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BACKGROUND Diabetes mellitus type 2 is often described as the global pandemic of the 21st century with India emerging as its capital. Microvascular complications such as retinopathy associated with diabetes are a serious world health problem, leading to the already existing burden of blindness. The aim of this study was to determine whether VEGF gene polymorphisms rs35569394 and rs699947 are associated with DR in North Indians. MATERIALS AND METHODS North Indian subjects, diabetic controls with no retinopathy (DR I, n = 51), subjects with diabetes with mild-moderate retinal changes (DR II, n = 50), and subjects with diabetes with severe retinopathy with/without retinal neovascularization (DR III, n = 55) were recruited for this study. Genotyping of the VEGF gene I/D polymorphism was done by PCR and C/A polymorphism by PCR-RFLP method. RESULTS DD-genotype was 2.73 times over expressed among DR III category (p = .02; OR: 2.73; 95% CI: 1.20-6.19) as compared to DR I category among male subgroup. C-allele (rs699947) had 1.66-times more exposure among DR III as compared to DR I (C vs. A allele; p = .063; OR: 1.66; 95% CI: 0.97-2.84), probably due to high linkage disequilibrium between both the polymorphisms. CONCLUSIONS Results of our study support the hypothesis that D-allele and DD-genotype of rs35569394 have deleterious effect on the progression of DR. C-allele had skewed frequency towards DR III subjects owing to strong linkage disequilibrium between C-allele (rs699947) and D-allele (rs35569394).

// Gregory Fouquet 1, * , Ingrid Marcq 1, * , Veronique Debuysscher 1 , Jagadeesh Bayry 2 , Amrathlal Rabbind Singh 3 , Abderrahmane Bengrine 4 , Eric Nguyen-Khac 1, 5 , Mickael Naassila 1 and Hicham Bouhlal 1 1 INSERM 1247-GRAP, Centre Universitaire de Recherche en Sante CURS, Universite de Picardie Jules Verne, CHU Sud, Amiens, France 2 INSERM UMRS 1138, Centre de Recherche des Cordeliers–Paris, Paris, France 3 Department of Microbiology, Aravind Medical Research Foundation, Anna Nagar, Madurai-India 4 Biobanque de Picardie, Centre Hospitalier Universitaire Sud, Amiens, France 5 Service Hepato-Gastroenterologie, Centre Hospitalier Universitaire Sud, Amiens, France * These authors contributed equally to this work Correspondence to: Hicham Bouhlal, email: hicham.bouhlal@u-picardie.fr Ingrid Marcq, email: Ingrid.marcq@u-picardie.fr Keywords: SLAMF molecules; cancer; pathophysiology; therapy Received: October 19, 2016 Accepted: December 03, 2017 Epub: February 26, 2018 Published: March 23, 2018 ABSTRACT Signaling Lymphocytic Activation Molecules (SLAM) family receptors are initially described in immune cells. These receptors recruit both activating and inhibitory SH2 domain containing proteins through their Immunoreceptor Tyrosine based Switch Motifs (ITSMs). Accumulating evidence suggest that the members of this family are intimately involved in different physiological and pathophysiological events such as regulation of immune responses and entry pathways of certain viruses. Recently, other functions of SLAM, principally in the pathophysiology of neoplastic transformations have also been deciphered. These new findings may prompt SLAM to be considered as new tumor markers, diagnostic tools or potential therapeutic targets for controlling the tumor progression. In this review, we summarize the major observations describing the implications and features of SLAM in oncology and discuss the therapeutic potential attributed to these molecules.

Growth hormone deficiency affects roughly between one in 3000 and one in 4000 children with most instances of growth hormone deficiency being idiopathic. Growth hormone deficiency can also be associated with genetic diseases or chromosome abnormalities. Association of growth hormone deficiency together with hypothalamic-pituitary axis malformation and Cat-Eye syndrome is a very rare condition. We report a family with two brothers presenting with growth delay due to a growth hormone deficiency associated with a polymalformation syndrome. They both displayed pre-auricular pits and tags, imperforate anus and Duane retraction syndrome. Both parents and a third unaffected son displayed normal growth pattern. Cerebral MRI showed a hypothalamic-pituitary axis malformation in the two affected brothers. Cytogenetic studies revealed a type I small supernumerary marker chromosome derived from chromosome 22 resulting in a tetrasomy 22pter-22q11.21 characteristic of the Cat-Eye syndrome. The small supernumerary marker chromosome was present in the two affected sons and the mother in a mosaic state. Patients with short stature due to growth hormone deficiency should be evaluated for chromosomal abnormality. Family study should not be underestimated.

Stormorken syndrome is a rare autosomal dominant disorder characterized by a phenotype that includes miosis, thrombocytopenia/thrombocytopathy with bleeding time diathesis, intellectual disability, mild hypocalcemia, muscle fatigue, asplenia, and ichthyosis. Using targeted sequencing and whole-exome sequencing, we identified the c.910CT transition in a STIM1 allele (p.R304W) only in patients and not in their unaffected family members. STIM1 encodes stromal interaction molecule 1 protein (STIM1), which is a finely tuned endoplasmic reticulum Ca(2+) sensor. The effect of the mutation on the structure of STIM1 was investigated by molecular modeling, and its effect on function was explored by calcium imaging experiments. Results obtained from calcium imaging experiments using transfected cells together with fibroblasts from one patient are in agreement with impairment of calcium homeostasis. We show that the STIM1 p.R304W variant may affect the conformation of the inhibitory helix and unlock the inhibitory state of STIM1. The p.R304W mutation causes a gain of function effect associated with an increase in both resting Ca(2+) levels and store-operated calcium entry. Our study provides evidence that Stormorken syndrome may result from a single-gene defect, which is consistent with Mendelian-dominant inheritance.

Most adults affected with hereditary hemochromatosis are homozygous for a single point mutation of HFE (p.Cys282Tyr). Apart from the compound heterozygous state for the p.Cys282Tyr mutant and the widespread p.His63Asp variant allele, other rare HFE mutations can be found in trans and may have clinical impact. In the present report we describe the structural and functional consequences of a new mutation, namely the p.Arg226Gly which was inherited in trans with the p.Cys282Tyr allele in a patient affected with a mild iron overload. Because the R226G substitution is located in the vicinity of the normal Cys225S–S282Cys disulfide bond we initially investigated the structure of the variant by molecular dynamics techniques in order to estimate the effect of the mutation on the global structure of HFE domain α3. We found that the solvation free energy, hydrophobicity and formation of salt bridges are slightly modified with the global secondary structure of the α3 domain being conserved. In a previous paper, we demonstrated that the Q283P substitution leads to the loss of the normal Cys225S–S282Cys disulfide bridge. Similar to the Q283P substitution, the R226G substitution does not substitute a residue directly involved in the formation of the disulfide bridge. However, unlike the p.Gln283Pro variant which destroyed the normal disulfide bridge, the R226G mutation does not affect the normal Cys225S–S282Cys bridge. Furthermore based on cell line studies we clearly show that the mutation does not prevent cell surface localization, β2-microglobulin association and binding to transferrin receptor 1. This new compound heterozygous phenotype is very close to those of the C282Y/H63D compound heterozygous patients who display the biochemical hemochromatosis phenotype but with lower body iron stores than C282Y homozygotes. Our results do not exclude unknown genetic and/or metabolic factors that may act synergistically to increase the ferritin level.

Pre-BCR acts as a critical checkpoint in B cell development. However, its signalling cascade still remains indistinctly characterised in human. We investigated pre-BCR signalling pathway to examine its regulation in normal primary pre-B lymphocytes and pre-B cell lines. In cell lines, early signalling events occurring after pre-BCR stimulation include phosphorylation of Lyn, Blk and Syk together with ZAP70, Btk, Vav, PLC-γ2 and various adaptor proteins, such as BLNK, LAB, LAT and SLP-76. Further downstream, these molecules induced activation of the PI3K/AKT and MAP-kinase resulting in an augmentation of canonical NF-κB pathways and cFos/AP1 activation. PI3K and MAPK exerted opposing effects on the pre-BCR-induced activation of the canonical NF-κB and c-Fos/AP1 pathways. Immediate nuclear export of FoxO3A and delayed import of IRF4 were additional events observed after pre-BCR crosslinking in primary cells. Pre-BCR-induced down-regulation of Rag1, Rag2, E2A and Pax5 transcripts occurred in a PI3K-dependent manner. Finally we bring evidence that pre-BCR stimulation or co stimulation with CD19 enhances cell cycle signal.

// Hicham Bouhlal 1, 2 , Hakim Ouled-Haddou 1, * , Veronique Debuysscher 1, * , Amrathlal Rabbind Singh 1 , Christele Ossart 1, 2 , Aline Reignier 1, 2 , Hakim Hocini 3 , Gregory Fouquet 1 , Mohammed Al Baghami 1, 2 , Melanie Simoes Eugenio 1 , Eric Nguyen-Khac 4 , Jean-Marc Regimbeau 5 , Ingrid Marcq 1 1 Centre Universitaire de Recherche en Sante CURS, CAP-Sante (FED 4231), Universite de Picardie Jules Verne, CHU Sud, Amiens, France 2 Service d’Hematologie Clinique et de Therapie Cellulaire Centre Hospitalier Universitaire Sud, Amiens, France 3 IMRB, Equipe 16, Genomique Medicale, UFR de Medecine, Creteil, France 4 Service Hepato-Gastroenterologie, Centre Hospitalier Universitaire Sud, Amiens, France 5 Service de Chirurgie Digestive Centre Hospitalier Universitaire Sud, Amiens, France * These authors contributed equally to this work Correspondence to: Hicham Bouhlal, e-mail: hicham.bouhlal@u-picardie.fr Amrathlal Rabbind Singh, e-mail: rabbind@gmail.com Ingrid Marcq, e-mail: ingrid.marcq@u-picardie.fr Keywords: SLAMF3, HCC, retinoblastoma factor RB, polo-like kinase 1 (PLK1), mitosis Received: June 18, 2015 Accepted: December 09, 2015 Published: January 20, 2016 ABSTRACT Polo-like kinase PLK1 is a cell cycle protein that plays multiple roles in promoting cell cycle progression. Among the many roles, the most prominent role of PLK1 is to regulate the mitotic spindle formation checkpoint at the M-phase. Recently we reported the expression of SLAMF3 in Hepatocytes and show that it is down regulated in tumor cells of hepatocellular carcinoma (HCC). We also show that the forced high expression level of SLAMF3 in HCC cells controls proliferation by inhibiting the MAPK ERK/JNK and the mTOR pathways. In the present study, we provide evidence that the inhibitory effect of SLAMF3 on HCC proliferation occurs through Retinoblastoma (RB) factor and PLK1-dependent pathway. In addition to the inhibition of MAPK ERK/JNK and the mTOR pathways, expression of SLAMF3 in HCC retains RB factor in its hypophosphorylated active form, which in turn inactivates E2F transcription factor, thereby repressing the expression and activation of PLK1. A clear inverse correlation was also observed between SLAMF3 and PLK expression in patients with HCC. In conclusion, the results presented here suggest that the tumor suppressor potential of SLAMF3 occurs through activation of RB that represses PLK1. We propose that the induction of a high expression level of SLAMF3 in cancerous cells could control cellular mitosis and block tumor progression.

We have identified a deletion of 125 bp (α-α(Δ125)) (NG_000006.1: g.37040_37164del) in the α-globin gene cluster in a Kabyle population. A combination of singlex and multiplex polymerase chain reaction (PCR)-based assays have been used to identify the molecular defect. Sequencing of the abnormal PCR amplification product revealed a novel α1-globin promoter deletion. The endpoints of the deletion were characterized by sequencing the deletion junctions of the mutated allele. The observed deletion was located 378 bp upstream of the α1-globin gene transcription initiation site and leaves the α2 gene intact. In some patients, the α-α(Δ125) deletion was shown to segregate with Hb S (HBB: c.20A>T) and/or Hb C (HBB: c.19G>A) or a β-thalassemic allele. The α-α(Δ125) deletion has no discernible effect on red cell indices when inherited with no other abnormal globin genes. The family study demonstrated that the deletion is heritable. This is the only example of an intergenic α2-α1 non coding DNA deletion, leaving the α2-globin gene and the α1 coding part intact.

International audience; Multidrug resistance MDR proteins (MRPs) are members of the C family of a group of proteins named ATP binding cassette (ABC) transporters. MRPs can transport drugs including anticancer drugs, nucleoside analogs, antimetabolites and tyrosine kinase inhibitors. Drugs used in HCC therapy, such as tyrosine kinase inhibitor sorafenib, are substrates of uptake and/or efflux transporters. Variable expression of MRPs at the plasma membrane of tumor cells may contribute to drug resistance and subsequent clinical response. Recently, we reported that the hepatocyte SLAMF3 expression (Signaling Lymphocytic Activation Molecule Family member 3) was reduced in tumor cells from hepatocellular carcinoma (HCC) compared to its high expression in adjacent tissues. In the present study, we make a strong correlation between induced SLAMF3 overexpression and the specific loss of MRP-1 expression and its functionalities as a drugs resistance transporter. No changes were observed on expression of ABCG2 and MDR. More importantly, we highlight a strong inverse correlation between MRP-1 and SLAMF3 expression in patients with HCC. We propose that the SLAMF3 overexpression in cancerous cells could represent a potential therapeutic strategy to improve the drugs sensibility of resistant cells and thus control the therapeutic failure in HCC patients.

// Hussein Ghamlouch 1, 2, 5 , Walaa Darwiche 3 , Ahmed Hodroge 1 , Hakim Ouled-Haddou 1 , Sebastien Dupont 1, 5 , Amrathlal Rabbind Singh 1 , Caroline Guignant 1, 2 , Stephanie Trudel 1, 4 , Bruno Royer 1, 5 , Brigitte Gubler 1, 2, 4, * , Jean-Pierre Marolleau 1, 5, * 1 EA4666, LNPC, Universite de Picardie Jules Verne, Amiens, France 2 Department of Immunology, Amiens University Medical Center, Amiens, France 3 PeriTox, Perinatalite & Risques Toxiques, UMR-I 01 Unite mixte INERIS, Amiens, France 4 Department of Molecular Oncobiology, Amiens University Medical Center, Amiens, France 5 Department of Clinical Hematology and Cell Therapy, Amiens University Medical Center, Amiens, France * These authors have contributed equally to this work Correspondence to: Hussein Ghamlouch, e-mail: hussein.ghamlouch@hotmail.com Jean-Pierre Marolleau, e-mail: marolleau.jean-pierre@chu-amiens.fr Keywords: chronic lymphocytic leukemia, B-cell differentiation, apoptosis, LEF1, ROR1 Received: March 10, 2015 Accepted: April 28, 2015 Published: May 11, 2015 ABSTRACT Recent research has shown that chronic lymphocytic leukemia (CLL) B-cells display a strong tendency to differentiate into antibody-secreting cells (ASCs) and thus may be amenable to differentiation therapy. However, the effect of this differentiation on factors associated with CLL pathogenesis has not been reported. In the present study, purified CLL B-cells were stimulated to differentiate into ASCs by phorbol myristate acetate or CpG oligodeoxynucleotide, in combination with CD40 ligand and cytokines in a two-step, seven-day culture system. We investigated (i) changes in the immunophenotypic, molecular, functional, morphological features associated with terminal differentiation into ASCs, (ii) the expression of factors involved in CLL pathogenesis, and (iii) the expression of pro- and anti-apoptotic proteins in the differentiated cells. Our results show that differentiated CLL B-cells are able to display the transcriptional program of ASCs. Differentiation leads to depletion of the malignant program and deregulation of the apoptosis/survival balance. Analysis of apoptosis and the cell cycle showed that differentiation is associated with low cell viability and a low rate of cell cycle entry. Our findings shed new light on the potential for differentiation therapy as a part of treatment strategies for CLL.

Pre-BCR acts as a critical checkpoint in B cell development. However, its signalling cascade still remains indistinctly characterised in human. We investigated pre-BCR signalling pathway to examine its regulation in normal primary pre-B lymphocytes and pre-B cell lines. In cell lines, early signalling events occurring after pre-BCR stimulation include phosphorylation of Lyn, Blk and Syk together with ZAP70, Btk, Vav, PLC-γ2 and various adaptor proteins, such as BLNK, LAB, LAT and SLP-76. Further downstream, these molecules induced activation of the PI3K/AKT and MAP-kinase resulting in an augmentation of canonical NF-κB pathways and cFos/AP1 activation. PI3K and MAPK exerted opposing effects on the pre-BCR-induced activation of the canonical NF-κB and c-Fos/AP1 pathways. Immediate nuclear export of FoxO3A and delayed import of IRF4 were additional events observed after pre-BCR crosslinking in primary cells. Pre-BCR-induced down-regulation of Rag1, Rag2, E2A and Pax5 transcripts occurred in a PI3K-dependent manner. Finally we bring evidence that pre-BCR stimulation or co stimulation with CD19 enhances cell cycle signal.

Computational analysis of sequence homology of the chiSRC gene cluster, encoding a chitinase in Streptomyces peucetius, showed that the gene cluster could be a two-component regulon comprising a sensor kinase (chiS) and a response regulator (chiR). To prove that the ChiSRC is an authentic two-component system, the chiS gene was cloned and expressed in E.coli and the purified protein was used for biochemical analysis. In this report, we provide biochemical evidence to show that the sensor kinase encoded by chiS gene indeed is a histidine kinase capable of autophosphorylation and the histidine 144 residue of the ChiS protein is the phosphate acceptor. An insertion mutation at the chiS locus led to overproduction chitinase protein in S. peucetius implying that the chiC gene is negatively regulated by the two-component system.