In vitro efficacy of ARQ 092, an allosteric AKT inhibitor, on primary fibroblast cells derived from patients with PIK3CA-related overgrowth spectrum (PROS).

Postzygotic mutations of the PIK3CA [phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha] gene constitutively activate the PI3K/AKT/mTOR pathway in PIK3CA-related overgrowth spectrum (PROS) patients, causing congenital mosaic tissue overgrowth that even multiple surgeries cannot solve. mTOR inhibitors are empirically tested and given for compassionate use in these patients. PROS patients could be ideal candidates for enrolment in trials with PI3K/AKT pathway inhibitors, considering the "clean" cellular setting in which a unique driver, a PIK3CA mutation, is present. We aimed to assess the effects of blocking the upstream pathway of mTOR on PROS patient-derived cells by using ARQ 092, a potent, selective, allosteric, and experimental orally bioavailable and highly selective AKT-inhibitor with activity and long-term tolerability, currently under clinical development for treatment of cancer and Proteus syndrome. Cell samples (i.e., primary fibroblasts) were derived from cultured tissues obtained from six PROS patients [3 boys, 3 girls; aged 2 to 17 years] whose spectrum of PIK3A-related overgrowth included HHML [hemihyperplasia multiple lipomatosis; n = 1], CLOVES [congenital lipomatosis, overgrowth, vascular malformations, epidermal nevi, spinal/skeletal anomalies, scoliosis; n = 1], and MCAP [megalencephaly capillary malformation syndrome; n = 4]. We performed the following: (a) a deep sequencing assay of PI3K/AKT pathway genes in the six PROS patients' derived cells to identify the causative mutations and (b) a pathway analysis to assess the phosphorylation status of AKT [Ser473 and Thr308] and its downstream targets [pAKTS1 (Thr246), pRPS6 (Ser235/236), and pRPS6Kß1 (Ser371)]. The anti-proliferative effect of ARQ 092 was tested and compared to other PI3K/AKT/mTOR inhibitors [i.e., wortmannin, LY249002, and rapamycin] in the six PROS patient-derived cells. Using ARQ 092 to target AKT, a critical node connecting PI3K and mTOR pathways, we observed the following: (1) strong anti-proliferative activity [ARQ 092 at 0.5, 1, and 2.5 µM blunted phosphorylation of AKT and its downstream targets (in the presence or absence of serum) and inhibited proliferation after 72 h; rapamycin at 100 nM did not decrease AKT phosphorylation] and (2) less cytotoxicity as compared to rapamycin and wortmannin. We demonstrated the following: (a) that PROS cells are dependent on AKT; (b) the advantage of inhibiting the pathway immediately downstream of PI3K to circumventing problems depending on multiple classes a PI3K kinases; and (c) that PROS patients benefit from inhibition of AKT rather than mTOR. Clinical development of ARQ 092 in PROS patients is on going in these patients.

A gene for Hirschsprung disease maps to the proximal long arm of chromosome 10.

Hirschsprung disease (HSCR) is a frequent congenital disorder (1 in 5,000 newborns) of unknown origin characterized by the absence of parasympathetic intrinsic ganglion cells of the hindgut. Taking advantage of a proximal deletion of chromosome 10q (del 10q11.2-q21.2) in a patient with total colonic aganglionosis, and of a high-density genetic map of microsatellite DNA markers, we performed genetic linkage analysis in 15 non-syndromic long-segment and short-segment HSCR families. Multipoint linkage analysis indicated that the most likely location for a HSCR locus is between loci D10S208 and D10S196, suggesting that a dominant gene for HSCR maps to 10q11.2, a region to which other neural crest defects have been mapped.

Scoliosis with cognitive impairment in a girl with 8q11.21q11.23 microdeletion and SNTG1 disruption.

Idiopathic scoliosis (IS) is an abnormality of the vertebral column with a spine curvature of at least 10 degrees. It is the most common spinal deformity in children with a prevalence of 2%-3%, and its aetiology is unknown. Genetic factors are known to play a role and a number of linkage analyses showed associations of various loci. Here we describe a new case of a de novo interstitial deletion 8q11.21q11.2 disrupting SNTG1 gene, identified by array-CGH in a girl with cognitive impairment and a scoliosis that 'appears' like to IS. SNTG1 encodes γ-1 Syntrophin protein that is part of the dystrophin associated protein complex and interacts directly with the C-terminal of dystrophin. Its expression is restricted to neurons and particularly in those areas of the brain that have been suggested to affect postural control. The involvement of SNTG1 gene in IS was already been reported in a family with a breakpoint between exons 10 and 11. Mutational analysis of SNTG1 exons in 152 sporadic IS patients had revealed changes in three patients. In conclusion, our data add a further line of evidence suggesting SNTG1 could represent an interesting candidate for its involvement in scoliosis.

Prevention strategies for severe hemoglobinopathies in endemic and nonendemic immigration countries: the Latium example.

OBJECTIVE: To review prevention data for hemoglobinopathies from Latium, a large Italian region with a considerable immigrant population and with a well-established regional prevention program. METHOD: All data pertaining to population screening for hemoglobinopathies in the Latium region were reviewed for the period 1994-2007. Screening was performed universally in secondary schools and to pregnant couples at the time of prenatal care. We have examined the trends in positive screening results as well as the type of hemoglobinopathies detected during the study period, and we have correlated them to the type of population (immigrant vs indigenous). RESULTS: From 1994 to 2007, 167 235 individuals were examined for carrier status for hemoglobinopathies, and 10 353 of them (6.2%) were immigrants. We have registered a threefold increase in rates of screen-positive subjects who belonged to ethnic minorities during the study period (from 2.7% in 1994 to 9.8% in 2007). Over half of the screen-positive subjects (5397/10 353) presented no hematological anomalies, 24% (n = 2472) had iron deficiency, and 24% (n = 2484) was classified as putative carriers. Among the last group, 22.6% were carriers of beta-thalassemia, 48% were suspected alpha-thalassemia carriers, and the remainder had less common hemoglobinopathies. While the prevention program resulted in nearly zero births of autochthonous newborns affected by severe hemoglobinopathies, a rise in number of affected individuals was noted among immigrants. Screening of secondary school students was accepted by 67% of immigrant parents, resulting in 9737 pupils screened between 2002 and 2006. CONCLUSION: Existing preventive programs for severe hemoglobinopathies should adapt to changes in population ethnicities. Screening for hemoglobinopathies at school age is an efficient strategy.

Search for pathogenetic variants of the SPRY2 gene in intestinal innervation defects.

SPRY2 is an inducible inhibitor of signalling mediated by tyrosine kinases receptors, whose targeting causes intestinal hyperganglionosis in mice. In this light, we have undertaken a mutational analysis of the SPRY2 gene in patients affected with intestinal neuronal dysplasia (IND), without detecting nucleotide changes in any of the 26 DNA samples analysed, with the exception of two already known polymorphic variants. A role of the SPRY2 gene in IND pathogenesis can be thus excluded.

Common mutations in autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy patients of different origins.

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED; OMIM *240300, also called APS 1,) is a rare autosomal recessive disorder that is more frequent in certain isolated populations. It is generally characterized by two of the three major clinical symptoms that may be present, Addison's disease and/or hypoparathyroidism and/or chronic mucocutaneous candidiasis. Patients may also have a number of other clinical symptoms including chronic gastritis, gonadal failure, and rarely, autoimmune thyroid disease and insulin-dependent diabetes mellitus. We and others have recently identified the gene for APECED, which we termed AIRE (for autoimmune regulator). AIRE is expressed in thymus, lymph nodes, and fetal liver and encodes a protein containing motifs suggestive of a transcriptional regulator, including two zinc finger motifs (PHD finger), a proline-rich region, and three LXXLL motifs. Six mutations, in cluding R257X, the predominant Finnish APECED allele, have been defined. R257X was also observed in non-Finnish APECED patients occurring on different chromosomal haplotypes suggesting different mutational origins. Here we present mutation analyses in an extended series of patients, mainly of Northern Italian origin. We have detected 12 polymorphisms, including one amino acid substitution, and two additional mutations, R203X and X546C, in addition to the previously described mutations, R257X, 1096-1097insCCTG, and a 13-bp deletion (1094-1106del). R257X was also the common mutation in the Northern Italian patients (10 of 18 alleles), and 1094-1106del accounted for 5 of 18 Northern Italian alleles. Both R257X and 1094-1106del were both observed in patients of four different geo-ethnic origins, and both were associated with multiple different haplotypes using closely flanking polymorphic markers showing likely multiple mutation events (six and four, respectively). The identification of common AIRE mutations in different APECED patient groups will facilitate its genetic diagnosis. In addition, the polymorphisms presented provide the tools for investigation of the involvement of AIRE in other autoimmune diseases, particularly those affecting the endocrine system.

Heterogeneity and low detection rate of RET mutations in Hirschsprung disease.

Mutations in some exons of the RET proto-oncogene were recently observed in Hirschsprung patients. Using DNA polymorphisms and single-strand conformation polymorphism analysis for the whole coding sequence of the RET proto-oncogene, 82 unrelated Hirschsprung patients were screened systematically. A total of 4 complete deletions of RET and 12 point mutations were identified, each present in no more than one patient and distributed along the whole gene. De novo mutations could be documented in 4 patients. Southern blot and fluorescence in situ hybridization analysis carried out in a restricted number of patients did not reveal any deletion of RET. The low efficiency in detecting mutations of RET in Hirschsprung patients (20%) may originate mainly from genetic heterogeneity.

Uncombable hair, retinal pigmentary dystrophy, dental anomalies, and brachydactyly: report of a new patient with additional findings.

A new ectodermal dysplasia syndrome was reported by Bork et al. in 1987 (Hautarzt 38:342-347). The syndrome consisted of hypotrichosis with the typical SEM (scanning electron microscopy) changes of uncombable hair, retinal pigmentary dystrophy, juvenile cataract, oligodontia, brachydactyly with brachymetacarpia; it was inherited as an autosomal dominant trait. We describe a sporadic case and add further clinical findings to expand the spectrum of this rare syndrome.

Congenital diaphragmatic hernia associated with ipsilateral upper limb reduction defects: report of a case with thumb hypoplasia.

Four unrelated cases of congenital diaphragmatic hernia associated with ipsilateral upper limb reduction defects were reported by McCredie and Reid in 1978 (J Pediatr 92: 762-765). As contiguous segments of the cervical neural crest are involved in the development of diaphragm and arms, the authors suggested that an early injury to the cervical neural crest might be the common underlying pathogenesis. We describe here a further example of this malformation complex: a newborn with a left posterolateral diaphragmatic hernia associated with ipsilateral thumb hypoplasia.

Ectodermal abnormalities in Kabuki syndrome.

We describe a girl with Niikawa-Kuroki (Kabuki) syndrome (NKS) with conical incisors, hypodontia, hypoplastic nails, and brittle hair. Abnormal teeth are common in NKS and support a hypothesis of autosomal dominant inheritance of the syndrome [Halal et al., 1989; Silengo et al., 1996]. Hair abnormalities have never been investigated in NKS. The ectodermal involvement in NKS could represent an important clue for the understanding of the pathogenesis of this syndrome.

Fontaine-Farriaux craniosynostosis: second report in the literature.

Craniosynostosis is determined by the precocious fusion of one or more calvarial sutures leading to an abnormal skull shape. Additionally, nodular heterotopia is a disorder of neuronal migration and/or proliferation. We describe a very rare multiple congenital anomalies (MCA) syndrome in which craniosynostosis is associated with bilateral periventricular nodular heterotopia (BPNH) of the gray matter and other malformations involving hands, feet, and the gut. Clinical findings and further investigations suggest the diagnosis of craniosynostosis Fontaine-Farriaux type. To the best of our knowledge, this case is only the second report of this MCA syndrome. Based on the clinical and radiological data of the two cases reported, we hypothesize that this malformative complex may be considered a new BPNH/MCA syndrome and propose to classify it as BPNH/craniosynostosis. Previous studies demonstrated that at least two BPNH/MCA syndromes have been mapped to the Xq28 chromosomal region in which a causative gene for isolated BPNH is located. The same authors hypothesized that other BPNH syndromes could be due to microrearrangements at the same Xq28 region. Our case presents several overlapping features with some BPNH/MCA syndromes and it is possible that this new complex disorder may be caused by rearrangements at the same chromosomal region that could alter expression of different genes in Xq28.

Congenital hypoplastic anaemia in a patient with a new multiple congenital anomalies-mental retardation syndrome.

We report on a girl with congenital hypoplastic anaemia, "coarse" face, generalized hypertrichosis with scalp hypotrichosis, short fifth finger, hypoplastic toenails, and mental retardation. A sister of the proposita, who died at the age of 1 year, had severe congenital anaemia, hypoplastic fingernails, low birth weight, failure to thrive, and repeated upper respiratory tract infections. Based on family history, we suspect that hypoplastic anaemia and the same multiple congenital anomalies-mental retardation syndrome (MCA/MR) were also present in this sister. To the best of our knowledge, this patient represents the first report of congenital hypoplastic anaemia and such a complex MCA/MR syndrome, probably inherited as an autosomal recessive trait.

Severe end of Opitz trigonocephaly (C) syndrome or new syndrome?

We report on four unrelated cases of an Opitz trigonocephaly (C)-like syndrome with a highly characteristic combination of facial anomalies including prominent metopic suture, exophthalmos, hypertelorism, cleft lip and palate, flexion deformities of the upper limbs and multiple other anomalies. We also review two very similar published cases formerly considered to have the C syndrome. Although there is overlap, a clinical distinction from the Opitz trigonocephaly and other syndromes seems possible, and thus a specific causal entity may be postulated.

The genetics of anorectal malformations: a complex matter.

Because the spectrum of anorectal malformations is wide, genetic investigations of these anomalies should include the study of multigenic models presenting variable penetrance and expressivity. Current knowledge in clinical genetics, cytogenetics, and molecular genetics of anorectal anomalies are reviewed. The analysis of associated anomalies (that are found in more than 60% of anorectal malformations) is an important aspect of the molecular study, because the association of anomalies with mendelian transmission or with a recognized causative gene can be an essential starting point for further investigations. In the present study, the authors focus on associated sacral anomalies, urethral malformations, and intestinal dysganglionoses. In particular, associated sacral anomalies could be a partial expression of the Currarino syndrome, which represents the only association for which genetic evidence has been demonstrated by linkage analysis. The authors studied a four-generation pedigree with recurrence of the Currarino syndrome, and the haplotype reconstruction confirmed that the gene segregating in this family is located in the 7q36 region. The collection and study of families with multiple cases of anorectal malformations could show whether different phenotypes are caused by single genes.

Pathogenesis of Hirschsprung's disease.

Hirschsprung's disease is an inherited disorder showing incomplete penetrance and variable expressivity. Genetic mapping and mutation screening of candidate genes, together with the study of several natural and knockout animal models, clearly have shown the involvement of several different genes in the pathogenesis of Hirschsprung's disease. Among these genes, the RET proto-oncogene accounts for the highest proportion of both familial and sporadic cases, with a wide range of mutations scattered along its entire coding region. The low detection rate of RET mutations in Hirschsprung patients also led to different hypotheses, such as the existence of additional Hirschsprung genes. Different animal and human genetic studies have identified 6 Hirschsprung genes: RET proto-oncogene (RET), endothelin 3 (EDN3), endothelin B receptor gene (EDNRB), glial-cell-line-derived neurotrophic factor (GDNF), endothelin converting enzyme (ECE1), gene encoding the Sry-related transcription factor SOX10 (SOX10). Microenvironmental factors also can play a role in the pathogenesis of aganglionosis. The developmental process of the crest-derived progenitor cells is sensitive to the level of different molecules. The expression deficit of different factors (GDNF, NTN) in the hindgut, in the absence of genetic mutations, could determine a missed activation of the receptor system, causing enteric neuroblast migration arrest.

Neuronal intestinal dysplasia: clinical experience in Italian patients.

The authors present a review of 431 children biopsied and studied with the following histochemical and immunohistochemical techniques: 1) acetylcholinesterase activity; 2) alphanaphthylesterase activity; 3) S-100 protein immunohistochemical technique; 4) glyoxylic acid method. Two hundred forty-eight patients of our series presented different forms of dysganglionosis, 12 of them (4.8%) presenting neuronal intestinal dysplasia type B. In 7 cases, NID type B was diffuse, whereas in 5 recto-colonic NID type B was confined to the splenic flexure. Male:female ratio was 9:3. Familial recurrence was present in 2 of the 12 cases of our series, affected by severe neuronal intestinal dysplasia extended to the small intestine, associated with intestinal malrotation and short bowel syndrome. Four of the 7 cases of diffuse NID type B and 2 of the 5 cases of rectocolonic NID type B were surgically treated. Three patients with diffuse NID died from sepsis within the 2nd year of life. This study confirms that NID type B is a form of dysganglionosis which can be diagnosed in a Mediterranean country if histochemical techniques are applied in the study of a large series of constipated and pseudo-Hirschsprung patients. From a pathogenetic point of view, the authors compared the histochemical findings of biopsies from their series of NID patients with those of recto-colonic biopsies from patients with MEN II B syndrome. The similarity of GI symptoms in MEN II B and NID pediatric patients suggests that the two disorders could be the result of mutations affecting the same domain of the RET proto-oncogene.

New clinical findings in oculo-ectodermal syndrome.

We report a 2-year-old male with aplasia cutis congenita of the scalp, epibulbar dermoids, strabismus and macrocephaly. In our opinion, he is affected by the Oculo-Ectodermal syndrome first described by Toriello et al. (1993). Am J Med Genet 45:764-766]. This is the sixth report of patients with this rare entity. Our case further expands the clinical spectrum of the syndrome to include mental retardation, seizures and microscopic hair changes.

Auriculo-condylar syndrome or new syndrome?

We describe a girl with peculiar auricular dysmorphism, renal agenesis and supernumerary rib. Some different diagnostic hypotheses are discussed.

Question mark ears, temporo-mandibular joint malformation and hypotonia: auriculo-condylar syndrome or a distinct entity?

We report a boy with prominent, peculiarly malformed ears, abnormality of the ramus of the mandible and hypotonia. An isolated peculiar bilateral ear deformity named 'question mark ear' has been delineated in plastic reconstruction surgery reviews [Cosman et al., 1970 Plast Reconstr Surg 46:454-457; Cosman (1984) Plast Reconstr Surg 73:572-576; Takato et al. (1989) Ann Plast Surg 22:69-73; Brodovsky (1997) Plast Reconstr Surg 100:1254-1257; Park (1998) Plast Reconstr Surg 101:1620-1623; Al-Quattan (1998) Plast Reconstr Surg 102:439-441] and a similar deformity of the ear and changes in the temporo-mandibular joint and condyle has been described by Jampol et al. [(1998) Am J Med Genet 75:449-452] and by Guion-Almeida et al. [(1999) Am J Med Genet 86:130-133]. The present case may be the third description of this malformation complex with additional clinical features characterized by hypotonia and mild developmental delay, or possibly a new distinct entity.

[Genomic imprinting and human pathology. I. General Part]. / Imprinting genomico e patologia umana. I-Parte Generale.

Genetical as well as experimental embryology methods have permitted to uncover a very important feature of mammalian embryonic development: it has been shown that female and male genomic complements are differentially imprinted in such a way that contribution of both a maternally and a paternally derived genome are absolutely necessary for the embryo to complete its normal development. The paternal and maternal genomes are not equivalent and have a complementary role during development in mammals. The differences in activity of each parental genome result from an epigenetic modification of the genome during gametogenesis: the parental imprinting. The recent discovery of several mouse and human genes which are imprinted should permit to address new data of some diseases.