-swim test, a model for antidepressant-like activity. In rhesus monkeys, DETQ increased spontaneous eye-blink rate, a measure that is known to be depressed in Parkinson's disease. Together, these results provide support for potential utility of D1 potentiators in the treatment of several neuropsychiatric disorders, including Parkinson's disease, Alzheimer's disease, cognitive impairment in schizophrenia, and major depressive disorder.
Telocytes (Tcs) are cells with telopodes (Tps), which are very long cellular extensions with alternating thin segments (podomers) and dilated bead-like thick regions known as podoms. Tcs are a distinct category of interstitial cells and have been identified in many mammalian organs including heart, lung and kidney. The present study investigates the existence, ultrastructure, distribution and contacts of Tcs with surrounding cells in the uterus (shell gland) of the oviduct of the Chinese soft-shelled turtle, Pelodiscus sinensis. Samples from the uterine segment of the oviduct were examined by transmission electron microscopy. Tcs were mainly located in the lamina propria beneath the simple columnar epithelium of the uterus and were situated close to nerve endings, capillaries, collagen fibres and secretory glands. The complete morphology of Tcs and Tps was clearly observed and our data confirmed the existence of Tcs in the uterus of the Chinese soft-shelled turtle Pelodiscus sinensis. Our results suggest these cells contribute to the function of the secretory glands and contraction of the uterus.
2509 Background: As a promising approach for some cancers, chimeric antigen receptor T cell therapy has limited success in solid tumors. Claudin18.2 (CLDN 18.2) is a stomach-specific isoform of Claudin-18, and highly expressed in gastric and pancreatic adenocarcinoma, the advanced form of both of which have urgent unmet medical needs. We previously developed and demonstrated ability of CLDN 18.2-specific CAR (CAR-CLDN18.2) T cells to eradicate CLDN 18.2-positive gastric cancer xenografts without obvious on-target off-tumor toxicity (Huang J. JNCI 2018). Methods: In this single-arm, open-label, first-in-human phase I pilot study (NCT03159819) to investigate the safety and explore the efficacy of the autologous CAR-CLDN18.2 T cells, patients with confirmed CLDN 18.2 positive advanced gastric or pancreatic adenocarcinoma aged 18 to 70 years received 1 or more cycles of CAR-CLDN18.2 T cell infusion(s) after lymphodepletion pretreatment (fludarabine and cyclophosphamide, with or without nab-paclitaxel) until disease progression or presence of intolerable toxicity. Adverse Event (AE) grade categorization is according to CTCAE 4.0, and tumor response was assessed per RECIST 1.1. Results: As of November 30th, 2018, 12 subjects with metastatic adenocarcinoma (7 gastric and 5 pancreatic) were treated with 1–5 cycles (total of 0.5 - 55 X 108) of CAR-positive T cells infusions. There were no serious adverse events, treatment-related death or severe neurotoxicity occurred in the study. No grade 4 AEs except for decreased lymphocytes, neutrophils and white blood cells. All cytokine release syndromes observed were grade 1 or 2. Among the 11 evaluable subjects, 1 achieved a complete response (gastric adenocarcinoma), 3 had partial responses (2 gastric adenocarcinomas and 1 pancreatic adenocarcinoma), 5 had stable disease and 2 had progression of disease. The total objective response rate was 33.3%, with median PFS of 130 days estimated using Kaplan-Meier method [95% CI (38, 230)]. Conclusions: This clinical study indicated that CAR-CLDN18.2 T cell therapy were safe and well tolerated and may have promising therapeutic efficacy in patients with advanced gastric and pancreatic adenocarcinoma. Clinical trial information: NCT03159819.
Copper plays pivotal roles in metabolic homoeostasis, but its potential role in human tumorigenesis is not well defined. Here, it is revealed that copper activates the phosphoinositide 3-kinase (PI3K)-protein kinase B (PKB, also termed AKT) oncogenic signaling pathway to facilitate tumorigenesis. Mechanistically, copper binds 3-phosphoinositide dependent protein kinase 1 (PDK1), in turn promotes PDK1 binding and subsequently activates its downstream substrate AKT to facilitate tumorigenesis. Blocking the copper transporter 1 (CTR1)-copper axis by either depleting CTR1 or through the use of copper chelators diminishes the AKT signaling and reduces tumorigenesis. In support of an oncogenic role for CTR1, the authors find that CTR1 is abnormally elevated in breast cancer, and is subjected by NEDD4 like E3 ubiquitin protein ligase (Nedd4l)-mediated negative regulation through ubiquitination and subsequent degradation. Accordingly, Nedd4l displays a tumor suppressive function by suppressing the CTR1-AKT signaling. Thus, the findings identify a novel regulatory crosstalk between the Nedd4l-CTR1-copper axis and the PDK1-AKT oncogenic signaling, and highlight the therapeutic relevance of targeting the CTR1-copper node for the treatment of hyperactive AKT-driven cancers.
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