Jera Jeruc

The regulation of cysteine cathepsins and cystatins in human gliomas

Cysteine cathepsins play an important role in shaping the highly infiltrative growth pattern of human gliomas. We have previously demonstrated that the activity of cysteine cathepsins is elevated in invasive glioblastoma (GBM) cells in vitro, in part due to attenuation of their endogenous inhibitors, the cystatins. To investigate this relationship in vivo, we established U87‐MG xenografts in non‐obese diabetic (NOD)/severe combined immunodeficiency (SCID)‐enhanced green fluorescent protein (eGFP) mice. Here, tumor growth correlated with an elevated enzymatic activity of CatB both in the tumor core and at the periphery, whereas CatS and CatL levels were higher at the xenograft edge compared to the core. Reversely, StefB expression was detected in the tumor core, but it was generally absent in the tumor periphery, suggesting that down‐regulation of this inhibitor correlates with in vivo invasion. In human GBM samples, all cathepsins were elevated at the tumor periphery compared to brain parenchyma. CatB was also typically associated with angiogenic endothelia and necrotic areas. StefB was mainly detected in the tumor core, whereas CysC and StefA were evenly distributed, reflecting the observations in the xenografts. However, at the mRNA level, no differences in cathepsins and cystatins were observed between the tumor center and the periphery in both human biopsies and xenografts. Interestingly, in human tumors, cathepsin and stefin transcript levels correlated with CD68 and CXCR4 levels, but not with epidermal growth factor receptor (EGFR). Moreover, we reveal for the first time that an elevated StefA mRNA level is a highly significant prognostic factor for patient survival.

Lessons from Hepatocyte-Specific Cyp51 Knockout Mice: Impaired Cholesterol Synthesis Leads to Oval Cell-Driven Liver Injury

We demonstrate unequivocally that defective cholesterol synthesis is an independent determinant of liver inflammation and fibrosis. We prepared a mouse hepatocyte-specific knockout (LKO) of lanosterol 14α-demethylase (CYP51) from the part of cholesterol synthesis that is already committed to cholesterol. LKO mice developed hepatomegaly with oval cell proliferation, fibrosis and inflammation, but without steatosis. The key trigger was reduced cholesterol esters that provoked cell cycle arrest, senescence-associated secretory phenotype and ultimately the oval cell response, while elevated CYP51 substrates promoted the integrated stress response. In spite of the oval cell-driven fibrosis being histologically similar in both sexes, data indicates a female-biased down-regulation of primary metabolism pathways and a stronger immune response in males. Liver injury was ameliorated by dietary fats predominantly in females, whereas dietary cholesterol rectified fibrosis in both sexes. Our data place defective cholesterol synthesis as a focus of sex-dependent liver pathologies.

Disrupting Hepatocyte Cyp51 from Cholesterol Synthesis Leads to Progressive Liver Injury in the Developing Mouse and Decreases RORC Signalling

Development of mice with hepatocyte knockout of lanosterol 14α-demethylase (HCyp51−/−) from cholesterol synthesis is characterized by the progressive onset of liver injury with ductular reaction and fibrosis. These changes begin during puberty and are generally more aggravated in the knockout females. However, a subgroup of (pre)pubertal knockout mice (runts) exhibits a pronounced male prevalent liver dysfunction characterized by downregulated amino acid metabolism and elevated Casp12. RORC transcriptional activity is diminished in livers of all runt mice, in correlation with the depletion of potential RORC ligands subsequent to CYP51 disruption. Further evidence for this comes from the global analysis that identified a crucial overlap between hepatic Cyp51−/− and Rorc−/− expression profiles. Additionally, the reduction in RORA and RORC transcriptional activity was greater in adult HCyp51−/− females than males, which correlates well with their downregulated amino and fatty acid metabolism. Overall, we identify a global and sex-dependent transcriptional de-regulation due to the block in cholesterol synthesis during development of the Cyp51 knockout mice and provide in vivo evidence that sterol intermediates downstream of lanosterol may regulate the hepatic RORC activity.

Goodpasture's syndrome with concomitant immune complex mixed membranous and proliferative glomerulonephritis.

Classical Goodpastures (GP) syndrome is a monophasic illness characterized by pulmonary hemorrhage and rapidly progressive glomerulonephritis with linear IgG deposition along the glomerular and distal tubular basement membrane and estructive necrotizing diffuse extracapillary crescentic glomerulonephritis. The majority of patients have circulating anti-glomerular basement membrane (GBM) antibodies, detectable with standard anti-GBM ELISA. Concurrence of GP syndrome with proliferative glomerulonephritis has only rarely been described. In this report, for the first time we describe in a 21-year-old woman GP syndrome with 50% crescentic sclerosing glomerulonephritis with linear immunofluorescence characteristic of anti-GBM pathogenesis, combined with mixed membranous and membranoproliferative glomerulonephritis with granular immunofluorescence and subepithelial, mesangial and subendothelial deposits characterizing immune complex pathogenesis. The clinical picture was also unusual for GP syndrome, manifesting a recurrent but non-progressive course, nephrotic syndrome, normal renal function and low values of anti-GBM antibodies, identified only by novel more sensitive techniques.

Hidden Disease Susceptibility and Sexual Dimorphism in the Heterozygous Knockout of Cyp51 from Cholesterol Synthesis

We examined the genotype-phenotype interactions of Cyp51+/− mice carrying one functional allele of lanosterol 14α-demethylase from cholesterol biosynthesis. No distinct developmental or morphological abnormalities were observed by routine visual inspection of Cyp51+/− and Cyp51+/+ mice and fertility was similar. We further collected a large data-set from female and male Cyp51+/− mice and controls fed for 16 weeks with three diets and applied linear regression modeling. We used 3 predictor variables (genotype, sex, diet), and 39 response variables corresponding to the organ characteristics (7), plasma parameters (7), and hepatic gene expression (25). We observed significant differences between Cyp51+/− and wild-type mice in organ characteristics and blood lipid profile. Hepatomegaly was observed in Cyp51+/− males, together with elevated total and low-density lipoprotein cholesterol. Cyp51+/− females fed high-fat, high-cholesterol diet were leaner and had elevated plasma corticosterone compared to controls. We observed elevated hepatocyte apoptosis, mitosis and lipid infiltration in heterozygous knockouts of both sexes. The Cyp51+/− females had a modified lipid storage homeostasis protecting them from weight-gain when fed high-fat high-cholesterol diet. Malfunction of one Cyp51 allele therefore initiates disease pathways towards cholesterol-linked liver pathologies and sex-dependent response to dietary challenge.

Morphological and Functional Assessment of Oesophageal Mucosa Integrity in Children With Cystic Fibrosis.

Objectives: The aim of the study was to investigate morphological and functional characteristics of oesophageal epithelial barrier in children with cystic fibrosis (CF) with or without gastro-oesophageal reflux disease (GORD) in comparison to healthy controls. Methods: Oesophagogastroduodenoscopy with oesophageal biopsies and combined oesophageal multichannel intraluminal impedance-pH monitoring was performed in 17 children with CF (CFtot) with (CFgord) or without GORD (CFnorm). Histological combined severity score was calculated and widths of spaces between epithelial cells were measured. Basal impedance value was used to assess functional integrity of epithelial barrier. Results of each investigation were compared with a group of children without oesophageal disease. Results: CFtot, but also CFnorm, had more severe pathohistological changes included in the compound severity score than controls (0.75 ± 0.32 and 0.75 ± 0.20 vs 0.27 ± 0.25; P < 0.001 and P = 0.001, respectively). They also had more dilated intercellular spaces (2.6 &mgr;m ± 0.6 and 2.7 &mgr;m ± 0.5 vs 1.9 &mgr;m ± 0.2; P = 0.001 and P < 0.001, respectively). Baseline impedance values between proximal and distal pairs of electrodes were significantly lower in CFtot (2876 &OHgr; ± 484, 2590 &OHgr; ± 1013) and also in CFnorm (2922 &OHgr; ± 363, 2844 &OHgr; ± 457) than in controls (3703 &OHgr; ± 859, 3753 &OHgr; ± 1070) (P = 0.012 and P = 0.002; and P = 0.027 and P = 0.005, respectively). The treatment of CFgord with proton pump inhibitor increased, but did not normalise the baseline impedance values (2860 &OHgr; ± 560 to 3355 &OHgr; ± 750 and 2178 &OHgr; ± 1564 to 3057 &OHgr; ± 594). Conclusions: Children with CF had morphological and functional changes of oesophageal mucosal integrity even in the absence of GORD.

Genital anomalies in a patient with Treacher Collins syndrome

Karin Writzl,* Jera Jeruc, Michael Oldridge, Borut Peterlin, and Raoul C.M. Hennekam Institute of Medical Genetics, UMC, Ljubljana, Slovenia Department of Clinical Genetics, Great Ormond Street Hospital for Children, UCL, London, UK Faculty of Medicine, Institute of Pathology, University of Ljubljana, Ljubljana, Slovenia Molecular Genetics Laboratory, The Churchill Hospital, Oxford, UK Clinical and Molecular Genetics Unit, Institute of Child Health, UCL, London, UK Department of Paediatrics, AMC, Amsterdam, The Netherlands

Nephrology image/primary localized amyloidosis of the ureter

A 67-year-old woman with a history of recurrent urinary tract infections was admitted for investigation of intermittent gross hematuria and left flank pain. All blood tests were normal. Urinalysis revealed hematuria. Urine cultures were negative. Cystoscopy was unremarkable. Urine cytology was inconclusive; there were small clusters of urothelial cells showing mild atypia. Retrograde pyelography (Figure 1) and computed tomography urography were performed, showing hydroureteronephrosis above a tumor-like narrowing in the lower part of the ureter. A diagnosis of ureteral malignancy was made. She underwent left laparoscopic nephrectomy. Microscopic examination revealed chronic ureteritis and extensive deposition of red-orange amyloid deposits in Congo red staining (Figure 2) that displayed typical yellow-green birefringence under polarized light. Immunohistochemistry was positive for lambda light chains. Immunoelectrophoresis of serum and urine, Bence-Jones’s protein test, levels of immunoglobulins, and light chains were all normal. http://www.kidney-international.org n e p h r o l o g y i m a g e

Nephrology ImageNephrology image/primary localized amyloidosis of the ureter

A 67-year-old woman with a history of recurrent urinary tract infections was admitted for investigation of intermittent gross hematuria and left flank pain. All blood tests were normal. Urinalysis revealed hematuria. Urine cultures were negative. Cystoscopy was unremarkable. Urine cytology was inconclusive; there were small clusters of urothelial cells showing mild atypia. Retrograde pyelography (Figure 1) and computed tomography urography were performed, showing hydroureteronephrosis above a tumor-like narrowing in the lower part of the ureter. A diagnosis of ureteral malignancy was made. She underwent left laparoscopic nephrectomy. Microscopic examination revealed chronic ureteritis and extensive deposition of red-orange amyloid deposits in Congo red staining (Figure 2) that displayed typical yellow-green birefringence under polarized light. Immunohistochemistry was positive for lambda light chains. Immunoelectrophoresis of serum and urine, Bence-Jones’s protein test, levels of immunoglobulins, and light chains were all normal. http://www.kidney-international.org n e p h r o l o g y i m a g e