Frequency and clinical impact of WT1 mutations in the context of CEBPA-mutated acute myeloid leukemia

INTRODUCTION

Several studies have confirmed that mutations in the Wilms tumor 1 (WT1) gene occur in adult acute myeloid leukemia (AML). However, few data are available regarding the incidence of WT1 mutations in CEBPA^mut AML and their impact.

METHODS

We retrospectively analyzed the frequency and clinical impact of WT1 mutations in 220 newly diagnosed AML patients with CEBPA mutations(CEBPA^mut). Chromosome karyotype analysis was performed by R or G banding method and further confirmed either by fluorescence in situ hybridization (FISH) and/or by multiple reverse transcription polymerase chain reaction (multiple RT-PCR). Mutations were detected with a panel of 112mutational genes using next-generation sequencing (NGS).

RESULTS

Overall, 30 WT1 mutations were detected in 29 of the 220 CEBPA^mut AML patients (13.18%) screened. These mutations clustered overwhelmingly in exon 7 (n=16). WT1 mutations were found to be significantly more frequent in AML patients with double-mutated CEBPA (CEBPA^dm) than in AML patients with single-mutated CEBPA (17.36%vs. 8.08%, P = 0.043). Among WT1-mutated patients, the most common co-mutation was FLT3-ITD (n = 7, 24.14%), followed by NRAS (n = 5, 17.24%), CSF3R (n = 4, 13.79%), GATA2 (n = 4, 13.79%), and KIT (n = 4, 13.79%). The most frequent functional pathway was signaling pathways inas many as 62.07% of cases. Notably,the concomitant mutations in epigenetic regulatorswere inversely correlated with WT1 mutations(P = 0.003). CEBPA^dm AML patients with WT1 mutations had inferior relapse-free survival, event-free survival and overall survival compared with patients CEBPA^dm AML without WT1 mutations (P = 0.002, 0.004, and 0.010, respectively).

CONCLUSION

Our data showed that WT1 mutations are frequently identified in CEBPA^mut AML, especially in CEBPA^dm AML. CEBPA^mut AML patients with WT1 mutations show distinct spectrum of comutations. In the context of CEBPA^dm AML, WT1 mutations predict a poor prognosis.

Appropriate Amounts and Activity of the Wilms' Tumor Suppressor Gene, wt1, Are Required for Normal Pronephros Development of Xenopus Embryos

The Wilms' tumor suppressor gene, wt1, encodes a zinc finger-containing transcription factor that binds to a GC-rich motif and regulates the transcription of target genes. wt1 was first identified as a tumor suppressor gene in Wilms' tumor, a pediatric kidney tumor, and has been implicated in normal kidney development. The WT1 protein has transcriptional activation and repression domains and acts as a transcriptional activator or repressor, depending on the target gene and context. In Xenopus, an ortholog of wt1 has been isolated and shown to be expressed in the developing embryonic pronephros. To investigate the role of wt1 in pronephros development in Xenopus embryos, we mutated wt1 by CRISPR/Cas9 and found that the expression of pronephros marker genes was reduced. In reporter assays in which known WT1 binding sequences were placed upstream of the luciferase gene, WT1 activated transcription of the luciferase gene. The injection of wild-type or artificially altered transcriptional activity of wt1 mRNA disrupted the expression of pronephros marker genes in the embryos. These results suggest that the appropriate amounts and activity of WT1 protein are required for normal pronephros development in Xenopus embryos.

Study of mRNA of WT1, BAALC, EVI1, PRAME and HMGA2 genes in whole blood samples

Simultaneous quantitative measurement of mRNA of the WT1, BAALC, EVI1, PRAME and HMGA2 genes in whole blood samples reflects the specific pathological proliferative activity in acute leukemia and their ratio is promising as a diagnostic marker. The transcriptome profile of acute leukemia cells is usually assessed using NGS or microarray techniques after a preliminary procedure for isolation of mononuclear cells. However, the results of using the multiplex PCR reaction for the simultaneous determination of all above mRNAs in whole blood samples have not been published so far. Determination of mRNA of WT1, BAALC, EVI1, PRAME and HMGA2 genes in venous blood level samples by multiplex RT-PCR. The study included 127 blood samples from patients who diagnosis of acute leukemia was subsequently confirmed. In the comparison group, 87 samples of patients without oncohematological diagnosis were selected, including 31 samples (K1) with a normal blood formula and 56 samples (K2) with a violation of the cellular composition - anemia, leukocytosis and thrombocytopenia. RNA isolation and reverse transcription were performed using the Ribozol-D and Reverta-L kits (TsNIIE, Russia). Determination of the mRNA expression level of the WT1, BAALC, EVI1, PRAME and HMGA2 genes by multiplex real-time PCR using a homemade multiplex PCR kit. The mRNA level was characterized by high interindividual variation and did not correlate with the rate of circulating leukocytes or blood blasts. Expression of WT1 mRNA was observed in whole blood only in one patient from the control group and in 112 (88%) patients with leukemia and was combined with a decrease in the level of HMGA2 mRNA expression and BAALC mRNA values. In contrast to the control groups, patients with leukemia had higher levels of BAALC mRNA in AML and ALL, increased PRAME mRNA in AML and APL, but lower levels of HMGA2 in APL.

Combined PD-L1 and TIM3 blockade improves expansion of fit human CD8+ antigen-specific T cells for adoptive immunotherapy

Antigen-specific T cell expansion ex vivo followed by adoptive transfer enables targeting of a multitude of microbial and cancer antigens. However, clinical-scale T cell expansion from rare precursors requires repeated stimulation, which may lead to T cell dysfunction and limited therapeutic potential. We used a clinically compliant protocol to expand Epstein-Barr virus (EBV) and Wilms tumor 1 (WT1) antigen-specific CD8⁺ T cells, and leveraged T cell exhaustion-associated inhibitory receptor blockade to improve T cell expansion. Several inhibitory receptors were expressed early by ex vivo-expanded antigen-specific CD8⁺ T cells, including PD-1 and TIM3, with co-expression matching evidence of T cell dysfunction as the cultures progressed. Introduction of anti-PD-L1 and anti-TIM3 blockade in combination (but not individually) to the culture led to markedly improved antigen-specific T cell expansion without inducing T cell dysfunction. Single-cell RNA sequencing (RNA-seq) and T cell receptor (TCR) repertoire profiling revealed that double blockade does not impart specific transcriptional programs in T cells or alterations in TCR repertoires. However, combined blockade may affect gene expression in a minority of clonotypes in a donor-specific fashion. We conclude that antigen-specific CD8⁺ T cell manufacturing can be improved by using TIM3 and PD-L1/PD-1 axis blockade in combination. This approach is readily applicable to several adoptive immunotherapy strategies.

The pathophysiology of bilateral and multifocal Wilms tumors: What we can learn from the study of predisposition syndromes

Approximately 5% of patients with Wilms tumor present with synchronous bilateral disease. The development of synchronous bilateral Wilms tumor (BWT) is highly suggestive of a genetic or epigenetic predisposition. Patients with known germline predisposition to Wilms tumor (WT1 variants, Beckwith Wiedemann spectrum, TRIM28 variants) have a higher incidence of BWT. This Children's Oncology Group (COG)-International Society for Pediatric Oncology (SIOP-) HARMONICA initiative review for pediatric renal tumors details germline genetic and epigenetic predisposition to BWT development, with an emphasis on alterations in 11p15.5 (ICR1 gain of methylation, paternal uniparental disomy, and postzygotic somatic mosaicism), WT1, TRIM28, and REST. Molecular mechanisms that result in BWT are often also present in multifocal Wilms tumor (multiple separate tumors in one or both kidneys). We identify priority areas for international collaborative research to better understand how predisposing genetic or epigenetic factors associate with response to neoadjuvant chemotherapy, oncologic outcomes, and long-term renal function outcomes.

The Role of Wilms' Tumor Gene (WT1) Expression as a Marker of Minimal Residual Disease in Acute Myeloid Leukemia

The Minimal Residual Disease(MRD) monitoring in acute myeloid leukemia (AML) is crucial to guide treatment after morphologic complete remission, to define the need for consolidation with allogeneic stem cell transplantation (Allo-SCT), and to detect impending relapse allowing early intervention. However, more than 50% of patients with AML lack a specific or measurable molecular marker to monitor MRD. We reviewed the key studies on WT1 overexpression as a marker of MRD in AML patients undergoing an intensive chemotherapy program, including Allo-SCT. In addition, we provided some practical considerations on how to properly use WT1 expression as an MRD marker, considering its strengths and weaknesses. In order to achieve the best sensitivity and specificity, it is recommended to refer to the standardized method of European LeukemiaNet and its defined threshold (250 WT1 copies/10⁴ Abelson (ABL) on Bone Marrow-BM and 50 WT1 copies/10⁴ ABL on Peripheral Blood-PB), which has been validated in a large and multicenter cohort of patients and normal controls.

Prognostic impact of PRDM16 expression in acute myeloid leukemia with normal cytogenetics

PURPOSE

Cytogenetically normal acute myeloid leukemia (CN-AML) is a heterogeneous disease with variable clinical outcomes. The identification of potential biomarkers to better classify the patients with unfavorable prognoses who may require more aggressive therapies is an emergent demand. PRDM16 is a transcriptional cofactor and histone methyltransferase, playing a critical role in maintaining hematopoietic stem cells, and MLL fusion-induced leukemogenesis. However, the prognostic value of PRDM16 in CN-AML is still unclear.

MATERIALS AND METHODS

We retrospectively analyzed the PRDM16 expression and its association with gene mutations in CN-AML. Then the prognostic value of PRDM16 and its comparison with WT1 were analyzed.

RESULTS

The results showed that about 73.6% of CN-AML patients harbored higher expression of PRDM16 than the healthy controls. Furthermore, CN-AML patients with high PRDM16 expression had a lower survival rate than the low PRDM16 expression group (50.5% vs. 83.3%, p = 0.0339). Interestingly, hemopoietic stem cell transplantation significantly improved the prognosis of CN-AML with high PRDM16 expression but not those with low PRDM16 expression. In terms of molecular genetics, high PRDM16 expression was significantly associated with a lower rate of CEBPA mutation (p = 0.01) and a higher rate of FLT3-ITD and DNMT3A mutation (p = 0.032 and p = 0.004, respectively). In addition, PRDM16 expression was significantly correlated with WT1 expression in CN-AML (r = 0.7, p < 0.001). These data suggested PRDM16 expression could be used to predict the outcome of patients with CN-AML.

CONCLUSION

PRDM16 is significantly associated with FLT3-ITD and DNMT3A mutation and WT1 expression and serves as a potential prognostic biomarker in CN-AML.

First-in-human study of WT1 recombinant protein vaccination in elderly patients with AML in remission: a single-center experience

Wilms’ tumor 1 (WT1) protein is highly immunogenic and overexpressed in acute myeloid leukemia (AML), consequently ranked as a promising target for novel immunotherapeutic strategies. Here we report our experience of a phase I/II clinical trial (NCT01051063) of a vaccination strategy based on WT1 recombinant protein (WT1-A10) together with vaccine adjuvant AS01_B in five elderly AML patients (median age 69 years, range 63–75) receiving a total of 62 vaccinations (median 18, range 3–20) after standard chemotherapy. Clinical benefit was observed in three patients: one patient achieved measurable residual disease clearance during WT1 vaccination therapy, another patient maintained long-term molecular remission over 59 months after the first vaccination cycle. Interestingly, in one case, we observed a complete clonal switch at AML relapse with loss of WT1 expression, proposing suppression of the original AML clone by WT1-based vaccination therapy. Detected humoral and cellular CD4⁺ T cell immune responses point to efficient immune stimulation post-vaccination, complementing hints for induced conventional T cell infiltration into the bone marrow and a shift from senescent/exhausted to a more activated T cell profile. Overall, the vaccinations with WT1 recombinant protein had an acceptable safety profile and were thus well tolerated.

To conclude, our data provide evidence of potential clinical efficacy of WT1 protein-based vaccination therapy in AML patients, warranting further investigations.

Platelet to white blood cell ratio was an independent prognostic predictor in acute myeloid leukemia

BACKGROUND

Recently, platelet to white blood cell ratio (PWR) was reported as an independent prognostic predictor in acute promyelocytic leukemia. Acute myeloid leukemia (AML) often presents with abnormal platelet counts and white blood cell counts (WBC) at disease diagnosis. However, the clinical impact of PWR on cytogenetically normal AML (CN-AML) is still unclear. Therefore, we evaluate its prognostic impact on CN-AML patients.

METHODS

We recorded the clinical information at the time of disease diagnosis, and calculated the ratio of platelet counts to WBC in 338 patients with CN-AML. To assess the prognostic value of PWR, we divided patients into low, intermediate and high group based on the values of PWR. The independent prognostic value of PWR was investigated in the context of the well-established predictors including white blood cell counts, age, and genes of NPM1, FLT3-ITD, CEBPA, and DNMT3A mutations. Receiver operating characteristic (ROC) curve was used to assess the performance of its prognostic prediction.

RESULTS

Higher PWR have the higher levels of platelet counts, but lower levels of white blood cell counts, percentage of bone marrow blasts, FLT3-ITD and NPM1 mutations. The performance of survival prediction was comparable between PWR alone and combined molecular biomarkers. Moreover, PWR had the additional prognostic information to the molecular biomarkers. Finally, PWR was associated with favorable overall survival and event free survival in CN-AML patients independent of genetic subtypes and clinical parameters.

CONCLUSION

We found PWR was an independent prognostic predictor in CN-AML.

Wt1 haploinsufficiency induces browning of epididymal fat and alleviates metabolic dysfunction in mice on high-fat diet

AIMS/HYPOTHESIS

Despite a similar fat storing function, visceral (intra-abdominal) white adipose tissue (WAT) is detrimental, whereas subcutaneous WAT is considered to protect against metabolic disease. Recent findings indicate that thermogenic genes, expressed in brown adipose tissue (BAT), can be induced primarily in subcutaneous WAT. Here, we investigate the hypothesis that the Wilms tumour gene product (WT1), which is expressed in intra-abdominal WAT but not in subcutaneous WAT and BAT, suppresses a thermogenic program in white fat cells.

METHODS

Heterozygous Wt1 knockout mice and their wild-type littermates were examined in terms of thermogenic and adipocyte-selective gene expression. Glucose tolerance and hepatic lipid accumulation in these mice were assessed under normal chow and high-fat diet conditions. Pre-adipocytes isolated from the stromal vascular fraction of BAT were transduced with Wt1-expressing retrovirus, induced to differentiate and analysed for the expression of thermogenic and adipocyte-selective genes.

RESULTS

Expression of the thermogenic genes Cpt1b and Tmem26 was enhanced and transcript levels of Ucp1 were on average more than tenfold higher in epididymal WAT of heterozygous Wt1 knockout mice compared with wild-type mice. Wt1 heterozygosity reduced epididymal WAT mass, improved whole-body glucose tolerance and alleviated severe hepatic steatosis upon diet-induced obesity in mice. Retroviral expression of WT1 in brown pre-adipocytes, which lack endogenous WT1, reduced mRNA levels of Ucp1, Ppargc1a, Cidea, Prdm16 and Cpt1b upon in vitro differentiation by 60-90%. WT1 knockdown in epididymal pre-adipocytes significantly lowered Aldh1a1 and Zfp423 transcripts, two key suppressors of the thermogenic program. Conversely, Aldh1a1 and Zfp423 mRNA levels were increased approximately five- and threefold, respectively, by retroviral expression of WT1 in brown pre-adipocytes.

CONCLUSION/INTERPRETATION

WT1 functions as a white adipocyte determination factor in epididymal WAT by suppressing thermogenic genes. Reducing Wt1 expression in this and other intra-abdominal fat depots may represent a novel treatment strategy in metabolic disease.

Role of miRNA-671-5p in Mediating Wnt/β-Catenin-Triggered Podocyte Injury

Podocyte injury and proteinuria are the most common features of glomerular disease, which is the leading cause of end-stage renal failure. Hyperactivated Wnt/β-catenin signaling is closely associated with podocyte injury, but the underlying mechanisms are incompletely understood. Here we show that miRNA-671-5p (miR-671-5p) plays a crucial role in mediating β-catenin-triggered podocyte injury by targeting Wilms tumor 1 (WT1). Microarray-based expression profiling revealed that miR-671-5p was the most upregulated miRNA in podocytes after β-catenin activation. MiR-671-5p was colocalized with β-catenin in the glomeruli of proteinuric CKD in vivo. Bioinformatics analyses and luciferase reporter assays confirmed that miR-671-5p targeted WT1 mRNA. Overexpression of miR-671-5p mimics inhibited WT1 and impaired podocyte integrity, whereas miR-671-5p antagomir preserved the expression of WT1 and other podocyte-specific proteins under basal conditions or after β-catenin activation. In mouse remnant kidney model, overexpression of miR-671-5p aggravated podocyte injury, worsened kidney dysfunction and exacerbated renal fibrosis after 5/6 nephrectomy. In contrast, miR-671-5p antagomir alleviated podocyte injury and attenuated proteinuria and renal fibrotic lesions after glomerular injury in vivo. These studies underscore a pivotal role of miR-671-5p in mediating WT1 depletion and podocyte injury induced by β-catenin. Targeting miR-671-5p may serve as a new approach to prevent podocyte injury and proteinuria in proteinuric CKD.

IL-6 coaxes cellular dedifferentiation as a pro-regenerative intermediate that contributes to pericardial ADSC-induced cardiac repair

Background

Cellular dedifferentiation is a regenerative prerequisite that warrants cell cycle reentry and appropriate mitotic division during de novo formation of cardiomyocytes. In the light of our previous finding that expression of injury-responsive element, Wilms Tumor factor 1 (WT1), in pericardial adipose stromal cells (ADSC) conferred a compelling reparative activity with concomitant IL-6 upregulation, we then aim to unravel the mechanistic network that governs the process of regenerative dedifferentiation after ADSC-based therapy.

Methods and results

WT1-expressing ADSC (eGFP:WT1) were irreversibly labeled in transgenic mice (WT1-iCre/Gt(ROSA)26Sor-eGFP) primed with myocardial infarction. EGFP:WT1 cells were enzymatically isolated from the pericardial adipose tissue and cytometrically purified (ADSC^gfp+). Bulk RNA-seq revealed upregulation of cardiac-related genes and trophic factors in ADSC^gfp+ subset, of which IL-6 was most abundant as compared to non-WT1 ADSC (ADSC^gfp−). Injection of ADSC^gfp+ subset into the infarcted hearts yielded striking structural repair and functional improvement in comparison to ADSC^gfp− subset. Notably, ADSC^gfp+ injection triggered significant quantity of dedifferentiated cardiomyocytes recognized as round-sharp, marginalization of sarcomeric proteins, expression of molecular signature of non-myogenic genes (Vimentin, RunX1), and proliferative markers (Ki-67, Aurora B and pH3). In the cultured neonatal cardiomyocytes, spontaneous dedifferentiation was accelerated by adding tissue extracts from the ADSC-treated hearts, which was neutralized by IL-6 antibody. Genetical lack of IL-6 in ADSC dampened cardiac dedifferentiation and reparative activity.

Conclusions

Taken collectively, our results revealed a previous unappreciated effect of IL-6 on cardiac dedifferentiation and regeneration. The finding, therefore, fulfills the promise of stem cell therapy and may represent an innovative strategy in the treatment of ischemic heart disease.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02675-1.

Autophagy regulates differentiation of ovarian granulosa cells through degradation of WT1

Ovarian granulosa cells (GCs) proliferate and differentiate along with follicular growth, and this is indispensable for oocyte development and female fertility. Although the role of macroautophagy/autophagy in ovarian function has been reported, its contribution to the regulation of GC characteristics remains elusive. The siRNA-mediated knockdown of two key autophagy-related genes ATG5 and BECN1 and the autophagy inhibitor chloroquine were used to interfere with autophagy in GCs. Inhibition of autophagy both genetically and pharmacologically resulted in decreased expression of genes associated with GC differentiation, including CYP19A1/Aromatase and FSHR, as well as in reduced estradiol synthesis. Mechanistically, when autophagy was disrupted, the transcription factor WT1 accumulated in GCs due to its insufficient degradation by the autophagic pathway, and this inhibited GC differentiation. Finally, decreased expression of several autophagy-related genes, as well as reduced LC3-II:LC3-I and elevated SQSTM1/p62 protein levels, which are indications of decreased autophagy, were detected in GCs from biochemical premature ovarian insufficiency patients. In summary, our study reveals that autophagy regulates the differentiation of ovarian GCs by degrading WT1 and that insufficient autophagy might be involved in ovarian dysfunction.

WT1 complete gonadal dysgenesis with membranoproliferative glomerulonephritis: case series and literature review

BACKGROUND

Intronic WT1 mutations are usually causative of Frasier syndrome with focal segmental glomerulosclerosis as the characteristic nephropathy. Membranoproliferative glomerulonephritis is not commonly associated with disorders of sex development but has been recently identified as a WT1-associated nephropathy, but usually in cases of exonic mutations in either isolated Wilms tumor or Denys-Drash syndrome.

METHODS

The clinical and genetic data from 3 individuals are reported.

RESULTS

This report describes the kidney manifestations in 3 individuals from 2 unrelated families with Frasier syndrome intronic WT1 mutations, noting that 2 of the 3 individuals have histologically confirmed membranoproliferative glomerulonephritis.

CONCLUSIONS

These case reports support expansion of the clinical spectrum of the kidney phenotypes associated with Frasier syndrome providing evidence of an association between WT1 mutation and an immune complex-related membranoproliferative glomerulonephritis. A higher resolution version of the Graphical abstract is available as Supplementary information.

Pleural Mesothelial Cells Modulate the Inflammatory/Profibrotic Response During SARS-CoV-2 Infection

Although lung fibrosis has a major impact in COVID-19 disease, its pathogenesis is incompletely understood. In particular, no direct evidence of pleura implication in COVID-19-related fibrotic damage has been reported so far. In this study, the expression of epithelial cytokeratins and Wilms tumor 1 (WT1), specific markers of mesothelial cells (MCs), was analyzed in COVID-19 and unrelated pleura autoptic samples. SARS-CoV-2 replication was analyzed by RT-PCR and confocal microscopy in MeT5A, a pleura MC line. SARS-CoV-2 receptors were analyzed by RT-PCR and western blot. Inflammatory cytokines from the supernatants of SARS-CoV-2-infected MeT5A cells were analysed by Luminex and ELLA assays. Immunohistochemistry of COVID-19 pleura patients highlighted disruption of pleura monolayer and fibrosis of the sub-mesothelial stroma, with the presence of MCs with fibroblastoid morphology in the sub-mesothelial stroma, but no evidence of direct infection in vivo. Interestingly, we found evidence of ACE2 expression in MCs from pleura of COVID-19 patients. In vitro analysis shown that MeT5A cells expressed ACE2, TMPRSS2, ADAM17 and NRP1, plasma membrane receptors implicated in SARS-CoV-2 cell entry and infectivity. Moreover, MeT5A cells sustained SARS-CoV-2 replication and productive infection. Infected MeT5A cells produced interferons, inflammatory cytokines and metalloproteases. Overall, our data highlight the potential role of pleura MCs as promoters of the fibrotic reaction and regulators of the immune response upon SARS-CoV-2 infection.

WT1 suppresses follicle-stimulating hormone-induced progesterone secretion by regulating ERK1/2 pathway in chicken preovulatory granulosa cells

Multiple Wilms tumor gene 1 (WT1) splicing variants are expressed in mammals, and these variants regulate tumorigenesis and mediate the development of multiple tissues and organs, including gonads. However, WT1 splicing variants (+KTS or -KTS) are expressed in only two nonmammalian vertebrates, and unexpectedly, their functions in chicken ovaries remain elusive. Progesterone (P4) secreted by chicken granulosa cells (GCs) participates in various physiological processes and plays an important role in maintaining reproductive performance. The purpose of this study was to investigate the effect of WT1(+KTS) and WT1(-KTS) on chicken P4 secretion in preovulatory GCs. First, we detected WT1 mRNA expression in GCs from follicles of different developmental stages by Quantitative real-time PCR (RT-qPCR) and found that WT1 mRNA expression was considerably increased in preovulatory GCs compared with prehierarchical GCs. Primary cells collected from preovulatory follicles were treated with WT1(+KTS) or WT1(-KTS) overexpression vectors and subsequently cultured in the absence or presence of follicle-stimulating hormone (FSH). The mRNA levels of FSH-receptor (FSHR) and steroidogenesis genes were determined by RT-qPCR, and the P4 levels in the cell supernatants were measured by radioimmunoassay (RIA). Both WT1(+KTS) and WT1(-KTS) significantly decreased P4 secretion due to a reduction in FSHR, STAR and CYP11A1 mRNA levels. Western blotting revealed that ERK1/2 and BRAF phosphorylation levels were suppressed after overexpression of WT1(+KTS) or WT1(-KTS), whereas total protein and mRNA levels were not significantly changed. In addition, CREB protein and phosphorylation levels were inhibited after overexpression of WT1(+KTS) or WT1(-KTS). In conclusion, WT1(+KTS) and WT1(-KTS) inhibited CREB protein activity and significantly reduced FSHR, STAR and CYP11A1 mRNA levels, which subsequently suppressed FSH-induced P4 secretion in preovulatory GCs by modulating ERK1/2 signaling.

Optimal time-points for detecting expression levels of BAALC, EVI1, and WT1 genes in patients with acute myeloid leukemia: a meta-analysis

OBJECTIVES

This meta-analysis examined the prognostic role of brain and acute leukemia, cytoplasmic (BAALC), Ecotropic virus integration site-1 (EVI1) and Wilms' tumor 1 (WT1) genes at different time-points during conventional chemotherapy.

METHODS

A systematic search of publications indexed in the electronic databases from January 1988 to October 2020 was performed. Over 7525 cases of AML from 25 studies were involved.

RESULTS

At diagnosis, overexpression of either BAALC or EVI1 had a negative impact on complete remission achievement (Summary Odds ratios [SORs] for BAALC = 0.32; SORs for EVI1 = 0.49) and survival outcome. The summary hazard ratios of overall survival (OS) and disease-free survival (DFS) were 1.97 and 2.04 for BAALC and 1.33 and 1.86 for EVI1, respectively. The prognostic value of pretreatment WT1 levels was heterogeneous while subgroup analyses unveiled that overexpressed WT1 may correlate with a favorable outcome (summary hazard ratio [SHR] for OS = 0.42). Both WT1 and BAALC played a role in prognosis assessment at post-induction and the diagnostic performance of WT1 transcript reduction was superior to the absolute WT1 level. Post-consolidation WT1 overexpression consistently indicated an increased risk of relapse, while the combined HR for RFS was statistically insignificant (SHR = 4.22).

CONCLUSION

These findings confirm the application of BAALC and EVI1 at diagnosis, WT1 after induction chemotherapy in AML patients throughout conventional chemotherapy.

lncRNA DDGC participates in premature ovarian insufficiency through regulating RAD51 and WT1

The list of long non-coding RNAs (lncRNAs) that participate in the function of ovarian granulosa cells (GCs) is rapidly expanding, but the mechanisms through which lncRNAs regulate GC function are not yet fully understood. Here, we recognized a minimally expressed lncRNA RP4-545C24.1 (which we named DDGC) in GCs from patients with biochemical premature ovarian insufficiency (bPOI). We further explored the role of lncRNA DDGC in GC function and its contribution to the development of bPOI. Mechanistically, silencing DDGC downregulated RAD51 by competitively binding with miR-589-5p, and this resulted in significant inhibition of DNA damage repair capacity. In addition, decreased expression of DDGC promoted ubiquitin-mediated degradation of Wilms tumor 1 (WT1) protein through interactions with heat shock protein 90 (HSP90), which led to aberrant differentiation of GCs. Moreover, DDGC was able to ameliorate the etoposide-induced DNA damage and apoptosis in vivo. Taken together, these findings provide new insights into the contribution of lncRNAs in POI pathogenesis.

Baseline immunity predicts prognosis of pancreatic cancer patients treated with WT1 and/or MUC1 peptide-loaded dendritic cell vaccination and a standard chemotherapy

The prognosis of patients with advanced pancreatic cancer is poor despite the recent introduction of immune checkpoint inhibitors. Therefore, the development of new therapeutic approaches is urgently required. In the present phase I/II study, we have evaluated the safety, the efficacy and the prognostic factors of Wilms' tumor 1 (WT1) and/or mucin 1 (MUC1) peptide-loaded dendritic cell (DC) vaccination in combination with a chemotherapy employing gemcitabine plus nab-paclitaxel or a combination chemotherapy regimen consisting of oxaliplatin, irinotecan, fluorouracil and leucovorin (FOLFIRINOX) in patients with advanced or relapsed pancreatic ductal adenocarcinoma (PDAC). Forty-eight eligible patients were enrolled and received the vaccinations approximately every 2-4 weeks at least seven times. No severe adverse events related to the vaccinations were observed. Median progression free survival and overall survival were 8.1 months and 15.1 months, respectively. DC vaccinations augmented tumor specific immunity which might be related to clinical outcome. The multivariate analyses demonstrated that WT1 or MUC1-specific interferonɤ enzyme-linked immunospot number prior to DC vaccination was an independent prognostic factor related to overall survival. These results indicate that DC-based immunotherapy combined with a conventional chemotherapy is safe and has clinical benefits for patients in advanced stage of PDAC. The precise evaluation of the baseline antitumor specific immunity is critical to predict clinical outcome.

Whole exome sequencing identified a rare WT1 loss-of-function variant in a non-syndromic POI patient

Background

Premature ovarian insufficiency (POI) is a highly heterogeneous disease, and up to 25% of cases can be explained by genetic causes. The transcription factor WT1 has long been reported to play a crucial role in ovary function. Wt1‐mutated female mice exhibited POI‐like phenotypes.

Methods and Results

In this study, whole exome sequencing (WES) was applied to find the cause of POI in Han Chinese women. A nonsense variant in the WT1 gene: NM_024426.6:c.1387C>T(p.R463*) was identified in a non‐syndromic POI woman. The variant is a heterozygous de novo mutation that is very rare in the human population. The son of the patient inherited the mutation and developed Wilms’ tumor and urethral malformation at the age of 7. According to the American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG/AMP) guidelines, the novel variant is categorized as pathogenic. Western blot analysis further demonstrated that the WT1 variant could produce a truncated WT1 isoform in vitro.

Conclusions

A rare heterozygous nonsense WT1 mutant is associated with non‐syndromic POI and Wilms’ tumor. Our finding characterized another pathogenic WT1 variant, providing insight into genetic counseling.

MicroRNA-21 enhances estradiol production by inhibiting WT1 expression in granulosa cells

In antral follicles, the transition of proliferative granulosa cells to estradiol-producing is critical for proper oocyte maturation. MicroRNAs are noncoding RNAs that play important roles in ovarian follicular development; however, this has yet to be fully characterized. MicroRNA-21 is significantly higher in granulosa cells isolated from large antral follicles compared to those from small antral follicles. To investigate the function of miR-21, porcine granulosa cells were transfected with miR-21 mimic or miR-21 targeted siRNA. Cells with the miR-21 mimic had higher aromatase expression and estradiol production but decreased WT1 expression. Conversely, cells with the miR-21 siRNA secreted less estradiol and had higher WT1 expression. We hypothesized that miR-21 promotes estradiol production by inhibiting WT1 protein synthesis. We found a potential miR-21 binding site in the 3'UTR of the WT1 transcript and performed a dual-luciferase reporter assay using the WT and mutated 3'UTR. Compared to the negative control, the miR-21 mimic induced a significant decrease in luciferase activity in the WT 3'UTR. This decrease was reversed when the 3'UTR was mutated, suggesting miR-21 targets this site to inhibit WT1 expression. We next transfected porcine granulosa cells with WT1 targeted siRNA and observed a significant increase in aromatase expression and estradiol secretion. We propose that miR-21 represses WT1 expression in granulosa cells to potentially promote aromatase expression and estradiol production. This study offers the first report of a microRNA regulating WT1 expression in granulosa cells and reveals the role of miR-21 in WT1's regulation of estradiol production.

Higher Expression of WT1 With Lower CD58 Expression may be Biomarkers for Risk Stratification of Patients With Cytogenetically Normal Acute Myeloid Leukemia

Background: Cytogenetics at diagnosis is the most important prognostic factor for adult acute myeloid leukemia (AML), but nearly 50% of AML patients who exhibit cytogenetically normal AML (CN-AML) do not undergo effective risk stratification. Therefore, the development of potential biomarkers to further define risk stratification for CN-AML patients is worth exploring. Methods: Transcriptome data from 163 cases in the GSE12417-GPL96 dataset and 104 CN-AML patient cases in the GSE71014-GPL10558 dataset were downloaded from the Gene Expression Omnibus database for overall survival (OS) analysis and validation. Results: The combination of Wilms tumor 1 (WT1) and cluster of diffraction 58 (CD58) can predict the prognosis of CN-AML patients. High expression of WT1 and low expression of CD58 were associated with poor OS in CN-AML. Notably, when WT1 and CD58 were used to concurrently predict OS, CN-AML patients were divided into three groups: low risk, WT1^lowCD58^high; intermediate risk, WT1^highCD58^high or WT1^lowCD58^low; and high risk, WT1^highCD58^low. Compared with low-risk patients, intermediate- and high-risk patients had shorter survival time and worse OS. Furthermore, a nomogram model constructed with WT1 and CD58 may personalize and reveal the 1-, 2-, 3-, 4-, and 5-year OS rate of CN-AML patients. Both time-dependent receiver operating characteristics and calibration curves suggested that the nomogram model demonstrated good performance. Conclusion: Higher expression of WT1 with lower CD58 expression may be a potential biomarker for risk stratification of CN-AML patients. Moreover, a nomogram model constructed with WT1 and CD58 may personalize and reveal the 1-, 2-, 3-, 4-, and 5-year OS rates of CN-AML patients.