1
|
Ancora C, Marchi M, Bonardi CM, Sartori G, Lopreiato R, Zuccarello D, D'Errico I, Nosadini M, Sartori S, Boniver C, Toldo I, Salviati L. Electroclinical Features in Two Novel STRADA Patients and a Functional Yeast Assay for the Validation of Missense STRADA Mutations. Pediatr Neurol 2023; 148:152-156. [PMID: 37722301 DOI: 10.1016/j.pediatrneurol.2023.08.018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 08/11/2023] [Accepted: 08/14/2023] [Indexed: 09/20/2023]
Abstract
Loss of function of the STRADA gene, an upstream mTOR inhibitor, causes a rare neurodevelopmental disorder characterized by polyhydramnios, megalencephaly, and symptomatic epilepsy (PMSE syndrome). Patients display a homogeneous phenotype including early-onset drug-resistant epilepsy, severe psychomotor delay, multisystemic comorbidities, and increased risk of premature death. The administration of sirolimus, an mTOR inhibitor, is helpful in controlling seizures in this syndrome. We report the electroclinical phenotype of two novel patients and the development of a yeast model to validate the pathogenicity of missense variants. Patient 1 harbored a missense STRADA variant and had a peculiar electroclinical phenotype with a relatively mild epilepsy course. Patient 2 harbored a truncating STRADA variant and showed a typical PMSE phenotype and a favorable response to early treatment with sirolimus. When we modeled the p.(Ser264Arg) STRADA change in its yeast homolog SPS1, it impaired SPS1 function. The results underlie the importance of a timely molecular diagnosis in these patients and show that yeast is a simple yet effective model to validate the pathogenicity of missense variants.
Collapse
Affiliation(s)
- Caterina Ancora
- Pediatric Neurology and Neurophysiology Unit, Department of Women's and Children's Health, University of Padua, Padua, Italy
| | - Marco Marchi
- Clinical Genetics Unit, Department of Women's and Children's Health, University of Padua, Padua, Italy; Clinical Genetics Lab, Città della Speranza Pediatric Research Institute, Padua, Italy
| | - Claudia Maria Bonardi
- Pediatric Neurology and Neurophysiology Unit, Department of Women's and Children's Health, University of Padua, Padua, Italy
| | - Geppo Sartori
- Department of Biomedical Sciences, University of Padua, Padua, Italy
| | | | - Daniela Zuccarello
- Clinical Genetics Unit, Department of Women's and Children's Health, University of Padua, Padua, Italy
| | | | - Margherita Nosadini
- Pediatric Neurology and Neurophysiology Unit, Department of Women's and Children's Health, University of Padua, Padua, Italy
| | - Stefano Sartori
- Pediatric Neurology and Neurophysiology Unit, Department of Women's and Children's Health, University of Padua, Padua, Italy
| | - Clementina Boniver
- Pediatric Neurology and Neurophysiology Unit, Department of Women's and Children's Health, University of Padua, Padua, Italy
| | - Irene Toldo
- Pediatric Neurology and Neurophysiology Unit, Department of Women's and Children's Health, University of Padua, Padua, Italy.
| | - Leonardo Salviati
- Clinical Genetics Unit, Department of Women's and Children's Health, University of Padua, Padua, Italy; Clinical Genetics Lab, Città della Speranza Pediatric Research Institute, Padua, Italy
| |
Collapse
|
2
|
Abstract
Focal cortical dysplasias (FCDs) constitute a prevalent cause of intractable epilepsy in children, and is one of the leading conditions requiring epilepsy surgery. Despite recent advances in the cellular and molecular biology of these conditions, the pathogenetic mechanisms of FCDs remain largely unknown. The purpose if this work is to review the molecular underpinnings of FCDs and to highlight potential therapeutic targets. A systematic review of the literature regarding the histologic, molecular, and electrophysiologic aspects of FCDs was conducted. Disruption of the mammalian target of rapamycin (mTOR) signaling comprises a common pathway underlying the structural and electrical disturbances of some FCDs. Other mechanisms such as viral infections, prematurity, head trauma, and brain tumors are also posited. mTOR inhibitors (i.e., rapamycin) have shown positive results on seizure management in animal models and in a small cohort of patients with FCD. Encouraging progress has been achieved on the molecular and electrophysiologic basis of constitutive cells in the dysplastic tissue. Despite the promising results of mTOR inhibitors, large-scale randomized trials are in need to evaluate their efficacy and side effects, along with additional mechanistic studies for the development of novel, molecular-based diagnostic and therapeutic approaches.
Collapse
Affiliation(s)
- Isaac Marin-Valencia
- Department of Neurology and Neurotherapeutics, and Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas, U.S.A
| | | | | |
Collapse
|