Lung tumors with distinct p53 mutations respond similarly to p53 targeted therapy but exhibit genotype-specific statin sensitivity.

Lung adenocarcinoma accounts for ∼40% of lung cancers, the leading cause of cancer-related death worldwide, and current therapies provide only limited survival benefit. Approximately half of lung adenocarcinomas harbor mutations in TP53 (p53), making these mutants appealing targets for lung cancer therapy. As mutant p53 remains untargetable, mutant p53-dependent phenotypes represent alternative targeting opportunities, but the prevalence and therapeutic relevance of such effects (gain of function and dominant-negative activity) in lung adenocarcinoma are unclear. Through transcriptional and functional analysis of murine KrasG12D -p53null , -p53R172H (conformational), and -p53R270H (contact) mutant lung tumors, we identified genotype-independent and genotype-dependent therapeutic sensitivities. Unexpectedly, we found that wild-type p53 exerts a dominant tumor-suppressive effect on mutant tumors, as all genotypes were similarly sensitive to its restoration in vivo. These data show that the potential of p53 targeted therapies is comparable across all p53-deficient genotypes and may explain the high incidence of p53 loss of heterozygosity in mutant tumors. In contrast, mutant p53 gain of function and their associated vulnerabilities can vary according to mutation type. Notably, we identified a p53R270H -specific sensitivity to simvastatin in lung tumors, and the transcriptional signature that underlies this sensitivity was also present in human lung tumors, indicating that this therapeutic approach may be clinically relevant.

Predictors of renal and patient outcomes in anti-GBM disease: clinicopathologic analysis of a two-centre cohort.

BACKGROUND: Patients with anti-glomerular basement membrane (GBM) disease are at increased risk of morbidity and mortality from renal failure, pulmonary haemorrhage or complications of treatment. One-third also have circulating anti-neutrophil cytoplasmic antibodies (ANCA). The aim of this study was to determine the clinicopathologic predictors of patient and renal outcomes in anti-GBM disease with or without ANCA. METHODS: Retrospective review of 43 patients diagnosed with anti-GBM disease over 20 years in two centres, including nine with dual anti-GBM and ANCA positivity. Renal biopsies from 27 patients were scored for the presence of active and chronic lesions. RESULTS: Dual-positive patients were almost 20 years older than those with anti-GBM positivity alone (P = 0.003). The overall 1-year patient and renal survivals were 88 and 16%, respectively. Oligoanuria at diagnosis was the strongest predictor of mortality; none of the 16 patients without oligoanuria died. In a Cox regression model excluding oligoanuria, age was the only other independent predictor of survival. Pulmonary haemorrhage and dialysis dependence did not influence mortality. Thirty-five of the forty-three (81%) patients required dialysis at presentation, including all nine dual-positive patients. Of them, only two (5.7%) regained renal function at 1 year. By logistic regression, oligoanuria at diagnosis and percentage of crescents were independent predictors of dialysis independence at 3 months. However, in biopsied patients, the presence of crescents (>75%) added little to the presence of oligoanuria in predicting dialysis independence. Histological activity and chronicity indices did not predict renal outcome. Two of the nine (22%) dual-positive patients relapsed compared with none of the anti-GBM alone patients. Seven patients received kidney transplants without disease recurrence. CONCLUSIONS: Oligoanuria is the strongest predictor of patient and renal survival while percentage of glomerular crescents is the only pathologic parameter associated with poor renal outcome in anti-GBM disease. Kidney biopsy may not be necessary in oligoanuric patients without pulmonary haemorrhage.

Versatile and enhanced tumour modelling in mice via somatic cell transduction.

Genetically engineered mouse (GEM) models of cancer currently comprise the most accurate way to experimentally recapitulate the human disease in the laboratory. Given recent advances in genomics and genetic screens, however, as well as an increasing urgency for the translation of effective preclinical treatments into the clinic, there is a pressing need to make these models easier and more efficient to work with. Accordingly, we have developed a versatile lentivirus-based approach to induce tumours from somatic cells of GEMs, add or subtract gene expression and render the tumours imageable from a simple breeding stock. The vectors deliver a tamoxifen-inducible and self-inactivating Cre recombinase, conditional bioluminescent and fluorescent proteins and an shRNA component. Following the transduction of somatic cells, tumours are initiated by Cre-mediated recombination of the inherited floxed alleles. Self-inactivation of Cre expression switches on the expression of luciferase, thereby rendering the recombined cells and resulting tumours bioluminescent. We demonstrate proof of concept of this approach by inducing bioluminescent lung tumours in conditional Kras and p53 mice. We also show that a variant vector expressing shRNA alters tumour growth dynamics and the histological grade associated with the inherited genotype. This approach comprises a versatile means to induce imageable and spontaneous tumour burden in mice. The vectors can be readily customized at the bench to modify reporter readout or tumour phenotype without additional transgenic strain development or breeding. They should also be useful for inducing imageable tumours in organs other than the lung, provided that the inherited conditional genotype is sufficiently penetrant.

ANCA serotype and histopathological classification for the prediction of renal outcome in ANCA-associated glomerulonephritis.

BACKGROUND: The phenotype of renal involvement in anti-neutrophil cytoplasmic antibodies (ANCA) vasculitis has a major influence on survival, and histological subgrouping of diagnostic renal biopsies has been proposed to aid in the prediction of renal outcome. We aimed to validate this histological subgrouping and to investigate the additional value of ANCA serotype in the prediction of renal outcome. METHODS: Data were retrospectively collected from the time of diagnosis by systematic review of medical records from 136 patients with renal biopsies recruited to cohorts from the UK and Spain, over 15 years. The end point, renal survival, was the composite of end-stage renal disease (ESRD) or death from any cause. The occurrence of ESRD, Stage 4 Kidney Disease Outcomes Quality Initiative-Chronic Kidney Disease, was assessed separately, in order to establish a severity index risk of chronic kidney disease. RESULTS: Renal survival at 5 years was 96% in the focal, 86% in the crescentic, 81% in the mixed and 61% in the sclerotic subgroups (P = 0.03). Myeloperoxidase (MPO)-ANCA was associated with more severe disease when compared with PR3-ANCA, as demonstrated by a lower frequency of focal and higher frequency of sclerotic subgroups, by more advanced interstitial fibrotic change and by lower glomerular filtration rate at diagnosis and worse renal function at 1 and 2 years. CONCLUSIONS: We have confirmed the predictive value for renal survival of the ANCA vasculitis histology classification in a multi-centre study. We found a worse renal outcome in patients with tubulointerstitial fibrosis and atrophy. MPO-ANCA positive patients had a worse renal prognosis due to more severe glomerular injury. These results contribute to patient stratification in renal vasculitis for therapeutic, epidemiological and basic research.

What nephrologists need to know about antiphospholipid syndrome.

Antiphospholipid syndrome (APS) is an autoimmune disorder characterized by recurrent arterial or venous thrombosis and/or pregnancy losses, in the presence of persistently elevated levels of anticardiolipin antibodies (aCL) and/or evidence of circulating lupus anticoagulant (LA). The kidney is a major target organ in both primary and secondary APS. With the expanding spectrum of renal diseases associated with APS, and the impact of APS in ESRD care, this subject is of increasing relevance to nephrologists. This review describes the various clinical manifestations and histological features of this syndrome, with reference to the kidney.

Educational case: a patient with proteinuria.

This is an educational case suitable for all readers, but aimed particularly at trainees preparing for MRCP. Using the example of a patient presenting to clinic with proteinuria, aspects of differential diagnosis, pathology and management are explored.

Acute kidney injury as the presenting complaint of ceftazidime-induced immune-mediated haemolysis.

We present the case of ceftazidime-induced immune-mediated haemolysis with associated acute kidney injury in a 43-year-old woman. The patient initially presented to the regional cystic fibrosis centre for treatment of an infective exacerbation of cystic fibrosis. After initiation of ceftazidime (a third-generation cephalosporin), renal function rapidly deteriorated and a fall in haemoglobin was noted. On transfer to our care, a haemolysis screen identified immune-mediated haemolysis, and renal biopsy confirmed the finding of acute tubular necrosis secondary to haem pigment. The patient's renal function deteriorated such that she required haemodialysis, although she subsequently recovered and is now dialysis-independent. Although acute haemolytic reactions are recognised with third-generation cephalosporins, this is the first reported case of ceftazidime-induced immune-mediated haemolysis with acute kidney injury. Given the increased frequency of cephalosporin usage, it is important for both nephrologists and general physicians to be aware of this rare but very serious complication.

Predicting Outcome in Patients with Anti-GBM Glomerulonephritis.

BACKGROUND AND OBJECTIVES: Large studies on long-term kidney outcome in patients with anti-glomerular basement membrane (anti-GBM) GN are lacking. This study aimed to identify clinical and histopathologic parameters that predict kidney outcome in these patients. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This retrospective analysis included a total of 123 patients with anti-GBM GN between 1986 and 2015 from six centers worldwide. Their kidney biopsy samples were classified according to the histopathologic classification for ANCA-associated GN. Clinical data such as details of treatment were retrieved from clinical records. The primary outcome parameter was the occurrence of ESRD. Kidney survival was analyzed using the log-rank test and Cox regression analyses. RESULTS: The 5-year kidney survival rate was 34%, with an improved rate observed among patients diagnosed after 2007 (P=0.01). In patients with anti-GBM GN, histopathologic class and kidney survival were associated (P<0.001). Only one of 15 patients with a focal class biopsy sample (≥50% normal glomeruli) developed ESRD. Patients with a sclerotic class biopsy sample (≥50% globally sclerotic glomeruli) and patients with 100% cellular crescents did not recover from dialysis dependency at presentation. In multivariable analysis, dialysis dependency at presentation (hazard ratio [HR], 3.17; 95% confidence interval [95% CI], 1.59 to 6.32), percentage of normal glomeruli (HR, 0.97; 95% CI, 0.95 to 0.99), and extent of interstitial infiltrate (HR, 2.02; 95% CI, 1.17 to 3.50) were predictors of ESRD during follow-up. CONCLUSIONS: Dialysis dependency, low percentage of normal glomeruli, and large extent of interstitial infiltrate are associated with poor kidney outcome in anti-GBM GN. Kidney outcome has improved during recent years; the success rate doubled after 2007. PODCAST: This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2017_11_21_CJASNPodcast_18_1_v.mp3.

Sirolimus-induced pulmonary hypersensitivity associated with a CD4 T-cell infiltrate.

The differential diagnosis of pulmonary infiltrates after solid-organ transplantation presents a broad differential diagnosis including opportunistic infections and drug-induced lung disease. We report an adult liver transplant recipient who had breathlessness and pulmonary infiltrates following the introduction of sirolimus, and in whom transbronchial biopsy demonstrated a granulomatous interstitial pneumonitis and an organizing pneumonia with a CD4 T-cell infiltrate suggesting a T-helper cell-associated reaction to a processed sirolimus protein complex. Withdrawal of sirolimus produced a rapid clinical and radiologic improvement. This case indicates that with the increasing use of sirolimus, clinicians need to be aware of pulmonary hypersensitivity from this agent.

Sirolimus-induced pneumonitis following liver transplantation.

Sirolimus-induced pneumonitis has emerged as a potentially serious complication in renal transplantation but only single case reports of this condition have been described after liver transplantation (LT), where experience with sirolimus is relatively limited. We report our experience, the largest to date, of sirolimus-induced pneumonitis following LT. Between 1999 and 2006, 186 liver transplant patients received sirolimus-based immunosuppression, after initial therapy with calcineurin inhibitors (CNIs). All cases of sirolimus-induced pneumonitis were recorded and a retrospective review of the case notes of such patients was undertaken for the purpose of this analysis. Of 186 liver transplant patients receiving sirolimus, 4 (2.2%) developed pneumonitis that was attributed to the drug; the time from starting sirolimus to presentation was varied (1.5-30 months). The most common presenting symptoms were dyspnea, cough and fatigue. The median sirolimus level at the time of diagnosis was 9.7 ng/mL (range, 7-19.5 ng/mL). All patients in the series underwent thoracic computed tomography, which showed similar changes in all patients, and lung biopsy, which revealed features consistent with a drug-induced pneumonitis. In all 4 patients, sirolimus-induced pneumonitis resolved following cessation of therapy but took weeks to months for complete recovery. In conclusion, sirolimus-induced pneumonitis occurred in at least 2% of liver transplant recipients and should be suspected in patients who develop respiratory symptoms while on sirolimus. Although it may be life threatening, early recognition and cessation of sirolimus can lead to complete resolution of pneumonitis.

Giant atypical ossifying fibromyxoid tumour of the calf.

We present a case of giant atypical ossifying fibromyxoid tumour (OFMT) of soft tissue, occurring in the calf, in a 77-year-old woman. The patient presented with a history of bleeding ulcer over a calf lump that had been present for over 4 years. Clinical presentation, radiological features and histopathologic findings are described, and the relevant literature is reviewed.