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Phosphoinositide-specific phospholipases C (PLCs) are a class of enzymes involved in several cell activities, such as cell cycle regulation, proliferation, differentiation and cytoskeletal dynamics. Among these enzymes, PLCγ1 is one of the most expressed PLCs in the brain, contributing to a complex network in the developing nervous system. Several studies have shown that PLCγ1 signaling imbalance is linked to several brain disorders, including glioblastoma, the most aggressive brain tumor in adults. Indeed, it has been demonstrated a link between PLCγ1 inhibition and the arrest of glioma cell motility of fetal rat brain aggregates and the impairment of cell invasion abilities following its down-regulation. This study aims to determine the pathological influence of PLCγ1 in glioblastoma, through a translational study which combines in silico data, data from glioblastoma patients' samples and data on engineered cell lines. We found out that PLCγ1 gene expression correlates with the pathological grade of gliomas, and it is higher in fifty patients' glioblastoma tissue samples compared to twenty healthy controls. Moreover, it was demonstrated that PLCγ1 silencing in U87-MG leads to a reduction in cell migration and invasion abilities. The opposite trend was observed following PLCγ1 overexpression, suggesting an interesting possible involvement of PLCγ1 in gliomas' aggressiveness.

The immune system is a complex network that acts to protect vertebrates from foreign microorganisms and carries out immunosurveillance to combat cancer. In order to avoid hyper-activation of the immune system leading to collateral damage tissues and organs and to prevent self-attack, the network has the intrinsic control mechanisms that negatively regulate immune responses. Central to this negative regulation are regulatory T (T-Reg) cells, which through cytokine secretion and cell interaction limit uncontrolled clonal expansion and functions of activated immune cells. Given that positive or negative manipulation of T-Regs activity could be utilised to therapeutically treat host versus graft rejection or cancer respectively, understanding how signaling pathways impact on T-Regs function should reveal potential targets with which to intervene. The phosphatidylinositol-3-kinase (PI3K) pathway controls a vast array of cellular processes and is critical in T cell activation. Here we focus on phosphoinositide 3-kinases (PI3Ks) and their ability to regulate T-Regs cell differentiation and function.

This study investigated the fate of the stent inner surface in carotid artery stenting (CAS). In addition, the occurrence of late cerebral micro-embolism after CAS has been studied in order to identify predictors and correlate it with a possible neo-intimal layer. METHODS: A series of patients were evaluated before CAS through aortic arch trans-oesophageal echocardiography. Six months after CAS, the stent coverage by neo-intima and the possible presence of uncovered plaques were determined by high-resolution duplex scanning (5-17-Hz probe and 3D reconstruction). Possible micro-embolic signals (MESs) were evaluated through transcranial duplex scanning (30-min analysis of ipsilateral middle cerebral artery with a 1-4-Hz probe) and correlated with patients' characteristics, intimal media thickness (IMT) (>0.9mm vs. 4mm). Fisher's and Wilcoxon tests were used to evaluate differences across groups for categorical and continuous variables, respectively. RESULTS: In the 68 CASs examined (40 closed cells and 28 open cells), the stent was completely covered by neo-intima in 52 cases (76.4%). Complete coverage was significantly correlated with IMT

Carotid artery stenting (CAS) leads to frequent embolic brain lesions; their source has not been clearly identified yet. In order to investigate this phenomenon, we have evaluated embolic brain lesions (BL) after CAS and correlated them with aortic arch (AA) characteristics.The AAs of 59 patients undergoing CAS under distal protection were evaluated by angiography and transesophageal echocardiography (TEE). AAs were stratified according to morphology (type I and II "simple" vs type III and bovine "difficult"), atherosclerotic arch lesions (complicated: >5 mm or with mobile debris vs uncomplicated: 150). Diffusion weighted imaging (DWI) was performed before and within 24 hours from CAS. New BL were considered ipsilateral (IL) if ipsilateral to the site of CAS and non-ipsilateral (CL) if contralateral to it or bilateral. Normality distribution was by Shapiro-Wilk test (variables reported as medians +/- interquartile range) and statistical significance (P < .05) by Wilcoxon and Fisher's exact test.Difficult arches were present in 17 patients (28.8\%), complicated aortic plaque in 21 (35.5\%), and TI > 150 in 34 (57.6\%). New BL appeared in 34 or 57.6\% patients (6 or 18\% IL and 28 or 82\% CL). The mean number of BL was 5.7 (range, 0 to 20), 4.7 IL, and 5.7 CL, with a median volume of 560.95 +/- 1677.7 mm(3). Type of arch and TI were not correlated with mean number of BL. Mean volume of BL were greater in patients with difficult AA, complicated plaques, and TI > 150 (258 (572) mm(3) vs 15.6 (353) mm(3), P = .2; and 86 (828) mm(3) vs 85.9 (352) mm(3), P = .4 172 (766) mm(3) vs 0 (228) mm(3), P = .06, respectively). In patients with all three AA characteristics, mean number and volume of BL was significantly greater compared with other patients. Specifically, this increase was due mainly to CL (IL 0 (117) mm(3) vs 0 (172) mm(3), P = .9; CL 564 (687) mm(3) vs 0 (133) mm(3), P = .001). None of the technical details considered was correlated with either IL or CL.BL are frequent after protected CAS and are correlated with AA characteristics, thus underlining the role of catheterization maneuvers in determining embolic events. TEE may be useful in patient's selection for CAS

A large number of observations have hinted at the fact that location impinges on function of some of the main players of nuclear inositol lipid cycle. PLC beta1 is a well-known example, given that it has been shown that only the enzyme located in the nucleus targets the cyclin D3/cdk4 complex, playing, in turn, a key role in the control of normal progression through the G1 phase of the cell cycle. The PLC beta1 gene, which is constituted of 36 small exons and large introns, maps on the short arm of human chromosome 20 (20pl2, nearby markers D20S917 and D20S177) with the specific probe (PAC clone HS881E24) spanning from exon 19 to 32 of the gene itself. The chromosome band 20pl2 has been shown to be rearranged in human diseases such as solid tumors without a more accurate definition of the alteration, maybe because of the absence of candidate genes or specific probes. Moreover, non-specific alterations in chromosome 20 have been found in patients affected by MDS and acute myeloid leukemia AML. MDS is an adult hematological disease that evolves into AML in about 30% of the cases. The availability of a highly specific probe gave an opportunity to perform in patients affected with MDS/AML, associated with normal karyotype, painting and FISH analysis aimed to check the PLC beta1 gene, given that this signaling molecule is a key player in the control of some checkpoints of the normal progression through the cell cycle. FISH analysis disclosed in a small group of MDS/AML patients with normal karyotype the monoallelic deletion of the PLC beta1 gene. In contrast, PLC beta4, another gene coding for a signaling molecule, located on 20pl2.3 at a distance as far as less than 1 Mb from PLC beta1, is unaffected in MDS patients with the deletion of PLC beta1 gene, hinting at an interstitial deletion. The MDS patients, bearing the deletion, rapidly evolved to AML, whilst the normal karyotype MDS patients, showing non-deletion of PLC beta1 gene, are still alive at least 24 months after the diagnosis. The immunocytochemical analysis using an anti PLC beta1 monoclonal antibody showed that all the AML/MDS patients who were normal at FISH analysis also had normal staining of the nucleus, which is a preferential site for PLC beta1. In contrast, the monoallelic deletion gave rise to a dramatic decrease of the nuclear staining suggesting a decreased expression of the nuclear PLC beta1. The reported data strengthen the contention of a key role played by PLC beta1 in the nucleus, suggest a possible involvement of PLC beta1 in the progression of MDS to AML and pave the way for a larger investigation aimed at identifying a possible high risk group among MDS patients with a normal karyotype.

Previous evidence from independent laboratories has shown that the nucleus contains diacylglycerol kinase (DGK) isoforms, i.e., the enzymes, which yield phosphatidic acid from diacylglycerol, thus terminating protein kinase C-mediated signaling events. A DGK isoform, which resides in the nucleus of PC12 cells, is DGK-theta. Here, we show that nerve growth factor (NGF) treatment of serum-starved PC12 cells results in the stimulation of both a cytoplasmic and a nuclear DGK activity. However, time course analysis shows that cytoplasmic DGK activity peaked earlier than its nuclear counterpart. While nuclear DGK activity was dramatically down-regulated by a monoclonal antibody known for selectively inhibiting DGK-theta, cytoplasmic DGK activity was not. Moreover, nuclear DGK activity was stimulated by phosphatidylserine, an anionic phospholipid that had no effect on cytoplasmic DGK activity. Upon NGF stimulation, the amount and the activity of DGK-theta, which was bound to the insoluble nuclear matrix fraction, substantially increased. Epidermal growth factor up-regulated a nuclear DGK activity insensitive to anti-DGK-theta monoclonal antibody. Overall, our findings identify nuclear DGK-theta as a down-stream target of NGF signaling in PC12 cells.

To establish the risk of carotid artery stent (CAS) complications in patients with aortic arch anomalies.In a prospective series of patients submitted to CAS, all cases with arch anomalies were compared with cases with normal arch anatomy (type I, II and III) in order to assess the impact of anatomic characteristics on technical and clinical outcome. Outcome was evaluated in term of neurological complications and technical success.Of 214 consecutive patients undergoing CAS, 189 (88.3\%) had normal arch anatomy and 25 (11.7\%) arch anomalies. The arch abnormalities included common origin of brachiocephalic trunk and left common carotid artery in 22 cases (10.2\%), separate origin of right subclavian and common carotid in 2 cases (0.9\%) and left common carotid agenesis with separate arch origin of internal and external carotid in 1 case (0.5\%). The two groups were not different in term of epidemiology and preoperative clinical and morphological characteristics. Technical failure occurred overall in 26 cases (12\%) and neurological complication in 14 cases (6.5\%). All symptoms were temporary. Technical failure was higher in the arch anomaly group; however the difference did not reach statistical significance (89.6\% vs 76.4\%, P=0.1). Neurological complications occurred more frequently in the arch anomaly group (20\% vs 5.3\%, P=0.039). Type of arch was the only variable independently associated with neurological complications (OR=2.01, p=0.026).Aortic arch anomalies are not infrequent and are associated with increased risk of neurological complications. The indication for CAS should be carefully evaluated in these cases OBJECTIVE: To establish the risk of carotid artery stent (CAS) complications in patients with aortic arch anomalies. METHODS: In a prospective series of patients submitted to CAS, all cases with arch anomalies were compared with cases with normal arch anatomy (type I, II and III) in order to assess the impact of anatomic characteristics on technical and clinical outcome. Outcome was evaluated in term of neurological complications and technical success. RESULTS: Of 214 consecutive patients undergoing CAS, 189 (88.3%) had normal arch anatomy and 25 (11.7%) arch anomalies. The arch abnormalities included common origin of brachiocephalic trunk and left common carotid artery in 22 cases (10.2%), separate origin of right subclavian and common carotid in 2 cases (0.9%) and left common carotid agenesis with separate arch origin of internal and external carotid in 1 case (0.5%). The two groups were not different in term of epidemiology and preoperative clinical and morphological characteristics. Technical failure occurred overall in 26 cases (12%) and neurological complication in 14 cases (6.5%). All symptoms were temporary. Technical failure was higher in the arch anomaly group; however the difference did not reach statistical significance (89.6% vs 76.4%, P=0.1). Neurological complications occurred more frequently in the arch anomaly group (20% vs 5.3%, P=0.039). Type of arch was the only variable independently associated with neurological complications (OR=2.01, p=0.026). CONCLUSION: Aortic arch anomalies are not infrequent and are associated with increased risk of neurological complications. The indication for CAS should be carefully evaluated in these cases.