ASIC1/RIP1 accelerates atherosclerosis via disrupting lipophagy.

INTRODUCTION: Atherosclerosis, a major contributor to cardiovascular disease, remains a significant health concern worldwide. While previous research has shown that acid-sensing ion channel 1 (ASIC1) impedes macrophage cholesterol efflux, its precise role in atherogenesis and the underlying mechanisms have remained elusive. OBJECTIVES: This study aimed to investigate the role of ASIC1 in atherosclerosis and its underlying mechanisms. METHODS: First, data from a single-cell RNA sequencing (scRNA-seq) database were used to explore the relationships between ASIC1 differential expression and lipophagy in human atherosclerotic lesions. Finally, we validated the role of ASIC1/RIP1 signaling in lipophagy in vivo (human and mice) and in vitro (RAW264.7 and HTP-1 cells). RESULT: Our results demonstrated a significant increase in ASIC1 protein levels within CD68+ macrophages in both human aortic lesions and AopE-/- mouse lesion areas compared to nonlesion regions. Concurrently, there was a notable decrease in lipophagy, a crucial process for lipid metabolism. In vitro assays further elucidated that ASIC1 interaction with RIP1 (receptor-interacting protein 1) promoted the phosphorylation of RIP1 at serine 166 and transcription factor EB (TFEB) at serine 142, leading to disrupted lipophagy and increased lipid accumulation. Intriguingly, all these events were reversed upon ASIC1 deficiency and RIP1 inhibition. Furthermore, in ApoE-/- mouse models of atherosclerosis, silencing ASIC1 expression or inhibiting RIP1 activation not only significantly attenuated atherogenesis but also restored TFEB-mediated lipophagy in aortic tissues. This was evidenced by reduced TFEB Ser-142 phosphorylation, decreased LC3II and LAMP1 protein expression, increased numbers of lipophagosomes, and a decrease in lipid droplets. CONCLUSION: Our findings unveil the critical role of macrophage ASIC1 in interacting with RIP1 to inhibit lipophagy, thereby promoting atherogenesis. Targeting ASIC1 represents a promising therapeutic avenue for the treatment of atherosclerosis.

Research on the Spatial Structure of the European Union's Tourism Economy and Its Effects.

With the implementation of European integration policies such as the single market, the Euro and the Schengen Visa, the EU member states are developing closer economic ties through tourism, and their level of tourism integration is constantly improving. Taking the 28 EU member states as research objects, this paper constructs a tourism economic connection network among them, measures the strength of their tourism economic connections from 1995 to 2018 by using the modified gravity model and social network method, and analyzes the spatial structure characteristics and effects of the EU tourism economy. The results are as follows: (1) The tourism economic ties of EU member states are growing increasingly close, enhancing network stability. (2) Germany, France, Italy, Austria and the United Kingdom are the top five countries in the degree centrality and closeness centrality rankings, meaning that they are located in the center of the network and have great influence, and the network is becoming increasingly concentrated. Germany, Italy, Sweden, Austria and France play an important intermediary role in the network, and the centrality of most member states has increased. (3) The core areas are mainly concentrated in Western Europe, Southern Europe, Mediterranean mainland countries and Central Europe, while the marginal areas are mainly concentrated in Eastern Europe, Northern Europe and Mediterranean island countries; the network connection density of the core area, the network connection density of the marginal area, and the network connection density between the core and marginal area overall show an increasing trend. (4) Improvements in the complete network connectedness and a reduction in graph efficiency can significantly reduce differences in EU tourism economic development levels and improve spatial equity.

An enzymatic on/off switch-mediated assay for KRAS hotspot point mutation detection of circulating tumor DNA.

BACKGROUND: To detect the mutations of KRAS gene in colorectal cancer patients and other cancer patients, it is of value to develop non-invasive, sensitive, specific, easy, and low-cost assays. METHODS: Templates harboring hotspot mutations of the KRAS gene were constructed, and primers were designed for evaluation of the specificity, and sensitivity of detection system consisted of exonuclease polymerase-mediated on/off switch; then, gel electrophoresis and real-time PCR were performed for verification. The assay was verified by testing the DNA pool of normal controls and circulating DNA (ctDNA) samples from 14 tumor patients, as compared to Sanger sequencing. RESULTS: A specific and sensitive assay consisted of exonuclease polymerase-mediated on/off switch, and multiplex real-time PCR method has been established. This assay could detect <100 copies of KRAS mutation in more than 10 million copies of wild-type KRAS gene fragments. This assay was applied to test KRAS gene mutations in three cases of fourteen ctDNA samples, and the results were consistent with Sanger sequencing. However, this PCR-based assay was more sensitive and easier to be interpreted. CONCLUSION: This assay can detect the presence of KRAS hotspot mutations in clinical circulating tumor DNA samples. The assay has a potential to be used in early diagnosis of colorectal cancer as well as other types of cancer.

Acid-sensing ion channels: Linking extracellular acidification with atherosclerosis.

Extracellular acidification in atherosclerosis-prone regions of arterial walls is considered pro-atherosclerotic by exerting detrimental effect on macrophages, endothelial cells (ECs) and vascular smooth muscle cells (VSMCs). Acid-sensing ion channels (ASICs), a family of extracellular H+ (proton)-gated cation channels, are present extensively in the nervous system and other tissues, implying physiologic as well as pathophysiologic importance. Aberrant activation of ASICs is thought to be associated in EC dysfunction, macrophage phenotypic switch, and VSMC migration and proliferation. Although in vitro evidence acknowledges the contribution of ASIC activation in atherosclerosis, no direct evidence confirms their pro-atherosclerotic roles in vivo. In this review, the effect of extracellular acidity on three major contributors, ECs, macrophages, and VSMCs, is discussed focusing on the potential roles of ASICs in atherosclerotic development and underlying pathology. A more comprehensive understanding of ASICs in these processes may provide promising new therapeutic targets for treatment and prevention of atherosclerotic diseases.

Application of Differentially Methylated Loci in Clinical Diagnosis of Trisomy 21 Syndrome.

AIMS: To determine the diagnostic precision of using different sets of fetal-specific methylation markers with methylation-sensitive restriction enzyme-quantitative polymerase chain reaction (MSRE-qPCR) for detection of trisomy 21 (T21). MATERIALS AND METHODS: The diagnostic value for trisomy 21 of differential methylation of HLCS, C21orf25, and RASSF1A (a fetal-specific internal control) was examined by MSRE-qPCR. RESULTS: The combined marker set of HLCS and RASSF1A achieved accurate quantification of fetal-specific chromosome 21 and was an excellent marker for detecting the presence of three copies of chromosome 21. MSRE-qPCR correctly identified three cases of fetal T21 from 11 clinical samples, which were 100% consistent with karyotyping results. In addition, this method was able to detect fetal-specific, T21-derived, cell-free fetal DNA at concentrations as low as 0.1%. CONCLUSIONS: Evaluation of the HLCS and RASSF1A fetal-specific methylation marker set by MSRE-qPCR could be a highly sensitive, specific, cost-effective, and noninvasive prenatal screening method for T21. This MSRE-qPCR testable marker should be considered as an alternative to next generation sequencing technology for diagnosing fetal T21.

Lipid metabolism and carcinogenesis, cancer development.

The disorder of lipid metabolism is pathologically linked to hyperlipidemia, lipid storage disease, obesity and other related diseases. Intriguingly, recent studies have revealed that lipid metabolism disorders play an important role in carcinogenesis and development as well, since they cause abnormal expression of various genes, proteins, and dysregulation of cytokines and signaling pathways. More importantly, lipid-lowering drugs and anti-lipid per-oxidation treatment have been showing their advantages in clinic, in comparison with other anti-cancer drugs with high toxicity. Thus, further elucidation of molecular mechanism between lipid metabolism and cancer is essential in developing novel diagnostic biomarkers and therapeutic targets of human cancers.

A Novel Assay Coupling Dephosphorylation and Blue/White Colony Screening for the G > A Hotspot Mutation at Codon 13 of KRAS Gene.

Development of sensitive assay for detection of hotspot mutations of cancer driving gene is crucial for circulating tumor DNA analysis. This study tested the possibilities of applying restriction enzyme digestion and dephosphorylation coupled with blue/white screening technology for analyzing a hotspot point mutation in codon 13 of KRAS gene. The present study has documented that the combination of PCR with restriction digestion, dephosphorylation, blue/white screening and Sanger's sequencing can identify rare mutations with sensitivities at 0.003%. This novel assay with high sensitivity may have application in the diagnosis of early cancer targeting ctDNAs.

CLCA2 is a positive regulator of store-operated calcium entry and TMEM16A.

The Chloride Channel Accessory (CLCA) protein family was first characterized as regulators of calcium-activated chloride channel (CaCC) currents (ICaCC), but the mechanism has not been fully established. We hypothesized that CLCAs might regulate ICaCC by modulating intracellular calcium levels. In cells stably expressing human CLCA2 or vector, we found by calcium imaging that CLCA2 moderately enhanced intracellular-store release but dramatically increased store-operated entry of calcium upon cytosolic depletion. Moreover, another family member, CLCA1, produced similar effects on intracellular calcium mobilization. Co-immunoprecipitation revealed that CLCA2 interacted with the plasma membrane store-operated calcium channel ORAI-1 and the ER calcium sensor STIM-1. The effect of CLCA2 on ICaCC was tested in HEK293 stably expressing calcium-activated chloride channel TMEM16A. Co-expression of CLCA2 nearly doubled ICaCC in response to a calcium ionophore. These results unveil a new mechanism by which CLCA family members activate ICaCC and suggest a broader role in calcium-dependent processes.

Advances in the Engineering of the Gene Editing Enzymes and the Genomes: Understanding and Handling the Off-Target Effects of CRISPR/Cas9.

In the past decades, significant progresses have been achieved in genetic engineering of nucleases. Among the genetically engineered nucleases, zinc finger nucleases, transcription activator-like (TAL) effector nucleases, and CRIPSPR/Cas9 system form a new field of gene editing. The gene editing efficiency or targeting effect and the off-target effect are the two major determinant factors in evaluating the usefulness of a new enzyme. Engineering strategies in improving these gene editing enzymes, particularly in minimizing their off-target effects, are the focus of this paper. Examples of using these genetically engineered enzymes in genome modification are discussed in order to better understand the requirement of engineering efforts in obtaining more powerful and useful gene editing enzymes. In addition, the identification of naturally existed anti-Cas proteins has been employed in minimizing off-target effects. Considering the future application in human gene therapy, optimization of these well recognized gene editing enzymes and exploration of more novel enzymes are both required. Before people find an ideal gene editing system having virtually no off-target effect, technologies used to screen and identify off-target effects are of importance in clinical trials employing gene therapy.

Serum miR-20a is a promising biomarker for gastric cancer.

Gastric cancer (GC) is a common type of cancer, particularly in China. Numerous studies have demonstrated that circulating microRNAs (miRNAs) have potential applications as noninvasive biomarkers for cancer diagnosis and prognosis. Microarray-based serum miRNA profiling was performed on the serum of 12 paired pre- and post-operative GC patients to screen differentially expressed serum miRNAs. Twelve different serum miRNAs between pre- and post-operative GC patients were identified. Those miRNAs were verified by real-time quantitative polymerase chain reaction in 110 paired pre- and post-operative serum samples from 55 GC patients. miR-20a was confirmed and demonstrated potential as a GC-associated biomarker. Furthermore, the levels of serum miR-20a were significantly different between GC, nasopharyngeal cancer, colorectal carcinoma, breast cancer and non-cancerous controls. In addition, it was found that serum miR-20a levels correlated with age, tumor stage, differentiated degree and lymph node metastasis in GC. Survival analysis indicated that GC patients with elevated levels of serum miR-20a had poor survival. Thus, serum miR-20a may serve as a molecular marker for diagnosis, evaluating therapeutic efficacy and prognosis, as well as monitoring recurrence in GC patients.

Identification of the C-terminal domain of Daxx acts as a potential regulator of intracellular cholesterol synthesis in HepG2 cells.

Daxx is a highly conserved nuclear transcriptional factor, which has been implicated in many nuclear processes including transcription and cell cycle regulation. Our previous study demonstrated Daxx also plays a role in regulation of intracellular cholesterol content. Daxx contains several domains that are essential for interaction with a growing number of proteins. To delineate the underlying mechanism of hypocholesterolemic activity of Daxx, we constructed a set of plasmids which can be used to overexpress different fragments of Daxx and transfected to HepG2 cells. We found that the C- terminal region Daxx626-740 clearly reduced intracellular cholesterol levels and inhibited the expression of SREBPs and SCAP. In GST pull-down experiments and Double immunofluorescence assays, Daxx626-740 was demonstrated to bind directly to androgen receptor (AR). Our findings suggest that the interaction of Daxx626-740 and AR abolishes the AR-mediated activation of SCAP/SREBPs pathway, which suppresses the de novo cholesterol synthesis. Thus, C-terminal domain of Daxx acts as a potential regulator of intracellular cholesterol content in HepG2 cells.

Heterogeneous nuclear ribonucleoprotein K is overexpressed and associated with poor prognosis in gastric cancer.

Heterogeneous nuclear ribonucleoprotein K (hnRNP K) is one of the major pre-mRNA-binding proteins, that is involved in translational modifications. In our previous studies, we found that hnRNP K is associated with human gastric cancer. The protein levels of hnRNP K were detected in cell lines and tissue microarrays. The correlation between hnRNP K expression and patient survival rate was evaluated by Kaplan-Meier survival analysis. In addition, we also detected hnRNP K expression in preoperative and postoperative serum samples from patients with gastric cancer, and serum samples from healthy volunteers. We found that hnRNP K was overexpressed in the gastric cancer cell lines. The levels of hnRNP K were significantly elevated in the gastric cancer tissues compared with that noted in the tumor-adjacent gastric mucosal and normal gastric mucosal sampes, and hnRNP K expression was found to correlate with tumor stage and lymph node metastasis. However, the level of serum hnRNP K did not differ significantly between gastric cancer patients and healthy volunteers. We also found that patients whose tumors showed elevated expression of hnRNP K had poor survival. The present study suggests that hnRNP K is a promising tissue biomarker for diagnosing gastric cancer and is a prognostic indicator for patients with gastric cancer.

CLCA2 Interactor EVA1 Is Required for Mammary Epithelial Cell Differentiation.

CLCA2 is a p53-, p63-inducible transmembrane protein that is frequently downregulated in breast cancer. It is induced during differentiation of human mammary epithelial cells, and its knockdown causes epithelial-to-mesenchymal transition (EMT). To determine how CLCA2 promotes epithelial differentiation, we searched for interactors using membrane dihybrid screening. We discovered a strong interaction with the cell junctional protein EVA1 (Epithelial V-like Antigen 1) and confirmed it by co-immunoprecipitation. Like CLCA2, EVA1 is a type I transmembrane protein that is regulated by p53 and p63. It is thought to mediate homophilic cell-cell adhesion in diverse epithelial tissues. We found that EVA1 is frequently downregulated in breast tumors and breast cancer cell lines, especially those of mesenchymal phenotype. Moreover, knockdown of EVA1 in immortalized human mammary epithelial cells (HMEC) caused EMT, implying that EVA1 is essential for epithelial differentiation. Both EVA1 and CLCA2 co-localized with E-cadherin at cell-cell junctions. The interacting domains were delimited by deletion analysis, revealing the site of interaction to be the transmembrane segment (TMS). The primary sequence of the CLCA2 TMS was found to be conserved in CLCA2 orthologs throughout mammals, suggesting that its interaction with EVA1 co-evolved with the mammary gland. A screen for other junctional interactors revealed that CLCA2 was involved in two different complexes, one with EVA1 and ZO-1, the other with beta catenin. Overexpression of CLCA2 caused downregulation of beta catenin and beta catenin-activated genes. Thus, CLCA2 links a junctional adhesion molecule to cytosolic signaling proteins that modulate proliferation and differentiation. These results may explain how attenuation of CLCA2 causes EMT and why CLCA2 and EVA1 are frequently downregulated in metastatic breast cancer cell lines.

Convection-enhanced delivery of sorafenib and suppression of tumor progression in a murine model of brain melanoma through the inhibition of signal transducer and activator of transcription 3.

OBJECT Despite recent advances, metastatic melanoma remains a terminal disease, in which life-threatening brain metastasis occurs in approximately half of patients. Sorafenib is a multikinase inhibitor that induces apoptosis of melanoma cells in vitro. However, systemic administration has been ineffective because adequate tissue concentrations cannot be achieved. This study investigated if convection-enhanced delivery (CED) of sorafenib would enhance tumor control and survival via inhibition of the signal transducer and activator of transcription 3 (Stat3) pathway in a murine model of metastatic brain melanoma. METHODS Melanoma cells treated with sorafenib in vitro were examined for signaling and survival changes. The effect of sorafenib given by CED was assessed by bioluminescent imaging and animal survival. RESULTS The results showed that sorafenib induced cell death in the 4 established melanoma cell lines and in 1 primary cultured melanoma cell line. Sorafenib inhibited Stat3 phosphorylation in HTB65, WYC1, and B16 cells. Accordingly, sorafenib treatment also decreased expression of Mcl-1 mRNA in melanoma cell lines. Because sorafenib targets multiple pathways, the present study demonstrated the contribution of the Stat3 pathway by showing that mouse embryonic fibroblast (MEF) Stat3 +/+ cells were significantly more sensitive to sorafenib than MEF Stat3 -/- cells. In the murine model of melanoma brain metastasis used in this study, CED of sorafenib increased survival by 150% in the treatment group compared with animals receiving the vehicle control (p < 0.01). CED of sorafenib also significantly abrogated tumor growth. CONCLUSIONS The data from this study indicate that local delivery of sorafenib effectively controls brain melanoma. These findings validate further investigation of the use of CED to distribute molecularly targeted agents.

Tissue vulnerability is increased following repetitive mild traumatic brain injury in the rat.

Repetitive mild traumatic brain injury (rmTBI) is an important medical concern for active sports and military personnel. Multiple mild injuries may exacerbate tissue damage resulting in cumulative brain injury and poor functional recovery. In the present study, we investigated the time course of brain vulnerability to rmTBI in a rat model of mild cortical controlled impact. An initial mild injury was followed by a second injury unilaterally at an interval of 1, 3, or 7 days. RmTBI animals were compared to single mTBI and sham treated animals. Neuropathology was assessed using multi-modal magnetic resonance imaging (MRI), followed by ex vivo tissue immunohistochemistry. Neurological and behavioral outcomes were evaluated in a subset of animals receiving rmTBI 3 days apart and shams. RmTBI 1 or 3 days apart but not 7 days apart revealed significantly exacerbated MRI-definable lesion volumes compared to single mTBI and shams. Increases in cortical tissue damage, extravascular iron and glial activation assessed by histology/immunohistochemistry correlated with in vivo MRI findings where shorter intervals (1 or 3 days apart) resulted in greater tissue pathology. There were no neurological deficits associated with rmTBI 3 day animals. At 1 mo post-injury, animals with rmTBI 3 days apart showed reduced exploratory behaviors and subtle spatial learning memory impairments were observed. Collectively, our findings suggest that the mildly-impacted brain is more vulnerable to repetitive injury when delivered within 3 days following initial mTBI.

FLJ10540 is associated with tumor progression in nasopharyngeal carcinomas and contributes to nasopharyngeal cell proliferation, and metastasis via osteopontin/CD44 pathway.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is well-known for its highly metastatic characteristics, but little is known of its molecular mechanisms. New biomarkers that predict clinical outcome, in particular the ability of the primary tumor to develop metastatic tumors are urgently needed. The aim of this study is to investigate the role of FLJ10540 in human NPC development. METHODS: A bioinformatics approach was used to explore the potentially important regulatory genes involved in the growth/metastasis control of NPC. FLJ10540 was chosen for this study. Two co-expression strategies from NPC microarray were employed to identify the relationship between FLJ10540 and osteopontin. Quantitative-RT-PCR, immunoblotting, and immunohistochemistry analysis were used to investigate the mRNA and protein expression profiles of FLJ10540 and osteopontin in the normal and NPC tissues to confirm microarray results. TW01 and Hone1 NPC cells with overexpression FLJ10540 or siRNA to repress endogenous FLJ10540 were generated by stable transfection to further elucidate the molecular mechanisms of FLJ10540-elicited cell growth and metastasis under osteopontin stimulation. RESULTS: We found that osteopontin expression exhibited a positive correlation with FLJ10540 in NPC microarray. We also demonstrated comprehensively that FLJ10540 and osteopontin were not only overexpressed in NPC specimens, but also significantly correlated with advanced tumor and lymph node-metastasis stages, and had a poor 5-year survival rate, respectively. Stimulation of NPC parental cells with osteopontin results in an increase in FLJ10540 mRNA and protein expressions. Functionally, FLJ10540 transfectant alone, or stimulated with osteopontin, exhibited fast growth and increased metastasis as compared to vehicle control with or without osteopontin stimulation. Conversely, knockdown of FLJ10540 by siRNA results in the suppression of NPC cell growth and motility. Treatment with anti-CD44 antibodies in NPC parental cells not only resulted in a decrease of FLJ10540 protein, but also affected the abilities of FLJ10540-elicited cell growth and motility in osteopontin stimulated-NPC cells. CONCLUSIONS: These findings suggest that FLJ10540 may be critical regulator of disease progression in NPC, and the underlying mechanism may involve in the osteopontin/CD44 pathway.

Fibulin-3 is associated with tumour progression and a poor prognosis in nasopharyngeal carcinomas and inhibits cell migration and invasion via suppressed AKT activity.

Nasopharyngeal carcinoma (NPC) is known for its highly metastatic character. Recent advances in diagnosis and treatment have not improved the high mortality rate that is attributable to early metastasis. Although several biomarkers correlate with metastasis and prognosis, the molecular mechanisms of NPC development and progression remain unclear. We demonstrate comprehensively that fibulin-3 is down-regulated in NPC. Loss of fibulin-3 expression is significantly correlated with advanced tumour and lymph node-metastasis stages, and indicates a poor 5-year survival rate. Functionally, fibulin-3 has the ability to suppress cell migration and invasion in NPC cancer cells by decreasing the activity of phospho-AKT. Conversely, its depletion by fibulin-3-mediated siRNAs may elevate phospho-AKT activity and significantly enhance the ability of NPC cancer cells to migrate and invade. Consistent with this negative association between fibulin-3 and phospho-AKT, their expression levels are inversely correlated in NPC specimens by immunohistochemical analysis. Thus, lower fibulin-3 expression is an important indicator of poor survival. It may also contribute to the development of new therapeutic strategies to block the PI3K/AKT pathway in NPC cancer cells.

A law of mutation: power decay of small insertions and small deletions associated with human diseases.

Indels in evolutionary studies are rapidly decayed obeying a power law. The present study analyzed the length distribution of small insertions and deletions associated with human diseases and confirmed that the decay pattern of these small mutations is similar to that of indels when the mutation datasets are large enough. The describable decay pattern of somatic mutations may have application in the evaluation of varied penetrance of different mutations and in association study of gene mutation with carcinogenesis.

Enhancement of esculetin on arsenic trioxide-provoked apoptosis in human leukemia U937 cells.

In order to overcome chemotherapy resistance, many laboratories are searching for agents that increase the sensitivity of cancer cells to anticancer drugs. Arsenic trioxide (As(2)O(3)) is widely used in treating human acute polymyelocytic leukemia (APL). However, solid tumors and other leukemia cells such as U937 promonocytic leukemia cells are insensitive to As(2)O(3). Esculetin, a coumarin derivative, has previously induced cell cycle arrest and apoptosis of HL-60 cells as well as enhanced taxol-induced apoptosis in HepG2 cells, thereby displaying anticancer potential. In this study, esculetin inhibited proliferation and mitogen activated protein kinases (MAPKs) activation in human leukemia U937 cells. Since inhibitors of MAPKs have modulated the GSH-redox state and enhanced the sensitivity of leukemia cells to As(2)O(3)-provoked apoptosis, we monitored the effect of combining esculetin and As(2)O(3) (2.5 microM) on the GSH level. Our study showed that esculetin, PD98059 (MEK/ERK inhibitor), and SP600125 (JNK inhibitor) similarly enhanced the As(2)O(3)-induced GSH depletion. We found that the As(2)O(3) (2.5 microM) treatment slightly induced apoptosis and the pretreatment of esculetin enhanced the As(2)O(3)-provoked apoptosis significantly. In addition, esculetin enhanced the effect of As(2)O(3) on caspase activation in U937 cells. We compared the combined esculetin and As(2)O(3) treatment to the As(2)O(3) treated alone. The combined esculetin and As(2)O(3) treatment increased Bid cleavage, Bax conformation change and cytochrome C release. The study also indicated that esculetin enhanced the As(2)O(3)-induced lysosomal leakage and apoptosis. Furthermore, pretreatment with N-acetylcysteine (NAC) reduced these enhanced effects. Based on these studies, esculetin enhances the As(2)O(3)-provoked apoptosis by modulating the MEK/ERK and JNK pathways and reducing intracellular GSH levels. GSH depletion led to higher oxidative stress which activated lysosomal-mitochondrial pathway of apoptosis.

Sniffing out cancer using the JPL electronic nose: a pilot study of a novel approach to detection and differentiation of brain cancer.

UNLABELLED: A proof-of-concept study was done to determine whether an electronic nose developed for air quality monitoring at the Jet Propulsion Laboratory (JPL) could be used to distinguish between the odors of organ and tumor tissues, with an eye to using such a device as one of several modes in multi-modal imaging and tumor differentiation during surgery. HYPOTHESIS: We hypothesized that the JPL electronic nose (ENose) would be able to distinguish between the odors of various organ and tumor tissues. MATERIALS AND METHODS: The odor signatures, or array response, of two organs, chicken heart and chicken liver, and cultured glioblastoma and melanoma tumor cell lines were recorded using the JPL Electronic Nose. The overall array responses were compared to determine whether they were sufficiently different to allow the organs and cell lines to be identified by their array responses. RESULTS: The ENose was able to distinguish between the two types of organ tissue and between the two types of tumor cell lines. The variation in array response for the organ tissues was 19% and between the two types of cultured cell lines was 22%. CONCLUSION: This study shows that it is possible to use an electronic nose to distinguish between two types of tumor cells and between two types of organ tissue. As we conducted the experiment with a sensor array built for air quality monitoring rather than for medical purposes, it may be possible to select an array that is optimized to distinguish between different types of cells and organ tissues. Further focused studies are needed to investigate the odor signatures of different cells as well as cellular proliferation, growth, differentiation and infiltration.