ALEXSANDRA CHRISTIANNE MALAQUIAS DE MOURA RIBEIRO
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- Rare variants in SOS2 and LZTR1 are associated with Noonan syndrome(2015) YAMAMOTO, Guilherme Lopes; AGUENA, Meire; GOS, Monika; HUNG, Christina; PILCH, Jacek; FAHIMINIYA, Somayyeh; ABRAMOWICZ, Anna; CRISTIAN, Ingrid; BUSCARILLI, Michelle; NASLAVSKY, Michel Satya; MALAQUIAS, Alexsandra C.; ZATZ, Mayana; BODAMER, Olaf; MAJEWSKI, Jacek; JORGE, Alexander A. L.; PEREIRA, Alexandre C.; KIM, Chong Ae; PASSOS-BUENO, Maria Rita; BERTOLA, Debora RomeoBackground Noonan syndrome is an autosomal dominant, multisystemic disorder caused by dysregulation of the RAS/mitogen activated protein kinase (MAPK) pathway. Heterozygous, pathogenic variants in 11 known genes account for approximately 80% of cases. The identification of novel genes associated with Noonan syndrome has become increasingly challenging, since they might be responsible for very small fractions of the cases. Methods A cohort of 50 Brazilian probands negative for pathogenic variants in the known genes associated with Noonan syndrome was tested through whole-exome sequencing along with the relatives in the familial cases. Families from the USA and Poland with mutations in the newly identified genes were included subsequently. Results We identified rare, segregating or de novo missense variants in SOS2 and LZTR1 in 4% and 8%, respectively, of the 50 Brazilian probands. SOS2 and LZTR1 variants were also found to segregate in one American and one Polish family. Notably, SOS2 variants were identified in patients with marked ectodermal involvement, similar to patients with SOS1 mutations. Conclusions We identified two novel genes, SOS2 and LZTR1, associated with Noonan syndrome, thereby expanding the molecular spectrum of RASopathies. Mutations in these genes are responsible for approximately 3% of all patients with Noonan syndrome. While SOS2 is a natural candidate, because of its homology with SOS1, the functional role of LZTR1 in the RAS/MAPK pathway is not known, and it could not have been identified without the large pedigrees. Additional functional studies are needed to elucidate the role of LZTR1 in RAS/MAPK signalling and in the pathogenesis of Noonan syndrome.
- Multigene Sequencing Analysis of Children Born Small for Gestational Age With Isolated Short Stature(2019) FREIRE, Bruna L.; HOMMA, Thais K.; FUNARI, Mariana F. A.; LERARIO, Antonio M.; VASQUES, Gabriela A.; MALAQUIAS, Alexsandra C.; ARNHOLD, Ivo J. P.; JORGE, Alexander A. L.Context: Patients born small for gestational age (SGA) who present with persistent short stature could have an underlying genetic etiology that will account for prenatal and postnatal growth impairment. We applied a unique massive parallel sequencing approach in cohort of patients with exclusively nonsyndromic SGA to simultaneously interrogate for clinically substantial genetic variants. Objective: To perform a genetic investigation of children with isolated short stature born SGA. Design: Screening by exome (n = 16) or targeted gene panel (n = 39) sequencing. Setting: Tertiary referral center for growth disorders. Patients and Methods: We selected 55 patients born SGA with persistent short stature without an identified cause of short stature. Main Outcome Measures: Frequency of pathogenic findings. Results: We identified heterozygous pathogenic or likely pathogenic genetic variants in 8 of 55 patients, all in genes already associated with growth disorders. Four of the genes are associated with growth plate development, IHH (n = 2), NPR2 (n = 2), SHOX (n = 1), and ACAN (n = 1), and two are involved in the RAS/MAPK pathway, PTPN11 (n = 1) and NF1 (n = 1). None of these patients had clinical findings that allowed for a clinical diagnosis. Seven patients were SGA only for length and one was SGA for both length and weight. Conclusion: These genomic approaches identified pathogenic or likely pathogenic genetic variants in 8 of 55 patients (15%). Six of the eight patients carried variants in genes associated with growth plate development, indicating that mild forms of skeletal dysplasia could be a cause of growth disorders in this group of patients.
- Noonan syndrome patients beyond the obvious phenotype: A potential unfavorable metabolic profile(2021) NORONHA, Renata M.; VILLARES, Sandra M. F.; TORRES, Natalia; QUEDAS, Elisangela P. S.; HOMMA, Thais Kataoka; ALBUQUERQUE, Edoarda V. A.; MORAES, Michelle B.; FUNARI, Mariana F. A.; BERTOLA, Debora R.; JORGE, Alexander A. L.; MALAQUIAS, Alexsandra C.Noonan syndrome (NS) and NS related disorders (NRD) are frequent monogenic diseases. Pathogenic variants in PTPN11 are observed in approximately 50% of these NS patients. Several pleiotropic phenotypes have previously been described in this condition. This study aimed at characterizing glucose and lipid profiles in patients with NS/NRD. We assessed fasting blood glucose, insulin, cholesterol (total and fractions), and triglyceride (TG) levels in 112 prepubertal children and 73 adults. Additionally, an oral glucose tolerance test (OGTT) was performed in 40 children and 54 adults. Data were analyzed between age groups according to the presence (+) or absence (-) of PTPN11 mutation. Prepubertal patients with NS/NRD were also compared with a control group. Despite the lean phenotype of children with NS/NRD, they presented an increased frequency of low HDL-cholesterol (63% in PTPN11+, 59% in PTPN11- and 16% in control, p < .001) and high TG levels (29% in PTPN11+, 18% in PTPN11- and 2.3% in control). PTPN11+ patients had a higher median HOMA-IR (1.0, ranged from 0.3 to 3.2) in comparison with PTPN11- (0.6; 0.2 to 4.4) and controls (0.6; 0.4 to 1.4, p = .027). Impaired glucose tolerance was observed in 19% (10:54) of lean adults with NS/NRD assessed by OGTT. Moreover, women with PTPN11 mutations had lower HDL-cholesterol levels than those without. Our results suggest that children and young adult patients with NS/NRD have an unfavorable metabolic profile characterized by low HDL, a tendency of elevated TGs, and glucose metabolism impairment despite a lean phenotype.
- Growth and Clinical Characteristics of Children with Floating-Harbor Syndrome: Analysis of Current Original Data and a Review of the Literature(2020) HOMMA, Thais K.; FREIRE, Bruna L.; HONJO, Rachel; DAUBER, Andrew; FUNARI, Mariana F. A.; LERARIO, Antonio M.; ALBUQUERQUE, Edoarda V. A.; VASQUES, Gabriela A.; BERTOLA, Debora R.; KIM, Chong A.; MALAQUIAS, Alexsandra C.; JORGE, Alexander A. L.Background: Floating-Harbor syndrome (FHS) is a rare condition characterized by dysmorphic facial features, short stature, and expressive language delay. Objective: The aim of this study was to describe a cohort of patients with FHS and review the literature about the response to recombinant human growth hormone (rhGH) therapy. Methods: Anthropometric and laboratory data from 7 patients with FHS were described. The molecular diagnosis was established by multigene analysis. Moreover, we reviewed the literature concerning patients with FHS treated with rhGH. Results: All 7 patients were born small for gestational age. At first evaluation, 6 patients had a height standard deviation score (SDS) <=-2 and 1 had short stature in relation to their target height. Bone age was usually delayed, which rapidly advanced during puberty. Nonspecific skeletal abnormalities were frequently noticed, and normal to elevated plasma IGF-I levels were observed in all except 1 patient with growth hormone deficiency. Information about 20 patients with FHS treated with rhGH was analyzed (4 from our cohort and 16 from the literature). The median height changes during the treatment period (approx. 2.9 years) were 1.1 SDS (range from -0.4 to 3.1). Nontreated patients had an adult height SDS of -4.1 +/- 1.2 (n = 10) versus -2.6 +/- 0.8 SDS (n = 7, p 0.012) for treated patients. Conclusion: We observed a laboratory profile compatible with IGF-1 insensitivity in some patients with FHS. Nevertheless, our study suggests that children with FHS may be considered as candidates for rhGH therapy. Further studies are necessary to establish the real benefit and safety of rhGH therapy in these patients.
- Tegumentary manifestations of Noonan and Noonan-related syndromes(2013) QUAIO, Caio Robledo D'Angioli Costa; ALMEIDA, Tatiana Ferreira de; BRASIL, Amanda Salem; PEREIRA, Alexandre C.; JORGE, Alexander A. L.; MALAQUIAS, Alexsandra C.; KIM, Chong Ae; BERTOLA, Debora RomeoOBJECTIVES: Noonan and Noonan-related syndromes are common autosomal dominant disorders with neuro-cardio-facial-cutaneous and developmental involvement. The objective of this article is to describe the most relevant tegumentary findings in a cohort of 41 patients with Noonan or Noonan-related syndromes and to detail certain aspects of the molecular mechanisms underlying ectodermal involvement. METHODS: A standard questionnaire was administered. A focused physical examination and a systematic review of clinical records was performed on all patients to verify the presence of tegumentary alterations. The molecular analysis of this cohort included sequencing of the following genes in all patients: PTPN1, SOS1, RAF1, KRAS, SHOC2 and BRAF. RESULTS: The most frequent tegumentary alterations were xeroderma (46%), photosensitivity (29%), excessive hair loss (24%), recurrent oral ulcers (22%), curly hair (20%), nevi (17%), markedly increased palmar and plantar creases (12%), follicular hyperkeratosis (12%), palmoplantar hyperkeratosis (10%), cafe-au-lait spots (10%) and sparse eyebrows (7%). Patients with mutations in PTPN11 had lower frequencies of palmar and plantar creases and palmar/plantar hyperkeratosis compared with the other patients. CONCLUSIONS: We observed that patients with mutations in genes directly involved in cell proliferation kinase cascades (SOS1, BRAF, KRAS and RAF1) had a higher frequency of hyperkeratotic lesions compared with patients with mutations in genes that have a more complex interaction with and modulation of cell proliferation kinase cascades (PTPN11).
- KRAS gene mutations in Noonan syndrome familial cases cluster in the vicinity of the switch II region of the G-domain: Report of another family with metopic craniosynostosis(2012) BRASIL, Amanda S.; MALAQUIAS, Alexsandra C.; KIM, Chong A.; KRIEGER, Jose Eduardo; JORGE, Alexander A. L.; PEREIRA, Alexandre C.; BERTOLA, Debora R.Noonan syndrome (NS) and Noonan-related disorders [cardio-facio-cutaneous (CFC), Costello, Noonan syndrome with multiple lentigines (NS-ML), and neurofibromatosis-Noonan syndromes (NFNS)] are a group of developmental disorders caused by mutations in genes of the RAS/MAPK pathway. Mutations in the KRAS gene account for only a small proportion of affected Noonan and CFC syndrome patients that present an intermediate phenotype between these two syndromes, with more frequent and severe intellectual disability in NS and less ectodermal involvement in CFC syndrome, as well as atypical clinical findings such as craniosynostosis. Recently, the first familial case with a novel KRAS mutation was described. We report on a second vertical transmission (a mother and two siblings) with a novel mutation (p.M72L), in which the proband has trigonocephaly and the affected mother and sister, prominent ectodermal involvement. Metopic suture involvement has not been described before, expanding the main different cranial sutures which can be affected in NS and KRAS gene mutations. The gene alteration found in the studied family is in close proximity to the one reported in the other familial case (close to the switch II region of the G-domain), suggesting that this specific region of the gene could have less severe effects on intellectual ability than the other KRAS gene mutations found in NS patients and be less likely to hamper reproductive fitness. (c) 2012 Wiley Periodicals, Inc.
- Impact of Growth Hormone Therapy on Adult Height in Patients with PTPN11 Mutations Related to Noonan Syndrome(2019) MALAQUIAS, Alexsandra C.; NORONHA, Renata M.; SOUZA, Thaiana T. O.; HOMMA, Thais K.; FUNARI, Mariana F. A.; YAMAMOTO, Guilherme L.; SILVA, Fernanda Viana; MORAES, Michelle B.; HONJO, Rachel S.; KIM, Chong A.; NESI-FRANCA, Suzana; CARVALHO, Julienne A. R.; QUEDAS, Elisangela P. S.; BERTOLA, Debora R.; JORGE, Alexander A. L.Objectives: The aim of this study was to evaluate the response to recombinant human growth hormone (rhGH) treatment in patients with Noonan syndrome (NS). Materials and Methods: Forty-two patients (35 PTPN11+) were treated with rhGH, and 17 were followed-up until adult height. The outcomes were changes in growth velocity (GV) and height standard deviation scores (SDS) for normal (height-CDC SDS) and Noonan standards (height-NS SDS). Results: The pretreatment chronological age was 10.3 +/- 3.5 years. Height-CDC SDS and height-NS SDS were -3.1 +/- 0.7 and -0.5 +/- 0.6, respectively. PTPN11+ patients had a better growth response than PTPN11- patients. GV SDS increased from -1.2 +/- 1.8 to 3.1 +/- 2.8 after the first year of therapy in PTPN11+ patients, and from -1.9 +/- 2.6 to -0.1 +/- 2.6 in PTPN11- patients. The gain in height-CDC SDS during the first year was higher in PTPN11+ than PTPN11- (0.6 +/- 0.4 vs. 0.1 +/- 0.2, p = 0.008). Similarly, the gain was observed in height-NS SDS (0.6 +/- 0.3 vs. 0.2 +/- 0.2, respectively, p < 0.001). Among the patients that reached adult height (n = 17), AH-CDC SDS and AH-NS SDS were -2.1 +/- 0.7 and 0.7 +/- 0.8, respectively. The total increase in height SDS was 1.3 +/- 0.7 and 1.5 +/- 0.6 for normal and NS standards, respectively. Conclusions: This study supports the advantage of rhGH therapy on adult height in PTPN11+ patients. In comparison, PTPN11- patients showed a poor response to rhGH. However, this PTPN11- group was small, preventing an adequate comparison among different genotypes and no guarantee of response to therapy in genes besides PTPN11. (C) 2019 S. Karger AG, Basel
- Phenotype-genotype analysis of 242 individuals with RASopathies: 18-year experience of a tertiary center in Brazil(2020) BERTOLA, Debora R.; CASTRO, Matheus A. A.; YAMAMOTO, Guilherme L.; HONJO, Rachel S.; CERONI, Jose Ricardo; BUSCARILLI, Michele M.; FREITAS, Amanda B.; MALAQUIAS, Alexsandra C.; PEREIRA, Alexandre C.; JORGE, Alexander A. L.; PASSOS-BUENO, Maria Rita; KIM, Chong A.We report the clinical and molecular data of a large cohort comprising 242 individuals with RASopathies, from a single Tertiary Center in Brazil, the largest study from Latin America. Noonan syndrome represented 76% of the subjects, with heterozygous variants in nine different genes, mainly PTPN11, SOS1, RAF1, LZTR1, and RIT1, detected by Sanger and next-generation sequencing. The latter was applied to 126 individuals, with a positive yield of 63% in genes of the RAS/MAPK cascade. We present evidence that there are some allelic differences in PTPN11 across distinct populations. We highlight the clinical aspects that pose more medical concerns, such as the cardiac anomalies, bleeding diathesis and proliferative lesions. The genotype-phenotype analysis between the RASopathies showed statistically significant differences in some cardinal features, such as craniofacial and cardiac anomalies, the latter also statistically significant for different genes in Noonan syndrome. We present two individuals with a Noonan syndrome phenotype, one with an atypical, structural cardiac defect, harboring variants in genes mainly associated with isolated hypertrophic cardiomyopathy and discuss the role of these variants in their phenotype.
- Growth standards of patients with Noonan and Noonan-like syndromes with mutations in the RAS/MAPK pathway(2012) MALAQUIAS, Alexsandra C.; BRASIL, Amanda S.; PEREIRA, Alexandre C.; ARNHOLD, Ivo J. P.; MENDONCA, Berenice B.; BERTOLA, Debora R.; JORGE, Alexander A. L.Noonan syndrome (NS) and Noonan-like syndromes (NLS) are autosomal dominant disorders caused by heterozygous mutations in genes of the RAS/MAPK pathway. The aim of the study was to construct specific growth charts for patients with NS and NLS. Anthropometric measurements (mean of 4.3 measurements per patient) were obtained in a mixed cross-sectional and longitudinal mode from 127 NS and 10 NLS patients with mutations identified in PTPN11 (n?=?90), SOS1 (n?=?14), RAF1 (n?=?10), KRAS (n?=?8), BRAF (n?=?11), and SHOC2 (n?=?4) genes. Height, weight, and body mass index (BMI) references were constructed using the lambda, mu, sigma (LMS) method. Patients had birth weight and length within normal ranges for gestational age although a higher preterm frequency (16%) was observed. Mean final heights were 157.4?cm [-2.4 standard deviation score (SDS)] and 148.4?cm (-2.2?SDS) for adult males and females, respectively. BMI SDS was lower when compared to Brazilian standards (BMI SDS of -0.9 and -0.5 SDS for males and females, respectively). Patients harboring mutations in RAF1 and SHOC2 gene were shorter than other genotypes, whereas patients with SOS1 and BRAF mutations had more preserved postnatal growth. In addition, patients with RAF1 and BRAF had the highest BMI whereas patients with SHOC2 and KRAS mutations had the lowest BMI. The present study established the first height, weight, and BMI reference curves for NS and NLS patients, based only on patients with a proven molecular cause. These charts can be useful for the clinical follow-up of patients with NS and NLS. (c) 2012 Wiley Periodicals, Inc.
- The Interactive Effect of GHR-Exon 3 and -202 A/C IGFBP3 Polymorphisms on rhGH Responsiveness and Treatment Outcomes in Patients with Turner Syndrome(2012) BRAZ, Adriana F.; COSTALONGA, Everlayny F.; MONTENEGRO, Luciana R.; TRARBACH, Ericka B.; ANTONINI, Sonir R. R.; MALAQUIAS, Alexsandra C.; RAMOS, Ester S.; MENDONCA, Berenice B.; ARNHOLD, Ivo J. P.; JORGE, Alexander A. L.Context: There is great interindividual variability in the response to recombinant human (rh) GH therapy in patients with Turner syndrome (TS). Ascertaining genetic factors can improve the accuracy of growth response predictions. Objective: The objective of the study was to assess the individual and combined influence of GHR-exon 3 and -202 A/C IGFBP3 polymorphisms on the short-and long-term outcomes of rhGH therapy in patients with TS. Design and Patients: GHR-exon 3 and -202 A/C IGFBP3 genotyping (rs2854744) was correlated with height data of 112 patients with TS who remained prepubertal during the first year of rhGH therapy and 65 patients who reached adult height after 5 +/- 2.5 yr of rhGH treatment. Main Outcome Measures: First-year growth velocity and adult height were measured. Results: Patients carrying at least one GHR-d3 or -202 A-IGFBP3 allele presented higher mean first-year growth velocity and achieved taller adult heights than those homozygous for GHR-fl or -202 C-IGFBP3 alleles, respectively. The combined analysis of GHR-exon 3 and -202 A/C IGFBP3 genotypes showed a clear nonadditive epistatic influence on adult height of patients with TS treated with rhGH (GHR-exon 3 alone, R-2 = 0.27; -202 A/C IGFBP3, R-2 = 0.24; the combined genotypes, R-2 = 0.37 at multiple linear regression). Together with clinical factors, these genotypes accounted for 61% of the variability in adult height of patients with TS after rhGH therapy. Conclusion: Homozygosity for the GHR-exon3 full-length allele and/or the -202C-IGFBP3 allele are associated with less favorable short-and long-term growth outcomes after rhGH treatment in patients with TS.