Mariarosa Melone | Università della Campania Luigi Vanvitelli (original) (raw)

Papers by Mariarosa Melone

Research paper thumbnail of The ADAMTS18 gene is responsible for autosomal recessive early onset severe retinal dystrophy

Orphanet Journal of Rare Diseases, 2013

Background: Inherited retinal dystrophies, including Retinitis Pigmentosa and Leber Congenital Am... more Background: Inherited retinal dystrophies, including Retinitis Pigmentosa and Leber Congenital Amaurosis among others, are a group of genetically heterogeneous disorders that lead to variable degrees of visual deficits. They can be caused by mutations in over 100 genes and there is evidence for the presence of as yet unidentified genes in a significant proportion of patients. We aimed at identifying a novel gene for an autosomal recessive form of early onset severe retinal dystrophy in a patient carrying no previously described mutations in known genes.

Research paper thumbnail of Alessio et al. 2018 Muse OT_044397_preprint.pdf

Research paper thumbnail of Phosphodiesterase 10A (PDE10A) localization in the R6/2 mouse model of Huntington's disease

Neurobiology of Disease, 2013

Research paper thumbnail of Autosomal dominant hereditary spastic paraplegia: report of a large italian family with R581X spastin mutation

Neurological Sciences, 2007

ABSTRACT We describe a large kindred with a typical pure form of autosomal dominant hereditary sp... more ABSTRACT We describe a large kindred with a typical pure form of autosomal dominant hereditary spastic paraplegia (ADHSP). On the basis of maximum LOD score of 1.94 at theta (max)=0 with marker D2S367, we obtained suggestive evidence for linkage of ADHSP to SPG4 locus. Denaturing high-performance liquid chromatography (DHPLC) and direct sequence analysis allowed us to identify a nonsense mutation (1741* C>T) in exon 17 of the Spastin gene. This transition, carried by all the affected family members and two apparently healthy individuals, lead to truncation of the last 36 amino acids in the C-terminus of the protein. These results confirm the existence of mutation in the SPG4 gene with a reduced penetrance, indicating that other genetic or environmental factors are required to trigger full-blown disease.

Research paper thumbnail of Changes in the expression of extracellular regulated kinase (ERK 1/2) in the R6/2 mouse model of Huntington's disease after phosphodiesterase IV inhibition

Neurobiology of Disease, 2012

immunohistochemistry ERK rolipram Huntington's disease R6/2 The mitogen-activated protein kinases... more immunohistochemistry ERK rolipram Huntington's disease R6/2 The mitogen-activated protein kinases (MAPKs) superfamily comprises three major signaling pathways: the extracellular signal-regulated protein kinases (ERKs), the c-Jun N-terminal kinases or stress-activated protein kinases (JNKs/SAPKs) and the p38 family of kinases. ERK 1/2 signaling has been implicated in a number of neurodegenerative disorders, including Huntington's disease (HD). Phosphorylation patterns of ERK 1/2 and JNK are altered in cell models of HD. In this study, we aimed at studying the correlations between ERK 1/2 and the neuronal vulnerability to HD degeneration in the R6/2 transgenic mouse model of HD. Single and double-label immunofluorescence for phospho-ERK (pERK, the activated form of ERK) and for each of the striatal neuronal markers were employed on perfusion-fixed brain sections from R6/2 and wild-type mice. Moreover, Phosphodiesterase 4 inhibition through rolipram was used to study the effects on pERK expression in the different types of striatal neurons. We completed our study with western blot analysis. Our study shows that pERK levels increase with age in the medium spiny striatal neurons and in the parvalbumin interneurons, and that rolipram counteracts such increase in pERK. Conversely, cholinergic and somatostatinergic interneurons of the striatum contain higher levels of pERK in the R6/2 mice compared to the controls. Rolipram induces an increase in pERK expression in these interneurons. Thus, our study confirms and extends the concept that the expression of phosphorylated ERK 1/2 is related to neuronal vulnerability and is implicated in the pathophysiology of cell death in HD.

Research paper thumbnail of Myotonic Dystrophy: Antisense Oligonucleotide Inhibition of DMPK Gene Expression in Vitro

Biochemical and Biophysical Research Communications, 1996

Antisense phosphorothioate oligonucleotides, targeted against the first codon starting region of ... more Antisense phosphorothioate oligonucleotides, targeted against the first codon starting region of DMPK mRNA, were successfully used in K562 and HepG2 cells to decrease DMPK expression. The most effective antisense oligo, MIO1, when added to K562 cells, shows a 75% reduction of the DMPK gene expression 6 hours after addition. The same molecule, when encapsulated in liposomes, delays myotonin mRNA decrease

Research paper thumbnail of MRI "fogging" in cerebellar ischaemia: case report

Neuroradiology, 1997

Subacute cerebral infarcts may appear normal on T2-weighted MRI as an area isointense with surrou... more Subacute cerebral infarcts may appear normal on T2-weighted MRI as an area isointense with surrounding normal tissue. This MRI "fogging effect" has been described in only a few cases. We present a further case of fogging observed during the evolution of a cerebellar infarct.

Research paper thumbnail of Modulation of cytokine production in activated human monocytes by somatostatin

Neuropeptides, 1996

The immunosuppressor effects of the widely distributed neuropeptide somatostatin were examined on... more The immunosuppressor effects of the widely distributed neuropeptide somatostatin were examined on purified peripheral blood human monocytes. Somatostatin, at concentrations thought to be physiologic (10−10−10−7 M), regulated monocyte/macrophage responses to (LPS) stimulation, as reflected by interleukin production. In particular, somatostatin had direct inhibitory effects on TNF-α, IL-1β, and IL-6 secretion by LPS-activated monocytes, while the decrease on IL-8 synthesis was

Research paper thumbnail of Revelation of a New Mitochondrial DNA Mutation (G12147A) in a MELAS/MERFF Phenotype

Archives of Neurology, 2004

A 26-year-old man presented at onset with the syndrome of mitochondrial encephalomyopathy, lactic... more A 26-year-old man presented at onset with the syndrome of mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes (MELAS) and later with a phenotype for MELAS and myoclonic epilepsy and ragged red fiber disease (MELAS/MERRF). To identify the possible defects in the mitochondrial genome in blood and muscle samples of the patient. Case study of a patient clinically exhibiting strokelike episodes and then epilepsy with myoclonic features, ataxia, and dementia. Research unit of a university hospital. Electromyographic, morphologic, and biochemical studies of muscle and molecular analysis of blood and muscle to investigate mitochondrial DNA (mtDNA) size and quantity. Morphologically, we found abnormal mitochondrial proliferation with several cytochrome-c oxidase (COX)-negative fibers in muscle biopsy specimens; the analysis of serial sections showed a decreased immunoreactivity for the mtDNA-encoded subunits COXII and, partially, COXI. Biochemically, we found a partial and isolated COX deficiency. The complete mtDNA sequence analysis identified 3 sequence changes, 2 of which were reported polymorphisms. The remaining change, a G12147A transition in the transfer RNA(His) gene, appeared to be the likely pathogenic mutation. Our data propose that the G12147A change, the first mutation in the transfer RNA(His) gene associated with an overlapped MELAS/MERFF phenotype, is the cause of the encephalomyopathy in this patient interfering with the overall mitochondrial protein synthesis.

Research paper thumbnail of Abnormal accumulation of tTGase products in muscle and erythrocytes of chorea-acanthocytosis patients

Journal of neuropathology and experimental neurology, 2002

Chorea-Acanthocytosis (CHAC) is an autosomal recessive disease characterized by neurodegeneration... more Chorea-Acanthocytosis (CHAC) is an autosomal recessive disease characterized by neurodegeneration and acanthocytosis. Enhanced creatine kinase concentration is a constant feature of the condition. The mechanism underlying CHAC is unknown. However, acanthocytosis and enhanced creatine kinase suggest a protein defect that deranges the membrane-cytoskeleton interface in erythrocytes and muscle, thereby resulting in neurodegeneration. Acanthocytes have been correlated with structural and functional changes in membrane protein band 3--a ubiquitous anion transporter. Residue Gln-30 of band 3 serves as a membrane substrate for tissue transglutaminase (tTGase), which belongs to a class of intra- and extra-cellular Ca2+-dependent cross-linking enzymes found in most vertebrate tissues. In an attempt to cast light on the pathophysiology of CHAC, we used reverse-phase HPLC and immunohistochemistry to evaluate the role of tTGase in this disorder. We found increased amounts of tTGase-derived N(ep...

Research paper thumbnail of pRb2/p130 gene overexpression induces astrocyte differentiation

Molecular and cellular neurosciences, 2001

There are many data on the activity of the RB gene in neural differentiation and apoptosis, but t... more There are many data on the activity of the RB gene in neural differentiation and apoptosis, but the role of pRb2/p130 in neuronal and glial maturation has been far less investigated. To elucidate the role of pRb2/p130 in astrocyte development we overexpressed this protein in astrocytoma and normal astrocyte cultures by adenoviral-mediated gene transfer. In astrocytoma cells, p130/RB2 overexpression resulted in a significant reduction of cell growth and in an increased G(0)/G(1) cell population. We did not observe any induction of programmed cell death as determined by TUNEL reaction. Interestingly, pRb2/p130 overexpression induced astrocyte differentiation. Astrocyte cell cycle arrest and differentiation seemed to proceed through a way distinct from the p53 pathway.

Research paper thumbnail of Ruta graveolens L. Induces Death of Glioblastoma Cells and Neural Progenitors, but Not of Neurons, via ERK 1/2 and AKT Activation

PLOS ONE, 2015

Glioblastoma multiforme is a highly aggressive brain tumor whose prognosis is very poor. Due to e... more Glioblastoma multiforme is a highly aggressive brain tumor whose prognosis is very poor. Due to early invasion of brain parenchyma, its complete surgical removal is nearly impossible, and even after aggressive combined treatment (association of surgery and chemo- and radio-therapy) five-year survival is only about 10%. Natural products are sources of novel compounds endowed with therapeutic properties in many human diseases, including cancer. Here, we report that the water extract of Ruta graveolens L., commonly known as rue, induces death in different glioblastoma cell lines (U87MG, C6 and U138) widely used to test novel drugs in preclinical studies. Ruta graveolens' effect was mediated by ERK1/2 and AKT activation, and the inhibition of these pathways, via PD98058 and wortmannin, reverted its antiproliferative activity. Rue extract also affects survival of neural precursor cells (A1) obtained from embryonic mouse CNS. As in the case of glioma cells, rue stimulates the activation of ERK1/2 and AKT in A1 cells, whereas their blockade by pharmacological inhibitors prevents cell death. Interestingly, upon induction of differentiation and cell cycle exit, A1 cells become resistant to rue's noxious effects but not to those of temozolomide and cisplatin, two alkylating agents widely used in glioblastoma therapy. Finally, rutin, a major component of the Ruta graveolens water extract, failed to cause cell death, suggesting that rutin by itself is not responsible for the observed effects. In conclusion, we report that rue extracts induce glioma cell death, discriminating between proliferating/undifferentiated and non-proliferating/differentiated neurons. Thus, it can be a promising tool to isolate novel drugs and also to discover targets for therapeutic intervention.

Research paper thumbnail of High grade glioblastoma is associated with aberrant expression of ZFP57, a protein involved in gene imprinting, and of CPT1A and CPT1C that regulate fatty acid metabolism

Cancer Biology & Therapy, 2014

The diagnosis of glioblastoma is still based on tumor histology, but emerging molecular diagnosis... more The diagnosis of glioblastoma is still based on tumor histology, but emerging molecular diagnosis is becoming an important part of glioblastoma classification. Besides the well-known cell cycle-related circuitries that are associated with glioblastoma onset and development, new insights may be derived by looking at pathways involved in regulation of epigenetic phenomena and cellular metabolism, which may both be highly deregulated in cancer cells. We evaluated if in glioblastoma patients the high grade of malignancy could be associated with aberrant expression of some genes involved in regulation of epigenetic phenomena and lipid metabolism. We measured the mRNA levels of ZFP57, TRIM28, CPT1A, CPT1B, and CPT1C in a cohort of 80 patients divided in two groups: grade II and grade IV. We evidenced that high grade glioblastoma is associated with increased level of ZFP57, a protein involved in gene imprinting, and aberrant expression of CPT1A and CPT1C, regulators of fatty acid oxidation. Our study may pave the way to identify new markers that could be potentially useful for diagnosis and/or prognosis of glioblastoma.

Research paper thumbnail of Genes involved in regulation of stem cell properties: studies on their expression in a small cohort of neuroblastoma patients

Cancer biology & therapy, 2009

Cancer stem cells have been isolated from many tumors. Several evidences prove that neuroblastoma... more Cancer stem cells have been isolated from many tumors. Several evidences prove that neuroblastoma contains its own stem cell-like cancer cells. We chose to analyze 20 neuroblastoma tumor samples in the expression of 13 genes involved in the regulation of stem cell properties to evaluate if their misregulation could have a clinical relevance. In several specimens we detected the expression of genes belonging to the OCT3/SOX2/NANOG/KLF4 core circuitry that acts at the highest level in regulating stem cell biology. This result is in agreement with studies showing the existence of malignant stem cells in neuroblastoma. We also observed differences in the expression of some stemness-related genes that may be useful for developing new prognostic analyses. In fact, preliminary data suggests that the presence/absence of UTF1 along with differences in BMI1 mRNA levels could distinguish low grade neuroblastomas from IV stage tumors.

Research paper thumbnail of Silencing of RB1 and RB2/P130 during adipogenesis of bone marrow stromal cells results in dysregulated differentiation

Cell cycle (Georgetown, Tex.), 2014

Bone marrow adipose tissue (BMAT) is different from fat found elsewhere in the body, and only rec... more Bone marrow adipose tissue (BMAT) is different from fat found elsewhere in the body, and only recently have some of its functions been investigated. BMAT may regulate bone marrow stem cell niche and plays a role in energy storage and thermogenesis. BMAT may be involved also in obesity and osteoporosis onset. Given the paramount functions of BMAT, we decided to better clarify the human bone marrow adipogenesis by analyzing the role of the retinoblastoma gene family, which are key players in cell cycle regulation. Our data provide evidence that the inactivation of RB1 or RB2/P130 in uncommitted bone marrow stromal cells (BMSC) facilitates the first steps of adipogenesis. In cultures with silenced RB1 or RB2/P130, we observed an increase of clones with adipogenic potential and a higher percentage of cells accumulating lipid droplets. Nevertheless, the absence of RB1 or RB2/P130 impaired the terminal adipocyte differentiation and gave rise to dysregulated adipose cells, with alteration ...

Research paper thumbnail of Unusual Stüve-Wiedemann syndrome with complete maternal chromosome 5 isodisomy

Annals of clinical and translational neurology, 2014

A woman was isozygous for a novel mutation in the leukemia inhibitory factor receptor gene (LIFR)... more A woman was isozygous for a novel mutation in the leukemia inhibitory factor receptor gene (LIFR) (c.2170C>G; p.Pro724Ala) which disrupts LIFR downstream signaling and results in Stüve-Wiedemann syndrome (STWS). She inherited two identical chromosomes 5 from her mother, heterozygous for the LIFR mutation. The presentation was typical for STWS, except there was no long bone dysplasia. Prominent cold-induced sweating and heat intolerance lead to an initial diagnosis of cold-induced sweating syndrome, excluded by exome sequencing. Skin biopsies provide the first human evidence of failed postnatal cholinergic differentiation of sympathetic neurons innervating sweat glands in cold-induced sweating, and of a neuropathy.

Research paper thumbnail of RB2/p130 ectopic gene expression in neuroblastoma stem cells: evidence of cell-fate restriction and induction of differentiation

Biochemical Journal - BIOCHEM J, 2001

The activity of the RB2/p130 gene, which is a member of the retinoblastoma gene family, is cell-c... more The activity of the RB2/p130 gene, which is a member of the retinoblastoma gene family, is cell-cycle-regulated and plays a key role in growth inhibition and differentiation. We used neuroblastoma cell lines as a model for studies on neural crest progenitor cell differentiation. We show that Rb2/p130 ectopic protein expression induces morphological and molecular modifications, promoting differentiation of intermediate (I) phenotype SK-N-BE(2)-C neuroblastoma cells towards a neuroblastic (N) rather than a Schwann/glial/melanocytic (S) phenotype. These modifications are stable as they persist even after treatment with an S-phenotype inducer. Rb2/p130 ectopic expression also induces a more differentiated phenotype in N-type SH-SY-5Y cells. Further, this function appears to be independent of cell-cycle withdrawal. The data reported suggest that the Rb2/p130 protein is able to induce neuronal lineage specification and differentiation in neural crest stem and committed neuroblastoma cells, respectively. Thus, the Rb2/p130 protein seems to be required throughout the full neural maturation process.

Research paper thumbnail of Modulation of cytokine production in activated human monocytes by somatostatin

Neuropeptides, 1996

The immunosuppressor effects of the widely distributed neuropeptide somatostatin were examined on... more The immunosuppressor effects of the widely distributed neuropeptide somatostatin were examined on purified peripheral blood human monocytes. Somatostatin, at concentrations thought to be physiologic (10−10−10−7 M), regulated monocyte/macrophage responses to (LPS) stimulation, as reflected by interleukin production. In particular, somatostatin had direct inhibitory effects on TNF-α, IL-1β, and IL-6 secretion by LPS-activated monocytes, while the decrease on IL-8 synthesis was

Research paper thumbnail of MRI "fogging" in cerebellar ischaemia: case report

Neuroradiology, 1997

Subacute cerebral infarcts may appear normal on T2-weighted MRI as an area isointense with surrou... more Subacute cerebral infarcts may appear normal on T2-weighted MRI as an area isointense with surrounding normal tissue. This MRI "fogging effect" has been described in only a few cases. We present a further case of fogging observed during the evolution of a cerebellar infarct.

Research paper thumbnail of Giant thrombosed intracavernous carotid artery aneurysm presenting as Tolosa–Hunt syndrome in a patient harboring a new pathogenic neurofibromatosis type 1 mutation: a case report and review of the literature

Neuropsychiatric Disease and Treatment, 2014

Research paper thumbnail of The ADAMTS18 gene is responsible for autosomal recessive early onset severe retinal dystrophy

Orphanet Journal of Rare Diseases, 2013

Background: Inherited retinal dystrophies, including Retinitis Pigmentosa and Leber Congenital Am... more Background: Inherited retinal dystrophies, including Retinitis Pigmentosa and Leber Congenital Amaurosis among others, are a group of genetically heterogeneous disorders that lead to variable degrees of visual deficits. They can be caused by mutations in over 100 genes and there is evidence for the presence of as yet unidentified genes in a significant proportion of patients. We aimed at identifying a novel gene for an autosomal recessive form of early onset severe retinal dystrophy in a patient carrying no previously described mutations in known genes.

Research paper thumbnail of Alessio et al. 2018 Muse OT_044397_preprint.pdf

Research paper thumbnail of Phosphodiesterase 10A (PDE10A) localization in the R6/2 mouse model of Huntington's disease

Neurobiology of Disease, 2013

Research paper thumbnail of Autosomal dominant hereditary spastic paraplegia: report of a large italian family with R581X spastin mutation

Neurological Sciences, 2007

ABSTRACT We describe a large kindred with a typical pure form of autosomal dominant hereditary sp... more ABSTRACT We describe a large kindred with a typical pure form of autosomal dominant hereditary spastic paraplegia (ADHSP). On the basis of maximum LOD score of 1.94 at theta (max)=0 with marker D2S367, we obtained suggestive evidence for linkage of ADHSP to SPG4 locus. Denaturing high-performance liquid chromatography (DHPLC) and direct sequence analysis allowed us to identify a nonsense mutation (1741* C>T) in exon 17 of the Spastin gene. This transition, carried by all the affected family members and two apparently healthy individuals, lead to truncation of the last 36 amino acids in the C-terminus of the protein. These results confirm the existence of mutation in the SPG4 gene with a reduced penetrance, indicating that other genetic or environmental factors are required to trigger full-blown disease.

Research paper thumbnail of Changes in the expression of extracellular regulated kinase (ERK 1/2) in the R6/2 mouse model of Huntington's disease after phosphodiesterase IV inhibition

Neurobiology of Disease, 2012

immunohistochemistry ERK rolipram Huntington's disease R6/2 The mitogen-activated protein kinases... more immunohistochemistry ERK rolipram Huntington's disease R6/2 The mitogen-activated protein kinases (MAPKs) superfamily comprises three major signaling pathways: the extracellular signal-regulated protein kinases (ERKs), the c-Jun N-terminal kinases or stress-activated protein kinases (JNKs/SAPKs) and the p38 family of kinases. ERK 1/2 signaling has been implicated in a number of neurodegenerative disorders, including Huntington's disease (HD). Phosphorylation patterns of ERK 1/2 and JNK are altered in cell models of HD. In this study, we aimed at studying the correlations between ERK 1/2 and the neuronal vulnerability to HD degeneration in the R6/2 transgenic mouse model of HD. Single and double-label immunofluorescence for phospho-ERK (pERK, the activated form of ERK) and for each of the striatal neuronal markers were employed on perfusion-fixed brain sections from R6/2 and wild-type mice. Moreover, Phosphodiesterase 4 inhibition through rolipram was used to study the effects on pERK expression in the different types of striatal neurons. We completed our study with western blot analysis. Our study shows that pERK levels increase with age in the medium spiny striatal neurons and in the parvalbumin interneurons, and that rolipram counteracts such increase in pERK. Conversely, cholinergic and somatostatinergic interneurons of the striatum contain higher levels of pERK in the R6/2 mice compared to the controls. Rolipram induces an increase in pERK expression in these interneurons. Thus, our study confirms and extends the concept that the expression of phosphorylated ERK 1/2 is related to neuronal vulnerability and is implicated in the pathophysiology of cell death in HD.

Research paper thumbnail of Myotonic Dystrophy: Antisense Oligonucleotide Inhibition of DMPK Gene Expression in Vitro

Biochemical and Biophysical Research Communications, 1996

Antisense phosphorothioate oligonucleotides, targeted against the first codon starting region of ... more Antisense phosphorothioate oligonucleotides, targeted against the first codon starting region of DMPK mRNA, were successfully used in K562 and HepG2 cells to decrease DMPK expression. The most effective antisense oligo, MIO1, when added to K562 cells, shows a 75% reduction of the DMPK gene expression 6 hours after addition. The same molecule, when encapsulated in liposomes, delays myotonin mRNA decrease

Research paper thumbnail of MRI "fogging" in cerebellar ischaemia: case report

Neuroradiology, 1997

Subacute cerebral infarcts may appear normal on T2-weighted MRI as an area isointense with surrou... more Subacute cerebral infarcts may appear normal on T2-weighted MRI as an area isointense with surrounding normal tissue. This MRI "fogging effect" has been described in only a few cases. We present a further case of fogging observed during the evolution of a cerebellar infarct.

Research paper thumbnail of Modulation of cytokine production in activated human monocytes by somatostatin

Neuropeptides, 1996

The immunosuppressor effects of the widely distributed neuropeptide somatostatin were examined on... more The immunosuppressor effects of the widely distributed neuropeptide somatostatin were examined on purified peripheral blood human monocytes. Somatostatin, at concentrations thought to be physiologic (10−10−10−7 M), regulated monocyte/macrophage responses to (LPS) stimulation, as reflected by interleukin production. In particular, somatostatin had direct inhibitory effects on TNF-α, IL-1β, and IL-6 secretion by LPS-activated monocytes, while the decrease on IL-8 synthesis was

Research paper thumbnail of Revelation of a New Mitochondrial DNA Mutation (G12147A) in a MELAS/MERFF Phenotype

Archives of Neurology, 2004

A 26-year-old man presented at onset with the syndrome of mitochondrial encephalomyopathy, lactic... more A 26-year-old man presented at onset with the syndrome of mitochondrial encephalomyopathy, lactic acidosis, and strokelike episodes (MELAS) and later with a phenotype for MELAS and myoclonic epilepsy and ragged red fiber disease (MELAS/MERRF). To identify the possible defects in the mitochondrial genome in blood and muscle samples of the patient. Case study of a patient clinically exhibiting strokelike episodes and then epilepsy with myoclonic features, ataxia, and dementia. Research unit of a university hospital. Electromyographic, morphologic, and biochemical studies of muscle and molecular analysis of blood and muscle to investigate mitochondrial DNA (mtDNA) size and quantity. Morphologically, we found abnormal mitochondrial proliferation with several cytochrome-c oxidase (COX)-negative fibers in muscle biopsy specimens; the analysis of serial sections showed a decreased immunoreactivity for the mtDNA-encoded subunits COXII and, partially, COXI. Biochemically, we found a partial and isolated COX deficiency. The complete mtDNA sequence analysis identified 3 sequence changes, 2 of which were reported polymorphisms. The remaining change, a G12147A transition in the transfer RNA(His) gene, appeared to be the likely pathogenic mutation. Our data propose that the G12147A change, the first mutation in the transfer RNA(His) gene associated with an overlapped MELAS/MERFF phenotype, is the cause of the encephalomyopathy in this patient interfering with the overall mitochondrial protein synthesis.

Research paper thumbnail of Abnormal accumulation of tTGase products in muscle and erythrocytes of chorea-acanthocytosis patients

Journal of neuropathology and experimental neurology, 2002

Chorea-Acanthocytosis (CHAC) is an autosomal recessive disease characterized by neurodegeneration... more Chorea-Acanthocytosis (CHAC) is an autosomal recessive disease characterized by neurodegeneration and acanthocytosis. Enhanced creatine kinase concentration is a constant feature of the condition. The mechanism underlying CHAC is unknown. However, acanthocytosis and enhanced creatine kinase suggest a protein defect that deranges the membrane-cytoskeleton interface in erythrocytes and muscle, thereby resulting in neurodegeneration. Acanthocytes have been correlated with structural and functional changes in membrane protein band 3--a ubiquitous anion transporter. Residue Gln-30 of band 3 serves as a membrane substrate for tissue transglutaminase (tTGase), which belongs to a class of intra- and extra-cellular Ca2+-dependent cross-linking enzymes found in most vertebrate tissues. In an attempt to cast light on the pathophysiology of CHAC, we used reverse-phase HPLC and immunohistochemistry to evaluate the role of tTGase in this disorder. We found increased amounts of tTGase-derived N(ep...

Research paper thumbnail of pRb2/p130 gene overexpression induces astrocyte differentiation

Molecular and cellular neurosciences, 2001

There are many data on the activity of the RB gene in neural differentiation and apoptosis, but t... more There are many data on the activity of the RB gene in neural differentiation and apoptosis, but the role of pRb2/p130 in neuronal and glial maturation has been far less investigated. To elucidate the role of pRb2/p130 in astrocyte development we overexpressed this protein in astrocytoma and normal astrocyte cultures by adenoviral-mediated gene transfer. In astrocytoma cells, p130/RB2 overexpression resulted in a significant reduction of cell growth and in an increased G(0)/G(1) cell population. We did not observe any induction of programmed cell death as determined by TUNEL reaction. Interestingly, pRb2/p130 overexpression induced astrocyte differentiation. Astrocyte cell cycle arrest and differentiation seemed to proceed through a way distinct from the p53 pathway.

Research paper thumbnail of Ruta graveolens L. Induces Death of Glioblastoma Cells and Neural Progenitors, but Not of Neurons, via ERK 1/2 and AKT Activation

PLOS ONE, 2015

Glioblastoma multiforme is a highly aggressive brain tumor whose prognosis is very poor. Due to e... more Glioblastoma multiforme is a highly aggressive brain tumor whose prognosis is very poor. Due to early invasion of brain parenchyma, its complete surgical removal is nearly impossible, and even after aggressive combined treatment (association of surgery and chemo- and radio-therapy) five-year survival is only about 10%. Natural products are sources of novel compounds endowed with therapeutic properties in many human diseases, including cancer. Here, we report that the water extract of Ruta graveolens L., commonly known as rue, induces death in different glioblastoma cell lines (U87MG, C6 and U138) widely used to test novel drugs in preclinical studies. Ruta graveolens' effect was mediated by ERK1/2 and AKT activation, and the inhibition of these pathways, via PD98058 and wortmannin, reverted its antiproliferative activity. Rue extract also affects survival of neural precursor cells (A1) obtained from embryonic mouse CNS. As in the case of glioma cells, rue stimulates the activation of ERK1/2 and AKT in A1 cells, whereas their blockade by pharmacological inhibitors prevents cell death. Interestingly, upon induction of differentiation and cell cycle exit, A1 cells become resistant to rue's noxious effects but not to those of temozolomide and cisplatin, two alkylating agents widely used in glioblastoma therapy. Finally, rutin, a major component of the Ruta graveolens water extract, failed to cause cell death, suggesting that rutin by itself is not responsible for the observed effects. In conclusion, we report that rue extracts induce glioma cell death, discriminating between proliferating/undifferentiated and non-proliferating/differentiated neurons. Thus, it can be a promising tool to isolate novel drugs and also to discover targets for therapeutic intervention.

Research paper thumbnail of High grade glioblastoma is associated with aberrant expression of ZFP57, a protein involved in gene imprinting, and of CPT1A and CPT1C that regulate fatty acid metabolism

Cancer Biology & Therapy, 2014

The diagnosis of glioblastoma is still based on tumor histology, but emerging molecular diagnosis... more The diagnosis of glioblastoma is still based on tumor histology, but emerging molecular diagnosis is becoming an important part of glioblastoma classification. Besides the well-known cell cycle-related circuitries that are associated with glioblastoma onset and development, new insights may be derived by looking at pathways involved in regulation of epigenetic phenomena and cellular metabolism, which may both be highly deregulated in cancer cells. We evaluated if in glioblastoma patients the high grade of malignancy could be associated with aberrant expression of some genes involved in regulation of epigenetic phenomena and lipid metabolism. We measured the mRNA levels of ZFP57, TRIM28, CPT1A, CPT1B, and CPT1C in a cohort of 80 patients divided in two groups: grade II and grade IV. We evidenced that high grade glioblastoma is associated with increased level of ZFP57, a protein involved in gene imprinting, and aberrant expression of CPT1A and CPT1C, regulators of fatty acid oxidation. Our study may pave the way to identify new markers that could be potentially useful for diagnosis and/or prognosis of glioblastoma.

Research paper thumbnail of Genes involved in regulation of stem cell properties: studies on their expression in a small cohort of neuroblastoma patients

Cancer biology & therapy, 2009

Cancer stem cells have been isolated from many tumors. Several evidences prove that neuroblastoma... more Cancer stem cells have been isolated from many tumors. Several evidences prove that neuroblastoma contains its own stem cell-like cancer cells. We chose to analyze 20 neuroblastoma tumor samples in the expression of 13 genes involved in the regulation of stem cell properties to evaluate if their misregulation could have a clinical relevance. In several specimens we detected the expression of genes belonging to the OCT3/SOX2/NANOG/KLF4 core circuitry that acts at the highest level in regulating stem cell biology. This result is in agreement with studies showing the existence of malignant stem cells in neuroblastoma. We also observed differences in the expression of some stemness-related genes that may be useful for developing new prognostic analyses. In fact, preliminary data suggests that the presence/absence of UTF1 along with differences in BMI1 mRNA levels could distinguish low grade neuroblastomas from IV stage tumors.

Research paper thumbnail of Silencing of RB1 and RB2/P130 during adipogenesis of bone marrow stromal cells results in dysregulated differentiation

Cell cycle (Georgetown, Tex.), 2014

Bone marrow adipose tissue (BMAT) is different from fat found elsewhere in the body, and only rec... more Bone marrow adipose tissue (BMAT) is different from fat found elsewhere in the body, and only recently have some of its functions been investigated. BMAT may regulate bone marrow stem cell niche and plays a role in energy storage and thermogenesis. BMAT may be involved also in obesity and osteoporosis onset. Given the paramount functions of BMAT, we decided to better clarify the human bone marrow adipogenesis by analyzing the role of the retinoblastoma gene family, which are key players in cell cycle regulation. Our data provide evidence that the inactivation of RB1 or RB2/P130 in uncommitted bone marrow stromal cells (BMSC) facilitates the first steps of adipogenesis. In cultures with silenced RB1 or RB2/P130, we observed an increase of clones with adipogenic potential and a higher percentage of cells accumulating lipid droplets. Nevertheless, the absence of RB1 or RB2/P130 impaired the terminal adipocyte differentiation and gave rise to dysregulated adipose cells, with alteration ...

Research paper thumbnail of Unusual Stüve-Wiedemann syndrome with complete maternal chromosome 5 isodisomy

Annals of clinical and translational neurology, 2014

A woman was isozygous for a novel mutation in the leukemia inhibitory factor receptor gene (LIFR)... more A woman was isozygous for a novel mutation in the leukemia inhibitory factor receptor gene (LIFR) (c.2170C>G; p.Pro724Ala) which disrupts LIFR downstream signaling and results in Stüve-Wiedemann syndrome (STWS). She inherited two identical chromosomes 5 from her mother, heterozygous for the LIFR mutation. The presentation was typical for STWS, except there was no long bone dysplasia. Prominent cold-induced sweating and heat intolerance lead to an initial diagnosis of cold-induced sweating syndrome, excluded by exome sequencing. Skin biopsies provide the first human evidence of failed postnatal cholinergic differentiation of sympathetic neurons innervating sweat glands in cold-induced sweating, and of a neuropathy.

Research paper thumbnail of RB2/p130 ectopic gene expression in neuroblastoma stem cells: evidence of cell-fate restriction and induction of differentiation

Biochemical Journal - BIOCHEM J, 2001

The activity of the RB2/p130 gene, which is a member of the retinoblastoma gene family, is cell-c... more The activity of the RB2/p130 gene, which is a member of the retinoblastoma gene family, is cell-cycle-regulated and plays a key role in growth inhibition and differentiation. We used neuroblastoma cell lines as a model for studies on neural crest progenitor cell differentiation. We show that Rb2/p130 ectopic protein expression induces morphological and molecular modifications, promoting differentiation of intermediate (I) phenotype SK-N-BE(2)-C neuroblastoma cells towards a neuroblastic (N) rather than a Schwann/glial/melanocytic (S) phenotype. These modifications are stable as they persist even after treatment with an S-phenotype inducer. Rb2/p130 ectopic expression also induces a more differentiated phenotype in N-type SH-SY-5Y cells. Further, this function appears to be independent of cell-cycle withdrawal. The data reported suggest that the Rb2/p130 protein is able to induce neuronal lineage specification and differentiation in neural crest stem and committed neuroblastoma cells, respectively. Thus, the Rb2/p130 protein seems to be required throughout the full neural maturation process.

Research paper thumbnail of Modulation of cytokine production in activated human monocytes by somatostatin

Neuropeptides, 1996

The immunosuppressor effects of the widely distributed neuropeptide somatostatin were examined on... more The immunosuppressor effects of the widely distributed neuropeptide somatostatin were examined on purified peripheral blood human monocytes. Somatostatin, at concentrations thought to be physiologic (10−10−10−7 M), regulated monocyte/macrophage responses to (LPS) stimulation, as reflected by interleukin production. In particular, somatostatin had direct inhibitory effects on TNF-α, IL-1β, and IL-6 secretion by LPS-activated monocytes, while the decrease on IL-8 synthesis was

Research paper thumbnail of MRI "fogging" in cerebellar ischaemia: case report

Neuroradiology, 1997

Subacute cerebral infarcts may appear normal on T2-weighted MRI as an area isointense with surrou... more Subacute cerebral infarcts may appear normal on T2-weighted MRI as an area isointense with surrounding normal tissue. This MRI "fogging effect" has been described in only a few cases. We present a further case of fogging observed during the evolution of a cerebellar infarct.

Research paper thumbnail of Giant thrombosed intracavernous carotid artery aneurysm presenting as Tolosa–Hunt syndrome in a patient harboring a new pathogenic neurofibromatosis type 1 mutation: a case report and review of the literature

Neuropsychiatric Disease and Treatment, 2014