Nuclear PARP-1 protein overexpression is associated with poor overall survival in early breast cancer

BACKGROUND

Poly(ADP-ribose)polymerase-1 (PARP-1) is a highly promising novel target in breast cancer. However, the expression of PARP-1 protein in breast cancer and its associations with outcome are yet poorly characterized.

PATIENTS AND METHODS

Quantitative expression of PARP-1 protein was assayed by a specific immunohistochemical signal intensity scanning assay in a range of normal to malignant breast lesions, including a series of patients (N = 330) with operable breast cancer to correlate with clinicopathological factors and long-term outcome.

RESULTS

PARP-1 was overexpressed in about a third of ductal carcinoma in situ and infiltrating breast carcinomas. PARP-1 protein overexpression was associated to higher tumor grade (P = 0.01), estrogen-negative tumors (P < 0.001) and triple-negative phenotype (P < 0.001). The hazard ratio (HR) for death in patients with PARP-1 overexpressing tumors was 7.24 (95% CI; 3.56-14.75). In a multivariate analysis, PARP-1 overexpression was an independent prognostic factor for both disease-free (HR 10.05; 95% CI 5.42-10.66) and overall survival (HR 1.82; 95% CI 1.32-2.52).

CONCLUSIONS

Nuclear PARP-1 is overexpressed during the malignant transformation of the breast, particularly in triple-negative tumors, and independently predicts poor prognosis in operable invasive breast cancer.

Plasma β-amyloid levels in cerebral amyloid angiopathy-associated hemorrhagic stroke

BACKGROUND

Cerebral amyloid angiopathy (CAA) is one of the main causes of intracerebral hemorrhage (ICH) in the elderly.

OBJECTIVE

To analyze β-amyloid (Aβ) species in plasma in order to uncover biological markers that may contribute to improve the diagnosis of CAA in life.

METHODS

We determined the level of Aβ(1-40), Aβ(N-40), Aβ(1-42) and Aβ(N-42) in plasma of CAA-related ICH patients (n = 29) and healthy controls (n = 21) using xMAP® technology. Hemorrhages were identified and classified using a CT scan and brain MRI. Patients were clinically classified as probable or possible CAA according to the Boston criteria.

RESULTS

We found that plasma full-length Aβ(1-42) and truncated fragments Aβ(N-42) were higher in probable CAA patients than in controls (p < 0.001 and p = 0.046, respectively), and full-length Aβ(1-40) was selectively elevated in probable CAA compared to possible cases (p = 0.015) and controls (p = 0.005). In addition, plasma Aβ(N-42) levels were also higher in patients that presented multiple lobar macrohemorrhages compared to patients that had one symptomatic hemorrhagic event (p = 0.022), indicating that a certain degree of CAA severity is necessary to show increased Aβ fragments in peripheral circulation.

CONCLUSION

Our results suggest that specific Aβ fragments in plasma might be considered as potential biomarkers for the diagnosis of CAA.

[Spanish multi-centre observational study of the first attacks suggestive of multiple sclerosis: the PREM cohort]

INTRODUCTION

Recent studies have shown the need to optimise the management of patients after a first attack suggestive of multiple sclerosis (MS). Our aim is to determine whether the results from follow-ups in these studies are reproducible within a Spanish multi-centre context.

PATIENTS AND METHODS

The PREM study (observational prospective Spanish multi-centre study at 24 months) included patients in the first three months following a first event suggestive of MS with at least two typical lesions in a magnetic resonance scan. The Expanded Disability Status Scale (EDSS) was obtained and the presence of attacks was evaluated basally and at 3, 6, 9, 12, 18 and 24 months; a magnetic resonance scan was performed basally and at 6 and 24 months so as to be able to calculate the brain volume and the volumes of the lesions (T1, T2 and T1 after administering gadolinium). McDonald and Poser criteria were evaluated during the follow-up. A subgroup of patients was followed up for a total period of four years.

RESULTS

Altogether 110 patients (67% females) with a mean age of 30.2 years were included in the study; 22 patients dropped out of the study before it finished. Poser criteria were met by 19% and 45% of patients at 6 months and 24 months, respectively; 63% and 71% satisfied McDonald criteria. The EDSS decreased significantly (-0.94; p < 0.001) and development of atrophy was observed (-1.2%; p < 0.001) at 24 months.

CONCLUSIONS

Results of the follow-up of patients with first attacks suggestive of MS within a Spanish multi-centre context are wholly comparable with those from international clinical trials performed in these patients.

MRI assessment of iron deposition in multiple sclerosis

Iron deposition in the human brain tissue occurs in the process of normal aging and in many neurodegenerative diseases. Elevated iron levels in certain brain regions are also an increasingly recognized finding in multiple sclerosis (MS). The exact mechanism(s) for this phenomenon and its implication in terms of pathophysiology and clinical significance are still largely unknown and debated. Reliable methods to exactly quantify brain iron are a first step to clarify these issues. Therefore, the aim of this review is to present currently available magnetic resonance imaging (MRI) techniques for the assessment of brain iron. These include relaxation time mapping, phase imaging, susceptibility-weighted imaging, susceptibility mapping, magnetic field correlation imaging, and direct saturation imaging. After discussing their advantages and disadvantages, existing MRI clinical correlations with brain iron concentration in MS are summarized and future research directions are shown.

MR imaging of neoplastic central nervous system lesions: review and recommendations for current practice

MR imaging is the preferred technique for the diagnosis, treatment planning, and monitoring of patients with neoplastic CNS lesions. Conventional MR imaging, with gadolinium-based contrast enhancement, is increasingly combined with advanced, functional MR imaging techniques to offer morphologic, metabolic, and physiologic information. This article provides updated recommendations to neuroradiologists, neuro-oncologists, neurosurgeons, and radiation oncologists on the practical applications of MR imaging of neoplastic CNS lesions in adults, with particular focus on gliomas, based on a review of the clinical trial evidence and personal experiences shared at a recent international meeting of experts in neuroradiology, neuro-oncology, neurosurgery, and radio-oncology.

MMP-2/MMP-9 plasma level and brain expression in cerebral amyloid angiopathy-associated hemorrhagic stroke

Cerebral amyloid angiopathy (CAA) is one of the main causes of intracerebral hemorrhage (ICH) in the elderly. Matrix metalloproteinases (MMPs) have been implicated in blood-brain barrier disruption and ICH pathogenesis. In this study, we determined the levels MMP-2 and MMP-9 in plasma and their brain expression in CAA-associated hemorrhagic stroke. Although MMP-2 and MMP-9 plasma levels did not differ among patients and controls, their brain expression was increased in perihematoma areas of CAA-related hemorrhagic strokes compared with contralateral areas and nonhemorrhagic brains. In addition, MMP-2 reactivity was found in β-amyloid (Aβ)-damaged vessels located far from the acute ICH and in chronic microbleeds. MMP-2 expression was associated to endothelial cells, histiocytes and reactive astrocytes, whereas MMP-9 expression was restricted to inflammatory cells. In summary, MMP-2 expression within and around Aβ-compromised vessels might contribute to the vasculature fatal fate, triggering an eventual bleeding.

Neuroimaging in acute liver failure

Acute liver failure (ALF) is frequently complicated by the development of brain edema that can lead to intracranial hypertension and severe brain injury. Neuroimaging techniques allow a none-invasive assessment of brain tissue and cerebral hemodynamics by means of transcranial Doppler ultrasonography, magnetic resonance and nuclear imaging with radioligands. These methods have been very helpful to unravel the pathogenesis of this process and have been applied to patients and experimental models. They allow monitoring the outcome of patients with ALF and neurological manifestations. The increase in brain water can be detected by observing changes in brain volume and disturbances in diffusion weighted imaging. Neurometabolic changes are detected by magnetic resonance spectroscopy, which provides a pattern of abnormalities characterized by an increase in glutamine and a decrease in myo-inositol. Disturbances in cerebral blood flow are depicted by SPECT or PET and can be monitored and the bedside by assessing the characteristics of the waveform provided by transcranial Doppler ultrasonography. Neuroimaging methods, which are rapidly evolving, will undoubtedly lead to future diagnostic and therapeutic progress that could be very helpful for patients with ALF.

Neuropsychological profile of bilateral paramedian infarctions: three cases

INTRODUCTION

The thalamus is one of the strategic diencephalic structures of the human brain. The artery of Percheron, an asymmetrical common trunk arising from a P1 segment of the posterior cerebral artery, is a peculiar presentation of the three variants involved in the irrigation of the paramedian thalamic territory. Occlusion of this artery results in bilateral median thalamic infarction. The paramedian syndrome includes an acute loss or reduction of consciousness, often associated with oculomotor and neuropsychological disturbances.

PATIENTS AND METHODS

We present three cases of bilateral paramedian thalamic infarction with onset of acute coma, followed by fluctuations in the level of consciousness, memory, and behavioural alterations. A neuroradiological study with MRI identified individual thalamic nuclei, and a complete neuropsychological study was performed one month after onset of ictus.

RESULTS

One of the patients showed severe memory and executive function impairments without improvement of vertical gaze palsy. The other two patients presented with mild executive dysfunction with complete resolution of neurological symptoms. Neuroimaging results showed a bilateral lesion of the dorsomedial nuclei in the three patients.

CONCLUSIONS

Severe amnesia has been associated with an affection of the structures of the paramedian thalamic territory. Presently, the role of the dorsomedial nucleus remains controversial, with the suggestion that memory deficits observed in this type of lesion could be secondary to executive function deficits. In our case, the patient with the most severe dysexecutive deficit presented the most severe memory impairments.

Biexponential analysis of diffusion-tensor imaging of the brain in patients with cirrhosis before and after liver transplantation

BACKGROUND AND PURPOSE

DTI has shown increased MD of water molecules in the brain of patients with cirrhosis, consistent with low-grade edema. This study further characterizes this edema by using biexponential analysis of DTI data, a technique that may differentiate cytotoxic and vasogenic edema.

MATERIALS AND METHODS

A total of 41 patients with cirrhosis awaiting liver transplantation and 16 healthy controls were studied by DTI by using a single-shot echo-planar technique with 11 b-values (range, 0-7500 s/mm(2)) and 6 noncollinear directions. Measurements were fitted to biexponential function to determine MD and FA for the fast and slow diffusion components. Regions of interest were selected in the parietal white matter and corticospinal tract. The assessment was repeated 1 year after liver transplantation in 24 of these patients.

RESULTS

In parietal white matter, patients with cirrhosis showed an increase in fast MD and a decrease in fast FA that normalized after liver transplantation. In the corticospinal tract, there was an increase in fast and slow MD that normalized after transplantation, and a decrease in FA that persisted posttransplantation. There was no association of DTI parameters with minimal HE (n =12).

CONCLUSIONS

Biexponential analysis of DTI supports the presence of edema in the brain of patients with cirrhosis that reverts after transplantation. In parietal white matter, the increase in brain water was mainly located in the interstitial compartment, while the corticospinal tract showed a mixed pattern (intra- and extracellular). In addition, the findings on posttransplantation were consistent with microstructural damage along the corticospinal tract.

Lipoprotein-associated phospholipase A2 testing usefulness among patients with symptomatic intracranial atherosclerotic disease

BACKGROUND AND PURPOSE

Circulating lipoprotein-associated phospholipase A(2) (Lp-PLA(2)) has emerged as a novel biomarker for cardiovascular diseases. Our aim was to determine Lp-PLA(2) mass and activity in a selected cohort of first-ever transient ischemic attack (TIA) or ischemic stroke patients with intracranial atherosclerotic disease (ICAD) and to investigate its relationship with the presence of classical vascular risk factors, response to secondary prevention treatments and risk of recurrent vascular events.

METHODS

Lp-PLA(2) mass and activity were measured 3 months after TIA or stroke by means of the PLAC test and CAM-assay (diaDexus, Inc.) respectively in 75 patients. Classic vascular risk factors, preventive treatments and clinical characteristics at the time of the index event were recorded. Follow-up transcranial Doppler ultrasonography (TCD) was performed and the presence of a new vascular event was assessed every 6 months.

RESULTS

Several preventive treatments (statins and clopidogrel) were significantly associated with lower Lp-PLA(2) mass and activity. During follow-up (median time 23 months), eighteen patients (24%) suffered a new vascular event. Baseline factors associated with new vascular events were: history of coronary artery disease, number of intracranial stenoses detected by TCD and also Lp-PLA(2) activity, which was the only independent predictor for new vascular events (hazard ratio 2.89; 95% CI 1.029 to 8.096; p=0.044) after multivariate analysis (Cox regression).

CONCLUSIONS

Lp-PLA(2) activity might be a useful tool to identify intracranial large-artery occlusive disease patients at higher risk of suffering new vascular events.

An observational study of the effectiveness and safety of natalizumab in the treatment of multiple sclerosis

AIM

To analyse the safety and effectiveness of natalizumab in the treatment of multiple sclerosis in a real clinical practice setting and according to the approved indications.

PATIENTS AND METHODS

All patients with multiple sclerosis treated with natalizumab in our centre were evaluated. The clinical and radiological disease activity during the first year of treatment was analyzed in patients who received at least 12 doses of the drug. The data regarding moderate and severe adverse events in the entire study sample was also evaluated.

RESULTS

A total of 112 patients were included in the study, of which 110 had been previously treated with other drugs and 76 had received at least 12 doses of natalizumab. In this group, the annualized relapse rate was reduced by 89% compared to the preceding year and 80% of patients were free from relapses after one year of treatment. Nine percent of patients exhibited 3-month confirmed disability progression. At month 12, the mean number of gadolinium-enhancing lesions on brain MRI was decreased by 99% compared to the pre-treatment MRI. During the first year of treatment, 76% of patients remained free from clinical activity and 33% remained free from both clinical and radiological disease activity. Twenty-nine percent of patients had at least one moderate or severe adverse event, which led to treatment discontinuation in 6%. Four percent of patients experienced immediate hypersensitivity reactions.

CONCLUSION

This study suggests that natalizumab is effective in reducing disease activity in patients with relapsing multiple sclerosis and inadequate response to other therapies, with a favorable risk-benefit ratio.

A multicentre study of motor functional connectivity changes in patients with multiple sclerosis

In this multicentre study involving eight European centres, we characterized the spatial pattern of functional connectivity (FC) in the sensorimotor network from 61 right-handed patients with multiple sclerosis (MS) and 74 age-matched healthy subjects assessed with the use of functional magnetic resonance imaging (fMRI) and a simple motor task of their right dominant hand. FC was investigated by using: (i) voxel-wise correlations between the left sensorimotor cortex (SMC) and any other area in the brain; and (ii) bivariate correlations between time series extracted from several regions of interest (ROIs) belonging to the sensorimotor network. Both healthy controls and MS patients had significant FC between the left SMC and several areas of the sensorimotor network, including the bilateral postcentral and precentral gyri, supplementary motor area, middle frontal gyri, insulae, secondary somatosensory cortices, thalami, and right cerebellum. Voxel-wise assessment of FC revealed increased connectivity between the left SMC and the right precentral gyrus, right middle frontal gyrus (MFG) and bilateral postcentral gyri in MS patients as compared with controls. ROI analysis also showed a widespread pattern of altered connectivity, characterized by increased FC between the right MFG, the left insula and the right inferior frontal gyrus in comparison with many regions of the sensorimotor network. These results provide further evidence for increased bihemispheric contributions to motor control in patients with MS relative to healthy controls. They further suggest that multicentre fMRI studies of FC changes are possible, and provide a potential imaging biomarker for use in experimental therapeutic studies directed at enhancing adaptive plasticity in the disease.

Postthrombolysis hemorrhage risk is affected by stroke assessment bias between hemispheres

OBJECTIVE

Stroke symptoms in right hemispheric stroke tend to be underestimated in clinical assessment scales, resulting in greater infarct volumes in right as compared to left hemispheric strokes despite similar clinical stroke severity. We hypothesized that patients with right hemispheric nonlacunar stroke are at higher risk for secondary intracerebral hemorrhage after thrombolysis despite similar stroke severity.

METHODS

We analyzed data of 2 stroke cohorts with CT-based and MRI-based imaging before thrombolysis. Initial stroke severity was measured with the NIH Stroke Scale (NIHSS). Lacunar strokes were excluded through either the presence of cortical symptoms (CT cohort) or restriction to patients with prestroke diffusion-weighted imaging (DWI) lesion size >3.75 mL (MRI cohort). Probabilities of having a parenchymal hematoma were determined using multivariate logistic regression.

RESULTS

A total of 392 patients in the CT cohort and 400 patients in the MRI cohort were evaluated. Although NIHSS scores were similar in strokes of both hemispheres (median NIHSS: CT: 15 vs 13, MRI: 14 vs 16), the frequencies of parenchymal hematoma were higher in right hemispheric compared to left hemispheric strokes (CT: 12.4% vs 5.7%, MRI: 10.4% vs 6.8%). After adjustment for potential confounders (but not pretreatment lesion volume), the probability of parenchymal hematoma was higher in right hemispheric nonlacunar strokes (CT: odds ratio [OR] 2.3; 95% confidence interval [CI] 1.08-4.89; p = 0.032) and showed a borderline significant effect in the MRI cohort (OR 2.1; 95% CI 0.98-4.49; p = 0.057). Adjustment for pretreatment DWI lesion size eliminated hemispheric differences in hemorrhage risk.

CONCLUSIONS

Higher hemorrhage rates in right hemispheric nonlacunar strokes despite similar stroke severity may be caused by clinical underestimation of the proportion of tissue at bleeding risk.

Brainstem lesions in clinically isolated syndromes

BACKGROUND

Number of baseline lesions has been shown to predict future attacks and disability in clinically isolated syndromes (CIS).

OBJECTIVE

To investigate the role of baseline infratentorial lesions in long-term prognosis.

METHODS

Subjects were included in a prospective cohort of patients with CIS. Patients underwent brain MRI within 3 months after CIS onset. Number and location of lesions at baseline were prospectively studied. Retrospective scan analysis was conducted to specifically look at number and location of infratentorial lesions. We analyzed the time to a second attack and to reach EDSS 3.0.

RESULTS

We included 246 patients with CIS followed for a median of 7.7 years. Patients with infratentorial lesions had both a higher risk of conversion (71.4% vs 29.6%; hazard ratio [HR] 3.3; 95% confidence interval [CI] 2.2-4.8; p < 0.001) and of developing disability (32.5% vs 12.4%; HR 2.4; 95% CI 1.3-4.3; p = 0.003). Presence of at least one cerebellar lesion was associated with an increased risk of conversion (HR 2.4; 95% CI 1.3-4.5; p = 0.007). Presence of at least one brainstem lesion increased both the risk of conversion (HR 2.9; 95% CI 1.7-5.0; p < 0.001) and disability (HR 2.5; 95% CI 1.1-5.4; p = 0.026). Broken down into number of lesions, the presence of infratentorial lesions increased both the risk of conversion (83% vs 61%) (HR 22.3; 95% CI 9.7-51.1; p < 0.001) and of reaching EDSS 3.0 (40% vs 19%) (HR 3.2; 95% CI 1.3-7.4; p = 0.008) only in patients with 9 or more lesions.

CONCLUSIONS

Presence of infratentorial lesions increases the risk for disability. Brainstem rather than cerebellar lesions may be responsible for poor prognosis.

Fuzzy approach toward reducing false positives in the detection of small multiple sclerosis lesions in magnetic resonance images

The large number of false positives that result when automatic algorithms are considered for segmenting small multiple sclerosis lesions in magnetic resonance imaging hampers the posterior evaluation of lesion load. To address this problem we propose a fuzzy system which can improve the differentiation between true and false positive detections in proton density- and T2-weighted images. On the basis of an earlier work, which was focused on the detection of hyperintense regions in MR brain images, the system here presented introduces fuzzy restrictions derived from the regional analysis of the main features in such regions. Results show a reduction to a 3.6% in the number of false detections while preserving most of the true detections obtained using previous algorithm.

Hepatic encephalopathy is associated with posttransplant cognitive function and brain volume

Hepatic encephalopathy (HE) is a common complication of cirrhosis that is associated with brain atrophy and may participate in impaired cognitive function after liver transplantation. This study analyzes the relationship of HE with cognitive function and brain volume after transplantation. A total of 52 consecutive patients with cirrhosis (24 alcohol abuse, 24 prior HE, 14 diabetes mellitus) completed a neuropsychological assessment before liver transplantation and again, 6 to 12 months after transplantation. In 24 patients who underwent the posttransplant assessment, magnetic resonance imaging was performed in addition, with measurement of brain volume and relative concentration of N-acetylaspartate (NAA) and creatine/phosphocreatine (Cr), a neuronal marker, by magnetic resonance spectroscopy. Neuropsychological assessment prior to transplantation identified minimal HE in 28 patients. All cognitive indexes improved after liver transplantation, but 7 patients (13%) showed persistent mild cognitive impairment. Global cognitive function after transplantation was poorer in patients with the following variables before liver transplantation: alcohol etiology, diabetes mellitus, and HE. Brain volume after transplantation was smaller in patients with prior HE. Brain volume correlated to NAA/Cr values (r = 0.498, P = 0.013) and poor motor function (r = 0.41, P = 0.049). In conclusion, the association of HE with cognitive function and brain volume suggests that having experienced HE before liver transplantation impairs the posttransplantation neurological outcome.

T2 lesion location really matters: a 10 year follow-up study in primary progressive multiple sclerosis

OBJECTIVES

Prediction of long term clinical outcome in patients with primary progressive multiple sclerosis (PPMS) using imaging has important clinical implications, but remains challenging. We aimed to determine whether spatial location of T2 and T1 brain lesions predicts clinical progression during a 10-year follow-up in PPMS.

METHODS

Lesion probability maps of the T2 and T1 brain lesions were generated using the baseline scans of 80 patients with PPMS who were clinically assessed at baseline and then after 1, 2, 5 and 10 years. For each patient, the time (in years) taken before bilateral support was required to walk (time to event (TTE)) was used as a measure of progression rate. The probability of each voxel being 'lesional' was correlated with TTE, adjusting for age, gender, disease duration, centre and spinal cord cross sectional area, using a multiple linear regression model. To identify the best, independent predictor of progression, a Cox regression model was used.

RESULTS

A significant correlation between a shorter TTE and a higher probability of a voxel being lesional on T2 scans was found in the bilateral corticospinal tract and superior longitudinal fasciculus, and in the right inferior fronto-occipital fasciculus (p<0.05). The best predictor of progression rate was the T2 lesion load measured along the right inferior fronto-occipital fasciculus (p=0.016, hazard ratio 1.00652, 95% CI 1.00121 to 1.01186).

CONCLUSION

Our results suggest that the location of T2 brain lesions in the motor and associative tracts is an important contributor to the progression of disability in PPMS, and is independent of spinal cord involvement.

A functional magnetic resonance proof of concept pilot trial of cognitive rehabilitation in multiple sclerosis

BACKGROUND

Cognitive impairment is frequent in multiple sclerosis (MS) and lacks effective treatment. Cognitive rehabilitation is widely applied in neurorehabilitation settings. Functional magnetic resonance imaging (fMRI) may help in investigating changes in brain activity and provide a tool to assess the efficacy of rehabilitation.

AIM

To investigate the effect on brain activity as measured by fMRI of a cognitive rehabilitation programme in patients with MS and cognitive impairment.

METHOD

Fifteen patients with MS and cognitive impairment and five healthy subjects were recruited. Neuropsychological assessments were performed in patients with MS at study entry and after rehabilitation to assess cognitive changes. fMRI scans were performed at week -5 (baseline), week 0 (immediately before rehabilitation) and week 5 (immediately after rehabilitation). The fMRI paradigm was the Paced Auditory Serial Addition Test (PASAT). The cognitive rehabilitation programme was composed of 15 computer-aided drill and practice sessions and five non-computer-aided cognitive stimulation group sessions (over 5 weeks). Strict guidelines ensured comparability of all rehabilitation interventions.

RESULTS

Patients had increased brain fMRI activity after rehabilitation in several cerebellar areas when compared with healthy subjects. After rehabilitation, patients had significantly improved their performance on the backward version of the Digit Span Test (p = 0.007) and on a composite score of neuropsychological outcomes (p = 0.009).

CONCLUSION

The results of the present study indicate that this cognitive rehabilitation programme increases brain activity in the cerebellum of cognitively impaired patients with MS. The role of fMRI in the assessment of neurorehabilitation schemes warrants further investigation.