Wilms tumor: an update

Modification of Polyethylene Glycol-Hydroxypropyl Methacrylate Polymeric Micelles Loaded with Curcumin for Cellular Internalization and Cytotoxicity to Wilms Tumor 1-Expressing Myeloblastic Leukemia K562 Cells

Curcumin loaded in micelles of block copolymers of ω-methoxypoly(ethylene glycol) and N-(2-hydroxypropyl) methacrylamide modified with aliphatic dilactate (CD) or aromatic benzoyl group (CN) were previously reported to inhibit human ovarian carcinoma (OVCAR-3), human colorectal adenocarcinoma (Caco-2), and human lymphoblastic leukemia (Molt-4) cells. Myeloblastic leukemia cells (K562) are prone to drug resistance and differ in both cancer genotype and phenotype from the three mentioned cancer cells. In the present study, CD and CN micelles were prepared and their effects on K562 and normal cells were explored. The obtained CD and CN showed a narrow size distribution with diameters of 63 ± 3 and 50 ± 1 nm, respectively. The curcumin entrapment efficiency of CD and CN was similarly high, above 80% (84 ± 8% and 91 ± 3%). Both CD and CN showed suppression on WT1-expressing K562 and high cell-cycle arrest at the G2/M phase. However, CD showed significantly higher cytotoxicity to K562, with faster cellular uptake and internalization than CN. In addition, CD showed better compatibility with normal red blood cells and peripheral blood mononuclear cells than CN. The promising CD will be further investigated in rodents and possibly in clinical studies for leukemia treatment.

Single-cell transcriptomes of kidneys in a 6-month-old boy with Denys-Drash syndrome reveal stromal cell heterogeneity in the tumor microenvironment

Background

Denys-Drash syndrome (DDS) is a rare disease characterized with pseudohermaphroditism, nephroblastoma (also known as Wilms tumor), and diffuse mesangial sclerosis. The therapy for DDS is largely supportive, i.e. surgery and chemotherapy for Wilms tumor and renal replacement therapy. Due to the limited understanding of the pathogenesis, precision therapy for DDS is yet to be explored. We sought to explore the cellular components and interactions in kidney tissues from an infant with DDS.

Methods

Whole-exome sequencing was performed to examine the mutations associated with DDS. Single-cell RNA sequencing (scRNA-seq) was performed to explore the heterogenicity of kidney tissue samples.

Results

A 6-month-old infant with bilateral Wilms tumors and genital ambiguity was diagnosed as having DDS. Whole exome sequencing revealed a novel de novo mutation (p.F185fs*118) in exon 1 of WT1. scRNA-seq was performed in tissue samples from bilateral Wilms tumors and the normal kidney from this infant. Fibroblasts, myocytes, epithelial cells, endothelial cells, and mononuclear phagocytes (MPs) ranked at the top of the 31 135 total cells. Fibroblasts and myocytes were dominant in the Wilms tumor samples. In contrast, most epithelial cells and endothelial cells were found in normal kidney tissues. CD44 and TUBA1A were significantly changed in myocyte subclusters, which may contribute to chemotherapy drug resistance. Macrophages intensively interacted with cancerous cells, including fibroblasts, epithelial cells, and myocytes.

Conclusions

A novel mutation (p.F185fs*118) in exon 1 of WT1 was identified in an infant with DDS. scRNA-Seq revealed the heterogenicity of cellular components in Wilms tumors and kidney tissues, shedding light on the pathogenesis of DDS.

Immunohistochemical expression of P53 protein in nephroblastoma: a predictor of unfavorable prognosis

OBJECTIVE

Immunohistochemical expression of P53 protein is so closely related to status of mutation of P53 gene which is tightly linked with pathogenesis of nephroblastoma or Wilms tumor. This study aims to determine the immunohistochemical expression of P53 protein and its predictors in formalin-fixed paraffin-embedded tissue blocks of patients with nephroblastoma.

MATERIALS AND METHODS

A series of 83 histologically diagnosed cases of nephroblastoma from formalin-fixed paraffin-embedded tissue blocks archived at the Department of Pathology, Makerere University, in Kampala, Uganda, were analyzed. Monoclonal anti-p53 antibody (DO-7, DAKO) was used to assess the expression of P53 protein expression. Multivariable logistic regression analysis was performed to determine the predictors of P53 protein immunohistochemical expression, and statistical significance was considered when p-value was less than 0.05.

RESULTS

Most (42.2%, n = 35) of the cases were in advanced tumor stages (III-V), and almost one-quarter (21.7%, n = 18) of the cases were in high-risk group. The immunohistochemical expression of P53 protein was (8.4%, n = 7), and there were more (83.3%, n = 5) positive anaplastic cases for P53 protein compared with (2.6%, n = 2) of P53 expression for non-anaplastic cases. High risk (AOR = 3.42, 95% CI = 7.91-12.55, p = 0.037) and anaplasia (AOR = 1.41, 95% CI = 13.85-4.46, p = 0.001) were potential predictors of immunohistochemical expression of P53 protein.

CONCLUSION

Most of patients with nephroblastoma in resources-limited settings are diagnosed with advanced clinical stages. Association of P53 protein with anaplasia found in this study indicates the possibility of having novel target therapy for treatment of patients with anaplastic form of nephroblastoma with a focus of identifying molecules that lead to its suppression in such subpopulations of patients with nephroblastoma.

Somatic, Genetic and Epigenetic Changes in Nephrogenic Rests and Their Role in the Transformation to Wilms Tumors, a Systematic Review

OBJECTIVE

To review somatic genetic changes in nephrogenic rests (NR), which are considered to be precursor lesions of Wilms tumors (WT).

METHODS

This systematic review is written according to the PRISMA statement. PubMed and EMBASE were systematically searched for articles in the English language studying somatic genetic changes in NR between 1990 and 2022.

RESULTS

Twenty-three studies were included in this review, describing 221 NR of which 119 were pairs of NR and WT. Single gene studies showed mutations in WT1 and WTX, but not CTNNB1 to occur in both NR and WT. Studies investigating chromosomal changes showed loss of heterozygosity of 11p13 and 11p15 to occur in both NR and WT, but loss of 7p and 16q occurred in WT only. Methylome-based studies found differential methylation patterns between NR, WT, and normal kidney (NK).

CONCLUSIONS

Over a 30-year time frame, few studies have addressed genetic changes in NR, likely hampered by technical and practical limitations. A limited number of genes and chromosomal regions have been implicated in the early pathogenesis of WT, exemplified by their occurrence in NR, including WT1, WTX, and genes located at 11p15. Further studies of NR and corresponding WT are urgently needed.

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.

Advances in the treatment of pediatric solid tumors: A 50-year perspective

In the United States, more than 10 000 cancers occur annually in children aged 0-14 years, and more than 5000 in adolescents aged 15-19. In the last 50 years, significant advances have been made in imaging, molecular pathology, stage and risk assessment, surgical approach, multidisciplinary treatment, and survival for pediatric solid tumors (particularly neuroblastoma, Wilms tumor, rhabdomyosarcoma, and hepatoblastoma). Moreover, the molecular driver for fibrolamellar hepatocellular carcinoma, which occurs in adolescence and young adulthood, has been identified.

FOXO3a‑modulated DEPDC1 promotes malignant progression of nephroblastoma via the Wnt/β‑catenin signaling pathway

DEP domain containing 1 (DEPDC1) and forkhead box transcription factor 3a (FOXO3a) serve a role in tumor cells. To the best of our knowledge, however, the expression of DEPDC1 and FOXO3a in nephroblastoma and their role and potential mechanisms in nephroblastoma cells have not been reported. The aim of the present study was to characterize the expression of DEPDC1 and FOXO3a in nephroblastoma, as well as the underlying mechanisms. The expression levels of DEPDC1 and FOXO3a were detected using reverse transcription-quantitative PCR and western blotting. Cell viability, proliferation, invasion and migration were detected using Cell Counting Kit-8, colony formation, Transwell and wound healing assays, respectively. The activity of DEPDC1 promoter was detected by dual-luciferase reporter assay and the association between FOXO3a and DEPDC1 was detected using immunoprecipitation. DEPDC1 expression was significantly increased in nephroblastoma cells, particularly WiT49 cells. Compared with the negative control, DEPDC1 knockdown significantly inhibited proliferation, invasion and migration of WiT49 cells, while DEPDC1 overexpression (Ov) reversed these effects. By contrast, expression of FOXO3a was decreased in WiT49 cells and immunoprecipitation showed that FOXO3a bound to the DEPDC1 promoter. Ov-FOXO3a inhibited WiT49 cell proliferation, invasion and migration, as well as protein expression levels of phosphorylated-glycogen synthase kinase-3β, Wnt3a and β-catenin, while DEPDC1 Ov reversed the inhibitory effects of FOXO3a Ov on WiT49 cells. In conclusion, DEPDC1 promoted malignant progression of nephroblastoma via the Wnt/β-catenin signaling pathway; this may be regulated by FOXO3a.

Characterization of Associated Nonclassical Phenotypes in Patients with Deletion in the WAGR Region Identified by Chromosomal Microarray: New Insights and Literature Review

WAGR syndrome (Wilms' tumor, aniridia, genitourinary changes, and intellectual disability) is a contiguous gene deletion syndrome characterized by the joint deletion of PAX6 and WT1 genes, located in the short arm of chromosome 11. However, most deletions include other genes, leading to multiple associated phenotypes. Therefore, understanding how genes deleted together can contribute to other clinical phenotypes is still considered a challenge. In order to establish genotype-phenotype correlation in patients with interstitial deletions of the short arm of chromosome 11, we selected 17 patients with deletions identified by chromosomal microarray analysis: 4 new subjects and 13 subjects previously described in the literature with detailed clinical data. Through the analysis of deleted regions and the phenotypic changes, it was possible to suggest the contribution of specific genes to several nonclassical phenotypes, contributing to the accuracy of clinical characterization of the syndrome and emphasizing the broad phenotypic spectrum found in the patients. This study reports the first patient with a PAX6 partial deletion who does not present any eye anomaly thus opening a new set of questions about the functional activity of PAX6.

Evaluating Established Roles, Future Perspectives and Methodological Heterogeneity for Wilms’ Tumor 1 (WT1) Antigen Detection in Adult Renal Cell Carcinoma, Using a Novel N-Terminus Targeted Antibody (Clone WT49)

Renal cell carcinoma (RCC) is arguably the deadliest form of genitourinary malignancy and is nowadays viewed as a heterogeneous series of cancers, with the same origin but fundamentally different metabolisms and clinical behaviors. Immunohistochemistry (IHC) is increasingly necessary for RCC subtyping and definitive diagnosis. WT1 is a complex gene involved in carcinogenesis. To address reporting heterogeneity and WT1 IHC standardization, we used a recent N-terminus targeted monoclonal antibody (clone WT49) to evaluate WT1 protein expression in 56 adult RCC (aRCC) cases. This is the largest WT1 IHC investigation focusing exclusively on aRCCs and the first report on clone WT49 staining in aRCCs. We found seven (12.5%) positive cases, all clear cell RCCs, showing exclusively nuclear staining for WT1. We did not disregard cytoplasmic staining in any of the negative cases. Extratumoral fibroblasts, connecting tubules and intratumoral endothelial cells showed the same exclusively nuclear WT1 staining pattern. We reviewed WT1 expression patterns in aRCCs and the possible explanatory underlying metabolomics. For now, WT1 protein expression in aRCCs is insufficiently investigated, with significant discrepancies in the little data reported. Emerging WT1-targeted RCC immunotherapy will require adequate case selection and sustained efforts to standardize the quantification of tumor-associated antigens for aRCC and its many subtypes.

Knockdown of lncRNA HAGLROS inhibits metastasis and promotes apoptosis in nephroblastoma cells by inhibition of autophagy

Nephroblastoma, or Wilms tumor, is a primary renal malignant tumor that easily occurs in children. Previous studies have revealed the regulatory functions of LncRNA in nephroblastoma. LncRNA HAGLROS functions as a tumor promotor in various cancers including hepatocellular carcinoma, ovarian cancer and colorectal cancer. In this study, the HAGLROS expression in nephroblastoma cells was assayed through qRT-PCR. Cell proliferation assessment employed CCK-8. Moreover, the migration and invasion of cells were examined separately through wound healing and transwell assay. Moreover, flow cytometric analysis and Western blot assay were applied to evaluate cell apoptosis. Rapamycin and 3-methyladenine were used to serve as autophagy activator or inhibitor, respectively. In addition, autophagy was identified by immunofluorescence staining and Western blot analysis. Experiment results showed that HAGLROS expressed highly in nephroblastoma cell lines. HAGLROS knockdown prevented cells from proliferating, and also showed suppressive impact on migration and invasion in HFWT cells. In addition, knockdown of HAGLROS showed a facilitative effect on apoptosis and an inhibitory effect on autophagy. Stimulation of autophagy alleviated HAGLROS silencing-induced apoptosis, while inhibition of autophagy reversed the effect in nephroblastoma cells. In summary, our results revealed that HAGLROS executed an oncogenic role in the progress of nephroblastoma, offering a new perspective on the strategy for nephroblastoma therapy.

PDGF-BB/PDGFRβ Promotes Epithelial-Mesenchymal Transition by Affecting PI3K/AKT/mTOR-Driven Aerobic Glycolysis in Wilms' tumor G401 Cells

Wilms' tumor (WT) is the most common pediatric renal malignancy. PDGFRβ belongs to the type III receptor tyrosine kinase family and is known to be involved in tumor metastasis and angiogenesis. Here, we studied the effect and underlying mechanism of PDGFRβ on Wilms' tumor G401 cells. Transwell assay and wound-healing assay were used to detect the effect of PDGFRβ on G401 cells invasion and migration. Western blot and immunofluorescence were used to detect the expression of EMT-related genes. The expression of PI3K/AKT/mTOR pathway proteins was detected by western blot. The relationship between PDGFRβ and aerobic glycolysis was studied by assessing the expression of glycolysis-related enzymes detected by qRT-PCR and western blot. The activity of HK, PK and LDH was detected by corresponding enzyme activity kits. The concentration of lactic acid and glucose was detected by Lactic Acid Assay Kit and Glucose Assay Kit-glucose oxidase method separately. To investigate the mechanism of PDGFRβ in the development of Wilms' tumor, the changes of glucose and lactic acid were analyzed after blocking PI3K pathway, aerobic glycolysis or PDGFRβ. The key enzyme was screened by western blot and glucose metabolism experiment after HK2, PKM2 and PDK1 were inhibited. The results showed that PDGFRβ promoted the EMT process by modulating aerobic glycolysis through PI3K/AKT/mTOR pathway in which PKM2 plays a key role. Therefore, our study of the mechanism of PDGFRβ in G401 cells provides a new target for the treatment of Wilms' tumor. This article is protected by copyright. All rights reserved.

MMP-9 secreted by M2-type macrophages promotes Wilms' tumour metastasis through the PI3K/AKT pathway

BACKGROUND

Wilms' tumour (WT) is a malignant tumour of childhood with the typical symptoms of an abdominal mass. Tumour-associated macrophages (TAMs) accumulate and imply a poor prognosis in WT, but the mechanism of how TAMs affect the prognosis has not been fully elucidated. In this study, we aimed to present the molecular mechanisms underlying the protumorigenic capacities of TAMs in WT.

METHODS

TAMs were polarized into M1- and M2-type macrophages. The two types of macrophages were cocultured with SK-NEP-1 cells, and their cell viability and invasion ability were measured. Matrix metalloproteinase 9 (MMP9) expression was assessed in different types of macrophages, and the role of MMP9 in WT was explored. Then data from children diagnosed with WT in our department between February 2006 and July 2014 were retrospectively analysed, the tumour tissues were analysed to explore the distribution of MMP9. Kaplan-Meier analysis of the relationship between MMP9 expression and follow-up information was performed.

RESULTS

The results showed that M2-type macrophages could improve the viability and invasive ability of SK-NEP-1 cells. MMP9 expression in M2-type macrophages was significantly higher than that in M1-type macrophages. MMP9 could activate the AKT/PI3K signalling pathway to initiate the epithelial-mesenchymal transition (EMT) process, and promote the proliferation and invasion of WT. In WT tissue, the MMP9 expression level was elevated and it was located in the tumour stroma, which was the same as M2-type macrophage location, and a high level of MMP9 predicted poor survival.

CONCLUSION

M2-type macrophages facilitate tumour proliferation and metastasis by secreting MMP9 to enhance the EMT process via a PI3K/AKT dependent pathway in Wilms' tumour.

Teratoid Wilms Tumor and Classical Wilms Tumor: A Retrospective 10-Year Single-Center Study and Literature Review

Background

One of the most prevalent forms of renal tumors detected among pediatric patients is the Wilms tumor (WT). Teratoid WT is a rare WT subclassification that is characterized by teratoma-like characteristics that include the features of many diverse tissue categories. Less than 70 teratoid Wilms tumor (TWT) cases have been explained up to now.

Methods

Between 2010 and 2020, patients with classical WT and TWT admitted to our hospital were included in this study. Clinicopathological characteristics, intraoperative findings, histopathological parameters, and prognostic outcomes were then compared between classical WT and TWT. To compare these variables, TWT and WT cases were matched at a 1:3 ratio.

Results

A total of 67 total WT cases, i.e., five diagnosed with TWT, were enrolled. While no significant differences in analyzed variables were detected between these groups, tumor volumes were notably larger in the TWT group relative to the classical WT group (203.30 ± 109.89 vs. 104.30 ± 66.97 cm3) despite similar tumor weight values in both groups (471.00 ± 80.65 vs. 432.67 ± 109.25 g). As for five patients diagnosed with TWT, all were alive during the follow-up, while one of them was diagnosed with pelvic metastasis.

Conclusions

This study is the first to our knowledge to have reported on the incidence of TWT among Chinese children, and our results preliminarily suggest that a combination of surgery and chemotherapy may be appropriate for the treatment of patients with WT, although prognostic outcomes varied substantially among patients with different stages of the disease. TWT tumor density may be lower than classical WT tumor density. Further research regarding the basic biological characteristics of TWT and relevant theranostic markers associated with this tumor type is warranted to better guide the development of individualized treatments for this rare cancer type.

Roles of hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunit alpha, a lipid metabolism enzyme, in Wilms tumor patients

Objectives

Wilms tumor is a common pediatric malignant tumor that accounts for approximately 95% of kidney tumors in children. The role of lipid metabolism in tumors has attracted increased attention in recent years. We examined the role of hydroxyacyl-CoA dehydrogenase trifunctional multienzyme complex subunit alpha (HADHA), a lipid metabolism enzyme, in the pathogenesis of Wilms tumor.

Materials and Methods

In a previous study, we screened Wilms tumors and adjacent normal tissues for differentially expressed proteins by mass spectrometry and verified the results by western blot analysis. The Oncomine database and quantitative reverse transcription-polymerase chain reaction were used to verify the expression of HADHA at the genetic level. Immunohistochemistry and immunofluorescence were also used to validate the differential expression of the HADHA protein. The relationship between histopathological typing, clinical pathology, and HADHA expression was analyzed in 65 paraffin-embedded specimens from pediatric Wilms tumor patients. Kaplan-Meier survival curves were used to analyze the relationship between the expression of HADHA and patient prognosis.

Results

HADHA was expressed at low levels in Wilms tumor tissue compared with the corresponding normal tissue. The expression of HADHA was closely associated with histopathological typing (P = 0.030). The prognostic analysis of 65 children with Wilms tumor showed that high expression of HADHA was closely associated with poor prognosis (P = 0.046).

Conclusions

HADHA expression is downregulated in Wilms tumor tissues, but high expression in tumor tissues is associated with clinical stage and the prognosis of children with this tumor.

Silencing of lncRNA MEG8 Represses the Viability, Migration, and Invasion of Wilms' Tumor Cells through Mediating miR-23a-3p/CRK Axis

PURPOSE

Compelling evidence has unveiled the importance of long noncoding RNAs (lncRNAs) in malignant behavior of Wilms' tumor (WT). Hereon, we intend to assess the function and associated molecular mechanism of lncRNA maternally expressed gene 8 (MEG8) in WT cells.

METHODS

Expression levels of MEG8, miR-23a-3p, and CT10 regulator of kinase (CRK) were determined by quantitative real-time polymerase chain reaction. Cell viability was assessed by MTT assay. Besides, wound healing assay and transwell assay were applied to examine abilities of cell migration and invasion, respectively. Dual-luciferase reporter assay was employed to test the interplay among MEG8, miR-23a-3p, and CRK. Western blot was used to detect relative protein expression of CRK.

RESULTS

MEG8 and CRK expression was elevated, while miR-23a-3p expression was decreased in WT tissues and cells. The histologic type, lymphatic metastasis, and National Wilms Tumor Study (NWTS) stage were associated with the expression of MEG8, miR-23a-3p, and CRK in WT patients. MEG8 knockdown or miR-23a-3p overexpression restrained WT cells in cell viability, migration, and invasiveness in vitro. As to mechanism exploration, MEG8 could directly bind to miR-23a-3p and then miR-23a-3p targeted CRK. MEG8 was inversely correlated with miR-23a-3p and positively correlated with CRK in WT tissues. Meantime, miR-23a-3p was inversely correlated with CRK in WT tissues. Additionally, MEG8 knockdown-mediated suppressive impacts on cell viability, migration, and invasiveness were reversed by overexpression of CRK or repression of miR-23a-3p in WT cells.

CONCLUSIONS

The cell viability, migration, and invasiveness of WT cells were repressed by MEG8 knockdown via targeting the miR-23a-3p/CRK axis.

A Spontaneously Necrotic Wilms' Tumor Mimicking Renal Abscess: A Tricky Diagnosis not to Miss

Wilms' tumor (WT) is the most common renal malignancy in children. Its clinical and radiologic presentation may mimic other pediatric renal diseases, including pyonephrosis or renal abscess. The authors report a case of a 3-year-old girl presenting with pyelonephritis and right renal mass suggestive of a renal abscess, not responding to antibiotics. Further investigations were conducted, including a percutaneous renal needle core biopsy. A stage I fully necrotic WT was finally diagnosed. This amazing case of a fully necrotic WT at diagnosis demonstrates the importance of anatomopathologic analyses in pediatric renal masses, even when the infection is suspected.

A Survival-Related Competitive Endogenous RNA Network of Prognostic lncRNAs, miRNAs, and mRNAs in Wilms Tumor

Wilms tumor (WT) commonly occurs in infants and children. We evaluated clinical factors and the expression of multiple RNAs in WT samples in the TARGET database. Eight long non-coding RNAs (lncRNAs; AC079310.1, MYCNOS, LINC00271, AL445228.3, Z84485.1, AC091180.5, AP002518.2, and AC007879.3), two microRNAs (miRNAs; hsa-mir-152 andhsa-mir-181a), and nine messenger RNAs (mRNAs; TCTEX1D4, RNF133, VRK1, CCNE1, HEY1, C10orf71, SPRY1, SPAG11A, and MAGEB18) were screened from differentially expressed RNAs and used to construct predictive survival models. These models showed good prognostic ability and were highly correlated with tumor stage and histological classification. Additionally, survival-related ceRNA network was constructed using 35 RNAs (15 lncRNAs, eight miRNAs, and 12 mRNAs). KEGG pathway analysis suggested the "Wnt signaling pathway" and "Cellular senescence" as the main pathways. In conclusion, we established a multinomial predictive survival model and a survival-related ceRNA network, which provide new potential biomarkers that may improve the prognosis and treatment of WT patients.

HOXB2 and FOXC1 synergistically drive the progression of Wilms tumor

OBJECTIVE

To uncover the expression patterns of HOXB2 and FOXC1 in Wilms tumor samples, and their synergistical regulations on the development of Wilms tumor.

METHODS

Expression levels of HOXB2 and FOXC1 in 58 cases of Wilms tumor tissues and paracancerous ones were detected. The influences of HOXB2 and FOXC1 on prognosis in Wilms tumor patients were analyzed. Their regulatory effects on proliferative and migratory abilities in WT-CLS1 and HFWT cells were examined by cell counting kit-8 (CCK-8) and Transwell assay, respectively. The interaction between HOXB2 and FOXC1, and their synergistical regulation on the development of Wilms tumor were finally explored.

RESULTS

HOXB2 and FOXC1 were upregulated in Wilms tumor tissues. Higher levels of HOXB2 and FOXC1 indicated higher risks of advanced stage and lymphatic metastasis, as well as worse prognosis in Wilms tumor patients. Knockdown of HOXB2 or FOXC1 weakened proliferative and migratory abilities in WT-CLS1 and HFWT cells, while the opposite trends were observed in those overexpressing HOXB2 or FOXC1. The positive interaction between HOXB2 and FOXC1 was identified, which synergistically drove the malignant development of Wilms tumor.

CONCLUSIONS

HOXB2 and FOXC1 are upregulated in Wilms tumor samples, and they are closely linked to tumor staging and lymphatic metastasis in Wilms tumor patients. HOXB2 and FOXC1 synergistically drive the malignant development of Wilms tumor by stimulating proliferative and migratory potentials.

Methylation Statuses of H19DMR and KvDMR at WT2 in Wilms Tumors in Taiwan

Wilms tumor is the most common pediatric renal malignancy. Several genetic loci have been shown to be associated with its formation. Genetic or epigenetic aberrations at WT1 and WT2 loci have been implicated in the etiology of the majority of sporadic Wilms tumors. In our previous study, most Wilms tumors tested negative for both constitutional mutations and somatic mutations in the WT1 gene. Thus, WT2 may play an important role in these tumors. In the present study, we analyzed the methylation statuses of WT2 at 11p15 using methylation sensitive multiplex ligation-dependent probe amplification in six Wilms tumors. Paternal uniparental disomy at WT2 was observed in two Wilms tumors with epithelial components due to hypermethylation at H19DMR and hypomethylation at KvDMR. Our findings highlight the benefits of testing for 11p15 epigenetic abnormalities to identify Wilms tumors with epithelial components.

Immunohistochemical Expression of Wilms’ Tumor 1 Protein in Human Tissues: From Ontogenesis to Neoplastic Tissues

The human Wilms’ tumor gene (WT1) was originally isolated in a Wilms’ tumor of the kidney as a tumor suppressor gene. Numerous isoforms of WT1, by combination of alternative translational start sites, alternative RNA splicing and RNA editing, have been well documented. During human ontogenesis, according to the antibodies used, anti-C or N-terminus WT1 protein, nuclear expression can be frequently obtained in numerous tissues, including metanephric and mesonephric glomeruli, and mesothelial and sub-mesothelial cells, while cytoplasmic staining is usually found in developing smooth and skeletal cells, myocardium, glial cells, neuroblasts, adrenal cortical cells and the endothelial cells of blood vessels. WT1 has been originally described as a tumor suppressor gene in renal Wilms’ tumor, but more recent studies emphasized its potential oncogenic role in several neoplasia with a variable immunostaining pattern that can be exclusively nuclear, cytoplasmic or both, according to the antibodies used (anti-C or N-terminus WT1 protein). With the present review we focus on the immunohistochemical expression of WT1 in some tumors, emphasizing its potential diagnostic role and usefulness in differential diagnosis. In addition, we analyze the WT1 protein expression profile in human embryonal/fetal tissues in order to suggest a possible role in the development of organs and tissues and to establish whether expression in some tumors replicates that observed during the development of tissues from which these tumors arise.

Telomere Maintenance in Pediatric Cancer

Telomere length has been proposed as a biomarker of biological age and a risk factor for age-related diseases and cancer. Substantial progress has been made in recent decades in understanding the complex molecular relationships in this research field. However, the majority of telomere studies have been conducted in adults. The data on telomere dynamics in pediatric cancers is limited, and interpretation can be challenging, especially in cases where results are contrasting to those in adult entities. This review describes recent advances in the molecular characterization of structure and function of telomeres, regulation of telomerase activity in cancer pathogenesis in general, and highlights the key advances that have expanded our views on telomere biology in pediatric cancer, with special emphasis on the central role of telomere maintenance in neuroblastoma. Furthermore, open questions in the field of telomere maintenance research are discussed in the context of recently published literature.

Identification of key genes and microRNAs involved in kidney Wilms tumor by integrated bioinformatics analysis

Wilms tumor (WT) is one of the most common types of pediatric solid tumors; however, its molecular mechanisms remain unclear. The present study aimed to identify key genes and microRNAs (miRNAs), and to predict the underlying molecular mechanisms of WT using integrated bioinformatics analysis. Original gene expression profiles were downloaded from the Gene Expression Omnibus (GEO; accession, GSE66405) and The Cancer Genome Atlas (TCGA) databases. Similarly, miRNA expression patterns were downloaded from GEO (accession, GSE57370) and TCGA. R version 3.5.0 software was used to identify differentially expressed genes (DEGs) and differentially expressed miRNAs (DEMs) using the limma and edgeR packages. Kyoto Encyclopedia of Genes and Genomes pathway and Gene Ontology analyses were performed to examine the biological functions of the DEGs. Additionally, a protein-protein interaction (PPI) network was constructed to screen hub gene modules using Cytoscape software. By predicting target genes of the DEMs and integrating them with DEGs, the present study constructed a miRNA-mRNA regulatory network to predict the possible molecular mechanism of WT. Expression of hub genes was validated using the Oncomine database. A total of 613 genes and 29 miRNAs were identified to be differentially expressed in WT. By constructing a PPI network and screening hub gene modules, 5 upregulated genes, including BUB1 mitotic checkpoint serine/threonine kinase, BUB1B mitotic checkpoint serine/threonine kinase B, cell division cycle protein 45, cyclin B2 and pituitary tumor-transforming 1. These genes were identified to be associated with the cell cycle pathway, which suggested that these genes may serve important roles in WT. In addition, a miRNA-mRNA regulatory network was constructed and comprised 16 DEMs and 19 DEGs. In conclusion, key genes, miRNAs and the mRNA-miRNA regulatory network identified in the present study may improve understanding of the underlying molecular mechanisms in the occurrence and development of WT, and may aid the identification of potential biomarkers and therapeutic targets.

High-Risk Adult Wilms' Tumour in Pregnancy: A Case Report

Wilms' tumour is the most common renal neoplasm in children with an incidence of 10 cases per 1 million children and a median age at diagnosis of 3.5 years. In Western countries its occurrence in adults is 0.2 cases per million people in western countries and carries a poorer prognosis. The co-existence of Adult Wilms' tumour and pregnancy is extremely rare with less than 20 cases published in the English literature. We present a case of a Malawian woman who had progressive high-risk metastatic Adult Wilms' tumour in pregnancy after nephrectomy, radiotherapy and two lines of chemotherapy.

Expression and clinical significance of p73 in Wilms tumor in children

Expression and clinical significance of p73 in children with Wilms tumor (WT) were investigated. A retrospective analysis was carried out on 50 children diagnosed with WT in the People's Hospital of Rizhao, from July 2013 to January 2015 (study group), and 20 healthy children with similar age and sex who received health examinations in the same hospital during the same period (control group). The relative expression of p73 mRNA in the peripheral blood of each group was detected by reverse transcription-quantitative PCR (RT-qPCR) in order to study the association between p73 and the clinicopathological parameters of WT, as well as the impact of p73 on the patient prognosis. The two groups were not statistically different in respect to the clinical data of patients (P>0.05); the expression level of p73 in the blood samples of the study group was significantly higher than that of the control group (t=11.44, P<0.01); the expression of p73 in the study group was associated with factors, including tumor size, pathological type and lymphatic metastasis. Considering the mean value of the expression of p73 (3.32) as the boundary, the patients with expression value of p73 <3.32 were studied as the low-expression group, and patients with expression value of p73 >3.32 comprised the high-expression group. At the end of the follow-up, the median survival time and the survival rate of the patients in the high-expression group were significantly lower than those of the low-expression group (P<0.05). The high expression of p73 in the peripheral blood of children with WT was positively correlated with the clinical stage of the tumor, and was closely related with the low survival rate of patients.

FXR1 expression domain in Wilms tumor

BACKGROUND/PURPOSE

Wilms tumor (WT) is the most common childhood kidney cancer globally. Our prior unbiased proteomic screen of WT disparities revealed increased expression of Fragile X-Related 1 (FXR1) in Kenyan specimens where survival is dismal. FXR1 is an RNA-binding protein that associates with poor outcomes in multiple adult cancers. The aim of this study therefore was to validate and characterize the FXR1 expression domain in WT.

METHODS

Quantitative FXR1 gene expression was compared between WT, adjacent, adult, and fetal kidney specimens. The cellular and subcellular expression domain of FXR1 was characterized across these tissues using immunoperoxidase staining. RNA-sequencing of FXR1 was performed from WT and other pediatric malignancies to examine its broader target potential.

RESULTS

FXR1 was detected in all clinical WT specimens evaluated (n = 82), and as a result appeared independent of demographic, histology, or adverse event. Specific cytosolic staining was strongest in blastema, intermediate and variable in epithelia, and weakest in stroma. When present, areas of skeletal muscle differentiation stained strongly for FXR1. qPCR revealed increased FXR1 expression in WT compared to adult and adjacent kidney (p < 0.0002) but was similar to fetal kidney (p = 0.648). RNA-sequencing revealed expression of FXR1 in multiple pediatric tumors, greatest in rhabdomyosarcoma and WT.

CONCLUSIONS

FXR1 was expressed consistently across this broad sampling of WT and most robustly in the primitive blastema. Notably, FXR1 labeled a specific self-renewing progenitor population of the fetal kidney.

SOX21-AS1 is associated with clinical stage and regulates cell proliferation in nephroblastoma

LncRNA SOX21 antisense RNA 1 (SOX21-AS1) dysregulated in many types of human cancer, and functioned as tumor suppressor or promoter depending on tumor types. However, there was no report about the role of SOX21-AS1 in nephroblastoma. In the present study, we first found that SOX21-AS1 expression was elevated in nephroblastoma tissues and cell lines compared with adjacent normal tissues and normal human embryonic kidney cell line, respectively. Moreover, we observed nephroblastoma patients with large tumor size, advanced National Wilms Tumor Study (NWTS) stage or unfavorable histopathological type, and patients that had higher SOX21-AS1 expression levels than nephroblastoma patients with small tumor size, early NWTS stage or favorable histopathological type. The in vitro studies suggested that knockdown of SOX21-AS1 suppressed nephroblastoma cell proliferation and colony formation, and induced cell-cycle arrest through up-regulating p57 expression. In conclusion, our study suggests that SOX21-AS1 functions as oncogenic lncRNA in nephroblastoma, which may provide a novel insight for nephroblastoma carcinogenesis.

Expression of YY1 in Wilms tumors with favorable histology is a risk factor for adverse outcomes

Aim: To investigate the role of the transcription factor YY1 in Wilms tumor (WT). Patients & methods: We measured YY1 expression using tissue microarray from patients with pediatric renal tumors, mainly WT and evaluated correlations with the predicted clinical evolution. YY1 expression was measured using immunohistochemical and protein expression was determined by digital pathology. Results & conclusion: YY1 significantly increased in WT patients. In addition, an increase in YY1 expression had a greater risk of adverse outcomes in WT patients with favorable histology. YY1 expression was higher in the blastemal component of tumors, and high nuclear expression positively correlated with metastasis. YY1 may be considered as a metastasis risk factor in WT.

Investigating the dysfunctional pathogenesis of Wilms' tumor through a multidimensional integration strategy

Background

Wilms' tumor (WT) is a common kidney tumor in early childhood which is characterized by multiple congenital anomalies and syndromes. With the continuous improvement of medical standards, the cure rate and survival period of WT have increased. However, its molecular mechanism is still elusive.

Methods

A comprehensive multidimensional integration strategy was used to comprehensively analyze the mechanisms of WT.

Results

By integrating the potential pathogenic genes of kidney cancer and performing co-expression analysis on the disease-related genes, 23 functional modules were obtained. All the genes were differentially expressed in WT, and were mainly involved in many biological processes and signaling pathways, such as Wnt/β-catenin, mTOR/ERK and calcineurin. Additionally, based on the relationship between transcriptional and post-transcriptional regulatory systems, in functional modules, transcription factors (TFs) including STAT3, HDAC1 and SP1 as well as non-coding RNAs (ncRNAs) such as miR-335-5p, miR-21-5p and TUG1 were identified. Finally, potential drugs for these multifactor regulated dysfunctional modules which may have certain pharmacological or toxicological effects on WT such as cisplatin, sorafenib, and zinc were predicted.

Conclusions

A multidimensional dysfunction mechanism, involving disease-related genes, TFs and ncRNAs was revealed in the pathogenesis of WT. Functional modules were used to predict potential drugs which can be used in personalized therapy and drug delivery. This study explored the pathogenesis of WT from a new perspective, and provides new candidate targets and therapeutic drugs for improving the cure rate of WT.

miR-483-5p Targets MKNK1 to Suppress Wilms' Tumor Cell Proliferation and Apoptosis In Vitro and In Vivo

Background

Wilms’ tumor (WT) is the most common type of renal tumor in children and it has high mortality rates. MicroRNAs (miRNAs) are important regulators of cellular differentiation processes that have been discovered to contribute to the development of various kinds of tumors.

Material/Methods

The Wilms’ tumor tissues and adjacent tissues were obtained from 28 patients to quantity miR-483-5p expression level. The miR-483-5p mimics and scrambles were transfected into the human kidney WT cell line GHINK-1 to evaluate the effect of miR-483-5p on Wilms’ tumor cell proliferation and apoptosis in vitro. A total of 18 female BALB/c nu/nu mice were used to further confirm how miR-483-5p affects Wilms’ tumor in vivo.

Results

In the present study, miR-483-5p was identified to be downregulated in Wilms’ tumor tissues compared with the normal adjacent tissues. Additionally, low expression of mir-483-5p was significantly correlated with unfavorable histology subtypes, lymphatic metastasis, and late clinical stage (stage III and IV). Overexpression of miR-483-5p inhibited the proliferation and colony formation of GHINK-1 (Wilms’ tumor) cells compared with the control group due to enhanced cell apoptosis. Furthermore, miR-483-5p upregulated the protein expression level of caspase-3. Finally, MAP kinase-interacting serine/threonine-protein kinase 1 was identified as a direct target of miR-483-5p, which was confirmed by luciferase reporter assay and Western blotting.

Conclusions

MiR-483-5p suppressed WT cell proliferation via inducing apoptosis through targeting MKNK1. This may provide novel insights into the mechanisms underlying WT and a potential therapeutic candidate for the treatment of WT in the future.

The Rare Association of Cleft Lip and/or Palate and Wilms Tumor

There is currently no recognized connection between the occurrence of cleft lip and/or palate (CL/P) and Wilms tumor (WT). A retrospective review of cleft team records (2001-2015) revealed 3 cases of children, all male, with concomitant diagnoses of CL/P and WT treated at our institution. These patients presented as infants for care of their CL/P, all with additional congenital anomalies, developmental delays, and growth delays. Between the ages of 1 and 4 years, each was diagnosed with WT, which was treated with chemotherapy and partial nephrectomy, +/- radiation, leading to full remission in all cases.

Tamoxifen- and Mifepristone-Inducible Versions of CRISPR Effectors, Cas9 and Cpf1

Methods for making specific modifications to the genomes of living cells are powerful research tools. Two methods currently dominate, CRISPR and Cre recombinase. CRISPR has the advantage that it can act on unmodified target genes; Cre has the advantage of being available in drug-inducible versions, allowing temporal control, but it requires engineering ("floxing") of the target gene. Here, we have combined these advantages by constructing drug (tamoxifen/mifepristone)-inducible Cas9 and Cpf1 CRISPR effectors. We demonstrate their low background activity and robust activation with drugs, by using gRNAs to target them to TetR, in a cell carrying a Tet-repressed reporter gene. As well as being useful in their own right, the research tools generated here will pave the way to making further drug-inducible effector proteins.

Expression of transmembrane protein 41A is associated with metastasis via the modulation of E‑cadherin in radically resected gastric cancer

Gastric cancer (GC) is one of the most commonly occurring malignancies worldwide, and metastasis is one of the key processes affecting the prognosis of GC. TMEM41A, which belongs to a group of transmembrane proteins that participate in signaling pathways and tumor development, is a 264‑amino acid protein encoded by a gene mapped to human chromosome The exact role of TMEM41A in GC has not been determined to date. In the present study, the expression of TMEM41A in 147 cases of GC was analyzed with immunohistohemistry and the prognoses of these patients were analyzed. It was revealed that TMEM41A was highly expressed in GC tissues, and may be associated with the progression of GC and poor prognosis. The expression of TMEM41A was observed to be correlated with lymph node metastasis, distant metastasis and advanced tumor, node and metastasis stages. Knockdown of TMEM41A in vitro and in vivo decreased the GC cell migration ability by regulating epithelial‑to‑mesenchymal transition and cell autophagy, via the upregulation of E‑cadherin and downregulating N‑cadherin expression in GC cells by reverse transcription‑quantitative polymerase chain reaction (PCR), semi‑PCR and western blotting. Furthermore, TMEM41A upregulation was associated with the upregulation of p62 and altered the conversion of light chain (LC)3‑1 into LC3‑2 by western blotting. Knockdown of TMEM41A was also observed to affect tumor metastasis in nude mice. Therefore, TMEM41A may be considered as a novel therapeutic target for the treatment of GC‑associated metastasis.

Ossifying Renal Tumor of Infancy: Report of a Case With Positive WT1 Immunohistochemistry and High Mitotic Index and Review of the Literature

Ossifying renal tumor of infancy (ORTI) is a rare, benign pediatric tumor of the kidney. Since first reported by Chatten in 1980, 23 cases have been published. Previous authors have argued that ORTI might originate from nephrogenic rests, thereby sharing a pathogenic relationship with Wilms' tumor (WT). ORTI is characterized histologically by a population of polygonal osteoblast-like cells around an osteoid core and densely cellular component of blastemal-like or spindle cells. While the immunohistochemical profile of the cellular components has been reported, to the best of our knowledge, the status of WT1 expression has only been reported once, where it showed negative marking. Mitoses have been described only sporadically in this neoplasm. We report on a case of ORTI with positive WT1 immunohistochemical marking and numerous mitoses. This case highlights a possible pitfall for misdiagnosing ORTI as a WT and provides additional insight into its pathogenesis.

Multidrug resistance transporter profile reveals MDR3 as a marker for stratification of blastemal Wilms tumour patients

Wilms tumour (WT) is the most common renal tumour in children. Most WT patients respond to chemotherapy, but subsets of tumours develop resistance to chemotherapeutic agents, which is a major obstacle in their successful treatment. Multidrug resistance transporters play a crucial role in the development of resistance in cancer due to the efflux of anticancer agents out of cells. The aim of this study was to explore several human multidrug resistance transporters in 46 WT and 40 non-neoplastic control tissues (normal kidney) from patients selected after chemotherapy treatment SIOP 93–01, SIOP 2001. Our data showed that the majority of the studied multidrug resistance transporters were downregulated or unchanged between tumours and control tissues. However, BCRP1, MDR3 and MRP1 were upregulated in tumours versus control tissues. MDR3 and MRP1 overexpression correlated with high-risk tumours (SIOP classification) (p = 0.0022 and p < 0.0001, respectively) and the time of disease-free survival was significantly shorter in patients with high transcript levels of MDR3 (p = 0.0359). MDR3 and MRP1 play a role in drug resistance in WT treatment, probably by alteration of an unspecific drug excretion system. Besides, within the blastemal subtype, we observed patients with low MDR3 expression were significantly associated with a better outcome than patients with high MDR3 expression. We could define two types of blastemal WT associated with different disease outcomes, enabling the stratification of blastemal WT patients based on the expression levels of the multidrug resistance transporter MDR3.

A unified pathogenesis for kidney diseases, including genetic diseases and cancers, by the protein-homeostasis-system hypothesis

Every cell of an organism is separated and protected by a cell membrane. It is proposed that harmony between intercellular communication and the health of an organism is controlled by a system, designated the protein-homeostasis-system (PHS). Kidneys consist of a variety of types of renal cells, each with its own characteristic cell-receptor interactions and producing characteristic proteins. A functional union of these renal cells can be determined by various renal function tests, and harmonious intercellular communication is essential for the healthy state of the host. Injury to a kind of renal cells can impair renal function and induce an imbalance in total body health. Every acute or chronic renal disease has unknown etiologic substances that are responsible for renal cell injury at the molecular level. The immune/repair system of the host should control the etiologic substances acting against renal cells; if this system fails, the disease progresses to end stage renal disease. Each renal disease has its characteristic pathologic lesions where immune cells and immune proteins, such as immunoglobulins and complements, are infiltrated. These immune cells and immune proteins may control the etiologic substances involved in renal pathologic lesions. Also, genetic renal diseases and cancers may originate from a protein deficiency or malfunctioning protein under the PHS. A unified pathogenesis for renal diseases, including acute glomerulonephritis, idiopathic nephrotic syndrome, immunoglobulin A nephropathy, genetic renal diseases such as Alport syndrome, and malignancies such as Wilms tumor and renal cell carcinoma, is proposed using the PHS hypothesis.

Clinical, Pathologic, and Genetic Features of Wilms Tumors With WTX Gene Mutation

Clinical and pathologic features of patients with WTX-mutated Wilms tumor (WT) have not been studied in detail. We characterize the clinical and pathologic findings in WT with WTX abnormalities and provide comparison with WT without WTX mutation. Clinical, gross, and microscopic features in 35 patients with WT were examined. Karyotype was examined in a subset of cases. All cases had been previously analyzed for WTX, WT1, and CTNNB1 aberrations via array comparative genomic hybridization; OncoMap 4 high throughput genotyping was performed on 18 cases. Eleven tumors had WTX abnormality. No significant differences were identified between patients with mutated versus nonmutated WTX with respect to gender (45% versus 33% male), age (mean 3.9 versus 4.1 years), tumor size (mean 12.7 cm versus 12.8 cm), anaplasia (9% versus 12%), rhabdomyoblastic differentiation (18% versus 8%), cartilage differentiation (9% versus 4%), mucinous epithelial differentiation (9% versus 4%), nephrogenic rests (28% versus 21%), or relapse rate (11% versus 25%). Mutations in KRAS, MYC, and PIK3R1 were restricted to WTX-mutated WT, mutations in AKT, CKDN2A, EFGR, HRAS, MET, and RET were restricted to WT without WTX mutation, and mutations in BRAF, CTTNB1, NRAS, PDGFRA, and STK11 were seen in both groups. Our study revealed no clinical or pathologic distinctions between WT with and without WTX abnormality. This similarity lends support to the concept of a common tumorigenic pathway between WT with aberrant WTX and those without.

Axl promotes the proliferation, invasion and migration of Wilms' tumor and can be used as a prognostic factor

PURPOSE

Overexpression of Axl has been reported in many tumors, where it promotes tumorigenesis and progression, as well as correlates with the prognosis of different malignancies. However, Axl expression and its function have rarely been reported in Wilms' tumor (WT). This study aimed to reveal the clinical significance of Axl expression in patients with WT and determine its mechanisms.

MATERIALS AND METHODS

We analyzed the expression of Axl and its correlations with various clinicopathological features in 72 WT tissues and 72 adjacent non-cancerous tissues by immunohistochemistry. Cox proportional hazards regression models were used to investigate the correlations between Axl expression and the prognosis of WT patients. Fresh frozen samples from 20 WT patients were examined using Western blotting (WB) and real-time quantitative polymerase chain reaction (RT-qPCR). In WT cell line, after Axl knockdown by sh-Axl and growth arrest-specific 6 (Gas6) stimulation, the cell proliferation, migration and invasion abilities were detected by methyl-thiazolyl-tetrazolium (MTT), clone-forming, wound-healing and transwell assays. Meanwhile, the tumor-forming ability was tested on nude mice xenograft models. Finally, the expression of several proteins in signal pathways was quantified by WB assays.

RESULTS

Compared with the adjacent non-cancerous tissues, the expression of Axl was significantly higher in WT tissues (P<0.05). High expression of Axl was associated with tumor recurrence or lung metastasis of WT patients and was a prognostic factor for WT patients (P<0.05). In vitro assays, the proliferation, migration and invasion of WT cells decreased with Axl knockdown and significantly increased with Axl activation by Gas6 (P<0.05). In vivo assays, the ability of tumorigenicity in WT cells reduced dramatically after Axl knockout (P<0.05). Moreover, PI3K-Akt pathway proteins decreased with Axl knockdown.

CONCLUSION

Our results suggest that Axl is highly expressed in WT and is a prognostic factor, which could promote the progression of WT in vitro and in vivo. It may also be a potential biomarker for WT.

MALDI imaging mass spectrometry - From bench to bedside

Today, pathologists face many challenges in defining the precise morphomolecular diagnosis and in guiding clinicians to the optimal patients' treatment. To achieve this goal, increasingly, classical histomorphological methods have to be supplemented by high throughput molecular assays. Since MALDI imaging mass spectrometry (IMS) enables the assessment of spatial molecular arrangements in tissue sections, it goes far beyond microscopy in providing hundreds of different molecular images from a single scan without the need of target-specific reagents. Thus, this technology has the potential to uncover new markers for diagnostic purposes or markers that correlate with disease severity as well as prognosis and therapeutic response. Additionally, in the future MALDI IMS based classifiers measured with this technology in real time in the diagnostic setting might be applicable in the routine diagnostic setting. In this review, recently published studies that show the usefulness, advantages, and applicability of MALDI IMS in different fields of pathology (diagnosis, prognosis and treatment response) are highlighted. This article is part of a Special Issue entitled: MALDI Imaging, edited by Dr. Corinna Henkel and Prof. Peter Hoffmann.

Identification of proteins associated with pediatric bilateral Wilms tumor

Wilms tumor (WT) is the most common cancer that primarily develops in abdominal solid organ of children. It has no incipient symptom, and the most frequent symptoms are a painless, palpable abdominal mass. Proteomics technology was used to select the differentially expressed proteins of bilateral Wilms tumor (BWT). Ten serum samples of children with BWT were chosen, 20 serum samples of children with unilateral WT (UWT) and 20 serum samples of healthy children were selected, and proteomics technology was used to detect and collect data. Using bioinformatics, the data were analyzed and 10 difference peaks were obtained (P<0.01). Non-linear support vector machine was used to classify and to select the composite pattern with the highest Youdens index, and one differentially expressed protein with m/z of 5,648 kDa was obtained. A significantly high expression in children with BWT was obtained, and the expression intensity was also significantly (3,889.36±1,796.83) higher for children with BWT compared to those with UWT (2,886.81±1,404.65) and healthy children (432.21±730.42). Matrix-assisted laser desorption ionization/time-of-flight ionization/time-of-flight mass spectrometry was used for identification of the peak, and the peak was further identified as apolipoprotein C-III (APO C-III) by western blot analysis. In conclusion, to the best of our knowledge, a differentially expressed protein of APO C-III of BWT was obtained through proteomics technology for the first time, and it is expected to be a new marker for the early diagnosis and prognosis of BWT.

Andrographolide promotes vincristine-induced SK-NEP-1 tumor cell death via PI3K-AKT-p53 signaling pathway

Background

Nephroblastoma (Wilms’ tumor [WT]) is the most common malignant renal cancer in children. Although the outcome of WT has significantly improved as a result of the combination of surgery, chemotherapy, and radiotherapy; in some cases WT results in severe complications. Thus, novel strategies that would decrease treatment burden are required. The aim of the current study was to investigate the synergistic antitumor effect of andrographolide (AND) in combination with vincristine (VCR) on WT cells.

Methods

Cell Counting Kit-8 assay was used to investigate the synergistic antiproliferation effect of AND and/or VCR on SK-NEP-1 cells in vitro. Meanwhile, SK-NEP-1 xenografts were used to detect the antitumor effect in vivo. Apoptosis and autophagy were then detected by Annexin V, monodansylcadaverine staining. Finally, the underlying signaling transduction was determined with Western blotting.

Results

The combination of AND with VCR significantly suppressed SK-NEP-1 cell proliferation in vitro and inhibited xenograft tumor growth in vivo, compared with AND or VCR treatment alone. In addition, the synergistic antitumor effect of AND on the cells was due to an increased apoptosis, not autophagy. Moreover, PI3K-AKT-p53 signaling pathway was involved in the process of combination treatment, which was confirmed when a selective AKT activator was applied.

Conclusion

The combination of AND with VCR has a strong synergistic antitumor effect on WT via PI3K-AKT-p53 signaling pathway, thereby representing a potential treatment for WT in the near future.

Ossifying renal tumor of infancy (ORIT): The clinicopathological and cytogenetic feature of two cases and literature review

Ossifying renal tumor of infancy (ORTI) is a rare benign pediatric renal tumor, which has typical clinical and pathological features. In this article, the histological features, immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) assay of two cases of ORTI were performed and the literatures were reviewed. Both of the patients presented to hospital with painless gross hematuria without other symptoms. One is 6 months old male, another is 5-month-old. After several diagnostic procedures, they underwent surgery and the histological diagnosis of ORTI was finally made. Grossly, the tumor had a nodular or irregular appearance, often partially calcified and located in the renal pelvis and calyces. The cut surface of this mass was grey-white, solid and firm. Histologically, the tumor was composed of three major histologic components: osteoblast-like cells, spindle cells, and an osteoid core. Immunohistochemistry staining revealed that osteoblast-like cells were positive for EMA, Vimentin and STAB2. Spindle cells were strongly immunoreactive for Vimentin, WT-1 and focally positive for SMA, but were negative for CK, PAX8 and PAX2. The FISH studies with CEP4 probe on interphase nuclei from the two ORTIs, revealed trisomy 4 were 8.97% (case 1) and 12.23% (case 2). Our study showed that clonal trisomy 4 may be considered as a cytogenetic feature of ORTI, which makes it distinct from other pediatric renal tumor.

Preliminary observations regarding the expression of collagen triple helix repeat-containing 1 is an independent prognostic factor for Wilms' tumor

PURPOSE

Overexpression of collagen triple helix-repeat containing 1 (CTHRC1) has been reported in many malignancies, where it plays an important role in tumorigenesis and progression. This study aimed to examine the clinical significance of CTHRC1 expression in patients with Wilms' tumor (WT).

METHODS

The expression of CTHRC1, and its correlations with various clinicopathological parameters, was analyzed using immunohistochemistry in 42 WT tissues and 42 adjacent non-cancerous tissues. Samples from 8 patients with WT were examined using Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR). Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the correlations between CTHRC1 expression and the prognosis of patients with WT.

RESULTS

Immunohistochemistry, Western blotting, and qRT-PCR revealed that the expression of CTHRC1 was significantly higher in WT tumors, compared to the expression in the adjacent non-cancerous tissues. Furthermore, high tumor expression of CTHRC1 was associated with tumor size, clinical stage, histopathological type, and vascular invasion/metastasis. Moreover, the proportions of expressing cells in the WT specimens was higher than the proportions in the matched adjacent non-cancerous tissues. Kaplan-Meier analysis revealed that patients with high CTHRC1 expression exhibited a shorter survival, compared to patients with low CTHRC1 expression. Univariate and multivariate analyses also revealed that CTHRC1 expression was an independent prognostic factor for overall survival.

CONCLUSIONS

Our preliminary results suggest that CTHRC1 is an independent prognostic factor, which may play an important role in tumorigenesis and progression, and may be a potential biomarker for WT.

Next-generation sequencing reveals germline mutations in an infant with synchronous occurrence of nephro- and neuroblastoma

Although neuro- and nephroblastoma are common solid tumors in children, the simultaneous occurrence is very rare and is often associated with syndromes. Here, we present a unique case of synchronous occurrence of neuro- and nephroblastoma in an infant with no signs of congenital anomalies or a syndrome. We performed genetic testing for possible candidate genes as underlying mutation using the next-generation sequencing (NGS) approach to target 94 genes and 284 single-nucleotide polymorphisms (SNPs) involved in cancer. We uncovered a novel heterozygous germline missense mutation p.F58L (c.172T→C) in the anaplastic lymphoma kinase (ALK) gene and one novel heterozygous rearrangement Q418Hfs(*)11 (c.1254_1264delins TTACTTAGTACAAGAACTG) in the Fanconi anemia gene FANCD2 leading to a truncated protein. Besides, several SNPs associated with the occurrence of neuroblastoma and/or nephroblastoma or multiple primary tumors were identified. The next-generation sequencing approach might in the future be useful not only in understanding tumor etiology but also in recognizing new genetic markers and targets for future personalized therapy.

A role of WT1 in cell division and genomic stability

Wilms' tumor-1 protein (WT1) is a transcription factor that can either activate or repress genes to regulate cell growth, apoptosis and differentiation. WT1 can act as either a tumor suppressor or an oncogene. The cellular functions of WT1 are predominantly regulated by its various interacting partners. Recently we have found that WT1 can regulate the fidelity of chromosome segregation through its interaction with the spindle assembly checkpoint protein, Mitotic arrest deficient-2 (MAD2). WT1 delays anaphase entry by inhibiting the ubiquitination activity of the Anaphase promoting complex/cyclosome (APC/C). Our findings have revealed an important role of WT1 in the regulation of mitotic checkpoint and genomic stability.