Preliminary results on a proposed histopathological assessment of predictive factors for basal cell carcinoma recurrence after primary free margin excision

Background

Basal cell carcinoma (BCC) incidence is steadily increasing but therapeutic solutions remain limited and present a public health challenge.

Aims

To identify predictive factors of BCC recurrence after primary free margin excision, with automated methods, by evaluating cell proliferation, the Hedgehog pathway activation and primary cilia.

Materials and Methods

This case–control study included 32 patients (16 with recurrence occurring at least 6 months after complete resection, and 16 without recurrence) who underwent surgery for BCC. Formalin‐fixed paraffin‐embedded cutaneous resections were processed for immunohistochemistry or immunostaining with the following primary antibodies: mouse anti‐MCM6, rabbit anti‐ARL13B and rabbit anti‐GLI1.

Results

BCC recurrence after free margin excision was significantly linked to a higher proliferative index (p < 0.001) and a lower cilia count (p = 0.041) in the primary lesion. No significant differences were observed regarding cilia length (p = 0.39) or GLI1‐positive nuclei.

Discussion

The complex interplay between essential signaling pathways, cell proliferation and cilia requires further experimental investigations in the context of BCC recurrence.

Conclusion

A higher proliferative index evaluated with MCM6 antibody could be a useful prognosis marker of BCC risk of recurrence. The lower cilia count in the primary lesion unveiled novel perspectives to understand BCC recurrence molecular mechanisms.

Outcome and molecular landscape of patients with PIK3CA-mutated metastatic breast cancer

BACKGROUND

α-Selective phosphatidylinositol 3-kinase (PI3K) inhibitors improve outcome in patients with PIK3CA-mutated, hormone receptor-positive (HR+)/Her2- metastatic breast cancer (mBC). Nevertheless, it is still unclear how to integrate this new drug family in the treatment landscape.

PATIENTS AND METHODS

A total of 649 patients with mBC from the SAFIR02 trial (NCT02299999), with available mutational profiles were selected for outcome analysis. PIK3CA mutations were prospectively determined by next-generation sequencing on metastatic samples. The mutational landscape of PIK3CA-mutated mBC was assessed by whole-exome sequencing (n = 617). Finally, the prognostic value of PIK3CA mutations during chemotherapy was assessed in plasma samples (n = 44) by next-generation sequencing and digital PCR.

RESULTS

Some 28% (104/364) of HR+/Her2- tumors and 10% (27/255) of triple-negative breast cancer (TNBC) presented a PIK3CA mutation (P < 0.001). PIK3CA-mutated HR+/Her2- mBC was less sensitive to chemotherapy [adjusted odds ratio: 0.40; 95% confidence interval (0.22-0.71); P = 0.002], and presented a worse overall survival (OS) compared with PIK3CA wild-type [adjusted hazard ratio: 1.44; 95% confidence interval (1.02-2.03); P = 0.04]. PIK3CA-mutated HR+/Her2- mBC was enriched in MAP3K1 mutations (15% versus 5%, P = 0.0005). In metastatic TNBC (mTNBC), the median OS in patients with PIK3CA mutation was 24 versus 14 months for PIK3CA wild-type (P = 0.03). We further looked at the distribution of PIK3CA mutation in mTNBC according to HR expression on the primary tumor. Some 6% (9/138) of patients without HR expression on the primary and 36% (14/39) of patients with HR+ on the primary presented PIK3CA mutation (P < 0.001). The level of residual PIK3CA mutations in plasma after one to three cycles of chemotherapy was associated with a poor OS [continuous variable, hazard ratio: 1.03, 95% confidence interval (1.01-1.05), P = 0.007].

CONCLUSION

PIK3CA-mutated HR+/Her2- mBC patients present a poor outcome and resistance to chemotherapy. Patients with PIK3CA-mutated TNBC present a better OS. This could be explained by an enrichment of PIK3CA mutations in luminal BC which lost HR expression in the metastatic setting.

TRIAL REGISTRATION

SAFIR02 trial: NCT02299999.

Impact of maternal low-level cadmium exposure on glucose and lipid metabolism of the litter at different ages after weaning

Cadmium (Cd) is a metal which may participate in the development of type II diabetes even if Cd exposure levels are mild. However, experimental studies focusing on daily environmentally relevant doses are scarce, particularly for glucose metabolism of the offspring of chronically exposed mothers. The aim is to measure the impact of maternal low level Cd exposure on glucose and lipid metabolism of offspring. Female rats were exposed to 0, 50 or 500 μg.kg^-1.d^-1 of CdCl₂, 21 days before mating and during 21 days of gestation and 21 days of lactation. Pups exposure was organized in 3 groups (control, Cd1, Cd2) according to renal dams' Cd burden. Parameters of glucose and lipid metabolisms were measured for the pups on post-natal day 21, 26 and 60. Maternal Cd exposure led to significant amounts of Cd in the liver and kidney of pups. At weaning, insulin secretion upon glucose stimulation was unchanged, but the removal of circulating glucose was slower for pups born from the lowest impregnated dams (Cd1). Five days after, glucose tolerance of all groups was identical. Thus, this loss of insulin sensitivity was reversed, in part by increased adiponectin secretion for the Cd1 group. Furthermore, pups from dams accumulating the highest levels of Cd (Cd2) exhibited a compensatory increased insulin pancreatic secretion, together with increased circulating non-esterified fatty acids, indicating the establishment of insulin resistance, 2 months after birth. This study has demonstrated the influence of maternal exposure to low levels of Cd on glucose homeostasis in the offspring that might increase the risk of developing type II diabetes later in life.

Abstract GS1-08: Genomic characterisation of metastatic breast cancer

Rationale: while large efforts have been done to characterize early breast cancer, little is known about the genomic landscape of metastatic breast cancer. In the present study, we performed whole exome sequencing of 800 metastatic breast cancers, in order to identify new candidate targets and better stratify patients eligible for innovative therapies.

Patients and Methods: Patients were selected to present a metastatic breast cancer and to have received a biopsy in the context of precision medicine trials (SAFIR01, SAFIR02, PERMED, MOSCATO, SHIVA). Samples with &gt;30% cancer cells, and normal DNA, were sequenced using Hiseq and Novaseq. Drivers were identified using MutSigCV. Actionability of somatic genetic alterations was determined based on OncoKB. Decomposition of mutational signatures was performed using deconstructSigs. Prognostic value was assessed using a cox model. TCGA database was used as comparator to identify gene alterations enriched in metastatic samples.

Results: results presented in the current abstract are based on the first 629 patients analyzed.Sequencing was performed in 387 patients with HR+/Her2- breast cancer, 186 triple negative breast cancers, and 32 Her2-overexpressing breast cancers. only 9 patients received a pretreatment with a CDK4 inhibitor. 24 driver genes were significantly mutated. In patients with HR+/Her2- breast cancer, 11 genes were found more frequently mutated in the metastatic setting as compared to early stage breast cancer. This includes TP53 (29%), KMT2C (13%), NCOR1 (8%), NF1 (7%), RB1 (4%), C16orf3 (2%), FRG1 (6%), ESR1 (21%), RIC8A (4%), AKT1 (7%), PLSCR5 (2%). In addition, in the whole population, KRAS was found mutated in 3% of samples (G12A/C/R/V) while its frequency of mutation in early breast cancer is &lt;1%. No gene alteration was found enriched in metastatic Her2+++ and TNBC. Copy number alterations were compared between metastatic and early breast cancer. 18 amplicons were found more frequently in HR+/Her2- metastatic breast cancers as compared to eBC. Among the genes enriched in metastatic samples, mutations in RB1 or NF1 were associated with a poor outcome ( median OS 9 and 13 months respectively, p=0.0038 and 0.01 respectively). 73% of patients presenting HR+/Her2- mBC had an actionable alteration, as compared to 55% of patients presenting HR+/Her2- eBC (p&lt;0.01). Patients with HR+/Her2- mBC presented an enrichment of gene alterations in the MAPK/ERK pathway (37% vs 22%) and in the HRD pathway (22% vs 10%). When the analysis focuses on mTNBC; the proportion of patient presenting an actionable alteration was comparable to the eTNBC. 11 (6%) and 16 (9%) patients presented a somatic mutation or homozygous gene deletion on BRCA1 and PTEN respectively.

We further assessed the mutational signatures in order to better understand which mutational processes could drive cancer progression. Metastatic HR+/Her2- mBC presented an increase in APOBEC, S3 (HRD), S10 (POLE-associated signature), S17 signatures as compared to early HR+/Her2- BC.

Conclusion: the present study, based on 629 patients, identifies 11 driver gene alterations and four mutational processes enriched in HR+/Her2- metastatic breast cancers. Final results on 800 patients will be presented.

Citation Format: Andre F, Filleron T, Ng C, Bertucci F, Letourneau C, Jacquet A, Piscuoglio S, Jimenez M, Bachelot T. Genomic characterisation of metastatic breast cancer [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr GS1-08.

Impact of chronic and low cadmium exposure of rats: sex specific disruption of glucose metabolism

BACKGROUND

Several epidemiological and animal studies suggest a positive association between cadmium (Cd) exposure and incidence of type 2 diabetes, but the association remains controversial. Besides, the experimental data have mainly been obtained with relatively high levels of Cd, over various periods of time, and with artificial routes of administration.

OBJECTIVES

Do environmental exposures to Cd induce significant disruption of glucose metabolism?

METHODS

Adults Wistar rats were exposed for three months to 0, 5, 50 or 500 μg.kg^-1.d^-1 of CdCl₂ in drinking water. Relevant parameters of glucose homeostasis were measured.

RESULTS

Cd accumulated in plasma, kidney and liver of rats exposed to 50 and 500 μg.kg^-1.d^-1, without inducing signs of organ failure. In rats drinking 5 μg.kg^-1.d^-1 for 3 months, Cd exposure did not lead to any significant increase of Cd in these organs. At 50 and 500 μg.kg^-1.d^-1 of Cd, glucose and insulin tolerance were unchanged in both sexes. However, females exhibited a significant increase of both fasting and glucose-stimulated plasma insulin that was assigned to impaired hepatic insulin extraction as indicated by unaltered fasting C-peptide plasma levels.

CONCLUSIONS

Glucose homeostasis is sensitive to chronic Cd exposure in a gender-specific way. Moreover, this study proves that an environmental pollutant such as Cd can have, at low concentrations, an impact on the glucose homeostatic system and it highlights the importance of a closer scrutiny of the underlying environmental causes to understand the increased incidence of type 2 diabetes.

Mitochondrial Morphology and Function of the Pancreatic β-Cells INS-1 Model upon Chronic Exposure to Sub-Lethal Cadmium Doses

The impact of chronic cadmium exposure and slow accumulation on the occurrence and development of diabetes is controversial for human populations. Islets of Langerhans play a prominent role in the etiology of the disease, including by their ability to secrete insulin. Conversion of glucose increase into insulin secretion involves mitochondria. A rat model of pancreatic β-cells was exposed to largely sub-lethal levels of cadmium cations applied for the longest possible time. Cadmium entered cells at concentrations far below those inducing cell death and accumulated by factors reaching several hundred folds the basal level. The mitochondria reorganized in response to the challenge by favoring fission as measured by increased circularity at cadmium levels already ten-fold below the median lethal dose. However, the energy charge and respiratory flux devoted to adenosine triphosphate synthesis were only affected at the onset of cellular death. The present data indicate that mitochondria participate in the adaptation of β-cells to even a moderate cadmium burden without losing functionality, but their impairment in the long run may contribute to cellular dysfunction, when viability and β-cells mass are affected as observed in diabetes.

The Blomia tropicalis allergen Blo t 7 stimulates innate immune signalling pathways through TLR2

BACKGROUND

Although the house dust mite species Blomia tropicalis is a leading cause of allergic diseases in tropical and subtropical regions, the identification and characterization of the allergenic proteins remain incomplete.

OBJECTIVE

We aimed to characterize a recombinant form of Blo t 7 (rBlo t 7) in terms of IgE reactivity, lipid-binding activity and ability to stimulate innate immunity.

METHODS

The mature Blo t 7 cDNA was cloned by PCR methods for the expression of a secreted form of the allergen in P. pastoris. The IgE reactivity to purified rBlo t 7 as well as the potential cross-reactivity with Der p 7 was determined by ELISA. The lipid-binding capacity of rBlo t 7 was assayed using fluorescent lipid probes. The stimulation of TLR2 signalling pathway by rBlo t 7 was examined in cell activation and reporter assays.

RESULTS

The amplified mature Blo t 7 cDNA revealed the presence of a 60 base pair insertion compared with the reference sequence registered in the GenBank database. Multiple protein sequence alignments of group 7 mite allergens confirmed that this longer deduced amino acid sequence was the authentic Blo t 7 polypeptide chain. Analysis of IgE reactivity can classify rBlo t 7 as an intermediate B. tropicalis allergen which displayed weak cross-reactivity with Der p 7. Purified rBlo t 7 was shown to bind selectively the naturally fluorescent lipid probe cis-parinaric (cPNA) with a dissociation constant of 2 μmol/L. The group 7 Blomia allergen stimulated the TLR2-, NF-kB- and MAPK-dependent production of IL-8 and GM-CSF in respiratory epithelial cells.

CONCLUSIONS & CLINICAL RELEVANCE

Through its propensity to transport fatty acids/lipids and to stimulate TLR2 signalling pathways in airway epithelial cells, Blo t 7 can represent a key allergen for the initiation of the B. tropicalis-induced airway inflammation.

Abstract PD8-12: Mutational processes, genome evolution and outcome in metastatic breast cancers

Background: to determine the distribution and evolution of mutational processes in metastatic breast cancers (mBC), together with their clinical relevance Methods: Whole exome sequencing (Hi-Seq, Illumina) and determination of copy number alterations (CNA) (CGH array / SNP6.0) were performed in 240 and 692 metastatic breast cancers respectively. Mutational processes were defined according to Alexandrov (Nature, 2013). Homologous Recombination Deficiency (HRD) was determined by genome wide assessment of loss-of-heteroygosity (LOH) on SNP6.0 (n = 210). Finally, genomic instability was assessed by the % of genome altered assessed by CGH / SNP6.0 Results: Whole exome sequencing showed that HR+/Her2- metastatic breast cancer presented an increased contribution of APOBEC-related signatures, as compared to early breast cancer (TCGA) (58% of the mutations vs 31%, p &lt; 0.0001). Twelve percent of the HR+/Her2- mBC acquired an hypermutator genotype ( &gt; 200 non-synonymous mutations). This acquisition of an hypermutator genotype was confirmed in five paired primary-metastatic samples. An operational APOBEC-related signature 13 was associated with a poor outcome in a multivariate analysis (HR: 1.75, 95%CI: 1.1-2.7, p = 0.017). High LOH score (HRD) was observed in 30% of HR+/Her2- mBC as compared to 13% of early HR+/Her2- early BC (p &lt; 0.0001). The opposite was observed in TNBC (43% in mTNBC versus 58% in early TNBC ,p = 0.032). High LOH score was associated with a trend for poor outcome in HR+/Her2- mBC (multivariate 1.67, 95%CI: 0.949-2.951, p = 0.075).The % of genome altered was associated with a poor outcome in multivariate analyses both in the overall and HR+/Her2- mBC (HR / 10 increase:1.144, 95%CI:1.038-1.261, p = 0.007 and HR:1.18, 95%CI:1.037-1.344, p = 0.012 respectively). Copy number analyses identified 143 genes that are more frequently amplified as compared to early breast cancers (FDR &lt; 0.01) Conclusions: metastatic HR+/Her2- metastatic breast cancer present an increased in APOBEC-related mutational burden and in LOH score as compared to early breast cancers. APOBEC-related signature 13 and genome instability are associated with a poor outcome and could be used in the future to better stratify metastatic breast cancer patients.

Citation Format: Patsouris A, Filleron T, Jacquet A, Goncalves A, Bonnefoi H, Letourneau C, Bachelot T, Jimenez M, Andre F. Mutational processes, genome evolution and outcome in metastatic breast cancers [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr PD8-12.

Chronic Exposure to Low-Level Cadmium in Diabetes: Role of Oxidative Stress and Comparison with Polychlorinated Biphenyls

Among the most important physiological functions, maintenance of the oxidation reduction equilibrium in cells stands out as a major homeostatic event. Many environmental contaminants efficiently trap cellular reducing compounds, but the actual importance of this mode of toxicity is far from being precisely known. This statement applies to cases of slowly developing chronic diseases, such as neurodegenerations, diabetes, and many others. The involvement of oxidative challenge in diabetes is considered in connection with chronic dietary exposure to low-level concentrations of cadmium. Comparison is made with polychlorobiphenyl molecules (PCB): they are structurally unrelated to cadmium, they preferentially distribute into different organs than cadmium, and they follow different metabolic pathways. Yet, they have also pro-oxidative properties, and they are associated with diabetes. Since neither cadmium nor PCB is a direct oxidant, they both follow indirect pathways to shift the redox equilibrium. Thus, a difference must be made between the adaptable response of the organism, i.e. the anti-oxidant response, and the irreversible damage generated by oxidizing species, i.e. oxidative damage, when exposure occurs at low concentrations. The approximate border between high and low levels of exposure is estimated in this review from the available relevant data, and the strengths and weaknesses of experimental models are delineated. Eventually, chronic low level exposure to these contaminants sparks cellular responses setting ground for dysfunction and disease, such as diabetes: oxidative damage is an accompanying phenomenon and not necessarily an early mechanism of toxicity.

The minor house dust mite allergen Der p 13 is a fatty acid-binding protein and an activator of a TLR2-mediated innate immune response

BACKGROUND

The house dust mite (HDM) allergen Der p 13 could be a lipid-binding protein able to activate key innate signaling pathways in the initiation of the allergic response. We investigated the IgE reactivity of recombinant Der p 13 (rDer p 13), its lipid-binding activities, and its capacity to stimulate airway epithelium cells.

METHODS

Purified rDer p 13 was characterized by mass spectrometry, circular dichroism, fluorescence-based lipid-binding assays, and in silico structural prediction. IgE-binding activity and allergenic potential of Der p 13 were examined by ELISA, basophil degranulation assays, and in vitro airway epithelial cell activation assays.

RESULTS

Protein modeling and biophysical analysis indicated that Der p 13 adopts a β-barrel structure with a predominately apolar pocket representing a potential binding site for hydrophobic ligands. Fluorescent lipid-binding assays confirmed that the protein is highly selective for ligands and that it binds a fatty acid with a dissociation constant typical of lipid transporter proteins. The low IgE-binding frequency (7%, n = 224) in Thai HDM-allergic patients as well as the limited propensity to activate basophil degranulation classifies Der p 13 as a minor HDM allergen. Nevertheless, the protein with its presumptively associated lipid(s) triggered the production of IL-8 and GM-CSF in respiratory epithelial cells through a TLR2-, MyD88-, NF-kB-, and MAPK-dependent signaling pathway.

CONCLUSIONS

Although a minor allergen, Der p 13 may, through its lipid-binding capacity, play a role in the initiation of the HDM-allergic response through TLR2 activation.

Patterns of IgE sensitization in house dust mite-allergic patients: implications for allergen immunotherapy

BACKGROUND

Understanding patterns of IgE sensitization in Dermatophagoides-allergic patients living in various geographical areas is necessary to design a product suitable for worldwide allergen immunotherapy (AIT).

METHODS

Using a HIFI Allergy customized microarray assay, IgEs specific for 12 purified allergens from Dermatophagoides pteronyssinus or D. farinae were assessed in sera from 1302 house dust mite (HDM)-allergic patients living in various areas. Comprehensive mass spectrometric (MS) analyses were conducted to characterize HDM extracts, as well as purified bodies and feces.

RESULTS

Patterns of IgE reactivity to HDM allergens are comparable in all cohorts of patients analyzed, encompassing adults and 5- to 17-year-old children, as well as American, Canadian, European, and Japanese patients. Overall, >70% and >80% of HDM-allergic patients are sensitized to group 1 and group 2 allergens, respectively, from D. pteronyssinus and/or D. farinae species. Furthermore, 20-47% of patients also have IgEs to allergens from groups 4, 5, 7, 13, 15, 21, and 23. All patients have IgEs to allergens present in mite bodies and feces. MS-based analyses confirmed the presence of mite allergens recorded by IUIS in D. pteronyssinus and D. farinae extracts, with groups 2, 8, 10, 11, 14, and 20 prominent in bodies and groups 1, 6, 18, and 23 well represented in feces.

CONCLUSIONS

Mite-specific AIT should rely upon a mixture of D. pteronyssinus and D. farinae extracts, manufactured from both feces and bodies. Such a combination is appropriate to treat children and adult Dermatophagoides-allergic patients from Asia, Europe, and North America.

Development of recombinant stable house dust mite allergen Der p 3 molecules for component-resolved diagnosis and specific immunotherapy

BACKGROUND

The allergen Der p 3 is underrepresented in house dust mite (HDM) extracts probably due to autolysis. Recombinant stable molecule of the allergen is thus needed to improve the diagnosis of allergy and the safety and efficacy of immunotherapy.

OBJECTIVE

The current study reports the immunological characterization of two recombinant molecules of the HDM allergen Der p 3 as useful tools for diagnosis and immunotherapy.

METHODS

Recombinant mature (rDer p 3) and immature (proDer p 3) Der p 3 and their corresponding S196A mutants were produced in Pichia pastoris and purified. The stability, IgE-binding capacity and allergenicity of the different proteins were analysed and compared with those of the major mite allergen Der p 1 used as a reference. Additionally, the immunogenicity of the different allergens was evaluated in a murine model of Der p 3 sensitization.

RESULTS

Compared to the IgE reactivity to recombinant and natural Der p 3 (nDer p 3), the mean IgE binding of patient's sera to rDer p 3-S196A (50%) was higher. The poorly binding to nDer p 3 or rDer p 3 was due to autolysis of the allergen. Contrary to Der p 3, proDer p 3 displayed very weak IgE reactivity, as measured by sandwich ELISA and competitive inhibition, rat basophil leukaemia degranulation and human basophil activation assays. Moreover, proDer p 3 induced a TH 1-biased immune response that prevented allergic response in mice but retained Der p 3-specific T-cell reactivity.

CONCLUSION

rDer p 3-S196A should be used for the diagnosis of HDM allergy elicited by Der p 3, and proDer p 3 may represent a hypoallergen of Der p 3.

[Quilting suture after mastectomy in prevention of postoperative seroma: a prospective observational study]

OBJECTIVES

The occurrence of a postoperative seroma is the main complication of mastectomy. In 2011, Ouldamer et al. adapted a quilting technique used in reconstructive surgery in mastectomy closure. The aim of this study is to evaluate the impact of quilting in the prevention of postoperative seroma.

PATIENTS AND METHODS

This is an observational prospective study to the Centre Hospital-University of Tours. Hundred and forty-four patients who underwent a mastectomy between January 1st, 2011 and October 1st, 2012 were included. Patients were divided into 2 groups, one with a classic wound closure with drainage and the second with quilting suture of skin flaps to the underlying musculature after mastectomy without drainage.

RESULTS

Quilting suture significantly reduces the postoperative seroma appearance (OR=0.15; CI95% [0.06-0.39]; P<0.001). Operative time is increased by 20minutes in the quilted group (P<0.001). Postoperative pain is not changed by quilting. The duration of hospitalization is significantly shorter (5.09±1.46 days versus 6.49±2.77 days; P<0.001). Quality of the healing and appearance of the scar, rated by patients, are identical in both groups.

CONCLUSION

Quilting is an effective method not only for prevention of seroma, but also for reducing of hospitalization duration, without increasing of postoperative pain and complications.

Expression of sarco (endo) plasmic reticulum calcium ATPase (SERCA) system in normal mouse cardiovascular tissues, heart failure and atherosclerosis

The sarco(endo)plasmic reticulum Ca(2+)ATPases (SERCA) system, a key regulator of calcium cycling and signaling, is composed of several isoforms. We aimed to characterize the expression of SERCA isoforms in mouse cardiovascular tissues and their modulation in cardiovascular pathologies (heart failure and/or atherosclerosis). Five isoforms (SERCA2a, 2b, 3a, 3b and 3c) were detected in the mouse heart and thoracic aorta. Absolute mRNA quantification revealed SERCA2a as the dominant isoform in the heart (~99%). Both SERCA2 isoforms co-localized in cardiomyocytes (CM) longitudinal sarcoplasmic reticulum (SR), SERCA3b was located at the junctional SR. In the aorta, SERCA2a accounted for ~91% of total SERCA and SERCA2b for ~5%. Among SERCA3, SERCA3b was the most expressed (~3.3%), mainly found in vascular smooth muscle cells (VSMC), along with SERCA2a and 2b. In failing CM, SERCA2a was down-regulated by 2-fold and re-localized from longitudinal to junctional SR. A strong down-regulation of SERCA2a was also observed in atherosclerotic vessels containing mainly synthetic VSMCs. The proportion of both SERCA2b and SERCA3b increased to 9.5% and 8.3%, respectively.

IN CONCLUSION

1) SERCA2a is the major isoform in both cardiac and vascular myocytes; 2) the expression of SERCA2a mRNA is ~30 fold higher in the heart compared to vascular tissues; and 3) nearly half the amount of SERCA2a mRNA is measured in both failing cardiomyocytes and synthetic VSMCs compared to healthy tissues, with a relocation of SERCA2a in failing cardiomyocytes. Thus, SERCA2a is the principal regulator of excitation-contraction coupling in both CMs and contractile VSMCs.

Efficient strategies for TALEN-mediated genome editing in mammalian cell lines

TALEN is one of the most widely used tools in the field of genome editing. It enables gene integration and gene inactivation in a highly efficient and specific fashion. Although very attractive, the apparent simplicity and high success rate of TALEN could be misleading for novices in the field of gene editing. Depending on the application, specific TALEN designs, activity assessments and screening strategies need to be adopted. Here we report different methods to efficiently perform TALEN-mediated gene integration and inactivation in different mammalian cell systems including induced pluripotent stem cells and delineate experimental examples associated with these approaches.

[Interest of emergency endocervical specimens]

OBJECTIVE

To estimate the diagnosis profitability of endocervical specimen (ES) within the framework of a teaching gynecological emergency department by studying the circumstances of realization and its bacteriological results.

PATIENTS AND METHODS

We included in our study all the patients who had a gynecological exam with an ES during a consultation in our gynecological teaching emergency department of Tours between January 1st, 2012 and December 31st, 2012. We estimated the diagnosis profitability of realization of the ES (positivity rate within the population with ES, diagnosis correction in case of pelvic inflammatory disease).

RESULTS

Over the study period, 614 (12.4%) women consulting in our emergency department had an ES, which was positive among 102 (16.6%) of them, and a diagnosis of pelvic inflammatory disease in 64 patients. ES had a higher pertinence in case of abdominal pain and a lesser one in case of pregnancy for whom ES realisation must be limited. The diagnosis correction due to ES was observed in 46.8% of pelvic inflammatory disease.

CONCLUSION

The diagnostic profitability of the endocervical specimen in our emergency department was low, taking into account the whole cohort, but ES permitted to correct the diagnosis in about half of diagnosed pelvic inflammatory diseases. The endocervical specimens seem to have no profit in pregnant women.

Voluntary physical activity protects from susceptibility to skeletal muscle contraction-induced injury but worsens heart function in mdx mice

It is well known that inactivity/activity influences skeletal muscle physiological characteristics. However, the effects of inactivity/activity on muscle weakness and increased susceptibility to muscle contraction-induced injury have not been extensively studied in mdx mice, a murine model of Duchenne muscular dystrophy with dystrophin deficiency. In the present study, we demonstrate that inactivity (ie, leg immobilization) worsened the muscle weakness and the susceptibility to contraction-induced injury in mdx mice. Inactivity also mimicked these two dystrophic features in wild-type mice. In contrast, we demonstrate that these parameters can be improved by activity (ie, voluntary wheel running) in mdx mice. Biochemical analyses indicate that the changes induced by inactivity/activity were not related to fiber-type transition but were associated with altered expression of different genes involved in fiber growth (GDF8), structure (Actg1), and calcium homeostasis (Stim1 and Jph1). However, activity reduced left ventricular function (ie, ejection and shortening fractions) in mdx, but not C57, mice. Altogether, our study suggests that muscle weakness and susceptibility to contraction-induced injury in dystrophic muscle could be attributable, at least in part, to inactivity. It also suggests that activity exerts a beneficial effect on dystrophic skeletal muscle but not on the heart.

Myoblasts and embryonic stem cells differentially engraft in a mouse model of genetic dilated cardiomyopathy

The functional and architectural benefits of embryonic stem cells (ESC) and myoblasts (Mb) transplantations into infarcted myocardium have been investigated extensively. Whereas ESC repopulated fibrotic areas and contributed to myocardial regeneration, Mb exerted their effects through paracrine secretions and scar remodeling. This therapeutic perspective, however, has been less explored in the setting of nonischemic dilated cardiomyopathies (DCMs). Our aim was to compare the integration and functional efficacy of ESC committed to cardiac fate by bone morphogenic protein 2 (BMP-2) pretreatment and Mb used as gold standard following their transplantation into the myocardium of a mouse model of laminopathy exhibiting a progressive and lethal DCM. After 4 and 8 weeks of transplantation, stabilization was observed in Mb-transplanted mice (P = 0.008) but not in groups of ESC-transplanted or medium-injected animals, where the left ventricular fractional shortening (LVFS) decreased by 32 ± 8% and 41 ± 8% respectively. Engrafted differentiated cells were consistently detected in myocardia of mice receiving Mb, whereas few or no cells were detected in the hearts of mice receiving ESC, except in two cases where teratomas were formed. These data suggest that committed ESC fail to integrate in DCM where scar tissue is absent to provide the appropriate niche, whereas the functional benefits of Mb transplantation might extend to nonischemic cardiomyopathy.

miR-424/322 regulates vascular smooth muscle cell phenotype and neointimal formation in the rat

AIMS

Our aim was to identify new microRNAs (miRNAs) implicated in pathological vascular smooth muscle cells (VSMCs) proliferation and characterize their mechanism of action.

METHODS AND RESULTS

MicroRNAs microarray and qRT-PCR results lead us to focus on miR-424 or its rat ortholog miR-322 (miR-424/322). In vitro mir-424/322 level was decreased shortly after the induction of proliferation and increased in a time-dependent manner later on. In vivo its expression increased in the rat carotid artery from Day 4 up to Day 30 after injury. miR-424/322 overexpression in vitro inhibited proliferation and migration without affecting apoptosis and prevented VSMC dedifferentiation. Furthermore, miR-424/322 overexpression resulted in decreased expression of its predicted targets: cyclin D1 and Ca(2+)-regulating proteins calumenin and stromal-interacting molecule 1 (STIM1). Using reporter luciferase assays, we confirmed that cyclin D1 and calumenin mRNAs were direct targets of miR-322, whereas miR-322 effect on STIM1 was indirect. Nevertheless, consistent with the decreased STIM1 level, the store-operated Ca(2+) entry was reduced. We hypothesized that miR-424/322 could be a negative regulator of proliferation overridden in pathological situations. Thus, we overexpressed miR-424/322 in injured rat carotid arteries using an adenovirus, and demonstrated a protective effect against restenosis.

CONCLUSION

Our results demonstrate that miR-424/322 is up-regulated after vascular injury. This is likely an adaptive response to counteract proliferation, although this mechanism is overwhelmed in pathological situations such as injury-induced restenosis.

Evaluation of therapeutic sublingual vaccines in a murine model of chronic house dust mite allergic airway inflammation

BACKGROUND

Second generation therapeutic vaccines based upon recombinant allergens or natural extracts, potentially formulated in vector systems or adjuvants, are being developed. To this aim, preclinical studies in relevant animal models are needed to select proper allergens, formulations and administration schemes.

OBJECTIVE

To develop a chronic house dust mite (HDM) allergy model to evaluate sublingual therapeutic vaccine candidates.

METHODS

The BABL/c mice that were used were sensitized with Dermatophagoides pteronyssinus (Dpte) and Dermatophagoides farinae (Dfar) mite extracts by intraperitoneal injections followed by aerosol exposures. Animals subsequently underwent sublingual immunotherapy (SLIT) with either Dpte, Dfar or Dpte/Dfar extracts, twice a week for 8 weeks. SLIT efficacy was assessed by whole body plethysmography, lung histology and broncho-alveolar lavages cell counts. Specific T cell and antibody responses to major and minor HDM allergens were monitored in tissues and serum/saliva, respectively.

RESULTS

Mice sensitized to Dpte and Dfar allergens exhibited strong airway hyperresponsiveness (AHR) and lung inflammatory infiltrates including eosinophils. Sensitized animals mounted Th2-biased cellular and humoral responses specific for group 1 and 2 major allergens, as well as group 5, 7 and 10 minor allergens. This phenotype was sustained for at least 2 months, allowing the evaluation of immunotherapeutic protocols with HDM extracts-based vaccines. In this model, SLIT decreased AHR and Th2 responses and induced HDM-specific IgAs in saliva. The Dpte/Dfar mix proved the most efficacious when compared to Dpte or Dfar extracts alone.

CONCLUSIONS AND CLINICAL RELEVANCE

The efficacy of a sublingual vaccine based on a Dpte/Dfar allergen extract mix was demonstrated in a well standardized murine model of chronic allergic airway inflammation based on clinically relevant mite allergens. The latter will be used as a benchmark for evaluation of future vaccines, including recombinant allergens. This HDM allergic airway inflammation animal model is a useful tool to design and select candidate vaccines to be tested in humans.

Interactions of airway epithelium with protease allergens in the allergic response

Among the apparently innocuous environmental proteins routinely inhaled by human subjects, only a small proportion of these antigens triggers allergy in susceptible individuals. Although the molecular basis of the allergenicity of these airborne proteins remains to be fully characterized, numerous studies suggest that the ability of such proteins to promote allergic responses is at least due to their proteolytic activity. This review will summarize insights into the interactions of protease allergens with the respiratory epithelium. In addition to their capacity to facilitate their antigen presentation through epithelial barrier degradation, protease allergens can directly activate airway mucosal surfaces to recruit inflammatory cells and to initiate the airway remodelling process. A greater understanding of the effects of protease allergens in the airways inflammation as well as on the relevant targets could define novel therapeutic strategies for the treatment allergic asthma.

Production and immunogenicity of hypoallergenic codon-optimized DNA vaccine encoding mature Der p 1 allergen

BACKGROUND

Genetic vaccination with plasmid DNA encoding allergens is a promising potential approach for the treatment or prevention of allergy. Nonetheless, because the allergens expressed can display immunoglobulin (Ig) E reactivity, methods to deliver hypoallergenic variants can minimize the risk of type 2 helper (T(H)2) cell priming after DNA immunization.

METHODS

A humanized synthetic gene encoding mature Dermatophagoides pteronyssinus group 1 (Der p 1) allergen was cloned into the pHIS expression vector carrying unmethylated CpG 2006 (CpG 2006) motif but devoid of signal sequence. The immunogenicity of this DNA construct was compared in naïve mice with that of recombinant ProDer p 1 protein adjuvanted with alum.

RESULTS

Codon optimization of the cDNA encoding mature Der p 1 markedly improved allergen expression. Mature Der p 1, expressed intracellularly in Human Embryonic Kidney 293 cells (HEK 293 cells) transfected with codon-optimized Der p 1 cDNA (pHIS-mHuDer p 1), was shown to be hypoallergenic as it displayed no IgE reactivity. Intradermal vaccinations of naïve Balb/C mice with pHIS-mHuDer p 1 elicited an allergen-specific T(H)1 response characterized by the production of specific IgG2a, a very low amount of specific IgG1, and no specific IgE. Lipoplex formulation with cationic liposome composed of lecithin, N-[1-(2,3-Dioleoyloxy)propyl]-N,N,N-trimethylammonium methylsulfate (DOTAP) and cholesterol not only accelerated the induction of T(H)1 response but also increased its intensity.

CONCLUSION

A codon-optimized DNA vaccine encoding mature Der p 1 in a lipoplex formulation could represent a promising hypoallergenic vaccine candidate for safer immunotherapy against house dust mite allergy.

The challenge of preserving renal function after liver transplantation

Thanks to new surgical techniques and the use of calcineurin inhibitors for the prevention of allograft rejection, the long-term outcome of liver transplantation has recently improved. In case of liver transplantation, the occurrence of renal failure can impair the outcome. Renal function preservation is, therefore, necessary to improve transplantation outcome.

Immunomodulatory properties of Lactobacillus plantarum and its use as a recombinant vaccine against mite allergy

BACKGROUND

Selected lactic acid bacteria were reported to prevent atopic dermatitis and experimental asthma but the mechanisms of their immunomodulatory effects are not fully elucidated. In this study, the signaling pathways triggered by Lactobacillus plantarum NCIMB8826 were investigated and the potential use of this strain producing a variant of the mite allergen Der p 1 as live vaccine vehicle was evaluated.

METHODS

Mouse bone marrow-derived dendritic cells were stimulated with wild-type or a L. plantarum teichoic acid mutant to evaluate the secretion of cytokines. A recombinant L. plantarum expressing Der p 1 was engineered, its in vitro immunomodulatory properties were characterized and its prophylactic potential was evaluated in a Der p 1-sensitization murine model.

RESULTS

Mouse dendritic cells stimulated by L. plantarum triggered the release of interleukin-10 (IL-10), IL-12 p40, IL-12 p70 and tumor necrosis factor-alpha (TNF-alpha). IL-12 p40 secretion was dependent on nuclear factor-kappaB (NF-kappaB), mitogen-activated protein (MAP) kinases, Toll-like receptor 2 (TLR2), TLR9 and on the bacterial teichoic acid composition. Recombinant L. plantarum producing Der p 1 exhibited similar immunostimulatory properties as wild-type. Prophylactic intranasal pretreatment of mice with this recombinant strain prevented the development of the typical Th2-biased allergic response by a drastic reduction of specific IgE and the induction of protective allergen-specific IgG2a antibodies. Moreover, both wild-type or recombinant L. plantarum reduced airway eosinophilia following aerosolized allergen exposure and IL-5 secretion upon allergen restimulation.

CONCLUSION

By combining both Th1-type immunostimulatory properties and an efficient allergen delivery capacity, recombinant L. plantarum producing Der p 1 represents a promising vaccine against house dust mite allergy.

Prevention of calcineurin inhibitor nephrotoxicity in renal transplantation

Calcineurin inhibitors (CNI) cyclosporine (Csa) and tacrolimus (Tac) are now first intention immunosuppressive drugs in renal transplantation. However, although these treatments are effective for preventing allograft rejection, they are nephrotoxic: they can cause chronic renal dysfunction and degradation of renal graft function [Nankivell BJ, et al. The natural history of chronic allograft nephropathy. N Engl J Med. 2003 Dec 11;349(24):2326-33]. In view of these undesirable effects, several strategies have been developed to minimize or even avoid their use. These strategies are reviewed and discussed in this paper.

In vivo and in vitro immunomodulation of Der p 1 allergen-specific response by Lactobacillus plantarum bacteria

BACKGROUND

Lactic acid bacteria (LAB) were reported to reduce some allergic manifestations in mice and humans but their impact on the aeroallergen-dependent immune mechanisms is still debated.

OBJECTIVE

The potential capacities of Lactobacillus plantarum NCIMB8826 to reduce the allergic response induced by Der p 1, the major house dust mite allergen of Dermatophagoides pteronyssinus, were evaluated in vivo and in vitro. Methods First, the effect of the intranasal co-administration of LAB and purified Der p 1 allergen before a sensitization protocol was evaluated. The allergen-specific antibody and cellular responses as well as airway inflammation were measured. Second, the impact of LAB on the cytokine profile of spleens cells from Der p 1-sensitized mice was assessed. Third, upon stimulation with LAB, the levels of cytokine produced by dendritic cells derived from the bone marrow (BMDCs) of wild-type, Toll-like receptor 2 (TLR2)-, TLR4- and MyD88-KO mice were compared. Results The co-application of L. plantarum and Der p 1 induced a T-helper type 1 (Th1)-biased allergen-specific IgG response, the absence of specific IgE response and favoured the production of INF-gamma upon allergen re-stimulation. Moreover, the previous LAB administration reduced the development of bronchoalveolar lavage eosinophilia usually induced by aerosol exposure. Additionally, the studied LAB strain was shown to modify in vitro the cytokine level produced by Der p 1-sensitized spleen cells mainly towards a Th1 profile. Finally, L. plantarum stimulated high IL-12 and moderate IL-10 production in mouse BMDCs notably through the TLR2-, MyD88-dependent and TLR4-independent pathway.

CONCLUSION

In vivo co-administration of probiotic LAB with Der p 1 might prevent the development of the mite allergic response. The probiotic L. plantarum was shown to display in vitro therapeutic potentials for the treatment of allergy and to trigger the immune system by a TLR2- and MyD88-dependent signalling pathway.

[Sexual assault: medicolegal findings and legal outcomes (analysis of 756 cases)]

OBJECTIVES

We describe the medico-legal findings in a population of sexual assault cases assessed in an urban referral center, analyse the legal outcomes in each case and determine whether the medico-legal findings were associated with conviction of the assailant.

MATERIALS AND METHODS

We performed a retrospective study of medico-legal reports in all the sexual assault cases reported in Tours during a 7-year period. Legal outcomes were obtained from courtroom proceedings. The relationship between the outcomes and the circumstances of the case was analyzed by logistic regression.

RESULTS

756 cases were enrolled. 68.3% of the cases involved children under 15 years old. Genital trauma occurred in 6.8% of the girls and 6% of the boys in this group. 31.7% of all the victims were aged 15 years or more. Genital injury was documented in 11.3% of the women. 36.3% of the assailants were convicted. Examination at the request of the police authorities and previous acquaintance of the assailant by the victim were significantly associated with conviction. The presence of general body and/or genital trauma was not associated with conviction.

CONCLUSION

Non-medical variables must be thoroughly collected by the medical examiner. Physical evidence of trauma was neither predictive nor essential for conviction.

Randomised double masked trial comparing the efficacy and tolerance of 0.05% mequitazine eye drops versus 0.05% levocabastine and placebo in allergic conjunctivitis induced by a conjunctival provocation test with Dermatophagoides pteronyssinus

AIM

A double masked randomised trial comparing 0.05% mequitazine eye drops with 0.05% levocabastine and placebo was carried out in otherwise healthy volunteers allergic to house dust mites (Dermatophagoides pteronyssinus).

METHOD

Double masked, randomised, single centre study, comparing three parallel treatment groups. 60 healthy adults with a confirmed history of allergic conjunctivitis to house dust mites for at least 2 years were included and completed the trial. Conjunctival provocation tests (CPT) were done at screening, at visit 2 (V2) (1 week later), and at visit 3 (V3) (2 weeks after V2). Treatment was instilled in the same eye, 5 minutes after the CPT at V2, and twice daily until V3. CPT were scored 5, 10, 15, and 60 minutes after instillation of the dose of Dermatophagoides pteronyssinus antigen determined at inclusion (V2, curative test) or resulting in positivity (V3, preventive test)

RESULTS

In the V2 (curative) test the difference between the active treatments and placebo on the redness+itching scores was not significant. At the V3 (preventive) CPT there was a lower number of reactions at the threshold dose with mequitazine (20%) compared to placebo (60%, p = 0.01) or levocabastine (45%, p = 0.10).

CONCLUSION

This trial failed to clearly demonstrate curative superiority of topical antihistamines with placebo, when a single dose of treatment was instilled following CPT. However mequitazine 0.05% eye drops were superior to placebo in preventing a reaction to CPT, after 2 weeks of treatment.

Nitrate leaching under grassland as affected by mineral nitrogen fertilization and cattle urine

An experiment was performed to better understand to what extent nitrogen fertilization rate and date and amount of urine deposition, when acting in combination, influence nitrate leaching under grassland. Leaching was studied during two successive winters using 2-m2 grassed lysimeters under three levels of N fertilization (0, 150, and 300 kg N ha(-1) yr(-1), referred to as 0N, 150N, and 300N, respectively), two levels of 15N-labeled urine (105 and 165 kg N ha(-1), referred to as A2 and A3, respectively), and three dates of urine application (spring, summer, and fall). During the first winter, total N leaching losses varied between 2 and 50 kg N ha(-1). When tested in combination, N applied as urine to grassland resulted in three times the total N loss by leaching that occurred following N fertilization in the first winter (4.3, 20.8, 34.9, 14.2, 17.1, and 28.7 kg NO3- -N ha(-1) for no urine, A2, A3, ON, 150N, and 300N, respectively). Leaching of 15N urine significantly depended on the date of application: 6.6, 17.3, and 29.1 kg for spring, summer, and fall, respectively. A similar pattern was observed for the contribution of 15N urine to total N leaching with 4.3, 12.9, and 21.4%. However, urine application, both in terms of amount and date, showed very little long-term effect on these N losses in Year 2. In our conditions of low winter rainfall and drainage, grazing management (through season, urinary N amounts, and urine N concentration) resulted in a higher impact on water nitrate quality than moderate N fertilization management.