We investigated 17 children with nephrotic syndrome (NS) of early onset (14 aged < 1 year) and rapid progression to end-stage renal disease for the presence of mutations in the Wilms' tumor suppressor gene WT1 on chromosome 11. In eight children (7 genotypic males) an association with Wilms' tumor and/or ambiguous genitalia (Denys-Drash syndrome) was observed. In these eight and two additional female patients with NS only constitutional missense mutations in the WT1 gene were detected; four children presented the so-called hot spot mutation in exon 9 (R394N) and six had different mutations in exons 8 and 9 (4 not previously described). Renal biopsy showed diffuse mesangial sclerosis in eight and focal segmental sclerosis in two cases. End-stage renal disease was reached either concomitantly or within four months after onset of NS in seven of ten patients. A unilateral Wilms' tumor was found before or concomitant with NS in four children (3 males, 1 female). From the seven genotypic males with WT1 mutations, five presented ambiguous genitalia and two a female phenotype. No mutation of the WT1 gene was found in seven other children with isolated congenital or infantile NS with or without DMS who appeared to have a slower progression than the first group. It is proposed that patients with early onset, rapidly progressive NS and diffuse mesangial or focal segmental sclerosis should be tested for WT1 mutations to identify those at risk for developing Wilms' tumor.

Hypoxia-inducible factor 1 (HIF-1) controls angiogenesis and glycolysis, two leading characteristics of solid tumor invasion, metastasis, and lethality. Increased angiogenesis is also found in the bone marrow (BM) of leukemias. Less is known in leukemia about the role of HIF-1 and vascular endothelial growth factor (VEGF), the most important proangiogenic target gene of HIF-1. We show by immunohistochemistry that the oxygen-regulated component of HIF-1 (HIF-1a) is overexpressed in clusters of leukemic cells in BM specimens of childhood acute lymphoblastic leukemia (ALL) and absent in biopsies of normal BM. Half the HIF-1a-positive ALL biopsies exhibited VEGF coexpression. Among 96 children with relapsed ALL, diagnostic BM aspirates with high VEGF mRNA levels were associated with a significantly lower probability of eventfree survival at 3 years (0.3170.08 vs 0.6570.07, P ¼ 0.003). Those with poor molecular response to therapy (evaluated by MRD assessment) had 2.2-fold higher VEGF levels than those responding well to chemotherapy (P ¼ 0.005). In conclusion, the data demonstrate activation of the HIF pathway in the BM of ALL patients and indicate that the expression of HIF target genes, such as VEGF, play an important role in leukemia progression, therapy response, and outcome.

According to this study and the current literature in the field of hamartomas and some neoplasia, we can assume that increased growth factor expression plays a role in the formation of chorioangiomas, since it stimulates proliferation in a wide variety of cell compartments.

We report on a case of absent pulmonary valve syndrome in a woman with a history of one healthy child and one child with tetralogy of Fallot with absent pulmonary valve. The diagnosis was missed at the first ultrasound examination performed at 13 + 5 weeks of gestation and correctly diagnosed at 21 + 5 weeks. Re-evaluation of the ultrasound examination recorded at 13 + 5 weeks exhibited severe insufficiency of the pulmonary valve at this time. However, neither dilatation of the right and left pulmonary arteries nor asymmetry of the ventricles were present at that time. The pregnancy was terminated at 22 + 1 weeks of gestation when autopsy confirmed the diagnosis of absent pulmonary valve syndrome. Karyotyping of the fetus after termination of pregnancy revealed normal chromosomes. Echocardiography of the parents and the healthy sibling revealed normal results.

Chorioangiomas occur in 0.61% of pregnancies, they are mainly microscopically small, and 55% of them are localized subchorial. The rate of their occurrence rises almost linearly with maternal age; chorioangiomas are found most often in women who are over 30 years old. Hypertension and diabetes are found more often in combination with chorioangiomas than they are in otherwise normal pregnancies. In 72% of all cases girls were born; in 33% we also observed malfunctions in the maturation processes of the placental parenchyma, in particular arrested and delayed maturation of the villi. Premature births occur approximately three times more often in chorioangioma pregnancies than in normal ones. Chorioangiomas are often found in primipara and twin pregnancies.