Fabrizio Scatena

Isolation and expansion of equine umbilical cord-derived matrix cells (EUCMCs)

Stem cells from extra‐embryonic sources can be obtained by non‐invasive procedures. We have standardized a method for the expansion of equine umbilical cord‐derived matrix cells (EUCMCs) for potential therapy.

Human Glioblastoma Multiforme: p53 Reactivation by a Novel MDM2 Inhibitor

Cancer development and chemo-resistance are often due to impaired functioning of the p53 tumor suppressor through genetic mutation or sequestration by other proteins. In glioblastoma multiforme (GBM), p53 availability is frequently reduced because it binds to the Murine Double Minute-2 (MDM2) oncoprotein, which accumulates at high concentrations in tumor cells. The use of MDM2 inhibitors that interfere with the binding of p53 and MDM2 has become a valid approach to inhibit cell growth in a number of cancers; however little is known about the efficacy of these inhibitors in GBM. We report that a new small-molecule inhibitor of MDM2 with a spirooxoindolepyrrolidine core structure, named ISA27, effectively reactivated p53 function and inhibited human GBM cell growth in vitro by inducing cell cycle arrest and apoptosis. In immunoincompetent BALB/c nude mice bearing a human GBM xenograft, the administration of ISA27 in vivo activated p53, inhibited cell proliferation and induced apoptosis in tumor tissue. Significantly, ISA27 was non-toxic in an in vitro normal human cell model and an in vivo mouse model. ISA27 administration in combination with temozolomide (TMZ) produced a synergistic inhibitory effect on GBM cell viability in vitro, suggesting the possibility of lowering the dose of TMZ used in the treatment of GBM. In conclusion, our data show that ISA27 releases the powerful antitumor capacities of p53 in GBM cells. The use of this MDM2 inhibitor could become a novel therapy for the treatment of GBM patients.

PK 11195 differentially affects cell survival in human wild-type and 18 kDa translocator protein-silenced ADF astrocytoma cells†

Gliomas are the most common brain tumours with a poor prognosis due to their aggressiveness and propensity for recurrence. The 18 kDa translocator protein (TSPO) has been demonstrated to be greatly expressed in glioma cells and its over‐expression has been correlated with glioma malignance grades. Due to both its high density in tumours and the pro‐apoptotic activity of its ligands, TSPO has been suggested as a promising target in gliomas. With the aim to evidence if the TSPO expression level alters glioma cell susceptibility to undergo to cell death, we analysed the effects of the specific TSPO ligand, PK 11195, in human astrocytoma wild‐type and TSPO‐silenced cell lines. As first step, TSPO was characterised in human astrocytoma cell line (ADF). Our data demonstrated the presence of a single class of TSPO binding sites highly expressed in mitochondria. PK 11195 cell treatment activated an autophagic pathway followed by apoptosis mediated by the modulation of the mitochondrial permeability transition. In TSPO‐silenced cells, produced by siRNA technique, a reduced cell proliferation rate and a decreased cell susceptibility to the PK 11195‐induced anti‐proliferative effect and mitochondrial potential dissipation were demonstrated respect to control cells. In conclusion, for the first time, PK 11195 was demonstrated to differentially affect glioma cell survival in relation to TSPO expression levels. These results encourage the development of specific‐cell strategies for the treatment of gliomas, in which TSPO is highly expressed respect to normal cells. J. Cell. Biochem. 105: 712–723, 2008.

Different media and supplements modulate the clonogenic and expansion properties of rabbit bone marrow mesenchymal stem cells

Background -Rabbits provide an excellent model for many animal and human diseases, such as cardiovascular diseases, for the development of new vaccines in wound healing management and in the field of tissue engineering of tendon, cartilage, bone and skin.The study presented herein aims to investigate the biological properties of bone marrow rabbit MSCs cultured in different conditions, in order to provide a basis for their clinical applications in veterinary medicine.Findings -MSCs were isolated from 5 New Zealand rabbits. Fold increase, CFU number, doubling time, differentiation ability and immunophenotype were analyzed.With the plating density of 10 cells/cm2 the fold increase was significantly lower with DMEM-20%FCS and MSCs growth was significantly higher with αMEM-hEGF. The highest clonogenic ability was found at 100 cell/cm2 with MSCBM and at 10 cell/cm2 with M199. Both at 10 and 100 cells/cm2, in αMEM medium, the highest CFU increase was obtained by adding bFGF. Supplementing culture media with 10%FCS-10%HS determined a significant increase of CFU.Conclusion -Our data suggest that different progenitor cells with differential sensitivity to media, sera and growth factors exist and the choice of culture conditions has to be carefully considered for MSC management.

The role of anti-HLA antibodies in hematopoietic stem cell transplantation.

Donor-specific antihuman leukocyte antigen antibodies (DSHA) have been clearly implicated in graft rejection in solid organ transplantation. Their role in allogeneic hematopoietic stem-cell transplantation (allo-HSCT) remains unclear. We summarize here evidence supporting a role for DSHA in graft failure in animal models of allo-HSCT and in clinical settings whenever no full HLA matching occurs.

PIGA (N,N-Di-n-butyl-5-chloro-2-(4-chlorophenyl)indol-3-ylglyoxylamide), a new mitochondrial benzodiazepine-receptor ligand, induces apoptosis in C6 glioma cells

Mitochondrial benzodiazepine‐receptor (mBzR) ligands constitute a heterogeneous class of compounds that show a pleiotropic spectrum of effects within the cells, including the modulation of apoptosis. In this paper, a novel synthetic 2‐phenylindol‐3‐ylglyoxylamide derivative, N,N‐di‐n‐butyl‐5‐chloro‐2‐(4‐chlorophenyl)indol‐3‐ylglyoxylamide (PIGA), which shows high affinity and selectivity for the mBzR, is demonstrated to induce apoptosis in rat C6 glioma cells. PIGA was able to dissipate mitochondrial transmembrane potential (ΔΨm) and to cause a significant cytosolic accumulation of cytochrome c. Moreover, typical features of apoptotic cell death, such as caspase‐3 activation and DNA fragmentation, were also detected in PIGA‐treated cells. Our data expand the knowledge on mBzR ligand‐mediated apoptosis and suggest PIGA as a novel proapoptotic compound with therapeutic potential against glial tumours, in which apoptosis resistance has been reported to be involved in carcinogenesis.

Hypnotizability and Catechol-O-Methyltransferase (COMT) polymorphysms in Italians

Higher brain dopamine content depending on lower activity of Catechol-O-Methyltransferase (COMT) in subjects with high hypnotizability scores (highs) has been considered responsible for their attentional characteristics. However, the results of the previous genetic studies on association between hypnotizability and the COMT single nucleotide polymorphism (SNP) rs4680 (Val158Met) were inconsistent. Here, we used a selective genotyping approach to re-evaluate the association between hypnotizability and COMT in the context of a two-SNP haplotype analysis, considering not only the Val158Met polymorphism, but also the closely located rs4818 SNP. An Italian sample of 53 highs, 49 low hypnotizable subjects (lows), and 57 controls, were genotyped for a segment of 805 bp of the COMT gene, including Val158Met and the closely located rs4818 SNP. Our selective genotyping approach had 97.1% power to detect the previously reported strongest association at the significance level of 5%. We found no evidence of association at the SNP, haplotype, and diplotype levels. Thus, our results challenge the dopamine-based theory of hypnosis and indirectly support recent neuropsychological and neurophysiological findings reporting the lack of any association between hypnotizability and focused attention abilities.

Real-Time Quantitative Polymerase Chain Reaction Analysis of Patients With Refractory Chronic Periodontitis

BACKGROUND Periodontitis is a complex multifactorial disease and is typically polygenic in origin. Genes play a fundamental part in each biologic process forming complex networks of interactions. However, only some genes have a high number of interactions with other genes in the network and may, therefore, be considered to play an important role. In a preliminary bioinformatic analysis, five genes that showed a higher number of interactions were identified and termed leader genes. In the present study, we use real-time quantitative polymerase chain reaction (PCR) technology to evaluate the expression levels of leader genes in the leukocytes of 10 patients with refractory chronic periodontitis and compare the expression levels with those of the same genes in 24 healthy patients. METHODS Blood was collected from 24 healthy human subjects and 10 patients with refractory chronic periodontitis and placed into heparinized blood collection tubes by personnel trained in phlebotomy using a sterile technique. Blood leukocyte cells were immediately lysed by using a kit for total RNA purification from human whole blood. Complementary DNA (cDNA) synthesis was obtained from total RNA and then real-time quantitative PCR was performed. PCR efficiencies were calculated with a relative standard curve derived from a five cDNA dilution series in triplicate that gave regression coefficients >0.98 and efficiencies >96%. The standard curves were obtained using glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and growth factor receptor binding protein 2 (GRB2), casitas B-lineage lymphoma (CBL), nuclear factor-KB1 (NFKB1), and REL-A (gene for transcription factor p65) gene primers and amplified with 1.6, 8, 40, 200, and 1,000 ng/μL total cDNA. Curves obtained for each sample showed a linear relationship between RNA concentrations and the cycle threshold value of real-time quantitative PCR for all genes. Data were expressed as mean ± SE (SEM). The groups were compared to the analysis of variance. A probability value <0.01 was considered statistically significant. RESULTS The present study agrees with the preliminary bioinformatics analysis. In our experiments, the association of pathology with the genes was statistically significant for GRB2 and CBL (P <0.01), and it was not statistically significant for REL-A and NFKB1. CONCLUSION This article lends support to our preliminary hypothesis that assigned an important role in refractory aggressive periodontitis to leader genes.

A novel HLA‐DRB1 allele, DRB1*01:54, identified by sequence‐based typing

The new HLA DRB1*01:54 differs from DRB1*01:02:01 by one nucleotide at exon 2.

Promoter polymorphisms of the NOS3 gene are associated with hypnotizability-dependent vascular response to nociceptive stimulation

Hypnotizability is associated with a few physiological characteristics also in the normal awake state. Differences in flow-mediated dilation (FMD) have been observed in subjects with high (Highs) or low (Lows) hypnotizability during nociceptive stimulation. FMD is largely due to the nitric oxide (NO) produced by vascular endothelium through the activity of NO synthase (eNOS). Endothelial NOS is encoded by the NOS3 locus. Aim of this pilot study was to investigate the association between genetic polymorphisms of NOS3 involved in NO blood levels and hypnotizability. Nine single nucleotide polymorphisms (SNPs) of the NOS3 gene were analyzed in the DNA of 24 Highs, 22 Lows, and 61 newborns. Two SNPs, rs1800783 (-1474 T/A) and rs2070744 (-786 T/C), located in the upstream and promoter region of the gene, respectively, showed significant differences between Highs and Lows in allele frequency. Haplotype analysis showed that the newborns were in linkage equilibrium for these SNPs, whereas both Highs and Lows showed linkage disequilibrium. The A-C haplotype (associated with lower NO availability in the general population) was more frequent in Highs, and the T-T haplotype was more frequent in Lows. Thus, the lower FMD reduction observed in Highs during nociceptive stimulation, which is indicative of higher NO availability, should be due to greater efficacy of shear stress-related transcriptional factors and/or to lower effects of NOS inhibitory controls. A consequent theoretical proposal concerns the possible role of NO in the brain vessels where, in stimulation conditions, NO diffusion to the extracellular compartment might be involved in hypnotic responding.