Francesco Trevisani

Common noncoding UMOD gene variants induce salt-sensitive hypertension and kidney damage by increasing uromodulin expression

Hypertension and chronic kidney disease (CKD) are complex traits representing major global health problems. Multiple genome-wide association studies have identified common variants in the promoter of the UMOD gene, which encodes uromodulin, the major protein secreted in normal urine, that cause independent susceptibility to CKD and hypertension. Despite compelling genetic evidence for the association between UMOD risk variants and disease susceptibility in the general population, the underlying biological mechanism is not understood. Here, we demonstrate that UMOD risk variants increased UMOD expression in vitro and in vivo. Uromodulin overexpression in transgenic mice led to salt-sensitive hypertension and to the presence of age-dependent renal lesions similar to those observed in elderly individuals homozygous for UMOD promoter risk variants. The link between uromodulin and hypertension is due to activation of the renal sodium cotransporter NKCC2. We demonstrated the relevance of this mechanism in humans by showing that pharmacological inhibition of NKCC2 was more effective in lowering blood pressure in hypertensive patients who are homozygous for UMOD promoter risk variants than in other hypertensive patients. Our findings link genetic susceptibility to hypertension and CKD to the level of uromodulin expression and uromodulins effect on salt reabsorption in the kidney. These findings point to uromodulin as a therapeutic target for lowering blood pressure and preserving renal function.

End-Stage Renal Disease After Renal Surgery in Patients with Normal Preoperative Kidney Function: Balancing Surgical Strategy and Individual Disorders at Baseline

Although nephron-sparing surgery (NSS) has demonstrated benefit in terms of renal function preservation, it is unclear whether NSS might also decrease the risk of end-stage renal disease (ESRD) relative to radical nephrectomy (RN). In the current paper, we aimed to report the rate and the predictors of ESRD after surgery, accounting for detailed individual baseline characteristics and comorbidities. A multi-institutional collaboration among five European tertiary care centers allowed study of 2027 patients with normal preoperative renal function and a clinically localized T1abN0M0 renal mass. Cox regression analyses were used to predict the risk of ESRD (defined as the onset of a postoperative estimated glomerular filtration rate <15ml/min per 1.73 m2) after adjusting for the individual baseline risk of developing chronic kidney disease. Univariable ESRD rates at 5 and 10 yr of follow-up were virtually equivalent for patients who underwent NSS (1.5% and 2.5%, respectively) versus RN (1.9% and 2.7%, respectively; hazard ratio [HR]: 0.8; 95% confidence interval [CI], 0.4-1.6). However, diabetes, smoking, uncontrolled hypertension, and other comorbidities were consistently more frequent in the NSS group relative to their RN counterparts. After adjusting for detailed baseline individual characteristics, NSS was shown to have an independent protective effect relative to RN (HR: 0.4; 95% CI, 0.2-0.8; p=0.02) at multivariable analyses. PATIENT SUMMARY After accounting for individual baseline characteristics, such as age, diabetes, uncontrolled hypertension, or other comorbidities, partial nephrectomy independently protects against end-stage renal disease and the consequent need for dialysis relative to radical nephrectomy.

MicroRNA 193b-3p as a predictive biomarker of chronic kidney disease in patients undergoing radical nephrectomy for renal cell carcinoma

Background:A significant proportion of patients undergoing radical nephrectomy (RN) for clear-cell renal cell carcinoma (RCC) develop chronic kidney disease (CKD) within a few years following surgery. Chronic kidney disease has important health, social and economic impact and no predictive biomarkers are currently available. MicroRNAs (miRs) are small non-coding RNAs implicated in several pathological processes.Methods:Primary objective of our study was to define miRs whose deregulation is predictive of CKD in patients treated with RN. Ribonucleic acid from formalin-fixed paraffin embedded renal parenchyma (cortex and medulla isolated separately) situated >3 cm from the matching RCC was tested for miR expression using nCounter NanoString technology in 71 consecutive patients treated with RN for RCC. Validation was performed by RT–PCR and in situ hybridisation. End point was post-RN CKD measured 12 months post-operatively. Multivariable logistic regression and decision curve analysis were used to test the statistical and clinical impact of predictors of CKD.Results:The overexpression of miR-193b-3p was associated with high risk of developing CKD in patients undergoing RN for RCC and emerged as an independent predictor of CKD. The addition of miR-193b-3p to a predictive model based on clinical variables (including sex and estimated glomerular filtration rate) increased the sensitivity of the predictive model from 81 to 88%. In situ hybridisation showed that miR-193b-3p overexpression was associated with tubule-interstitial inflammation and fibrosis in patients with no clinical or biochemical evidence of pre-RN nephropathy.Conclusions:miR-193b-3p might represent a useful biomarker to tailor and implement surveillance strategies for patients at high risk of developing CKD following RN.

Characterisation of the immune-related transcriptome in resected biliary tract cancers

Although biliary tract cancers (BTCs) are known to have an inflammatory component, a detailed characterisation of immune-related transcripts has never been performed. In these studies, nCounter PanCancer Immune Profiling Panel was used to assess the expression of 770 immune-related transcripts in the tumour tissues (TTs) and matched adjacent tissues (ATs) of resected BTCs. Cox regression analysis and Kaplan–Meier methods were used to correlate findings with relapse-free survival (RFS). The first analysis in the TT and AT of an exploratory set (n = 22) showed deregulation of 39 transcripts associated with T-cell activation. Risk of recurrence was associated with a greater number of genes deregulated in AT in comparison to TT. Analysis in the whole set (n = 53) showed a correlation between AT cytotoxic T-lymphocyte antigen-4 (CTLA4) expression and RFS, which maintained statistical significance at multivariate analysis. CTLA4 expression correlated with forkhead box P3 (FOXP3) expression, suggesting enrichment in T regulatory cells. CTLA4 is known to act by binding to the cluster of differentiation 80 (CD80). No association was seen between AT CD80 expression and RFS. However, CD80 expression differentiated prognosis in patients who received adjuvant chemotherapy. We showed that the immunomodulatory transcriptome is deregulated in resected BTCs. Our study includes a small number of patients and does not enable to draw definitive conclusions; however, it provides useful insights into potential transcripts that may deserve further investigation in larger cohorts of patients. Transcript Profiling Nanostring data have been submitted to GEO repository: GSE90698 and GSE90699.

Carbon dating cancer: defining the chronology of metastatic progression in colorectal cancer.

Background Patients often ask oncologists how long a cancer has been present before causing symptoms or spreading to other organs. The evolutionary trajectory of cancers can be defined using phylogenetic approaches but lack of chronological references makes dating the exact onset of tumours very challenging. Patients and methods Here, we describe the case of a colorectal cancer (CRC) patient presenting with synchronous lung metastasis and metachronous thyroid, chest wall and urinary tract metastases over the course of 5 years. The chest wall metastasis was caused by needle tract seeding, implying a known time of onset. Using whole genome sequencing data from primary and metastatic sites we inferred the complete chronology of the cancer by exploiting the time of needle tract seeding as an in vivo ‘stopwatch’. This approach allowed us to follow the progression of the disease back in time, dating each ancestral node of the phylogenetic tree in the past history of the tumour. We used a Bayesian phylogenomic approach, which accounts for possible dynamic changes in mutational rate, to reconstruct the phylogenetic tree and effectively ‘carbon date’ the malignant progression. Results The primary colon cancer emerged between 5 and 8 years before the clinical diagnosis. The primary tumour metastasized to the lung and the thyroid within a year from its onset. The thyroid lesion presented as a tumour-to-tumour deposit within a benign Hurthle adenoma. Despite rapid metastatic progression from the primary tumour, the patient showed an indolent disease course. Primary cancer and metastases were microsatellite stable and displayed low chromosomal instability. Neo-antigen analysis suggested minimal immunogenicity. Conclusion Our data provide the first in vivo experimental evidence documenting the timing of metastatic progression in CRC and suggest that genomic instability might be more important than the metastatic potential of the primary cancer in dictating CRC fate.

New developments in the treatment of chemotherapy-induced neutropenia: focus on balugrastim

Neutropenia and febrile neutropenia are two major complications of chemotherapy. Dose reductions, delays in treatment administration, and the use of granulocyte colony-stimulating factors are equally recommended options to preserve absolute neutrophil count in case of chemotherapy regimens bringing a risk of febrile neutropenia of 20% or higher. Recombinant granulocyte colony-stimulating factors, such as filgrastim and lenograstim, have a short elimination half-life (t1/2) and need to be used daily, while others, like pegfilgrastim and lipegfilgrastim, are characterized by a long t1/2 requiring only a single administration per cycle. Balugrastim is a novel long-acting recombinant granulocyte colony-stimulating factor obtained by means of a genetic fusion between recombinant human serum albumin and granulocyte colony-stimulating factor. Albumin binding increases the molecular weight and determines a high plasmatic stability leading to a t1/2 of ~19 days. Balugrastim’s efficacy, safety, and tolerability have been assessed in four different clinical trials involving breast cancer patients treated with doxorubicin and docetaxel. Pegfilgrastim was chosen as a comparator. Balugrastim was noninferior to pegfilgrastim with regard to the reduction of mean duration of severe neutropenia during cycle 1. Moreover, both treatments were comparable in terms of efficacy and safety profile. Balugrastim was well tolerated, with the only related adverse event being mild to moderate bone pain. The aim of this review is to summarize the currently available literature data on balugrastim.

Longitudinal Liquid Biopsy and Mathematical Modeling of Clonal Evolution Forecast Time to Treatment Failure in the PROSPECT-C Phase II Colorectal Cancer Clinical Trial

Sequential profiling of plasma cell-free DNA (cfDNA) holds immense promise for early detection of patient progression. However, how to exploit the predictive power of cfDNA as a liquid biopsy in the clinic remains unclear. RAS pathway aberrations can be tracked in cfDNA to monitor resistance to anti-EGFR monoclonal antibodies in patients with metastatic colorectal cancer. In this prospective phase II clinical trial of single-agent cetuximab in RAS wild-type patients, we combine genomic profiling of serial cfDNA and matched sequential tissue biopsies with imaging and mathematical modeling of cancer evolution. We show that a significant proportion of patients defined as RAS wild-type based on diagnostic tissue analysis harbor aberrations in the RAS pathway in pretreatment cfDNA and, in fact, do not benefit from EGFR inhibition. We demonstrate that primary and acquired resistance to cetuximab are often of polyclonal nature, and these dynamics can be observed in tissue and plasma. Furthermore, evolutionary modeling combined with frequent serial sampling of cfDNA allows prediction of the expected time to treatment failure in individual patients. This study demonstrates how integrating frequently sampled longitudinal liquid biopsies with a mathematical framework of tumor evolution allows individualized quantitative forecasting of progression, providing novel opportunities for adaptive personalized therapies.Significance: Liquid biopsies capture spatial and temporal heterogeneity underpinning resistance to anti-EGFR monoclonal antibodies in colorectal cancer. Dense serial sampling is needed to predict the time to treatment failure and generate a window of opportunity for intervention. Cancer Discov; 8(10); 1270-85. ©2018 AACR. See related commentary by Siravegna and Corcoran, p. 1213 This article is highlighted in the In This Issue feature, p. 1195.

MicroRNAs as mediators of resistance mechanisms to small-molecule tyrosine kinase inhibitors in solid tumours.

Receptor tyrosine kinases (RTKs) are widely expressed transmembrane proteins that act as receptors for growth factors and other extracellular signalling molecules. Upon ligand binding, RTKs activate intracellular signalling cascades, and as such are involved in a broad variety of cellular functions including differentiation, proliferation, migration, invasion, angiogenesis, and survival under physiological as well as pathological conditions. Aberrant RTK activation can lead to benign proliferative conditions as well as to various forms of cancer. Indeed, more than 70% of the known oncogene and proto-oncogene transcripts involved in cancer code for RTKs. Consequently, these receptors are broadly studied as targets in the treatment of different tumours, and a large variety of small-molecule tyrosine kinase inhibitors (TKIs) are approved for therapy. In most cases, patients develop resistance to the TKIs within a short time. MicroRNAs are short (18–22 nucleotides) non-protein-coding RNAs that fine-tune cell homeostasis by controlling gene expression at the post-transcriptional level. Deregulation of microRNAs is common in many cancers, and increasing evidence exists for an important role of microRNAs in the development of resistance to therapies, including TKIs. In this review we focus on the role of microRNAs in mediating resistance to small-molecule TKIs in solid tumours.

The Effect of Anatomical Location of Lymph Node Metastases on Cancer Specific Survival in Patients with Clear Cell Renal Cell Carcinoma

Background Positive nodal status (pN1) is an independent predictor of survival in renal cell carcinoma (RCC) patients. However, no study to date has tested whether the location of lymph node (LN) metastases does affect oncologic outcomes in a population submitted to radical nephrectomy (RN) and extended lymph node dissection (eLND). Objective To describe nodal disease dissemination in clear cell RCC (ccRCC) patients and to assess the effect of the anatomical sites and the number of nodal areas affected on cancer specific mortality (CSM). Design, setting and partecipants The study included 415 patients who underwent RN and eLND, defined as the removal of hilar, side-specific (pre/paraaortic or pre/paracaval) and interaortocaval LNs for ccRCC, at two institutions. Outcome measurement and statistical analysis Descriptive statistics were used to depict nodal dissemination in pN1 patients, stratified according to nodal site and number of involved areas. Multivariable Cox regression analyses and Kaplan-Meier curves were used to explore the relationship between pN1 disease features and survival outcomes. Results and limitations Median number of removed LN was 14 (IQR 9–19); 23% of patients were pN1. Among patients with one involved nodal site, 54 and 26% of patients were positive only in side-specific and interaortocaval station, respectively. The most frequent nodal site was the interaortocaval and side-specific one, for right and left ccRCC, respectively. Interaortocaval nodal positivity (HR 2.3, CI 95%: 1.3–3.9, p < 0.01) represented an independent predictor of CSM. Conclusions When ccRCC patient harbour nodal disease, its spreading can occur at any nodal station without involving the others. The presence of interoartocaval positive nodes does affect oncologic outcomes. Patient summary Lymph node invasion in patients with clear cell renal cell carcinoma is not following a fixed anatomical pattern. An extended lymph node dissection, during treatment for primary kidney tumour, would aid patient risk stratification and multimodality upfront treatment.

When to Perform Preoperative Bone Scintigraphy for Kidney Cancer Staging: Indications for Preoperative Bone Scintigraphy

OBJECTIVE To identify an objective and reproducible strategy for preoperative staging bone scintigraphy (BS) in patients diagnosed with renal cell carcinoma (RCC), because in the absence of objective criteria, the decision to perform preoperative BS remains a subjective practice. PATIENTS AND METHODS The study included a total of 2008 patients with RCC treated with surgery and prospectively included into an institutional database. The study outcome was the presence of 1 or more bone lesions suspicious for metastases at staging BS. A multivariable logistic regression model predicting a positive BS was fitted. The predictors consisted of the preoperative clinical tumor (cT) and clinical nodal (cN) stages, the presence of systemic symptoms, and the platelet-to-hemoglobin (PLT/Hb) ratio. RESULTS The rate of positive BS was 4% (n = 81). At the multivariable logistic regression analysis, cT2, cN1, the presence of systemic symptoms, and the PLT/Hb ratio were all associated with am increased risk of positive BS (P <.05). Following the 2000-sample bootstrap validation, the concordance index was 0.77 (proposed model) vs 0.63 (decision making based on symptoms only). At the decision curve analysis, the proposed strategy was associated with a higher net benefit. If BS is performed when the risk of positive result is >5%, a negative BS is spared in 80% and a positive BS is missed in 2% of the population only. CONCLUSION Using preoperative variables, it is possible to accurately estimate the risk of positive BS at RCC staging using preoperative characteristics. Compared with the strategy supported by available guidelines, the proposed model was more objective, statistically more accurate, and clinically associated with higher net benefit.