Apparent preferential loss of heterozygosity at TSC2 over TSC1 chromosomal region in tuberous sclerosis hamartomas

To investigate the molecular mechanisms of tuberous sclerosis (TSC) histopathologic lesions, we have tested for loss of heterozygosity the two TSC loci (TSC1 and TSC2) and seven tumor suppressor gene-containing regions (TP53, NF1, NF2, BRCA1, APC, VHL, and MLM) in 20 hamartomas from 18 TSC patients. Overall, eight angiomyolipomas, eight giant cell astrocytomas, one cortical tuber, and three rhabdomyomas were analyzed. Loss of heterozygosity at either TSC locus was found in a large fraction of the informative patients, both sporadic (7/14) and familial (1/4). Interestingly, a statistically significant preponderance of loss of heterozygosity at TSC2 was observed in the sporadic group (P < 0.01). Among the possible explanations considered, the bias in the selection for TSC patients with the most severe organ impairment seems particularly appealing. According to this view, a TSC2 defect might confer a greater risk for early kidney failure or, possibly, a more rapid growth of a giant cell astrocytoma. None of the seven antioncogenes tested showed loss of heterozygosity, indicating that the loss of either TSC gene product may be sufficient to promote hamartomatous cell growth. Finally, the observation of loss of heterozygosity at different markers in an astrocytoma and in an angiomyolipoma from the same patient might suggest the multifocal origin of the second-hit mutation. Genes Chromosom Cancer 15:18–25 (1996). © 1996 Wiley-Liss, Inc.     

International trends in hepatocellular carcinoma incidence, 1978–2012

Primary liver cancer, the major histology of which is hepatocellular carcinoma (HCC), is the second leading cause of cancer death worldwide. We comprehensively examined recent international trends of primary liver cancer and HCC incidence using population-based cancer registry data. Incidence for all primary liver cancer and for HCC by calendar time and birth cohort was examined for selected countries between 1978 and 2012. For each successive 5-year period, age-standardized incidence rates were calculated from Volumes V to XI of the Cancer Incidence in Five Continents (CI5) series using the online electronic databases, CI5plus. Large variations persist in liver cancer incidence globally. Rates of liver cancer remain highest in Asian countries, specifically in the East and South-East, and Italy. However, rates in these high-risk countries have been decreasing in recent years. Rates in India and in most countries of Europe, the Americas and Oceania are rising. As the population seroprevalence of hepatitis B virus (HBV) continues to decline, we anticipate rates of HCC in many high-risk countries will continue to decrease. Treatment of hepatitis C virus (HCV) is likely to bring down rates further in some high-rate, as well as low-rate, countries with access to effective therapies. However, such gains in the control of liver cancer are at risk of being reversed by the growing obesity and diabetes epidemics, suggesting diabetes treatment and primary prevention of obesity will be key in reducing liver cancer in the longer-term.     

The effect of chronic neuroglycopenia on resting state networks in GLUT1 syndrome across the lifespan

Glucose transporter type I deficiency syndrome (GLUT1DS) is an encephalopathic disorder due to a chronic insufficient transport of glucose into the brain. PET studies in GLUT1DS documented a widespread cortico‐thalamic hypometabolism and a signal increase in the basal ganglia, regardless of age and clinical phenotype. Herein, we captured the pattern of functional connectivity of distinct striatal, cortical, and cerebellar regions in GLUT1DS (10 children, eight adults) and in healthy controls (HC, 19 children, 17 adults) during rest. Additionally, we explored for regional connectivity differences in GLUT1 children versus adults and according to the clinical presentation. Compared to HC, GLUT1DS exhibited increase connectivity within the basal ganglia circuitries and between the striatal regions with the frontal cortex and cerebellum. The excessive connectivity was predominant in patients with movement disorders and in children compared to adults, suggesting a correlation with the clinical phenotype and age at fMRI study. Our findings highlight the primary role of the striatum in the GLUT1DS pathophysiology and confirm the dependency of symptoms to the patients' chronological age. Despite the reduced chronic glucose uptake, GLUT1DS exhibit increased connectivity changes in regions highly sensible to glycopenia. Our results may portrait the effect of neuroprotective brain strategy to overcome the chronic poor energy supply during vulnerable ages.     

Continuous intravenous infusion of TRH-T: clinical, cardiovascular and endocrinological effects

Seven patients, six suffering from amyotrophic lateral sclerosis (ALS) and one from Friedreich ataxia, were treated with a placebo i.v. infusion during the first day and with TRH-T i.v. infusion at a rate of 2 mg/h for 8 h daily (total daily dosage 16 mg) on the 2 consecutive days. Continuous blood pressure (BP) and EKG monitorings were performed during 3 days infusion. Blood samples were collected for endocrinological evaluations. The neurological evaluation after acute TRH-T treatment showed an objective improvement in 3 of the 8. We found significantly higher values of systolic (max. difference of 10.1 mm Hg) and diastolic (max. difference of 8.8 mm Hg) BP than during placebo, beginning from the 5th h of the infusion (p less than 0.05). A trend in progressive increase of the heart rate (HR) reached statistical significance (p less than 0.01) at the 8th h of the second TRH-T infusion. The cardiovascular changes during the i.v. continuous TRH-T infusions were clinically irrelevant and never required the interruption of the treatment.     

Spatial distribution of mast cells around vessels and glands in human gastric carcinoma

The spatial distribution of mast cells inside the tumor stroma has been little investigated. In this study, we have evaluated tumor mast cells (MCs) distribution in gastric cancer through the analysis of the morphological features of the spatial patterns generated by these cells, including size, shape, and architecture of the cell pattern. The pattern of distribution of tryptase- and chymase-positive MCs around the blood vessels and gastric glands in human gastric adenocarcinoma samples was investigated by immunohistochemical techniques and by introducing a quantitative approach to characterize the spatial distribution of MCs. In human gastric cancer, both chymase-positive MC and vessels exhibited significant deviations from randomness for what it concerns their spatial relationship with gastric parenchyma. As indicated by cell-to-gland distances shorter than expected by chance, in grade II samples a preferential localization of chymase-positive MC near the gastric glands was observed. Interestingly, the same type of spatial association was exhibited by vessels in grade IV samples, where vessel-to-gland distances shorter than expected by chance were observed. These two findings allow to speculate about a sequence of events in which a subpopulation of MC is first recruited around gastric parenchyma to drive the subsequent development of a vascular support to the tissue.     

Complex epileptic (Foix–Chavany–Marie like) syndrome in a child with neurofibromatosis type 1 (NF1) and bilateral (opercular and paracentral) polymicrogyria

The association of brain malformations and symptomatic epilepsy in the setting of neurofibromatosis type 1 (NF1) is rarely reported. When it occurs, patients can present clinically with infantile spasms, focal seizures, generalized tonic clonic seizures or atypical absences. We report on a 10-year-old (molecularly proven) NF1 girl manifesting a complex epileptic syndrome resembling the Foix–Chavany–Marie spectrum (also known as opercular syndrome) associated with bilateral (opercular and paracentral lobular) polymicrogyria (PMG). Anecdotal cases of unilateral PMG in the setting of NF1 have been described in association with other-than-opercular epileptic syndromes. The typical clinical opercular syndrome consisting in mild mental retardation, epilepsy and pseudobulbar palsy is usually associated to bilateral perisylvian PMG (BPP)
Conclusion: To the best of our knowledge, the complex epileptic syndrome hereby reported has not been previously recorded in the setting of NF1. In addition, the present girl manifested all the clinical features of an opercular syndrome but had an asymmetrical PMG (not a BPP).