LUCIANA RIBEIRO MONTENEGRO
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Clínica Médica, Faculdade de Medicina
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
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article 6 Citação(ões) na Scopus Mutations in insulin-like growth factor receptor 1 gene (IGF1R) resulting in intrauterine and postnatal growth retardation(2011) LEAL, Andrea de Castro; CANTON, Ana Pinheiro Machado; MONTENEGRO, Luciana Ribeiro; COUTINHO, Debora Cabral; ARNHOLD, Ivo Jorge Prado; JORGE, Alexander Augusto de LimaApproximately 10% of children born small-for-gestational age (SGA) do not show spontaneous growth catch-up. The causes of this deficit in prenatal growth and its maintenance after birth are not completely known, in most cases. Over the past eight years, several heterozygous inactivating mutations and deletions in IGF1R gene have been reported, indicating the role of defects in the IGFs/IGF1R axis as a cause of growth deficit. It has been hypothesized that at least 2.5% of children born SGA may have IGF1R gene defects. The clinical presentation of these patients is highly variable in the severity of growth retardation and hormonal parameters. In the most evident cases, patients have microcephaly, mild cognitive impairment and high levels of IGF-1, associated with short stature of prenatal onset. This review will describe the clinical, molecular and treatment of short stature with hrGH of children with mutations in the IGF1R gene. Arq Bras Endocrinol Metab. 2011;55(8):541-9conferenceObject Apparently Sporadic Central Precocious Puberty Is Caused By Paternally Inherited Mutations in the Imprinted MKRN3 Gene(2014) ABREU, Ana Paula; MACEDO, Delanie B.; REIS, Ana Claudia Silva; MONTENEGRO, Luciana Ribeiro; DAUBER, Andrew; BENEDUZZI, Diane; CULIER, Priscilla; SILVEIRA, Leticia Gontijo; TELES, Milena Gurgel; CARROLL, Rona S.; GUERRA, Gil; GUARAGNA FILHO, Guilherme; GUCEV, Zoran Spasico; ARNHOLD, Ivo J. P.; CASTRO, Margaret; MOREIRA, Ayrton Custodio; MARTINELLI, Carlos Eduardo; HIRSCHHORN, Joel N.; MENDONASA, Berenice Bilharinho; BRITO, Vinicius N.; ANTONINI, Sonir Roberto; KAISER, Ursula B.; LATRONICO, Ana Claudia- Allelic Variants in Established Hypopituitarism Genes Expand Our Knowledge of the Phenotypic Spectrum(2021) NAKAGUMA, Marilena; FERREIRA, Nathalia Garcia Bianchi Pereira; BENEDETTI, Anna Flavia Figueredo; MADI, Mariana Cotarelli; SILVA, Juliana Moreira; LI, Jun Z.; MA, Qianyi; OZEL, Ayse Bilge; FANG, Qing; NARCIZO, Amanda de Moraes; CARDOSO, Lais Cavalca; MONTENEGRO, Luciana Ribeiro; FUNARI, Mariana Ferreira de Assis; NISHI, Mirian Yumie; ARNHOLD, Ivo Jorge Prado; JORGE, Alexander Augusto de Lima; MENDONCA, Berenice Bilharinho de; CAMPER, Sally Ann; CARVALHO, Luciani R.We report four allelic variants (three novel) in three genes previously established as causal for hypopituitarism or related disorders. A novel homozygous variant in the growth hormone gene, GH1 c.171delT (p.Phe 57Leufs*43), was found in a male patient with severe isolated growth hormone deficiency (IGHD) born to consanguineous parents. A hemizygous SOX3 allelic variant (p.Met304Ile) was found in a male patient with IGHD and hypoplastic anterior pituitary. YASARA, a tool to evaluate protein stability, suggests that p.Met304Ile destabilizes the SOX3 protein (Delta Delta G = 2.49 kcal/mol). A rare, heterozygous missense variant in the TALE homeobox protein gene, TGIF1 (c.268C>T:p.Arg90Cys) was found in a patient with combined pituitary hormone deficiency (CPHD), diabetes insipidus, and syndromic features of holoprosencephaly (HPE). This variant was previously reported in a patient with severe holoprosencephaly and shown to affect TGIF1 function. A novel heterozygous TGIF1 variant (c.82T>C:p.Ser28Pro) was identified in a patient with CPHD, pituitary aplasia and ectopic posterior lobe. Both TGIF1 variants have an autosomal dominant pattern of inheritance with incomplete penetrance. In conclusion, we have found allelic variants in three genes in hypopituitarism patients. We discuss these variants and associated patient phenotypes in relation to previously reported variants in these genes, expanding our knowledge of the phenotypic spectrum in patient populations.
- FGFR1 and PROKR2 rare variants found in patients with combined pituitary hormone deficiencies(2015) CORREA, Fernanda A.; TRARBACH, Ericka B.; TUSSET, Cintia; LATRONICO, Ana Claudia; MONTENEGRO, Luciana R.; CARVALHO, Luciani R.; FRANCA, Marcela M.; OTTO, Aline P.; COSTALONGA, Everlayny F.; BRITO, Vinicius N.; ABREU, Ana Paula; NISHI, Mirian Y.; JORGE, Alexander A. L.; ARNHOLD, Ivo J. P.; SIDIS, Yisrael; PITTELOUD, Nelly; MENDONCA, Berenice B.The genetic aetiology of congenital hypopituitarism (CH) is not entirely elucidated. FGFR1 and PROKR2 loss-of-function mutations are classically involved in hypogonadotrophic hypogonadism (HH), however, due to the clinical and genetic overlap of HH and CH; these genes may also be involved in the pathogenesis of CH. Using a candidate gene approach, we screened 156 Brazilian patients with combined pituitary hormone deficiencies (CPHD) for loss-of-function mutations in FGFR1 and PROKR2. We identified three FGFR1 variants (p.Arg448Trp, p.Ser107Leu and p.Pro772Ser) in four unrelated patients (two males) and two PROKR2 variants (p. Arg85Cys and p. Arg248Glu) in two unrelated female patients. Five of the six patients harbouring the variants had a first-degree relative that was an unaffected carrier of it. Results of functional studies indicated that the new FGFR1 variant p.Arg448Trp is a loss-of-function variant, while p.Ser107Leu and p.Pro772Ser present signalling activity similar to the wild-type form. Regarding PROKR2 variants, results from previous functional studies indicated that p.Arg85Cys moderately compromises receptor signalling through both MAPK and Ca2+ pathways while p.Arg248Glu decreases calcium mobilization but has normal MAPK activity. The presence of loss-of-function variants of FGFR1 and PROKR2 in our patients with CPHD is indicative of an adjuvant and/or modifier effect of these rare variants on the phenotype. The presence of the same variants in unaffected relatives implies that they cannot solely cause the phenotype. Other associated genetic and/or environmental modifiers may play a role in the aetiology of this condition.
- Post-receptor IGF1 insensitivity restricted to the MAPK pathway in a Silver-Russell syndrome patient with hypomethylation at the imprinting control region on chromosome 11(2012) MONTENEGRO, Luciana R.; LEAL, Andrea C.; COUTINHO, Debora C.; VALASSI, Helena P. L.; NISHI, Mirian Y.; PARNHOLD, Ivo J.; MENDONCA, Berenice B.; JORGE, Alexander A. L.Background: Hypomethylation of the paternal imprinting center region 1 (ICR1) is the most frequent molecular cause of Silver-Russell syndrome (SRS). Clinical evidence suggests that patients with this epimutation have mild IGF1 insensitivity. Objective: To assess in vitro IGF1 action in fibroblast culture from a patient with SRS and IGF1 insensitivity. Methods: Fibroblast cultures from one patient with SRS due to ICR1 demethylation and controls were established. The SRS patient has severe growth failure, elevated IGF1 level, and poor growth rate during human recombinant GH treatment. IGF1 action was assessed by cell proliferation, AKT, and p42/44-MAPK phosphorylation. Gene expression was determined by real-time PCR. Results: Despite normal IGF1R sequence and expression, fibroblast proliferation induced by IGF1 was 50% lower in SRS fibroblasts in comparison with controls. IGF1 and insulin promoted a p42/44-MAPK activation in SRS fibroblasts 40 and 36%, respectively, lower than that in control fibroblasts. On the other hand, p42/44-MAPK activation induced by EGF stimulation was only slightly reduced (75% in SRS fibroblasts in comparison with control), suggesting a general impairment in MAPK pathway with a greater impairment of the stimulation induced by insulin and IGF1 than by EGF. A PCR array analysis disclosed a defect in MAPK pathway characterized by an increase in DUSP4 and MEF2C gene expressions in patient fibroblasts. Conclusion: A post-receptor IGF1 insensitivity was characterized in one patient with SRS and ICR1 hypomethylation. Although based on one unique severely affected patient, these results raise an intriguing mechanism to explain the postnatal growth impairment observed in SRS patients that needs confirmation in larger cohorts.
- Analysis of the insulin-like growth factor 1 receptor gene in children born small for gestational age: in vitro characterization of a novel mutation (p.Arg511Trp)(2013) LEAL, Andrea C.; MONTENEGRO, Luciana R.; SAITO, Renata F.; RIBEIRO, Tamaya C.; COUTINHO, Debora C.; MENDONCA, Berenice B.; ARNHOLD, Ivo J. P.; JORGE, Alexander A. L.Background Insulin-like growth factor 1 insensitivity caused by IGF1R mutations has been previously identified as one of the causes of growth impairment in children born small for gestational age (SGA). Objective To analyse the IGF1R in children born SGA. Subjects From an initial cohort of 54 sequential children born SGA, without catch-up growth, 25 children were selected for this IGF1R study due to the presence of serum IGF-1 values above the mean for their age and sex. Methods The proximal IGF1R promoter region, the entire coding region and the exonintron boundaries were directly sequenced, and multiplex ligation-dependent probe amplification analysis was performed. Fibroblast cultures were developed from one patient with a mutation for the in vitro characterization of IGF-1 insensitivity. Results The copy number variation analysis did not identify deletions involving the IGF1R gene. We identified two children carrying heterozygous nucleotide substitutions in IGF1R: c.16G>A/p.Gly6Arg and c.1531C>T/p.Arg511Trp. The first variant (p.Gly6Arg) was identified in control subjects (0 center dot 3%) and in a relative with normal growth; thus, it was considered to be a rare benign allelic variation. The second variant (p.Arg511Trp) was not found in 306 alleles from control subjects, and it segregated with the growth impairment phenotype in the patient's family. Fibroblasts obtained from this patient had a significantly reduced proliferative response and AKT phosphorylation after IGF-1 stimulation compared with control fibroblasts. Conclusion The identification of an inactivating IGF1R mutation in the present cohort should encourage further studies of larger series to establish the precise frequency of this molecular defect in children with growth impairment of a prenatal onset.
- 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.
- A homozygous point mutation in the GH1 promoter (c.-223C > T) leads to reduced GH1 expression in siblings with isolated GH deficiency (IGHD)(2016) MADEIRA, Joao L. O.; JORGE, Alexander A. L.; MARTIN, Regina M.; MONTENEGRO, Luciana R.; FRANCA, Marcela M.; COSTALONGA, Everlayny F.; CORREA, Fernanda A.; OTTO, Aline P.; ARNHOLD, Ivo J. P.; FREITAS, Helayne S.; MACHADO, Ubiratan F.; MENDONCA, Berenice B.; CARVALHO, Luciani R.Context: Mutations in the GH1 promoter are a rare cause of isolated growth hormone deficiency (IGHD). Objective: To identify the molecular aetiology of a family with IGHD. Design: DNA sequencing, electromobility shift (EMSA) and luciferase reporter assays. Setting: University Hospital. Patients: Three siblings (2M) born to consanguineous parents presented with IGHD with normal pituitary on MRI. Methods: The GH1 proximal promoter, locus control region, five exons and four introns as well as GHRHR gene were sequenced in genomic DNA by Sanger method. DNA- protein interaction was evaluated by EMSA in nuclear extracts of GH3 pituitary cells. Dual-luciferase reporter assays were performed in cells transiently transfected with plasmids containing four different combinations of GH1 allelic variants (AV). Results: The patients harboured two homozygous variants (c.-185T>C and c.-223C>T) in the GH1 promoter within a highly conserved region and predicted binding sites for POU1F1/SP1 and SP1 respectively. The parents and brother were carriers and these variants were absent in 100 controls. EMSA demonstrated absent binding of GH3 nuclear extract to the c.-223C>T variant and normal binding of both POU1F1 protein and GH3 nuclear extract to the c.-185T>C variant. In contrast to GH1 promoter with AV only at c.-185, the GH1 promoter containing the AV only at c.-223 and at both positions drove significantly less expression of luciferase compared with the promoter containing either positions wild type in luciferase reporter assays. Conclusion: To our knowledge, c.-223C>T is the first homozygous point mutation in the GH1 promoter that leads to short stature due to IGHD.
- Central Precocious Puberty That Appears to Be Sporadic Caused by Paternally Inherited Mutations in the Imprinted Gene Makorin Ring Finger 3(2014) MACEDO, Delanie B.; ABREU, Ana Paula; REIS, Ana Claudia S.; MONTENEGRO, Luciana R.; DAUBER, Andrew; BENEDUZZI, Daiane; CUKIER, Priscilla; SILVEIRA, Leticia F. G.; TELES, Milena G.; CARROLL, Rona S.; GUERRA JUNIOR, Gil; GUARAGNA FILHO, Guilherme; GUCEV, Zoran; ARNHOLD, Ivo J. P.; CASTRO, Margaret de; MOREIRA, Ayrton C.; MARTINELLI JR., Carlos Eduardo; HIRSCHHORN, Joel N.; MENDONCA, Berenice B.; BRITO, Vinicius N.; ANTONINI, Sonir R.; KAISER, Ursula B.; LATRONICO, Ana ClaudiaContext: Loss-of-function mutations in makorin ring finger 3 (MKRN3), an imprinted gene located on the long arm of chromosome 15, have been recognized recently as a cause of familial central precocious puberty (CPP) in humans. MKRN3 has a potential inhibitory effect on GnRH secretion. Objectives: The objective of the study was to investigate potential MKRN3 sequence variations as well as copy number and methylation abnormalities of the 15q11 locus in patients with apparently sporadic CPP. Setting and Participants: We studied 215 unrelated children (207 girls and eight boys) from three university medical centers with a diagnosis of CPP. All but two of these patients (213 cases) reported no family history of premature sexual development. First-degree relatives of patients with identified MKRN3 variants were included for genetic analysis. Main Outcome Measures: All 215 CPP patients were screened for MKRN3 mutations by automatic sequencing. Multiplex ligation-dependent probe amplification was performed in a partially overlapping cohort of 52 patients. Results: We identified five novel heterozygous mutations in MKRN3 in eight unrelated girls with CPP. Four were frame shift mutations predicted to encode truncated proteins and one was a missense mutation, which was suggested to be deleterious by in silico analysis. All patients with MKRN3mutations had classical features of CPP with a median age of onset at 6 years. Copy number and methylation abnormalities at the 15q11 locus were not detected in the patients tested for these abnormalities. Segregation analysis was possible in five of the eight girls with MKRN3 mutations; in all cases, the mutation was inherited on the paternal allele. Conclusions: We have identified novel inherited MKRN3 defects in children with apparently sporadic CPP, supporting a fundamental role of this peptide in the suppression of the reproductive axis.
conferenceObject A Homozygous Point Mutation in the GH1 Promoter (-161T > C) Leads to Reduced GH Expression in Siblings with Isolated GH Deficiency (IGHD)(2015) CARVALHO, L.; MADEIRA, J.; MARTIN, R.; MONTENEGRO, L.; FRANCA, M.; COSTALONGA, E.; CORREA, F.; OTTO, A.; ARNHOLD, I; FREITAS, H.; MACHADO, U.; MENDONCA, B.; JORGE, A.