Clear cell renal cell carcinoma (ccRCC) represents the most common type of kidney cancer with high mortality in its advanced stages. Our study aim was to explore the correlation between tumor epithelial-to-mesenchymal transition (EMT) and patient survival. Renal biopsies of tumorous and adjacent nontumorous tissue were taken with a 16 g needle from our patients (n = 26) undergoing partial or radical nephrectomy due to ccRCC RNA sequencing libraries were generated using Illumina TruSeq® Access library preparation protocol and TruSeq Small RNA library preparation kit. Next generation sequencing (NGS) was performed on Illumina HiSeq2500. Comparative analysis of matched sample pairs was done using the Bioconductor Limma/voom R-package. Liquid chromatography-tandem mass spectrometry and immunohistochemistry were applied to measure and visualize protein abundance. We detected an increased generic EMT transcript score in ccRCC Gene expression analysis showed augmented abundance of AXL and MMP14, as well as down-regulated expression of KL (klotho). Moreover, microRNA analyses demonstrated a positive expression correlation of miR-34a and its targets MMP14 and AXL Survival analysis based on a subset of genes from our list EMT-related genes in a publicly available dataset showed that the EMT genes correlated with ccRCC patient survival. Several of these genes also play a known role in fibrosis. Accordingly, recently published classifiers of solid organ fibrosis correctly identified EMT-affected tumor samples and were correlated with patient survival. EMT in ccRCC linked to fibrosis is associated with worse survival and may represent a target for novel therapeutic interventions.
The use of ultrasound and microbubble-enhanced drug delivery, commonly referred to as sonoporation, has reached numerous clinical trials and has shown favourable results. Nevertheless, the microbubbles and acoustic path also pass through healthy tissues. To date, the majority of studies have focused on the impact to diseased tissues and rarely evaluated the impact on healthy and collateral tissue. The aim of this study was to test the effect and feasibility of low-intensity sonoporation on healthy kidneys in a mouse model. In our work here, we used a clinical diagnostic ultrasound system (GE Vivid E9) with a C1-5 ultrasound transducer combined with a software modification for 20-µs-long pulses to induce the ultrasound-guided drug delivery of doxorubicin (DOX) in mice kidneys in combination with SonoVue® and Sonazoid™ microbubbles. The acoustic output settings were within the commonly used diagnostic ranges. Sonoporation with SonoVue® resulted in a significant decrease in weight vs. DOX alone (p = 0.0004) in the first nine days, whilst all other comparisons were not significant. Ultrasound alone resulted in a 381% increase in DOX uptake vs. DOX alone (p = 0.0004), whilst SonoVue® (p = 0.0001) and Sonazoid™ (p < 0.0001) further increased the uptake nine days after treatment (419% and 493%, respectively). No long-standing damage was observed in the kidneys via histology. In future sonoporation and drug uptake studies, we therefore suggest including an "ultrasound alone" group to verify the actual contribution of the individual components of the procedure on the drug uptake and to perform collateral damage studies to ensure there is no negative impact of low-intensity sonoporation on healthy tissues.
Abstract Renal fibrosis is a progressive histological manifestation leading to chronic kidney disease (CKD) and associated with mitochondrial dysfunction. In previous work, we showed that Bemcentinib, an Axl receptor tyrosine kinase inhibitor, reduced fibrosis development. In this study, to investigate its effects on mitochondrial dysfunction in renal fibrosis, we analysed genome‐wide transcriptomics data from a unilateral ureter obstruction (UUO) murine model in the presence or absence of bemcentinib (n = 6 per group) and SHAM‐operated (n = 4) mice. Kidney ligation resulted in dysregulation of mitochondria‐related pathways, with a significant reduction in the expression of oxidative phosphorylation (OXPHOS), fatty acid oxidation (FAO), citric acid cycle (TCA), response to reactive oxygen species and amino acid metabolism‐related genes. Bemcentinib treatment increased the expression of these genes. In contrast, AKT/PI3K signalling pathway genes were up‐regulated upon UUO, but bemcentinib largely inhibited their expression. At the functional level, ligation reduced mitochondrial biomass, which was increased upon bemcentinib treatment. Serum metabolomics analysis also showed a normalizing amino acid profile in UUO, compared with SHAM‐operated mice following bemcentinib treatment. Our data suggest that mitochondria and mitochondria‐related pathways are dramatically affected by UUO surgery and treatment with Axl‐inhibitor bemcentinib partially reverses these effects.
Abstract Background and Aims Interstitial fibrosis, characterised by the accumulation of extracellular matrix in the cortical interstitium, is directly correlated with progressive chronic kidney disease secondary to inflammatory, immunologic, obstructive or metabolic causes. An invariant histologic marker of this progression is the accumulation of fibroblasts, with the phenotypic appearance of activated myofibroblasts expressing alpha smooth muscle actin (αSMA) within intracellular contractile stress fibres. Once present, these myofibroblasts are prognostic indicators of expansion of fibrotic matrix and progressive tubular atrophy, leading towards end-stage disease. The Receptor Tyrosine Kinase AXL is involved in a range of kidney pathologies, with increased activity associated with Epithelial to Mesenchymal Transition (EMT) and tubular proliferation following podocyte loss. In mice treated with an angiotensin-converting enzyme (ACE) inhibitor, enhancement of AXL expression is localised to tubular segments within the medulla and there is evidence of parallel regulatory control of ACE and AXL. We have demonstrated enhanced expression of AXL and the mesenchymal marker, vimentin in diseased human kidney tissue secondary to diabetes or hypertension. Targeting AXL with a small-molecule inhibitor has previously been reported to attenuate fibrosis and reduce inflammation in the unilateral ureteric-outflow obstruction (UUO) model of kidney fibrosis in mice (Landolt et al., 2019). Tilvestamab is a novel function blocking humanized anti-AXL antibody. Tilvestamab blocks GAS6-mediated AXL receptor activation in fibroblasts and renal tubule epithelial cells and mediates AXL receptor internalization and degradation. In this study we aimed to further characterise AXL as a target in CKD and to investigate anti-fibrotic efficacy of tilvestamab. Method Eight weeks old male C57BL/6 mice underwent UUO operation. After 15 days, kidneys were dissociated and stained with a high dimensional single cell mass cytometry 33 markers antibody panel. Data were analysed using JMP Genomics (v.8.2). Precision Cut Kidney Slices (PCKSs) from explanted human kidney tissue were propagated in a bioreactor (Paish et al., 2019, FibroFind, UK). PCKS were incubated for 72hrs in the presence of investigational drugs. Secreted collagen1a1 were quantified by ELISA. RNA was reverse transcribed to cDNA and used in qPCRs to measure Col1a1 and αSMA. FFPE sections were stained for αSMA. High magnification images were taken of each slide and analysed for surface area covered by the stain. Results Expression pattern of AXL during development of kidney fibrosis in the UUO model was investigated using a mass cytometry antibody panel designed for identifying subpopulations of immune cells as well as cell populations of the fibrotic stroma. Two predominant cell populations were affected by ligation; the mesenchymal and the immune island. AXL was a marker characterising several of the key populations that expanded upon ligation supporting a role for AXL in kidney fibrosis pathogenesis. In an ex vivo model of human PCKS, tilvestamab dose-dependently reduced the levels of αSMA. When combined with the lower of two doses of the ACE inhibitor enalapril, the lowest dose of tilvestamab synergized to reduce αSMA levels further as well as reducing secreted Collagen 1a1. Conclusion AXL expression is induced in key cell populations during development of kidney fibrosis supporting AXL as a novel target in CKD. Tilvestamab represents a promising strategy for the pharmacologic intervention of kidney fibrosis, and the potential synergy with current reno-protective therapies warrants further exploration.
Next generation sequencing (NGS) and especially ribonucleic acid (RNA) sequencing is a powerful tool to acquire insights into molecular disease mechanisms. Therefore, it is of interest to optimize methods for RNA extraction from archival, formalin fixed and paraffin embedded (FFPE) tissues. This is challenging due to RNA degradation and chemical modifications. The aim of this study was to find the most appropriate method to extract RNA from FFPE renal tissue to enable NGS.We evaluated seven commercially available RNA extraction kits: High Pure FFPE RNA Isolation (Roche), ExpressArt Clear FFPE RNAready (Amsbio), miRNeasy FFPE, RNeasy FFPE (Qiagen), PureLink FFPE Total RNA (Invitrogen), RecoverAll Total Nucleic Acid Isolation (Ambion) and Absolutely RNA FFPE Kit (Agilent). RNA was obtained from tissue blocks of two healthy, male Wistar rats and from normal renal tissue of patients undergoing nephrectomy. Yield and quality of RNA extracted from rat whole kidney sections, human kidney core biopsies and laser capture microdissected (LCM) glomerular cross-sections were assessed: Analyses of RNA quantity were performed using NanoDrop and Qubit. RNA quality is reflected by DV200 values (% of RNA fragments >200 nucleotides) utilizing the Agilent 2100 BioAnalyzer. RNA of human LCM samples was subsequently sequenced using the Illumina TruSeq(®) RNA Access Library Preparation Kit.Total RNA can be extracted from archival renal biopsies in sufficient quality and quantity from one human kidney biopsy section and from around 100 LCM glomerular cross-sections to enable successful RNA library preparation and sequencing using commercially available RNA extraction kits.
Objective: Hypertensive nephropathy (HN) represents a major cause of chronic kidney disease, but it is incompletely understood why some patients show disease progression. Our project aim is to identify potential markers of disease progression and novel therapeutic targets. Design and method: Adult patients (n=43; n=16 females, mean age 53 years) with biopsy-verified HN were categorized as ’early’ (estimated glomerular filtration rate (eGFR) >45 ml/min/1.73m2) or ’late’ disease (eGFR <45 ml/min/1.73m2) at the time of biopsy. Patients were further divided into “stable” (eGFR decline <3 ml/min/year) or “progressive” (eGFR decline >3 ml/min/year or start of renal replacement therapy) after median follow-up of 10 years (5-22). TruSeq Exome sequencing was executed after RNA extraction (miRNeasy FFPE kit, Qiagen) at Novogene, Cambridge, UK. Quality control and data analysis was performed using R Studio (v4.2.0) and QIAGEN Ingenuity Pathway Analysis. Results: We analyzed the following subgroups of HN patients: early stable (ES, n=11), early progressive (EP, n=11), late stable (LS, n=9) and late progressive (LP, n=12). Differentially expressed genes (DEG, fold change (FC) >1.5 and p-value < 0.05) were identified, with n=265 in ES vs. EP, and n=674 in LS vs. LP. Principal component analysis (PCA) showed separation of ES vs. EP and LS vs. LP, as depicted in Figure 1A and B. K-nearest neighbour (KNN) analysis of DEG identified a 6-gene classifier in LS vs. LP (19/21 samples correctly classified), while IER5L and CNTNAP5 were the top 2-gene classifier in ES vs. EP (20/21 samples). These classifiers, as well as other DEGs such as PER1, YB1, TIMP3, ADAMTS4, IGFBP5 and EGF could represent novel targets to inhibit disease progression. Differentially regulated pathways were associated with regulation of TP53 activity and circadian rhythm involving melatonin metabolism in ES vs. EP, and metabolic processes related to water-soluble vitamins, glutathione and sphingolipids in LS vs. LP. Conclusions: Transcriptomic profiling from diagnostic kidney biopsies with HN can distinguish future disease progression from non-progression and may identify novel therapeutic targets.
Novel predictive tools for clear cell renal cell carcinoma (ccRCC) are urgently needed. MicroRNAs (miRNAs) have been increasingly investigated for their predictive value, and formalin-fixed paraffin-embedded biopsy archives may potentially be a valuable source of miRNA sequencing material, as they remain an underused resource. Core biopsies of both cancerous and adjacent normal tissues were obtained from patients (n = 12) undergoing nephrectomy. After small RNA-seq, several analyses were performed, including classifier evaluation, obesity-related inquiries, survival analysis using publicly available datasets, comparisons to the current literature and ingenuity pathway analyses. In a comparison of tumour vs. normal, 182 miRNAs were found with significant differential expression; miR-155 was of particular interest as it classified all ccRCC samples correctly and correlated well with tumour size (R² = 0.83); miR-155 also predicted poor survival with hazard ratios of 2.58 and 1.81 in two different TCGA (The Cancer Genome Atlas) datasets in a univariate model. However, in a multivariate Cox regression analysis including age, sex, cancer stage and histological grade, miR-155 was not a statistically significant survival predictor. In conclusion, formalin-fixed paraffin-embedded biopsy tissues are a viable source of miRNA-sequencing material. Our results further support a role for miR-155 as a promising cancer classifier and potentially as a therapeutic target in ccRCC that merits further investigation.
Rectus sheath hematoma (RSH) is a rare bleeding site which can be life-threatening. Our aim was to analyze clinical features, diagnosis, treatment and outcome of these cases in a general hospital. Results: During a period of 24 months, 8 cases of RSH were diagnosed (0.1% of all inpatients). Mean age was 79.4 years (y, SD +/- 14.1). 75% were female. 7 patients (pts) were on therapy with oral anticoagulants (OAC), 2 had a history of additional therapy with aspirin (ASA), 4 had low molecular weight heparin (LMWH) for bridging of OAC therapy. 4 pts had INR values between 3.1 - 4.4. One pt with liver cirrhosis (Child A), mild thrombocytopenia had ASA and LMWH prophylactically. Five pts (63%) were coughing. Main symptom was localized pain in 7 pts. One pt was incidentally diagnosed on a CT scan performed for different reason. 7 pts had a palpable mass of the abdominal wall. 5 RSH were diagnosed with CT, 2 with ultrasound, 1 clinically. All pts were treated conservatively. In 7 pts vitamine K and Beriplex® was substituted to reverse OAC. 4 pts received blood transfusions (1 - 4 units). The mean change of hemoglobin (Hb) was 37 g/l (SD +/- 22 g/l). The renal function was impaired in 7 pts (mean creatinine clearance 51 ml/min +/- 12.4) and declined further. 3 out of 8 pts died (38%, age 90 - 92 y, all female). In these patients, the observed change in Hb was 42 - 58 g/l. 2 pts had combination of VKA and LMWH. 1 pt had VKA only. Conclusion: Acute abdominal pain in pts with any form of OAC or therapy to inhibit platelet function should always raise suspicion about RSH. Extensive blood loss, shock and aggravation of renal failure can be fatal. In majority of cases, the hematoma is palpable and should prompt further examination of the abdominal wall. It is crucial to normalize coagulation parameters and to correct intravascular volume depletion to avoid shock and further decline of renal failure.
