Skeletal abnormalities of tricho-rhino-phalangeal syndrome type I

Molecular Genetic Analysis and Growth Hormone Treatment in a Three-Generation Chinese Family with Tricho-Rhino-Phalangeal Syndrome I

INTRODUCTION

Tricho-rhino-phalangeal syndrome (TRPS) is a rare genetic disorder characterized by craniofacial and skeletal abnormalities, which is caused by variants in the TRPS1 gene.

METHODS

Clinical information and follow-up data were collected. Whole-exome sequencing (WES) was performed for variants and validated by Sanger sequencing. Bioinformatic analysis was performed to predict the pathogenicity of the identified variant. Moreover, wild-type and mutated TRPS1 vectors were constructed and transfected into human embryonic kidney (HEK) 293T cells. Immunofluorescence experiments were performed to assess the localization and expression of the mutated protein. Western blot analysis and RT-qPCR were used to detect the expression of downstream genes.

RESULTS

The affected family members had typical craniofacial phenotype including sparse lateral eyebrows, pear-shaped nasal tip, and large prominent ears, plus skeletal abnormalities including short stature and brachydactyly. WES and Sanger sequencing identified the TRPS1 c.880_882delAAG variant in affected family members. In vitro functional studies showed that the TRPS1 variant did not affect the cellular localization and the expression of TRPS1, but the transcriptional repression effect of the TRPS1 on the RUNX2 and STAT3 was disturbed. The proband and his brother have been treated with growth hormone (GH) for 2 years until now, and we have observed the improvement of the linear growth in both.

CONCLUSIONS

The variant of c.880_882delAAG in TRPS1 was responsible for the pathogenesis of the Chinese family with TRPS I. The treatment of GH could be beneficial for the height outcome in TRPS I patients, and earlier initiation and longer duration of the therapy in prepubertal or early pubertal stage could be associated with better height outcomes.

Recombinant Human Growth Hormone Therapy for Childhood Trichorhinophalangeal Syndrome Type I: A Case Report

Trichorhinophalangeal syndrome type I (TRPS I; MIM 190350) is a rare autosomal dominant disorder of congenital malformations due to variants of the gene TRPS1. We reported on an 11-year-old Chinese boy with TRPS I. He had typical clinical findings, including sparse hair, a bulbous nose, a long philtrum, a thin upper lip, and skeletal abnormalities including cone-shaped epiphyses, shortening of the phalanges, and short stature. Trio whole exome sequencing identified a likely pathogenic heterozygous variant c.1957C > T (p.Q653*) in exon 4 of TRPS1, which has not been previously reported. He had been treated with rhGH therapy at a dose of 0.34 mg/(kg/week) at age 11, and a follow-up was conducted for one year. The rhGH therapy led to an increase in growth with a mean growth velocity of 1.12 cm/month (+1.1 SDS/year), and insulin-like growth factor 1 (IGF-1) concentration increased within normal range in our case. Moreover, we summarize 12 cases with TRPS I, including TRPS1 gene variants, growth hormone (GH) axis evaluation, IGF-1 concentration, and treatment in each analyzed case. Eight cases with TRPS I show a good response to rhGH therapy, and five of them have elevated IGF-1. Classic GH deficiency is not common among patients with TRPS I. The presence or absence of GH deficiency is not an absolute criterion for determining whether rhGH therapy should be used in TRPS I. It proves that rhGH therapy improves height outcomes before puberty in TRPS I in the short term. Effects on final adult height will need a longer follow-up and more adult-height data. The rise in IGF-1 could correlate with an increase in short-term height. Measuring IGF-1 levels is recommended as part of the assessment during the follow-up of patients with TRPS I.

A 15-Year-Old Girl with Trichorhinophalangeal Syndrome Type 1 with Non-ossifying Fibroma in Femur: A Case Report

Introduction: Trichorhinophalangeal syndrome (TRPS) is a sporadic autosomal dominant disorder with approximately 200 reported cases worldwide. We aimed to report a 15-year-old girl with TRPS type 1 (TRPS1) and the second reported case with a rare non-ossifying fibroma (NOF) in the distal part of her left femur. Case Presentation: We introduce a 15-year-old girl who presented to the outpatient rheumatology clinic at 17 Shahrivar Children's Hospital, Rasht, Iran, with the chief complaint of osteoarticular pain and bone deformities. She had sparse hair, a recession of the fronto-temporal hairline, and unusually thick eyebrows at the medial and abnormal sparseness of the lateral margins. Physical examination of the limbs revealed short fingers and toes with proximal interphalangeal (PIP) ulnar deviation of the second and third fingers in both hands. Shortness of the fourth fingers, especially in the right hand, and the swelling of the PIP joints of both hands were prominent. Genetic analysis showed deletion mutation in the TRPS1 gene in chromosome 8q24 compatible with TRPS1. Conclusions: Several symptoms and signs, including distinctive craniofacial features and ectodermal and skeletal abnormalities, are used for proper TRPS diagnosis. A correct and on-time diagnosis is essential to perform supportive care for the patient to prevent morbidities. Bone lesions, such as NOF1, can also be presented in TRPS1 patients and may be correlated with TRPS1 mutation. Further investigations are required on the association of the TRPS gene with NOF bone lesions.

An early diagnosis of trichorhinophalangeal syndrome type 1: a case report and a review of literature

Background

Trichorhinophalangeal syndrome (TRPS) is a rare autosomal dominant disorder caused by defects involving the TRPS1 gene. It exhibits distinctive craniofacial, ectodermal and skeletal abnormalities, such as sparse hair, bulbous nasal tip and short deformed fingers, with extremely variable expressivity.

Case presentation

We report the case of a 17 months old girl, who presented growth retardation and dysmorphic features. Postnatal growth was always below − 2 Standard Deviation for both weight and length and physical examination revealed relative macrocephaly, sparse hair, bulbous nasal tip, thin upper lip, protruding ears, prominent forehead, small jaw, and short hands and feet. Patient’s mother shared the same facial features, and presented sparse hair and small hands. The maternal grandfather and two uncles presented short stature, bulbous nasal tip, thin hair, and premature alopecia. Molecular analysis of TRPS1 gene showed a heterozygous c.2086C > T;(p.Arg696Ter) mutation both in the patient and her mother, confirming the diagnosis of TRPS, type I.

Conclusions

Clinical phenotype of TRPS can be subtle and the syndrome often remains undiagnosed. A comprehensive clinical examination and an exhaustive family history are crucial to reach the correct diagnosis, which is essential to perform adequate follow-up and timely therapeutic procedures.

Identifying potentially common genes between dyslipidemia and osteoporosis using novel analytical approaches

Dyslipidemia (DL) is closely related to osteoporosis (OP), while the exact common genetic mechanisms are still largely unknown. We proposed to use novel genetic analysis methods with pleiotropic information to identify potentially novel and/or common genes for the potential shared pathogenesis associated with OP and/or DL. We assessed the pleiotropy between plasma lipid (PL) and femoral neck bone mineral density (FNK BMD). We jointly applied the conditional false discovery rate (cFDR) method and the genetic analysis incorporating pleiotropy and annotation (GPA) method to the summary statistics provided by genome-wide association studies (GWASs) of FNK BMD (n = 49,988) and PL (n = 188,577) to identify potentially novel and/or common genes for BMD/PL. We found strong pleiotropic enrichment between PL and FNK BMD. Two hundred and forty-five PL SNPs were identified as potentially novel SNPs by cFDR and GPA. The corresponding genes were enriched in gene ontology (GO) terms "phospholipid homeostasis" and "chylomicron remnant clearance". Three SNPs (rs2178950, rs9939318, and rs9368716) might be the pleiotropic ones and the corresponding genes NLRC5 (rs2178950) and TRPS1 (rs9939318) were involved in NF-κB signaling pathway and Wnt signaling pathway as well as inflammation and innate immune processes. Our study validated the pleiotropy between PL and FNK BMD, and corroborated the reliability and high-efficiency of cFDR and GPA methods in further analyses of existing GWASs with summary statistics. We identified potentially common and/or novel genes for PL and/or FNK BMD, which may provide new insight and direction for further research.

Multiple long bone cysts revealed by MRI in trichorhinophalangeal syndrome type II predisposing to pathological fractures

Trichorhinophalangeal syndrome type II is a rare genetic disorder with the few published case reports mainly reporting the radiographic skeletal manifestations. There are no published imaging reports of long bone cysts involving multiple bones in this condition. We report a unique case of bone cysts involving multiple long bones detected with MRI in a patient with trichorhinophalangeal syndrome type II complicated by a subsequent pathological fracture. It is possible that the bone cysts are a previously undescribed feature of this syndrome; however, the evidence is insufficient to establish a definite association. Chromosomal abnormality identified in this patient is consistent with trichorhinophalangeal syndrome type II with no unusual features. Although the nature of these bone cysts is unclear, they are one of the causes of the known increased fracture risk observed in this syndrome.

Overexpression of Trps1 contributes to tumor angiogenesis and poor prognosis of human osteosarcoma

Background

Trichorhinophalangeal syndrome 1 (Trps1) gene is a member of GATA transcription factor family and has an important function in tumorigenesis and progression. However, there are rare studies on its roles in carcinogenesis and prognostic significance in human osteosarcoma.

Methods

The expression of Trps1 was detected by immunohistochemistry, and MVD was evaluated to determine the amounts of microvessels by counting CD31-positive endothelial cells.

Results

Of the 74 cases that underwent study, Trps1-positive cases were 24. And it was associated with MVD significantly (P = 0.008). The data also exhibited more cases of remote metastasis (P = 0.013) and higher Enneking stage (P = 0.017) in Trps1-positive group compared to Trps1-negative group. Univariate analysis revealed that distant metastasis, MVD and Trps1 expression were associated with a lower 3-year overall survival rate and disease-free survival rate (P = 0.003, and P = 0.012 respectively). Furthermore, Trps1 and distant metastasis retained their significant prognostic effects on patients survival rate by multivariate analysis (P < 0.05).

Conclusions

Trps1 plays a crucial role in osteosarcoma angiogenesis, metastasis and clinical surgical stage. Trps1 can be a novel promising prognostic marker and therapeutic target, and antiangiogenic therapy which targets Trps1 molecule in patients with osteosarcoma may lead to improved prognosis and longer-term survival.