Frequency of HLA-DR+CD38hi T cells identifies and quantifies T-cell activation in hemophagocytic lymphohistiocytosis, hyperinflammation, and immune regulatory disorders

BACKGROUND

Quantifying T-cell activation is essential for the diagnosis and evaluation of treatment response in various hyperinflammatory and immune regulatory disorders, including hemophagocytic lymphohistiocytosis. Plasma soluble IL-2 receptor (sIL-2R) is a well-established biomarker for evaluating systemic T-cell activation. However, the limited availability of sIL-2R testing could result in delayed diagnosis. Furthermore, high sIL-2R levels may not always reflect T-cell activation.

OBJECTIVES

To address these limitations, this study investigated whether cell surface markers of T-cell activation, HLA-DR, and CD38, as assessed by flow cytometry, could be used to quantify systemic T-cell activation in a variety of inflammatory disease states and examine its correlation with sIL-2R levels.

METHODS

Results for sIL-2R, CXCL9, and ferritin assays were obtained from patient's medical records. Frequency of HLA-DR+CD38high(hi) T-cells was assessed in different T-cell subsets using flow cytometry.

RESULTS

In this study's cohort, activation in total CD8+ T (r = 0.65; P < .0001) and CD4+ (r = 0.42; P < .0001) T-cell subsets significantly correlated with plasma sIL-2R levels. At the disease onset, the frequency of HLA-DR+CD38hi T cells in CD8+ T (r = 0.65, P < .0001) and CD4+ T (r = 0.77; P < .0001) effector memory (TEM) compartments correlated strongly with sIL-2R levels. Evaluation of T-cell activation markers in follow-up samples also revealed a positive correlation for both CD4+ TEM and CD8+ TEM activation with sIL-2R levels; thus, attesting its utility in initial diagnosis and in evaluating treatment response. The frequency of HLA-DR+CD38hi T-cells in the CD8+ TEM compartment also correlated with plasma CXCL9 (r = 0.42; P = .0120) and ferritin levels (r = 0.32; P = .0037).

CONCLUSIONS

This study demonstrates that flow cytometry-based direct T-cell activation assessed by HLA-DR+CD38hi T cells accurately quantifies T-cell activation and strongly correlates with sIL-2R levels across a spectrum of hyperinflammatory and immune dysregulation disorders.

Ocular motor nerve palsy in patients with diabetes: High-resolution MR imaging of nerve enhancement

OBJECTIVE

To evaluate the extent of signal abnormality in impaired ocular motor nerves using high signal and spatial resolution MRI sequences and to discuss the involvement of inflammatory or microvascular impairment in patients with diabetic ophthalmoplegia.

METHODS

We conducted a retrospective study of 10 patients referred for acute ocular motor nerve palsy in the context of diabetes mellitus from September 15th, 2021 to April 24th, 2022. 3T MRI evaluation included diffusion, 3D TOF, FLAIR, coronal STIR and post-injection 3D T1 SPACE DANTE sequences.

RESULTS

Ten patients were included: 9 males and 1 female aged from 46 to 79 years. Five patients presented with cranial nerve (CN) III palsy, and 5 presented with CN VI palsy. Third nerve palsy was pupil-sparing in 4 patients and pupil-involved in 1 patient. Pain was associated in all patients with CN III deficiencies and in 2 patients CN VI deficiencies. In all patients, MRI sequences ruled out mass effect and vascular pathology, such as acute stroke or aneurysm. Eight patients presented with STIR hypersignals, some with enlargement of the involved nerve. The diagnosis was confirmed through a post-injection 3D T1 SPACE DANTE sequence, which showed extended enhancement along the abnormal portion of the nerve.

CONCLUSION

High-resolution MRI evaluation of diplopia in diabetic patients is used to rule out a diagnosis of acute stroke and contributes to the positive diagnosis of ocular motor nerve impairment, possibly combining the influences of inflammatory and microvascular phenomena. Dedicated MR imaging should be included in the initial diagnosis and longitudinal follow-up of patients with diabetic ophthalmoplegia.

DNA-PKcs as an upstream mediator of OCT4-induced MYC activation in small cell lung cancer

Small cell lung cancer (SCLC) is a neuroendocrine tumor noted for the rapid development of both metastases and resistance to chemotherapy. High mutation burden, ubiquitous loss of TP53 and RB1, and a mutually exclusive amplification of MYC gene family members contribute to genomic instability and make the development of new targeted agents a challenge. Previously, we reported a novel OCT4-induced MYC transcriptional activation pathway involving c-MYC, pOCT4^S111, and MAPKAPK2 in progressive neuroblastoma, also a neuroendocrine tumor. Using tumor microarray analysis of clinical samples and preclinical models, we now report a correlation in expression between these proteins in SCLC. In correlating c-MYC protein expression with genomic amplification, we determined that some SCLC cell lines exhibited high c-MYC without genomic amplification, implying amplification-independent MYC activation. We then confirmed direct interaction between OCT4 and DNA-PKcs and identified specific OCT4 and DNA-PKcs binding sites. Knock-down of both POU5F1 (encoding OCT4) and PRKDC (encoding DNA-PKcs) resulted in decreased c-MYC expression. Further, we confirmed binding of OCT4 to the promoter/enhancer region of MYC. Together, these data establish the presence of a DNA-PKcs/OCT4/c-MYC pathway in SCLCs. We then disruptively targeted this pathway and demonstrated anticancer activity in SCLC cell lines and xenografts using both DNA-PKcs inhibitors and a protein-protein interaction inhibitor of DNA-PKcs and OCT4. In conclusion, we demonstrate here that DNA-PKcs can mediate high c-MYC expression in SCLCs, and that this pathway may represent a new therapeutic target for SCLCs with high c-MYC expression.

mTOR inhibition attenuates cTfh cell dysregulation and chronic T-cell activation in multilineage immune cytopenias

mTOR inhibitors such as sirolimus are increasingly used in the management of multilineage immune cytopenia (m-IC) in children. Although sirolimus is effective in improving IC, it is unclear how sirolimus affects the broader immune dysregulation associated with m-IC. We profiled T- and B-cell subsets longitudinally and measured cytokines and chemokines before and after sirolimus treatment. Eleven of the 12 patients with m-IC who tolerated sirolimus were followed for a median duration of 17 months. All patients had an improvement in IC, and sirolimus therapy did not result in significant decreases in T-, B- and NK-cell numbers. However, the expansion and activation of circulating T follicular helper and the Th1 bias noted before the initiation of sirolimus were significantly decreased. Features of chronic T-cell activation and exhaustion within effector memory compartments of CD4+ and CD8+ T cells decreased with sirolimus therapy. Corresponding to these changes, plasma levels of CXCL9 and CXCL10 also decreased. Interestingly, no significant improvement in the proportion of class-switched memory B cells or frequencies of CD4+ naive T cells were noted. Longer follow-up and additional studies are needed to validate these findings and evaluate the effect of sirolimus on B-cell maturation.

Distinguishing immune activation and inflammatory signatures of multisystem inflammatory syndrome in children (MIS-C) versus hemophagocytic lymphohistiocytosis (HLH)

BACKGROUND

Multisystem inflammatory syndrome in children (MIS-C) is a potentially life-threatening sequela of severe acute respiratory syndrome coronavirus 2 infection characterized by hyperinflammation and multiorgan dysfunction. Although hyperinflammation is a prominent manifestation of MIS-C, there is limited understanding of how the inflammatory state of MIS-C differs from that of well-characterized hyperinflammatory syndromes such as hemophagocytic lymphohistiocytosis (HLH).

OBJECTIVES

We sought to compare the qualitative and quantitative inflammatory profile differences between patients with MIS-C, coronavirus disease 2019, and HLH.

METHODS

Clinical data abstraction from patient charts, T-cell immunophenotyping, and multiplex cytokine and chemokine profiling were performed for patients with MIS-C, patients with coronavirus disease 2019, and patients with HLH.

RESULTS

We found that both patients with MIS-C and patients with HLH showed robust T-cell activation, markers of senescence, and exhaustion along with elevated TH1 and proinflammatory cytokines such as IFN-γ, C-X-C motif chemokine ligand 9, and C-X-C motif chemokine ligand 10. In comparison, the amplitude of T-cell activation and the levels of cytokines/chemokines were higher in patients with HLH when compared with patients with MIS-C. Distinguishing inflammatory features of MIS-C included elevation in TH2 inflammatory cytokines such as IL-4 and IL-13 and cytokine mediators of angiogenesis, vascular injury, and tissue repair such as vascular endothelial growth factor A and platelet-derived growth factor. Immune activation and hypercytokinemia in MIS-C resolved at follow-up. In addition, when these immune parameters were correlated with clinical parameters, CD8+ T-cell activation correlated with cardiac dysfunction parameters such as B-type natriuretic peptide and troponin and inversely correlated with platelet count.

CONCLUSIONS

Overall, this study characterizes unique and overlapping immunologic features that help to define the hyperinflammation associated with MIS-C versus HLH.

Increasing sample diversity in psychiatric genetics - Introducing a new cohort of patients with schizophrenia and controls from Vietnam - Results from a pilot study

OBJECTIVES

Genome-Wide Association Studies (GWAS) of Schizophrenia (SCZ) have provided new biological insights; however, most cohorts are of European ancestry. As a result, derived polygenic risk scores (PRS) show decreased predictive power when applied to populations of different ancestries. We aimed to assess the feasibility of a large-scale data collection in Hanoi, Vietnam, contribute to international efforts to diversify ancestry in SCZ genetic research and examine the transferability of SCZ-PRS to individuals of Vietnamese Kinh ancestry.

METHODS

In a pilot study, 368 individuals (including 190 SCZ cases) were recruited at the Hanoi Medical University's associated psychiatric hospitals and outpatient facilities. Data collection included sociodemographic data, baseline clinical data, clinical interviews assessing symptom severity and genome-wide SNP genotyping. SCZ-PRS were generated using different training data sets: (i) European, (ii) East-Asian and (iii) trans-ancestry GWAS summary statistics from the latest SCZ GWAS meta-analysis.

RESULTS

SCZ-PRS significantly predicted case status in Vietnamese individuals using mixed-ancestry (R² liability = 4.9%, p = 6.83 × 10^-8), East-Asian (R² liability = 4.5%, p = 2.73 × 10^-7) and European (R² liability = 3.8%, p = 1.79 × 10^-6) discovery samples.

DISCUSSION

Our results corroborate previous findings of reduced PRS predictive power across populations, highlighting the importance of ancestral diversity in GWA studies.

Continuing Medical Education in Vietnam: A Weighted Analysis from Healthcare Professionals' Perception and Evaluation

PURPOSE

Continuing medical education (CME) is a compulsory requirement for every health professional. However, to date, little is known about the effectiveness of CME in Vietnam. This study assessed CME programs based on attendees' perception and evaluation.

METHODS

A cross-sectional study was conducted during a five-month period in all 62 CME courses at a university hospital. A self-report, anonymous questionnaire was distributed to the participants during the course and was collected at the end of the course. The questionnaire included questions about demographic characteristics, experiences during the course and participants' perception and evaluation as measured by the 19-item Program Evaluation Instrument (PEI). A higher score on the PEI indicates a higher level of positive reaction toward CME programs.

RESULTS

Among 1312 participants in the analysis, the majority were females (58.1%) with a mean age of 34.5 (SD = 10.6) years. Almost all participants had good, positive perceptions toward CME. However, about 5% of participants reported CME a waste of time. Participants reported a high score on the PEI (95.0±8.9) and all four dimensions including program objectives (20.7±2.2), learner's objectives (18.8±2.3), teacher's behavior (25.7±2.7) and program satisfaction (29.7±3.4). While there was no association between demographic characteristics and PEI score, attendance rate during the courses and perceptions toward CME were positively associated with PEI score.

CONCLUSION

CME programs receive positive reaction and evaluation from healthcare professionals and are helpful in providing and updating knowledge, attitude and practice in Vietnam. However, further studies are needed in other settings and specialties to fully understand the effectiveness of CME in Vietnam.

Fungal Planet description sheets: 1284-1382

Novel species of fungi described in this study include those from various countries as follows: Antartica, Cladosporium austrolitorale from coastal sea sand. Australia, Austroboletus yourkae on soil, Crepidotus innuopurpureus on dead wood, Curvularia stenotaphri from roots and leaves of Stenotaphrum secundatum and Thecaphora stajsicii from capsules of Oxalis radicosa. Belgium, Paraxerochrysium coryli (incl. Paraxerochrysium gen. nov.) from Corylus avellana. Brazil, Calvatia nordestina on soil, Didymella tabebuiicola from leaf spots on Tabebuia aurea, Fusarium subflagellisporum from hypertrophied floral and vegetative branches of Mangifera indica and Microdochium maculosum from living leaves of Digitaria insularis. Canada, Cuphophyllus bondii from a grassland. Croatia, Mollisia inferiseptata from a rotten Laurus nobilis trunk. Cyprus, Amanita exilis on calcareous soil. Czech Republic, Cytospora hippophaicola from wood of symptomatic Vaccinium corymbosum. Denmark, Lasiosphaeria deviata on pieces of wood and herbaceous debris. Dominican Republic, Calocybella goethei among grass on a lawn. France (Corsica), Inocybe corsica on wet ground. France (French Guiana), Trechispora patawaensis on decayed branch of unknown angiosperm tree and Trechispora subregularis on decayed log of unknown angiosperm tree. Germany, Paramicrothecium sambuci (incl. Paramicrothecium gen. nov.) on dead stems of Sambucus nigra. India, Aureobasidium microtermitis from the gut of a Microtermes sp. termite, Laccaria diospyricola on soil and Phylloporia tamilnadensis on branches of Catunaregam spinosa. Iran, Pythium serotinoosporum from soil under Prunus dulcis. Italy, Pluteus brunneovenosus on twigs of broadleaved trees on the ground. Japan, Heterophoma rehmanniae on leaves of Rehmannia glutinosa f. hueichingensis. Kazakhstan, Murispora kazachstanica from healthy roots of Triticum aestivum. Namibia, Caespitomonium euphorbiae (incl. Caespitomonium gen. nov.) from stems of an Euphorbia sp. Netherlands, Alfaria junci, Myrmecridium junci, Myrmecridium juncicola, Myrmecridium juncigenum, Ophioceras junci, Paradinemasporium junci (incl. Paradinemasporium gen. nov.), Phialoseptomonium junci, Sporidesmiella juncicola, Xenopyricularia junci and Zaanenomyces quadripartis (incl. Zaanenomyces gen. nov.), from dead culms of Juncus effusus, Cylindromonium everniae and Rhodoveronaea everniae from Evernia prunastri, Cyphellophora sambuci and Myrmecridium sambuci from Sambucus nigra, Kiflimonium junci, Sarocladium junci, Zaanenomyces moderatricis-academiae and Zaanenomyces versatilis from dead culms of Juncus inflexus, Microcera physciae from Physcia tenella, Myrmecridium dactylidis from dead culms of Dactylis glomerata, Neochalara spiraeae and Sporidesmium spiraeae from leaves of Spiraea japonica, Neofabraea salicina from Salix sp., Paradissoconium narthecii (incl. Paradissoconium gen. nov.) from dead leaves of Narthecium ossifragum, Polyscytalum vaccinii from Vaccinium myrtillus, Pseudosoloacrosporiella cryptomeriae (incl. Pseudosoloacrosporiella gen. nov.) from leaves of Cryptomeria japonica, Ramularia pararhabdospora from Plantago lanceolata, Sporidesmiella pini from needles of Pinus sylvestris and Xenoacrodontium juglandis (incl. Xenoacrodontium gen. nov. and Xenoacrodontiaceae fam. nov.) from Juglans regia. New Zealand, Cryptometrion metrosideri from twigs of Metrosideros sp., Coccomyces pycnophyllocladi from dead leaves of Phyllocladus alpinus, Hypoderma aliforme from fallen leaves Fuscopora solandri and Hypoderma subiculatum from dead leaves Phormium tenax. Norway, Neodevriesia kalakoutskii from permafrost and Variabilispora viridis from driftwood of Picea abies. Portugal, Entomortierella hereditatis from a biofilm covering a deteriorated limestone wall. Russia, Colpoma junipericola from needles of Juniperus sabina, Entoloma cinnamomeum on soil in grasslands, Entoloma verae on soil in grasslands, Hyphodermella pallidostraminea on a dry dead branch of Actinidia sp., Lepiota sayanensis on litter in a mixed forest, Papiliotrema horticola from Malus communis, Paramacroventuria ribis (incl. Paramacroventuria gen. nov.) from leaves of Ribes aureum and Paramyrothecium lathyri from leaves of Lathyrus tuberosus. South Africa, Harzia combreti from leaf litter of Combretum collinum ssp. sulvense, Penicillium xyleborini from Xyleborinus saxesenii, Phaeoisaria dalbergiae from bark of Dalbergia armata, Protocreopsis euphorbiae from leaf litter of Euphorbia ingens and Roigiella syzygii from twigs of Syzygium chordatum. Spain, Genea zamorana on sandy soil, Gymnopus nigrescens on Scleropodium touretii, Hesperomyces parexochomi on Parexochomus quadriplagiatus, Paraphoma variabilis from dung, Phaeococcomyces kinklidomatophilus from a blackened metal railing of an industrial warehouse and Tuber suaveolens in soil under Quercus faginea. Svalbard and Jan Mayen, Inocybe nivea associated with Salix polaris. Thailand, Biscogniauxia whalleyi on corticated wood. UK, Parasitella quercicola from Quercus robur. USA, Aspergillus arizonicus from indoor air in a hospital, Caeliomyces tampanus (incl. Caeliomyces gen. nov.) from office dust, Cippumomyces mortalis (incl. Cippumomyces gen. nov.) from a tombstone, Cylindrium desperesense from air in a store, Tetracoccosporium pseudoaerium from air sample in house, Toxicocladosporium glendoranum from air in a brick room, Toxicocladosporium losalamitosense from air in a classroom, Valsonectria portsmouthensis from air in men's locker room and Varicosporellopsis americana from sludge in a water reservoir. Vietnam, Entoloma kovalenkoi on rotten wood, Fusarium chuoi inside seed of Musa itinerans, Micropsalliota albofelina on soil in tropical evergreen mixed forests and Phytophthora docyniae from soil and roots of Docynia indica. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Osieck ER, Jurjević Ž, et al. 2021. Fungal Planet description sheets: 1284-1382. Persoonia 47: 178-374. https://doi.org/10.3767/persoonia.2021.47.06.

Mathematical models to describe the growth curves of Vietnamese Ri chicken

Ri chicken is the most popular backyard chicken breed in Vietnam, but little is known about the growth curve of this breed. This study compared the performances of models with three parameters (Gompertz, Brody, and Logistic) and models containing four parameters (Richards, Bridges, and Janoschek) for describing the growth of Ri chicken. The bodyweight of Ri chicken was recorded weekly from week 1 to week 19. Growth models were fitted using minpack.lm package in R software and Akaike's information criterion (AIC), Bayesian information criterion (BIC), and root mean square error (RMSE) were used for model comparison. Based on these criteria, the models having four parameters showed better performance than the ones with three parameters, and the Richards model was the best one for males and females. The lowest and highest value of asymmetric weights (α) were obtained by Bridges and Brody models for each of sexes, respectively. Age and weight estimated by the Richard model were 8.46 and 7.51 weeks and 696.88 and 487.58 g for males and for females, respectively. Differences in the growth curves were observed between males and female chicken. Overall, the results suggested using the Richards model for describing the growth curve of Ri chickens. Further studies on the genetics and genomics of the obtained growth parameters are required before using them for the genetic improvement of Ri chickens.

ALT neuroblastoma chemoresistance due to telomere dysfunction-induced ATM activation is reversible with ATM inhibitor AZD0156

Cancers overcome replicative immortality by activating either telomerase or an alternative lengthening of telomeres (ALT) mechanism. ALT occurs in ~25% of high-risk neuroblastomas, and progression in patients with ALT neuroblastoma during or after front-line therapy is frequent and often fatal. Temozolomide + irinotecan is commonly used as salvage therapy for neuroblastoma. Patient-derived cell lines and xenografts established from patients with relapsed ALT neuroblastoma demonstrated de novo resistance to temozolomide + irinotecan [SN-38 in vitro, P < 0.05; in vivo mouse event-free survival (EFS), P < 0.0001] vs. telomerase-positive neuroblastomas. We observed that ALT neuroblastoma cells manifested constitutive ataxia-telangiectasia mutated (ATM) activation due to spontaneous telomere dysfunction which was not observed in telomerase-positive neuroblastoma cells. We demonstrated that induction of telomere dysfunction resulted in ATM activation that, in turn, conferred resistance to temozolomide + SN-38 (4.2-fold change in IC₅₀, P < 0.001). ATM knockdown (shRNA) or inhibition using a clinical-stage small-molecule inhibitor (AZD0156) reversed resistance to temozolomide + irinotecan in ALT neuroblastoma cell lines in vitro (P < 0.001) and in four ALT xenografts in vivo (EFS, P < 0.0001). AZD0156 showed modest to no enhancement of temozolomide + irinotecan activity in telomerase-positive neuroblastoma cell lines and xenografts. Ataxia telangiectasia and Rad3 related (ATR) inhibition using AZD6738 did not enhance temozolomide + SN-38 activity in ALT neuroblastoma cells. Thus, ALT neuroblastoma chemotherapy resistance occurs via ATM activation and is reversible with ATM inhibitor AZD0156. Combining AZD0156 with temozolomide + irinotecan warrants clinical testing for neuroblastoma.

Fungal Planet description sheets: 1284-1382

Novel species of fungi described in this study include those from various countries as follows: Antartica, Cladosporium austrolitorale from coastal sea sand. Australia, Austroboletus yourkae on soil, Crepidotus innuopurpureus on dead wood, Curvularia stenotaphri from roots and leaves of Stenotaphrum secundatum and Thecaphora stajsicii from capsules of Oxalis radicosa. Belgium, Paraxerochrysium coryli (incl. Paraxerochrysium gen. nov.) from Corylus avellana. Brazil, Calvatia nordestina on soil, Didymella tabebuiicola from leaf spots on Tabebuia aurea, Fusarium subflagellisporum from hypertrophied floral and vegetative branches of Mangifera indica and Microdochium maculosum from living leaves of Digitaria insularis. Canada, Cuphophyllus bondii from a grassland. Croatia, Mollisia inferiseptata from a rotten Laurus nobilis trunk. Cyprus, Amanita exilis on calcareous soil. Czech Republic, Cytospora hippophaicola from wood of symptomatic Vaccinium corymbosum. Denmark, Lasiosphaeria deviata on pieces of wood and herbaceous debris. Dominican Republic, Calocybella goethei among grass on a lawn. France (Corsica), Inocybe corsica on wet ground. France (French Guiana), Trechispora patawaensis on decayed branch of unknown angiosperm tree and Trechispora subregularis on decayed log of unknown angiosperm tree. Germany, Paramicrothecium sambuci (incl. Paramicrothecium gen. nov.) on dead stems of Sambucus nigra. India, Aureobasidium microtermitis from the gut of a Microtermes sp. termite, Laccaria diospyricola on soil and Phylloporia tamilnadensis on branches of Catunaregam spinosa. Iran, Pythium serotinoosporum from soil under Prunus dulcis. Italy, Pluteus brunneovenosus on twigs of broadleaved trees on the ground. Japan, Heterophoma rehmanniae on leaves of Rehmannia glutinosa f. hueichingensis. Kazakhstan, Murispora kazachstanica from healthy roots of Triticum aestivum. Namibia, Caespitomonium euphorbiae (incl. Caespitomonium gen. nov.) from stems of an Euphorbia sp. Netherlands, Alfaria junci, Myrmecridium junci, Myrmecridium juncicola, Myrmecridium juncigenum, Ophioceras junci, Paradinemasporium junci (incl. Paradinemasporium gen. nov.), Phialoseptomonium junci, Sporidesmiella juncicola, Xenopyricularia junci and Zaanenomyces quadripartis (incl. Zaanenomyces gen. nov.), from dead culms of Juncus effusus, Cylindromonium everniae and Rhodoveronaea everniae from Evernia prunastri, Cyphellophora sambuci and Myrmecridium sambuci from Sambucus nigra, Kiflimonium junci, Sarocladium junci, Zaanenomyces moderatricis-academiae and Zaanenomyces versatilis from dead culms of Juncus inflexus, Microcera physciae from Physcia tenella, Myrmecridium dactylidis from dead culms of Dactylis glomerata, Neochalara spiraeae and Sporidesmium spiraeae from leaves of Spiraea japonica, Neofabraea salicina from Salix sp., Paradissoconium narthecii (incl. Paradissoconium gen. nov.) from dead leaves of Narthecium ossifragum, Polyscytalum vaccinii from Vaccinium myrtillus, Pseudosoloacrosporiella cryptomeriae (incl. Pseudosoloacrosporiella gen. nov.) from leaves of Cryptomeria japonica, Ramularia pararhabdospora from Plantago lanceolata, Sporidesmiella pini from needles of Pinus sylvestris and Xenoacrodontium juglandis (incl. Xenoacrodontium gen. nov. and Xenoacrodontiaceae fam. nov.) from Juglans regia. New Zealand, Cryptometrion metrosideri from twigs of Metrosideros sp., Coccomyces pycnophyllocladi from dead leaves of Phyllocladus alpinus, Hypoderma aliforme from fallen leaves Fuscopora solandri and Hypoderma subiculatum from dead leaves Phormium tenax. Norway, Neodevriesia kalakoutskii from permafrost and Variabilispora viridis from driftwood of Picea abies. Portugal, Entomortierella hereditatis from a biofilm covering a deteriorated limestone wall. Russia, Colpoma junipericola from needles of Juniperus sabina, Entoloma cinnamomeum on soil in grasslands, Entoloma verae on soil in grasslands, Hyphodermella pallidostraminea on a dry dead branch of Actinidia sp., Lepiota sayanensis on litter in a mixed forest, Papiliotrema horticola from Malus communis, Paramacroventuria ribis (incl. Paramacroventuria gen. nov.) from leaves of Ribes aureum and Paramyrothecium lathyri from leaves of Lathyrus tuberosus. South Africa, Harzia combreti from leaf litter of Combretum collinum ssp. sulvense, Penicillium xyleborini from Xyleborinus saxesenii, Phaeoisaria dalbergiae from bark of Dalbergia armata, Protocreopsis euphorbiae from leaf litter of Euphorbia ingens and Roigiella syzygii from twigs of Syzygium chordatum. Spain, Genea zamorana on sandy soil, Gymnopus nigrescens on Scleropodium touretii, Hesperomyces parexochomi on Parexochomus quadriplagiatus, Paraphoma variabilis from dung, Phaeococcomyces kinklidomatophilus from a blackened metal railing of an industrial warehouse and Tuber suaveolens in soil under Quercus faginea. Svalbard and Jan Mayen, Inocybe nivea associated with Salix polaris. Thailand, Biscogniauxia whalleyi on corticated wood. UK, Parasitella quercicola from Quercus robur. USA, Aspergillus arizonicus from indoor air in a hospital, Caeliomyces tampanus (incl. Caeliomyces gen. nov.) from office dust, Cippumomyces mortalis (incl. Cippumomyces gen. nov.) from a tombstone, Cylindrium desperesense from air in a store, Tetracoccosporium pseudoaerium from air sample in house, Toxicocladosporium glendoranum from air in a brick room, Toxicocladosporium losalamitosense from air in a classroom, Valsonectria portsmouthensis from air in men's locker room and Varicosporellopsis americana from sludge in a water reservoir. Vietnam, Entoloma kovalenkoi on rotten wood, Fusarium chuoi inside seed of Musa itinerans, Micropsalliota albofelina on soil in tropical evergreen mixed forests and Phytophthora docyniae from soil and roots of Docynia indica. Morphological and culture characteristics are supported by DNA barcodes. Citation: Crous PW, Osieck ER, Jurjević Ž, et al. 2021. Fungal Planet description sheets: 1284-1382. Persoonia 47: 178-374. https://doi.org/10.3767/persoonia.2021.47.06.

The O6-methyguanine-DNA methyltransferase inhibitor O6-benzylguanine enhanced activity of temozolomide + irinotecan against models of high-risk neuroblastoma

DNA-damaging chemotherapy is a major component of therapy for high-risk neuroblastoma, and patients often relapse with treatment-refractory disease. We hypothesized that DNA repair genes with increased expression in alkylating agent resistant models would provide therapeutic targets for enhancing chemotherapy. In-vitro cytotoxicity of alkylating agents for 12 patient-derived neuroblastoma cell lines was assayed using DIMSCAN, and mRNA expression of 57 DNA repair, three transporter, and two glutathione synthesis genes was assessed by TaqMan low-density array (TLDA) with further validation by qRT-PCR in 26 cell lines. O6-methylguanine-DNA methyltransferase (MGMT) mRNA was upregulated in cell lines with greater melphalan and temozolomide (TMZ) resistance. MGMT expression also correlated significantly with resistance to TMZ+irinotecan (IRN) (in-vitro as the SN38 active metabolite). Forced overexpression of MGMT (lentiviral transduction) in MGMT non-expressing cell lines significantly increased TMZ+SN38 resistance. The MGMT inhibitor O6-benzylguanine (O6BG) enhanced TMZ+SN38 in-vitro cytotoxicity, H2AX phosphorylation, caspase-3 cleavage, and apoptosis by terminal deoxynucleotidyl transferase dUTP nick end labeling. TMZ+IRN+O6BG delayed tumor growth and increased survival relative to TMZ+IRN in two of seven patient-derived xenografts established at time of death from progressive neuroblastoma. We demonstrated that high MGMT expression was associated with resistance to alkylating agents and TMZ+IRN in preclinical neuroblastoma models. The MGMT inhibitor O6BG enhanced the anticancer effect of TMZ+IRN in vitro and in vivo. These results support further preclinical studies exploring MGMT as a therapeutic target and biomarker of TMZ+IRN resistance in high-risk neuroblastoma.

Janus kinase inhibitors for atopic dermatitis: a promising treatment modality

Atopic dermatitis (AD) is chronic, pruritic, inflammatory skin disease that affects a significant portion of the population in industrialized nations. For nonresponders to conventional therapies, AD can significantly reduce sleep quality and quality of life. AD pathogenesis is multifactorial and involves multiple immune pathways, with recent evidence of T helper (Th)2, Th17 and Th22 axis attenuation in various AD endotypes and racial subtypes. Inhibition of the conserved Janus kinase (JAK) signalling pathway represents a promising therapeutic avenue to reduce the activation of multiple proinflammatory mediators involved in AD pathogenesis. JAK inhibitors exist in both oral and topical forms with variable specificity for the receptor tyrosine kinases JAK1, JAK2, JAK3 and tyrosine kinase 2. Oral formulations include abrocitinib, upadacitinib, baricitinib and gusacitinib, and are most appropriate for patients with moderate to severe AD. Emerging topical formulation in development include ruxolitinib and deglocitinib, which may be used in patients with localized AD and also adjunctively with systemic therapy in patients with more severe disease. With observed rapidity in itch relief and accompanying dramatic reduction in inflammatory lesion count, JAK inhibitors represent a promising new treatment to revolutionize the management of AD.

Feasibility and Safety of Laparoscopic Radical Colectomy for T4b Colon Cancer at a University Hospital in Vietnam

BACKGROUND

The choice of optimal treatment strategies for T4b colon cancers has still been discussed, particularly the initiation of neoadjuvant therapy or surgery. We conducted this study to evaluate the safety and feasibility of laparoscopic multivisceral resection for T4b colon cancers.

METHODS

We used the retrospective design to include all 43 patients with T4b colon cancer at a university hospital in Vietnam from March 2017 to March 2019. All patients were followed 30 days after the surgery, and information about the day of the first flatus, length of hospital stay, iatrogenic complications, postoperative morbidity, mortality, and adjuvant chemotherapy was collected.

RESULTS

The mean operating time was 187 minutes (ranging from 80 to 310), the mean blood loss was 64.3 ml (5-200), and the conversion rate was 2.3%. The mean number of lymph nodes harvested was 15.5 (SD = 8.06), and 33 patients (76.7%) had at least 12 lymph nodes harvested. A total of 21 patients (48.8%) had lymph node metastases with a mean number of lymph node metastases of 1.89 (SD = 3.4). The radial resection margin was R0 in all 43 patients (100%). The median time until the first flatus and hospital stay were 3 days (2-5) and 7.1 (6-11) days, respectively. There was no mortality at 30 days postoperatively, and one patient had iatrogenic complication (2.3%).

CONCLUSION

Laparoscopic radical colectomy was feasible and safe for patients with T4b colon cancer except those requiring major and complicated reconstruction.

Abstract 2299: Sarcoma as second cancer in pediatric cancer survivors: Large population analysis

Introduction: As the prognosis of a pediatric cancer continues to improve, the burden of long term therapy effects, including subsequent malignant neoplasm (SMN), in survivors is an increasing epidemiologic concern. The mortality rate from cancer in the pediatric population decreased from 6.5 per 100,000 in 1970 to 2.3 in 2015, indicating more chance of SMNs. Sarcoma as a SMN in pediatrics has important clinical significance and has been extensively reported globally. We quantified the percentage of sarcoma as second cancer and determined the primary cancer distribution for patients with sarcoma as second cancer.

Methods: The Surveillance, Epidemiology, and End Results (SEER) database, which includes 28% of the U.S population and data from 18 state cancer registries (SEER-18), was probed for the overall incidence of SMN in pediatric cancer survivors and the incidence of sarcoma as the SMN specifically.

Results: Our SEER database analysis found that out of 75,665 cases of primary pediatric malignancies, 1218 (1.61%) developed SMN. The second most common SMN was sarcoma, accounting for 14.37% of them in pediatric population. The breakdown of sarcoma into sub groups showed that osteosarcoma, fibrosarcoma, and rhabdomyosarcoma are the most common second sarcomas seen in pediatric cancer survivors. Finally, we looked at the distribution of primary cancer in pediatric cancer survivors who developed sarcoma as a SMN. We found that retinoblastoma, lymphoid leukemia, and Hodgkin lymphomas were the most common types of primary cancer. Similar results were reported among different racial groups around the world, which show a universal trend of sarcomas as second cancers in pediatric cancer survivors.

Conclusion: By analyzing the SEER database, we corroborated previous findings, suggesting that about 14% of SMN after a childhood cancer is encompassed by sarcoma. The exact etiology of cancer, be it primary predisposition or secondary to exposures, is uncertain. Radiation and chemotherapies used in patients with pediatric cancers can be carcinogenic. Our study highlights the need for development of novel non-DNA damaging or alternate antineoplastic therapies to avoid the long-term potential of development of SMN.

Citation Format: Monish Ram Makena, Thinh H. Nguyen, Siddhartha Yavvari, Maninder Kaur, Teresia Pham, Eduardo Urias, Narendra Panapitiya, Mohamad M. Al-Rahawan. Sarcoma as second cancer in pediatric cancer survivors: Large population analysis [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 2299.

Abstract 1293: MYC transcription activation mediated by OCT4 as a mechanism of resistance to 13-cisRA-mediated differentiation in neuroblastoma

MYCN genomic amplification is one of the risk factors in neuroblastoma. 13-cis retinoic acid (13-cisRA), a differentiating agent, down-regulates MYCN protein and is part of neuroblastoma maintenance therapy. Despite the improvement in clinical outcome with 13-cisRA, anti-GD2 monoclonal antibody plus cytokine immunotherapy given in first response ~40% of high-risk neuroblastoma patients still die of recurrent disease. Although MYC genomic amplification is rare in neuroblastoma (~1%), 11% of neuroblastoma primary tumors collected at diagnosis (Dx) have high c-MYC protein suggesting that MYC transcriptional activation rather than its gene amplification drives such tumors. Here, we sought to investigate the role of MYC oncogene in progressive disease (PD) and to molecularly characterize mechanisms of MYC expression in neuroblastoma. We report transcriptional activation of MYC medicated by the OCT4 (encoded by POU5F1), functionally replacing MYCN in 13-cisRA-resistant progressive disease neuroblastoma. In large panels of neuroblastoma patient-derived cell lines (19 Dx and 16 PD) and patient-derived xenograft PDX models (8 Dx and 9 PD), we confirmed that c-MYC expression levels were higher in PD relative to Dx lines (P = 0.0005). We identified OCT4 and TCF3 as transcription factors highly expressed in neuroblastoma cells with high c-MYC. Subsequently, we confirmed two novel OCT4-binding sites (including OBS1 and OBS2) located in the MYC promoter/enhancer region: -1209 to -1140 and found that OCT4 NH2-terminal domain (NTD) and POU specific domain (POUs) are critical for MYC transcriptional activation. To identify kinases that is associated with OCT4-induced c-MYC activation, we used mass spectrometry and PhosphoMotif Finder® and identified MAPKAPK2 (MK2) as one of the upstream kinases that can bind to and directly regulate the OCT4 biological function by phosphorylation at its amino acid Ser111 residue to transcriptionally activate MYC expression. The data in 175 MYCN non-amplified high-risk primary tumors (TARGET database) showed that MAPKAPK2 positively correlated with MYC expression (P &lt; 0.001) and overall survival was lower (P &lt; 0.001) for patients with high MAPKAPK2. Also, OCT4, MK2, and c-MYC were higher in PD relative to Dx neuroblastomas models. Functional studies by gene knockdown of the POU5F1 or MAPKAPK2 using shRNAs showed decreased c-MYC expression, inhibition of cell proliferation, and restoring neurite outgrowth in response to 13-cisRA. In conclusion, high c-MYC independent of genomic amplification, not MYCN amplification, is associated with disease progression in neuroblastoma. The MK2-mediated OCT4 transcriptional activation is a novel mechanism for MYC activation in PD neuroblastoma and provides a potential novel therapeutic target.

Citation Format: Sung Jen Wei, Thinh H. Nguyen, Dustin G. Mook, Monish R. Makena, Dattesh Verlekar, Ashly Hindle, Gloria Martinez, Shengping Yang, Hiroyuki Shimada, C. Patrick Reynolds, Min H. Kang. MYC transcription activation mediated by OCT4 as a mechanism of resistance to 13-cisRA-mediated differentiation in neuroblastoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1293.

Telomere Maintenance Mechanisms Define Clinical Outcome in High-Risk Neuroblastoma

Neuroblastoma is a childhood cancer with heterogeneous clinical outcomes. To comprehensively assess the impact of telomere maintenance mechanism (TMM) on clinical outcomes in high-risk neuroblastoma, we integrated the C-circle assay [a marker for alternative lengthening of telomeres (ALT)], TERT mRNA expression by RNA-sequencing, whole-genome/exome sequencing, and clinical covariates in 134 neuroblastoma patient samples at diagnosis. In addition, we assessed TMM in neuroblastoma cell lines (n = 104) and patient-derived xenografts (n = 28). ALT was identified in 23.4% of high-risk neuroblastoma tumors and genomic alterations in ATRX were detected in 60% of ALT tumors; 40% of ALT tumors lacked genomic alterations in known ALT-associated genes. Patients with high-risk neuroblastoma were classified into three subgroups (TERT-high, ALT+, and TERT-low/non-ALT) based on presence of C-circles and TERT mRNA expression (above or below median TERT expression). Event-free survival was similar among TERT-high, ALT+, or TERT-low/non-ALT patients. However, overall survival (OS) for TERT-low/non-ALT patients was significantly higher relative to TERT-high or ALT patients (log-rank test; P < 0.01) independent of current clinical and molecular prognostic markers. Consistent with the observed higher OS in patients with TERT-low/non-ALT tumors, continuous shortening of telomeres and decreasing viability occurred in low TERT-expressing, non-ALT patient-derived high-risk neuroblastoma cell lines. These findings demonstrate that assaying TMM with TERT mRNA expression and C-circles provides precise stratification of high-risk neuroblastoma into three subgroups with substantially different OS: a previously undescribed TERT-low/non-ALT cohort with superior OS (even after relapse) and two cohorts of patients with poor survival that have distinct molecular therapeutic targets. SIGNIFICANCE: These findings assess telomere maintenance mechanisms with TERT mRNA and the ALT DNA biomarker C-circles to stratify neuroblastoma into three groups, with distinct overall survival independent of currently used clinical risk classifiers.

MYC transcription activation mediated by OCT4 as a mechanism of resistance to 13-cisRA-mediated differentiation in neuroblastoma

Despite the improvement in clinical outcome with 13-cis-retinoic acid (13-cisRA) + anti-GD2 antibody + cytokine immunotherapy given in first response ~40% of high-risk neuroblastoma patients die of recurrent disease. MYCN genomic amplification is a biomarker of aggressive tumors in the childhood cancer neuroblastoma. MYCN expression is downregulated by 13-cisRA, a differentiating agent that is a component of neuroblastoma therapy. Although MYC amplification is rare in neuroblastoma at diagnosis, we report transcriptional activation of MYC medicated by the transcription factor OCT4, functionally replacing MYCN in 13-cisRA-resistant progressive disease neuroblastoma in large panels of patient-derived cell lines and xenograft models. We identified novel OCT4-binding sites in the MYC promoter/enhancer region that regulated MYC expression via phosphorylation by MAPKAPK2 (MK2). OCT4 phosphorylation at the S111 residue by MK2 was upstream of MYC transcriptional activation. Expression of OCT4, MK2, and c-MYC was higher in progressive disease relative to pre-therapy neuroblastomas and was associated with inferior patient survival. OCT4 or MK2 knockdown decreased c-MYC expression and restored the sensitivity to 13-cisRA. In conclusion, we demonstrated that high c-MYC expression independent of genomic amplification is associated with disease progression in neuroblastoma. MK2-mediated OCT4 transcriptional activation is a novel mechanism for activating the MYC oncogene in progressive disease neuroblastoma that provides a therapeutic target.

Sarcoma as Second Cancer in a Childhood Cancer Survivor: Case Report, Large Population Analysis and Literature Review

The majority of pediatric patients are cured of their primary cancer with current advanced developments in pediatric cancer therapy. However, survivors often experience long-term complications from therapies for primary cancer. The delayed mortality rate has been decreasing with the effort to reduce the therapeutic exposure of patients with pediatric cancers. Our study investigates the incidence of sarcoma as second cancer in pediatric cancer survivors. We present a 9-year-old male who survived embryonal hepatoblastoma diagnosed at 22 months of age. At 4.5 years of age, he presented with a non-metastatic primitive neuroectodermal tumor (PNET) of the left submandibular area. He has no evidence of recurrence of either cancer for 51 months after finishing all chemotherapy and radiotherapy. We used the Surveillance, Epidemiology, and End Results (SEER) database to identify the current rate of second sarcomas in pediatric cancer survivors. Our literature review and large population analysis emphasize the impact of sarcoma as a second malignancy and provide help to physicians caring for pediatric cancer survivors.

Medicare for All: Considerations for Neuroradiologists

The year 2019 featured extensive debates on transforming the United States multipayer health care system into a single-payer system. At a time when reimbursement structures are in flux and potential changes in government may affect health care, it is important for neuroradiologists to remain informed on how emerging policies may impact their practices. The purpose of this article is to examine potential ramifications for neuroradiologist reimbursement with the Medicare for All legislative proposals. An institution-specific analysis is presented to illustrate general Medicare for All principles in discussing issues applicable to practices nationwide.

P813Iatrogenic takotsubo syndrome: incidence and impact

Background

Although Takotsubo syndrome (TTS) was once considered to be rare and largely benign, it is now recognised to represent a major cause of cardiac morbidity and mortality, especially in aging women. The biochemical precipitant of attacks of TTS is an increase in catecholamine concentrations within the myocardium, engendering inflammatory activation via biased post-receptor signalling at myocardial β2-adrenoceptor level. Cases of TTS have been reported in patients treated with catecholamines, and with antidepressants which limit catecholamine re-uptake. In the current investigation, we sought to delineate the extent and potential impact of this “iatrogenic” form of TTS.

Methods/Results

Patients' data from a regional registry of 272 consecutive cases of TTS were evaluated. After exclusion of patients (n=14) in whom TTS has occurred in association with life threatening extracardiac disease states, a total of 47 (18%) of patients were identified as having antecedent exposure to potentially “iatrogenic” agents (antidepressants in 29 cases, β2-adrenoceptor agonists in 14). Demographics, including proportion of male patients, did not differ significantly between patients with and without “iatrogenic” TTS, but plasma concentrations of the catecholamine metabolite normetanephrine tended to be greater (median 1160 vs. 950 pmol/L; p=0.07). Long-term survival (median follow-up 3.5 years) was marginally (p=0.09) worse for patients with “iatrogenic” TTS.

Conclusion

(1) A potentially iatrogenic component of precipitation (via iatrogenic elevation of catecholamine levels and β2-adrenoceptor stimulation) is present in a substantial proportion of patients.

(2) In such patients there is an implication of increased long-term mortality risk, potentially accentuated by continued administration of the precipitating agent(s).

P6006Pathogenesis of symptomatic crises in patients with coronary artery spasm: evidence for acute damage to vascular glycocalyx and to circulating platelets

Background

Coronary artery spasm (CAS) is known to occur commonly even in a “pure culture”, but little is known regarding the precipitation of the symptomatic crises which characterize this disorder. There have been recent reports of the occurrence of plaque erosion and intracoronary thrombosis during CAS crises. We have recently shown that (1) the anti-aggregatory effects of nitric oxide (NO) are impaired in CAS patient and (2) release into plasma of the endothelial glycocalyx component syndecan-1 (SD-1) occurs during acute episodes of CAS, suggesting glycocalyx erosion by inflammatory enzyme release.

Objective

In the current study, we sought to determine whether this phenomenon is accompanied by damage to circulating platelets and whether activation of mast cells may represent a possible precipitant.

Methods

In patients with acute episodes and chronic phases of CAS (n=10), as well as normal subjects (n=12), plasma concentrations of SD-1, of platelet-derived microparticles (PMPs), of the mast cell enzyme tryptase and of malondialdehyde (MDA), a measure of oxidative stress, were evaluated.

Results

The results are summarized in the table. Symptomatic crises were associated with substantial elevation of SD-1 concentrations and also those of PMPs and of tryptase, relative to chronic status. However, MDA concentrations did not vary significantly during acute episodes.

Impact of acute exacerbation of CAS on markers of glycocalyx shedding (SD-1), platelet activation (PMP counts), mast cell activation (tryptase) and oxidative stress (MDA) Parameter Acute CAS Chronic CAS p* Normal subjects** SD-1 (μg/L) 50.3±3.9 14.3±4.7 <0.0001 12.7±2.4 PMPs (counts) 24200±8100 4800±1010 0.02 10400±2900 Tryptase (μg/L) 4.4±0.4 4.1±0.4 0.03 <12.0 MDA (μM) 3.2±0.2 3.1±0.1 NS 3.09±0.15 *Acute vs. chronic; **provided for reference only.

Conclusion

(1) The combination of SD-1 release and formation of PMPs suggests that CAS crises reflect both glycocalyx “shedding” and platelet activation/apoptosis, a combination which would facilitate coronary thrombosis.

(2) CAS crises are associated with mast cell activation, which may contribute to the above vascular/platelet damage.

P6003Coronary artery spasm: a consequence of impaired nitric oxide/hydrogen sulphide signalling?

Background

Coronary artery spasm (CAS) represents a major cause of patient morbidity, with variable clinical response to prophylaxis with calcium antagonists and generally poor symptomatic relief with organic nitrates. The precipitation of CAS with acetylcholine may reflect impaired nitric oxide (NO) release and/or signalling. We have recently demonstrated that platelets from patients with CAS exhibit markedly impaired anti-aggregatory responses to the NO donor sodium nitroprusside (SNP) (“NO resistance”).

Purpose

In the current experiments we sought to determine whether N-acetylcysteine (NAC), which is known to potentiate haemodynamic responses to organic nitrates, reverses NO resistance in platelets from CAS patients.

Methods

Patients with CAS were studied during acute (n=11) and chronic (n=24) phases of symptoms. NAC (10 g/24 hours) was infused together with low dose NTG (2.5 μg/min) in patients presenting with acute exacerbations, and platelets were studied ex vivo. In blood samples taken from chronic CAS patients, in vitro studies were performed to evaluate the possible role of H2S release (via cysteine formation) from NAC in putative potentiation of NO effect.

Results

(1) In acute patients, NTG/NAC infusion resulted in increases in platelet response to SNP (p=0.003);

(2) In vitro studies showed that incubation with NAC or the H2S donor NaHS potentiated SNP responses (Figure 1A);

(3) Effects of NAC were reversed by co-incubation with aminooxyacetic acid (AOAA) and D, L-propargylglycine (PAG), inhibitors of enzymatic cysteine bioconversion to release H2S (Figure 1B).

Figure 1

Conclusion

CAS-associated impairment of platelet NO signaling reflects a deficiency of the H2S/NO interaction, and can be reversed using exogenous H2S donors, including NAC.

Cytotoxic activity of difluoromethylornithine compared with fenretinide in neuroblastoma cell lines

BACKGROUND

Maintenance therapy with 13-cis-retinoic acid and immunotherapy (given after completion of intensive cytotoxic therapy) improves outcome for high-risk neuroblastoma patients. The synthetic retinoid fenretinide (4-HPR) achieved multiple complete responses in relapse/refractory neuroblastoma in early-phase clinical trials, has low systemic toxicity, and has been considered for maintenance therapy clinical trials. Difluoromethylornithine (DFMO, an irreversible inhibitor of ornithine decarboxylase with minimal single-agent clinical response data) is being used for maintenance therapy of neuroblastoma. We evaluated the cytotoxic activity of DFMO and fenretinide in neuroblastoma cell lines.

PROCEDURE

We tested 16 neuroblastoma cell lines in bone marrow-level hypoxia (5% O₂ ) using the DIMSCAN cytotoxicity assay. Polyamines were measured by HPLC-mass spectrometry and apoptosis by transferase dUTP nick end labeling (TUNEL) using flow cytometry.

RESULTS

At clinically achievable levels (100 μM), DFMO significantly decreased (P < 0.05) polyamine putrescine and achieved modest cytotoxicity (<1 log (90% cytotoxicity). Prolonged exposures (7 days) or culture in 2% and 20% O₂ did not enhance DFMO cytotoxicity. However, fenretinide (10 μM) even at a concentration lower than clinically achievable in neuroblastoma patients (20 μM) induced ≥ 1 log cell kill in 14 cell lines. The average IC₉₀ and IC₉₉ of fenretinide was 4.7 ± 1 μM and 9.9 ± 1.8 μM, respectively. DFMO did not induce a significant increase (P > 0.05) in apoptosis (TUNEL assay). Apoptosis by fenretinide was significantly higher (P < 0.001) compared with DFMO or controls.

CONCLUSIONS

DFMO as a single agent has minimal cytotoxic activity for neuroblastoma cell lines.

Von Hippel-Lindau with early onset of hemangioblastoma and multiple drop-metastases like spinal lesions: A case report

RATIONALE

Hemangioblastoma is a rare tumor of the central nervous system (CNS). It is usually observed in patients with von-Hippel Lindau (VHL). The peak age for hemangioblastoma is between 20 and 50 years of age with very few cases over 65 or below 18 years of age.

PATIENT CONCERNS

We report a female with a rare VHL mutation (c.337C>T) who was diagnosed with multifocal CNS hemangioblastoma at a very young age.

DIAGNOSIS

At 17-years of age, she presented with obstructive hydrocephalus due to large cystic cerebellar mass. Imaging showed multiple lesions resembling drop metastases throughout her spinal cord. Immunohistochemistry of the resected tumor confirmed the pathological diagnosis of hemangioblastoma (World Health Organization Grade 1).

INTERVENTIONS AND OUTCOME

She was treated with multi-stage resection of her primary and drop- metastasis like disease. She presented six months later with retinal hemangioblastoma while her other lesions were stable. She presented with multiple CNS and eye hemangioblastomas after failing to follow up for 2 years. Subsequently, Everolimus was started to treat her systemic disease.

LESSONS

The unique feature of our case is the presence of multiple drop-metastases like spinal lesions, which has not been reported in the literature to be associated with hemangioblastoma.

Abstract 4812: Vorinostat and fenretinide synergize in preclinical models of T-cell lymphoid malignancies via reactive oxygen species

Introduction: T-cell lymphoid malignancies (TCLMs) are in need of novel and more effective therapies. Pan-histone deacetylase (HDAC) inhibitors vorinostat and belinostat, and class I specific HDAC inhibitor romidepsin have achieved FDA registration as 2nd line therapies for peripheral and/or cutaneous T-cell lymphomas. The cytotoxic retinoid fenretinide achieved durable complete responses against T-cell lymphomas in early-phase clinical trials and T-cell lymphoma patients who failed prior HDAC inhibitor treatment responded to fenretinide (Clinical Cancer Res 23:4550-4555, 2017). Fenretinide is currently being evaluated in a Phase IIa clinical trial for relapsed/refractory PTCL patients (NCT02495415). We have previously shown romidepsin and fenretinide synergize in preclinical models of T-cell lymphoid malignancies (Molecular Cancer Therapeutics 16:649-661, 2017). There exist some key differences in the activity of various classes of HDAC's, which have significantly different chemical structures and metabolic profiles. Therefore we determined if the pan-HDAC inhibitor vorinostat synergizes with fenretinide.

Methods and Results: Using the DIMSCAN cytotoxicity assay, we demonstrated cytotoxic synergy between vorinostat and fenretinide in nine TCLM cell lines at clinically-achievable concentrations that lacked cytotoxicity for non-malignant cells (fibroblasts and blood mononuclear cells). In vivo, vorinostat + fenretinide + ketoconazole (enhances fenretinide exposures by inhibiting fenretinide metabolism) showed greater activity in subcutaneous (COG-LL-317m and TX-LY-183x PDX) TCLM xenograft models than single agent vorinostat or fenretinide + ketoconazole. Fenretinide + vorinostat caused a reactive oxygen species (ROS, measured by DCFDA dye)-dependent increase in apoptosis (via TUNEL assay), and histone acetylation (measured by immunoblotting). The synergistic cytotoxicity, apoptosis, and histone acetylation of fenretinide + vorinostat was abrogated by antioxidant vitamin C. Vorinostat + fenretinide activated p38 and JNK via ROS, and shRNA knockdown of p38 and JNK1 significantly decreased the synergistic cytotoxicity and apoptosis. Vorinostat + fenretinide also showed synergistic cytotoxicity for six B-lymphoid malignancy cell lines.

Conclusion: Like romidepsin, vorinostat combined with fenretinide achieved synergistic activity in preclinical models of TCLMs, but not in non-malignant cells, via a novel molecular mechanism. As vorinostat is an oral agent and not a PGP substrate it may have advantages in such combination therapy. These data support conducting a clinical trial of vorinostat combined with fenretinide in relapsed and refractory TCLMs.

Citation Format: Monish Ram Makena, Thinh H. Nguyen, Balakrishna Koneru, Ashly Hindle, Wan-Hsi Chen, Dattesh U. Verlekar, Min H. Kang, C. Patrick Reynolds. Vorinostat and fenretinide synergize in preclinical models of T-cell lymphoid malignancies via reactive oxygen species [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4812.

Botulinum neurotoxin injection for the treatment of epiphora in nasolacrimal duct obstruction

PURPOSE

Retrospective long-term study to evaluate the efficacy of botulinum neurotoxin A (BoNT/A) therapy for epiphora due to non-surgical nasolacrimal duct obstruction.

INTRODUCTION

BoNT/A has been used successfully since 2000 in axillary hyperhidrosis to reduce secretory disorders. Some isolated cases of hyperlacrimation or crocodile tear syndrome have been treated on this basis. We used BoNT/A to decrease lacrimal secretion in cases of epiphora.

METHODS

We reviewed the qualitative and quantitative degree of improvement of epiphora after botulinum neurotoxin injections in the palpebral lobe of the lacrimal gland, carried out in an ophthalmic centre between 2009 and 2016. Epiphora was graded using a questionnaire, Munk scores and Schirmer tests before and after injections. Severity of side effects was recorded.

RESULTS

Twenty-seven palpebral lacrimal glands of twenty patients with epiphora, mean age 65±13, were treated with BoNT/A (Botox^® or Xeomin^®) from April 2009 to April 2016. The epiphora was induced by persistent nasolacrimal duct stenosis after surgical treatment. No conventional medical nor surgical treatment was effective at this time. The technique of injection, dilution and dosage were specific. We re-injected 14/27 cases on an as-needed basis, 7/27 cases three times, 3/27 cases four times, and 2/27 cases (same patient both glands) five times. The Schirmer test measured a decrease of lacrimal secretion in 24/27 (89%) lacrimal glands after neurotoxin injection. Side effects were ptosis in 4 cases and transient esotropia in 2 cases. The authors describe the injection techniques, the dosage, the volume and concentration of BoNT/A.

CONCLUSION

Patients with epiphora can be treated effectively with BoNT/A to reduce lacrimal secretion of the principal lacrimal gland in its palpebral portion. Ninety percent of the patients were very satisfied, with few side effects (ptosis or mild diplopia lasting from 3 days to 3 weeks). More studies are needed to delineate which types of epiphora can be treated with BoNT/A.

Characterization and Applications of Marine Microbial Enzymes in Biotechnology and Probiotics for Animal Health

Marine microorganisms have been recognized as potential sources of novel enzymes because they are relatively more stable than the corresponding enzymes derived from plants and animals. Enzymes from marine microorganisms also differ from homologous enzymes in terrestrial microorganisms based on salinity, pressure, temperature, and lighting conditions. Marine microbial enzymes can be used in diverse industrial applications. This chapter will focus on the biotechnological applications of marine enzymes and also their use as a tool of marine probiotics to improve host digestion (food digestion, food absorption, and mucus utilization) and cleave molecular signals involved in quorum sensing in pathogens to control disease in aquaculture.

Species composition and level of infestation of cockroaches in three areas in Hanoi

A study on the species composition and the level of infestation of cockroaches was carried out from April 2013 to October 2014 in three localities of Hanoi, Vietnam, namely the Lan Ong-Old Town, Linh Dam condominium and Tan Da Resort. Out of the 187 units of premises examined, 44.9% of units were infested with cockroaches. A total of 576 cockroaches were trapped, of which six species were identified: Periplaneta americana (L.) was the most dominant species (72.1%), followed by Blattella germanica (L.) (14.8%), Pycnoscelus surinamensis (L.) (7.3%), Periplaneta australasiae (Fabricius) (2.9%), Periplaneta fuliginosa (Serville) (1.9%) and Supella longipalpa (Fabricius) (1.0%). Infestation was the highest in Lan Ong (74.0%), followed by Linh Dam (40.5%) and Tan Da (25.9%). Cockroaches were abundantly found in warehouses (100%), electrical distribution room (56.3%), and kitchens (46.7%).

Liver regeneration following repeated reversible portal vein embolization in an experimental model

BACKGROUND

Portal vein embolization (PVE) is used routinely to prevent postoperative liver failure as a result of anticipated insufficient future liver remnant volume following resection. The authors have recently developed a technique for temporary PVE. The aim of this study was to assess the effect of repeated reversible PVE on hepatocyte proliferation and subsequent liver hypertrophy in rodents.

METHODS

Four treatments were compared (n = 21 rats per group): single reversible PVE, two PVEs separated by 14 days, partial portal vein ligation or sham procedure. The feasibility and tolerance of the procedure were assessed. Volumetric imaging by CT was used to estimate the evolution of liver volumes. After death, the weight of liver lobes was measured and hepatocyte proliferation evaluated by immunostaining.

RESULTS

Embolization of portal branches corresponding to 70 per cent of total portal flow was performed successfully in all animals. Repeated PVE induced additional hepatocyte proliferation. Repeated embolization resulted in superior hepatocyte proliferation in the non-occluded segments compared with portal vein ligation (31·1 versus 22·2 per cent; P = 0·003). The non-occluded to total liver volume ratio was higher in the repeated PVE group than in the single PVE and sham groups (P = 0·050 and P = 0·001 respectively).

CONCLUSION

Repeated reversible PVE successfully induced additional hepatocyte proliferation and subsequent liver hypertrophy. Surgical relevance Portal vein embolization (PVE) is used routinely to prevent postoperative liver failure as a result of anticipated insufficient future liver remnant volume following resection. In the present study, a technique of repeated temporary PVE was developed in a rat model; this induced additional hepatocyte proliferation and an increase in liver volume compared with single embolization. This novel approach might help induce major hypertrophy of the future remnant liver, which could increase the rate of patients amenable to major liver resections.

Antinociceptive activity of the new triple reuptake inhibitor NS18283 in a mouse model of chemotherapy-induced neuropathic pain

BACKGROUND

Chronic neuropathic pain can lead to anxiety and depression. Drugs that block reuptake of serotonin, norepinephrine and/or dopamine are widely used to treat depression, and have emerged as useful drugs in the treatment of neuropathic pain. This study compared the acute antinociceptive effects of NS18283, a novel triple monoamine reuptake inhibitor (MRI) with indatraline, venlafaxine and escitalopram in a mouse model of neuropathic pain.

METHOD

Neuropathic pain-like behaviours were induced in mice by repeated injections of oxaliplatin (OXA), and assessed using the von Frey hair test, the cold plate test and the thermal preference plate test. Anxio/depressive phenotype and antidepressant-like properties of compounds were assessed by the novelty suppressed feeding test and the tail suspension test, respectively.

RESULTS

In vivo microdialysis experiments showed that each MRI increased extracellular serotonin, norepinephrine and/or dopamine levels in the cingulate cortex, in agreement with their in vitro reuptake inhibitory properties. Indatraline (3 mg/kg) reversed the full repertoire of OXA-induced neuropathic hypersensitivity. NS18283 (10 mg/kg) reversed OXA-induced mechano-hypersensitivity and cold allodynia. Venlafaxine (16 mg/kg) and escitalopram (4 mg/kg) only reversed cold allodynia and mechano-hypersensitivity, respectively. All MRIs produced antidepressant-like activity in anxio/depressive phenotype of OXA mice.

CONCLUSIONS

Acute administration of drugs that enhance the activity of serotonin, norepinephrine and dopamine neurotransmission within nociceptive pathways may provide a broader spectrum of antinociception than dual or selective reuptake inhibitors in animal models of neuropathic pain. Whether similar observations would occur after repeated administration of such compounds in an attempt to simulate dosing in humans, or be compromised by dopaminergic-mediated adverse effects warrants further investigation.

Common isolation of New Delhi metallo-beta-lactamase 1-producing Enterobacteriaceae in a large surgical hospital in Vietnam

This study sought to monitor the presence of carbapenem-resistant Enterobacteriaceae (CRE) and the proportion New Delhi metallo-beta-lactamase 1 (NDM-1)-producing bacteria between August 2010 and December 2012 in a surgical hospital in Vietnam. We identified 47 CRE strains from a total of 4,096 Enterobacteriaceae isolates (1.1 %) that were NDM-1-positive from 45 patients admitted to 11 different departments, with the majority being from the urology department. The NDM-1 gene was found in seven different species. Genotyping revealed limited clonality of NDM-1-positive isolates. Most of the isolates carried the NDM-1 gene on a plasmid and 17.8 % (8/45) of those were readily transferable. We found five patients at admission and one patient at discharge with NDM-1-positive bacteria in their stool. From 200 screening environmental hospital samples, five were confirmed to be NDM-1-positive and included Acinetobacter species (n = 3) and Enterobacter aerogenes (n = 2). The results reveal that NDM-1-producing Enterobacteriaceae are commonly isolated in patients admitted to a Vietnamese surgical hospital and are also detected in the hospital environment.

Antibody landscapes after influenza virus infection or vaccination

We introduce the antibody landscape, a method for the quantitative analysis of antibody-mediated immunity to antigenically variable pathogens, achieved by accounting for antigenic variation among pathogen strains. We generated antibody landscapes to study immune profiles covering 43 years of influenza A/H3N2 virus evolution for 69 individuals monitored for infection over 6 years and for 225 individuals pre- and postvaccination. Upon infection and vaccination, titers increased broadly, including previously encountered viruses far beyond the extent of cross-reactivity observed after a primary infection. We explored implications for vaccination and found that the use of an antigenically advanced virus had the dual benefit of inducing antibodies against both advanced and previous antigenic clusters. These results indicate that preemptive vaccine updates may improve influenza vaccine efficacy in previously exposed individuals.

Quantitative phase imaging with partially coherent illumination

In this Letter, we formulate a mathematical model for predicting experimental outcomes in quantitative phase imaging (QPI) when the illumination field is partially spatially coherent. We derive formulae that apply to QPI and discuss expected results for two classes of QPI experiments: common path and traditional interferometry, under varying degrees of spatial coherence. In particular, our results describe the physical relationship between the spatial coherence of the illuminating field and the halo effect, which is well known in phase-contrast microscopy. We performed experiments relevant to this common situation and found that our theory is in excellent agreement with the data. With this new understanding of the effects of spatial coherence, our formulae offer an avenue for removing halo artifacts from phase images.

An intrauterine catch-up growth regimen increases food intake and post-natal growth in rats

Nutritional conditions during the intrauterine stage are an important developmental programming factor that can affect the growth and metabolic status during foetal development and permanently alter the phenotypes of newborn offspring and adults. This study was performed to examine the effects of intrauterine catch-up growth (IUCG) on food intake, post-natal body growth and the metabolic status of offspring and growing rats. Control pregnant rats were fed ad libitum during the entire gestation period. For the IUCG regimen, pregnant rats were fed 50% of the food of the controls from pregnancy days 4 through 11 (8 days), followed by ad libitum feeding from pregnancy days 12 through parturition. The birth weight of offspring was not affected by the IUCG regimen. At weaning, offspring from each treatment group were assigned to two groups and given either a normal diet or high-fat diet (HFD) for 12 weeks until 103 days of age. In the normal diet group, the IUCG offspring showed a 9.0% increase (P < 0.05) in total food intake, were 11.2% heavier (p < 0.05) at 103 days of age and had an 11.0% greater (p < 0.05) daily weight gain compared with control offspring. The IUCG regimen did not affect body glucose and lipid metabolism. After exposure to the HFD, the IUCG regimen has not exacerbated metabolic disorders. In conclusion, our findings suggest that the IUCG nutritional regimen during pregnancy can increase the food intake and post-natal body growth of offspring without inducing metabolic disorders such as obesity and insulin resistance. The IUCG nutritional regimen might be used to improve the food intake and post-natal body growth of domestic animals.

Wnt/β-catenin signaling and adipogenic genes are associated with intramuscular fat content in the longissimus dorsi muscle of Korean cattle

Intramuscular fat (IMF) is an important trait that influences beef quality. In two studies, we examined the possible involvement of the Wnt/β-catenin signaling pathway in IMF deposition in Korean cattle. In study 1, using a group of bulls and steers, we found that castration, a non-genetic factor, decreased (P < 0.01) the expression of both the WNT10B and CTNNB1 genes, whereas it increased the expression of the Wnt antagonist secreted frizzled-related proteins 4 (SFRP4, P < 0.001) and the adipogenic CCAAT/enhancer binding protein (C/EPB), alpha (CEBPA, P < 0.001) and peroxisome proliferator-activated receptor gamma (PPARG, P < 0.05) genes in longissimus dorsi muscle (LM) tissue. The WNT10B and CTNNB1 mRNA levels showed strong (P < 0.001) negative correlations (r = -0.68 and r = -0.73 respectively) with the IMF content, whereas the SFRP4, CEBPA and PPARG mRNA levels showed strong (P < 0.01) positive correlations (r = 0.70, 0.70 and 0.64 respectively) with the IMF content. Large variation still exists in the IMF content of steers, implying that genetic factors affect IMF deposition. Using a different group of steers, a correlation analysis in study 2 also showed that the expression of the WNT10B and CTNNB1 genes, and SFRP4 and adipogenic genes was negatively and positively associated with the IMF content respectively. Our findings suggest that downregulation of the Wnt/β-catenin signaling pathway genes, but upregulation of Wnt antagonist SFRP4 and adipogenic gene expression following castration, contributes to increased IMF deposition in the LM. Our results demonstrate that both non-genetic factors (castration) and genetic variation within the steer group affect the gene expression pattern of the Wnt/β-catenin signaling pathway.

Abstract P2-05-22: Preferential Activation of BP1 and c-Myc in Breast Cancer of African American Women Compared with Caucasian American Women

Introduction: BP1 is a member of the homeobox gene family of transcription factors. BP1 is activated in 80% of breast tumors, including 89% of the tumors of African American women (AAW) compared with 57% of the tumors of Caucasian American women (CAW). AAW with breast cancer have larger tumors and an almost 50% higher mortality rate than CAW. BP1 expression is also associated with larger and more aggressive tumors, suggesting BP1 may contribute to the aggressiveness of tumors of AAW. Our goal is to identify molecular pathways underlying the discrepancy of breast cancer aggressiveness in AAW and CAW with particular attention to BP1 regulated pathways.

Materials and Methods: Gene expression analysis using RNA from cell lines derived from tumors of AAW or CAW was performed using Illumina microarrays. Changes in c-Myc mRNA were measured by real-time PCR and levels of c-Myc protein by immunoblotting. Knock down of c-Myc and BP1 expression was performed using their respective siRNA. Chromatin immunoprecipation (ChIP) analysis was used to determine potential BP1 and c-Myc binding sites in vivo. Immunohistochemistry was performed using a commercial rabbit polyclonal antibody to c-Myc and a rabbit polyclonal antibody to BP1 developed by the laboratory of one of the authors (PB).

Results: To study differential gene expression related to racial disparities and BP1 expression, we used breast cancer cell lines derived from tumors of AAW and cell lines derived from tumors of CAW. Microarray analysis was performed on three cell lines from AAW and two cell lines from CAW. The oncogene c-Myc was overly represented in the cell lines derived from AAW compared to their CAW derived counterparts; these cell lines also overexpress BP1. The data was verified by real-time PCR and Western blot analysis. Knock down of BP1 and c-Myc in separate experiments using siRNA showed a significant decrease of BP1 protein and c-Myc protein, respectively. ChIP analysis revealed binding of BP1 protein to DNA upstream of the c-Myc gene and of BP1 DNA by c-Myc protein, suggesting reciprocal activation.

Clinical studies. Age and stage matched cases of ductal breast cancers from AAW (n = 15) and CAW (n = 15) were immunostained and evaluated for nuclear c-Myc and nuclear BP1. In CAW, there was a linear correlation between BP1 and c-Myc staining. However, in AAW there was not a linear correlation due to extensive variability in individual results.

Conclusions: c-Myc is a potent oncogene known to increase transformation and proliferation. We show here that c-Myc is upregulated by BP1, a gene which is preferentially activated in breast tumors of AAW. Furthermore, we have identified an interesting mechanism by which BP1 and c-Myc may co-activate transcription involving a positive feedback loop, an attractive therapeutic target. The proposed mechanism could partially explain the aggressiveness of tumors of AAW.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-05-22.

The associative and limbic thalamus in the pathophysiology of obsessive-compulsive disorder: an experimental study in the monkey

Obsessive-compulsive disorder (OCD) is a frequent psychiatric disorder characterized by repetitive intrusive thoughts and severe anxiety, leading to compulsive behaviors. Although medical treatment is effective in most cases, resistance is observed in about 30% of patients. In this context, deep brain stimulation (DBS) of the caudate or subthalamic nuclei has been recently proposed with encouraging results. However, some patients were unimproved or exhibited awkward side effects. Therefore, exploration of new targets for DBS remains critical in OCD. In the latter, functional imaging studies revealed overactivity in the limbic and associative cortico-subcortical loops encompassing the thalamus. However, the role of the thalamus in the genesis of repetitive behaviors and related anxiety is unknown. Here, we tested the hypothesis that pharmacological-induced overactivity of the medial thalamus could give rise to abnormal behaviors close to that observed in OCD. We modulated the ventral anterior (VA) and medial dorsal (MD) nuclei activity by in situ bicuculline (GABA(A) antagonist) microinjections in subhuman primates and assessed their pharmacological-induced behavior. Bicuculline injections within the VA caused significant repetitive and time-consuming motor acts whereas those performed within the MD induced symptoms of dysautonomic dysregulation along with abnormal vocalizations and marked motor hypoactivity. These findings suggest that overactivation of the VA and MD nuclei of the thalamus provokes compulsive-like behaviors and neurovegetative manifestations usually associated with the feeling of anxiety in OCD patients. In further research, this translational approach should allow us to test the effectiveness and side effects of these thalamic nuclei DBS in monkey and perhaps, in a second step, to propose a transfer of this technique to severely disabled OCD patients.

Quantitative assessment of macrophages in the muscularis externa of mouse intestines

Quantification of intestinal cells is challenging for several reasons: The cell densities vary throughout the intestines and may be age dependent. Some cell types are ramified and/or can change shape and size. Additionally, immunolabeling is needed for the correct identification of cell type. Immunolabeling is dependent on both up- and down-regulation of the antigen being labeled as well as on the primary and secondary antibodies, the fixation, and the enhancement procedures. Here, we provide a detailed description of immunolabeling of CD169(+) cells and major histocompatibility class II antigen (MHCII(+) ) cells and the subsequent quantification of these cells using design-based stereology in the intestinal muscularis externa. We used young (5-weeks-old) and adult (10-weeks-old) mice. Cell densities were higher in jejunum-ileum, when compared with colon. In jejunum/ileum, the cell densities increased in oral-anal direction in adults, whereas the densities were highest in the midpart in young animals. In colon, the cell densities decreased in oral-anal direction in both groups of animals. Except for the density of MHCII(+) cells in colon, the cell densities were highest in young animals. Densities of CD169(+) and MHCII(+) cells did not differ, except in the colon of young animals where the CD169(+) density was almost twice as high as the MHCII(+) density. CD169 and MHCII antigens seem to be expressed simultaneously by the same cell in jejunum/ileum. We conclude that cell densities depend on both the age of the mouse and on the location in the intestines.

IC261 induces cell cycle arrest and apoptosis of human cancer cells via CK1δ/ɛ and Wnt/β-catenin independent inhibition of mitotic spindle formation

Casein kinase 1 delta and epsilon (CK1δ/ɛ) are key regulators of diverse cellular growth and survival processes including Wnt signaling, DNA repair and circadian rhythms. Recent studies suggest that they have an important role in oncogenesis. RNA interference screens identified CK1ɛ as a pro-survival factor in cancer cells in vitro and the CK1δ/ɛ-specific inhibitor IC261 is remarkably effective at selective, synthetic lethal killing of cancer cells. The recent development of the nanomolar CK1δ/ɛ-selective inhibitor, PF670462 (PF670) and the CK1ɛ-selective inhibitor PF4800567 (PF480) offers an opportunity to further test the role of CK1δ/ɛ in cancer. Unexpectedly, and unlike IC261, PF670 and PF480 were unable to induce cancer cell death. PF670 is a potent inhibitor of CK1δ/ɛ in cells; nanomolar concentrations are sufficient to inhibit CK1δ/ɛ activity as measured by repression of intramolecular autophosphorylation, phosphorylation of disheveled2 proteins and Wnt/β-catenin signaling. Likewise, small interfering RNA knockdown of CK1δ and CK1ɛ reduced Wnt/β-catenin signaling without affecting cell viability, further suggesting that CK1δ/ɛ inhibition may not be relevant to the IC261-induced cell death. Thus, while PF670 is a potent inhibitor of Wnt signaling, it only modestly inhibits cell proliferation. In contrast, while sub-micromolar concentrations of IC261 neither inhibited CK1δ/ɛ kinase activity nor blocked Wnt/β-catenin signaling in cancer cells, it caused a rapid induction of prometaphase arrest and subsequent apoptosis in multiple cancer cell lines. In a stepwise transformation model, IC261-induced killing required both overactive Ras and inactive p53. IC261 binds to tubulin with an affinity similar to colchicine and is a potent inhibitor of microtubule polymerization. This activity accounts for many of the diverse biological effects of IC261 and, most importantly, for its selective cancer cell killing.

Coulomb energy determination of a single Si dangling bond

Determination of the Coulomb energy of single point defects is essential because changing their charge state critically affects the properties of materials. Based on a novel approach that allows us to simultaneously identify a point defect and to monitor the occupation probability of its electronic state, we unambiguously measure the charging energy of a single Si dangling bond with tunneling spectroscopy. Comparing the experimental result with tight-binding calculations highlights the importance of the particular surrounding of the localized state on the effective charging energy.