Abstract Background Clear cell renal cell carcinomas (ccRCC) frequently display a loss of function of the von Hippel–Lindau ( VHL ) gene. Objective To elucidate the putative relationship between VHL ...mutation status and immune checkpoint ligand programmed death-ligand 1 (PD-L1) expression. Design, setting, and participants A series of 32 renal tumors composed of 11 VHL tumor-associated and 21 sporadic RCCs were used to evaluate PD-L1 expression levels after sequencing of the three exons and exon–intron junctions of the VHL gene. The 786-O, A498, and RCC4 cell lines were used to investigate the mechanisms of PD-L1 regulation. Outcome measurements and statistical analysis Fisher's exact test was used for VHL mutation and Kruskal–Wallis test for PD-L1 expression. If no covariate accounted for the association of VHL and PD-L1, then a Kruskal–Wallis test was used; otherwise Cochran–Mantel–Haenzsel test was used. We also used the Fligner–Policello test to compare two medians when the distributions had different dispersions. Results and limitations We demonstrated that tumors from ccRCC patients with VHL biallelic inactivation (ie, loss of function) display a significant increase in PD-L1 expression compared with ccRCC tumors carrying one VHL wild-type allele. Using the inducible VHL 786-O-derived cell lines with varying hypoxia-inducible factor-2 alpha (HIF-2α) stabilization levels, we showed that PD-L1 expression levels positively correlate with VHL mutation and HIF-2α expression. Targeting HIF-2α decreased PD-L1, while HIF-2α overexpression increased PD-L1 mRNA and protein levels in ccRCC cells. Interestingly, chromatin immunoprecipitation and luciferase assays revealed a direct binding of HIF-2α to a transcriptionally active hypoxia-response element in the human PD-L1 proximal promoter in 786-O cells. Conclusions Our work provides the first evidence that VHL mutations positively correlate with PD-L1 expression in ccRCC and may influence the response to ccRCC anti-PD-L1/PD-1 immunotherapy. Patient summary We investigated the relationship between von Hippel–Lindau mutations and programmed death-ligand 1 expression. We demonstrated that von Hippel–Lindau mutation status significantly correlated with programmed death-ligand 1 expression in clear cell renal cell carcinomas.
Clear cell renal cell carcinomas (RCC) frequently display inactivation of von Hippel-Lindau (VHL) gene leading to increased level of hypoxia-inducible factors (HIF). In this study, we investigated ...the potential role of HIF2α in regulating RCC susceptibility to natural killer (NK) cell-mediated killing. We demonstrated that the RCC cell line 786-0 with mutated VHL was resistant to NK-mediated lysis as compared with the VHL-corrected cell line (WT7). This resistance was found to require HIF2α stabilization. On the basis of global gene expression profiling and chromatin immunoprecipitation assay, we found ITPR1 (inositol 1,4,5-trisphosphate receptor, type 1) as a direct novel target of HIF2α and that targeting ITPR1 significantly increased susceptibility of 786-0 cells to NK-mediated lysis. Mechanistically, HIF2α in 786-0 cells lead to overexpression of ITPR1, which subsequently regulated the NK-mediated killing through the activation of autophagy in target cells by NK-derived signal. Interestingly, both ITPR1 and Beclin-1 silencing in 786-0 cells inhibited NK-induced autophagy and subsequently increased granzyme B activity in target cells. Finally, in vivo ITPR1 targeting significantly enhanced the NK-mediated tumor regression. Our data provide insight into the link between HIF2α, the ITPR1-related pathway, and natural immunity and strongly suggest a role for the HIF2α/ITPR1 axis in regulating RCC cell survival.
Chronic kidney disease (CKD), secondary to renal fibrogenesis, is a public health burden. The activation of interstitial myofibroblasts and excessive production of extracellular matrix (ECM) proteins ...are major events leading to end-stage kidney disease. Recently, interleukin-15 (IL-15) has been implicated in fibrosis protection in several organs, with little evidence in the kidney. Since endogenous IL-15 expression decreased in nephrectomized human allografts evolving toward fibrosis and kidneys in the unilateral ureteral obstruction (UUO) model, we explored IL-15's renoprotective role by pharmologically delivering IL-15 coupled or not with its soluble receptor IL-15Rα. Despite the lack of effects on myofibroblast accumulation, both IL-15 treatments prevented tubulointerstitial fibrosis (TIF) in UUO as characterized by reduced collagen and fibronectin deposition. Moreover, IL-15 treatments inhibited collagen and fibronectin secretion by transforming growth factor-β (TGF-β)-treated primary myofibroblast cultures, demonstrating that the antifibrotic effect of IL-15 in UUO acts, in part, through a direct inhibition of ECM synthesis by myofibroblasts. In addition, IL-15 treatments resulted in decreased expression of monocyte chemoattractant protein 1 (MCP-1) and subsequent macrophage infiltration in UUO. Taken together, our study highlights a major role of IL-15 on myofibroblasts and macrophages, two main effector cells in renal fibrosis, demonstrating that IL-15 may represent a new therapeutic option for CKD.
Early interstitial fibrosis (IF) correlates with long-term renal graft dysfunction, highlighting the need for accurate quantification of IF. However, the currently used Banff classification exhibits ...some limitations. The aim of our study was to precisely describe the progression of IF after renal transplantation using a new morphometric image analysis method relying of Sirius Red staining. The morphometric analysis we developed showed high inter-observer and intra-observer reproducibility, with ICC 95% IC of respectively 0.75 0.67-0.81 (n = 151) and 0.88 0.72-0.95 (n = 21). We used this method to assess IF (mIF) during the first year after the kidney transplantation from 66 uncontrolled donors after circulatory death (uDCD). Both mIF and interstitial fibrosis (ci) according to the Banff classification significantly increased the first three months after transplantation. From M3 to M12, mIF significantly increased whereas Banff classification failed to highlight increase of ci. Moreover, mIF at M12 (p = 0.005) correlated with mean time to graft function recovery and was significantly associated with increase of creatininemia at M12 and at last follow-up. To conclude, the new morphometric image analysis method we developed, using a routine and cheap staining, may provide valuable tool to assess IF and thus to evaluate new sources of grafts.
Our aim in the study described here was to prospectively establish the feasibility of using and reproducibility of testicular shear-wave elastography in the assessment of testicular stiffness in 62 ...normal patients and 539 infertile men with obstructive azoospermia (OA), non-Klinefelter syndrome non-obstructive azoospermia (non-KS NOA), Klinefelter syndrome NOA (KS NOA), oligoasthenoteratozoospermia (OAT) or a left varicocele. The feasibility rate was 96.9%, with an intra-class correlation coefficient of 0.85 (95% confidence interval: 0.83-0.88). Median stiffness (interquartile range) values were 2.4 kPa (2.0, 2.9), 2.1 kPa (1.8, 2.5), 2.4 kPa (2.0, 2.7), 2.0 kPa (1.7, 2.4), 2.6 kPa (2, 3.2) and 2.2 kPa (1.8, 2.6) for men with a normal testis (n = 108), OAT (n = 689), OA (n = 119), non-KS NOA (n = 183), KS NOA (n = 70) and varicocele (n = 132), respectively. Testicular shear wave elastography is a feasible and reproducible technique. A significant positive association was found between stiffness and testis volume (p = 0.001). Testicular stiffness was higher in OA than in non-KS NOA populations (p = 1.e-10) and in KS NOA than in NOA populations (p = 2.0e-8), but the substantial number of overlapping values limited the clinical impact.
Background
Ultrasound elastography has been suggested for assessing organ fibrosis.
Objective
To study the feasibility of shear-wave elastography in children with kidney disease and the correlation ...between elasticity and kidney fibrosis in order to reduce the indications for kidney biopsy and its complications.
Materials and methods
Four operators measured kidney elasticity in children with kidney diseases or transplants, all of whom also had a renal biopsy. We assessed the feasibility and the intraobserver variability of the elasticity measurements for each probe used and each kidney explored. Then we tested the correlation between elasticity measurements and the presence of fibrosis.
Results
Overall, we analyzed 95 children and adolescents, 31 of whom had renal transplant. Measurements with the convex probe were possible in 100% of cases. Linear probe analysis was only possible for 20% of native kidneys and 50% of transplants. Intraobserver variabilities ranged from moderate to high, depending on the probe and kidney studied. Elasticity was higher with the linear probe than with the convex probe (
P
<0.001 for left kidney and
P
=0.03 for right kidney). Measurements did not differ from one kidney to another in the same child. Elasticity and fibrosis were both higher in transplant patients (
P
=0.02 with convex probe;
P
=0.01 with linear probe;
P
=0.04 overall). There was no correlation between elasticity and fibrosis.
Conclusion
Of the devices used in this work, kidney elastography was more accurately analyzed with a convex probe. Our study did not identify any correlation between elasticity and kidney fibrosis.
Recent treatment developments for metastatic renal cell carcinoma offer combinations of immunotherapies or immunotherapy associated with tyrosine kinase inhibitors (TKI). There is currently no ...argument to choose one solution or another. Easy-to-use markers to assess longitudinal responses to TKI are necessary to determine when to switch to immunotherapies. These new markers will enable an earlier adaptation of therapeutic strategy in order to prevent tumor development, unnecessary toxicity and financial costs. This study evaluates the potential of ultrasound molecular imaging to track the response to sunitinib in a clear cell renal carcinoma model (ccRCC). We used a patient-derived xenograft model for this imaging study. Mice harboring human ccRCC were randomized for sunitinib treatment vs. control. The tumors were imaged at days 0, 7, 14 and 28 with ultrasound molecular imaging. Signal enhancement was quantified and compared between the two groups after injections of non-targeted microbubbles and microbubbles targeting VEGFR1 and FSHR. The tumor growth of the sunitinib group was significantly slower. There was a significantly lower expression of both VEGFR-1 and FSHR molecular ultrasound imaging signals in the sunitinib group at all times of treatment (Days 7, 14 and 28). These results confirm the study hypothesis. There was no significant difference between the 2 groups for the non-targeted microbubble ultrasound signal. This study demonstrated for the first time the potential of VEGFR1 and FSHR, by ultrasound-based molecular imaging, to follow-up the longitudinal response to sunitinib in ccRCC. These results should trigger developments for clinical applications.
Hereditary cancers with cancer-predisposing mutations represent unique models of human oncogenesis, as a driving oncogenic event is present in germline. Currently, there are no satisfactory models to ...study these malignancies. We report the generation of IPSC from the somatic cells of a patient with hereditary c-
mutated papillary renal cell carcinoma (PRCC). From these cells we have generated spontaneous aggregates organizing in structures which expressed kidney markers such as PODXL and Six2. These structures expressed PRCC markers both in vitro and in vivo in NSG mice. Gene-expression profiling showed striking molecular similarities with signatures found in a large cohort of PRCC tumor samples. This analysis, applied to primary cancers with and without c-
mutation, showed overexpression of the BHLHE40 and KDM4C only in the c-
-mutated PRCC tumors, as predicted by c-
-mutated embryoid bodies transcriptome. These data therefore represent the first proof of concept of "hereditary renal cancer in a dish" model using c-
-mutated iPSC-derived embryoid bodies, opening new perspectives for discovery of novel predictive progression markers and for drug-screening for future precision-medicine strategies.
Lymphomas localized in the kidney are a rare entity that may be challenging to diagnose. We analyzed data from 10 patients with renal involvement of lymphoma diagnosed between 2009 and 2019 on fine ...needle biopsy from our tertiary center, and compared these with findings of 160 cases reported in the literature. Diffuse large B-cell lymphoma was the main histology subtype (40 and 38% in our sample and in the literature, respectively), followed by low-grade B-cell lymphomas, mostly from the marginal zone (MZ). Altogether, 106 patients had urological inaugural symptoms and 64 had general symptoms. Patients with urological presentation more often had renal masses than diffuse infiltration (
p
< 0.001), unilateral tumors (
p
= 0.0036) and low-grade B-cell lymphomas (17 vs 6%,
p
= 0.043). In both groups, nearly one-fourth of patients had diffuse (stage IV) lymphomas. Overall survival did not differ by the presence of urological/systemic symptoms, stage or aggressive lymphoma status. Notably, 3 of 10 patients from our series had MZ lymphomas associated with primary Sjögren syndrome revealed by acute kidney injury, including one where the autoimmune disease was detected. Lymphoproliferative disorders localized in the kidney are a challenging condition that can lead to detection of aggressive or diffuse lymphomas.
Objective
To assess PD-L1 expression in tumor (TC) and tumor infiltrating immune cells (IC) as a predictive factor of BCG therapy failure in high-risk NMIBC.
Materials and methods
Patients treated ...with complete resection followed by bladder BCG instillation for high-risk NMIBC were included. Early recurrence (ER) was defined as tumor recurrence after BCG induction course. The association between ER and immuno-histochemistry PD-L1
(E1L3N clone)
expression by tumors cells (TC) and tumor infiltrating immune cells (IC) was investigated using an exact Fisher test variant.
Results
A total of 186 patients were included, of whom 38 (20.4%) were ER, 35 (18.8%) were positive for TC PD-L1 expression and 60 (32.3%) were positive for IC PD-L1. ER was not significantly (
p
= 0.97) more frequent in the TC PD-L1 ≥ 1% group (
n
= 7, 20.0%) than in the TC PD-L1-negative group (
n
= 31, 20.5%). Patients with IC PD-L1 negative had ER in 15 (19.2%) cases and patients with IC PD-L1 ≥ 1% had ER in 23 (21.3%) cases. PD-L1-positive expression for IC (threshold > 1%) was correlated with immune infiltrate density (95.2% dense immune infiltrate vs 47.2% low immune infiltrate,
p
< 0.05), with increased expression of PD-L1 by IC after BCG therapy (
p
= 0.006).
Conclusion
No association was observed between immuno-histochemistry PD-L1 positivity and ER after BCG therapy. Nevertheless, the relationship between immune infiltrate and PD-L1 positivity confirmed the interest of assessing the immune infiltrate density to define tumor’s profile.
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