Integrated gene co-expression network analysis and experimental validation revealed potential targets of human urine extract CDA-II in treating chronic myeloid leukemia.

BACKGROUND: Cell differentiation agent II (CDA-II) exhibits potent anti-proliferative and apoptosis-inducing properties against a variety of cancer cells. However, its mechanism of action in chronic myeloid leukemia (CML) remains unclear. METHODS: Cell counting Kit 8 (CCK-8) and flow cytometry were used to investigate the effects of CDA-II on the biological characteristics of K562 cells. Gene (mRNA and lncRNA) expression profiles were analyzed by bioinformatics to screen differentially expressed genes and to perform enrichment analysis. The Pearson correlation coefficients of lncRNAs and mRNAs were calculated using gene expression values, and a lncRNA/mRNA co-expression network was constructed. The MCODE and cytoHubba plugins were used to analyze the co-expression network. RESULTS: The Results, derived from CCK-8 and flow cytometry, indicated that CDA-II exerts dual effects on K562 cells: it inhibits their proliferation and induces apoptosis. From bioinformatics analysis, we identified 316 mRNAs and 32 lncRNAs. These mRNAs were predominantly related to the meiotic cell cycle, DNA methylation, transporter complex and peptidase regulator activity, complement and coagulation cascades, protein digestion and absorption, and cell adhesion molecule signaling pathways. The co-expression network comprised of 163 lncRNA/mRNA interaction pairs. Notably, our analysis results implicated clustered histone gene families and five lncRNAs in the biological effects of CDA-II on K562 cells. CONCLUSION: This study highlights the hub gene and lncRNA/mRNA co-expression network as crucial elements in the context of CDA-II treatment of CML. This insight not only enriches our understanding of CDA-II's mechanism of action but also might provide valuable clues for subsequent experimental studies of CDA-II, and potentially contribute to the discovery of new therapeutic targets for CML.

Visual analysis of the research literature on extracorporeal membrane oxygenation-assisted support for respiratory failure based on CiteSpace and VOSviewer: a 20-year study.

Background: This study aims to visually assess the bibliometric status, current hotspots, and development trends in the field of extracorporeal membrane oxygenation (ECMO)-assisted support for respiratory failure through an examination of articles pertaining to ECMO-assisted support for respiratory failure. Methods: A search was conducted on pertinent literature in the domain of ECMO-assisted support for respiratory failure published from 2003 to 2023, utilizing the Web of Science Core Collection (WOSCC) database. A bibliometric analysis was conducted using CiteSpace and VOSviewer visualization software to identify and assess associations between keywords, countries, institutions, authors, journals, and references. Results: The present study incorporated a compilation of 1,901 pertinent articles. The United States published the maximum number of research articles in this field, and was closely followed by Germany and China. Furthermore, the University of Michigan was the leading institution in ECMO research. In this context, Daniel Brodie, an American expert, significantly contributed to this field and had published 107 related articles on the subject. Concurrently, active collaboration among ECMO researchers was also observed. Asaio Journal was the most prolific contributor, and Giles J. Peek, 2009, published in Lancet, comprised the most cited article in the field. Additionally, the analysis of keywords could be divided into three categories: (I) neonatal ECMO; (II) complications of ECMO; (III) ECMO application in coronavirus disease 2019 (COVID-19); (IV) application of point-of-care ultra sound in ECMO. Conclusions: This study employed CiteSpace and VOSviewer to conduct a systematic literature review on ECMO-assisted support for respiratory failure from 2003 to 2023 in the Web of Science core database. The research outcomes in this domain were presented, offering researchers references for them to gain an accurate understanding of the current state of research and emerging trends in this field.

Diagnosis of leptospira by metagenomics next-generation sequencing with extracorporeal membrane oxygenation support: a case report.

BACKGROUND: Leptospirosis is an infectious disease caused by pathogenic Leptospira spp., which could result in severe illnesses. Indirect contact with these pathogens is more common. Individuals could contract this disease through contact with contaminated water or during floods. In this case, we present the details of a 40-year-old male pig farmer who suffered from severe pulmonary hemorrhagic leptospirosis and multiple organ failure. The diagnosis of leptospirosis was confirmed through metagenomics next-generation sequencing (mNGS) while the patient received extracorporeal membrane oxygenation (ECMO) support, and antibiotic treatment was adjusted accordingly. The patient underwent comprehensive treatment and rehabilitation in the intensive care unit. CONCLUSION: This case illustrates the importance of early diagnosis and treatment of leptospirosis. While obtaining the epidemiological history, second-generation metagenomics sequencing was utilized to confirm the etiology. The prompt initiation of ECMO therapy provided a crucial window of opportunity for addressing the underlying cause. This case report offers valuable insights for diagnosing patients with similar symptoms.

Efficacy Evaluation of Zoledronic Acid Combined with Chemotherapy in the Treatment of Lung Cancer Spinal Metastases on Computed Tomography Images on Intelligent Algorithms.

To analyze the effectiveness and safety of zoledronic acid combined with chemotherapy for lung cancer spinal metastases, 96 patients with lung cancer spinal metastases were averagely classified into the experimental group (gemcitabine, cisplatin, and zoledronic acid) and the control group (gemcitabine and cisplatin). An optimized noise variance estimation algorithm (OMAPB) was proposed based on the maximum a posteriori Bayesian method (MAPB), and the algorithm was applied to the patient's computed tomography (CT) scan. The results indicated that in terms of curative effect, the number of complete remission (CR), partial remission (PR) cases, effective rate, and clinical benefit rate of the test group was significantly higher than those of the control group. The number of progress disease (PD) cases was significantly lower than that of the control group (P < 0.05). The disease progression time of the test group patients was 6.2 months, and the disease progression time of the control group patients was 3.7 months (P < 0.05). The test group patients had 8 cases of bone marrow suppression and gastrointestinal reactions after treatment. In the test group, there were 8 cases of bone marrow suppression, 9 cases of gastrointestinal reaction, 3 cases of fever, 4 cases of pain, and 2 cases of hair loss. The patients in the control group were complicated with bone marrow suppression in 14 cases, gastrointestinal reaction in 17 cases, fever in 5 cases, pain in 4 cases, and hair loss in 6 cases. The difference was statistically significant (P < 0.05). It showed that zoledronic acid combined with chemotherapy could effectively improve the treatment efficiency and clinical benefit rate of patients with lung cancer spinal metastases, prolong the progression of the disease, reduce the degree of bone tissue damage, and would not increase chemotherapy adverse events.

Development and validation of a predictive model for feeding intolerance in intensive care unit patients with sepsis.

BACKGROUND: Feeding intolerance in patients with sepsis is associated with a lower enteral nutrition (EN) intake and worse clinical outcomes. The aim of this study was to develop and validate a predictive model for enteral feeding intolerance in the intensive care unit patients with sepsis. METHODS: In this dual-center, retrospective, case-control study, a total of 195 intensive care unit patients with sepsis were enrolled from June 2018 to June 2020. Data of 124 patients for 27 clinical indicators from one hospital were used to train the model, and data from 71 patients from another hospital were used to assess the external predictive performance. The predictive models included logistic regression, naive Bayesian, random forest, gradient boosting tree, and deep learning (multilayer artificial neural network) models. RESULTS: Eighty-six (44.1%) patients were diagnosed with enteral feeding intolerance. The deep learning model achieved the best performance, with areas under the receiver operating characteristic curve of 0.82 (95% confidence interval = 0.74-0.90) and 0.79 (95% confidence interval = 0.68-0.89) in the training and external sets, respectively. The deep learning model showed good calibration; based on the decision curve analysis, the model's clinical benefit was considered useful. Lower respiratory tract infection was the most important contributing factor, followed by peptide EN and shock. CONCLUSIONS: The new prediction model based on deep learning can effectively predict enteral feeding intolerance in intensive care unit patients with sepsis. Simple clinical information such as infection site, nutrient type, and septic shock can be useful in stratifying a septic patient's risk of EN intolerance.

Effect of artificial liver blood purification treatment on the survival of critical ill COVID-19 patients.

Our aim was to investigate the effect of artificial liver blood purification treatment on the survival of severe/critical patients with coronavirus disease 2019 (COVID-19). A total of 101 severe and critical patients with coronavirus SARS-CoV-2 infection were enrolled in this open, case-control, multicenter, prospective study. According to the patients' and their families' willingness, they were divided into two groups. One was named the treatment group, in which the patients received artificial liver therapy plus comprehensive treatment (n = 50), while the other was named the control group, in which the patients received only comprehensive treatment (n = 51). Clinical data and laboratory examinations, as well as the 28-day mortality rate, were collected and analyzed. Baseline data comparisons on average age, sex, pre-treatment morbidity, initial symptoms, vital signs, pneumonia severity index score, blood routine examination and biochemistry indices etc. showed no difference between the two groups. Cytokine storm was detected, with a significant increase of serum interleukin-6 (IL-6) level. The serum IL-6 level decreased from 119.94 to 20.49 pg/mL in the treatment group and increased from 40.42 to 50.81 pg/mL in the control group (P < .05), indicating that artificial liver therapy significantly decreased serum IL-6. The median duration of viral nucleic acid persistence was 19 days in the treatment group (ranging from 6 to 67 days) and 17 days in the control group (ranging from 3 to 68 days), no significant difference was observed (P = .36). As of 28-day follow-up,17 patients in the treatment group experienced a median weaning time of 24 days, while 11 patients in the control group experienced a median weaning time of 35 days, with no significant difference between the two groups (P = .33). The 28-day mortality rates were 16% (8/50) in the treatment group and 50.98% (26/51) in the control group, with a significant difference (z = 3.70, P < .001). Cytokine storm is a key factor in the intensification of COVID-19 pneumonia. The artificial liver therapy blocks the cytokine storm by clearing inflammatory mediators, thus preventing severe cases from progressing to critically ill stages and markedly reducing short-term mortality.

Transient appearance of EDTA dependent pseudothrombocytopenia in a patient with 2019 novel coronavirus pneumonia.

EDTA dependent pseudothrombocytopenia (EDTA-PCTP) is a phenomenon that characterized by a spurious decrease of platelets in vitro due to the aggregation of platelets in EDTA anticoagulant blood samples. We report the first case of a transient appearance of EDTA-PCTP in a patient with 2019 novel coronavirus pneumonia (COVID-19). A 59-year-old woman was admitted to the isolated ward for severe type of 2019 novel coronavirus pneumonia. At the time of admission, her platelet count was in a normal range. Two days later, her platelet count decreased gradually without any signs or symptoms of bleeding. Since the peripheral blood smear showed a platelet aggregation, a blood sample anticoagulanted with citrate was tested and the number of platelet was normal. The phenomenon disappeared after 17 days when the patient was cured. This case emphasized the importance of peripheral blood smear and clinical manifestation, especially in the differential diagnosis of thrombocytopenia.

Influence of Daytime LED Light Exposure on Circadian Regulatory Dynamics of Metabolism and Physiology in Mice.

Light is a potent biologic force that profoundly influences circadian, neuroendocrine, and neurobehavioral regulation in animals. Previously we examined the effects of light-phase exposure of rats to white light-emitting diodes (LED), which emit more light in the blue-appearing portion of the visible spectrum (465 to 485 nm) than do broad-spectrum cool white fluorescent (CWF) light, on the nighttime melatonin amplitude and circadian regulation of metabolism and physiology. In the current studies, we tested the hypothesis that exposure to blue-enriched LED light at day (bLAD), compared with CWF, promotes the circadian regulation of neuroendocrine, metabolic, and physiologic parameters that are associated with optimizing homeostatic regulation of health and wellbeing in 3 mouse strains commonly used in biomedical research (C3H [melatonin-producing], C57BL/6, and BALB/c [melatonin-non-producing]). Compared with male and female mice housed for 12 wk under 12:12-h light:dark (LD) cycles in CWF light, C3H mice in bLAD evinced 6-fold higher peak plasma melatonin levels at the middark phase; in addition, high melatonin levels were prolonged 2 to 3 h into the light phase. C57BL/6 and BALB/c strains did not produce nighttime pineal melatonin. Body growth rates; dietary and water intakes; circadian rhythms of arterial blood corticosterone, insulin, leptin, glucose, and lactic acid; pO2 and pCO2; fatty acids; and metabolic indicators (cAMP, DNA, tissue DNA 3H-thymidine incorporation, fat content) in major organ systems were significantly lower and activation of major metabolic signaling pathways (mTOR, GSK3ß, and SIRT1) in skeletal muscle and liver were higher only in C3H mice in bLAD compared with CWF. These data show that exposure of C3H mice to bLAD compared with CWF has a marked positive effect on the circadian regulation of neuroendocrine, metabolic, and physiologic parameters associated with the promotion of animal health and wellbeing that may influence scientific outcomes. The absence of enhancement in amelatonic strains suggests hyperproduction of nighttime melatonin may be a key component of the physiology.

Epigenetic inhibition of the tumor suppressor ARHI by light at night-induced circadian melatonin disruption mediates STAT3-driven paclitaxel resistance in breast cancer.

Disruption of circadian time structure and suppression of circadian nocturnal melatonin (MLT) production by exposure to dim light at night (dLAN), as occurs with night shift work and/or disturbed sleep-wake cycles, is associated with a significantly increased risk of breast cancer and resistance to tamoxifen and doxorubicin. Melatonin inhibition of human breast cancer chemoresistance involves mechanisms including suppression of tumor metabolism and inhibition of kinases and transcription factors which are often activated in drug-resistant breast cancer. Signal transducer and activator of transcription 3 (STAT3), frequently overexpressed and activated in paclitaxel (PTX)-resistant breast cancer, promotes the expression of DNA methyltransferase one (DNMT1) to epigenetically suppress the transcription of tumor suppressor Aplasia Ras homolog one (ARHI) which can sequester STAT3 in the cytoplasm to block PTX resistance. We demonstrate that breast tumor xenografts in rats exposed to dLAN and circadian MLT disrupted express elevated levels of phosphorylated and acetylated STAT3, increased DNMT1, but reduced sirtuin 1 (SIRT1) and ARHI. Furthermore, MLT and/or SIRT1 administration blocked/reversed interleukin 6 (IL-6)-induced acetylation of STAT3 and its methylation of ARH1 to increase ARH1 mRNA expression in MCF-7 breast cancer cells. Finally, analyses of the I-SPY 1 trial demonstrate that elevated MT1 receptor expression is significantly correlated with pathologic complete response following neo-adjuvant therapy in breast cancer patients. This is the first study to demonstrate circadian disruption of MLT by dLAN driving intrinsic resistance to PTX via epigenetic mechanisms increasing STAT3 expression and that MLT administration can reestablish sensitivity of breast tumors to PTX and drive tumor regression.

Effect of Daytime Blue-enriched LED Light on the Nighttime Circadian Melatonin Inhibition of Hepatoma 7288CTC Warburg Effect and Progression.

Liver cancer is the second leading cause of cancer death worldwide. Metabolic pathways within the liver and liver cancers are highly regulated by the central circadian clock in the suprachiasmatic nuclei (SCN). Daily light and dark cycles regulate the SCN-driven pineal production of the circadian anticancer hormone melatonin and temporally coordinate circadian rhythms of metabolism and physiology in mammals. In previous studies, we demonstrated that melatonin suppresses linoleic acid metabolism and the Warburg effect (aerobic glycolysis)in human breast cancer xenografts and that blue-enriched light (465-485 nm) from light-emitting diode lighting at daytime (bLAD) amplifies nighttime circadian melatonin levels in rats by 7-fold over cool white fluorescent (CWF) lighting. Here we tested the hypothesis that daytime exposure of tissue-isolated Morris hepatoma 7288CTC-bearing male rats to bLAD amplifies the nighttime melatonin signal to enhance the inhibition of tumor growth. Compared with rats housed under a 12:12-h light:dark cycle in CWF light, rats in bLAD light evinced a 7-fold higher peak plasma melatonin level at the mid-dark phase; in addition, high melatonin levels were prolonged until 4 h into the light phase. After implantation of tissue-isolated hepatoma 7288CTC xenografts, tumor growth rates were markedly delayed, and tumor cAMP levels, LA metabolism, the Warburg effect, and growth signaling activities were decreased in rats in bLAD compared with CWF daytime lighting. These data show that the increased nighttime circadian melatonin levels due to bLAD exposure decreases hepatoma metabolic, signaling, and proliferative activities beyond what occurs after normal melatonin signaling under CWF light.

A1AR-mediated renal protection against ischemia/reperfusion injury is dependent on HSP27 induction.

PURPOSE: A1 adenosine receptor (AR) activation has been demonstrated to attenuate renal ischemia/reperfusion injury (IRI), but the exact mechanism of this protection remains to be well elucidated. METHODS: Male C57BL/6 mice were used in the present study. Expression of heat shock protein (HSP) 27 and HSF-1 were detected using western blot analysis. An RNA interference with adenovirus vector using short hairpin RNA targeting HSP27 was developed. Together with renal IRI model, indicators of renal function, acute tubular necrosis, inflammation and apoptosis were measured in kidneys after 24-h reperfusion. RESULTS: We found activation of A1AR stimulated induction of HSP27 and its major transcriptional factor HSF-1. It was observed that renal inhibition of HSP27 abolished the renoprotective effects afforded by A1AR activation indicated by worse renal function, severer acute tubular necrosis and pro-inflammatory reaction. In addition, HSP27 induction by A1AR activation protects the kidney from IRI via suppressing cell apoptosis, proved by decreased caspase-3 activation and DNA fragmentation, which was also removed by inhibition of HSP27. CONCLUSIONS: Activation of A1AR produces renoprotective effects via HSP27 induction. It suggests that preconditional HSP27 activation might have a great potential for the treatment of renal IRI.

Lipopolysaccharide-Binding Protein Downregulates Fractalkine through Activation of p38 MAPK and NF-κB.

BACKGROUND: LBP and fractalkine are known to be involved in the pathogenesis of ARDS. This study investigated the relationship between LBP and fractalkine in LPS-induced A549 cells and rat lung tissue in an ARDS rat model. METHODS: A549 cells were transfected with LBP or LBP shRNA plasmid DNA or pretreated with SB203580 or SC-514 following LPS treatment. An ARDS rat model was established using LPS with or without LBPK95A, SB203580, or SC-514 treatment. RT-PCR, western blotting, ELISA, immunofluorescence, coimmunoprecipitation, and immunohistochemical staining were used to study the expression of fractalkine and LBP and p38 MAPK and p65 NF-κB activities. RESULTS: LPS increased LBP and reduced fractalkine. LBP overexpression further decreased LPS-induced downregulation of fractalkine and p38 MAPK and p65 NF-κB activation; LBP gene silencing, SB203580, and SC-514 suppressed LPS-induced downregulation of fractalkine and p38 MAPK and p65 NF-κB activation in A549 cells. LBP and fractalkine in lung tissue were increased and decreased, respectively, following LPS injection. LBPK95A, SB203580, and SC-514 ameliorated LPS-induced rat lung injury and suppressed LPS-induced downregulation of fractalkine by decreasing phospho-p38 MAPK and p65 NF-κB. CONCLUSIONS: The results indicate that LBP downregulates fractalkine expression in LPS-induced A549 cells and in an ARDS rat model through activation of p38 MAPK and NF-κB.

Graphene nanoplatelets induced heterogeneous bimodal structural magnesium matrix composites with enhanced mechanical properties.

In this work, graphene nanoplatelets (GNPs) reinforced magnesium (Mg) matrix composites were synthesised using the multi-step dispersion route. Well-dispersed but inhomogeneously distributed GNPs were obtained in the matrix. Compared with the monolithic alloy, the nanocomposites exhibited dramatically enhanced Young's modulus, yield strength and ultimate tensile strength and relatively high plasticity, which mainly attributed to the significant heterogeneous laminated microstructure induced by the addition of GNPs. With increasing of the concentration of GNPs, mechanical properties of the composites were gradually improved. Especially, the strengthening efficiency of all the composites exceeded 100%, which was significantly higher than that of carbon nanotubes reinforced Mg matrix composites. The grain refinement and load transfer provided by the two-dimensional and wrinkled surface structure of GNPs were the dominated strengthening mechanisms of the composites. This investigation develops a new method for incorporating GNPs in metals for fabricating high-performance composites.

Nur77 attenuates endothelin-1 expression via downregulation of NF-κB and p38 MAPK in A549 cells and in an ARDS rat model.

Acute respiratory distress syndrome (ARDS) is characterized by inflammatory injury to the alveolar and capillary barriers that results in impaired gas exchange and severe acute respiratory failure. Nuclear orphan receptor Nur77 has emerged as a regulator of gene expression in inflammation, and its role in the pathogenesis of ARDS is not clear. The objective of this study is to investigate the potential role of Nur77 and its underlying mechanism in the regulation of endothelin-1 (ET-1) expression in lipopolysaccharide (LPS)-induced A549 cells and an ARDS rat model. We demonstrate that LPS induced Nur77 expression and nuclear export in A549 cells. Overexpression of Nur77 markedly decreased basal and LPS-induced ET-1 expression in A549 cells, whereas knockdown of Nur77 increased the ET-1 expression. LPS-induced phosphorylation and nuclear translocation of NF-κB and p38 MAPK were blocked by Nur77 overexpression and augmented by Nur77 knockdown in A549 cells. In vivo, LPS induced Nur77 expression in lung in ARDS rats. Pharmacological activation of Nur77 by cytosporone B (CsnB) inhibited ET-1 expression in ARDS rats, decreased LPS-induced phosphorylation of NF-κB and p38 MAPK, and relieved lung, liver, and kidney injury. Pharmacological deactivation of Nur77 by 1,1-bis-(3'-indolyl)-1-(p-hydroxyphenyl)methane (DIM-C-pPhOH, C-DIM8) had no effect on ET-1 expression and lung injury. These results indicated that Nur77 decreases ET-1 expression by suppressing NF-κB and p38 MAPK in LPS-stimulated A549 cells in vitro, and, in an LPS-induced ARDS rat model, CsnB reduced ET-1 expression and lung injury in ARDS rats.

Melatonin Represses Metastasis in Her2-Postive Human Breast Cancer Cells by Suppressing RSK2 Expression.

The importance of the circadian/melatonin signal in suppressing the metastatic progression of breast and other cancers has been reported by numerous laboratories including our own. Currently, the mechanisms underlying the antimetastatic actions of melatonin have not been well established. In the present study, the antimetastatic actions of melatonin were evaluated and compared on the ERα-negative, Her2-positive SKBR-3 breast tumor cell line and ERα-positive MCF-7 cells overexpressing a constitutively active HER2.1 construct (MCF-7Her2.1 cells). Activation of Her2 is reported to induce the expression and/or phosphorylation-dependent activation of numerous kinases and transcription factors that drive drug resistance and metastasis in breast cancer. A key signaling node activated by the Her2/Mapk/Erk pathway is Rsk2, which has been shown to induce numerous signaling pathways associated with the development of epithelial-to-mesenchymal transition (EMT) and metastasis including: Creb, Stat3, cSrc, Fak, Pax, Fascin, and actin polymerization. The data demonstrate that melatonin (both endogenous and exogenous) significantly represses this invasive/metastatic phenotype through a mechanism that involves the suppression of EMT, either by promoting mesenchymal-to-epithelial transition, and/or by inhibiting key signaling pathways involved in later stages of metastasis. These data, combined with our earlier in vitro studies, support the concept that maintenance of elevated and extended duration of nocturnal melatonin levels plays a critical role in repressing the metastatic progression of breast cancer. IMPLICATIONS: Melatonin inhibition of Rsk2 represses the metastatic phenotype in breast cancer cells suppressing EMT or inhibiting other mechanisms that promote metastasis; disruption of the melatonin signal may promote metastatic progression in breast cancer. Mol Cancer Res; 14(11); 1159-69. ©2016 AACR.

Transforming growth factor beta 1 induced endothelin-1 release is peroxisome proliferator-activated receptor gamma dependent in A549 cells.

BACKGROUND: Endothelin-1 (ET-1) is involved in pulmonary vascular remodeling. The aim of this study was to investigate the biochemical interactions between PPAR-γ, TGF-ß1 and ET-1 in vitro. METHODS: A549 cells were pre-treated with S2505 (10 µM), S2871 (10 µM) with/without SB203580 (10 µM) for 60 min following 2 h treatment with 10 ng/mL TGF-ß1. A549 cells were also transfected with positive or negative PPAR-γ plasmids for comparison. RT-PCR, ELISA, western blotting and confocal laser scanning microscopy (CLSM) were used to measure the relevant expression of mRNA, protein, mediators of pathways and nuclear factor translocation. RESULTS: SB203580 inhibited TGF-ß1 induced ET-1 expression in A549 cells. S2871 decreased PPAR-γ mRNA and increase TGF-ß1-induced ET-1 expression. S2871 increased phosphorylation of p38 MAPK and Smad2. Cells transfected with PPAR-γ negative plasmid increased TGF-ß1 induced ET-1 expression, and increased the expression of phospho-p38 MAPK and phospho-Smad2. S2505 increased PPAR-γ mRNA expression, suppressed the increased TGF-ß1-induced expression of ET-1. S2505 inhibited TGF-ß1 induced phosphorylation of p38 MAPK and Smad2, also the nuclear translocation of Smad2. Cells transfected with PPAR-γ positive plasmid reduced TGF-ß1-induced ET-1 expression, and inhibited the expression of phospho-p38 MAPK and phospho-Smad2. CONCLUSIONS: TGF-ß1 induced release of endothelin-1 is PPAR-γ dependent in cultured A549 cells.

Melatonin suppression of aerobic glycolysis (Warburg effect), survival signalling and metastasis in human leiomyosarcoma.

Leiomyosarcoma (LMS) represents a highly malignant, rare soft tissue sarcoma with high rates of morbidity and mortality. Previously, we demonstrated that tissue-isolated human LMS xenografts perfused in situ are highly sensitive to the direct anticancer effects of physiological nocturnal blood levels of melatonin which inhibited tumour cell proliferative activity, linoleic acid (LA) uptake and metabolism to 13-hydroxyoctadecadienoic acid (13-HODE). Here, we show the effects of low pharmacological blood concentrations of melatonin following oral ingestion of a melatonin supplement by healthy adult human female subjects on tumour proliferative activity, aerobic glycolysis (Warburg effect) and LA metabolic signalling in tissue-isolated LMS xenografts perfused in situ with this blood. Melatonin markedly suppressed aerobic glycolysis and induced a complete inhibition of tumour LA uptake, 13-HODE release, as well as significant reductions in tumour cAMP levels, DNA content and [(3) H]-thymidine incorporation into DNA. Furthermore, melatonin completely suppressed the phospho-activation of ERK 1/2, AKT, GSK3ß and NF-kB (p65). The addition of S20928, a nonselective melatonin antagonist, reversed these melatonin inhibitory effects. Moreover, in in vitro cell culture studies, physiological concentrations of melatonin repressed cell proliferation and cell invasion. These results demonstrate that nocturnal melatonin directly inhibited tumour growth and invasion of human LMS via suppression of the Warburg effect, LA uptake and other related signalling mechanisms. An understanding of these novel signalling pathway(s) and their association with aerobic glycolysis and LA metabolism in human LMS may lead to new circadian-based therapies for the prevention and treatment of LMS and potentially other mesenchymally derived solid tumours.

Daytime Blue Light Enhances the Nighttime Circadian Melatonin Inhibition of Human Prostate Cancer Growth.

Light controls pineal melatonin production and temporally coordinates circadian rhythms of metabolism and physiology in normal and neoplastic tissues. We previously showed that peak circulating nocturnal melatonin levels were 7-fold higher after daytime spectral transmittance of white light through blue-tinted (compared with clear) rodent cages. Here, we tested the hypothesis that daytime blue-light amplification of nocturnal melatonin enhances the inhibition of metabolism, signaling activity, and growth of prostate cancer xenografts. Compared with male nude rats housed in clear cages under a 12:12-h light:dark cycle, rats in blue-tinted cages (with increased transmittance of 462-484 nm and decreased red light greater than 640 nm) evinced over 6-fold higher peak plasma melatonin levels at middark phase (time, 2400), whereas midlight-phase levels (1200) were low (less than 3 pg/mL) in both groups. Circadian rhythms of arterial plasma levels of linoleic acid, glucose, lactic acid, pO2, pCO2, insulin, leptin, and corticosterone were disrupted in rats in blue cages as compared with the corresponding entrained rhythms in clear-caged rats. After implantation with tissue-isolated PC3 human prostate cancer xenografts, tumor latency-to-onset of growth and growth rates were markedly delayed, and tumor cAMP levels, uptake-metabolism of linoleic acid, aerobic glycolysis (Warburg effect), and growth signaling activities were reduced in rats in blue compared with clear cages. These data show that the amplification of nighttime melatonin levels by exposing nude rats to blue light during the daytime significantly reduces human prostate cancer metabolic, signaling, and proliferative activities.

Melatonin: an inhibitor of breast cancer.

The present review discusses recent work on melatonin-mediated circadian regulation, the metabolic and molecular signaling mechanisms that are involved in human breast cancer growth, and the associated consequences of circadian disruption by exposure to light at night (LEN). The anti-cancer actions of the circadian melatonin signal in human breast cancer cell lines and xenografts heavily involve MT1 receptor-mediated mechanisms. In estrogen receptor alpha (ERα)-positive human breast cancer, melatonin suppresses ERα mRNA expression and ERα transcriptional activity via the MT1 receptor. Melatonin also regulates the transactivation of other members of the nuclear receptor superfamily, estrogen-metabolizing enzymes, and the expression of core clock and clock-related genes. Furthermore, melatonin also suppresses tumor aerobic metabolism (the Warburg effect) and, subsequently, cell-signaling pathways critical to cell proliferation, cell survival, metastasis, and drug resistance. Melatonin demonstrates both cytostatic and cytotoxic activity in breast cancer cells that appears to be cell type-specific. Melatonin also possesses anti-invasive/anti-metastatic actions that involve multiple pathways, including inhibition of p38 MAPK and repression of epithelial-mesenchymal transition (EMT). Studies have demonstrated that melatonin promotes genomic stability by inhibiting the expression of LINE-1 retrotransposons. Finally, research in animal and human models has indicated that LEN-induced disruption of the circadian nocturnal melatonin signal promotes the growth, metabolism, and signaling of human breast cancer and drives breast tumors to endocrine and chemotherapeutic resistance. These data provide the strongest understanding and support of the mechanisms that underpin the epidemiologic demonstration of elevated breast cancer risk in night-shift workers and other individuals who are increasingly exposed to LEN.

Doxorubicin resistance in breast cancer is driven by light at night-induced disruption of the circadian melatonin signal.

Chemotherapeutic resistance, particularly to doxorubicin (Dox), represents a major impediment to successfully treating breast cancer and is linked to elevated tumor metabolism and tumor over-expression and/or activation of various families of receptor- and non-receptor-associated tyrosine kinases. Disruption of circadian time structure and suppression of nocturnal melatonin production by dim light exposure at night (dLEN), as occurs with shift work, and/or disturbed sleep-wake cycles, is associated with a significantly increased risk of an array of diseases, including breast cancer. Melatonin inhibits human breast cancer growth via mechanisms that include the suppression of tumor metabolism and inhibition of expression or phospho-activation of the receptor kinases AKT and ERK1/2 and various other kinases and transcription factors. We demonstrate in tissue-isolated estrogen receptor alpha-positive (ERα+) MCF-7 human breast cancer xenografts, grown in nude rats maintained on a light/dark cycle of LD 12:12 in which dLEN is present during the dark phase (suppressed endogenous nocturnal melatonin), a significant shortening of tumor latency-to-onset, increased tumor metabolism and growth, and complete intrinsic resistance to Dox therapy. Conversely, a LD 12:12 dLEN environment incorporating nocturnal melatonin replacement resulted in significantly lengthened tumor latency-to-onset, tumor regression, suppression of nighttime tumor metabolism, and kinase and transcription factor phosphorylation, while Dox sensitivity was completely restored. Melatonin acts as both a tumor metabolic inhibitor and circadian-regulated kinase inhibitor to reestablish the sensitivity of breast tumors to Dox and drive tumor regression, indicating that dLEN-induced circadian disruption of nocturnal melatonin production contributes to a complete loss of tumor sensitivity to Dox chemotherapy.