Decreased liver B vitamin-related enzymes as a metabolic hallmark of cancer cachexia

Cancer cachexia is a complex metabolic disorder accounting for ~20% of cancer-related deaths, yet its metabolic landscape remains unexplored. Here, we report a decrease in B vitamin-related liver enzymes as a hallmark of systemic metabolic changes occurring in cancer cachexia. Metabolomics of multiple mouse models highlights cachexia-associated reductions of niacin, vitamin B6, and a glycine-related subset of one-carbon (C1) metabolites in the liver. Integration of proteomics and metabolomics reveals that liver enzymes related to niacin, vitamin B6, and glycine-related C1 enzymes dependent on B vitamins decrease linearly with their associated metabolites, likely reflecting stoichiometric cofactor-enzyme interactions. The decrease of B vitamin-related enzymes is also found to depend on protein abundance and cofactor subtype. These metabolic/proteomic changes and decreased protein malonylation, another cachexia feature identified by protein post-translational modification analysis, are reflected in blood samples from mouse models and gastric cancer patients with cachexia, underscoring the clinical relevance of our findings.

Effect on Physical Functions of Older Adults When Refraining from Going out due to COVID-19 Restrictions

The study investigated the effect of refraining from going out during the coronavirus disease 2019 pandemic on physical function in community-dwelling older adults. The study included 49 patients who underwent home-visit rehabilitation. Four parameters of physical function—grip strength, five-times sit-to-stand test, single-leg stance test, and standing test for imbalance and disequilibrium (SIDE)—were assessed. They were evaluated before (March 2020) and after (May 2020) the state emergency was imposed, and the results were compared. The grip strength decreased significantly. A significant difference was also observed in the proportion of different SIDE levels in the study group before and after the implementation of the state emergency. The number of SIDE 2a or lower patients increased during the state emergency (p < 0.001). Comprehensive community support and rehabilitation are necessary to maintain physical function in older individuals. In particular, we believe that there is a need to utilize remote rehabilitation using digital devices (such as internet-based guidance) so that older adults can continue to exercise at home.

Fibronectin plays a major role in hypoxia-induced lenvatinib resistance in hepatocellular carcinoma PLC/PRF/5 cells

Resistance to lenvatinib mesylate (LEN), a systemic chemotherapy that can be administered orally, has been a major issue for treatment of hepatocellular carcinoma (HCC). Although HCC is the tumor that most exhibits intratumoral hypoxia, which has been shown to be involved in the development of treatment resistance, there are no reports of LEN resistance in HCC treatment under hypoxia. The purpose of our study was to elucidate the mechanism of treatment resistance to LEN under hypoxia using HCC cell lines. We confirmed LEN resistance under hypoxic conditions in HCC cell lines. There was a significant increase in the IC₅₀ value of PLC/PRF/5 cells from 13.0±0.8 μM in normoxia to 21.3±1.1 μM in hypoxia, but in HepG2 cells, the increase was not significant. To elucidate the LEN resistance mechanism of PLC/PRF/5 cells under hypoxia, we performed microarray analysis and extracted genes that are thought to be related to this mechanism. Furthermore, in-silico analysis confirmed significant changes in the extracellular matrix, and among them, FN1 encoding fibronectin was determined as the hub of the gene cluster. The expression of fibronectin in PLC/PRF/5 cells examined with immunofluorescence staining was significantly elevated in and outside of cells under hypoxia, and tended to decrease when cells were exposed to LEN under normoxia. Furthermore, the fibronectin concentration in the culture solution of PLC/PRF/5 cells examined by ELISA was 2.3 times higher under hypoxia than under normoxia under LEN(-) conditions, and 1.6 times higher under hypoxia than under normoxia under LEN(+) conditions. It is assumed that in PLC/PRF/5 cells, fibronectin is probably suppressed as an indirect effect of LEN under normoxia, but transcription factors such as HIF-1α are induced under hypoxia, thus enhancing the production of fibronectin and attenuating the effect of LEN, resulting in drug resistance. This behavior of fibronectin with LEN exposure under hypoxia is probably specific to PLC/PRF/5 cells. Further studies should verify the combined effective inhibition of fibronectin and the MAPK pathway as a promising therapeutic strategy to enhance the value of LEN in HCC treatment.

Identifying patients with atrial fibrillation during sinus rhythm on ECG: confirming the utility of artificial intelligence algorithm in a small-scale cohort without structural heart diseases

Background

Detection of atrial fibrillation (AF) out of electrocardiograph (ECG) on sinus rhythm (SR) using artificial intelligence (AI) algorithm has been widely studied within recent couple of years. Generally, it is believed that a huge number of ECGs are necessary for developing an AI-enabled ECG to be adequate to correspond to a lot of minor variations of ECGs. For example, structural heart diseases have typical ECG characteristics, but they could be a noise for the purpose of detecting the small signs of electrocardiographic signature of AF. We hypothesized that when patients with structural heart diseases are excluded, AI-enabled ECG for identifying patients with AF can be developed with a small number of ECGs.

Methods

We developed an AI-enabled ECG using a convolutional neural network to detect the electrocardiographic signature of AF present during normal sinus rhythm (NSR) using a digital, standard 10-second, 12-lead ECGs. We included all patients who newly visited the Cardiovascular Institute with at least one NSR ECG between Feb 1, 2010, and March 31, 2018. We classified patients with at least one ECG with a rhythm of AF as positive for AF (AF label) and others as negative for AF (SR label). We allocated ECGs to the training, internal validation, and testing datasets in a 7:1:2 ratio. We calculated the area under the curve (AUC) of the receiver operating characteristic curve for the internal validation dataset to select a probability threshold, which we applied to the testing dataset. We evaluated model performance on the testing dataset by calculating the AUC and the sensitivity, specificity, F1 score, and accuracy with two-sided 95% confidence intervals (CIs).

Results

We totally included 19170 patients with 12-lead ECG. After excluding patients with structural heart diseases, 12825 patients with NSR ECGs at the initial visit were identified (1262 were clinically diagnosed as AF anytime during the time course and 11563 were never diagnosed as AF). Of 11563 non-AF patients, 1818 patients who were followed over 1095 days were selected for the analysis with the SR label, to secure the robustness for maintaining SR. Of 1262 AF patients, 251 patients were selected for the analysis with the AF label, of whom a NSR ECG within 31 days before or after the index AF ECG (the first AF ECG during the time course) could be obtained. In the patients with AF label, the NSR ECG of which the date was the nearest to the index AF ECG was selected for the analysis. The AI-enabled ECG showed an AUC of 0.88 (0.84–0.92) with sensitivity 81% (72–88), specificity 80% (77–83), F1 score 50% (43–57), and overall accuracy 80% (78–83).

Conclusion

An AI-enabled ECG acquired during NSR allowed identification of patients with AF in a small population without structural heart diseases.

Funding Acknowledgement

Type of funding sources: None.

Loss of FYCO1 leads to cataract formation

Autophagy is a degradation process of cytoplasmic proteins and organelles trafficked to degradation vesicles known as autophagosomes. The conversion of LC3-I to LC3-II is an essential step of autophagosome formation, and FYCO1 is a LC3-binding protein that mediates autophagosome transport. The p62 protein also directly binds to LC3 and is degraded by autophagy. In the present study, we demonstrated that disrupting the FYCO1 gene in mice resulted in cataract formation. LC3 conversion decreased in eyes from FYCO1 knockout mice. Further, FYCO1 interacted with αA- and αB-crystallin, as demonstrated by yeast two-hybrid screening and immunoprecipitation analyses. In eyes from knockout mice, the soluble forms of αA- and αB-crystallin, the lens’s major protein components, decreased. In addition, p62 accumulated in eyes from FYCO1 knockout mice. Collectively, these findings suggested that FYCO1 recruited damaged α-crystallin into autophagosomes to protect lens cells from cataract formation.

Reprogramming of glutamine metabolism via glutamine synthetase silencing induces cisplatin resistance in A2780 ovarian cancer cells

BACKGROUND

Cisplatin (CDDP) significantly prolongs survival in various cancers, but many patients also develop resistance that results in treatment failure. Thus, this study aimed to elucidate the underlying mechanisms by which ovarian cancer cells acquire CDDP resistance.

METHODS

We evaluated the metabolic profiles in CDDP-sensitive ovarian cancer A2780 cells and CDDP-resistant A2780cis cells using capillary electrophoresis-time-of-flight mass spectrometry (CE-TOFMS). We further examined the expression of glutamine metabolism enzymes using real-time PCR and Western blot analyses. Cell viability was accessed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay.

RESULTS

The results showed that levels of glutamine, glutamate, and glutathione (GSH), a key drug resistance mediator synthesized from glutamate, were significantly elevated in A2780cis cells than those in A2780 cells. Furthermore, glutamine starvation decreased the GSH levels and CDDP resistance in A2780cis cells. Interestingly, the expression of glutamine synthetase (GS/GLUL), which synthesizes glutamine from glutamate and thereby negatively regulates GSH production, was almost completely suppressed in resistant A2780cis cells. In addition, treatment of A2780cis cells with 5-aza-2'-deoxycytidine, a DNA-demethylating agent, restored GS expression and reduced CDDP resistance. In contrast, GS knockdown in CDDP-sensitive A2780 cells induced CDDP resistance.

CONCLUSIONS

The results indicate that upregulation of GSH synthesis from glutamine via DNA methylation-mediated silencing of GS causes CDDP resistance in A2780cis cells. Therefore, glutamine metabolism could be a novel therapeutic target against CDDP resistance.

Clinical implications of coronary artery morphology of patients with ischemia and non-obstructive coronary artery disease (INOCA) -An intracoronary OCT study-

Introduction

Ischemia and non-obstructive coronary artery disease (INOCA), including microvascular spasm (MVS) and epicardial spasm, has recently attracted much attention, for which in vivo imaging evaluation for coronary artery morphology is warranted for better understanding of this disorder. Besides the improved diagnostic accuracy of optical coherence tomography (OCT) for coronary plaques, we have recently demonstrated its capability for in vivo visualization of coronary adventitial vasa vasorum (VV) and the enhanced VV formation in patients with epicardial spasm.

Purpose

We aimed to examine OCT-delineated morphological characteristics in patients with INOCA in vivo.

Methods

A total of 335 consecutive INOCA patients, who underwent pharmacological spasm provocation tests, lactate sampling, and OCT imaging over the entire length of the left anterior descending (LAD) coronary arteries, were enrolled at our institute over 68 months from April 2013. They were classified into 4 groups; control with non-cardiac chest pain, MVS, diffuse spasm (DS), or focal spasm (FS) (Fig. 1A). MVS was diagnosed when negative lactate extraction ratio (coronary orifice &lt; coronary sinus) was detected despite the absence of epicardial spasm during the spasm provocation test. DS was defined as epicardial spasm induced in more than 2 coronary segments in LAD, and FS as epicardial spasm in one segment. Quantitative analyses for adventitial inflammation and atherosclerotic changes were performed by calculating VV density and %area stenosis (AS) on OCT (Fig. 1B, E). Furthermore, index of microcirculatory resistance (IMR), a marker of microvascular disorder with a cut-off value of ≥25, was measured during intravenous infusion of adenosine, which was then correlated with VV densities in the MVS and DS groups. Coronary plaque with a necrotic core was classified as fibroatheroma (FA), and the number of OCT frames with internal VV (IVV) in the atheroma was counted.

Results

VV density was significantly higher in MVS as compared with the controls (Fig. 1B). DS was most prevalent in INOCA (Fig. 1A) with highest VV density (Fig. 1B). Patients with IMR≥25 were predominantly distributed with a gradual increase in the MVS, DS, and FS groups, but none in the controls (Fig. 1C). Importantly, there was a significant positive correlation between VV densities and IMR in the MVS and DS groups (Fig. 1D). In addition, FS had the largest plaque size and showed the highest prevalence of FA and IVV (Fig. 1E–G).

Conclusions

These results indicate that MVS and DS are characterized by vasomotion abnormalities associated with adventitial inflammation and microvascular disorder, while FS by vulnerable atherosclerotic phenotype, suggesting that OCT may be useful for screening high-risk populations in INOCA.

Figure 1

Funding Acknowledgement

Type of funding source: None

55Identification of celastramycin as a novel therapeutic agent for pulmonary arterial hypertension - high-throughput screening of 5,562 compounds

Background

Pulmonary arterial hypertension (PAH) is characterized by enhanced proliferation of pulmonary artery smooth muscle cells (PASMCs) accompanying increased production of inflammatory factors and adaptation of mitochondrial metabolism to a hyperproliferative state. However, at present, since all the drugs in clinical use target pulmonary vascular dilatation, they may not be so effective for patients with advanced PAH.

Purposes

We aimed to discover a novel drug for PAH that inhibits PASMC proliferation.

Methods

In the first screening, we examined 5,562 compounds from our original library using high-throughput screening system to discover a compound that inhibits proliferation of PASMCs from PAH patients (PAH-PASMCs). In the second screening, we performed concentration-dependent assays and counter assays with PAH-PASMCs and PASMCs from healthy donors. We also performed apoptosis assays and mechanistic analysis for inflammation, reactive oxygen species (ROS), and mitochondrial function.

Results

We found that celastramycin, a benzoyl pyrrole-type compound originally found in a bacteria extract, inhibited the proliferation of PAH-PASMCs in a dose-dependent manner with minimal effects on PASMCs from healthy donors. Moreover, celastramycin inhibited proliferation with minimal increase in apoptosis and low rate of cell death. Then, we synthesized 25 analogues of celastramycin, and finally selected the lead compound that significantly inhibited proliferation of PAH-PASMCs and reduced cytosolic ROS levels. Mechanistic analysis demonstrated that celastramycin reduced the protein levels of hypoxia-inducible factor-1α, which was abnormally activated in PAH-PASMCs and impaired aerobic metabolism, and nuclear factor-κB, which induces pro-inflammatory signals, in PAH-PASMCs compared with vehicle controls, leading to reduced secretion of inflammatory cytokines. Importantly, celastramycin treatment reduced the ROS levels in PAH-PASMCs with increased protein levels of NF-E2-related factor 2 (Nrf2), a master regulator of cellular response against oxidative stress. Furthermore, celastramycin treatment improved mitochondrial energy metabolism with recovered mitochondrial network formation in PAH-PASMCs. We also discovered that celastramycin-mediated effects on these transcriptional modulators could be regulated by zinc finger C3H1 domain-containing protein, which is a binding partner of celastramycin. Finally, celastramycin treatment ameliorated pulmonary hypertension in three experimental animal models of PH in mice and rats, accompanied by reduced inflammatory changes in the lungs.

Conclusions

These results indicate that celastramycin ameliorates pulmonary hypertension through inhibition of excessive proliferation of PAH-PASMCs, for which its anti-inflammatory and beneficial effects on mitochondrial energy metabolism may be involved. Thus, celastramycin could be a novel drug for PAH as it exerts anti-proliferative effects on PAH-PASMCs.

P6479Diagnostic and prognostic significance of serum levels of selenoprotein P in patients with pulmonary arterial hypertension

Background

Despite the recent progress in upfront combination therapy for pulmonary arterial hypertension (PAH), a useful biomarker for the disorder still remains to be developed. Selenoprotein P (SeP) is a glycoprotein secreted mainly from hepatocytes but also from other various kinds of cells, including pulmonary artery smooth muscle cells (PASMCs), to maintain selenium homeostasis and cellular energy metabolism. We have recently demonstrated that SeP expression in PASMCs is markedly up-regulated in PAH patients and plays crucial roles in the pathogenesis of the disorder. In this study, we thus examined whether serum levels of SeP could be a useful biomarker for the disorder.

Methods

In the experimental study, we performed gene expression microarray and in silico analyses to identify a novel therapeutic target for PAH. We also used the lung, serum, and cultured PAMSCs derived from patients with PAH for mechanistic experiments. In the clinical study, we enrolled a total of 65 consecutive patients with PAH who underwent right heart catheterization for hemodynamic assessment. We measured serum SeP levels and evaluated their prognostic impacts during follow-up (mean 1,520 days, IQR: 1,393–1,804 days). Serum SeP level was measured using a newly developed sol particle homogeneous immunoassay. As controls, we collected serum samples from 20 controls without any known cardiac disorders evaluated by hematological examination, echocardiography, and coronary angiography. In PAH patients, we examined the relationship between baseline SeP levels and composite endpoint of all-cause death and lung transplantation. The correlation between the absolute changes in SeP and those in hemodynamic parameters during follow-up were also examined.

Results

In the experimental study, SeP promoted PASMC proliferation through increased oxidative stress and mitochondrial metabolic dysfunction, which were associated with activated HIF-1α and dysregulated glutathione metabolism. In the clinical study, PAH patients showed significantly higher levels of serum SeP compared with controls (3.07±0.57 vs. 2.43±0.25 mg/L, P<0.0001). Higher SeP levels (cut-off point, 3.47 mg/L) were significantly associated with the composite endpoint of all-cause death and lung transplantation in PAH patients [HR: 4.85 (1.42 to 16.6), P<0.01]. Importantly, we found that absolute changes in SeP levels in PAH patients significantly correlated with those in mean pulmonary artery pressure, pulmonary vascular resistance, and cardiac index in response to PAH-specific therapy (R=0.78, 0.76, and −0.71, respectively, all P<0.0001). Furthermore, the increases in SeP levels during follow-up predicted the poor outcome in PAH patients [Figure, HR: 4.29 (1.27 to 14.4), P<0.05].

Figure 1

Conclusions

These results indicate that SeP is a novel therapeutic target of PAH and that serum SeP levels are a novel biomarker for diagnosis and assessment of treatment efficacy and long-term prognosis in PAH patients.

Acknowledgement/Funding

Grants-in-aid for Scientific Research from the Japan Agency for Medical Research and Development, Tokyo, Japan (16ek0109176h0001, 17ek0109227h0001).

P3735Incidence of bicuspid aortic valve in 16,185 neonates by echocardiographic screening in a single institution: is it really congenial?

Background

Bicuspid aortic valve (BAV) has been reported to be the most common congenital heart disease with an incidence of 1 to 2% in the general population; however, its incidence in neonates is still unclear because most of the reported incidence data are based on surgical or autopsy cases in adults.

Purpose

To elucidate the true incidence of congenital isolated BAV in neonates by echocardiographic screening in a population-based study.

Methods

We examined a total of 16,185 full-term neonates (male, 48.9%) born in our institution during either of the following two periods: September 1986 to February 2008 and October 2014 to September 2017. Mean gestational age (range) was 39.4 (36 to 42) weeks, and mean birth weight (range) was 3075 (2268 to 4622) g. On the second day after birth, we performed echocardiography and colour-Doppler flow mapping in all subjects. BAV was classified into two types on the basis of morphologicfindings in the parasternal short axis view of the aortic valve: BAV with raphe harbouring two cusps and commissures, showing a congenital fusion of two underdeveloped cusps, and BAV without raphe, showing a fish mouth appearance in systolic images. BAV associated with other congenital heart diseases such as coarctation of the aorta was excluded from this study.

Results

BAV was identified in 14 neonates (0.09%), an incidence of 0.9 in 1,000 live births. Of the 14 BAV neonates, five had BAV with raphe, whereas nine had BAV without raphe. Of the five BAV neonates with raphe, four had fusion of the right and noncoronary cusps, whereas one had that of the right and left coronary cusps. No aortic regurgitation was detected except trivial one in only one neonate, and no significant valvar stenosis was detected.

Conclusion

The incidence of BAV in neonates was much lower than previously reported incidence data. An acquired fusion of the cusps may develop in later life, and eventually may result in increased incidence of functional BAV.

Type I Congenital Plasminogen Deficiency Is not a Risk Factor for Thrombosis

The risk of thrombosis in type I congenital plasminogen (PLG) deficiency has been suggested, but is still not confirmed. We studied 40 members of two unrelated families with this disease, and found that 21 were heterozygotes of type I congenital PLG deficiency. Three of them had thrombosis, but the other 18 had no thrombosis. The percentages of family members with no history of thrombosis up to a given age among subjects with type I congenital PLG deficiency and healthy controls were analyzed by the Kaplan-Meier method. No significant difference between the two groups was observed by the generalized Wilcoxon test (p = 0.23). These results suggest that there is no significant correlation between type I congenital PLG deficiency and thrombosis.

Functional characterization of recombinant snake venom rhodocytin: rhodocytin mutant blocks CLEC-2/podoplanin-dependent platelet aggregation and lung metastasis

Essentials We generated recombinant rhodocytin that could aggregate platelets via CLEC-2. Recombinant wild-type rhodocytin formed heterooctamer with four α- and β-subunits. Asp 4 in α-subunit of rhodocytin was required for binding to CLEC-2. Inhibitory mutant of rhodocytin blocked podoplanin-dependent hematogenous metastasis.

SUMMARY

Background Rhodocytin, a disulfide-linked heterodimeric C-type lectin from Calloselasma rhodostoma consisting of α-subunits and β-subunits, induces platelet aggregation through C-type lectin-like receptor 2 (CLEC-2). CLEC-2 is a physiological binding partner of podoplanin (PDPN), which is expressed on some tumor cell types, and is involved in tumor cell-induced platelet aggregation and tumor metastasis. Thus, modified rhodocytin may be a possible source of anti-CLEC-2 drugs for both antiplatelet and antimetastasis therapy. However, its molecular function has not been well characterized, because of the lack of recombinant rhodocytin that induces platelet aggregation. Objective To produce recombinant rhodocytin, in order to verify its function with mutagenesis, and to develop an anti-CLEC-2 drug based on the findings. Methods We used Chinese hamster ovary cells to express recombinant rhodocytin (wild-type [WT] and mutant), which was analyzed for induction/inhibition of platelet aggregation with light transmission aggregometry, the formation of multimers with blue native PAGE, and binding to CLEC-2 with flow cytometry. Finally, we investigated whether mutant rhodocytin could suppress PDPN-induced metastasis in an experimental lung metastasis mouse model. Results Functional WT] rhodocytin (αWTβWT) was obtained by coexpression of both subunits. Asp4 in α-subunits of rhodocytin was required for CLEC-2 binding. αWTβWT formed a heterooctamer similarly to native rhodocytin. Moreover, an inhibitory mutant of rhodocytin (αWTβK53A/R56A), forming a heterotetramer, bound to CLEC-2 without inducing platelet aggregation, and blocked CLEC-2-PDPN interaction-dependent platelet aggregation and experimental lung metastasis. Conclusion These findings provide molecular characterization information on rhodocytin, and suggest that mutant rhodocytin could be used as a therapeutic agent to target CLEC-2.

Abstract 2513: Multi-omics-based approach to colorectal cancer metabolism

Cancer cells exhibit many metabolic alterations to acquire energy and cellular components required for their proliferation and thus, cancer specific metabolic pathways are attractive targets for cancer therapy. However, the regulation mechanisms underlying metabolic reprogramming are poorly understood. Here, we performed multi-omics-based analyses of paired normal and tumor tissues from patients with colorectal cancer (CRC) to understand the regulation mechanisms of metabolism in colorectal cancer. First, we carried out capillary electrophoresis time-of-flight mass spectrometry (CE-TOFMS)-based metabolome profiling of tumor and normal tissue obtained from 275 patients with CRC. S-adenosylmethionine (SAM), a principal methyl group donor produced by one-carbon metabolism, was the most increased metabolite in tumor tissue. Glucose was the second most decreased metabolite in tumor tissue, whereas lactate was accumulated, indicating activation of glycolysis, commonly known as the Warburg effect. Every amino acid except glutamine, the starting metabolite in glutaminolysis, was significantly accumulated in tumor tissue. Interestingly, most of the changes in metabolite levels were occurred in the adenoma stage. In addition, next-generation and Sanger sequencing analyses of genomic DNA obtained from tumor tissue revealed that metabolic alterations occurred independently of mutations in oncogenes and tumor suppressor genes, such as KRAS, APC, and TP53. Furthermore, DNA microarray analysis of paired normal and tumor tissues from CRC patients demonstrated that expression profiles of many metabolic genes were also altered at the adenoma stage. Most of genes regulating purine/pyrimidine synthesis, one-carbon metabolism and fatty acid synthesis were highly expressed, whereas those in fatty acid oxidation were down-regulated in tumor tissue. We will discuss the raised questions, which molecules contribute to the regulation of metabolic reprogramming of colorectal cancer metabolism.

Citation Format: Kiyotoshi Satoh, Tomoyoshi Soga. Multi-omics-based approach to colorectal cancer metabolism [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2513. doi:10.1158/1538-7445.AM2017-2513

C-type lectin-like receptor 2 promotes hematogenous tumor metastasis and prothrombotic state in tumor-bearing mice

Essentials The role of C-type lectin-like receptor-2 (CLEC-2) in cancer progression is unclear. CLEC-2-depleted mouse model is generated by using a rat anti-mouse CLEC-2 monoclonal antibody. CLEC-2 depletion inhibits hematogenous tumor metastasis of podoplanin-expressing B16F10 cells. CLEC-2 depletion prolongs cancer survival by suppressing thrombosis and inflammation.

SUMMARY

Background C-type lectin-like receptor 2 (CLEC-2) is a platelet activation receptor of sialoglycoprotein podoplanin, which is expressed on the surface of certain types of tumor cells. CLEC-2-podoplanin interactions facilitate hematogenous tumor metastasis. However, direct evidence of the role of CLEC-2 in hematogenous metastasis and cancer progression is lacking. Objective and methods We generated immunological CLEC-2-depleted mice by using anti-mouse CLEC-2 monoclonal antibody 2A2B10 and investigated whether CLEC-2 promoted hematogenous tumor metastasis and tumor growth and exacerbated the prognosis of mice bearing podoplanin-expressing B16F10 melanoma cells. Results Our results showed that hematogenous metastasis was significantly inhibited in CLEC-2-depleted mice. B16F10 cells co-cultured with wild-type platelets, but not with CLEC-2-deficient platelets, showed increased proliferation. However, B16F10 cell proliferation was not inhibited in CLEC-2-depleted mice. Histological analysis showed that thrombus formation in tumor vessels was significantly inhibited and functional vessel density was significantly increased in CLEC-2-depleted mice. These data suggest that CLEC-2 deficiency may inhibit thrombus formation in tumor vessels and increase the density of functional vessels, thus improving oxygen and nutrient supply to tumors, indirectly promoting tumor proliferation. Furthermore, the overall survival of CLEC-2-depleted mice was significantly prolonged, which may be due to the suppression of thrombus formation in the lungs and subsequent inhibition of systemic inflammation and cachexia. Conclusions These data provide a rationale for the targeted inhibition of CLEC-2 as a new strategy for preventing hematogenous tumor metastasis and for inhibiting cancer-related thromboembolism.

Lymphatic Architecture of Suncus Murinus (House Musk Shrew) Palatum

The architecture of craniocervical lymphatic vessels in rodents has been examined previously. In the present study, we evaluated the distribution of collecting lymphatic vessels in the palate of Suncus, which is known to retain the prototype of placental mammals and is more similar to humans in terms of jaw bone morphology when compared with rodents. Three-dimensional reconstructed images of the Suncus palatum revealed that the collecting lymphatic vessels were connected to each other via smaller branches, and ran in an antero-posterior direction in the periosteum. The vessels entered the pair of posterior palatine foramina located near the fourth premolar or the first molar bilaterally, coursed through the posterior palatine canals, and reached the pterygopalatine fossa positioned posteriorly in the palate. The collecting lymphatic vessels changed directions from medial to superior to lateral while wrapping around arteries during their course, perhaps to enable the smooth transition from the palate to the deep cervical node. Inefficient lymphatic flow in humans is attributed to the superior location of the pterygopalatine fossa in the palate when compared with its location in the Suncus.

Intracranial Aneurysm Embolization Using Interlocking Detachable Coils

The relationship between volume embolization ratio and coil compaction on the intracranial aneurysm occluded using interlocking detachable coils (IDCs) was determined.

From February 1994 to October 1996, 7 intracranial aneurysms were embolized using IDCs. Aneurysm capacity (volume) was calculated assuming that aneurysms are ellipsoid of the diameter in 3 planes. Coil volume was calculated assuming that IDCs are cylinders of primary coil.

Coil compaction was observed in aneurysms embolized at a volume embolization ratio under 25%. There was no coil compaction in aneurysms embolized at a volume embolization ratio of over 25%.

Measurement of the volume embolization ratio is useful to predict coil compaction. Intracranial aneurysms should be embolized at a volume embolization ratio of 25–33%.

Measurement of Volume Ratio to Predict Coil Compaction, on Aneurysmal Embolization

The relationship between volume embolization ratio and coil compaction on the intracranial aneurysms occluded using Guglielmi detachable coils (GDCs) was determined. From March 1997 to February 1998, 38 intracranial aneurysms were embolized using GDCs. Aneurysm volume was calculated assuming that aneurysms are ellipsoids of the diameter in three planes. Coil volume was calculated assuming that detachable coils are cylinder of primary coil. Coil compaction was observed in aneurysms embolized at a volume embolization ratio under 21%. There was no coil compaction in aneurysms embolized at a volume embolization ratio of over 21%. Measurement of the volume embolization ratio is useful to predict the coil compaction. Intracranial aneurysms should be embolized at a volume embolization ratio of 25–33%.

Endovascular Treatment Using Detachable Coils for Non-Ruptured Intracranial Aneurysm

Detachable coil embolization was performed on 34 non-ruptured cerebral aneurysms in 33 patients. Patients consisted of 28 females and five males, with an age range of 26 to 77 years.

Angiographic examination after coil embolization revealed complete or near-complete occlusion in 24 aneurysms (70.5%) and partial occlusion in three (8.8%). Detachable coil embolization was attempted unsuccessfully in seven aneurysms (20.5%).

Transient ischemic attack occurred in one case with coil migration. The combined mortality/morbidity rate was 0%.

The first case of onychomycosis in a koala (Phascolarctos cinereus) due to atypical isolates of Microsporum gypseum, a diagnostic challenge

Background and Purpose:

Superficial mycotic infections have been only poorly described in koalas and there are no reliable mycologically confirmed data regarding clinical isolation of dermatophytes in this animal. We report an 11-year-old female koala, kept in a zoo in Tokyo, Japan, and presenting with hyperkeratotic lesions and scaly plaques on forepaw claws and pads reminiscent of fungal infection.

Case Report:

Direct microscopy of the scrapings was indicative of a dermatophyte infection. By culture and subsequent repeated subculturing of clinical specimens on Sabouraud dextrose agar, Mycobiotic agar, and potato dextrose agar, two distinct strains with different colony morphotypes (designed as types I and II) were identified. Macroscopic and microscopic characteristics of the strains were suggestive of three different species, i.e. Microsporum canis, M. gypseum, and M. fulvum. However, partial sequencing of internal transcribed spacer (ITS) region of rDNA, translation elongation factor-1α (Tef-1α), and beta-tubulin (BT2) genes confirmed the identity of both isolates as M. gypseum. The animal was treated with a continuous terbinafine regimen (250 mg/kg) once daily for 12 weeks.

Conclusion:

To the best of our knowledge, the present report is the first confirmed case of dermatophytosis in a koala. The genetics underlying a variety of phenotypic traits in most classical dermatophyte species are unknown, and further studies are needed to understand this phenomenon.

Dose and dose-rate response of lymphocyte chromosome aberrations in mice chronically irradiated within a low-dose-rate range after age adjustment

The incidences of chromosome aberrations were analysed in splenic lymphocytes from mice that were continuously exposed to (137)Cs gamma rays within the low-dose-rate (LDR) range to evaluate the dose-response and dose-rate effects. Chromosome aberrations were detected by fluorescence in situ hybridisation method, and these were found to increase in frequency up to 8000 mGy at 20 mGy for 22 h d(-1) and to 700 mGy at 1 mGy for 22 h d(-1). Translocations increased in a linear quadratic manner with age in non-exposed mice. The dose-response relationship for the frequency of translocations at each dose rate (20 and 1 mGy for 22 h d(-1)) was obtained using age-adjusted multiple linear regression analysis. Values of the linear term, shown as the slope, decreased as the dose rate was reduced from 20 to 1 mGy for 22 h d(-1), indicating a positive dose-rate effect in the LDR range. These results will be useful for estimating the risk of LDR radiation exposure and radiation protection.

Imaging findings of necrotizing sialometaplasia of the parotid gland: case report and literature review

Although necrotizing sialometaplasia (NS) of the parotid gland is rare and occasionally presents as a lesion that mimics a malignant tumour, imaging findings in cases of NS have been rarely reported. We describe here a case of NS in which there was an increasing lesion manifesting overnight on the parotid gland in an 83-year-old male. We also investigated the use of pre-operative imaging based on previous reports and discuss the importance of these images in helping to guard against overzealous treatment. It is critically important to closely examine whether there are aspects of NS, such as the present case, in pre-operative MRI findings that can be useful in proper diagnosis and treatment.

Fabrication of Y2O3-Doped Zirconia/Gadolinia-Doped Ceria Bilayer Electrolyte Thin Film SOFC Cells of SOFCs by Single-Pulsed Laser Deposition Processing

An 8 -mol. % Y₂O₃-doped zirconia/10-mol. % GdO₂-doped ceria (YSZ/GDC) bilayer electrolyte and a Gd_0.5Sr_0.5CoO₃ (GSCO) cathode were deposited by a single-processing, pulsed laser deposition (PLD) method to fabricate anode support cells. No additional heat treatment was needed. Laser frequencies of 10, 20, and 100 Hz were used to deposit bilayer electrolytes between the NiO–YSZ (NiO:YSZ = 60:40 wt. %) anode substrate and the GSCO cathode thin film. The GDC thin film produced at 10 Hz was smooth, well-crystallized, and highly dense. The crystallinity of the GSCO cathode on the GDC was also improved. We concluded the GDC crystallinity affected the crystallinity of the cathode thin film. The resistivity of the YSZ single layer (5.7 μm thickness) was 1.4 times higher than that of the YSZ/GDC bilayer (YSZ 3.0 μm thickness, GDC 2.7 μm thickness) at 600 °C and that of the YSZ-GDC interface became low. The optimum YSZ thickness was found to be approximately 3.0 μm, at which thickness there was effective blocking of the passage of hydrogen molecules and electrons. A cell with a YSZ (3.0 μm thickness, fabricated at 20 Hz)/GDC (5.0 μm thickness, fabricated at 10 Hz) bilayer and GSCO cathode thin film exhibited a maximum power density of 400 mW·cm^–2 at a comparatively low temperature of 600 °C.