Wilms tumor

Immune checkpoint markers and tumour mutation burden in Wilms tumour: a study of 59 cases

Wilms tumour (WT) is the most common renal tumour in children, and studies of immune checkpoint inhibitors (ICIs) treatment and markers are limited in number. In this study we investigated the ICIs' related immune landscape by examining the expression of PD-L1, PD-1, CD8 and DNA mismatch repair (MMR) proteins by immunohistochemistry (IHC), tumour mutation burden (TMB), and correlations with histology and clinical outcome. Positive PD-L1 (SP263) expression was defined as modified combined positive score (CPS) ≥1. A total of 59 WTs (from 2000 to 2017), including eight (14.0%) with anaplasia, from 46 patients were analysed (45 primary and 14 metastatic). Thirteen WTs (13/59, 22%) were positive for PD-L1 (8 primary, 5 metastatic; CPS 1.11-3.42). Positive PD-L1 expression was associated with diffuse anaplasia (p<0.05) and significantly shorter progression-free survival (p<0.05) among WTs with favourable histology (n=39). CD8+ lymphocytes were present in all analysed WTs. A subset of CD8+ cells co-expressed PD-1, which was associated with favourable histology and treatment. MMR IHC stains identified two (2/18, 11%) WTs with isolated PMS2 loss. All six WTs analysed for TMB showed low mutation burden. We found CD8+ lymphocytes in all analysed WTs and identified a fraction of WT (17.8% of primary and 35.8% of metastatic) with positive PD-L1 CPS, suggesting potential response to ICIs in some patients.

The synergistic effects of anoikis-related genes and EMT-related genes in the prognostic prediction of Wilms tumor

Wilms tumor (WT) is the most common type of malignant abdominal tumor in children; it exhibits a high degree of malignancy, grow rapidly, and is prone to metastasis. This study aimed to construct a prognosis model based on anoikis-related genes (ARGs) and epithelial-mesenchymal transition (EMT)-related genes (ERGs) for WT patients; we assessed the characteristics of the tumor microenvironment and treatment efficacy, as well as identifying potential therapeutic targets. To this end, we downloaded transcriptome sequencing data and clinical data for WT and normal renal cortices and used R to construct and validate the prognostic model based on ARGs and ERGs. Additionally, we performed clinical feature analysis, nomogram construction, mutation analysis, drug sensitivity analysis, Connectivity Map (cMAP) analysis, functional enrichment analysis, and immune infiltration analysis. Finally, we screened the hub gene using the STRING database and validated it via experiments. In this way, we constructed a model with good accuracy and robustness, which was composed of seven anoikis- and EMT-related genes. Paclitaxel and mesna were selected as potential chemotherapeutic drugs and adjuvant chemotherapeutic drugs for the WT high-risk group by using the Genomics of Drug Sensitivity in Cancer (GDSC) and cMAP compound libraries, respectively. We proved the existence of a strong correlation between invasive immune cells and prognostic genes and risk scores. Next, we selected NTRK2 as the hub gene, and in vitro experiments confirmed that its inhibition can significantly inhibit the proliferation and migration of tumor cells and promote late apoptosis. In summary, we screened out the potential biomarkers and chemotherapeutic drugs that can improve the prognosis of patients with WT.

Radiomics in differential diagnosis of Wilms tumor and neuroblastoma with adrenal location in children

OBJECTIVES

Machine learning methods can be applied successfully to various medical imaging tasks. Our aim with this study was to build a robust classifier using radiomics and clinical data for preoperative diagnosis of Wilms tumor (WT) or neuroblastoma (NB) in pediatric abdominal CT.

MATERIAL AND METHODS

This is a single-center retrospective study approved by the Institutional Ethical Board. CT scans of consecutive patients diagnosed with WT or NB admitted to our hospital from January 2005 to December 2021 were evaluated. Three distinct datasets based on clinical centers and CT machines were curated. Robust, non-redundant, high variance, and relevant radiomics features were selected using data science methods. Clinically relevant variables were integrated into the final model. Dice score for similarity of tumor ROI, Cohen's kappa for interobserver agreement among observers, and AUC for model selection were used.

RESULTS

A total of 147 patients, including 90 WT (mean age 34.78 SD: 22.06 months; 43 male) and 57 NB (mean age 23.77 SD:22.56 months; 31 male), were analyzed. After binarization at 24 months cut-off, there was no statistically significant difference between the two groups for age (p = .07) and gender (p = .54). CT clinic radiomics combined model achieved an F1 score of 0.94, 0.93 accuracy, and an AUC 0.96.

CONCLUSION

In conclusion, the CT-based clinic-radiologic-radiomics combined model could noninvasively predict WT or NB preoperatively. Notably, that model correctly predicted two patients, which none of the radiologists could correctly predict. This model may serve as a noninvasive preoperative predictor of NB/WT differentiation in CT, which should be further validated in large prospective models.

CLINICAL RELEVANCE STATEMENT

CT-based clinic-radiologic-radiomics combined model could noninvasively predict Wilms tumor or neuroblastoma preoperatively.

KEY POINTS

• CT radiomics features can predict Wilms tumor or neuroblastoma from abdominal CT preoperatively. • Integrating clinic variables may further improve the performance of the model. • The performance of the combined model is equal to or greater than human readers, depending on the lesion size.

Nephrectomy for Pediatric Renal Tumors: A Modified Surgical Approach to Minimize Post-operative Intestinal Obstruction

BACKGROUND

The authors present a modified surgical technique during tumor nephrectomy in children with a conservative approach towards small bowel manipulation and cutting of the peritoneal reflections. We aimed to evaluate this modified surgical approach regarding the incidence of post-operative small bowel obstruction (SBO), and its technical utility.

METHODS

The study includes all children with unilateral renal tumors who underwent radical nephrectomy and lymph nodes sampling at our tertiary center from 2010 to 2022. The modified technique was performed via the usual transverse incision. We cut the peritoneal reflections short of the cecum or short of the sigmoid colon. The colon is reflected over SB packing it, proceeding to nephrectomy and lymph nodes sampling. Data included demographics, clinical characteristics, treatment strategy, operative details, post-operative SBO, and overall outcomes.

RESULTS

The study included 890 patients with a median age of 3.2 years. The median tumor largest diameter was 13 cm (range: 9-18 cm). The modified surgical technique was adopted in 287 patients (32.3 %). Forty-three patients (43/890, 4.8 %) had post-operative SBO. Out of them, only 4 cases were operated on using the modified surgical technique (p-value<0.001). There were no significant differences between both techniques regarding timing of surgery, tumor rupture, lymph nodes sampling, and tumor size (p-value = 0.775, 0.328, 0.216, and 0.563, respectively).

CONCLUSIONS

The modified surgical approach is significantly correlated with lower incidence of post-operative SBO with no increased risk of tumor rupture or incomplete lymph nodes sampling. The timing of surgery or tumor characteristics had no significant impact on the technical utility of the modified surgical approach.

LEVEL OF EVIDENCE

Level IV.

Current surgical approaches to pediatric renal tumors

Pediatric renal tumors are among the most common pediatric solid malignancies. Surgical resection is a key component in the multidisciplinary therapy for children with kidney tumors. Therefore, it is imperative that surgeons caring for children with renal tumors fully understand the current standards of care in order to provide appropriate surgical expertise within this multimodal framework. Fortunately, the last 60 years of international, multidisciplinary pediatric cancer cooperative group studies have enabled high rates of cure for these patients. This review will highlight the international surgical approaches to pediatric patients with kidney cancer to help surgeons understand the key differences and similarities between the European (International Society of Pediatric Oncology) and North American (Children's Oncology Group) recommendations.

Oncogenic Cells of Renal Embryonic Lineage Sensitive to the Small-Molecule Inhibitor QC6352 Display Depletion of KDM4 Levels and Disruption of Ribosome Biogenesis

The histone lysine demethylases KDM4A-C are involved in physiologic processes including stem cell identity and self-renewal during development, DNA damage repair, and cell-cycle progression. KDM4A-C are overexpressed and associated with malignant cell behavior in multiple human cancers and are therefore potential therapeutic targets. Given the role of KDM4A-C in development and cancer, we aimed to test the potent, selective KDM4A-C inhibitor QC6352 on oncogenic cells of renal embryonic lineage. The anaplastic Wilms tumor cell line WiT49 and the tumor-forming human embryonic kidney cell line HEK293 demonstrated low nanomolar QC6352 sensitivity. The cytostatic response to QC6352 in WiT49 and HEK293 cells was marked by induction of DNA damage, a DNA repair-associated protein checkpoint response, S-phase cell-cycle arrest, profound reduction of ribosomal protein gene and rRNA transcription, and blockade of newly synthesized proteins. QC6352 caused reduction of KDM4A-C levels by a proteasome-associated mechanism. The cellular phenotype caused by QC6352 treatment of reduced migration, proliferation, tumor spheroid growth, DNA damage, and S-phase cell-cycle arrest was most closely mirrored by knockdown of KDM4A as determined by siRNA knockdown of KDM4A-C. QC6352 sensitivity correlated with high basal levels of ribosomal gene transcription in more than 900 human cancer cell lines. Targeting KDM4A may be of future therapeutic interest in oncogenic cells of embryonic renal lineage or cells with high basal expression of ribosomal protein genes.

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.

Lung relapse pattern in children with metastatic Wilms tumor

Wilms tumor is the most common pediatric renal cancer, and lungs represent the major site of metastasis and recurrence. Relapse occurs in 15%, months or years after treatment; so due to the small sample, acquiring more data about the pattern of lung relapse remains a challenge. The aim of our study was to evaluate if pulmonary relapse, detected by computed tomography (CT), occurred at the initial site of lung metastases or in a different location. According to our data, the CT pattern of lung relapse showed high probability of recurrence at the same site of initial metastasis.

Hepatic Metastasectomy in Pediatric Patients: An Observational Study

BACKGROUND

The role of hepatectomy for metastatic disease in children is controversial. Rationales include potential cure, obtaining a diagnosis, and guiding chemotherapy decisions. This study examines the safety and utility of hepatic metastasectomy for children at a single institution.

METHODS

After IRB approval (#22-1258), medical records were reviewed from 1995 to 2022 for children undergoing hepatic metastasectomy. En-bloc hepatectomies during primary tumor resection were excluded.

RESULTS

Hepatic metastasectomy was performed in 16 patients for a variety of histologies. Median patient age was 12.2 years [IQR 6.9-22.6], and 13/16 patients were female (81 %). Number of hepatic metastases ranged from 1 to 23 and involved between 1 and 8 Couinaud segments. Anatomic resections included 4 hemihepatectomies and 1 sectionectomy. All other resections were nonanatomic. 3/6 resections for germ cell tumor (GCT) revealed only mature teratoma, driving adjuvant therapy decisions. When indicated, median time to adjuvant chemotherapy was 19 days [IQR 11-22]. No patients had Clavien-Dindo Class III or higher perioperative morbidity. Three patients (1 GCT, 1 adrenocortical carcinoma (ACC), and 1 gastric neuroendocrine tumor (GNET) experienced hepatic relapse. The patients with relapsed GCT and GNET are alive with disease at 17 and 135 months, respectively. The patient with ACC died of disease progression and liver failure. One patient with Wilms tumor experienced extrahepatic, retroperitoneal recurrence and died. With a median follow-up of 38 months, 10-year disease-specific and disease-free survival were 77 % and 61 %, respectively.

CONCLUSIONS

Hepatic metastasectomy can be accomplished safely in children, may guide adjuvant therapy decisions, and is associated with long-term survival in selected patients.

LEVEL OF EVIDENCE

Level IV.

TYPE OF STUDY

Treatment Study, Case series with no comparison group.

Unusual Metastatic Patterns of Wilms Tumor: A Case Series

Wilms tumor (WT) is the most common renal malignancy of childhood. The common metastatic sites are the lungs, liver, and lymph nodes, with brain and bone metastases occurring rarely. Metastatic disease can be present at initial diagnosis or may occur with relapse or disease progression. The majority of relapses in WT occur within the first two years post-treatment. Late relapses are rare. This article describes four cases of WT, each demonstrating an unusual site or timing of metastases. Case 1 presented primarily with jaw metastases, Case 2 presented with bone (vertebrae) and spinal metastases manifesting as paraplegia, at relapse one year after completion of treatment, Case 3 presented with isolated liver metastases four years after treatment completion, and Case 4 presented with brain metastases after six weeks of treatment abandonment. This case series demonstrates the varied pattern of metastases of WT and highlights the need for a high index of suspicion for WT among patients who present with unusual sites of tumor or for metastasis in those who present with neurologic symptoms during or after treatment.

A novel model incorporating chromatin regulatory factors for risk stratification, prognosis prediction, and characterization of the microenvironment in Wilms tumor

BACKGROUND

Wilms tumor, also known as nephroblastoma, a pediatric most-frequent malignant-kidney tumor, may be regulated and influenced by transcriptional and epigenetic mechanisms. Chromatin regulatory factors (CRs) play key roles in epigenetic regulation. The present study aimed to explore the involvement of CRs in the development of nephroblastoma.

METHODS

RNA-sequencing and clinical information of nephroblastoma samples were obtained by downloading data from the TARGET database. The Limma package was utilized to perform differential expression analysis of genes (DEGs) between the tumor group and the control group. A Venn map was used for intersection of differential genes and CRs and to perform Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment analysis of DEGs using the clusterProfiler package. LASSO and Cox analyses were used to construct CR-related risk models and were evaluated based on clinical parameters. A receiver operating characteristic curve was employed to assess the diagnostic performance of risk model. Furthermore, we used a single-sample gene set enrichment analysis algorithm for immune cell infiltration analysis. Finally, to confirm the transcriptome expression of pivotal genes in human nephroblastoma cell lines, a quantitative real-time PCR was employed.

RESULTS

Fifteen key CRs were obtained through analysis in nephroblastoma and then the risk model based on 13 important CRs was constructed using the transcriptome data of nephroblastoma. Using the risk model, pediatric nephroblastoma patients were stratified into high- and low-risk groups based on their individual risk scores. The risk score of CRs can predict adverse outcomes in pediatric nephroblastoma, and this gene cluster is closely related to various immunity characteristics of nephroblastoma. Moreover, the nephroblastoma cell line exhibited higher expression levels of prognostic genes (VRK1, ARNTL, RIT1, PRDM6, and TSPY1) compared to the HEK293 T cell line.

CONCLUSIONS

The risk characteristics derived from CRs have tremendous significance in predicting prognosis and guiding clinical classification and intervention strategies for pediatric nephroblastoma.

Redo nephron-sparing surgery in stage V pediatric renal tumors - A report from the SIOP/GPOH study group for renal tumors

PURPOSE

Nephron-sparing Surgery (NSS) is the surgical treatment of choice in children with bilateral renal tumors or in syndromatic patients. With an increasing role of this surgical approach, there is also an increased number of tumor relapses after NSS. Aim of this study was to evaluate a second ("Redo-") NSS in children with relapsed renal tumors.

MATERIALS AND METHODS

We retrospectively analysed patients undergoing Redo-NSS for relapsed kidney tumors between 2009 and 2021 at our institution, which represents a national reference center of the SIOP/GPOH renal tumor study group.

RESULTS

Nine patients (5 girls, 4 boys) underwent Redo-NSS with resection of 15 lesions. Mean age at surgery was 58 months (12-137), mean operative time for Redo-NSS was 195 min (137-260). R0 resection status was achieved in all children. Two patients had second relapses, one of them was resected via NSS, the other child underwent tumor nephrectomy. Two patients with anaplastic relapses died from combined second relapses. Thus, 7/9 patients are alive without evidence of disease, an impaired renal function was observed in one child. Mean follow-up after Redo-NSS was 35 months (6-49).

CONCLUSIONS

In renal tumor relapses, Redo-NSS can be performed with satisfactory oncological and functional results. Occurrence of diffuse anaplasia should possibly refrain from this approach. Further evaluation in international multicenter analyses are necessary for a definitive determination of Redo-NSS.

Genetic and epigenetic features of bilateral Wilms tumor predisposition in patients from the Children's Oncology Group AREN18B5-Q

Developing synchronous bilateral Wilms tumor suggests an underlying (epi)genetic predisposition. Here, we evaluate this predisposition in 68 patients using whole exome or genome sequencing (n = 85 tumors from 61 patients with matched germline blood DNA), RNA-seq (n = 99 tumors), and DNA methylation analysis (n = 61 peripheral blood, n = 29 non-diseased kidney, n = 99 tumors). We determine the predominant events for bilateral Wilms tumor predisposition: 1)pre-zygotic germline genetic variants readily detectable in blood DNA [WT1 (14.8%), NYNRIN (6.6%), TRIM28 (5%), and BRCA-related genes (5%)] or 2)post-zygotic epigenetic hypermethylation at 11p15.5 H19/ICR1 that may require analysis of multiple tissue types for diagnosis. Of 99 total tumor specimens, 16 (16.1%) have 11p15.5 normal retention of imprinting, 25 (25.2%) have 11p15.5 copy neutral loss of heterozygosity, and 58 (58.6%) have 11p15.5 H19/ICR1 epigenetic hypermethylation (loss of imprinting). Here, we ascertain the epigenetic and genetic modes of bilateral Wilms tumor predisposition.

Identification of m6A-associated genes as prognostic and immune-associated biomarkers in Wilms tumor

OBJECTIVES

Wilms tumor (WT) is a common renal malignant tumor in children. We aimed to investigate the potential prognostic value of m6A-related genes and their relationship to the immune microenvironment in WT.

METHODS

RNA-seq data and clinical information from 121 WT and 6 normal samples were obtained from the University of California Santa Cruz Xena database. We used various bioinformatics analysis tools to analyze these data and verify the expression level of m6A-related genes by experiments.

RESULTS

Four m6A-related genes were successfully screened, including ADGRG2, CPD, CTHRC1, and LRTM2. Kaplan-Meier survival curves showed that the four genes were closely related to the prognosis of WT, which was also confirmed by receiver operator characteristic curves. Subsequently, in the immune microenvironment of WT, we discovered that Th1_cells were positively correlated with ADGRG2, CCR was negatively correlated with CPD, CCR was positively correlated with CTHRC1, APC_co_stimulation, CCR, Macrophages, inflammation-promoting cells, Treg, and Type_II_IFN_Reponse were negatively correlated with LRTM2. Finally, qRT-PCR showed that expression levels of the four genes were upregulated in the nephroblastoma cell lines (G-401, SK-NEP-1, and WT-CLS1) compared with the human embryonic kidney cell lines (293T).

CONCLUSIONS

Taken together, our study first time screened the m6A-related genes and revealed that ADGRG2, CPD, CTHRC1, and LRTM2 are the prognostic and immune-associated biomarkers in WT.

Surgery in Bilateral Wilms Tumor-A Single-Center Experience

The treatment of bilateral Wilms tumors (BWT) involves curing the cancer, preserving long-term renal function, and maintaining a good quality of life. Established methods for achieving these goals include preoperative chemotherapy and nephron-sparing surgery (NSS). This study aimed to evaluate the experience of a single institution in treating patients with BWT. We analyzed cases of BWT treated at the Pediatric Oncology Institute-GRAACC-Federal University of São Paulo over a period of 35 years. Bleeding control was performed with manual compression of the renal parenchyma. Thirty-three patients were included in the study. Thirty cases were synchronous tumors. The mean age at diagnosis was 30.4 months (±22 m) and 66.7% were girls. The median follow-up period was 83 months. Neoadjuvant chemotherapy was the primary approach in most patients (87.9%), with a simultaneous upfront surgical approach performed in 84.8%. Most patients underwent bilateral NSS (70.4%). There were no early complications in this series, but 39.4% had clinical complications. The five-year survival rate was 76%. Therefore, it is clear that the surgical approach to BWT plays a crucial role in achieving good outcomes. However, it is difficult to standardize surgical techniques and technology may have the potential to enhance safety.

Wilms tumor in horseshoe kidney with extensive vascular thrombosis: A case report

INTRODUCTION AND IMPORTANCE

Wilms tumor (WT), a prevalent pediatric renal malignancy (7 %), frequently intertwines with genitourinary anomalies. This unique report presents a case of WT combined with horseshoe Kidney and an extending atrial thrombus, emphasizing critical management considerations.

CASE PRESENTATION

A 3-year-old boy, experiencing flank pain and weight loss, manifested a WT linked to horseshoe Kidney, accompanied by an atrial thrombus. Neoadjuvant chemotherapy downsized the tumor and thrombus, enabling successful surgical intervention. Post-surgery, 27 weeks of adjuvant chemotherapy were administered. Over three years, follow-up exhibited renal recovery, no recurrence, and clear CT scans.

DISCUSSION

Prompt identification, precise imaging (via CT angiography), and multidisciplinary care are pivotal for managing WT in horseshoe Kidney cases. Preoperative chemotherapy notably reduced tumor and thrombus sizes, enhancing surgical feasibility. Long-term vigilance is essential for recurrence and treatment-related complications.

CONCLUSION

Effectively managing WT in horseshoe Kidneys demands timely recognition, meticulous imaging, and collaborative management. Successful outcomes highlight preoperative chemotherapy's benefits and underscore extended monitoring's significance in confirming sustained recovery.

Identification of the expression patterns and potential prognostic role of m6A-RNA methylation regulators in Wilms Tumor

BACKGROUND

To explore the potential role of m6A methylation modification in Wilms Tumor (WT) by m6A-RNA Methylation (m6A) regulators.

METHODOLOGY

The association of m6A modification patterns with immune and prognostic characteristics of tumors was systematically evaluated using 19 m6A regulators extracted from Wilms Tumor's samples in public databases. A comprehensive model of "m6Ascore" was constructed using principal component analysis, and its prognostic value was evaluated.

RESULTS

Almost all m6A regulators were differentially expressed between WT and normal tissues. Unsupervised clustering identified three distinct m6A clusters that differed in both immune cell infiltration and biological pathways. The m6Ascore was constructed to quantify m6A modifications in individual patients. Our analysis suggests that m6Ascore is an independent prognostic factor for WT and can be used as a novel predictor of WT prognosis.

CONCLUSIONS

This study comprehensively explored and systematically characterized m6A modifications in WT. m6A modification patterns play a critical role in the tumor immune microenvironment (TIME) and WT prognosis. m6Ascore provides a more comprehensive understanding of m6A modifications in WT and offers a practical tool for predicting WT prognosis. This study will help clinicians to identify valid indicators of WT to improve the poor prognosis of this disease.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at https://www.aliyundrive.com/drive/folder/64be739cd6956a741fb24670baeea53422be6024 .

CCNB1 is a novel prognostic biomarker and promotes proliferation, migration and invasion in Wilms tumor

BACKGROUND

Wilms tumour (WT) is a mixed type of embryonal tumour that usually occurs in early childhood. However, our knowledge of the pathogenesis or progression mechanism of WT is inadequate, and there is a scarcity of beneficial therapeutic strategies.

METHODS

High-throughput RNA sequencing was employed in this study to identify differentially expressed genes (DEGs) in clinical tumor samples and matching normal tissues. The STRING database was utilized to build a protein-protein interaction (PPI) network, and the Cytohubba method was used to identify the top 10 highly related HUB genes. Then, the key genes were further screened by univariate COX survival analysis. Subsequently, the XCELL algorithm was used to evaluate the tumour immune infiltration. RT-PCR, WB, and IF were used to verify the expression level of key genes in clinical tissues and tumour cell lines. Finally, the function of the key gene was further verified by loss-of-function experiments.

RESULTS

We initially screened 1612 DEGs, of which 1030 were up-regulated and 582 were down-regulated. The GO and KEGG enrichment analysis suggested these genes were associated with 'cell cycle', 'DNA replication'. Subsequently, we identified 10 key HUB genes, among them CCNB1 was strongly related to WT patients' overall survival. Multiple survival analyses showed that CCNB1 was an independent indicator of WT prognosis. Thus, we constructed a nomogram of CCNB1 combined with other clinical indicators. Single gene GSEA and immune infiltration analysis revealed that CCNB1 was associated with the degree of infiltration or activation status of multiple immune cells. TIDE analysis indicated that this gene was correlated with multiple key immune checkpoint molecules and TIDE scores. Finally, we validated the differential expression level of CCNB1 in an external gene set, the pan-cancer, clinical samples, and cell lines. CCNB1 silencing significantly inhibited the proliferation, migration, and invasive capabilities of WIT-49 cells, also, promoted apoptosis, and in turn induced G2 phase cell cycle arrest in loss-of-function assays.

CONCLUSION

Our study suggests that CCNB1 is closely related to WT progression and prognosis, and serves as a potential target.

Identification and Characterization of the Wilms Tumor Cancer Stem Cell

A nephrogenic progenitor cell (NP) with cancer stem cell characteristics driving Wilms tumor (WT) using spatial transcriptomics, bulk and single cell RNA sequencing, and complementary in vitro and transplantation experiments is identified and characterized. NP from WT samples with NP from the developing human kidney is compared. Cells expressing SIX2 and CITED1 fulfill cancer stem cell criteria by reliably recapitulating WT in transplantation studies. It is shown that self-renewal versus differentiation in SIX2+CITED1+ cells is regulated by the interplay between integrins ITGβ1 and ITGβ4. The spatial transcriptomic analysis defines gene expression maps of SIX2+CITED1+ cells in WT samples and identifies the interactive gene networks involved in WT development. These studies define SIX2+CITED1+ cells as the nephrogenic-like cancer stem cells of WT and points to the renal developmental transcriptome changes as a possible driver in regulating WT formation and progression.

The Genetic and Epigenetic Features of Bilateral Wilms Tumor Predisposition: A Report from the Children's Oncology Group AREN18B5-Q Study

This study comprehensively evaluated the landscape of genetic and epigenetic events that predispose to synchronous bilateral Wilms tumor (BWT). We performed whole exome or whole genome sequencing, total-strand RNA-seq, and DNA methylation analysis using germline and/or tumor samples from 68 patients with BWT from St. Jude Children's Research Hospital and the Children's Oncology Group. We found that 25/61 (41%) of patients evaluated harbored pathogenic or likely pathogenic germline variants, with WT1 (14.8%), NYNRIN (6.6%), TRIM28 (5%) and the BRCA-related genes (5%) BRCA1, BRCA2, and PALB2 being most common. Germline WT1 variants were strongly associated with somatic paternal uniparental disomy encompassing the 11p15.5 and 11p13/WT1 loci and subsequent acquired pathogenic CTNNB1 variants. Somatic coding variants or genome-wide copy number alterations were almost never shared between paired synchronous BWT, suggesting that the acquisition of independent somatic variants leads to tumor formation in the context of germline or early embryonic, post-zygotic initiating events. In contrast, 11p15.5 status (loss of heterozygosity, loss or retention of imprinting) was shared among paired synchronous BWT in all but one case. The predominant molecular events for BWT predisposition include pathogenic germline variants or post-zygotic epigenetic hypermethylation at the 11p15.5 H19/ICR1 locus (loss of imprinting). This study demonstrates that post-zygotic somatic mosaicism for 11p15.5 hypermethylation/loss of imprinting is the single most common initiating molecular event predisposing to BWT. Evidence of somatic mosaicism for 11p15.5 loss of imprinting was detected in leukocytes of a cohort of BWT patients and long-term survivors, but not in unilateral Wilms tumor patients and long-term survivors or controls, further supporting the hypothesis that post-zygotic 11p15.5 alterations occurred in the mesoderm of patients who go on to develop BWT. Due to the preponderance of BWT patients with demonstrable germline or early embryonic tumor predisposition, BWT exhibits a unique biology when compared to unilateral Wilms tumor and therefore warrants continued refinement of its own treatment-relevant biomarkers which in turn may inform directed treatment strategies in the future.

Nephron-sparing surgery for Wilms tumor

The algorithm that has been used successfully in the surgical management of unilateral Wilms tumor, radical nephroureterectomy, cannot be used in children who present with synchronous bilateral renal masses. Instead, a surgical approach that removes all tumor masses while preserving as much normal renal parenchyma as possible is encouraged to avoid acute and long-term renal insufficiency. We will review technical aspects of the conduct of nephron-sparing surgery for synchronous bilateral Wilms tumor, including the more recent advances in the use of imaging adjuncts such as pre-operative 3D imaging and fluorescence-guided surgery. The potential role of nephron-sparing surgery for unilateral Wilms tumor will also be discussed.

Outcomes according to treatment using an established protocol in patients with bilateral Wilms' tumor: A national Canadian population-based study

BACKGROUND

Bilateral Wilms tumor (BWT) is a rare entity. The goal of this study is to report outcomes (overall and event-free survival, OS/EFS) of BWT in a large cohort representative of the Canadian population since 2000. We focused on the occurrence of late events (relapse or death beyond 18 months), as well as outcomes of patients treated following the only protocol specifically designed for BWT to date, AREN0534, compared to patients treated following other therapeutic schemes.

METHODS

Data was obtained for patients diagnosed with BWT between 2001 and 2018 from the Cancer in Young People in Canada (CYP-C) database. Demographics, treatment protocols, and dates for events were collected. Specifically, we examined outcomes of patients treated according to the Children's Oncology Group (COG) protocol AREN0534 since 2009. Survival analysis was performed.

RESULTS

57/816 (7%) of patients with Wilms tumor had BWT during the study period. Median age at diagnosis was 2.74 years (IQR 1.37-4.48) and 35 (64%) were female; 8/57 (15%) had metastatic disease. After a median follow-up of 4.8 years (IQR 2.8-5.7 years, range 0.2-18 years), OS and EFS were 86% (CI 73-93%) and 80% (CI 66-89%), respectively. Less than 5 events were recorded after 18 months from diagnosis. Since 2009, patients treated according to the AREN0534 protocol had a statistically significant higher OS compared to patients treated with other protocols.

CONCLUSIONS

In this large Canadian cohort of patients with BWT, OS and EFS compared favorably to the published literature. Late events were rare. Patients treated according to a disease-specific protocol (AREN0534) had improved overall survival.

TYPE OF STUDY

Original article.

LEVEL OF EVIDENCE

Level IV.

Vaginal metastases of Wilms' Tumor in a pediatric patient: a rare case

BACKGROUND

Wilms' tumor is the second most common pediatric abdominal cancer, however, it rarely involves the female reproductive tract. There are few cases reported in the literature describing uterine, ovarian, cervical and vaginal involvement.

CASE

We report the case of a 7-year-old girl presenting with a large renal mass with retroperitoneal nodal and lung metastases; she was diagnosed with stage 4 favorable histology Wilms' tumor. She was treated with surgery, chemotherapy and radiation. She presented with vaginal bleeding 10 months after completing treatment; biopsy of a vaginal mass confirmed recurrence, and this was sent for molecular profiling, which did not identify an inherited cancer predisposition or targetable mutation. She was again treated with chemotherapy; examination redemonstrated a small vaginal mass, but re-biopsy of the lesion was negative for malignancy. Due to high risk of local relapse, ongoing chemotherapy and pelvic radiation ensued. End of treatment imaging and vaginoscopy showed no residual disease.

SUMMARY AND CONCLUSION

Vaginal metastases of Wilms' tumor are very rare; this is the second reported case in the literature. Pediatric clinicians should have a strong suspicion for vaginal metastases in cancer patients presenting with vaginal bleeding especially when their pubertal development does not suggest that bleeding would be secondary to menarche. Long-term gynecologic care for these patients is paramount to reduce morbidity from chemotherapy and pelvic radiation. Fertility preservation counselling should be made early, through referral to a specialist.

Etiologies, Gross Appearance, Histopathological Patterns, Prognosis, and Best Treatments for Subtypes of Renal Carcinoma: An Educational Review

Of all primary renal neoplasms, 80-85% are renal cell carcinomas (RCCs), which develop in the renal cortex. There are more than 10 histological and molecular subtypes of the disease, the most frequent of which is clear cell RCC, which also causes most cancer-related deaths. Other renal neoplasms, including urothelial carcinoma, Wilms' tumor, and renal sarcoma, each affect a particular age group and have specific gross and histological features. Due to the genetic susceptibility of each of these malignancies, early mutation discovery is necessary for the early detection of a tumor. Furthermore, it is crucial to avoid environmental factors leading to each type. This study provides relatively detailed and essential information regarding each subtype of renal carcinoma.

Fluorescence-guided lymph node sampling is feasible during up-front or delayed nephrectomy for Wilms tumor

BACKGROUND

Lymph node sampling is critical to surgical staging in Wilms tumor; failure to sample lymph nodes is associated with under-staging and an increased incidence of local relapse. However, no standard lymphatic mapping method is currently being utilized for Wilms tumor to aid identification of regional draining lymph nodes. Herein, we describe the use of fluorescence-guided lymphatic mapping for Wilms tumor.

MATERIALS AND METHODS

Two tertiary level referral centers independently began indocyanine green (ICG) fluorescence-guided nodal mapping. In one center, this was achieved with ipsilateral intra-parenchymal (IP) injection of ICG during minimally invasive tumor nephrectomy (MIN) following neoadjuvant chemotherapy and in the other, with Peri‑Hilar (PH) injection during upfront, open tumor nephrectomy (ON). Successful lymph node mapping was defined as the presence of fluorescence signal in draining lymph nodes.

RESULTS

Eight patients (median age of 2.5 years) underwent fluorescence-guided lymphatic mapping (four IP and four PH injection). Lymphatic mapping was successful in seven patients (88%) including each of the four patients with IP injection.

CONCLUSIONS

Fluorescence-guided lymphatic mapping of Wilms tumor drainage is feasible by both IP injection and PH injection techniques. However, whether lymphatic mapping improves the precision of lymph node sampling is unknown and should be studied in prospective trials.

Characterization of alternative mRNA splicing in cultured cell populations representing progressive stages of human fetal kidney development

Nephrons are the functional units of the kidney. During kidney development, cells from the cap mesenchyme-a transient kidney-specific progenitor state-undergo a mesenchymal to epithelial transition (MET) and subsequently differentiate into the various epithelial cell types that create the tubular structures of the nephron. Faults in this transition can lead to a pediatric malignancy of the kidney called Wilms' tumor that mimics normal kidney development. While human kidney development has been characterized at the gene expression level, a comprehensive characterization of alternative splicing is lacking. Therefore, in this study, we performed RNA sequencing on cell populations representing early, intermediate, and late developmental stages of the human fetal kidney, as well as three blastemal-predominant Wilms' tumor patient-derived xenografts. Using this newly generated RNAseq data, we identified a set of transcripts that are alternatively spliced between the different developmental stages. Moreover, we found that cells from the earliest developmental stage have a mesenchymal splice-isoform profile that is similar to that of blastemal-predominant Wilms' tumor xenografts. RNA binding motif enrichment analysis suggests that the mRNA binding proteins ESRP1, ESRP2, RBFOX2, and QKI regulate alternative mRNA splicing during human kidney development. These findings illuminate new molecular mechanisms involved in human kidney development and pediatric kidney cancer.

Challenges in the Management of Wilms Tumor in a Developing Country: A Twenty Years' Experience From a Single Center in Pakistan

BACKGROUND

Wilms Tumor (WT) is one of the most curable childhood cancers. High cure rates seen in the developed countries are not reproduced in developing countries. Lack of access to cancer treatment facilities, financial constraints, late presentation, and abandonment have previously been described. We reviewed our data over the last 20 years to highlight some of these challenges.

METHODS

This is a retrospective chart review of children with WT at our center up to the age of 18 years between 1 November 1997 and 30 November 2017. Demographic details, presentation characteristics and treatment details were recorded. Factors associated with poor outcome were analyzed.

RESULTS

Two hundred eleven children were registered; 117(55.5%) were males. Median age at presentation was 3 (range 0 to 18) years. Presentation data were available for 184/211 patients, staging details for 159/211 and metastatic status for 178/211. Of the available dataset, 60% presented without prior treatment, whereas 40% presented atleast after primary surgical excision. High-stage (stage III or above) disease was present in 79 (49.7%) patients; 61 (34.3%) was presented with metastases or recurrence; 63 (29.8%) abandoned or refused treatment; 99/172 (57.6%) patients finished treatment, 23 (13.4%) died during treatment, and 6 died before treatment. Of the 99 patients who finished treatment 83 (83.8%) are well off therapy; 15(15.2%) relapsed; 6 (40%) are alive after salvage therapy, while 9 (60%) died.

CONCLUSIONS

Our data highlights the challenges of managing WT in resource poor environments. Prior surgery, incomplete staging work-up and abandonment are some of the most frequently encountered barriers. A multipronged approach is required to overcome these challenges.

Nucleic acid therapy in pediatric cancer

The overall survival, progress free survival, and life quality of cancer patients have improved due to the advance in minimally invasive surgery, precision radiotherapy, and various combined chemotherapy in the last decade. Furthermore, the discovery of new types of therapeutics, such as immune checkpoint inhibitors and immune cell therapies have facilitated both patients and doctors to fight with cancers. Moreover, in the context of the development in biocompatible and cell type targeting nano-carriers as well as nucleic acid-based drugs for initiating and enhancing the anti-tumor response have come to the age. The treatment paradigms utilization of nucleic acids, including short interfering RNA (siRNA), antisense oligonucleotides (ASO), and messenger RNA (mRNA), can target specific protein expression to achieve the therapeutic effects. Over ten nucleic acid therapeutics have been approved by the FDA and EMA in rare diseases and genetic diseases as well as dozens of registered clinical trails for varies cancers. Though generally less dangerous of pediatric cancers than adult cancers was observed during the past decades, yet pediatric cancers accounted for a significant proportion of child deaths which hurt those family very deeply. Therefore, it is necessary to pay more attention for improving the treatment of pediatric cancer and discovering new nucleic acid therapeutics which may help to improve the therapeutic effect and prognoses in turns to ameliorate the survival period and quality of life for children patient. In this review, we focus on the nucleic acid therapy in pediatric cancers.

Incidence and Management of Pleural Effusions in Patients with Wilms Tumor: A Pediatric Surgical Oncology Research Collaborative Study

Wilms tumor (WT) is the most common renal malignancy in children. Children with favorable histology WT achieve survival rates of over 90%. Twelve percent of patients present with metastatic disease, most commonly to the lungs. The presence of a pleural effusion at the time of diagnosis of WT may be noted on staging imaging; however, minimal data exist regarding the significance and prognostic importance of this finding. The objectives of this study are to identify the incidence of pleural effusions in patients with WT, and to determine the potential impact on oncologic outcomes. A multi-institutional retrospective review was performed from January 2009 to December 2019, including children with WT and a pleural effusion on diagnostic imaging treated at Pediatric Surgical Oncology Research Collaborative (PSORC) participating institutions. Of 1,259 children with a new WT diagnosis, 94 (7.5%) had a pleural effusion. Patients with a pleural effusion were older than those without (median 4.3 vs 3.5 years; p=0.004), and advanced stages were more common (local stage III 85.9% vs 51.9%; p<0.0001). Only 14 patients underwent a thoracentesis for fluid evaluation; 3 had cytopathologic evidence of malignant cells. Event-free and overall survival of all children with WT and pleural effusions was 86.2% and 91.5%, respectively. The rate and significance of malignant cells present in pleural fluid is unknown due to low incidence of cytopathologic analysis in our cohort; therefore, the presence of an effusion does not appear to necessitate a change in therapy. Excellent survival can be expected with current stage-specific treatment regimens.

TERT Expression in Wilms Tumor Is Regulated by Promoter Mutation or Hypermethylation, WT1, and N-MYC

Simple Summary

The telomerase enzyme adds repetitive genetic sequences to the ends of chromosomes called telomeres to prevent cellular senescence. Gain of telomerase function is one of the hallmarks of human cancer. The telomerase protein is coded by the gene TERT and increased TERT RNA levels have been associated with disease relapse in Wilms tumor, the most common kidney cancer of childhood. This study aimed to determine the mechanisms of increased TERT expression in Wilms tumor. This study found mutations in the TERT promoter, increased methylation of the TERT promoter, and genomic copy number amplifications of TERT as potential mechanisms of TERT activation. Conversely, this study found that inactivating WT1 mutation was associated with low TERT RNA levels and telomerase activity. N-MYC overexpression in Wilms tumor cells resulted in increased TERT promoter activity and TERT transcription. TERT transcription is associated with molecular and histologic subgroups in Wilms tumor and telomere-targeted therapies warrant future investigation.

Abstract

Increased TERT mRNA is associated with disease relapse in favorable histology Wilms tumor (WT). This study sought to understand the mechanism of increased TERT expression by determining the association between TERT and WT1 and N-MYC, two proteins important in Wilms tumor pathogenesis that have been shown to regulate TERT expression. Three out of 45 (6.7%) WTs and the corresponding patient-derived xenografts harbored canonical gain-of-function mutations in the TERT promoter. This study identified near ubiquitous hypermethylation of the TERT promoter region in WT compared to normal kidney. WTs with biallelic inactivating mutations in WT1 (7/45, 15.6%) were found to have lower TERT expression by RNA-seq and qRT-PCR and lower telomerase activity determined by the telomerase repeat amplification protocol. Anaplastic histology and increased percentage of blastema were positively correlated with higher TERT expression and telomerase activity. In vitro shRNA knockdown of WT1 resulted in decreased expression of TERT, reduced colony formation, and decreased proliferation of WiT49, an anaplastic WT cell line with wild-type WT1. CRISPR-Cas9-mediated knockout of WT1 resulted in decreased expression of telomere-related gene pathways. However, an inducible Wt1-knockout mouse model showed no relationship between Wt1 knockout and Tert expression in normal murine nephrogenesis, suggesting that WT1 and TERT are coupled in transformed cells but not in normal kidney tissues. N-MYC overexpression resulted in increased TERT promoter activity and TERT transcription. Thus, multiple mechanisms of TERT activation are involved in WT and are associated with anaplastic histology and increased blastema. This study is novel because it identifies potential mechanisms of TERT activation in Wilms tumor that could be of therapeutic interests.

The role of m6A modification in pediatric cancer

With the development of RNA modification research, the importance of N6-methyladenosine (m6A) in tumors cannot be ignored. m6A promotes the self-renewal of tumor stem cells and the proliferation of tumor cells. It affects post-transcriptional gene expression through epigenetic mechanisms, combining various factors to determine proteins' fate and altering the biological function. This modification process runs through the entire tumors, and genes affected by m6A modification may be the critical targets for cancers breakthroughs. Though generally less dangerous than adult cancer, pediatric cancer accounts for a significant proportion of child deaths. What is more alarming is that the occurrences of adult tumors are highly associated with the poor prognoses of pediatric tumors. Therefore, it is necessary to pay attention to the importance of pediatric cancer and discover new therapeutic targets, which will help improve the therapeutic effect and prognoses of the diseases. We collected and investigated m6A modification in pediatric cancers based on mRNA and non-coding RNA, finding that m6A factors were involved in glioma, hepatoblastoma, nephroblastoma, neuroblastoma, osteosarcoma, medulloblastoma, retinoblastoma, and acute lymphoblastic leukemia. Consequently, we summarized the relationships between the m6A factors and these pediatric cancers.

Risk stratification of abdominal tumors in children with amide proton transfer imaging

OBJECTIVES

To evaluate the potential of molecular amide proton transfer (APT) MRI for predicting the risk group of abdominal tumors in children, and compare it with quantitative T1 and T2 mapping.

METHODS

This prospective study enrolled 133 untreated pediatric patients with suspected abdominal tumors from February 2019 to September 2020. APT-weighted (APTw) imaging and quantitative relaxation time mapping sequences were executed for each subject. The region of interest (ROI) was generated with automatic artifact detection and ROI-shrinking algorithms, within which the APTw, T1, and T2 indices were calculated and compared between different risk groups. The prediction performance of different imaging parameters was assessed with the receiver operating characteristics (ROC) analysis and Student's t-test.

RESULTS

Fifty-seven patients were included in the final analysis, including 24 neuroblastomas (NB), 18 Wilms' tumors (WT), and 15 hepatoblastomas (HB). The APTw signal was significantly (p < .001) higher in patients with high-risk NB than those with low-risk NB, while the difference between patients with low-risk and high-risk WT (p = .69) or HB (p = .35) was not statistically significant. The associated areas under the curve (AUC) for APT to differentiate low-risk and high-risk NB, WT, and HB were 0.93, 0.58, and 0.71, respectively. The quantitative T1 and T2 values generated AUCs of 0.61-0.70 for the risk stratification of abdominal tumors.

CONCLUSIONS

APT MRI is a potential imaging biomarker for stratifying the risk group of pediatric neuroblastoma in the abdomen preoperatively and provides added value to structural MRI.

KEY POINTS

• Amide proton transfer (APT) imaging showed significantly (p < .001) higher values in pediatric patients with high-risk neuroblastoma than those with low-risk neuroblastoma, but did not demonstrate a significant difference in patients with Wilms' tumor (p = .69) or hepatoblastoma (p = .35). • The associated areas under the curve (AUC) for APT to differentiate low-risk and high-risk neuroblastoma, Wilms' tumor, and hepatoblastoma were 0.93, 0.58, and 0.71, respectively. • The quantitative T1 and T2 indices generated AUCs of 0.61-0.70 for dichotomizing the risk group of abdominal tumors.

Timing of Adjuvant Chemotherapy after Laparotomy for Wilms Tumor and Neuroblastoma

PURPOSE

To describe the timing of chemotherapy initiation after surgery for Wilms tumor (WT) and neuroblastoma within a dedicated children's cancer center.

METHODS

A single-institution retrospective cohort study identified patients that underwent resection of unilateral WT or high-risk neuroblastoma and received adjuvant chemotherapy treatment. Adjuvant chemotherapy initiation and postoperative complications were recorded.

RESULTS

Among 47 WT patients, the median time to chemotherapy initiation was 11 days [interquartile range IQR 7-14]. 3 WT patients had post-operative complications, but all preceded chemotherapy. Among 83 patients treated for high-risk neuroblastoma, the median time to chemotherapy was 11 days [IQR 9-14]. High-risk neuroblastoma patients with 30-day postoperative complications had a significantly longer time to initiation of adjuvant chemotherapy (odds ratio 1.13; p = 0.008). Many of these complications preceded and delayed the initiation of post-operative chemotherapy. No complications occurred in the group of 12 (25%) WT patients or 16 (19.3%) neuroblastoma patients who started chemotherapy ≤ 7 days after surgery.

CONCLUSION

There is no association between early initiation of adjuvant chemotherapy and post-operative complications including wound healing. Early initiation of chemotherapy (≤ 7 days) is feasible in unilateral WT or high-risk neuroblastoma patients who are otherwise doing well without resulting in a preponderance of wound healing complications.

Report of a rare testicular teratoid Wilms Tumor in an adult patient

Although primarily a pediatric disease, nephroblastomas (also known as Wilms tumor) occur in adults at a rate of less than 0.2 cases per million per year. Rarer still are teratoid Wilms tumors, which arise from teratomas and therefore can be extrarenal. We describe the sixth recorded case of a testicular teratoid Wilms tumor in an adult patient with accompanying histological images of the specimen. Following the case, there is a brief discussion of the current literature.

Identification of a ferroptosis-related lncRNA signature with prognosis for Wilms tumor

BACKGROUND

Wilms tumor (WT) is a widespread urologic tumor in children. Ferroptosis, on the other hand, is a novel form of cell death associated with tumor development. In this study, we aim to explore the predictability of ferroptosis-related biomarkers in estimating prognosis in WT patients.

METHODS

To determine a link between ferroptosis-related gene expression and WT prognosis, we first collected RNA sequencing data and clinical information, involving 124 WT and 6 healthy tissue samples, from the TARGET database. Next, we screened the collected information for ferroptosis-related long non-coding RNA using Cox regression analysis, and constructed a signature model, as well as a nomogram, related to prognosis. Finally, we explored a potential link between ferroptosis-related lncRNA and tumor immunity and screened for possible immune checkpoints.

RESULTS

We constructed a WT prognosis prediction signature containing 12 ferroptosis-related lncRNAs. The area under the curves values, from the ROC curves, predicting overall survival rates at the 1, 3-, and 5-year timepoints were 0.775, 0.867, and 0.891 respectively. Moreover, we generated a nomogram, using clinical features and risk scores, carrying a C-index value of 0.836, which suggested a high predictive value. We also demonstrated significant differences in tumor immunity between low- and high-risk WT patients, particularly in the presence of B cells, NK cells, Th1 cells, Treg cells, inflammation promoting, and type I and II IFN responses. In addition, we showed that immune checkpoints like SIRPA, ICOSLG, LAG3, PVRIG, NECTIN1, and SIRPB2 can serve as potential therapeutic targets for WT.

CONCLUSIONS

Based on our analyses, we generated a ferroptosis-related lncRNA signature that can both estimate prognosis of WT patients and may provide basis for future WT therapy.

Silencing of long noncoding RNA MYLK-AS1 suppresses nephroblastoma via down-regulation of CCNE1 through transcription factor TCF7L2

Nephroblastoma, a pediatric kidney cancer, caused by pluripotent embryonic renal precursors. Long noncoding RNAs (lncRNAs) are commonly abnormal expressed in many cancers. In the present study, we fousced on one newly discrovered lncRNA, MYLK Antisense RNA 1 (MYLK-AS1), and its functional role in proliferation and cycle distribution of nephroblastoma cells. Micorarray-based analysis revealed the highly expressed Cyclin E1 (CCNE1) and MYLK-AS1 in nephroblastoma. After nephroblastoma tissue sample collection, RT-qPCR confirmed the upregulated expression of MYLK-AS1 and CCNE1 in nephroblastoma tissues and cells. Kaplan-Meier curve exhibited that patients with elevated CCNE1 had lower overall survival rate in follow-up study. RNA binding protein immunoprecipitation, chromatin immunoprecipitation, and dual-luciferase reporter gene assay were employed to determine the relationship among MYLK-AS1, TCF7L2, and CCNE1, which validated that transcription factor 7-like 2 (TCF7L2) could specifically bind to MYLK-AS1 and TCF7L2 could positively promote CCNE1. After gain- and loss-of function assays, the conclusion that silencing of MYLK-AS1 could inhibit expression of CCNE1 through the transcription factor TCF7L2 to regulate the cell proliferation and cell cycle distribution of nephroblastoma cells was obtained. Subsequently, the subcutaneous tumor formation ability of nephroblastoma cell in nude mice was observed and the silencing of MYLK-AS1 exerts suppressive role in the tumorigenic ability of nephroblastoma cells in vivo. Taken together, MYLK-AS1 constitutes a promising biomarker for the early detection and treatment of nephroblastoma.

Wilms tumor presenting as small bowel obstruction in a neonate: A diagnostic challenge

Wilms tumor is the most common primary malignant renal tumor of childhood which usually presents between 2 and 6 years of age. Its presentation in the neonatal period is extremely rare and presenting with intestinal obstruction is perhaps unknown. We report a 2-day-old baby girl who manifested features of acute upper gastrointestinal obstruction with frequent post-feeding vomiting and abdominal distension. The initial abdominal radiograph showed abnormally displayed small bowel loops to the right hemiabdomen. Subsequent ultrasound and computed tomography scan of the abdomen detected a massive left renal mass. Left-sided nephrectomy was performed, and histopathology demonstrated left-sided Wilms tumor with favorable histology. Post-treatment yearly follow-up for 5 years recorded a disease-free, normally thriving child.

The Role of Oxidative Stress and Inflammation in Cardiometabolic Health of Children During Cancer Treatment and Potential Impact of Key Nutrients

Significance: The 5-year survival rate of childhood cancers is now reaching 84%. However, treatments cause numerous acute and long-term side effects. These include cardiometabolic complications, namely hypertension, dyslipidemia, hyperglycemia, insulin resistance, and increased fat mass. Recent Advances: Many antineoplastic treatments can induce oxidative stress (OxS) and trigger an inflammatory response, which may cause acute and chronic side effects. Critical Issues: Clinical studies have reported a state of heightened OxS and inflammation during cancer treatment in children as the result of treatment cytotoxic action on both cancerous and noncancerous cells. Higher levels of OxS and inflammation are associated with treatment side effects and with the development of cardiometabolic complications. Key nutrients (omega-3 polyunsaturated fatty acids, dietary antioxidants, probiotics, and prebiotics) have the potential to modulate inflammatory and oxidative responses and, therefore, could be considered in the search for adverse complication prevention means as long as antineoplastic treatment efficiency is maintained. Future Directions: There is a need to better understand the relationship between cardiometabolic complications, OxS, inflammation and diet during pediatric cancer treatment, which represents the ultimate goal of this review. Antioxid. Redox Signal. 35, 293-318.

Expression of TCF3 in Wilms' tumor and its regulatory role in kidney tumor cell viability, migration and apoptosis in vitro

Wilms' tumor (WT) is a major type of kidney cancer in children; however, the therapeutic measures for control of tumor metastasis, recurrence and death for this type of cancer remain unsatisfactory. The present study aimed to verify the expression of T-cell factor 3 (TCF3) in WT, and to explore its role in regulating the viability, migration and apoptosis of kidney tumor cells. Tumor tissues were collected from 10 patients with WT, and adjacent tissues were collected as normal controls. The expression levels of TCF3 were detected in WT tissues and adjacent tissues by reverse transcription-quantitative PCR (RT-qPCR), western blotting and immunohistochemistry. In addition, TCF3 expression was silenced in G401 kidney tumor cells via small interfering RNA transfection. Cell viability, cell cycle progression and cell apoptosis were assessed using the MTT assay and flow cytometry; the migration and invasion of kidney tumor cells were examined using Transwell and wound-healing assays; and the expression levels of Wnt signaling pathway-related genes (Wnt1, β-catenin and c-myc) were detected by RT-qPCR and western blotting. The results revealed that the expression levels of TCF3 were high in WT tissues from patients. Silencing TCF3 expression in G401 kidney tumor cells in vitro significantly inhibited cell viability and migration, and promoted cell apoptosis. Moreover, silencing TCF3 expression in G401 cells inhibited the expression levels of Wnt signaling pathway-related genes. Overall, these data indicated that TCF3 may be involved in WT development through regulation of Wnt signaling pathways. The findings of the present study provide a novel potential marker for the treatment and prognostic evaluation of WT.

Prognostic Factors for Wilms Tumor Recurrence: A Review of the Literature

Simple Summary

A Wilms tumor is a childhood kidney tumor. In high-income countries, 90% of patients with this tumor survive. However, the tumor recurs in 15% of patients. It is important to identify the patients at risk of recurrence in order to adjust treatment in such a way that recurrence may potentially be prevented. However, we are currently unable to determine precisely which patients are at risk of recurrence. Therefore, we present an overview of factors that influence the risk of recurrence, also known as prognostic factors. These factors range from patient-, tumor- and treatment-related characteristics to geographic and socioeconomic factors. In addition to these factors, biological markers, such as genetic alterations, should be studied more intensively as these markers may be able to better identify patients at risk of tumor recurrence.

Abstract

In high-income countries, the overall survival of children with Wilms tumors (WT) is ~90%. However, overall, 15% of patients experience tumor recurrence. The adverse prognostic factors currently used for risk stratification (advanced stage, high risk histology, and combined loss of heterozygosity at 1p and 16q in chemotherapy-naïve WTs) are present in only one third of these cases, and the significance of these factors is prone to change with advancing knowledge and improved treatment regimens. Therefore, we present a comprehensive, updated overview of the published prognostic variables for WT recurrence, ranging from patient-, tumor- and treatment-related characteristics to geographic and socioeconomic factors. Improved first-line treatment regimens based on clinicopathological characteristics and advancing knowledge on copy number variations unveil the importance of further investigating the significance of biological markers for WT recurrence in international collaborations.

Synchronous bilateral Wilms' tumor with liver metastasis

Background

Wilms’ tumor (nephroblastoma) is mostly unilateral; however, bilateral Wilms’ tumors are seen in about 5–8% of patients. This can be synchronous or metachronous. It is uncommon to get liver metastasis from bilateral Wilms’ tumor.

Case presentation

An 8-year-old male Ugandan presented with a history of abdominal swelling and flank pains for 1 year. There was no history of hematuria. Both ultrasound and computed tomography of the abdomen demonstrated multiple solid lesions in both kidneys and a huge solid mass in segments V, VI, VII and VIII of the liver. Histological examination of renal biopsy specimen was favorable for chemotherapeutic regimens. However, following a multidisciplinary tumor board consensus, a nephron-sparing surgery was deemed unsuitable, and he was managed conservatively with chemotherapy (adriamycin and vincristine) with a palliative intent.

Conclusions

Metastatic bilateral Wilms’ tumor has a particularly poor prognosis. There are no clear evidence-based guidelines for the management of this rare presentation. This patient benefited from early palliative care and symptom management.

Relapsed Wilms' Tumor Presenting as Metastasis to the Zygoma

Wilms’ tumor accounts for the majority of renal tumors in children. Rarely, Wilms’ tumor may metastasize to the bone. We present a case of a 15-month-old female who presented with severe abdominal distension and signs of cachexia. Abdominal ultrasonography and radiography of the abdomen both demonstrated a large abdominal mass. Follow-up computed tomography of the abdomen revealed a heterogeneous intra-abdominal mass arising from the left kidney which was surrounded by a thin rim of renal parenchyma. Biopsy of the mass revealed findings consistent with Wilms’ tumor. The patient was 14 months status-post nephrectomy and chemoradiation but returned to the clinic with left facial swelling. Magnetic resonance imaging of the face demonstrated a multilobulated, heterogeneously enhancing solitary mass lesion in the left temple centered in the left zygoma with signs of bone breakdown. Despite its rarity, metastatic Wilms’ tumor to bone should be considered in a child presenting with a new focal mass overlying bony-structures.

Childhood Cancer: Occurrence, Treatment and Risk of Second Primary Malignancies

Cancer represents the leading cause of disease-related death and treatment-associated morbidity in children with an increasing trend in recent decades worldwide. Nevertheless, the 5-year survival of childhood cancer patients has been raised impressively to more than 80% during the past decades, primarily attributed to improved diagnostic technologies and multiagent cytotoxic regimens. This strong benefit of more efficient tumor control and prolonged survival is compromised by an increased risk of adverse and fatal late sequelae. Long-term survivors of pediatric tumors are at the utmost risk for non-carcinogenic late effects such as cardiomyopathies, neurotoxicity, or pneumopathies, as well as the development of secondary primary malignancies as the most detrimental consequence of genotoxic chemo- and radiotherapy. Promising approaches to reducing the risk of adverse late effects in childhood cancer survivors include high precision irradiation techniques like proton radiotherapy or non-genotoxic targeted therapies and immune-based treatments. However, to date, these therapies are rarely used to treat pediatric cancer patients and survival rates, as well as incidences of late effects, have changed little over the past two decades in this population. Here we provide an overview of the epidemiology and etiology of childhood cancers, current developments for their treatment, and therapy-related adverse late health consequences with a special focus on second primary malignancies.

Gene expression-based immune infiltration analyses of renal cancer and their associations with survival outcome

BACKGROUND

Renal cancer is a common malignant tumor with an increasing incidence rate.

METHODS

In this study, based on the gene expression profiles, we analyzed the compositions of tumor-infiltrating immune cells (TIICs) in renal cancer and paracancerous samples using CIBERSORT. The proportions of 22 TIICs subsets in 122 paired renal carcinoma and paracancerous samples, and 224 Wilms tumor (WT) samples varied between intragroup and intergroup.

RESULTS

After analyzed the difference of TIICs composition between renal cancer and paired paracancerous samples, we found that M0 macrophages and CD8 T cells were significantly elevated, while naive B cells were significantly decreased in renal cancer samples compared with paracancerous samples. Survival analysis showed that high overall TIICs proportion, the low proportion of resting mast cells and the high proportion of activated memory CD4 T cells were associated with poor prognosis of renal cancer patients. In addition, 3 clusters were identified by hierarchical clustering analysis, and they presented a distinct prognosis. Cluster 1 had superior survival outcomes, while cluster 2 had an inferior survival outcome.

CONCLUSIONS

Our study indicated that overall TIICs proportion, certain TIICs subset proportion, including resting mast cells and activated memory CD4 T cells, and distinct cluster patterns were associated with the prognosis of renal cancer, which was significant for the clinical surveillance and treatment of renal cancer.

MiR-200a with CDC7 as a direct target declines cell viability and promotes cell apoptosis in Wilm's tumor via Wnt/β-catenin signaling pathway

MiR-200a acts as a key role in tumor malignant progression. This work purposed to assess the function of miR-200a in Wilm's tumor. Based on bioinformatics analysis, the expression, prognostic value and related pathways of miR-200a and CDC7 (a potential downstream molecule of miR-200a) in Wilm's tumor were analyzed. qRT-PCR was conducted to confirm the miR-200a level in Wilm's tumor cells. The luciferase reporter assay was carried out to verify the binding of miR-200a to 3'-UTR of CDC7. Then, the impacts of miR-200a and CDC7 on cell viability and apoptosis were measured using CCK-8 and flow cytometry assays. Also, western blot was applied to measure the expression of CDC7 as well as Wnt/β-catenin signaling pathway-related proteins and apoptosis proteins. Herein, we revealed that miR-200a was lowly expressed in Wilm's tumor tissues and cells and the low miR-200a expression is closely bound up with death and poor outcomes. Moreover, miR-200a directly targeted and inhibited CDC7 in Wilm's tumor cells. Biological function experiments illustrated that overexpression of miR-200a reduced the viability and elevated the apoptosis of Wilm's tumor cells, while overexpression of CDC7 reversed the inhibitory impact of miR-200a on cell viability and the promoting impact of miR-200a on cell apoptosis. Besides, we revealed that miR-200a/CDC7 axis can decrease the expression of β-Catenin, Cyclin D1 and C-Myc as well as the phosphorylation of GSK-3β, thus inhibiting the Wnt/β-catenin signaling pathway. Furthermore, blocking the Wnt/β-catenin signaling pathway caused an increase on cell apoptosis, while overexpression of CDC7 can reverse these impacts. Collectively, miR-200a/CDC7 axis involved in regulating the malignant phenotype of Wilm's tumor through Wnt/β-catenin signaling pathway, which provides a theoretical basis for targeted molecular therapy of Wilm's tumor.

Comprehensive Analysis of a Long Noncoding RNA-Associated Competing Endogenous RNA Network in Wilms Tumor

Long noncoding RNA (lncRNA) plays crucial roles in various biological processes of different cancers, especially acting as a competing endogenous RNA (ceRNA). However, the role of lncRNA-mediated ceRNA in Wilms tumor (WT), which is the most common malignant kidney cancer in children, remains unknown. In present study, RNA sequence profiles and clinical data of 125 patients with WT consisting of 119 tumor and 6 normal tissues from Therapeutically Applicable Research To Generate Effective Treatments database were analyzed. A total of 1833 lncRNAs, 156 microRNAs (miRNAs), and 3443 messenger RNAs (mRNAs) were identified as differentially expressed (DE) using "DESeq2" package. The lncRNA-miRNA-mRNA ceRNA regulatory network involving 748 DElncRNAs, 33 DEmiRNAs, and 189 DEmRNAs was constructed based on miRcode, Targetscan, miRTarBase, and miRDB database. Gene Ontology term and Kyoto Encyclopedia of Genes and Genomes pathway analyses revealed that DEmRNAs were mainly enriched in cell proliferation-related processes and tumor-related pathways, respectively, and 13 hub genes were identified by a protein-protein interaction network. Survival analysis detected 48 lncRNAs, 7 miRNAs, and 16 mRNAs to have significant impact on the overall survival of patients with WT. Additionally, we found that 6 DElncRNAs with potential prognostic value were correlated with tumor stage (DENND5B-AS1) and histologic classification (TMPO-AS1, RP3-523K23.2, RP11-598F7.3, LAMP5-AS1, and AC013275.2) of patients with WT. Our research provides a great insight into understanding the molecular mechanism underlying occurrence and progression of WT, as well as the potential to develop targeted therapies and prognostic biomarkers.

Wilms' Tumor Primary Cells Display Potent Immunoregulatory Properties on NK Cells and Macrophages

The immune response plays a crucial defensive role in cancer growth and metastasis and is a promising target in different tumors. The role of the immune system in Wilm's Tumor (WT), a common pediatric renal malignancy, is still to be explored. The characterization of the immune environment in WT could allow the identification of new therapeutic strategies for targeting possible inhibitory mechanisms and/or lowering toxicity of the current treatments. In this study, we stabilized four WT primary cultures expressing either a blastematous (CD56+/CD133-) or an epithelial (CD56-/CD133+) phenotype and investigated their interactions with innate immune cells, namely NK cells and monocytes. We show that cytokine-activated NK cells efficiently kill WT cells. However, after co-culture with WT primary cells, NK cells displayed an impaired cytotoxic activity, decreased production of IFNγ and expression of CD107a, DNAM-1 and NKp30. Analysis of the effects of the interaction between WT cells and monocytes revealed their polarization towards alternatively activated macrophages (M2) that, in turn, further impaired NK cell functions. In conclusion, we show that both WT blastematous and epithelial components may contribute directly and indirectly to a tumor immunosuppressive microenvironment that is likely to play a role in tumor progression.