Abstract 6029: Multi-omic landscape of squamous cell lung cancer

Patients with squamous cell lung cancer (SCC) have high unmet medical need. Knowledge of these tumors is limited, and a lack of targetable genomic drivers means patients have few treatment options. To provide a detailed analysis on the influence of genomic alterations to proteome-level changes in SCC, we previously integrated DNA copy number, somatic mutations, RNA-sequencing, and expression proteomics in a cohort of 108 SCC patients. A major finding was identification of three proteomic subtypes, two of which made up the majority (87%) of tumors: the “Inflamed” subtype was enriched for B-cell rich tertiary lymphoid structures (TLS), and the “Redox” subtype was enriched for redox pathways and NFE2L2/KEAP1 alterations but had significantly less immune infiltration. We hypothesized these proteomic subtypes would give rise to distinct metabolic signatures. Therefore, we performed untargeted metabolomics on 87 tumors from the same cohort using chromatographic separation on a HILIC column, followed by analysis on a Q Exactive HF mass spectrometer. This analysis yielded 7,344 features corresponding to 7,072 unannotated metabolites and 272 identified metabolites. Glutathione, a key redox metabolite, was anticorrelated with immune score (R = -0.44, padj = 0.004) calculated from our transcriptomic data with the ESTIMATE algorithm, and glutathione was elevated in the Redox proteomic subtype (0.58 log2 ratio, padj = 9.87E-04). Consensus clustering was next used to identify novel metabolomic subtypes of SCC. Surprisingly, none of the five metabolomic subtypes we identified corresponded to proteomic subtype or NFE2L2/KEAP1 alteration (Fisher’s Exact test p-values > 0.05). The fifth subtype had 332 metabolites (26 identified) differentially expressed (> 1.5 fold-change, padj < 0.05) with ascorbate and aldarate metabolism as the top enriched pathway (padj = 3.36E-04). Interestingly, this fifth metabolomic subtype had significantly higher DNp63-alpha (p = 2.40E-05), a primary transcript of delta-N p63 that is known to promote non-small cell lung cancer. Ongoing integrative analyses across omic types will determine how p53, p63, and p73 transcripts influence these metabolomic subtypes, how these transcripts relate to the poor immune infiltration in some SCC tumors, and if these transcripts relate to novel metabolic vulnerabilities in SCC.

Citation Format: Paul Stewart, Ashley Lui, Eric Welsh, Dalia Ercan, Vanessa Rubio, Hayley Ackerman, Guohui Li, Bin Fang, Steven Eschrich, John Koomen, Elsa Flores, Eric Haura, Gina DeNicola. Multi-omic landscape of squamous cell lung cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 6029.

Inducing a topological transition in graphene nanoribbon superlattices by external strain

Armchair graphene nanoribbons, when forming a superlattice, can be classified into different topological phases, with or without edge states. By means of tight-binding and classical molecular dynamics (MD) simulations, we studied the electronic and mechanical properties of some of these superlattices. MD shows that fracture in modulated superlattices is brittle, as for unmodulated ribbons, and occurs at the thinner regions, with staggered superlattices achieving a larger fracture strain than inline superlattices. We found a general mechanism to induce a topological transition with strain, related to the electronic properties of each segment of the superlattice, and by studying the sublattice polarization we were able to characterize the transition and the response of these states to the strain. For the cases studied in detail here, the topological transition occurred at ∼3-5% strain, well below the fracture strain. The topological states of the superlattice - if present - are robust to strain even close to fracture. The topological transition was characterized by means of the sublattice polarization of the states.

Diphenyl diselenide and cidofovir present anti-viral activity against Bovine Alphaherpesvirus 2 in vitro and in a sheep model

Bovine alphaherpesvirus 2 (BoHV-2) - the agent of bovine herpetic mamillitis (BHM) - is related to Human alphaherpesviruses 1 and 2 (HHV-1, HHV-2) and, as such, has been proposed as a model for vaccine and drug testing. We herein investigated the anti-viral activity in vitro against BoHV-2 of three anti-herpetic drugs: Cidofovir (CDV), Fanciclovir (FAM), Foscarnet (PFA), and diphenyl disselenide (Ph₂Se₂)_, a compound that has showed activity against HHV-2. Plaque reduction assays (PRA) revealed a significant reduction in viral plaques (p < 0.05) in cells treated with Ph₂Se₂ (79.7% reduction) or CDV (62.8%). FAM treatment resulted in a slight decrease in plaque number (22.9%, p < 0.05); PFA showed no activity. The effects of Ph₂Se₂ and CDV, alone or in combination, were investigated in ewes inoculated with BoHV-2 transdermally and submitted to daily topic treatment. Virus inoculated ewes developed lesions progressing through the stages of hyperemia, large papules or depressed dark areas, followed by scab formation. Treatment with Ph₂Se₂ resulted in reduction in clinical score from day 10 pi onwards (P < 0.05), shortening of clinical course and reduction in duration of virus shedding (P < 0.05) compared to untreated controls. Combined treatment (Ph₂Se₂ + CDV) and CDV alone, also led to clinical improvement (P < 0.05), yet less pronounced and delayed. These results are promising towards the use of Ph₂Se₂, alone or in combination with anti-herpetic drugs, in the treatment of udder and teat lesions produced by BoHV-2 in dairy cows.

p63 and Its Target Follistatin Maintain Salivary Gland Stem/Progenitor Cell Function through TGF-β/Activin Signaling

Multipotent ΔNp63-positive cells maintain all epithelial cell lineages of the embryonic and adult salivary gland (SG). However, the molecular mechanisms by which ΔNp63 regulates stem/progenitor (SP) cell populations in the SG remains elusive. To understand the role of ΔNp63 in directing cell fate choices in this gland, we have generated ΔNp63-deleted adult mice and primary salivary cell cultures to probe alterations in SP cell differentiation and function. In parallel, we have leveraged RNA-seq and ChIP-seq-based characterization of the ΔNp63-driven cistrome and scRNA-seq analysis to molecularly interrogate altered SG cellular identities and differentiation states dependent on ΔNp63. Our studies reveal that ablation of ΔNp63 results in a loss of the SP cell population and skewed differentiation that is mediated by Follistatin-dependent dysregulated TGF-β/Activin signaling. These findings offer new revelations into the SP cell gene regulatory networks that are likely to be relevant for normal or diseased SG states.

AB0593 DOES REALLY EXIST MIXED CONNECTIVE TISSUE DISEASE?

Background:

Currently, most authors accept that mixed connective tissue disease (MCTD) is an independent entity, although there are those who argue that it is actually an overlap syndrome or an undifferentiated early phase of another systemic autoimmune disease (SAD).

Objectives:

To analyze the long term evolution of a serie of patients with MCTD.

Methods:

Observational, retrospective and multicenter study in patients with MCTD (diagnostic criteria of Alarcón-Segovia et al),followed for a minimun of 2 years.

Results:

Fifty-five patients (49 women) with a median age at diagnosis of 38±14 years and with a follow up time (median) of 101 months (range, 24-237 months with a total of 501.2 pacients-year) were identified.

At the end of the follow-up period, only 27% (15/55) of the patients kept on fulfilling MCTD criteria. In the remaining 73% (40), 40% (22) had been differentiated to systemic lupus erythematosus (SLE), 13% (7) to systemic sclerosis (SSc) and 20% (11) developed an overlap syndrome [SSc+SLE in 8 cases and SSc+rheumatoid arthritis (AR) in 3]. In 8% of these patients, a secondary Sjögren’s syndrome was diagnosed during the follow-up period. The average score in patients who met the EULAR/ACR 2013 criteria for SSc was 11 (minimum 9 - maximum 16) and the average time elapsed from the diagnosis of MCTD to meet SSc criteria was 64.4 months (interquartile range [IQR] 25-75%: 10-127 months).

Applying the 2012 SLICC criteria, only 24 patients of those initially diagnosed as MCTD ended up meeting SLE criteria. The average score in these patients was 5.6 (4-9) and the average time elapsed from the diagnosis of MCTD unltil fulfilling the SLICC criteria was 39 months (IQR 25-75%: 6-28). When we apply the new ACR/EULAR 2019 criteria, the percentage of patients who meet SLE criteria increased to 30%, with an average score of 17.3 (10-38). The average time elapsed since the diagnosis of MCTD until meeting the new SLE criteria was reduced to 17 months (IQR 25-75: 0-10).

In the multivariate study, the presence of sclerodactyly (OR: 2.91; IC 95% 1.90 - 4.1, p= 0.001) and esophageal involvement (OR: 2.05; IC 95% 1.14–3.66, p=0.016) were associated with the evolution to SSc. Any predictor of evolution to SLE was identified.

Conclusion:

Only slightly more than a quarter of patients initially diagnosed as MCTD maintain this diagnosis during the follow-up. The majority, ended up evolving towards to another SAD, fundamentally SLE and SSc. The new ACR/EULAR 2019 criteria seems to be more sensitive than the SLICC 2012 criteria for diagnose SLE in these patients.

Disclosure of Interests:

L Montolio-Chiva: None declared, J. Narváez: None declared, Maria Pascual: None declared, Hye Sang Park: None declared, Ana V Orenes Vera: None declared, Eduardo Flores: None declared, Juanjo J Alegre-Sancho Consultant of: UCB, Roche, Sanofi, Boehringer, Celltrion, Paid instructor for: GSK, Speakers bureau: MSD, GSK, Lilly, Sanofi, Roche, UCB, Actelion, Pfizer, Abbvie, Novartis, Iván Castellví: None declared, Joan Miquel Nolla: None declared

AB0163 ANTI-KU ANTIBODIES: MUCH MORE THAN SCLEROMYOSITIS

Background:

Initially, anti-Ku antibodies (Ab) were described in patients with overlap syndrome with systemic sclerosis (SSc) and inflammatory myophaty (scleromyositis), although later they have been linked to a wide variety of systemic autoimmune diseases (SAD) questioning its diagnostic value. Recently, the possible existence of 2 different clinical phenotypes associated with these Ab has been described: one with myositis and high risk of intersticial lung disease (ILD) and another with positive anti-dsDNA Ab and glomerulonephritis.

Objectives:

To analyze the clinical relevance and the main diagnosis of a serie of patients with positive anti-Ku Ab.

Methods:

Descriptive observational study of patients with anti-Ku Ab in two third level hospitals between 2011 and 2019. Their determination was made at the criteria of the requesting physician.

Results:

Twenty-three patients (20 women) with a median age of 59 ± 14 years (range, 24-83) and a follow up time (median) of 37 months (1-208) were identified. The main clinical and analytical characteristics, as well as the final clinical diagnosis of these patients are shown in Table 1. In the cluster analysis we could not identify clinical phenotypes, perhaps because of the small sample size. Only 50% of patients with myositis developed ILD. Regarding the final diagnosis, only 1 patient (5%) was diagnosed of scleromyositis. Besides detecting them in patients with SSc (39%) and idiopathic inflammatory myopathy (9%), anti-Ku Ab were detected in other SAD, the most frequent were systemic lupus erythematosus, rheumatoid arthritis (RA) and overlap syndrome of SSc + RA.

Table 1.

Main clinical-analytical manifestations and final diagnosis of pacientes with anti-Ku Ab.

FINAL CLINICAL DIAGNOSiSScleromyositis: 1Idiopahtic inflammatory myopathy: 1Systemic sclerosis (SSc): 6 (Pre-scleroderma: 3, limited SSc: 3).Systemic lupus erythematosus: 2Rheumatoid arthritis: 2Overlap syndrome RA + limited SSc: 2Primary Sjögren’s syndrome: 1 (Secondary Sjögren’s syndrome: 3)Mixed connective tissue disease: 1Polymyalgia rheumatica: 1Undifferentiated connective tissue disease: 1Acute hepatitis due to HEV: 1Autoimmune thrombocytopenia (ITP): 1Drug-induced fibrosing ILD: 1Systemic graft versus host disease (GVHD) in a patient with acute lymphoblastic leukemia who received and autologous haematopoietic progenitor transplant: 1Primary biliary cirrhosis: 1CLINICAL MANIFESTATIONS(patients could have more than one):Raynaud’s phenomenon: 61% (14/23).Inflammatory arthralgia/arthritis: 52% (12).Lung involvement: 30.5% (7: NSIP 3, UIP 2, other patterns 2).Serositis: 26% (6: pericarditis 4, pleuritis 1, pleuropericarditis 1).Cardiac involvement: 26% (6: PHT by echocardiogram 3, myocarditis 2, arrhytmia 1).Dry syndrome: 17% (4)Myositis: 17% (4).Esophageal involvement: 17% (4).Autoimmune cytopenias: leucolinfopenia: 17% (4) / thrombocytopenia: 13% (3).Telangiectasias: 13% (3).Photosensitivity: 13% (3).Other: non-androgenic alopecia: 9% (2); sensory-motor polyneuropathy: 4.5% (1);Puffy hands: 4.5% (1); fever: 4.5% (1); lymphadenitis: 4.5% (1); cold sores: 4.5% (1), and retinal hemorrhage: 4.5% (1).OTHER ASSOCIATED ANTIBODIES:ANA: 91% (21/23)anti Ro60/SSA Ab: 30.5% (7)Anti Ro52 Ab: 30.5% (7)Anti RNP Ab: 22% (5)Anti-dsDNA: 17% (4)Anti-La/SSB Ab: 17% (4)Anticentromer Ab: 17% (4)Anti Mi-2 Ab: 13% (3)Other: anti Sm Ab: 9% (2); anticardiolipin Ab(IgG): 4.5% (1); PM/Scl: 4.5% (1); nucleosomes: 4.5% (1); Scl70: 4.5% (1); PL12: 4.5% (1); anti-U1-RNP: 4.5% (1) and NOR90: 4.5% (1).

Conclusion:

Anti-Ku Ab are related to a great variety of SAD, without being a specific marker of any of them, nor being associated with any specific clinical manifestation. We couldn’t confirm the existence of clinical phenotypes associated with the presence of these antibodies.

Disclosure of Interests:

L Montolio-Chiva: None declared, J. Narváez: None declared, Francisco Morandeira: None declared, Jordi Bas: None declared, Carla Marco: None declared, Xavier González: None declared, Juanjo J Alegre-Sancho Consultant of: UCB, Roche, Sanofi, Boehringer, Celltrion, Paid instructor for: GSK, Speakers bureau: MSD, GSK, Lilly, Sanofi, Roche, UCB, Actelion, Pfizer, Abbvie, Novartis, Eduardo Flores: None declared, I Vázquez-Gómez: None declared, Jose María López: None declared, Joan Miquel Nolla: None declared

AB0807 VITAMIN D ROLE IN VASCULAR DAMAGE PROGRESSION IN PATIENTS WITH PSORIATIC ARTHRITIS

Background:

Psoriatic arthritis (PsA) is associated with insufficent levels of vitamin D (25OHD) and an increased cardiovascular risk. Several studies, have shown an inverse relationship between 25OHD levels and cardiovascular damage.

Objectives:

To study the relationship between 25OHD and vascular damage, as well as its possible influence on its progression, in patients with PsA.

Methods:

Pre-post longitudinal study with analytical components. PsA patients with peripheral joint involvement were included. Demographic (sex, age), clinical [follow-up time, DAPSA, current treatment, body mass index (BMI), classic vascular risk factors, vascular events] and analytical variables [atherogenic index, glomerular filtration (GF-MDRD), glycosylated hemoglobin (HbA1c), CRP, ESR, 25OHD] were collected. We considered deficient level of 25OHD <20 ng/ml and insufficient <30 ng/ml. Basal vascular risk was estimated through SCORE tool. Extracranial carotid artery was explored with an Esaote MyLab70XVG ultrasound with linear probe (7-12mHz) and an automated program that measures intima media thickness (IMT) by radiofrequency, and the presence of atheroma plaques was evaluated following Mannheim consensus. Pulse wave velocity (PWV) was measured through Mobil o graph® dispositive. IMT≥900 µ and PWV≥ 10m/s were considered as pathological values. We repeat vascular study 3 years later. Vascular damage progression was defined as the appearance of atheroma plaques during the follow-up and/or an increase in their number. Statistical analysis was performed using SPSS 22.0 program.

Results:

78 patients were included. Eighteen patients were excluded due to high vascular risk [previous event, diabetes type II or type I with target organ injury and/or GF-MDRD< 60 ml/min]. 57.5% were women with a mean age of 54.2 (SD 10.9) years. The mean follow-up time was 96.8 (SD 163.6) months and mean DAPSA was 10.2 (SD 8.3). 96.2% of patients had received DMARDs and 42.3% biologicals, and 42.3% took calcium and 25OHD supplements. Mean BMI was 27.5 (SD 4.7) kg/m2. 42.3% had tobacco exposure, 29.5% were hypertensive and 32% dyslipidemic. Mean SCORE was 1.6 (SD 1.8) and mean 25OHD was 27.6 (DSD 11.6) ng/ml. 28.2% patients had 25OHD deficit and 60.3 % insufficiency. At the beginning, 32.1 % of patients had atheromatous plaques with a number of plaques around 1.7 (SD 1.2), and 6.7% and 19.7% had a pathological IMT or PWV, respectively. Baseline, we had not observed any association between 25OHD and the presence of atheroma plaques, IMT or PWV. Three years later, we detected progression of vascular damage in 31.2% patients. In these patients, the existence of hypovitaminosis D was associate with the appearance of atheroma plaques (p=0.043). This association desappeared in the multivariate analysis, in which only the CRP influenced the appearance of atherome plaques (OR: 1.4, IC 95% 1.04-1.98, p=0.025).

Conclusion:

Low 25OHD levels are not related to vascular damage or influence a posible progression of it in our serie. As might be expected, the progression of vascular damage depends on the inflammatory load in these patients.

Disclosure of Interests:

L Montolio-Chiva: None declared, M Robustillo-Villarino: None declared, Ana V Orenes Vera: None declared, Marta Aguilar-Zamora: None declared, C Vergara-Dangond: None declared, I Vázquez-Gómez: None declared, Eduardo Flores: None declared, A Sendra-García: None declared, À Martínez-Ferrer: None declared, Elia Valls-Pascual Grant/research support from: Roche, Novartis, and AbbVie, Speakers bureau: AbbVie, Lilly, Pfizer, MSD, Novartis, Janssen, Bristol Myers Squibb, UCB Pharma, D Ybáñez-García Speakers bureau: Lilly, Roche, Sanofi, V Núñez-Monje: None declared, I Torner-Hernández: None declared, Juanjo J Alegre-Sancho Consultant of: UCB, Roche, Sanofi, Boehringer, Celltrion, Paid instructor for: GSK, Speakers bureau: MSD, GSK, Lilly, Sanofi, Roche, UCB, Actelion, Pfizer, Abbvie, Novartis

AB0620 EFFECTIVENESS OF RITUXIMAB IN PATIENTS WITH EARLY DIFFUSE CUTANEOUS SYSTEMIC SCLEROSIS. A MULTICENTER ANALYSIS

Background:

Rituximab (RTX) is effective in improving skin affection in patients with diffuse cutaneous systemic sclerosis (DcSSc). However, there are few data on early use of this drug.

Objectives:

To evaluate RTX effectiveness for skin disease in patients with DcSSc of less than 3 years of evolution.

Methods:

Multicenter, observational and retrospective study. Patients with DcSSc starting RTX within 3 years since first non-Raynaud symptom were recruited. Demographic variables, time of disease duration at the beginning of RTX, immune pattern and time on RTX treatment were collected. Effectiveness was defined as modified Rodnan skin score (mRSS) improvement. Evaluations were done by the same experienced rheumatologist. Patients subjective perception of skin hardening and/or tightness was evaluated. mRSS changes from baseline to 6 and 12 months after RTX beginning and, later on, to the last available observation were analysed using Wilcoxon test. Statistical analysis was performed with SPSS 20.0.

Results:

11 patients (8 women) were recruited from 2 university hospitals. Median age was 48 years (IQR 22). Median time since diagnosis to RTX beginning was 12 months (IQR 8). 5, 3 and 2 patients presented ATA +, RNPIII + and Ro-52 +, respectively. Median duration of RTX treatment was 12 months (IQR 68). Median baseline mRSS was 15.5 (IQR 18). Median mRSS after 6 and 12 months of RTX treatment and at last available mRSS evaluation was 15 (IQR 13), 14.5 (IQR 13) and 11 (IQR 16), respectively. mRSS showed statistically significant improvement at 6 (29%, IQR 37) and 12 months of RTX treatment (35%, IQR 34) and, thereafter, at last available observation (39%, IQR 51), compared to basal mRSS. Most patients reported subjective improvement at 6 (9 of 10 patients) and 12 months (6 of 7), and at last available evaluation (6 of 8); all other patients reported stability.

Conclusion:

In our experience, patients with DcSSc seem to benefit of early RTX treatment. Improvement may be seen as early as 6 months and seems to reach a plateau at 12 months.

Disclosure of Interests:

I Vázquez-Gómez: None declared, J. Narváez: None declared, J Lluch Pons: None declared, Marta Aguilar-Zamora: None declared, L Montolio-Chiva: None declared, Ana V Orenes Vera: None declared, Eduardo Flores: None declared, Elia Valls-Pascual Grant/research support from: Roche, Novartis, and AbbVie, Speakers bureau: AbbVie, Lilly, Pfizer, MSD, Novartis, Janssen, Bristol Myers Squibb, UCB Pharma, Desamparados Ybañez: None declared, À Martínez-Ferrer: None declared, A Sendra-García: None declared, Inmaculada Torner Hernández: None declared, V Núñez-Monje: None declared, Juanjo J Alegre-Sancho Consultant of: UCB, Roche, Sanofi, Boehringer, Celltrion, Paid instructor for: GSK, Speakers bureau: MSD, GSK, Lilly, Sanofi, Roche, UCB, Actelion, Pfizer, Abbvie, Novartis

AB0711 USEFULNESS OF THE TRABECULAR BONE SCORE AS A PREDICTOR OF VERTEBRAL FRACTURE IN PATIENTS WITH AXIAL SPONDYLOARTHROPATHY

Background:

In axial spondyloarthritis (axSpA) the risk of vertebral fracture is increased, not always corresponding with the values of bone mineral density (BMD). One possible explanation is that syndesmophytes interfere with these values. We consider whether the evaluation of trabecular microarchitecture by an accessible methodlike the Trabecular Bone Score (TBS), that does not involve additional irradiation neither seem to be influenced by the presence of syndesmophytes, may be an advantage to estimate the risk of fracture.

Objectives:

To estimate the prevalence of vertebral fractures in patients with axSpA. To assess the diagnostic accuracy of TBS and BMD for vertebral fracture, and if it is influenced by the presence of syndesmophytes. To analyze the correlation between the absolute values of BMD and TBS in the lumbar spine.

Methods:

Cross-sectional study. Patients were consecutive recruited. We collected demographic (sex, age), clinical (syndesmophytes, vertebral fracture, BASDAI, BASFI, time of evolution of axSpA, treatment) and analytical variables [vitamin D (1,25-OHD), CRP and ESR]. The BMD was determined using the Lunar Prodigy ProTM densitometer from GE Healthcare, to which the TBS iNsight® software version 2.2 was added to perform the TBS analysis. The presence of fracture was evaluated by radiology. The statistical analysis was performed with the SPSS 22.0 and OpenEpi softwares.

Results:

84 patients were included, 60 men and 24 women, with a mean age of 59 years (± SD 13). 51.2% had lumbar syndesmophytes. The prevalence of fractures was 13.7%, 95 CI (7.8-22.9). 51.2% were treated with NSAIDs, and 48.8% with biological drugs. The evolution of axSpA was > 10 years in 65.5%. The mean scores of BASDAI and BASFI were 3.7 and 4.3 respectively (± SD 2.2 and 2.3). The mean CRP value was 8.5 mg / L (± SD 8.4), ESR 12.2 mm / h (± SD 11.4) and 1.25-OHD 27.9 ng / dL (± SD 13.6).

According to the lumbar and femoral T Score, 9.5% and 15.5% of the patients were in the range of osteoporosis respectively.19% patients had a low TBS value (≤1.23).

Regarding the influence of syndesmophytes on TBS and BMD values, we found significant differences in lumbar spine BMD (p = 0.01) but not in total hip and femoral neck BMD (p = 0.2 and 0.3 respectively) nor in the TBS (p = 0.1).

Regarding the correlation of TBS and BMD values of the spine, no correlation was observed in patients with syndesmophytes, while a moderate correlation (r = 0.4, p = 0.02) was observed in patients without syndesmophytes.

In the univariate analysis, the factors related to the presence of vertebral fracture were age, female sex, absolute BMD values in the lumbar spine and total hip, and TBS values. No relationship was found with the rest of the variables. In the multivariate analysis, only the TBS showed a significant association with the presence of fractures (p =0.02).

Regarding the predictive capacity of fractures, TBS showed a higher sensitivity than that of BMD (55.6% versus 18.2% and 30% of BMD in the spine and hip respectively), being the specificity comparable (85.3% versus 91.3% and 85.1% of BMD in column and hip respectively).

Conclusion:

the prevalence of fractures was 13.7% among the patients studied, 95 CI (7.8-22.9). The presence of syndesmophytes influenced the values of lumbar BMD but not the hip BMD or those of the TBS. We found a correlation between the values of BMD of the spine and TBS only in patients who did not have syndesmophytes. Only TBS values were significantly related to the presence of fractures in the multivariate analysis. TBS showed greater sensitivity with similar specificity than BMD for the detection of vertebral fractures.

Disclosure of Interests:

Ana V Orenes Vera: None declared, L Montolio-Chiva: None declared, I Vázquez-Gómez: None declared, Eduardo Flores: None declared, Elia Valls-Pascual Grant/research support from: Roche, Novartis, and AbbVie, Speakers bureau: AbbVie, Lilly, Pfizer, MSD, Novartis, Janssen, Bristol Myers Squibb, UCB Pharma, À Martínez-Ferrer: None declared, Desamparados Ybañez: None declared, Luis García-Ferrer: None declared, María Vega-Martínez: None declared, Magdalena Graells-Ferrer: None declared, A Sendra-García: None declared, V Núñez-Monje: None declared, Inmaculada Torner Hernández: None declared, Juanjo J Alegre-Sancho Consultant of: UCB, Roche, Sanofi, Boehringer, Celltrion, Paid instructor for: GSK, Speakers bureau: MSD, GSK, Lilly, Sanofi, Roche, UCB, Actelion, Pfizer, Abbvie, Novartis

AB0806 DOES VITAMIN D INFLUENCE THE ACTIVITY OF THE DISEASE IN PATIENTS WITH PSORIATIC ARTHRITIS?

Background:

Several studies have shown an inverse relationship between vitamin D levels (25OHD) and disease activity in patients with rheumatoid arthritis (RA). However, the existing data in patients with psoriatic arthritis (PsA) are poor, and they use the DAS28 index as a peripheral joint activity marker by extrapolation with RA.

Objectives:

To analyze the relationship between 25OHD levels, disease activity and functional capacity in patients with PsA.

Methods:

Transversal, observational, descriptive study. We included PsA patients with peripheral joint involvement. We collected demographic variables (gender, age), clinical variables [follow-up, received treatments, TJC (68), SJC (68), VAS] and analytical variables (25OHD, CRP, ESR). We usedDisease activity in psoriatic arthritis(DAPSA) score to measure disease activity, and theHealth assessment questionnaire(HAQ) to determine functional capacity. Levels of 25 OHD <20 ng/ml and between 20-30 ng/ml were considered deficient and insufficient, respectively. Statistical analysis was made with SPSS 22.0. The descriptive analysis results were expressed as percentage and mean ± SD. We used Pearson’s correlation to assess the association between quantitative variables and T test to compare means between dichotomous variables.

Results:

125 patients were included, the majority women (60.8%), with an average age of 55.4 (SD 12.2) years. The average follow-up was 75.5 (SD 68.3) months. 97.6% of patients had received DMARDs and 40.8% biologics, and almost half of the patients (42.7%) took calcium and 25OHD supplements. The average value of 25OHD was 27.1 (SD 12.1) ng/ml, with 30% of patients having 25OHD deficit and 63.3% insufficiency. The majority of patients had an acceptable disease control, with a mean DAPSA of 10.5 (SD 7,9); and mean of CRP, ESR, TJC and SJC was 6.1 (SD 3.7) mg/l, 10.2 (SD 9.9) mm/h, 1.3 (SD 2.5) and 0.7 (SD 2.1), respectively. The average value of HAQ was 0.6 (SD 0.7). We observed an inverse correlation between 25OHD levels and joint counts, TJC (p=0.02) and SJC (p=0.03). On the other hand, patients with hypovitaminosis D presented a tendency to get higher scores in DAPSA index (P=0.07). We do not observe any relationship between 25OHD and HAQ.

Conclusion:

As can be seen in our sample, low values of 25OHD are related to increased disease activity in patients with PsA.

Disclosure of Interests:

L Montolio-Chiva: None declared, Ana V Orenes Vera: None declared, Marta Aguilar-Zamora: None declared, C Vergara-Dangond: None declared, I Vázquez-Gómez: None declared, Eduardo Flores: None declared, A Sendra-García: None declared, À Martínez-Ferrer: None declared, Elia Valls-Pascual Grant/research support from: Roche, Novartis, and AbbVie, Speakers bureau: AbbVie, Lilly, Pfizer, MSD, Novartis, Janssen, Bristol Myers Squibb, UCB Pharma, D Ybáñez-García Speakers bureau: Lilly, Roche, Sanofi, V Núñez-Monje: None declared, I Torner-Hernández: None declared, Juanjo J Alegre-Sancho Consultant of: UCB, Roche, Sanofi, Boehringer, Celltrion, Paid instructor for: GSK, Speakers bureau: MSD, GSK, Lilly, Sanofi, Roche, UCB, Actelion, Pfizer, Abbvie, Novartis

FRI0446 VIRAL ARTHRITIS: DESCRIPTIVE ANALYSIS OF A SERIES OF 131 PATIENTS

Background:

Arthritis of viral aetiology is considered the most frequent cause of acute arthritis. The most common etiologic agent is parvovirus B19 (B19). Besides, other viruses can lead to inflammatory joint disease, such as Epstein-Barr virus (EBV), Cytomegalovirus (CMV), Human immunodeficiency virus (HIV), Rubella, Mumps, Hepatitis B and C virus (HBV and HCV) and Chikungunya (in transcontinental travellers or immigrants).

Objectives:

To describe the epidemiological characteristics, clinical and analytical course, evolution and treatment of a series of patients with a confirmed diagnosis of viral arthritis.

Methods:

A descriptive study was performed, considering a series of cases of viral arthritis collected between 2000 and 2019. Epidemiological (sex, age, the season of the year, year of diagnosis, children of pediatric age), clinics (joint pattern, prodromes, accompanying clinic) and analytical (CRP, ESR, ANA, RF) variables were collected. Statistical analysis was performed with the SPSS 22.0 program.

Results:

The data of 131 patients (109 women, 22 men), with a mean age of 39.7 years (SD 11.9) were collected. 93.9% of the cases were produced by B19, 3.8% by EBV, and only 3 by other viruses (1 by CMV, 1 by HBV, 1 by Mumps). The highest incidence years were 2005(55 cases), 2000(10 cases) and 2016(8 cases). Almost half of the cases (46.6%) occurred in spring, while 32.8% in summer, 15.3% in winter and 5.3% in autumn. Contrary to the expectations, only 20% of the patients had children in pediatric age.

The most frequent clinical picture was acute polyarthritis (53.4%), followed by inflammatory polyarthralgias (19.1%). Moreover, acute oligoarthritis was present in 10.7% of cases, and acute monoarthritis in 3.1% of cases. More than half of the patients (54.2%) had prodromes, most frequently respiratory symptoms, and the joint clinic was accompanied by a skin rash in 35.1% and fever in 29% of cases. Analytically, 33.6% presented high CRP, 39.7% high ESR, 19.8% transient anemia, 9.9% positive ANA (4.6% transiently), 9.1% anti dc-DNA (7.6% transiently), and 10.7% positive RF (3.1% transiently). In 79.4% of cases, the clinic picture was limited, with a mean duration of 36 days (SD 47.7), but 12.3% had recurrences. The 69.5% of the patients needed treatment with acetaminophen and/or NSAIDs (6.7% did not need treatment), but corticotherapy was needed in 21.4% of cases. 4.6% of the cases evolved to chronicity, which made DMARD necessary in 3 patients (two of them with a final diagnosis of rheumatoid arthritis, being treated with Methotrexate and Leflunomide, and the third one had a diagnosis of undifferentiated connective disease, treated with Hydroxychloroquine).

Conclusion:

B19 remains the most common cause of viral arthritis in our population. It appears with a sporadic, occasionally epidemic, pattern of presentation, predominantly in warm seasons. A clinical presentation as an oligoarthritis or an acute monoarthritis or even the positivity of autoimmunity markers, should not make us rule out this possible aetiology. One out of 20 cases can evolve to chronicity and even make necessary the addition of DMARD.

Disclosure of Interests:

Ana V Orenes Vera: None declared, I Vázquez-Gómez: None declared, L Montolio-Chiva: None declared, Eduardo Flores: None declared, Desamparados Ybañez: None declared, Elia Valls-Pascual Grant/research support from: Roche, Novartis, and AbbVie, Speakers bureau: AbbVie, Lilly, Pfizer, MSD, Novartis, Janssen, Bristol Myers Squibb, UCB Pharma, À Martínez-Ferrer: None declared, A Sendra-García: None declared, V Núñez-Monje: None declared, Inmaculada Torner Hernández: None declared, Juanjo J Alegre-Sancho Consultant of: UCB, Roche, Sanofi, Boehringer, Celltrion, Paid instructor for: GSK, Speakers bureau: MSD, GSK, Lilly, Sanofi, Roche, UCB, Actelion, Pfizer, Abbvie, Novartis, Nagore Fernandez-Llanio: None declared

FRI0377 BARIATRIC SURGERY: EFFECTS ON BONE METABOLISM

Background:

There are few data about variations in bone metabolism associated with weight loss in obese patients undergoing bariatric surgery.

Objectives:

To assess the influence on the bone metabolism of bariatric surgery in morbidly obese patients.

Methods:

Longitudinal pre-post study with analytical components. All morbidly obese patients undergoing bariatric surgery were, prior to this, referred to Rheumatology Department. In all cases, the baseline characteristics of the patients were collected and a complete bone metabolic analytical study and bone densitometry (BMD) were requested. This same study was repeated one year later, with a window period of ± 3 months. Statistical analysis was performed with the SPSS 20.0 software.

Results:

Of the 91 patients included in the study and who underwent baseline BMD and analytical tests prior to surgery, only follow-up data of 27 patients could be collected at the time of the present data analysis. Within this sample, the median age was 54 years (AIQ 11), with 6 men and 21 women (11 premenopausal, 10 postmenopausal). Prior to surgery, median body mass index (BMI) was 39.2 (AIQ4.43) and median vitamin D (25OHD) level was 22 (AIQ 16). High values of PTH were detected in two patients. Regarding baseline BMD, 78% had normal values and 22% had values in the range of osteopenia.

After surgery, all patients presented a significant weight loss, being the median loss in BMI per year 9.8 Kg/m2(AIQ 3.8) as absolute value, and 25% (AIQ 8.12) as a percentage value. This weight loss was accompanied by a significant BMD worsening that was evident in all locations: lumbar spine (median -6.97%, AIQ 6.3), total hip (median -6.4%, AIQ 7.7) and femoral neck (median -3.57 %, AIQ 8); so that an additional 22% of patients changed to osteopenia values. All this despite a significant increase in 25OHD levels in all cases (35.7%; AIQ 52.3). No clinical or morphometric fractures were collected. Despite the parallel evolutionary course, the loss of BMI only showed a tendency to correlate with the decrease in bone mass in the femoral neck (p-value 0.089), but not in the other locations.

Conclusion:

In our sample of morbidly obese patients undergoing bariatric surgery, there is a significant and widespread loss of bone mineral density one year after the procedure, all this despite the supplementation and the increase in 25OHD levels. This loss only seems to be directly related to the decrease in weight at the femoral neck, just probably by a mechanism to reduce mechanical load.

Disclosure of Interests:

I Vázquez-Gómez: None declared, Ramón Trullenque Juan: None declared, Carlos Morillas Ariño: None declared, L Montolio-Chiva: None declared, Ana V Orenes Vera: None declared, Eduardo Flores: None declared, Elia Valls-Pascual Grant/research support from: Roche, Novartis, and AbbVie, Speakers bureau: AbbVie, Lilly, Pfizer, MSD, Novartis, Janssen, Bristol Myers Squibb, UCB Pharma, Desamparados Ybañez: None declared, À Martínez-Ferrer: None declared, Inmaculada Torner Hernández: None declared, V Núñez-Monje: None declared, A Sendra-García: None declared, Juanjo J Alegre-Sancho Consultant of: UCB, Roche, Sanofi, Boehringer, Celltrion, Paid instructor for: GSK, Speakers bureau: MSD, GSK, Lilly, Sanofi, Roche, UCB, Actelion, Pfizer, Abbvie, Novartis

Inducible knockout of ∆Np63 alters cell polarity and metabolism during pubertal mammary gland development

The ∆Np63 isoform of the p53-family transcription factor Trp63 is a key regulator of mammary epithelial stem cells that is involved in breast cancer development. To investigate the role of ∆Np63 at different stages of normal mammary gland development, we generated a ∆Np63-inducible conditional knockout (cKO) mouse model. We demonstrate that the deletion of ∆Np63 at puberty results in depletion of mammary stem cell-enriched basal cells, reduces expression of E-cadherin and β-catenin, and leads to a closed ductal lumen. RNA-sequencing analysis reveals reduced expression of oxidative phosphorylation (OXPHOS)-associated proteins and desmosomal polarity proteins. Functional assays show reduced numbers of mitochondria in the mammary epithelial cells of ΔNp63 cKO compared to wild-type, supporting the reduced OXPHOS phenotype. These findings identify a novel role for ∆Np63 in cellular metabolism and mammary epithelial cell polarity.

Peri-operative delineation of non-melanoma skin cancer margins in vivo with handheld reflectance confocal microscopy and video-mosaicking

BACKGROUND

The surgical removal of non-melanoma skin cancers (NMSCs) is guided by the pathologic examination of margins. However, the preparation of histopathology is time consuming, labour-intensive and requires separate laboratory infrastructure. Furthermore, when histopathology indicates positive margins, patients must return for re-excisions. Reflectance confocal microscopy (RCM) with a new video-mosaicking approach can noninvasively delineate margins directly on patients and potentially guide surgery in real-time, augmenting the traditional approaches of histopathology.

OBJECTIVE

To assess a new peri-operative RCM video-mosaicking approach for comprehensive delineation of NMSC margins on patients in vivo.

METHODS

Thirty-five patients undergoing Mohs micrographic surgery (MMS) in the Mohs surgery unit at Memorial Sloan Kettering Cancer Center, New York, NY were included in the study. RCM imaging was performed before and after the first staged excision by acquiring videos along the surgical margins (epidermal, peripheral and deep dermal) of each wound, which were subsequently processed into video-mosaics. Two RCM evaluators read and assessed video-mosaics, and subsequently compared to the corresponding Mohs frozen histopathology.

RESULTS

Reflectance confocal microscopy videos and video-mosaics displayed acceptable imaging quality (resolution and contrast), pre-operatively in 32/35 (91%) NMSC lesions and intra-operatively in 29/35 lesions (83%). Pre-operative delineation of margins correlated with the histopathology in 32/35 (91%) lesions. Intra-operative delineation correlated in 10/14 (71%) lesions for the presence of residual tumour and in 18/21 (86%) lesions for absence. Sensitivity/specificity were 71%/86% and 86%/81% for two RCM video-mosaic evaluators, and overall agreement was 80% and 83% with histopathology, with moderate inter-evaluator agreement (k = 0.59, P ≤ 0.0002).

CONCLUSIONS

Peri-operative RCM video-mosaicking of NMSC margins directly on patients may potentially guide surgery in real-time, serve as an adjunct to histopathology, reduce time spent in clinic and reduce the need for re-excisions. Further testing in larger studies is needed.

Vitamin B12 deficiency and clinical laboratory: Lessons revisited and clarified in seven questions

The objective of this review article is to address the most frequently asked questions that pathologists and primary care physicians might face when dealing with a patient with suspicion of vitamin B12 deficiency. More specifically, the article mainly discusses the importance and prevalence of the deficit, how to recognize it, and the important role of a prompt diagnosis confirmation based on laboratory biomarkers for efficient replacement therapy.

Survival, disease progression and prognostic factors in elderly patients with mycosis fungoides and Sézary syndrome: a retrospective analysis of 174 patients

BACKGROUND

Advanced age at diagnosis is considered a poor prognostic factor in mycosis fungoides (MF) and Sézary syndrome (SS).

OBJECTIVE

To evaluate the outcomes and prognostic factors in patients diagnosed at an advanced age (≥65 years) with MF/SS.

METHODS

Survival, progression rates and various clinical and histopathological variables were studied in a group of 174 elderly patients diagnosed with MF/SS between 1992 and 2015 at a single referral cancer center in the United States. Kaplan-Meier estimates were used to determine survival and progression and Cox proportional hazards regression univariate and multivariate models were used to identify prognostic factors.

RESULTS

Of 174 elderly patients, 76.4% were diagnosed with early-stage (clinical stages IA-IIA) and 23.6% with late-stage MF/SS (IIB-IV). Advanced age was associated with poor overall survival, but not with disease-specific survival (DSS) or progression-free survival (PFS). Gender, increasing clinical stage, T and B classifications, elevated lactate dehydrogenase (LDH) levels and development of large cell transformation (LCT) were significant predictors of poor survival or disease progression. Patients with early-stage MF and <10% total skin involvement (T1 classification) or patch-only disease (T1a/T2a) showed better PFS with no observed disease-specific mortality. Folliculotropic MF was associated with poor DSS in patients with early-stage disease.

CONCLUSIONS

Older age at diagnosis of MF/SS does not predict worse disease-specific outcomes. Elderly patients with early-stage disease, specifically involving less than 10% of the skin surface with patches but without plaques or folliculotropism, have an excellent prognosis. However, the development of LCT is a strong prognostic indicator of poor survival in elderly patients with MF/SS.

The Rbm38-p63 feedback loop is critical for tumor suppression and longevity

The RNA-binding protein Rbm38 is a target of p63 tumor suppressor and can in-turn repress p63 expression via mRNA stability. Thus, Rbm38 and p63 form a negative feedback loop. To investigate the biological significance of the Rbm38-p63 loop in vivo, a cohort of WT, Rbm38^-/-, TAp63^+/-, and Rbm38^-/-;TAp63^+/- mice were generated and monitored throughout their lifespan. While mice deficient in Rbm38 or TAp63 alone died mostly from spontaneous tumors, compound Rbm38^-/-;TAp63^+/- mice had an extended lifespan along with reduced tumor incidence. We also found that loss-of-Rbm38 markedly decreased the percentage of liver steatosis in TAp63^+/- mice. Moreover, we found that Rbm38 deficiency extends the lifespan of tumor-free TAp63^+/- mice along with reduced expression of senescence-associated biomarkers. Consistent with this, Rbm38^-/-;TAp63^+/- MEFs were resistant, whereas Rbm38^-/- or TAp63^+/- MEFs were prone, to cellular senescence. Importantly, we showed that the levels of inflammatory cytokines (IL17D and Tnfsf15) were significantly reduced by Rbm38 deficiency in senescence-resistant Rbm38^-/-;TAp63^+/- mouse livers and MEFs. Together, our data suggest that Rbm38 and p63 function as intergenic suppressors in aging and tumorigenesis and that the Rbm38-p63 loop may be explored for enhancing longevity and cancer management.

p53 and TAp63 participate in the recombination-dependent pachytene arrest in mouse spermatocytes

To protect germ cells from genomic instability, surveillance mechanisms ensure meiosis occurs properly. In mammals, spermatocytes that display recombination defects experience a so-called recombination-dependent arrest at the pachytene stage, which relies on the MRE11 complex—ATM—CHK2 pathway responding to unrepaired DNA double-strand breaks (DSBs). Here, we asked if p53 family members—targets of ATM and CHK2—participate in this arrest. We bred double-mutant mice combining a mutation of a member of the p53 family (p53, TAp63, or p73) with a Trip13 mutation. Trip13 deficiency triggers a recombination-dependent response that arrests spermatocytes in pachynema before they have incorporated the testis-specific histone variant H1t into their chromatin. We find that deficiency for either p53 or TAp63, but not p73, allowed spermatocytes to progress further into meiotic prophase despite the presence of numerous unrepaired DSBs. Even so, the double mutant spermatocytes apoptosed at late pachynema because of sex body deficiency; thus p53 and TAp63 are dispensable for arrest caused by sex body defects. These data affirm that recombination-dependent and sex body-deficient arrests occur via genetically separable mechanisms.

Meiosis is a specialized cell division that generates haploid gametes by halving chromosome content through two consecutive rounds of chromosome segregation. At the onset of the first meiotic division, SPO11 protein introduces double-strand breaks (DSBs) throughout the genome. These DSBs are repaired through homologous recombination, which promotes pairing and synapsis of the homologous chromosomes. Some DSBs will become repaired as crossovers, providing a physical connection between the homologous chromosomes which promotes correct chromosome segregation. In fact, recombination defects can lead to formation of aneuploid gametes, one of the major causes of miscarriages and chromosome abnormalities in humans. To protect germ cells from genomic instability and to produce balanced gametes, surveillance mechanisms ensure that meiosis occurs properly. It is known that in the presence of unrepaired DSBs a control mechanism promotes a spermatogenic block at the pachytene stage. Here we describe that, downstream MRE11-ATM-CHK2 pathway, p53 and TAp63 are the effectors responsible for activating recombination-dependent arrest in mouse spermatocytes.

Dielectrophoretic assembly of liquid-phase-exfoliated TiS3 nanoribbons for photodetecting applications

Liquid-phase exfoliation produces colloidal two-dimensional materials that can be assembled by dielectrophoresis to fabricate optoelectronic devices.

Acute kidney injury in critically burned patients resuscitated with a protocol that includes low doses of Hydroxyethyl Starch

Acute kidney injury (AKI) is an important complication in burn patients. Recently, it has been recommended that hydroxyethyl starch (HES) be avoided in burn patients because it increases the incidence of AKI. Our purpose was to study incidence of AKI in critically ill burn patients resuscitated with Ringer's solution and supplements of HES. We conducted an observational study of 165 patients admitted to the critical care burn unit (with 30 ± 15% TBSA burned). The main outcome measures were incidence of AKI, contributions of colloids and crystalloids, various severity scores, comorbidities, complications and mortality. According to the RIFLE criteria, 10 (6.1%) patients presented with Risk, 11 (6.7%) presented with Injury and 11 (6.7%) presented with Failure. According to the AKIN criteria, 9.7% presented stage I, 3% stage II and 10.3% stage III. Replacement therapy (RRT) was performed in 15 patients (9.1%), but in 6 of them RRT was employed in the final stages of multi-organ failure. The incidence of AKI in severe burn patients is high according to the RIFLE or AKIN criteria and these patients experience more complications and higher mortality. Our study suggests that the use of HES in low doses in the burn resuscitation phase does not cause more AKI than resuscitation without HES, but further evaluation is required. Further studies should be conducted.

Development of a biomimetic microfluidic oxygen transfer device

Blood oxygenators provide crucial life support for patients suffering from respiratory failure, but their use is severely limited by the complex nature of the blood circuit and by complications including bleeding and clotting. We have fabricated and tested a multilayer microfluidic blood oxygenation prototype designed to have a lower blood prime volume and improved blood circulation relative to current hollow fiber cartridge oxygenators. Here we address processes for scaling the device toward clinically relevant oxygen transfer rates while maintaining a low prime volume of blood in the device, which is required for clinical applications in cardiopulmonary support and ultimately for chronic use. Approaches for scaling the device toward clinically relevant gas transfer rates, both by expanding the active surface area of the network of blood microchannels in a planar layer and by increasing the number of microfluidic layers stacked together in a three-dimensional device are addressed. In addition to reducing prime volume and enhancing gas transfer efficiency, the geometric properties of the microchannel networks are designed to increase device safety by providing a biomimetic and physiologically realistic flow path for the blood. Safety and hemocompatibility are also influenced by blood-surface interactions within the device. In order to further enhance device safety and hemocompatibility, we have demonstrated successful coating of the blood flow pathways with human endothelial cells, in order to confer the ability of the endothelium to inhibit coagulation and thrombus formation. Blood testing results provide confirmation of fibrin clot formation in non-endothelialized devices, while negligible clot formation was documented in cell-coated devices. Gas transfer testing demonstrates that the endothelial lining does not reduce the transfer efficiency relative to acellular devices. This process of scaling the microfluidic architecture and utilizing autologous cells to line the channels and mitigate coagulation represents a promising avenue for therapy for patients suffering from a range of acute and chronic lung diseases.

On the van der Pauw's method applied to the measurement of low thermal conductivity materials

The electrical van der Pauw's method has recently been extended to measure the thermal conductivity of different elements and compounds. This technique provides an easy way to determine the sample in-plane thermal conductivity by avoiding the influence of the thermal contact resistances. However, the reported calculated error values appear to be underestimated when dealing with the materials with low thermal conductivity (<5 W/Km) at room temperature. The causes of this underestimation are investigated in this communication and it has been found that they are due to the drastic influence of conduction heat losses through the thermo-resistance wires as well as the resulting modification of the sample temperature map. Both phenomena lead to experimental values of the sample thermal conductivity, which are systematically higher than the tabulated ones. The magnitude of this systematic error is ∼100% dealing with the samples of macroscopic dimensions, and low thermal conductivity indicated that the obtained accurate measurements can be quite challenging.

Abstract 33: Unlocking Reprogramming Capability: Silencing Antiplasticity Gene p63 Enhances the Reprogramming of Fibroblasts into Induced Cardiomyocytes

Objective: In situ cellular reprogramming of cardiac fibroblasts into (induced) cardiomyocytes (iCMs) represents a promising new potential intervention for the treatment of heart failure. Despite encouraging in vivo data in rodent myocardial infarction models, the relative resistance of human cells to reprogramming may be a significant barrier to the clinical application of this new therapy. We hypothesized that knockdown of the anti-plasticity gene p63 could therefore be used to enhance cellular reprogramming efficiency.

Methods: p63 knockout (KO) murine embryonic fibroblasts (MEFs) and MEFs treated with p63 silencing shRNA were assessed for expression of the cardiomyocyte marker Cardiac Troponin T (cTnT) and pro-cardiogenic genes, with or without the treatment with known cardiac transcription factors Hand2 and Myocardin (HM).

Results: After 3 wks in culture, expression of the cardiomyocyte marker cTnT (FACS) was significantly greater in p63 KO MEFs than in wild-type (WT) MEFs or WT MEFs treated with transcription factors Hand2 and Myocardin (39% ± 8%, 2.0% ± 1% and 2.7 ± 0.3%, respectively, p < 0.05). Treatment of p63 KO MEFs with Hand2 and Myocardin further increased cTnT expression up to 74% ± 3%. Treatment of WT MEFs with p63 shRNA likewise yielded a 20-fold increase in cTnT expression (qPCR) without HM and a 600-fold increase with HM when compared to non-silencing shRNA treated MEFs. Consistent with these findings, p63 KO or p63 shRNA-treated MEFs demonstrated increased expression (qPCR) of pro-cardiogenic genes Gata4, Mef2c and Tbx5 compared to naïve or non-silencing shRNA treated MEFs. After treatment with p63 shRNA, adult human epidermal cells also demonstrated increased expression of cTnT, myosin heavy chain and pro-cardiogenic genes when analyzed by qPCR.

Conclusions: Downregulation of the anti-plasticity gene p63 enhances cellular reprogramming efficiency and iCM generation, as reflected in the increased expression of the cardiomyocyte marker cTnT and pro-cardiogenic genes Gata4, Mef2c and Tbx5. Use of such cellular plasticity enhancing strategies may be a useful strategy to overcome barriers to cellular reprogramming in the clinical arena.

Abstract LB-321: TP63 isoforms regulate distinct and cooperative transcriptional signatures that drive cancer progression and predict clinical outcomes

TP63 is required to maintain stem cell pluripotency and suppresses the metastatic potential of cancer cells through multiple mechanisms. Even though roles for Tp63 in cancer have been described, the transcriptional roles of TP63 isoforms, namely TAp63 and ΔNp63, in tumor development and progression have been perplexing due to their variable expression in tissues, their complex interaction with each other and with TP53, and the lack of adequate antibodies to distinguish between their isoforms. Of concern is the use of total p63 as a diagnostic marker for many epithelial cancers in the clinic with disregard of the existence and functions of the various isoforms, which may lead to improper diagnosis. These notions necessitate a deeper understanding of how the distinct transcriptional programs controlled by TP63 isoforms affect cancer progression and patient outcomes. To shed light on the activities of the TP63 isoforms in cancer development and progression, we conducted a pan-cancer analysis of The Cancer Genome Atlas (TCGA) to identify the transcriptional networks regulated by TAp63 and ΔNp63 using transcriptomes derived from epidermal cells of TAp63-/- and ΔNp63-/- mice. We then derived 17 cancer developmental (tumor versus corresponding normal) and 27 cancer progression (high stage versus low stage) signatures. Our analysis revealed a consistent tumor suppressive pattern for TAp63. In contrast, we identified pleiotropic roles for ΔNp63 in tumor development and progression. Our findings revealed a cooperative role between TAp63 and ΔNp63 via their gene signatures that predict survival and correlates with progression of cancer patients in bladder cancer (BLCA), clear cell renal cell carcinoma (KIRC), papillary renal cell carcinoma (KIRP) and low grade glioma. Importantly, we found that ΔNp63 transcriptional activity integrates the remodeling of extracellular matrix remodeling to provide an ideal environment in these cancers to undergo epithelial to mesenchymal transition and gain pluripotent stem cell characteristics, thus supporting tumor progression, while TAp63 activity acts to regulate the cell cycle required in stem cell maintenance which may further allow tumors to progress. These signatures are not only predictive of survival across stages, but can even stratify patients within the same stage into different survival groups in the genitourinary tumors as well as in low grade gliomas. We then validated our findings in independent cohorts. Our data describe a global approach for understanding transcriptional activities of TP63 isoforms across a large number of cancer types, potentially enabling the identification of patient subsets most likely to benefit from therapies predicated on manipulating specific TP63 isoforms in order to inhibit the acquisition of pluripotency potential.

Citation Format: Hussein Abbas, Kimal Rajapakshe, Justin Wong, Ngoc Hoang Bao Bui, Preethi Gunaratne, Kenneth Tsai, Cristian Coarfa, Elsa Flores. TP63 isoforms regulate distinct and cooperative transcriptional signatures that drive cancer progression and predict clinical outcomes. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-321.

Chemical controls on uranyl citrate speciation and the self-assembly of nanoscale macrocycles and sandwich complexes in aqueous solutions

Uranyl citrate forms trimeric species at pH > 5.5, but exact structural characteristics of these important oligomers have not previously been reported. Crystallization and structural characterization of the trimers suggests the self-assembly of the 3 : 3 and 3 : 2 U : Cit complexes into larger sandwich and macrocyclic molecules. Raman spectroscopy and ESI-MS have been utilized to investigate the relative abundance of these species in solution under varying pH and citrate concentrations. Additional dynamic light scattering experiments indicate that self-assembly of the larger molecules does occur in aqueous solution.

Loss of ΔNp63 impairs thymic epithelial progenitor survival and differentiation (HEM7P.234)

The thymic stroma consists primarily of thymic epithelial cells (TECs) that originate from endodermal progenitors in the 3rd pharyngeal pouch (pp). A common epithelial progenitor in fetal thymus differentiates into networks of cortical (cTEC) and medullary (mTEC) cells, which provide distinct maturation signals that support T cell generation. The transcription factor p63 is expressed in cTECs and mTECs and global deletion results in a severely hypoplastic thymus. Alternative promoters generate two p63 isoforms, TAp63 containing a transactivation (TA) domain and ΔNp63, lacking a TA domain. The roles of TAp63 and ΔNp63 in thymus organogenesis have not been determined. We find that TAp63 is undetectable in fetal or steady state adult thymus and deletion of TAp63 in fetal TECs does not affect thymus size or TEC development. In contrast, ΔNp63, is highly expressed by E9.5 and persists in cTECs and mTECs in the postnatal thymus. Using Foxn1Cre to delete ΔNp63fl/fl in TEC progenitors of the 3rd pp results in a severely hypoplastic thymic phenotype by E14.5. Patterning of 3rd pp endoderm into thymus- and parathyroid-fated domains is not disrupted. Plet1+ progenitor TECs are found at a normal frequency at E12.5; however, Plet1- TECs lacking ΔNp63 undergo apoptosis at a higher frequency than wildtype. Furthermore, surviving ΔNp63 null TECs fail to differentiate beyond an early progenitor state. We conclude that ΔNp63 is necessary for survival and differentiation of developing TECs.

Somatostatin therapy protects porcine livers in small-for-size liver transplantation

Small-for-size (SFS) injury occurs in partial liver transplantation due to several factors, including excessive portal inflow and insufficient intragraft responses. We aim to determine the role somatostatin plays in reducing portal hyperperfusion and preventing the cascade of deleterious events produced in small grafts. A porcine model of 20% liver transplantation is performed. Perioperatively treated recipients receive somatostatin and untreated controls standard intravenous fluids. Recipients are followed for up to 5 days. In vitro studies are also performed to determine direct protective effects of somatostatin on hepatic stellate cells (HSC) and sinusoidal endothelial cells (SEC). At reperfusion, portal vein flow (PVF) per gram of tissue increased fourfold in untreated animals versus approximately threefold among treated recipients (p = 0.033). Postoperatively, markers of hepatocellular, SEC and HSC injury were improved among treated animals. Hepatic regeneration occurred in a slower but more orderly fashion among treated grafts; functional recovery was also significantly better. In vitro studies revealed that somatostatin directly reduces HSC activation, though no direct effect on SEC was found. In SFS transplantation, somatostatin reduces PVF and protects SEC in the critical postreperfusion period. Somatostatin also exerts a direct cytoprotective effect on HSC, independent of changes in PVF.

Measurement of J/ψ azimuthal anisotropy in Au+Au collisions at sqrt[s(NN)]=200 GeV

The measurement of J/ψ azimuthal anisotropy is presented as a function of transverse momentum for different centralities in Au+Au collisions at sqrt[s(NN)]=200 GeV. The measured J/ψ elliptic flow is consistent with zero within errors for transverse momentum between 2 and 10 GeV/c. Our measurement suggests that J/ψ particles with relatively large transverse momenta are not dominantly produced by coalescence from thermalized charm quarks, when comparing to model calculations.

First Report of Zebra Chip and 'Candidatus Liberibacter solanacearum' on Potatoes in Nicaragua

In September 2011, potato (Solanum tuberosum) tubers grown in Nicaragua outside of Estelí and Jinotega were observed with internal discoloration suggestive of zebra chip (ZC); and the plants showed foliar symptoms of chlorosis, leaf scorching, wilting, vascular discoloration, swollen nodes, twisted stems, and aerial tubers (3). Disease incidence ranged from 50 to 95% in eight fields ranging from 5 to 12 ha in the Estelí and Jinotega regions of Nicaragua. Leaf samples and psyllids were collected from two fields, and total DNA was purified from the leaves of 17 symptomatic and 10 asymptomatic plants. DNA was also extracted from 20 individual potato psyllids. Primers specific for 16S rDNA (OA2 and OI2c) and the surface antigen gene (OMB 1482f and 2086r) of Candidatus Liberibacter solanacearum (CLs) were used to confirm the presence of the pathogen in infected potatoes and insects (2). All symptomatic potato leaf samples tested positive for the presence of CLs using both primers, and no asymptomatic plants had positive results. Seven insects tested positive for the presence of CLs. 16S rDNA sequences obtained for all positive samples (1,071 bp) were identical and showed 99 to 100% identity to a number of rDNA sequences of CLs in GenBank (Accession Nos. HM246509 and FJ957897). 16S rDNA sequences from two CLs-infected plants, one from Estelí, Nicaragua (JX559779) and one from Jinotega, Nicaragua (JK559780), were deposited in GenBank. Identity of insects was done using a morphological key, and then verified as Bactericera cockerelli using a real-time PCR assay with melt temperature analysis of the cytochrome c oxidase 1 gene, as described by Chapman et al. (1). Sequencing of the amplified DNA yielded an approximately 63-bp read, with 100% homology to reference sequences of B. cockerelli (AY971886) and those obtained from psyllids collected in McAllen, TX, in 2010. B. cockerelli samples were collected from both locations. Similar to previous reports of ZC in new locations, foliar and tuber symptoms associated with ZC were observed in all eight fields in these two Nicaraguan potato-growing regions, specific PCR amplification with two primer pairs was completed, 16S rDNA sequence analyses showed 100% similarity to reference sequences of CLs, and the presence of potato psyllids which tested positive for the presence of CLs provide evidence that ZC is now present in Nicaragua. Potatoes rank in the top 20 commodities produced in Nicaragua, resulting in >$4.5M annual revenue. Because CLs has caused significant economic damage to potatoes in the United States, Mexico, Guatemala, and Honduras, this finding has significance for potato production in Central America. References: (1) R. I. Chapman et al. Southwest. Entomol. 37:475, 2012. (2) J. M. Crosslin. Southwest. Entomol. 36:125, 2011. (3) L. W. Liefting et al. Internat. J. Syst. Evol. Microbiol. 59:2274, 2009.

Abstract 1123: OncomiR-569 hit p53 pathway and deregulate proliferation of ovarian epithelial cells

Background

The 3q26.2 loci amplification is present in a large proportion of high grade serous epithelial ovarian cancer (HGSEOC) is less frequently curable disease in the clinic. The 3q26.2 loci, which is present in at least 35% of HGSEOC, is large and structurally complex suggesting that multiple coding genes of the amplicon contribute to tumor initiation and progression either alone or through cooperative activity. Our high resolution SNP array mapping of 3q26.2 amplicon identified a microRNA named miR-569 is highly amplified in addition to the coding genes in a large set of ovarian cancer samples. Potential role of miR-569 is not characterized previously in the context of ovarian cancer and our study provide mechanism underlying the oncogenic role of miR569 in ovarian cancer.

Results

We demonstrated a strong correlation between 3q26.2 amplification and overexpression of miR569 in patient's samples of ovarian cancer. Importantly overexpression and knockdown of miR569 in normal epithelial cells altered their growth, proliferation, and lumen filling in 3-dimensional culture models in Matrigel. Ectopic expression of miR569 in epithelial cancer cells promoted tumor growth and metastatic potential of tumor cells in mouse xenograft models. In silico and in vitro experiments showed that miR-569 directly target and inhibited the expression of p53 induced tumor suppressor gene TP53INP1. TP53INP1 is transcriptionally regulated by p53 or p73 proteins, however miR-569 is a key post-transcriptional regulator of TP53INP1 expression independent of p53 or p73 proteins. Immunohistochemical and protein array analysis confirmed that TP53INP1 protein levels were higher in normal tissues compared to cancer tissues of breast and ovary. Reduced expression of TP53INP1 mRNA and protein were associated with worsened outcomes and promoted distant metastasis in the clinic. In consistent with our in vitro results, in vivo targeting of miR-569 markedly reduced tumor growth and metastatic spreads.

Discussion

Our studies combined with previous literature are compatible with a model wherein amplification of 3q26.2 increases miR569 levels resulting in decreased TP53INP1 levels independently of p53 or p73 function. Such a decrease in TP53INP1 subsequently reduces p53 phosphorylation resulting in a positive feedback loop and collapse the p53-mediated cell cycle regulation. Based on our preclinical results of antimiR-569 on cell survival, tumor growth and drug sensitivity inhibiting miR-569 activity or increasing TP53INP1 may be a valid therapeutic target to treat ovarian cancer.

Citation Format: Pradeep Raghavan, Fan Zhang, Sunila Pradeep, Yiling Lu, Anne-Lise Borresen-Dale, Elsa Flores, Anil Sood, Gordon Mills. OncomiR-569 hit p53 pathway and deregulate proliferation of ovarian epithelial cells. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1123. doi:10.1158/1538-7445.AM2013-1123

Observation of an energy-dependent difference in elliptic flow between particles and antiparticles in relativistic heavy ion collisions

Elliptic flow (v(2)) values for identified particles at midrapidity in Au + Au collisions, measured by the STAR experiment in the beam energy scan at RHIC at sqrt[s(NN)] = 7.7-62.4 GeV, are presented. A beam-energy-dependent difference of the values of v(2) between particles and corresponding antiparticles was observed. The difference increases with decreasing beam energy and is larger for baryons compared to mesons. This implies that, at lower energies, particles and antiparticles are not consistent with the universal number-of-constituent-quark scaling of v(2) that was observed at sqrt[s(NN)] = 200 GeV.