Utilizing the MEST score for prognostic staging in IgA nephropathy

Background The Oxford classification/MEST score is an established histopathologic scoring system for patients with IgA nephropathy (IgAN). The objective of this study was to derive a prognostic model for IgAN based on the MEST score and histopathologic features. Methods A total of 306 patients with biopsy-proven primary IgAN were included. Histopathologic samples were retrieved from the Norwegian Kidney Biopsy Registry and reclassified according to the Oxford classification. The study endpoint was end-stage renal disease (ESRD). Patients were subclassified into three risk models based on histologic features (Model A), a composite score calculated from the adjusted hazard ratio values (Model B), and on quartiles (Model C). Results The mean follow-up time was 16.5 years (range 0.2–28.1). In total, 61 (20%) patients reached ESRD during the study period. Univariate analysis of M, E, S, T and C lesions demonstrated that all types were associated with an increased risk of ESRD; however, a multivariate analysis revealed that only S, T and C lesions were associated with poor outcomes. Statistical analysis of 15-year data demonstrated that Models A and B were as predictive as the MEST score, with an area-under-the-curve at 0.85. The Harrel c index values were 0.81 and 0.80 for the MEST score and Models A and B, respectively. In the present cohort, adding C lesions to the MEST score did not improve the models prognostic value. Conclusions Patients can be divided into risk classes based on their MEST scores. Histopathologic data provide valuable prognostic information at the time of diagnosis. Model B was the most suitable for clinical practice because it was the most user-friendly.publishedVersio

Prognostic factors in anti-neutrophil cytoplasmic antibody-associated glomerulonephritis with severe glomerular sclerosis: a national registry-based cohort study

Background. Classification of patients with anti-neutrophil cytoplasmic antibody-associated glomerulonephritis (ANCA-GN) into histological classes is useful for predicting a patient’s risk of progression to end-stage renal disease (ESRD). However, even in the worst prognostic group, the 5-year end-stage renal disease-free survival rate is as high as 50%. Objectives. To investigate those prognostic factors indicative of progression to ESRD in patients with ANCA-GN and sclerosing histology. Methods. Patients from the Norwegian Kidney Biopsy Registry between 1991 and 2012 who had biopsy verified pauci-immune glomerulonephritis, positive ANCA serology, and sclerosing histology were included. Cases with ESRD during follow-up were identified via linkage with the Norwegian Renal Registry. Potential prognostic factors with relevant cut-offs were compared in patients with and without progression to ESRD during follow-up. Results. Of 23 included patients, 10 progressed to ESRD. ESRD patients had a lower initial estimated glomerular filtration rate (eGFR; 21 versus 52 ml/min/1.73 m2) and a lower percentage of normal glomeruli (4% versus 15%). Five-year risks of ESRD with eGFR >15 versus ≤15 ml/min/1.73 m2 were 77% and 15%, with percentage normal glomeruli >10% versus ≤10%, 83% and 39%. Conclusions. eGFR and percentage of normal glomeruli are strong risk factors for ESRD in ANCA-GN with sclerosing histology.publishedVersio

Validation of two IgA nephropathy risk-prediction tools using a cohort with a long follow-up

Background: Recently, two immunoglobulin A (IgA) nephropathy-prediction tools were developed that combine clinical and histopathologic parameters. The International IgAN Prediction Tool predicts the risk for 50% declines in the estimated glomerular filtration rate or end-stage kidney disease up to 80 months after diagnosis. The IgA Nephropathy Clinical Decision Support System uses artificial neural networks to estimate the risk for end-stage kidney disease. We aimed to externally validate both prediction tools using a Norwegian cohort with a long-term follow-up. Methods: We included 306 patients with biopsy-proven primary IgA nephropathy in this study. Histopathologic samples were retrieved from the Norwegian Kidney Biopsy Registry and reclassified according to the Oxford Classification. We used discrimination and calibration as principles for externally validating the prognostic models. Results: The median patient follow-up was 17.1 years. A cumulative, dynamic, time-dependent receiver operating characteristic analysis showed area under the curve values ranging from 0.90 at 5 years to 0.83 at 20 years for the International IgAN Prediction Tool, while time-naive analysis showed an area under the curve value at 0.83 for the IgA Nephropathy Clinical Decision Support System. The International IgAN Prediction Tool was well calibrated, while the IgA Nephropathy Clinical Decision Support System tends to underestimate risk for patients at higher risk and overestimates risk in the lower risk categories. Conclusions: We have externally validated two prediction tools for IgA nephropathy. The International IgAN Prediction Tool performed well, while the IgA Nephropathy Clinical Decision Support System has some limitations.publishedVersio

pRb2/p130 protein expression and RBL2 mutation analysis in Burkitt lymphoma from Uganda

<p>Abstract</p> <p>Background</p> <p>The members of the retinoblastoma protein family, pRb, p107 and pRb2 (p130), are central players in controlling the cell cycle. Whereas disturbed function of pRb is commonly seen in human cancers, it is still an open question whether pRb2 is involved in tumorigenic processes. However, altered subcellular localization of pRb2 and mutations in the pRb2-encoding gene <it>RBL2 </it>have been described for some tumours, including Burkitt lymphomas (BL).</p> <p>Methods</p> <p>We retrieved 51 biopsy specimens of endemic BL cases from Uganda. The expression of pRb2 was determined by immunohistochemistry. Exons 1922 of the <it>RBL2 </it>gene, the region known to contain a nuclear localization signal, were screened for mutations by PCR amplification and direct DNA sequencing.</p> <p>Results</p> <p>Nearly all of our cases (84.0%) were positive for pRb2 protein expression although this protein is a marker for growth arrest and Burkitt lymphoma is characterized by a high proliferation rate. Of the positive cases, 73.8% were scored as expressing the protein at a high level. Subcellular pRb2 localization was predominantly nuclear and no cases with expression restricted to the cytoplasm were observed. We did not detect any <it>RBL2 </it>mutations in the part of the gene that encodes the C-terminal end of the protein.</p> <p>Conclusion</p> <p>The majority of endemic BL cases from Uganda express pRb2, but somatic <it>RBL2 </it>mutations affecting the protein's nuclear localization signal appear to be rare.</p

Serum levels of the IL-6 family of cytokines predict prognosis in renal cell carcinoma (RCC)

Purpose An improved understanding of RCC immunology should shed further light on RCC tumor biology. Our objective was to study to what extent serum levels of the IL-6 family of cytokines at diagnosis were relevant to survival. Methods A total of 118 consecutively patients with RCC, in which the tumor was surgically removed at Haukeland University Hospital during the period from 2007 to 2010, were included. The patients were followed-up for 10 years. The morning before surgery blood was sampled and serum frozen, with levels of IL-6, IL-27, IL-31, OSM, CNTF, IL-6Rα and gp130 determined. Results Among patients with the highest quartile of IL-6 (> 8 pg/ml) (n = 29), six of nine who had metastasis at diagnosis had such high IL-6 values. Among presumed radically treated patients, a high IL-6 and IL-27 strongly predicted recurrence. In particular, the predictions among patients with large (diameter > 7 cm) tumors were excellent regarding both IL-6 and IL-27 values. High gp130 serum levels predicted an overall survival (OS) among RCC patients with large tumors. Patients with a high IL-6 exhibited a strong expression of IL-6 in endothelial- and vascular smooth muscle cells. Moreover, the level of intra-tumoral CD3-positive cells predicted survival. Conclusions IL-6 and IL-27 seem to play a role in RCC biology. IL-6 enables the pinpointing of metastatic condition at diagnosis, as well as together with IL-27, the predicting of survival and recurrence. Endothelial cells and vascular smooth muscle cells are both suggested as important sources of IL-6.publishedVersio

The levels of IL-6 and soluble IL-33R are increased in the renal vein during surgery for clear cell renal cell carcinoma

Purpose The main aim was to map serum levels of IL-1/IL-6 family cytokines and relevant receptors from serum samples taken across treatment in patients with Renal Cell Carcinoma (RCC). Additionally, we explored the possible interactions between these measurements, immunohistochemistry and intratumoral blood flow. Methods We included 40 patients undergoing open surgery for renal tumors. Blood samples were collected before, during (taken simultaneously from a peripheral site and the renal vein (RV) before clamping) and after surgery. Samples were analyzed for IL-6, IL-27, IL-31, OSM, TNF-α, serum (s)-gp130, s-IL-6Rα, s-IL-33R, IL-1Rα and VEGF. All 35 RCC tumors were histologically subtyped as clear cell (CCRCC), papillary or chromophobe. Immunohistochemistry for the CCRCC group included expression of IL-6/IL-6R. Intratumoral blood flow was determined by calculating intratumoral contrast enhancement on preoperative computerized tomography (CT) imaging. Results In the CCRCC patients, the intraoperative RV concentration of IL-6 was significantly higher than in both the preoperative and postoperative samples (p = 0.005 and p = 0.032, respectively). Furthermore, the intraoperative ratio showed significantly higher levels of IL-6 in the RV than in the simultaneously drawn peripheral sample. Immunohistochemistry showed general expression of IL-6 (23/24) in both tumor cells and the vasculature (20/23). Moreover, s-IL-6R was expressed in tumor cells in 23/24 studied patients. Increased blood flow in the CCRCC tumors predicted increased IL-6 levels in the RV (p < 0.001). The other cytokines and receptors showed an overall stability across the measurements. However, the intraoperative ratios of IL-33R and gp130 showed significantly higher levels in the RV. Conclusion Serum levels of IL-6 increased during surgery. Intraoperative IL-6 and s-IL-33R values were higher in the RV compared to the periphery, suggesting secretion from the tumor or tumor microenvironment itself. Supportive of this is an almost general expression of IL-6/s-IL-6R in tumor cells and IL-6 in vasculature in the tumor microenvironment. Other studied cytokines/receptors were remarkably stable across all measurements.publishedVersio

The activity of pregnancy-associated plasma protein A (PAPP-A) as expressed by immunohistochemistry in atherothrombotic plaques obtained by aspiration thrombectomy in patients presenting with a ST-elevation myocardial infarction: a brief communication

<p>Abstract</p> <p>Background</p> <p>The expression of pregnancy-associated plasma protein A (PAPP-A) was identified by immunohistochemistry (IHC) in culprit atherothrombotic plaque specimens harvested from patients admitted with ST-segment elevation myocardial infarction (STEMI).</p> <p>Methods</p> <p>The atherothrombotic samples were collected from a consecutive cohort consisting of 20 individuals admitted with STEMI to Stavanger University Hospital, Norway, from 2005-2006, presenting angiographically with an acute thrombotic occlusion of a coronary artery characterized by TIMI flow 0. The atherothrombotic plaques were obtained by aspiration thrombectomy during percutaneous coronary intervention within 12 hours from the onset of symptoms and prepared for IHC analysis.</p> <p>Results</p> <p>In the IHC analysis staining for PAPP-A occurred in the extracellular matrix of the plaques and no evidence of staining for PAPP-A was found in the thrombi.</p> <p>Conclusion</p> <p>Our results indicate that in vivo PAPP-A is strongly expressed in atherothrombotic plaques harvested from patients admitted with STEMI, as documented by IHC.</p> <p>Trial registration</p> <p><email>[email protected]</email></p

AGAP2-AS1 as a prognostic biomarker in low-risk clear cell renal cell carcinoma patients with progressing disease

Background Clear cell renal cell carcinoma (ccRCC) is the most common subtype of renal cancer and one of the most common cancers. While survival for localized ccRCC is good, the survival of metastatic disease is not, and thirty percent of patients with ccRCC develop metastases during follow-up. Although current scoring methods accurately identify patients at low progression risk, a small subgroup of those patients still experience metastasis. We therefore aimed to identify ccRCC progression biomarkers in "low-risk" patients who were potentially eligible for adjuvant treatments or more intensive follow-up. Methods We assembled a cohort of ccRCC patients (n = 443) and identified all "low-risk" patients who later developed progressing tumors (n = 8). Subsequently, we performed genome-wide expression profiling from formalin-fixed samples obtained at initial surgery from these "low-risk" patients and 16 matched patients not progressing to recurrence with metastasis. The patients were matched for Leibovich sore, creatinine, age, sex, tumor size and tumor stage. Key results were confirmed with qPCR and external data from The Cancer Genome Atlas. Results Principal component analysis indicated that systematic transcriptomic differences were already detectable at the time of initial surgery. One thousand one hundred sixty-seven genes, mainly associated with cancer and immune-related pathways, were differentially expressed between progressors and nonprogressors. A search for a classifier revealed that overexpression of AGAP2-AS1, an antisense long noncoding RNA, correctly classified 23 of 24 samples, years (4.5 years average) in advance of the discovery of metastasis and without requiring larger gene panels. Subsequently, we confirmed AGAP2-AS1 gene overexpression by qPCR in the same samples (p < 0.05). Additionally, in external data from The Cancer Genome Atlas, overexpression of AGAP2-AS1 is correlated with overall unfavorable survival outcome in ccRCC, irrespective of other prognostic predictors (p = 2.44E-7). Conclusion AGAP2-AS1 may represent a novel biomarker identifying high-risk ccRCC patients currently classified as "low risk" at the time of surgery.Peer reviewe

A multiomics disease progression signature of low‑risk ccRCC

Clear cell renal cell carcinoma (ccRCC) is the most common renal cancer. Identification of ccRCC likely to progress, despite an apparent low risk at the time of surgery, represents a key clinical issue. From a cohort of adult ccRCC patients (n = 443), we selected low-risk tumors progressing within a 5-years average follow-up (progressors: P, n = 8) and non-progressing (NP) tumors (n = 16). Transcriptome sequencing, miRNA sequencing and proteomics were performed on tissues obtained at surgery. We identified 151 proteins, 1167 mRNAs and 63 miRNAs differentially expressed in P compared to NP low-risk tumors. Pathway analysis demonstrated overrepresentation of proteins related to “LXR/ RXR and FXR/RXR Activation”, “Acute Phase Response Signaling” in NP compared to P samples. Integrating mRNA, miRNA and proteomic data, we developed a 10-component classifier including two proteins, three genes and five miRNAs, effectively differentiating P and NP ccRCC and capturing underlying biological differences, potentially useful to identify “low-risk” patients requiring closer surveillance and treatment adjustments. Key results were validated by immunohistochemistry, qPCR and data from publicly available databases. Our work suggests that LXR, FXR and macrophage activation pathways could be critically involved in the inhibition of the progression of low-risk ccRCC. Furthermore, a 10-component classifier could support an early identification of apparently low-risk ccRCC patients.Peer reviewe

Scoring system for renal pathology in Fabry disease: report of the International Study Group of Fabry Nephropathy (ISGFN)

Background. In Fabry nephropathy, alpha-galactosidase deficiency leads to accumulation of glycosphingolipids in all kidney cell types, proteinuria and progressive loss of kidney function. Methods. An international working group of nephrologists from 11 Fabry centres identified adult Fabry patients, and pathologists scored histologic changes on renal biopsies. A standardized scoring system was developed with a modified Delphi technique assessing 59 Fabry nephropathy cases. Each case was scored independently of clinical information by at least three pathologists with an average final score reported. Results. We assessed 35 males (mean age 36.4 years) and 24 females (43.9 years) who mostly had clinically mild Fabry nephropathy. The average serum creatinine was 1.3mg/dl (114.9 μmol/l); estimated glomerular filtration rate was 81.7 ml/min/1.73 m2 and urine protein to creatinine ratio was 1.08 g/g (122.0 mg/mmol). Males had greater podocyte vacuolization on light microscopy (mean score) and glycosphingolipid inclusions on semi-thin sections than females. Males also had significantly more proximal tubule, peritubular capillary and vascular intimal inclusions. Arteriolar hyalinosis was similar, but females had significantly more arterial hyalinosis. Chronic kidney disease stage correlated with arterial and glomerular sclerosis scores. Significant changes, including segmental and global sclerosis, and interstitial fibrosis were seen even in patients with stage 1-2 chronic kidney disease with minimal proteinuria. Conclusions. The development of a standardized scoring system of both disease-specific lesions, i.e. lipid deposition related, and general lesions of progression, i.e. fibrosis and sclerosis, showed a spectrum of histologic appearances even in early clinical stage of Fabry nephropathy. These findings support the role of kidney biopsy in the baseline evaluation of Fabry nephropathy, even with mild clinical disease. The scoring system will be useful for longitudinal assessment of prognosis and responses to therapy for Fabry nephropath