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SUMMARY Glomerulonephritis with organized microtubular monoclonal immunoglobulin deposits (GOMMID) and glomerulonephritis related to type I cryoglobulin are well-known but rare complications of B cell derived chronic lymphocytic leukaemia. In these disorders, monoclonal Ig have never been studied at the molecular level. We conducted a pathological and molecular analysis in a patient with chronic lymphocytic leukaemia, glomerulonephritis and a single circulating monoclonal Ig. Unusual IgG1κ kidney deposits were observed. The heavy and light chain variable region sequences of that cryoprecipitating monoclonal Ig were characterized. Light microscopy revealed glomerulonephritis typical of cryoglobulinaemia, with neutrophil and macrophage infiltration, endocapillary hyperplasia and few protein thrombi. Electron microscopic study clearly evidenced numerous subepithelial mixed granular and organized deposits with a unique microtubular organization, reminiscent of the GOMMID. The Ig molecule sequence revealed alterations of charge and hydrophobicity potentially promoting a crystal-like aggregation and the aggregation of microtubules.This description suggests that common mechanisms are involved in various forms of precipitation and/or deposition of complete Ig molecules, with a variable extent of organization and with a possible overlap between pathological patterns of either glomerulonephritis with microtubular deposits or type I cryoglobulinic glomerulonephritis. [ABSTRACT FROM AUTHOR]

Background: Aortitis is a group of disorders characterized by the inflammation of the aorta. The large-vessel vasculitides are the most common causes of aortitis. Aortitis long-term outcomes are not well known., Objectives: The purpose of this study was to assess the long-term outcome and prognosis of noninfectious surgical thoracic aortitis., Methods: This was a retrospective multicenter study of 5,666 patients with thoracic aorta surgery including 217 (3.8%) with noninfectious thoracic aortitis (118 clinically isolated aortitis, 57 giant cells arteritis, 21 Takayasu arteritis, and 21 with various systemic autoimmune disorders). Factors associated with vascular complications and a second vascular procedure were assessed by multivariable analysis., Results: Indications for aortic surgery were asymptomatic aneurysm with a critical size (n = 152 [70%]), aortic dissection (n = 28 [13%]), and symptomatic aortic aneurysm (n = 30 [14%]). The 10-year cumulative incidence of vascular complication and second vascular procedure was 82.1% (95% CI: 67.6%-90.6%), and 42.6% (95% CI: 28.4%-56.1%), respectively. Aortic arch aortitis (HR: 2.08; 95% CI: 1.26-3.44; P = 0.005) was independently associated with vascular complications. Descending thoracic aortitis (HR: 2.35; 95% CI: 1.11-4.96; P = 0.031) and aortic dissection (HR: 3.08; 95% CI: 1.61-5.90; P = 0.002) were independently associated with a second vascular procedure, while treatment with statins after aortitis diagnosis (HR: 0.47; 95% CI: 0.24-0.90; P = 0.028) decreased it. After a median follow-up of 3.9 years, 19 (16.1%) clinically isolated aortitis patients developed features of a systemic inflammatory disease and 35 (16%) patients had died., Conclusions: This multicenter study shows that 82% of noninfectious surgical thoracic aortitis patients will experience a vascular complication within 10 years. We pointed out specific characteristics that identified those at highest risk for subsequent vascular complications and second vascular procedures., Competing Interests: Funding Support and Author Disclosures The authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2023 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Apolipoprotein A1 amyloidosis (ApoAI) results from specific mutations in the APOA1 gene causing abnormal accumulation of amyloid fibrils in diverse tissues. The kidney is a prominent target tissue in ApoAI amyloidosis with a remarkable selectivity for the renal medulla. Here, we investigated six French families with ApoAI Glu34Lys, p.His179Profs∗47, and a novel p.Thr185Alafs∗41 variant revealing unprecedented clinical association of a glomerular with a retinal disease. Comprehensive clinicopathological, molecular and proteomics studies of numerous affected tissues ensured the correlation between clinical manifestations, including novel unrecognized phenotypes, and apoA-I amyloid deposition. These ophthalmic manifestations stemmed from apoA-I amyloid deposition, highlighting that the retina is a previously unrecognized tissue affected by ApoAI amyloidosis. Our study provides the first molecular evidence that a significant fraction of ApoAI amyloidosis cases with no family history result from spontaneous neomutations rather than variable disease penetrance. Finally, successful hepatorenal transplantation resulted in a life- and vision-saving measure for a 32-year-old man with a hitherto unreported severe ApoAI amyloidosis caused by the very rare Glu34Lys variant. Our findings reveal new modes of occurrence and expand the clinical spectrum of ApoAI amyloidosis. The awareness of glomerular and ocular manifestations in ApoAI amyloidosis should enable earlier diagnosis and avoid misdiagnosis with other forms of renal amyloidosis. Thus, documented apoA-I amyloid deposition in the retina offers new biological information about this disease and may change organ transplantation practice to reduce retinal damage in patients with ApoAI amyloidosis., (Published by Elsevier Inc.)

Background: IgA nephropathy (IgAN) often follows infections and features IgA mesangial deposition. Polymeric IgA deposits in the mesangium seem to have varied pathogenic potential, but understanding their pathogenicity remains a challenge. Most mesangial IgA1 in human IgAN has a hypogalactosylated hinge region, but it is unclear whether this is required for IgA deposition. Another important question is the role of adaptive IgA responses and high-affinity mature IgA antibodies and whether low-affinity IgA produced by innate-like B cells might also yield mesangial deposits., Methods: To explore the effects of specific qualitative variations in IgA and whether altered affinity maturation can influence IgA mesangial deposition and activate complement, we used several transgenic human IgA1-producing models with IgA deposition, including one lacking the DNA-editing enzyme activation-induced cytidine deaminase (AID), which is required in affinity maturation. Also, to explore the potential role of the IgA receptor CD89 in glomerular inflammation, we used a model that expresses CD89 in a pattern observed in humans., Results: We found that human IgA induced glomerular damage independent of CD89. When comparing mice able to produce high-affinity IgA antibodies with mice lacking AID-enabled Ig affinity maturation, we found that IgA deposition and complement activation significantly increased and led to IgAN pathogenesis, although without significant proteinuria or hematuria. We also observed that hinge hypoglycosylation was not mandatory for IgA deposition., Conclusions: In a mouse model of IgAN, compared with high-affinity IgA, low-affinity innate-like IgA, formed in the absence of normal antigen-driven maturation, was more readily involved in IgA glomerular deposition with pathogenic effects., (Copyright © 2019 by the American Society of Nephrology.)

Background: It remains presently unclear whether disease progression in colorectal carcinoma (CRC), from early, to invasive and metastatic forms, is associated to a gradual increase in genetic instability and to a scheme of sequentially occurring Copy Number Alterations (CNAs)., Methods: In this work we set to determine the existence of such links between CRC progression and genetic instability and searched for associations with patient outcome. To this aim we analyzed a set of 162 Chromosomal Instable (CIN) CRCs comprising 131 primary carcinomas evenly distributed through stage 1 to 4, 31 metastases and 14 adenomas by array-CGH. CNA profiles were established according to disease stage and compared. We, also, asked whether the level of genomic instability was correlated to disease outcome in stage 2 and 3 CRCs. Two metrics of chromosomal instability were used; (i) Global Genomic Index (GGI), corresponding to the fraction of the genome involved in CNA, (ii) number of breakpoints (nbBP)., Results: Stage 1, 2, 3 and 4 tumors did not differ significantly at the level of their CNA profiles precluding the conventional definition of a progression scheme based on increasing levels of genetic instability. Combining GGI and nbBP,we classified genomic profiles into 5 groups presenting distinct patterns of chromosomal instability and defined two risk classes of tumors, showing strong differences in outcome and hazard risk (RFS: p = 0.012, HR = 3; OS: p < 0.001, HR = 9.7). While tumors of the high risk group were characterized by frequent fractional CNAs, low risk tumors presented predominantly whole chromosomal arm CNAs. Searching for CNAs correlating with negative outcome we found that losses at 16p13.3 and 19q13.3 observed in 10% (7/72) of stage 2-3 tumors showed strong association with early relapse (p < 0.001) and death (p < 0.007, p < 0.016). Both events showed frequent co-occurrence (p < 1x10-8) and could, therefore, mark for stage 2-3 CRC susceptible to negative outcome., Conclusions: Our data show that CRC disease progression from stage 1 to stage 4 is not paralleled by increased levels of genetic instability. However, they suggest that stage 2-3 CRC with elevated genetic instability and particularly profiles with fractional CNA represent a subset of aggressive tumors.

Background: Sirolimus (SRL) is a potent immunosuppressant used in organ transplantation. It is known to decrease vascular endothelial growth factor (VEGF) synthesis, making it an interesting treatment option for transplant patients who develop Kaposi sarcoma or other malignant diseases. Because VEGF plays a key role in glomerular function and vascular remodelling, we determined the effect of SRL on renal VEGF expression., Methods: Using immunohistochemistry and quantitative image analysis, we examined renal VEGF expression in routine kidney biopsies performed at 1 year post-transplant in the CONCEPT study, a prospective randomized study comparing a cyclosporine (CsA)-based regimen to a SRL-based regimen in association with mycophenolate mofetil (MMF)., Results: A total of 74 patients were included in this substudy; 35 were randomized to the CsA group and 39 to the SRL group. Using continuous variables, the mean percentage of glomerular VEGF expression at Week 52 was significantly lower in the SRL group (14.7 ± 13%) compared to CsA group (21.2 ± 14%: P = 0.02). The percentage of glomerular VEGF expression at Week 52 was not influenced by recipient or donor age, gender, renal function, CsA dose, CsA blood level, SRL dose or SRL blood level. It was significantly lower in patients with a proteinuria over versus below 0.5 g/day (11.58 ± 7.9 versus 19.45 ± 15.53; P = 0.036)., Conclusions: There is emerging evidence that the VEGF system can play either a beneficial or a detrimental role depending on the specific pathologic situations. Therefore, modulating the renal VEGF axis by using an SRL-based regimen may influence the evolution of kidney injury associated with renal transplantation.

Objectives: To identify juvenile idiopathic arthritis (JIA) patients who developed IBD during treatment with anti-TNF-alpha agents and better characterize the IBD clinical and pathological presentation., Methods: A retrospective French multicentre study included patients with a diagnosis of JIA according to the ILAR criteria who developed IBD while under anti-TNF-alpha therapy before 18 years of age. Intestinal biopsies were collected and reviewed by the same pathologist., Results: Eight patients were included. They had been treated with etanercept from 11 to 78 months before IBD onset. Gastro-intestinal symptoms included abdominal pain (six patients), diarrhoea (four patients), anorexia (four patients), anal abscess (three patients) and oral ulcers (one patient). Five patients presented with Crohn's disease (CD) and three with indeterminate IBD, of whom four had severe pancolitis. Clinical remission of IBD was obtained in all patients after discontinuation of etanercept and initiation of IBD-specific therapy, including infliximab in six patients., Conclusion: IBD must be suspected in JIA patients treated with etanercept who develop intestinal symptoms, including anal abscess. This series raises the possibility of a relationship between etanercept therapy and the occurrence of IBD in a subset of patients with JIA.

Aim: To develop and characterize by imaging and pathological examination a new immunocompetent rat model of head and neck squamous cell carcinoma (HNSCC)., Study Design: Prospective animal research., Materials and Methods: Frozen specimens of HNSCC induced chemically by 4-nitroquinoline 1 oxide (4-NQO) in Sprague Dawley rats were used for the first graft. Serial allografts were then performed with fresh specimens of tumor in twenty-five Sprague Dawley rats. A specimen of tumor (100 mm3) was picked up by head and neck dissection during an autopsy. The graft was performed in a subcutaneous manner, in the ventral part of the neck, using an incision of 4 mm, through the masseter muscle. Tumors were clinically measured once a week and volumes were calculated. 2-[18F]Fluoro-2-deoxy-D-glucose positron emission tomography coupled with computed tomography (FDG-PET/CT) was performed on days 14 and 30 after the graft. Rats were euthanized and pathological features were assessed using hematoxylin-eosin (HE) staining and immunohistochemistry markers to characterize the tumor., Results: An 80% take rate was achieved using fresh tumor specimens. Tumors grew rapidly; the mean tumoral volume was 1.013 cm3 on day 14 and 7.994 cm3 on day 30. FDG-PET/CT imaging targeted regions of metabolically active tumor. It showed a uniform uptake of 18F-FDG on day 14 and a large area of central necrosis on day 30. Pathological examinations showed a typical squamous cell carcinoma, with similar immunohistochemical analyses to the human squamous cell carcinoma., Conclusion: We propose a new allograft HNSCC rat model which is easily reproducible and rapidly obtained in comparison to that induced chemically with 4-NQO. This model was developed in immunocompetent rats, with similar conditions to human carcinogenesis and could be used for testing new therapeutics.

Background: In an orthotopic rat osteosarcoma model, histological and molecular findings were compared with the results of non-invasive imaging methods to assess disease progression at the primary site, the pattern of metastatic dissemination and the chemoresistance phenotype., Materials and Methods: Primary tumor engraftment, vascularization, growth and metastatic spread were evaluated using 18FDG tomoscintigraphy. Bone neoformation in the primary tumor and metastasis was determined using 18FNa confirmed by classical histological studies. Chemoresistance phenotype was assessed by analysis of MDR1 and MRP1 genes expression compared to 99mTc MIBI imaging., Results: 99mTc MIBI imaging correlated with the overexpression of the MDR1 and MRP1 genes. 18FDG, 18FNa and 99mTc tomoscintigraphies revealed that the pattern of vascularization, bone neoformation and hematogeneous metastatic dissemination in our animal model mimics its human counterpart., Conclusion: Multimodality, non-invasive imaging is a valid surrogate marker of histological and molecular characteristics in an orthotopic osteosarcoma model in immunocompetent rats; it allows extensive in vivo follow-up of osteosarcoma, including longitudinal analysis of chemoresistance.

Tumor progression depends on the angiogenic switch. In this review, we recapitulate the molecular mechanisms involved in this angiogenic switch. The rat osteosarcoma model employed would permit further studies in the sequential events leading to initial recruitment of blood vessels and could lead to development of an angiogenesis-based panel of circulating blood cells (endothelial cells, endothelial progenitor cells and accessory cells) that can be quantified and used to detect microscopic tumors or to follow the efficacy of antiangiogenic therapy. Such a result would lead to the possibility of early therapy in cancer progression.

Several genes have been involved in drug resistance but none are currently used in the drug decision process. To address this problem, mRNA levels were measured for the 5-fluorouracil metabolism-related genes, thymidylate synthase, thymidine phosphorylase and dihydropyrimidine dehydrogenase in tumor samples of 40 patients with synchronous metastatic colon cancer by quantitative RT-PCR. Drug response and overall survival were also obtained for each patient. A logistic regression model was defined to calculate a response predicting score (RPS) with gene expression levels. This RPS split responders from nonresponders as, at the best statistical threshold (0.35), the area of receiver operating characteristic (ROC) curve established with this method was 0.82 and sensitivity and specificity were respectively 100% and 65.4%. Furthermore patients with scores above 0.35 tended to have better overall survival than those with a score less than 0.35 (p = 0.09).

Antiangiogenesis or destruction of tumor neovessels is an effective strategy to prevent tumor growth. Endostatin, one of the many inhibitors of angiogenesis that have been discovered, has shown conflicting results in preclinical assays. We studied the therapeutic potential of lipid/DNA complexes consisting of cationic liposomes and an endostatin-coding plasmid (Endo cDNA/CLP) in an orthotopic osteosarcoma model in rats. Empty plasmid without the endostatin gene complexed with cationic liposomes served as control. Animals were treated intravenously three times a week starting on the day tumors were detectable by (18)FDG tomoscintigraphy. During treatment, tumor progression was followed by PET scan and angioscintigraphy, and the effects of antivascular therapy on primary tumor, metastases, and tumor vascular density were confirmed by histologic analysis. Our results demonstrate that therapy using Endo cDNA/CLP is associated with pronounced delay in tumor growth. Moreover, it effectively prevented the occurrence of lung metastases, the major reason for bad prognosis and death in osteosarcoma patients. This approach could be used as an adjuvant therapy for osteosarcoma.

Context: Microsatellite instability (MSI) due to defective mismatch repair (MMR) genes has been reported in the majority of colorectal tumors from patients with hereditary nonpolyposis colorectal cancer syndrome and in 10% to 15% of sporadic colorectal cancers. The identification of cancers associated with MSI requires classical molecular testing as the gold standard., Objective: The aim of this study was to evaluate the role of immunohistochemistry with antibodies directed against 4 MMR proteins as a screening tool for carcinomas with MSI., Methods: In this study, 204 formalin-fixed, paraffin-embedded colorectal carcinomas were examined for MMR protein expression (hMLH1, hMSH2, hMSH6, and hPMS2) and analyzed for MSI (MSI-H indicates at least 2 of 6 markers affected). These results were correlated with histopathologic parameters., Results: Immunohistochemical analysis revealed that loss of expression of at least 1 protein was present in 17% of cases. One hundred percent of carcinomas that showed high instability (MSI-H) showed loss of expression of hMLH1, hMSH2, or hMSH6. Loss of expression of 2 proteins was present in 59.4% of MSI-H cases, with only 2 combinations, namely, hMLH1/hPMS2 and hMSH2/hMSH6. Isolated loss of hMSH6 expression was present in 2 MSI-H cases., Conclusions: These findings confirm that examination of MMR protein expression by immunohistochemistry is a simple method to diagnose colorectal cancer with MSI. Our data suggest that the study of hMSH6 may be useful, in addition to hMLH1 and hMSH2. Moreover, immunohistochemistry could represent a screening method with which to direct research on the mutations of MMR genes observed in hereditary nonpolyposis colorectal cancer syndrome.

Background: Renal angiomyolipoma is a benign tumor histologically characterized by proliferation of spindle cells, epithelioid cells, and adipocytic cells in concert with many thick-walled blood vessels. To add further diagnostic confusion, an epithelioid cell-predominant variant of renal angiomyolipoma has recently been described. HMB-45 immunoreactivity correlates with ultrastructural striated organelles that closely resemble premelanosomes, although no evidence of melanogenesis has been documented in this tumor., Objective: To further characterize the immunophenotypic and ultrastructural profile of renal angiomyolipoma based on phenotypic cell type (epithelioid, spindle, and adipocytic cell)., Design: Formalin-fixed, paraffin-embedded tissues from 27 renal angiomyolipomas and 8 renal cell carcinomas were immunostained with monoclonal antibodies to the melanoma-associated antigens HMB-45, HMB-50, NKI/C3 (CD63), and tyrosinase; the smooth muscle-related antigens calponin and muscle-specific actin (HHF-35); S100; and cytokeratin (CK). All renal angiomyolipomas were also immunostained with a polyclonal antibody to renin. Ultrastructural examination was performed on 9 selected cases., Results: All renal angiomyolipomas stained positive for HMB-45, HMB-50, NKI/C3, muscle-specific actin (HHF-35), and calponin. Overall, HMB-45, HMB-50, and NKI/C3 preferentially stained the epithelioid cells. Tyrosinase staining was present in 50% of the renal angiomyolipomas with adequate tissue for staining (12 of 24 cases); positive staining and intensity paralleled HMB-45, HMB-50, and NKI/C3. Muscle-specific actin (HHF-35) and calponin preferentially stained the spindle cells. The adipocytic cells stained positive for both melanoma-associated antigens and smooth muscle antigens. Epithelioid cells, spindle cells, and adipocytic cells were CK, S100, and renin negative. Ultrastructural findings paralleled immunohistochemical staining patterns. Premelanosome-like organelles and electron dense granules were more readily detected in the epithelioid cells within the tumor, whereas ultrastructural characteristics of smooth muscle cells were more easily found in the spindle cells. All renal cell carcinomas stained positive for CK, NKI/C3 staining was variable, and all were negative for HMB-45, HMB-50, smooth muscle actin (HHF-35), and calponin., Conclusion: In renal angiomyolipoma, the epithelioid and spindle cells have preferential staining patterns for melanoma-associated antigens versus smooth muscle antigens, respectively. Positivity in renal angiomyolipoma for HMB-50, NKI/C3, and tyrosinase, in addition to HMB-45, provides evidence for the presence of different melanoma-associated gene products. Immunophenotypic overlap of the 3 histologically distinct renal angiomyolipoma cell populations suggests a common cell line, supporting a unitarian concept for renal angiomyolipoma. Ultrastructural characteristics of the 3 renal angiomyolipoma cell phenotypes parallel the immunophenotype, giving further support to a common cell line. Our study lends further credence to the perivascular epithelioid cell concept as proposed by Bonetti and colleagues.

Renal involvement in von Hippel-Lindau (VHL) disease has emerged as the most prevalent cause of death in this hereditary disorder. In a group of 43 VHL patients (23 unrelated families) with renal lesions we examined whether severity of renal disease is affected by parental inheritance and VHL subtype (1, without pheochromocytoma; 2, with pheochromocytoma). We also tested whether and how nephron-sparing surgery could be applied. Renal involvement comprised multiple cysts and bilateral and multifocal carcinomas (RCC) which were detected by screening in 38 patients, at 30.5 (14 to 62) years of age. The severity of the renal disease was similar in VHL type 1 (79% of the pedigrees) and 2 (21%). It was not influenced by the sex of the carrier. Twenty-nine patients were operated on at a mean age of 33.6 years: 21 patients (28 kidneys or 61% of all operated kidneys) underwent nephron-sparing surgery, 4 had complete ablation of involved kidneys and thus required dialysis, 3 had uninephrectomy and 1 had cyst fenestration. Vascular thrombosis was the most severe early complication. It occurred in 4 of 9 kidneys treated by ex vivo surgery. During a median follow-up of 29 months, local recurrence occurred in 5 of 21 (24%) patients treated by nephron-sparing surgery, whereas 2 developed metastasis. Chronic renal failure (creatinine > 120 mumol/liter) affected 11 patients; in 9 of them, it was due to sequelae of surgery. In conclusion, screening of RCC and nephron-sparing surgery are of value in VHL patients. However, indications of ex vivo surgery should be drastically restricted and renal sequelae are not uncommon. Renal followup is required because of the risk of recurrence.

To make liver biopsy unnecessary in certain cases, PGA (P, prothrombin time; G, gamma-glutamyl transpeptidase; A, apoliprotein AI), a simple biological index combining a specific test for severe liver disease (prothrombin time), a sensitive test of alcoholic liver disease (serum gamma-glutamyl transpeptidase), and a test for liver fibrosis (serum apolipoprotein AI), was evaluated in a training sample of 333 drinkers and validated in 291 other drinkers. All patients underwent an intercostal liver biopsy, and the specimen was independently read by two pathologists. The PGA index varied from 0 to 12. When PGA was less than or equal to 2, the probability of cirrhosis was 0% and the probability of normal liver or minimal changes 83%. Conversely, when PGA was greater than or equal to 9, the probability of normal liver or minimal changes was 0% and the probability of cirrhosis 86%. These values did not vary between training and validation periods, between asymptomatic vs. symptomatic subjects or between PGA at admission vs. PGA 1 week later. This index could be useful for general practitioners in identifying subjects at high risk for severe alcoholic liver disease.

Apolipoprotein A-I and apolipoprotein A-II, the two major protein components of the high-density lipoproteins, were visualized in human arteries using an immunofluorescence technique. Apolipoprotein A-I and apolipoprotein A-II were codeposited into the intima and upper media of normal arteries of atherosclerotic patients. The amount of deposits increased in fatty streaks. In atherosclerotic plaques, apolipoproteins accumulated around the necrotic material. These two apoproteins were present in the extracellular matrix as well as in the foam cells surrounding the atherosclerotic lesions. The concomitant intracellular localization of apolipoprotein A-I and of apolipoprotein A-II in the cytoplasm of foam cells supports the hypothesis that extracellular high-density lipoprotein particles are internalized in the macrophages during the atheromatous process.