Genistein improves renal disease in a mouse model of nephropathic cystinosis: a comparison study with cysteamine.

Cysteamine is currently the only therapy for nephropathic cystinosis. It significantly improves life expectancy and delays progression to end-stage kidney disease; however, it cannot prevent it. Unfortunately, compliance to therapy is often weak, particularly during adolescence. Therefore, finding better treatments is a priority in the field of cystinosis. Previously, we found that genistein, an isoflavone particularly enriched in soy, can revert part of the cystinotic cellular phenotype that is not sensitive to cysteamine in vitro. To test the effects of genistein in vivo, we fed 2-month-old wild-type and Ctns-/- female mice with either a control diet, a genistein-containing diet or a cysteamine-containing diet for 14 months. Genistein (160 mg/kg/day) did not affect the growth of the mice or hepatic functionality. Compared with untreated mice at 16 months, Ctns-/- mice fed with genistein had lower cystine concentrations in their kidneys, reduced formation of cystine crystals, a smaller number of LAMP1-positive structures and an overall better-preserved parenchymal architecture. Cysteamine (400 mg/kg/day) was efficient in reverting the lysosomal phenotype and in preventing the development of renal lesions. These preclinical data indicate that genistein ameliorates kidney injury resulting from cystinosis with no side effects. Genistein therapy represents a potential treatment to improve the outcome for patients with cystinosis.

Multisystem involvement, defective lysosomes and impaired autophagy in a novel rat model of nephropathic cystinosis.

Recessive mutations in the CTNS gene encoding the lysosomal transporter cystinosin cause cystinosis, a lysosomal storage disease leading to kidney failure and multisystem manifestations. A Ctns knockout mouse model recapitulates features of cystinosis, but the delayed onset of kidney manifestations, phenotype variability and strain effects limit its use for mechanistic and drug development studies. To provide a better model for cystinosis, we generated a Ctns knockout rat model using CRISPR/Cas9 technology. The Ctns-/- rats display progressive cystine accumulation and crystal formation in multiple tissues including kidney, liver and thyroid. They show an early onset and progressive loss of urinary solutes, indicating generalized proximal tubule dysfunction, with development of typical swan-neck lesions, tubulointerstitial fibrosis and kidney failure, and decreased survival. The Ctns-/- rats also present crystals in the cornea, and bone and liver defects, as observed in patients. Mechanistically, the loss of cystinosin induces a phenotype switch associating abnormal proliferation and dedifferentiation, loss of apical receptors and transporters, and defective lysosomal activity and autophagy in the cells. Primary cultures of proximal tubule cells derived from the Ctns-/- rat kidneys confirmed the key changes caused by cystine overload, including reduced endocytic uptake, increased proliferation and defective lysosomal dynamics and autophagy. The novel Ctns-/- rat model and derived proximal tubule cell system provide invaluable tools to investigate the pathogenesis of cystinosis and to accelerate drug discovery.

Pigmented median raphe cyst of the scrotum. A rare pediatric case and review of the literature.

AIM: Median raphe cyst are uncommon malformations of male genitalia, in which are rarely described melanin pigments or melanocytes; less than ten cases have been reported in literature. The aim of our study is to describe a rare ormations, case of pigmented median raphe cyst of the scrotum, successfully treated in our hospital. CASE EXPERIENCE: A 6-years-old boy underwent surgical removal of a melanocytic lesion of the ventral surface of the scrotum in Day Surgery regimen. He reported no surgical complication or recurrence. RESULTS: Histology showed multiple cystic nodules, lined by squamous and pluri-stratified columnar epithelium, some of which contained melanic deposits and were anti-MART-positive. DISCUSSION: Even though the first case has been reported in 1985, the etiology of median raphe cysts remains unclear. Infrequently associated with trauma or infections, these lesions seem to origin from an abnormal development of the periurethral glands or atypical closure of the median raphe. Rarely melanin pigments or melanocytes are described in the histological examination, and the cause of the pigmentation is still unknown. CONCLUSION: Median raphe cysts present a non-negligible variety of clinical presentations and histological features. Pigmented ones represent the rarest form: further studies may be necessary to clarify their pathogenesis and describe their clinical evolution. KEY WORDS: Median raphs, Male genitalia, Malformations.

The Role of KRAS Mutations in Cortical Malformation and Epilepsy Surgery: A Novel Report of Nevus Sebaceous Syndrome and Review of the Literature.

The rare nevus sebaceous (NS) syndrome (NSS) includes cortical malformations and drug-resistant epilepsy. Somatic RAS-pathway genetic variants are pathogenetic in NS, but not yet described within the brain of patients with NSS. We report on a 5-year-old boy with mild psychomotor delay. A brown-yellow linear skin lesion suggestive of NS in the left temporo-occipital area was evident at birth. Epileptic spasms presented at aged six months. EEG showed continuous left temporo-occipital epileptiform abnormalities. Brain MRI revealed a similarly located diffuse cortical malformation with temporal pole volume reduction and a small hippocampus. We performed a left temporo-occipital resection with histopathological diagnosis of focal cortical dysplasia type Ia in the occipital region and hippocampal sclerosis type 1. Three years after surgery, he is seizure-and drug-free (Engel class Ia) and showed cognitive improvement. Genetic examination of brain and skin specimens revealed the c.35G > T (p.Gly12Val) KRAS somatic missense mutation. Literature review suggests epilepsy surgery in patients with NSS is highly efficacious, with 73% probability of seizure freedom. The few histological analyses reported evidenced disorganized cortex, occasionally with cytomegalic neurons. This is the first reported association of a KRAS genetic variant with cortical malformations associated with epilepsy, and suggests a possible genetic substrate for hippocampal sclerosis.

Transcriptional profiling of medulloblastoma with extensive nodularity (MBEN) reveals two clinically relevant tumor subsets with VSNL1 as potent prognostic marker.

Medulloblastoma with extensive nodularity (MBEN) is one of the few central nervous system (CNS) tumor entities occurring in infants which is traditionally associated with good to excellent prognosis. Some MBEN, however, have been reported with an unfavorable clinical course. We performed an integrated DNA/RNA-based molecular analysis of a multi-institutional MBEN cohort (n = 41) to identify molecular events which might be responsible for variability in patients' clinical outcomes. RNA sequencing analysis of this MBEN cohort disclosed two clear transcriptome clusters (TCL) of these CNS tumors: "TCL1 MBEN" and "TCL2 MBEN" which were associated with various gene expression signatures, mutational landscapes and, importantly, prognosis. Thus, the clinically unfavorable "TCL1 MBEN" subset revealed transcriptome signatures composed of cancer-associated signaling pathways and disclosed a high frequency of clinically relevant germline PTCH1/SUFU alterations. In contrast, gene expression profiles of tumors from the clinically favorable "TCL2 MBEN" subgroup were associated with activation of various neurometabolic and neurotransmission signaling pathways, and germline SHH-pathway gene mutations were extremely rare in this transcriptome cluster. "TCL2 MBEN" also revealed strong and ubiquitous expression of VSNL1 (visinin-like protein 1) both at the mRNA and protein level, which was correlated with a favorable clinical course. Thus, combining mutational and epigenetic profiling with transcriptome analysis including VSNL1 immunohistochemistry, MBEN patients could be stratified into clinical risk groups of potential value for subsequent treatment planning.

IDO1 involvement in mTOR pathway: a molecular mechanism of resistance to mTOR targeting in medulloblastoma.

Medulloblastoma (MB) is the most common malignant brain tumor in children. Despite therapeutic advancements, high-risk groups still present significant mortality. A deeper knowledge of the signaling pathways contributing to MB formation and aggressiveness would help develop new successful therapies. The target of rapamycin, mTOR signaling, is known to be involved in MB and is already targetable in the clinical setting. Furthermore, mTOR is a master metabolic regulator able to control cell growth versus autophagy decisions in conditions of amino-acid deprivation that can be due to IDO1 enzymatic activity. IDO1 has been also implicated in the regulation of inflammation, as well as of T cell-mediated immune responses, in a variety of pathological conditions, including brain tumors. In particular, IDO1 induces expansion of regulatory T-cells (Treg), preventing immune response against tumor cells. Analysis of 27 MB tissue specimens for the expression of both mTOR and IDO1 showed their widespread expression in all samples. Testing their cooperation in vitro, a significant involvement of IDO1 in mTOR immunogenic pathway was found, able to counteract the aim of rapamycin treatment. In MB cell lines, inhibition of mTOR strongly induced IDO1 expression and activity, corroborating its ability to recruit Treg cells in the tumor microenvironment. The mTOR/IDO1 cross talk was found to be strictly specific of MB cells. We demonstrated that mTOR pathway cross talks with IDO1 pathway to promote MB immune escape, possibly contributing to failure of mTOR- targeted therapy.

Ullrich-Turner Syndrome and Tumor Risk: Is There Another Chance to Early Gonadectomy in Positive TSPY and SRY Patients?

The presence of the Y chromosome in the karyotype of patients with disorders of sex differentiation is significantly associated with an increased risk to develop specific types of malignancies, predominantly type II germ cell tumors (GCTs). Gonadoblastoma in the gonads without an obvious testicular differentiation and intratubular germ cell neoplasia of unclassified type in testicular tissue are the precursor lesions of most GCTs. Gonadal dysgenesis, the characteristic feature of Ullrich-Turner syndrome (UTS), further contributes to increase this tumor risk. The reported incidence of Y chromosome material in UTS is 6 to 8% and in these cases an early gonadectomy is strongly recommended to prevent the risk of a malignancy. The aim of this work was to retrospectively analyze the clinical outcome and the histopathological and cytogenetic findings of our UTS patients who underwent gonadectomy to establish strict selection criteria aimed at promoting an organ-sparing surgery.

Pituicytoma and Cushing's Disease in a 7-Year-Old Girl: A Mere Coincidence?

Pituicytoma is a tumor extremely rare in childhood, with only 4 cases reported in literature. It is thought to arise from the specialized glial elements called "pituicytes." The association of pituicytoma and Cushing's disease (CD) has been described only once so far, in an adult patient. A 7-year-old girl was referred for clinical signs of hypercortisolism, and a diagnosis of CD was made. MRI revealed 2 pathologic areas in the pituitary gland. The patient underwent surgery, with microscopic transsphenoidal approach, and a well-circumscribed area of pathologic tissue was identified and removed. Surprisingly, histologic and immunohistochemical study provided unequivocal evidence of pituicytoma. No pituitary adenoma could be identified. For persistent hypercortisolism, the patient necessitated transsphenoidal endoscopic reintervention and 2 other lesions were removed. By immunohistological examination, these lesions were confirmed to be corticotropin-secreting adenoma. Unfortunately, there was no postoperative decrease in corticotropin and cortisol levels, and the patient underwent bilateral laparoscopic adrenalectomy. Considering that we report a second case of association of pituicytoma and corticotropin-secreting adenoma, that CD is infrequent, and pituicytoma is extremely rare in childhood, the coexistence of these 2 tumors should not be considered a mere coincidence. To date, there is no conclusive evidence about the origin of these different subtypes of pituitary tumors. This case supports the hypothesis that these tumors share a common progenitor cell, which could be the folliculostellate cell.

Microscopic neoplastic thrombosis in localised nephroblastoma: does it influence outcome?

INTRODUCTION: Microscopic neoplastic thrombosis (MNT) is reported to occur frequently in Wilms tumour (WT). The aim of this study is to determine whether MNT influences prognosis in localised WT. PATIENTS AND METHODS: Records and slides of 80 consecutive, unselected, localised WT patients were retrospectively reviewed. All patients received chemotherapy before surgery according to SIOP Protocol. The median follow-up was 9 years (range 0.5-25.8). The Kaplan-Meier method and the Cox proportional hazard model were applied. RESULTS: MNT was present in 14 (18%) cases. Out of 14 patients with MNT, 6 presented macroscopic thrombosis and 5 had either blastemal predominance or anaplastic histology. The 5-year overall survival (OS) and progression-free survival (PFS) for the whole population were 95% (95% confidence interval, CI, 87-98%) and 91% (95% CI 82-96%), respectively. The 5-year OS and PFS for MNT positive patients were 92% (95% CI 57-99%) and 77% (95% CI 44-92%), while the 5-year OS and PFS for MNT negative patients were 96% (95% CI 87-99%) and 94% (95% CI 85-98%), respectively; the difference was statistically significant (p<0.05) for PFS. In multivariate analysis, only the presence of anaplasia retained significance with a hazard ratio (HR) of 14.8 and 12.9 (p<0.05) for recurrence and death, respectively. CONCLUSION: These data suggest that the presence of MNT increases the risk of recurrence. MNT is associated with well-known prognostic factors, such as macroscopic thrombosis (possibly representing regression of macroscopic involvement) and anaplasia. Further prospective studies are needed to clarify the role of MNT as independent prognostic factor.

Neoplastic disease and deletion 22q11.2: a multicentric study and report of two cases.

Deletion 22q11.2 is a chromosomal abnormality detected in young patients with clinical manifestations of the DiGeorge/velocardiofacial syndrome. Conotruncal heart defects are also associated with del22q11.2. An association of these cardiac malformations with neoplasias has been observed. Our series includes two cases of malignancies, a hepatoblastoma and a renal-cell carcinoma, arising in children with complex cardiac malformations. The aim of the study was to determine if the deletion at 22q11.2 was present and could be responsible for both pathological processes. Del22q11.2 was identified in both cases. Comparative genomic hybridization revealed terminal gains on chromosomes 1q and Xq and terminal loss on 1p in the hepatoblastoma, and gains in 1p, 12q, 16p, 20q, 22q, and whole chromosome 19 and loss of Xq in the renal-cell carcinoma. Our results confirm a common genetic basis for cardiac malformations, and del22q11.2 presents a risk factor for the development of pediatric tumours.

Expression of the lipogenic enzyme fatty acid synthase (FAS) in retinoblastoma and its correlation with tumor aggressiveness.

PURPOSE: Fatty acid synthase (FAS) performs the anabolic conversion of dietary carbohydrate or protein to fatty acids. Many common human cancers express high levels of FAS, and its differential expression between normal and neoplastic tissues has led to the consideration of FAS as a target for anticancer therapy. To investigate the potential of targeting FAS in the treatment of retinoblastoma, we first determined whether FAS was activated in this human tumor. Moreover, correlation of FAS expression with tumor aggressiveness was determined. METHODS: FAS reactivity was evaluated by immunohistochemistry in 66 retinoblastoma specimens from 65 patients. Degree of tumor differentiation, choroid invasion, optic nerve infiltration, mitotic rate, and necrosis extension were estimated. FAS expression was correlated with all these tumor characteristics by means of parametric and nonparametric statistical analyses. RESULTS: Eighty-two percent of tumors were FAS positive. Stronger FAS expression correlated with more advanced choroid (P < 0.001) and optic nerve (P = 0.016) invasion, high mitotic index (P < 0.001), and less differentiated histology (P = 0.047). Correlation with extension of necrosis was not statistically significant. Unaffected retina was negative. CONCLUSIONS: The data suggest that expression of FAS and fatty acid synthesis support an essential functional aspect of retinoblastoma cells, perhaps cell growth or survival. FAS activation may serve as a novel target for systemic and local antineoplastic therapy and, because it increases with tumor aggressiveness, its inhibition could represent an alternative treatment strategy in advanced and resistant retinoblastomas.

Expression of the lipogenic enzyme fatty acid synthase (FAS) as a predictor of poor outcome in nephroblastoma: an interinstitutional study.

BACKGROUND: Treatment of nephroblastoma (Wilms tumor) has presently achieved a greater than 80% cure rate. Pathologic stage and grade are considered the most reliable prognostic parameters, but other biologic factors are under study in order to improve patient stratification into risk groups. Correlation of elevated levels of the lipogenic enzyme fatty acid synthase (FAS) with aggressiveness of some cancers has drawn attention to this enzyme as a possible marker of poor prognosis. PROCEDURE: To determine the predictive strength of FAS expression in Wilms tumor (with particular emphasis on intermediate risk, i.e., non anaplastic tumors, the vast majority of nephroblastomas), we evaluated immunostaining expression in archival specimens from 94 neoplasms. The degree of expression was correlated with stage, grade, clinical course and administration of prenephrectomy chemotherapy. RESULTS: Expression of FAS increased in anaplastic tumors (P = 0.043) and higher stages (P = 0.029). FAS expression correlated with OS and DFS at both univariate and multivariate analysis. Comparable results were obtained when analyzing the intermediate risk population separately. Pretreatment resulted in an increased FAS expression, without reaching significance level (P = 0.059). CONCLUSIONS: Expression of FAS might be an independent prognostic factor, particularly for intermediate-risk patients. The blockade of fatty acid synthesis by inhibition of FAS enzymatic function by means of metabolic analogues might prove a novel target pathway for the treatment of nephroblastoma.

Expression of glial cell line-derived neurotrophic factor and neurturin in mature kidney, nephrogenic rests, and nephroblastoma: possible role as differentiating factors.

Kidney development involves a series of complex interactions between the ureteric bud and undifferentiated mesenchyme, resulting in the production of the nephron unit. Among locally derived soluble factors, a particular relevance has been recognized to glial cell line-derived neurotrophic factor (GDNF) and neurturin (NTN) for the mesenchyme-to-epithelial conversion of a metanephron. Nephroblastoma is a developmental tumor of the kidney deriving from metanephric blastema that mimics renal development and may offer an adequate model of human nephrogenesis. We investigated the immunohistochemical expression of GDNF, NTN, and their receptors (GFRalpha1, 2, and 3, and Ret) in normal human kidney and in 42 nephroblastomas, 20 of which were associated with nephrogenic rests (group A) and 22 were not (group B). We compared the immunostaining pattern in group A vs. group B and correlated clinical course with stage, grade, presence of nephrogenic rests, and immunohistochemical findings. GDNF, NTN, and their receptors were expressed in mature kidney and in 67% (GDNF) and 33% (NTN) of tumors, particularly in the epithelial component; precursor lesions were negative. No significant differences of expression were observed between groups A and B tumors. Low stage (P = 0.012), absence of nephrogenic rests (P = 0.016), intense expression of GDNF (P = 0.034), and NTN (P = 0.05) were associated with a more favorable outcome. Besides inductive activity in nephrogenesis, GDNF and NTN may play a role in maintaining differentiation and survival functions in mature kidney and may contribute to induce differentiation of nephroblastoma cells toward the less aggressive epithelial component. The pathway of activation seems to follow an autocrine/paracrine mechanism, as neurotrophic factors, GFRalpha1-2-3 receptors and Ret are coexpressed.

Nephroblastoma: multidrug-resistance P-glycoprotein expression in tumor cells and intratumoral capillary endothelial cells.

The development of chemoresistance in a variety of cancers seems related to overexpression of the P-glycoprotein (P-gp) drug pump. Nephroblastoma, the most common malignant renal tumor of childhood, usually is responsive to treatment, and prognosis is favorable in most cases. However, the disease in a subset of patients is refractory to treatment, and the disease follows an aggressive course. To study P-gp expression in this tumor and its correlation with outcome, tumor samples from 93 patients were examined by immunohistochemical analysis. P-gp expression was determined separately in both tumor cells and intratumoral capillary endothelium. The likelihood ratio test, the Kaplan-Meier method, and the log-rank test were used to evaluate its association with clinical course, grade, stage, and administration of preoperative chemotherapy. The results for the majority of nephroblastomas were variably positive; in 43 (46%) of them, newly formed capillary endothelial cells also stained positive. While no association of P-gp expression in tumor cells with clinical course, stage, and grade could be demonstrated, positivity in endothelial cells correlated significantly with unfavorable outcome, suggesting that chemoresistance depended on an active blood-tumor barrier. Previous chemotherapy induced P-gp overexpression in tumor cells.

Cystic dysplasia of the rete testis: report of two cases and review of the literature.

Cystic dysplasia of the rete testis (CDT) is a rare congenital defect, characterized by multiple irregular cystic spaces in the mediastinum of the testis that may involve the whole gonad. A review of the literature has shown 32 reported cases, the majority of which were associated with ipsilateral renal malformations (agenesis/cystic dysplasia). Pathogenesis may be attributed to an early insult involving mesonephric duct development. Although treatment is surgical, when feasible, a conservative or nonoperative approach is suggested. Here we report two cases, one in a 3-year-old boy and one in a 10-day-old newborn. Concomitant cystic dysplasia of ipsilateral kidney was present in the former patient, while CDT was the solitary finding in the latter patient. Orchiectomy was performed in both patients, for extensive gonad involvement in the older boy and for suspected gonad torsion in the newborn patient.

Nephroblastoma. DNA characteristics and their modifications induced by prenephrectomy chemotherapy: a cytofluorimetric study.

Treatment of nephroblastoma (Wilms' tumor) has presently achieved a 90% survival rate. Stage and grade are considered the most reliable prognostic parameters, but other biological factors are under study in order to improve patient stratification. Deoxyribonucleic acid (DNA) ploidy has been suggested to be useful in this setting. We retrospectively studied 79 patient with nephroblastoma (58 pretreated with chemotherapy and 21 not pretreated) by means of flow cytometry. DNA content and synthetic phase values were correlated with pathologic features and outcome. DNA modifications induced by chemotherapy were investigated. Sixty-nine tumors were diploid and 10 aneuploid. DNA content did not correlate with clinical course and was not modified by pretreatment. Aneuploid tumors were restricted to lower stages. Mean S-phase rate was lower and did not vary according to histology in pretreated tumors, while it was higher and increased with grade (p = 0.007) in previously untreated tumors. The fraction of cells in synthetic activity was related to outcome: Patients whose tumors displayed higher S-phase rates had a more favorable clinical course. Ploidy did not appear to be of prognostic significance. S-phase rate decreased after chemotherapy (p = 0.0002) and was related to survival. The worse outcome of pretreated patients might be attributed to a minor sensitivity to postoperative treatment: Preoperative chemotherapy would decrease the cell proliferation and might select resistant cellular clones of (possible) neoplastic residues.