Screening of potential hub genes involved in Kidney Wilms tumor via bioinformatics analysis and experimental validation.

BACKGROUND: Wilms tumor (WT) is the most common pediatric embryonal tumor. Improving patient outcomes requires advances in understanding and targeting the multiple genes and cellular control pathways, but its pathogenesis is currently not well-researched. We aimed to identify the potential molecular biological mechanism of WT and develop new prognostic markers and molecular targets by comparing gene expression profiles of Wilms tumors and fetal normal kidneys. METHODS: Differential gene expression analysis was performed on Wilms tumor transcriptomic data from the GEO and TARGET databases. For biological functional analysis, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment were utilized. Out of 24 hub genes identified, nine were found to be prognostic-related through univariate Cox regression analysis. These nine genes underwent LASSO regression analysis to enhance the predictive capability of the model. The key hub genes were validated in the GSE73209 datasets, and cell function experiments were conducted to identify the genes' functions in WiT-49 cells. RESULTS: The enrichment analysis revealed that DEGs were significantly involved in the regulation of angiogenesis and regulation of cell differentiation. 24 DEGs were identified through PPI networks and the MCODE algorithm, and 9 of 24 genes were related to WT patients' prognosis. EMCN and CCNA1 were identified as key hub genes, and related to the progression of WT. Functionally, over-expression of EMCN and CCNA1 knockdown inhibited cell viability, proliferation, migration, and invasion of Wilms tumor cells. CONCLUSIONS: EMCN and CCNA1 were identified as key prognostic markers in Wilms tumor, suggesting their potential as therapeutic targets. Differential gene expression and enrichment analyses indicate significant roles in angiogenesis and cell differentiation.

LMO family gene polymorphisms and Wilms tumor susceptibility in Chinese children: a five-center case-control study.

BACKGROUND: Wilms tumor is the most prevalent embryonal kidney malignancy in children worldwide. Previous genome-wide association study (GWAS) identified that LIM domain only 1 (LMO1) gene polymorphisms affected the susceptibility to develop certain tumor types. Apart from LMO1, the LMO gene family members also include LMO2-4, each of which has oncogenic potential. METHODS: We conducted this five-center case‒control study to assess the correlations between single nucleotide polymorphisms in LMO family genes and Wilms tumor susceptibility. Odds ratios and 95% confidence intervals were calculated to evaluate the strength of the association. RESULTS: We found LMO1 rs2168101 G > T and rs11603024 C > T as well as LMO2 rs7933499 G > A were significantly associated with Wilms tumor risk. Stratified analysis demonstrated a protective role of rs2168101 GT/TT genotypes against Wilms tumor in the subgroups of age ≤ 18 months, males and clinical stages I/II compared to the rs2168101 GG genotype. Nevertheless, carriers with the rs11603024 TT genotype were more likely to have an increased risk of Wilms tumor than those with rs11603024 CC/CT genotypes in age > 18 months. And the rs11603024 was identified as a protective polymorphism for reducing the risk of Wilms tumor in the sex- and gender- subgroup. Likewise, carriers with the rs7933499 GA/AA genotypes were at significantly elevated risk of Wilms tumor in age ≤ 18 months and clinical stages I/II. CONCLUSION: Overall, our study identified the importance of LMO family gene polymorphisms on Wilms tumor susceptibility in Chinese children. Further investigations are needed to validate our conclusions.

[Identification of key genes in Wilms tumor based on high-throughput RNA sequencing and their impacts on prognosis and immune responses].

OBJECTIVE: To identify the key genes differentially expressed in Wilms tumor and analyze their potential impacts on prognosis and immune responses of the patients. METHODS: High-throughput RNA sequencing was used to identify the differentially expressed mRNAs in clinical samples of Wilms tumor and paired normal tissues, and their biological functions were analyzed using GO, KEGG and GSEA enrichment analyses. The hub genes were identified using STRING database, based on which a prognostic model was constructed using LASSO regression. The mutations of the key hub genes were analyzed and their impacts on immunotherapy efficacy was predicted using the cBioPortal platform. RT-qPCR was used to verify the differential expressions of the key hub genes in Wilms tumor. RESULTS: Of the 1612 differentially expressed genes identified in Wilms tumor, 1030 were up-regulated and 582 were down-regulated, involving mainly cell cycle processes and immune responses. Ten hub genes were identified, among which 4 genes (TP53, MED1, CCNB1 and EGF) were closely related to the survival of children with Wilms tumor. A 3-gene prognostic signature was constructed through LASSO regression analysis, and the patients stratified into with high- and low-risk groups based on this signature had significantly different survival outcomes (HR=1.814, log-rank P=0.002). The AUCs of the 3-, 5- and 7-year survival ROC curves of this model were all greater than 0.7. The overall mutations in the key hub genes or the individual mutations in TP53/CCNB1 were strongly correlated with a lower survival rates, and a high TP53 expression was correlated with a poor immunotherapy efficacy. RT-qPCR confirmed that the key hub genes had significant differential expressions in Wilms tumor tissues and cells. CONCLUSION: TP53 gene plays an important role in the Wilms tumor and may potentially serve as a new immunotherapeutic biomarker as well as a therapeutic target.

Targeting TRIP13 in favorable histology Wilms tumor with nuclear export inhibitors synergizes with doxorubicin.

Wilms tumor (WT) is the most common renal malignancy of childhood. Despite improvements in the overall survival, relapse occurs in ~15% of patients with favorable histology WT (FHWT). Half of these patients will succumb to their disease. Identifying novel targeted therapies remains challenging in part due to the lack of faithful preclinical in vitro models. Here we establish twelve patient-derived WT cell lines and demonstrate that these models faithfully recapitulate WT biology using genomic and transcriptomic techniques. We then perform loss-of-function screens to identify the nuclear export gene, XPO1, as a vulnerability. We find that the FDA approved XPO1 inhibitor, KPT-330, suppresses TRIP13 expression, which is required for survival. We further identify synergy between KPT-330 and doxorubicin, a chemotherapy used in high-risk FHWT. Taken together, we identify XPO1 inhibition with KPT-330 as a potential therapeutic option to treat FHWTs and in combination with doxorubicin, leads to durable remissions in vivo.

Effect of miR-590-3p/DKK1 Axis on the Progression of Wilms' Tumour.

BACKGROUND: Wilms' tumour is the most prevalent abdominal malignancy in children. This study focused on the mechanism of the miR-590-3p/Dickkopf 1 (DKK1) axis in Wilms' tumour. METHODS: The mRNA levels of miR-590-3p and DKK1 in 49 pairs of Wilms' tumour pathological specimens and normal tissues were determined using real-time quantitative polymerase chain reaction (RT-qPCR). Wilms' tumour cells' invasion ability and proliferative ability were assessed using a Transwell assay and Cell Counting Kit-8 (CCK-8) assay, respectively. Dual-luciferase assay was performed to evaluate the potential relationship between miR-590-3p and DKK1 in Wilms tumour. Furthermore, a mouse transplanted tumour model was constructed to explore the function of miR-590-3p inhibitor on Wilms' tumour growth in vivo. RESULTS: DKK1 emerged as a target gene of miR-590-3p in Wilms' tumour. DKK1 expression was downregulated (p < 0.01), but miR-590-3p was overexpressed (p < 0.01) in Wilms' tumour tissues compared to normal tissues. miR-590-3p overexpression accelerated Wilms' tumour invasive ability and cell proliferation (p < 0.01). Additionally, DKK1 partially reversed miR-590-3p-induced proliferation (p < 0.05) and invasion ability (p < 0.01). Furthermore, downregulation of miR-590-3p restrained the growth rate of transplanted tumours in nude mice (p < 0.01). CONCLUSIONS: Through the regulation of DKK1, miR-590-3p accelerated the invasion and proliferation of Wilms' tumour. The study suggests that the miR-590-3p/DKK1 axis represents a novel mechanism in Wilms' tumour.

A novel pyroptosis-related gene signature exhibits distinct immune cells infiltration landscape in Wilms' tumor.

BACKGROUND: Wilms' tumor (WT) is the most common renal tumor in childhood. Pyroptosis, a type of inflammation-characterized and immune-related programmed cell death, has been extensively studied in multiple tumors. In the current study, we aim to construct a pyroptosis-related gene signature for predicting the prognosis of Wilms' tumor. METHODS: We acquired RNA-seq data from TARGET kidney tumor projects for constructing a gene signature, and snRNA-seq data from GEO database for validating signature-constructing genes. Pyroptosis-related genes (PRGs) were collected from three online databases. We constructed the gene signature by Lasso Cox regression and then established a nomogram. Underlying mechanisms by which gene signature is related to overall survival states of patients were explored by immune cell infiltration analysis, differential expression analysis, and functional enrichment analysis. RESULTS: A pyroptosis-related gene signature was constructed with 14 PRGs, which has a moderate to high predicting capacity with 1-, 3-, and 5-year area under the curve (AUC) values of 0.78, 0.80, and 0.83, respectively. A prognosis-predicting nomogram was established by gender, stage, and risk score. Tumor-infiltrating immune cells were quantified by seven algorithms, and the expression of CD8( +) T cells, B cells, Th2 cells, dendritic cells, and type 2 macrophages are positively or negatively correlated with risk score. Two single nuclear RNA-seq samples of different histology were harnessed for validation. The distribution of signature genes was identified in various cell types. CONCLUSIONS: We have established a pyroptosis-related 14-gene signature in WT. Moreover, the inherent roles of immune cells (CD8( +) T cells, B cells, Th2 cells, dendritic cells, and type 2 macrophages), functions of differentially expressed genes (tissue/organ development and intercellular communication), and status of signaling pathways (proteoglycans in cancer, signaling pathways regulating pluripotent of stem cells, and Wnt signaling pathway) have been elucidated, which might be employed as therapeutic targets in the future.

Characterization of Alternative Splicing in High-Risk Wilms' Tumors.

The significant heterogeneity of Wilms' tumors between different patients is thought to arise from genetic and epigenetic distortions that occur during various stages of fetal kidney development in a way that is poorly understood. To address this, we characterized the heterogeneity of alternative mRNA splicing in Wilms' tumors using a publicly available RNAseq dataset of high-risk Wilms' tumors and normal kidney samples. Through Pareto task inference and cell deconvolution, we found that the tumors and normal kidney samples are organized according to progressive stages of kidney development within a triangle-shaped region in latent space, whose vertices, or "archetypes", resemble the cap mesenchyme, the nephrogenic stroma, and epithelial tubular structures of the fetal kidney. We identified a set of genes that are alternatively spliced between tumors located in different regions of latent space and found that many of these genes are associated with the epithelial-to-mesenchymal transition (EMT) and muscle development. Using motif enrichment analysis, we identified putative splicing regulators, some of which are associated with kidney development. Our findings provide new insights into the etiology of Wilms' tumors and suggest that specific splicing mechanisms in early stages of development may contribute to tumor development in different patients.

[Correlation of 1p/16q loss of heterozygosity and 1p gain with clinicopathological characteristics and prognosis in Wilms tumor].

Objective: To investigate the relationship between 1p/16q loss of heterozygosity (LOH) and 1p gain in Wilms tumor and their clinicopathologic characteristics and prognosis. Methods: A total of 175 Wilms tumor samples received from the Department of Pathology, Beijing Children's Hospital from September 2019 to August 2022 were retrospectively analyzed. The histopathologic type and presence of lymph node involvement were evaluated by two pathologists. The clinical data including patients'gender, age, tumor location, preoperative chemotherapy, and tumor stage were summarized. Fluorescence in situ hybridization (FISH) was done to detect 1p/16q LOH and 1p gain and their correlation with the clinicopathological features and prognosis were analyzed. Results: Among the 175 samples, 86 cases (49.1%) were male and 89 (50.9%) were female. The mean age was (3.5±2.9) years, and the median age was 2.6 years. There were 26 (14.9%) cases with 1p LOH, 28 (16.0%) cases with 16q LOH, 10 (5.7%) cases of LOH at both 1p and 16q, and 53 (30.3%) cases with 1q gain. 1q gain was significantly associated with 1p LOH (P<0.01) and 16q LOH (P<0.01). There were significant differences (P<0.01) between 1q gain, 1p LOH and 16q LOH among different age groups. The rate of 16q LOH in the high-risk histopathological subtype (50.0%) was significantly higher than that in the intermediate-risk subtype (13.6%, P<0.05). The frequency of 1q gain, 1p LOH, and 16q LOH in children with advanced clinical stages (Ⅲ and Ⅳ) was significantly higher than that in children with early clinical stages (Ⅰ and Ⅱ). 1q gain, 1p LOH, and 16q LOH showed no significant correlation with gender, unilateral or bilateral disease, chemotherapy, or lymph node metastasis. The progression-free survival (PFS) time for patients with 1q gain and 1p LOH was significantly shorter than those without these aberrations (P<0.05). Additionally, the PFS time of patients with 16q LOH was slightly shorter than those with normal 16q, although the difference was not statistically significant. Patients with stage Ⅲ to Ⅳ disease exhibiting 1q gain or 1p LOH had a significantly higher relative risk of recurrence, metastasis, and mortality. Conclusions: 1p/16q LOH and 1q gain are associated with age, high-risk histological type, and clinical stage in Wilms tumor. 1q gain and 1p LOH are significantly correlated with the prognosis of Wilms tumor.

Declined circular RNA mitofusin 2 constrains the deterioration of Wilms tumor via modulating microRNA-372-3p/transforming growth factor-ß receptor type 2 axis.

To explore the action and mechanism in which circular RNA (circRNA) mitofusin 2 (MFN2) repressed the malignant proliferation of Wilms tumor (WT) via modulating microRNA (miR)-372-3p/transforming growth factor-ß receptor type 2 (TGFBR2) axis. CircRNA MFN2 was distinctly elevated in the tissues and cells of WT patients, while miR-372-3p was silenced in the tissues and cells of WT. Test of TGFBR2, PCNA and Bax was implemented. Transfection with si-circRNA MFN2 or miR-372-3p-mimic restrained cancer cell advancement and the number of PCNA content was declined, while transfection with miR-372-3p-inhibitor was opposite, and PCNA content was augmented. MiR-372-3p-inhibitor turned around si-circRNA MFN2's therapeutic action after co-transfection with si-circRNA MFN2 + miR-372-3p-inhibitor. Ultimately, it was verified that circRNA MFN2 was negatively associated with miR-372-3p, which was negatively linked with TGFBR2, and circRNA MFN2 was positively associated with TGFBR2. To sum up, the results of this research illuminated circRNA MFN2 repressed WT's malignant proliferation via modulating miR-372-3p/TGFBR2 axis.

Overexpression of aquaporin-1 plays a vital role in proliferation, apoptosis, and pyroptosis of Wilms' tumor cells.

BACKGROUND: Nephroblastoma, also known as Wilms' tumor (WT), is an embryonic malignant tumor and one of the most common malignant tumors in the abdominal region of children. The exact role and underlying mechanisms of aquaporin-1 (AQP1) in the occurrence and development of nephroblastoma remain unclear. METHODS: After overexpression of AQP1, cell proliferation was assessed using the CCK-8 proliferation assay and EdU staining. Flow cytometry was employed to assess cell apoptosis, and Western blotting (WB) analysis was conducted to validate the expression of relevant protein markers. mRNA sequencing (mRNA-Seq) was performed on WT cells overexpressing AQP1 to predict and characterize the associated mechanisms. Transmission electron microscopy was utilized to observe changes in the ultrastructure of WT cells undergoing apoptosis and pyroptosis following AQP1 overexpression. Functional in vivo validation was conducted through animal experiments. RESULTS: We validated that overexpression of AQP1 inhibited cell proliferation and promoted cell apoptosis and pyroptosis both in vitro and in vivo. mRNA-Seq analysis of WT cells with AQP1 overexpression suggested that these effects might be mediated through the inhibition of the JAK-STAT signaling pathway. Additionally, we discovered that overexpression of AQP1 activated the classical pyroptosis signaling pathway dependent on caspase-1, thereby promoting pyroptosis in WT. CONCLUSION: These findings highlight the important functional role of AQP1 in the pathobiology of nephroblastoma, providing novel insights into the development of this disease. Moreover, these results offer new perspectives on the potential therapeutic targeting of AQP1 as a treatment strategy for nephroblastoma.

Mechanism of LncRNA FTX regulates nephroblastoma progression through MiR-215-5p/PI3K/AKT axis.

BACKGROUND: Nephroblastoma, also more commonly known as Wilms tumor (WT), is a common childhood malignancy that connects tumorigenesis and organ development in the kidney. OBJECTIVE: The current study focused on the effect of lncRNA FTX in nephroblastoma. STUDY DESIGN: Expression of lncRNA FTX in nephroblastoma tissues and cells was determined. The expression location of lncRNA FTX was detected by FISH. The binding of lncRNA FTX and miR-215-5p with Ago2 was verified by RIP. Following gain- and loss-of-function approaches, the crucial role of lncRNA FTX and miR-215-5p in nephroblastoma cell functions was measured with the involvement of the PI3K/AKT pathway. RESULTS: LncRNA FTX was elevated and miR-215-5p was declined in nephroblastoma. Silencing of lncRNA FTX or mimic of miR-215-5p inhibited the malignant properties of nephroblastoma cells. LncRNA FTX was localized in the cytoplasm and might bind miR-215-5p. LncRNA FTX promoted the malignant features of nephroblastoma cells by inhibiting miR-215-5p through activating of the PI3K/AKT pathway. CONCLUSIONS: LncRNA FTX is capable of accelerating nephroblastoma development in vitro by reducing miR-215-5p through activating of the PI3K/AKT pathway, indicating LncRNA FTX may possibly a future target for the diagnosis and treatment of nephroblastoma. SUMMARY FIGURE.

Exosomal long non-coding RNA MALAT1: a candidate of liquid biopsy in monitoring of Wilms' tumor.

PURPOSE: Wilms' tumor (WT) is a rare kidney cancer that primarily affects children. Exosomes are extracellular vesicles that cargo nucleic acids, proteins,etc. for cellular communication. Long non-coding RNAs (lncRNAs) have utility as biomarkers for cancer diagnosis, prognosis, and disease monitoring. We hypothesize that expression of lncRNA, metastasis-associated lung adenocarcinoma transcript-1(MALAT1), is dysregulated and possibly trafficked within exosomes to influence the tissue microenvironment for metastasis and recurrence of WT. METHODS: We investigated the expression of MALAT1 in thirty WT samples by qPCR. Exosomes were isolated using a precipitated and affinity-binding-based kit, and characterized using TEM, NTA, and DLS. RESULTS: Mean number of exosomes was 9.01×108/mL in primary culture, 1.64×108/mL in urine, and 4.65×108/plasma:400µl. Average yield of total RNA was 1.28µg (primary-culture supernatant:1ml), 1.47µg (Urine:1ml), 1.65µg (Plasma:400 µL). We quantified MALAT1 in exosomes derived from these sources in patients of WT. Expression of MALAT1 was significantly downregulated (p=0.008) in WT samples. CONCLUSION: This is the first study that demonstrated the presence of lncRNA MALAT1 in various invasive and non-invasive samples of patients with WT(primary tissue culture, urine, and plasma samples).

Bilateral Peters' anomaly, aniridia and Wilms tumour (WAGR syndrome) in monozygotic twins.

AIM: This study reports the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins subsequently diagnosed with Wilms tumour (WAGR syndrome). METHODS: Two monozygotic female twins were referred at age 2 months with bilateral corneal opacity. A diagnosis of Peters' anomaly associated to aniridia was made in both eyes of both twins. Physical examination and ultrasonography were carried out at 12 months of age to explore the possibility of WAGR-related anomalies, specifically Wilms tumour. DNA were isolated and subjected to whole exome sequencing. RESULTS: Peters' anomaly associated to aniridia in both eyes as well as bilateral Wilms tumour in both children were diagnosed. Exome analyses showed a large heterozygous deletion encompassing 6 648 473 bp in chromosome 11p13, using Integrative Genomics Viewer and AnnotSV software. CONCLUSION: WAGR syndrome is a rare contiguous gene deletion syndrome with a greater risk of developing Wilms tumour associated with Peters' anomaly and congenital aniridia. However, co-occurrence of both anomalies was rarely reported in twins, and never in both eyes of monozygotic twins. Here, we report the bilateral association of Peters' anomaly and congenital aniridia in monozygotic twins with WAGR syndrome.

Wilms tumour resulting from paternal transmission of a TRIM28 pathogenic variant-A first report.

Wilms tumour (nephroblastoma) is a renal embryonal tumour that is frequently caused by constitutional variants in a small range of cancer predisposition genes. TRIM28 has recently been identified as one such gene. Previously, observational data strongly suggested a parent of origin effect, whereby Wilms tumour only occurred following maternal inheritance of a pathogenic genetic variant. However, here we report a child with bilateral Wilms tumour who had inherited a pathogenic TRIM28 variant from their father. This finding suggests that genetic counselling for paternally inherited pathogenic variants in TRIM28 should include discussion of a potential risk of Wilms tumour.

Multidimensional Transcriptomics Unveils RNF34 as a Prognostic Biomarker and Potential Indicator of Chemotherapy Sensitivity in Wilms' Tumour.

Nephroblastoma, colloquially known as Wilms' tumour (WT), is the predominant malignant renal neoplasm arising in the paediatric population. Modern therapeutic approaches for WT incorporate a synergistic combination of surgical intervention, radiotherapy, and chemotherapy, which substantially ameliorate the overall patient survival rate. Despite this, the optimal sequence of chemotherapy and surgical intervention remains a matter of contention, with each strategy presenting its own strengths and weaknesses that could influence clinical decision-making. To make some headway on this clinical dilemma, we deployed a multidimensional transcriptomics integration approach by analysing bulk RNA sequencing data with 136 samples, as well as single-nucleus RNA sequencing (snRNA-seq) and paired spatial transcriptome sequencing (stRNA) data from 32 WT specimens. Our findings identified a distinct elevation of RNF34 expression within WT samples, which correlated with unfavourable prognostic outcomes. Leveraging the Genomics of Drug Sensitivity in Cancer (GDSC), we simultaneously revealed that patients with high expression of RNF34 have higher sensitivity to commonly used chemotherapy drugs for WT. Furthermore, our analysis of snRNA and stRNA data unveiled a reduced proportion of RNF34 expression in neoplastic cells after chemotherapy. Moreover, stRNA data delineated a significant association between a higher proportion of RNF34 expression in cancer cells and adverse features such as anaplastic histology and tumour recurrence. Intriguingly, we also observed a close association between elevated RNF34 expression and a characteristic exhausted tumour immune microenvironment. Collectively, our findings underscore the pivotal role of RNF34 in the prognostic prediction potential and treatment sensitivity of WT. This comprehensive analysis can potentially inform and refine clinical decision-making for WT patients and guide future studies towards the development of optimized, rational therapeutic strategies.

Race and Ethnic Group Enrollment and Outcomes for Wilms Tumor: Analysis of the Current Era Children's Oncology Group Study, AREN03B2.

BACKGROUND: To review race and ethnic group enrollment and outcomes for Wilms tumor (WT) across all 4 risk-assigned therapeutic trials from the current era Children's Oncology Group Renal Tumor Biology and Risk Stratification Protocol, AREN03B2. STUDY DESIGN: For patients with WT enrolled in AREN03B2 (2006 to 2019), disease and biologic features, therapeutic study-specific enrollment, and event-free (EFS) and overall (OS) 4-year survival were compared between institutionally reported race and ethnic groups. RESULTS: Among 5,146 patients with WT, no statistically significant differences were detected between race and ethnic groups regarding subsequent risk-assigned therapeutic study enrollment, disease stage, histology, biologic factors, or overall EFS or OS, except the following variables: Black children were older and had larger tumors at enrollment, whereas Hispanic children had lower rates of diffuse anaplasia WT and loss of heterozygosity at 1p. The only significant difference in EFS or OS between race and ethnic groups was observed among the few children treated for diffuse anaplasia WT with regimen UH-1 and -2 on high-risk protocol, AREN0321. On this therapeutic arm only, Black children showed worse EFS (hazard ratio = 3.18) and OS (hazard ratio = 3.42). However, this finding was not replicated for patients treated with regimen UH-1 and -2 under AREN03B2 but not on AREN0321. CONCLUSIONS: Race and ethnic group enrollment appeared constant across AREN03B2 risk-assigned therapeutic trials. EFS and OS on these therapeutic trials when analyzed together were comparable regarding race and ethnicity. Black children may have experienced worse stage-specific survival when treated with regimen UH-1 and -2 on AREN0321, but this survival gap was not confirmed when analyzing additional high-risk AREN03B2 patients.

Differentiation Potential of Hypodifferentiated Subsets of Nephrogenic Rests and Its Relationship to Prognosis in Wilms Tumor.

Background Wilms tumor (WT) is highly curable, although anaplastic histology or relapse imparts a worse prognosis. Nephrogenic rests (NR) associated with a high risk of developing WT are abnormally retained embryonic kidney precursor cells. Methods After pseudo-time analysis using single-cell RNA sequencing (scRNA-seq) data, we generated and validated a WT differentiation-related gene (WTDRG) signature to predict overall survival (OS) in children with a poor OS. Results A differentiation trajectory from NR to WT was identified and showed that hypodifferentiated subsets of NR could differentiate into WT. Classification of WT children with anaplastic histology or relapse based on the expression patterns of WTDRGs suggested that patients with relatively high levels of hypodifferentiated NR presented a poorer prognosis. A WTDRG-based risk model and a clinically applicable nomogram was developed. Conclusions These findings may inform oncogenesis of WT and interventions directed toward poor prognosis in WT children of anaplastic histology or relapse.

Further evidence that the neurodevelopmental gene FBXW7 predisposes to Wilms tumor.

Somatic variants in the NOTCH pathway regulator FBXW7 are frequently seen in a variety of malignancies. Heterozygous loss-of-function germline variants in FBXW7 have recently been described as causative for a neurodevelopmental syndrome. Independently, FBXW7 was also considered as a susceptibility gene for Wilms tumor due to a few observations of heterozygous germline variants in patients with Wilms tumor. Whether the same FBXW7 variants are implicated in both, neurodevelopmental delay and Wilms tumor formation, remained unclear. By clinical testing, we now observed a patient with neurodevelopmental delay due to a de novo constitutional mosaic FBXW7 splice site pathogenic variant who developed Wilms tumor. In the tumor, we identified a second hit frameshift variant in FBXW7. Immunohistochemical staining was consistent with mosaic loss of FBXW7 protein expression in the tumor. Our data support the role of constitutional FBXW7 pathogenic variants in both, neurodevelopmental disorder and the etiology of Wilms tumor. Therefore, Wilms tumor screening should be considered in individuals with constitutional or germline pathogenic variants in FBXW7 and associated neurodevelopmental syndrome.

Prophylactic bilateral nephrectomy and preemptive kidney transplantation for Denys-Drash syndrome prior to development of kidney failure.

BACKGROUND  : Nephropathy in Denys-Drash syndrome (DDS) develops within a few months of birth, often progressing to kidney failure. Wilms tumors also develop at an early age with a high rate of incidence. When a patient does not have Wilms tumor but develops kidney failure, prophylactic bilateral nephrectomy, and kidney transplantation (KTX) is an optimal approach owing to the high risk of Wilms tumor development. In the case presented here, prophylactic bilateral nephrectomy and KTX were performed in a patient who had not developed Wilms tumor or kidney failure. However, the treatment option is controversial as it involves the removal of a tumor-free kidney and performing KTX in the absence of kidney failure. CASE DIAGNOSIS/TREATMENT: We present the case of a 7-year-old boy, born at 38 weeks gestation. Examinations at the age of 1 year revealed severe proteinuria and abnormal internal and external genitalia. Genetic testing identified a missense mutation in exon 9 of the WT1 gene, leading to the diagnosis of DDS. At the age of 6 years, he had not yet developed Wilms tumor and had grown to a size that allowed him to safely undergo a KTX. His kidney function was slowly deteriorating (chronic kidney disease (CKD) stage 3), but he had not yet developed kidney failure. Two treatment options were considered for this patient: observation until the development of kidney failure or prophylactic bilateral nephrectomy with KTX to avoid Wilms tumor development. After a detailed explanation of options to the patient and family, they decided to proceed with prophylactic bilateral nephrectomy and KTX. At the latest follow-up 4 months after KTX, the patient's kidney functioned well without proteinuria. CONCLUSION: We performed prophylactic bilateral nephrectomy with KTX on a DDS patient who had not developed kidney failure or Wilms tumor by the age of 7 years. Although the risk of development of Wilms tumor in such a patient is unclear, this treatment may be an optimal approach for patients who are physically able to undergo KTX, considering the potentially lethal nature of Wilms tumor in CKD patients.

Teratoma-associated and so-called pure Wilms tumour of the ovary represent two separate tumour types with distinct molecular features.

AIMS: Ovarian Wilms tumour (WT)/nephroblastoma is an extremely rare neoplasm that has been reported to occur in pure form or as a component of a teratomatous neoplasm. We hypothesized that teratoma-associated and pure ovarian WT may represent different tumour types with diverging molecular backgrounds. To test this hypothesis, we comprehensively characterized a series of five tumours originally diagnosed as ovarian WT. METHODS AND RESULTS: The five cases comprised three teratoma-associated (two mature and one immature) and two pure WTs. Two of the teratoma-associated WTs consisted of small nodular arrangements of "glandular"/epithelial structures, while the third consisted of both an epithelial and a diffuse spindle cell/blastemal component. The pure WTs consisted of "glandular" structures, which were positive for sex cord markers (including inhibin and SF1) together with a rhabdomyosarcomatous component. The two pure WTs harboured DICER1 pathogenic variants (PVs), while the three associated with teratomas were DICER1 wildtype. Panel-based DNA sequencing of four of the cases did not identify PVs in the other genes investigated. Analysis of the HA19/IGF2 imprinting region showed retention of imprinting in the pure WTs but loss of heterozygosity with hypomethylation of the ICR1 region in two of three teratoma-associated WTs. Furthermore, copy number variation and clustering-based whole-genome DNA methylation analyses identified divergent molecular profiles for pure and teratoma-associated WTs. CONCLUSION: Based on the morphological features, immunophenotype, and molecular findings (DICER1 PVs, copy number, and DNA methylation profiles), we suggest that the two cases diagnosed as pure primary ovarian WT represent moderately to poorly differentiated Sertoli Leydig cell tumours (SLCTs), while the tumours arising in teratomas represent true WTs. It is possible that at least some prior cases reported as pure primary ovarian WT represent SLCTs.