ALEXANDER AUGUSTO DE LIMA JORGE
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Clínica Médica, Faculdade de Medicina - Docente
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
LIM/25 - Laboratório de Endocrinologia Celular e Molecular, Hospital das Clínicas, Faculdade de Medicina - Líder
LIM/42 - Laboratório de Hormônios e Genética Molecular, Hospital das Clínicas, Faculdade de Medicina
LIM/25 - Laboratório de Endocrinologia Celular e Molecular, Hospital das Clínicas, Faculdade de Medicina - Líder
11 resultados
Resultados de Busca
Agora exibindo 1 - 10 de 11
- STAT5B mutations in heterozygous state have negative impact on height: another clue in human stature heritability(2015) SCALCO, Renata C.; HWA, Vivian; DOMENE, Horacio M.; JASPER, Hector G.; BELGOROSKY, Alicia; MARINO, Roxana; PEREIRA, Alberto M.; TONELLI, Carlos A.; WIT, Jan M.; ROSENFELD, Ron G.; JORGE, Alexander A. L.Context and objective: GH insensitivity with immune dysfunction caused by STAT5B mutations is an autosomal recessive condition. Heterozygous mutations in other genes involved in growth regulation were previously associated with a mild height reduction. Our objective was to assess for the first time the phenotype of heterozygous STAT5B mutations. Methods: We genotyped and performed clinical and laboratory evaluations in 52 relatives of two previously described Brazilian brothers with homozygous STAT5B c.424_427del mutation (21 heterozygous). Additionally, we obtained height data and genotype from 1104 adult control individuals from the same region in Brazil and identified five additional families harboring the same mutation (18 individuals, 11 heterozygous). Furthermore, we gathered the available height data from first-degree relatives of patients with homozygous STAT5B mutations (17 individuals from seven families). Data from heterozygous individuals and non-carriers were compared. Results: Individuals carrying heterozygous STAT5B c.424_427del mutation were 0.6 SDS shorter than their non-carrier relatives (P=0.009). Heterozygous subjects also had significantly lower SDS for serum concentrations of IGF1 (P=0.028) and IGFBP3 (P=0.02) than their non-carrier relatives. The 17 heterozygous first-degree relatives of patients carrying homozygous STAT5B mutations had an average height SDS of -1.4 +/- 0.8 when compared with population-matched controls (P<0.001). Conclusions: STAT5B mutations in the heterozygous state have a significant negative impact on height (similar to 3.9 cm). This effect is milder than the effect seen in the homozygous state, with height usually within the normal range. Our results support the hypothesis that heterozygosity of rare pathogenic variants contributes to normal height heritability.
- Germline mutation landscape of multiple endocrine neoplasia type 1 using full gene next-generation sequencing(2018) CARVALHO, Rafael A.; URTREMARI, Betsaida; JORGE, Alexander A. L.; SANTANA, Lucas S.; QUEDAS, Elisangela P. S.; SEKIYA, Tomoko; LONGUINI, Viviane C.; MONTENEGRO, Fabio L. M.; LERARIO, Antonio M.; TOLEDO, Sergio P. A.; MARX, Stephen J.; TOLEDO, Rodrigo A.; JR, Delmar M. LourencoBackground: Loss-of-function germline MEN1 gene mutations account for 75-95% of patients with multiple endocrine neoplasia type 1 (MEN1). It has been postulated that mutations in non-coding regions of MEN1 might occur in some of the remaining patients; however, this hypothesis has not yet been fully investigated. Objective: To sequence for the entire MEN1 including promoter, exons and introns in a large MEN1 cohort and determine the mutation profile. Methods and patients: A target next-generation sequencing (tNGS) assay comprising 7.2 kb of the full MEN1 was developed to investigate germline mutations in 76 unrelated MEN1 probands (49 familial, 27 sporadic). tNGS results were validated by Sanger sequencing (SS), and multiplex ligation-dependent probe amplification (MLPA) assay was applied when no mutations were identifiable by both tNGS and SS. Results: Germline MEN1 variants were verified in coding region and splicing sites of 57/76 patients (74%) by both tNGS and SS (100% reproducibility). Thirty-eight different pathogenic or likely pathogenic variants were identified, including 13 new and six recurrent variants. Three large deletions were detected by MLPA only. No mutation was detected in 16 patients. In untranslated, regulatory or in deep intronic MEN1 regions of the 76 MEN1 cases, no point or short indel pathogenic variants were found in untranslated, although 33 benign/likely benign and three new VUS variants were detected. Conclusions: Our study documents that point or short indel mutations in non-coding regions of MEN1 are very rare events. Also, tNGS proved to be a highly effective technology for routine genetic MEN1 testing.
- The phenotypic spectrum associated with OTX2 mutations in humans(2021) GREGORY, Louise C.; GERGICS, Peter; NAKAGUMA, Marilena; BANDO, Hironori; PATTI, Giuseppa; MCCABE, Mark J.; FANG, Qing; MA, Qianyi; OZEL, Ayse Bilge; LI, Jun Z.; POINA, Michele Moreira; JORGE, Alexander A. L.; BENEDETTI, Anna F. Figueredo; LERARIO, Antonio M.; ARNHOLD, Ivo J. P.; MENDONCA, Berenice B.; MAGHNIE, Mohamad; CAMPER, Sally A.; CARVALHO, Luciani R. S.; DATTANI, Mehul T.Objective: The transcription factor OTX2 is implicated in ocular, craniofacial, and pituitary development.& nbsp; Design: We aimed to establish the contribution of OTX2 mutations in congenital hypopituitarism patients with/without eye abnormalities, study functional consequences, and establish OTX2 expression in the human brain, with a view to investigate the mechanism of action.& nbsp; Methods: We screened patients from the UK (n = 103), international centres (n = 24), and Brazil (n = 282); 145 were within the septo-optic dysplasia spectrum, and 264 had no eye phenotype. Transactivation ability of OTX2 variants was analysed in murine hypothalamic GT1-7 neurons. In situ hybridization was performed on human embryonic brain sections. Genetically engineered mice were generated with a series of C-terminal OTX2 variants.& nbsp; Results: Two chromosomal deletions and six haploinsufficient mutations were identified in individuals with eye abnormalities; an affected relative of one patient harboured the same mutation without an ocular phenotype. OTX2 truncations led to significant transactivation reduction. A missense variant was identified in another patient without eye abnormalities; however, studies revealed it was most likely not causative. In the mouse, truncations proximal to aa219 caused anophthalmia, while distal truncations and the missense variant were tolerated. During human embryogenesis, OTX2 was expressed in the posterior pituitary, retina, ear, thalamus, choroid plexus, and partially in the hypothalamus, but not in the anterior pituitary.& nbsp; Conclusions: OTX2 mutations are rarely associated with hypopituitarism in isolation without eye abnormalities, and may be variably penetrant, even within the same pedigree. Our data suggest that the endocrine phenotypes in patients with OTX2 mutations are of hypothalamic origin.
- 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.
- Novel inactivating mutations in the GH secretagogue receptor gene in patients with constitutional delay of growth and puberty(2011) PUGLIESE-PIRES, Patricia N.; FORTIN, Jean-Philippe; ARTHUR, Thais; LATRONICO, Ana Claudia; MENDONCA, Berenice B.; VILLARES, Sandra Mara F.; PARNHOLD, Ivo J.; KOPIN, Alan S.; JORGE, Alexander A. L.Background: A limited number of mutations in the GH secretagogue receptor gene (GHSR) have been described in patients with short stature. Objective: To analyze GHSR in idiopathic short stature (ISS) children including a subgroup of constitutional delay of growth and puberty (CDGP) patients. Subjects and methods: The GHSR coding region was directly sequenced in 96 independent patients with ISS, 31 of them with CDGP, in 150 adults, and in 197 children with normal stature. The pharmacological consequences of GHSR non-synonymous variations were established using in vitro cell-based assays. Results: Five different heterozygous point variations in GHSR were identified (c.-6 G>C, c.251G>T (p.Ser84Ile), c.505G>A (p.Ala169Thr), c.545 T>C (p.Val182Ala), and c.1072G>A (p.Ala358Thr)), all in patients with CDGP. Neither these allelic variants nor any other mutations were found in 694 alleles from controls. Functional studies revealed that two of these variations (p.Ser84Ile and p. Val182Ala) result in a decrease in basal activity that was in part explained by a reduction in cell surface expression. The p.Ser84Ile mutation was also associated with a defect in ghrelin potency. These mutations were identified in two female patients with CDGP (at the age of 13 years, their height SDS were -2.4 and -2.3). Both patients had normal progression of puberty and reached normal adult height (height SDS of -0.7 and -1.4) without treatment. Conclusion: This is the first report of GHSR mutations in patients with CDGP. Our data raise the intriguing possibility that abnormalities in ghrelin receptor function may influence the phenotype of individuals with CDGP.
- New genetic findings in a large cohort of congenital hypogonadotropic hypogonadism(2019) AMATO, Lorena Guimaraes Lima; MONTENEGRO, Luciana Ribeiro; LERARIO, Antonio Marcondes; JORGE, Alexander Augusto Lima; GUERRA JUNIOR, Gil; SCHNOLL, Caroline; RENCK, Alessandra Covallero; TRARBACH, Ericka Barbosa; COSTA, Elaine Maria Frade; MENDONCA, Berenice Bilharinho; LATRONICO, Ana Claudia; SILVEIRA, Leticia Ferreira GontijoContext: Congenital hypogonadotropic hypogonadism (CHH) is a rare condition caused by GnRH deficiency. Several genes have been associated with the pathogenesis of CHH, but most cases still remain without a molecular diagnosis. The advent of next-generation sequencing (NGS) has allowed the simultaneous genotyping of several regions, faster, making possible the extension of the genetic knowledge of CHH. Objective: Genetic characterization of a large cohort of Brazilian CHH patients. Design and patients: A cohort of 130 unrelated patients (91 males, 39 females) with CHH (75 normosmic CHH, 55 Kallmann syndrome) was studied using a panel containing 36 CHH-associated genes. Results: Potential pathogenic or probably pathogenic variants were identified in 43 (33%) CHH patients. The genes ANOS1, FGFR1 and GNRHR were the most frequently affected. A novel homozygous splice site mutation was identified in the GNRH1 gene and a deletion of the entire coding sequence was identified in SOX10. Deleterious variants in the IGSF10 gene were identified in two patients with reversible normosmic CHH. Notably, 6.9% of the patients had rare variants in more than one gene. Rare variants were also identified in SPRY4, IL17RD, FGF17, IGSF1 and FLRT3 genes. Conclusions: This is a large study of the molecular genetics of CHH providing new genetic findings for this complex and heterogeneous genetic condition. NGS has been shown to be a fast, reliable and effective tool in the molecular diagnosis of congenital CHH and being able to targeting clinical genetic testing in the future.
- Diagnostic and therapeutic approach of tall stature(2017) ALBUQUERQUE, Edoarda V. A.; SCALCO, Renata C.; JORGE, Alexander A. L.Tall stature is defined as a height of more than 2 standard deviations (s.d.) above average for same sex and age. Tall individuals are usually referred to endocrinologists so that hormonal disorders leading to abnormal growth are excluded. However, the majority of these patients have familial tall stature or constitutional advance of growth (generally associated with obesity), both of which are diagnoses of exclusion. It is necessary to have familiarity with a large number of rarer overgrowth syndromes, especially because some of them may have severe complications such as aortic aneurysm, thromboembolism and tumor predisposition and demand-specific follow-up approaches. Additionally, endocrine disorders associated with tall stature have specific treatments and for this reason their recognition is mandatory. With this review, we intend to provide an up-to-date summary of the genetic conditions associated with overgrowth to emphasize a practical diagnostic approach of patients with tall stature and to discuss the limitations of current growth interruption treatment options.
- Genetic investigation of patients with tall stature(2020) ALBUQUERQUE, Edoarda Vasco de Albuquerque; FUNARI, Mariana Ferreira de Assis; QUEDAS, Elisangela Pereira de Souza; KAWAHIRA, Rachel Sayuri Honjo; JALLAD, Raquel Soares; HOMMA, Thais Kataoka; MARTIN, Regina Matsunaga; BRITO, Vinicius Nahime; MALAQUIAS, Alexsandra Christianne; LERARIO, Antonio Marcondes; ROSENBERG, Carla; KREPISCHI, Ana Cristina Victorino; KIM, Chong Ae; ARNHOLD, Ivo Jorge Prado; JORGE, Alexander Augusto de LimaContext: Patients with tall stature often remain undiagnosed after clinical investigation and few studies have genetically assessed this group, most of them without a systematic approach. Objective: To assess prospectively a group of individuals with tall stature, with and without syndromic features, and to establish a molecular diagnosis for their growth disorder. Design: Screening by karyotype (n = 42), chromosome microarray analyses (CMA) (n = 16), MS-MLPA (n = 2) targeted panel (n = 12) and whole-exome sequencing (n = 31). Patients and methods: We selected 42 patients with tall stature after exclusion of pathologies in GH/IGF1 axis and divided them into syndromic (n = 30) and non-syndromic (n = 12) subgroups. Main outcome measures: Frequencies of pathogenic findings. Results: We identified two patients with chromosomal abnormalities including SHOX trisomy by karyotype, one 9q22.3 microdeletion syndrome by CMA, two cases of Beckwith-Wiedemann syndrome by targeted MS-MLPA analysis and nine cases with heterozygous pathogenic or likely pathogenic genetic variants by multigene analysis techniques (FBN1 = 3, NSD1 = 2, NFIX = 1, SUZ12 = 1, CHD8 = 1, MC4R = 1). Three of 20 patients analyzed by WES had their diagnosis established. Only one non-syndromic patient had a definitive diagnosis. The sequential genetic assessment diagnosed 14 out of 42 (33.3%) tall patients. Conclusion: A systematic molecular approach of patients with tall stature was able to identify the etiology in 13 out of 30 (43.3%) syndromic and 1 out of 12 (8.3%) non-syndromic patients, contributing to the genetic counseling and avoiding unfavorable outcomes in the syndromic subgroup.
- 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.
- Identification of a second genetic alteration in patients with SHOX deficiency individuals: a potential explanation for phenotype variability(2023) DANTAS, Naiara C. B.; FUNARI, Mariana F. A.; LERARIO, Antonio M.; ANDRADE, Nathalia L. M.; REZENDE, Raissa C.; CELLIN, Laurana P.; ALVES, Cresio; CRISOSTOMO, Lindiane G.; ARNHOLD, Ivo J. P.; MENDONCA, Berenice; SCALCO, Renata C.; JORGE, Alexander A. L.Objective Our study aimed to assess the impact of genetic modifiers on the significant variation in phenotype that is observed in individuals with SHOX deficiency, which is the most prevalent monogenic cause of short stature.Design and methods We performed a genetic analysis in 98 individuals from 48 families with SHOX deficiency with a target panel designed to capture the entire SHOX genomic region and 114 other genes that modulate growth and/or SHOX action. We prioritized rare potentially deleterious variants.Results We did not identify potential deleterious variants in the promoter or intronic regions of the SHOX genomic locus. In contrast, we found eight heterozygous variants in 11 individuals from nine families in genes with a potential role as genetic modifiers. In addition to a previously described likely pathogenic (LP) variant in CYP26C1 observed in two families, we identified LP variants in PTHLH and ACAN, and variants of uncertain significance in NPR2, RUNX2, and TP53 in more affected individuals from families with SHOX deficiency. Families with a SHOX alteration restricted to the regulatory region had a higher prevalence of a second likely pathogenic variant (27%) than families with an alteration compromising the SHOX coding region (2.9%, P = .04).Conclusion In conclusion, variants in genes related to the growth plate have a potential role as genetic modifiers of the phenotype in individuals with SHOX deficiency. In individuals with SHOX alterations restricted to the regulatory region, a second alteration could be critical to determine the penetrance and expression of the phenotype.