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Activated mTORC2/AKT signaling plays a role in hepatocellular carcinoma (HCC). Research has shown that TSC/mTORC1 and FOXO1 are distinct downstream effectors of AKT signaling in liver regeneration and metabolism. However, the mechanisms by which these pathways mediate mTORC2/AKT activation in HCC are not yet fully understood. Amplification and activation of c-MYC are key molecular events in HCC. In this study, we explored the roles of tuberous sclerosis complex/mTORC1 (TSC/mTORC1) and FOXO1 as downstream effectors of mTORC2/AKT1 in c-MYC-induced hepatocarcinogenesis. Using various genetic approaches in mice, we found that manipulating the FOXO pathway had a minimal effect on c-MYC-induced HCC. In contrast, loss of mTORC2 inhibited c-MYC-induced HCC, an effect that was completely reversed by ablation of TSC2, which activated mTORC1. Additionally, we discovered that p70/RPS6 and 4EBP1/eIF4E acted downstream of mTORC1, regulating distinct molecular pathways. Notably, the 4EBP1/eIF4E cascade is crucial for cell proliferation and glycolysis in c-MYC-induced HCC. We also identified centromere protein M (CENPM) as a downstream target of the TSC2/mTORC1 pathway in c-MYC-driven hepatocarcinogenesis, and its ablation entirely inhibited c-MYC-dependent HCC formation. Our findings demonstrate that the TSC/mTORC1/CENPM pathway, rather than the FOXO cascade, is the primary signaling pathway regulating c-MYC-driven hepatocarcinogenesis. Targeting CENPM holds therapeutic potential for treating c-MYC-driven HCC.

Patients with tuberous sclerosis complex (TSC) develop multi-organ disease manifestations, with kidney angiomyolipomas (AML) and cysts being one of the most common and deadly. Early and regular AML/cyst detection and monitoring are vital to lower TSC patient morbidity and mortality. However, the current standard of care involves imaging-based methods that are not designed for rapid screening, posing challenges for early detection. To identify potential diagnostic screening biomarkers of AML/cysts, we performed global untargeted metabolomics in blood samples from 283 kidney AML/cyst-positive or -negative TSC patients using mass spectrometry. We identified 7 highly sensitive chemical features, including octanoic acid, that predict kidney AML/cysts in TSC patients. Patients with elevated octanoic acid have lower levels of very long-chain fatty acids (VLCFAs), suggesting that dysregulated peroxisome activity leads to overproduction of octanoic acid via VLCFA oxidation. These data highlight AML/cysts blood biomarkers for TSC patients and offers valuable metabolic insights into the disease.

BACKGROUND: The TAND (Tuberous Sclerosis Complex [TSC]-Associated Neuropsychiatric Disorders) Checklist was developed as a clinical screener for neurodevelopmental disorders in TSC. Most studies have described patterns in older children and adults. This study sought to better understand behavioral concerns as measured by the TAND Checklist in young children with TSC. METHODS: We examined patterns of caregiver responses to the TAND Checklist in 90 toddlers with TSC (12 to 23 months n = 60; 24 to 36 months n = 30) through data collected during baseline visits across two TSC early intervention studies. RESULTS: Over 90% of caregivers reported at least one behavioral concern related to TAND. The number of concerns increased with age. Delayed language was the most frequently reported concern across ages (12 to 23 months: 58.3%, 24 to 36 months: 86.7%). Questions related to behavioral concerns were largely relevant in this age range, but questions in other areas, such as neuropsychological or academic function, were not. CONCLUSIONS: TAND symptoms are very common in toddlers with TSC, and these symptoms may increase with age. The TAND Checklist is a useful tool for identifying behavioral concerns efficiently, but several items and sections are not suited to younger children. Results support the development of an abbreviated form of the TAND Checklist for toddlers.

Tuberous Sclerosis Complex (TSC) is a multisystem neurocutaneous disorder with multiple neuro-ophthalmologic manifestations. The ophthalmologist plays an important role in the multi-disciplinary care team and should be familiar with this condition and its neuro-ophthalmic associations. A retrospective review of patients with TSC presenting to a neuro-ophthalmology clinic between 2015 and 2023 was performed. Patients had a diagnosis of TSC based on genetic testing or clinically definite disease (CDD) and at least one ophthalmic exam. We identified 135 patients. The mean age at the first exam was 14.1 ± 13.0 years. Seventy-three patients (54%) had retinal astrocytic hamartoma (RAH), bilateral in 33 (46%). Patients with TSC2 mutations and CDD were more likely to have RAHs than patients with TSC1 (p < .0005, <0.0001, respectively). In 60 patients where near-infrared reflectance (NIR) imaging guided optical coherence tomography (OCT) was performed, 23 (38%) had RAHs identified that were not seen on fundoscopy. Patients with subependymal giant cell astrocytoma (SEGA) were more likely to have RAHs than patients without (p = .037). The incidence of RAH and achromic patches was similar in patients with vs without TSC-associated neuropsychiatric disorders (TAND). Hamartoma were more common in patients with TSC2 mutations, CDD, and/or SEGA. NIR-guided OCT helps identify RAHs not seen on fundoscopy. Ocular involvement was not related to TANDs. [ABSTRACT FROM AUTHOR]

Background: Tuberous sclerosis complex is a genetic disorder caused by mutations in the TSC1 or TSC2 genes, affecting multiple systems. These genes produce proteins that regulate mTORC1 activity, essential for cell function and metabolism. While mTOR inhibitors have advanced treatment, maintaining long-term therapeutic success is still challenging. For over 20 years, significant progress has linked TSC1 or TSC2 gene mutations in stem cells to tuberous sclerosis complex symptoms. Methods: A comprehensive review was conducted using databases like Web of Science, Google Scholar, PubMed, and Science Direct, with search terms such as "tuberous sclerosis complex," "TSC1," "TSC2," "stem cell," "proliferation," and "differentiation." Relevant literature was thoroughly analyzed and summarized to present an updated analysis of the TSC1-TSC2 complex's role in stem cell fate determination and its implications for tuberous sclerosis complex. Results: The TSC1-TSC2 complex plays a crucial role in various stem cells, such as neural, germline, nephron progenitor, intestinal, hematopoietic, and mesenchymal stem/stromal cells, primarily through the mTOR signaling pathway. Conclusions: This review aims shed light on the role of the TSC1-TSC2 complex in stem cell fate, its impact on health and disease, and potential new treatments for tuberous sclerosis complex. [ABSTRACT FROM AUTHOR]

Background: Cardiac rhabdomyoma (RHM) is considered one of the most frequent benign heart tumors in children. However, encounters with cardiac RHM in clinical practice remain rare. Clinical information is primarily available in the form of single case reports or smaller studies with a shortage of large-scale reviews encompassing a substantial number of cases. Results: In order to congregate existing and future information on cardiac RHM we established a web-based cardiac RHM online registry using an online survey tool. In addition we integrated previously published data from individual case reports and case series. The evaluation of this paper is intended to provide a brief overview of the cohort that we have been able to include so far. Our findings mainly confirm the previous knowledge on cardiac RHM. At the same time, our cohort shows a clear heterogeneity in the treatment methods with regard to rhabdomyomas requiring therapy and revealed a bias between literature data and our registry data with regard to symptoms and need for therapy. Conclusion: In the view of the heterogeneity of treatment methods, a systematic overview of cardiac RHM is all the more important, especially as specific drug treatment options now exist. The registry should not just provide a comprehensive and informative overview of causes, time course, symptoms and therapeutic options of cardiac RHM but also facilitate information sharing among clinicians and researchers and serve as a basis for future clinical and pharmacological studies. [ABSTRACT FROM AUTHOR]

Malformations of cortical development encompass a broad range of disorders associated with abnormalities in corticogenesis. Widespread abnormalities in neuronal formation or migration can lead to small head size or microcephaly with disorganized placement of cell types. Specific, localized malformations are termed focal cortical dysplasias (FCD). Neurodevelopmental disorders are common in all types of malformations of cortical development with the most prominent being refractory epilepsy, behavioral disorders such as autism spectrum disorder (ASD), and learning disorders. Several genetic pathways have been associated with these disorders from control of cell cycle and cytoskeletal dynamics in global malformations to variants in growth factor signaling pathways, especially those interacting with the mechanistic target of rapamycin (mTOR), in FCDs. Despite advances in understanding these disorders, the underlying developmental pathways that lead to lesion formation and mechanisms through which defects in cortical development cause specific neurological symptoms often remains unclear. One limitation is the difficulty in modeling these disorders, as animal models frequently do not faithfully mirror the human phenotype. To circumvent this obstacle, many investigators have turned to three-dimensional human stem cell models of the brain, known as organoids, because they recapitulate early neurodevelopmental processes. High throughput analysis of these organoids presents a promising opportunity to model pathophysiological processes across the breadth of malformations of cortical development. In this review, we highlight advances in understanding the pathophysiology of brain malformations using organoid models. [ABSTRACT FROM AUTHOR]

Once believed to be the culprits of epileptogenic activity, the functional properties of balloon/giant cells (BC/GC), commonly found in some malformations of cortical development including focal cortical dysplasia type IIb (FCDIIb) and tuberous sclerosis complex (TSC), are beginning to be unraveled. These abnormal cells emerge during early brain development as a result of a hyperactive mTOR pathway and may express both neuronal and glial markers. A paradigm shift occurred when our group demonstrated that BC/GC in pediatric cases of FCDIIb and TSC are unable to generate action potentials and lack synaptic inputs. Hence, their role in epileptogenesis remained obscure. In this review, we provide a detailed characterization of abnormal non-neuronal cells including BC/GC, intermediate cells, and dysmorphic/reactive astrocytes found in FCDIIb and TSC cases, with special emphasis on electrophysiological and morphological assessments. Regardless of pathology, the electrophysiological properties of abnormal cells appear more glial-like, while others appear more neuronal-like. Their morphology also differs in terms of somatic size, shape, and dendritic elaboration. A common feature of these types of non-neuronal cells is their inability to generate action potentials. Thus, despite their distinct properties and etiologies, they share a common functional feature. We hypothesize that, although the exact role of abnormal non-neuronal cells in FCDIIb and TSC remains mysterious, it can be suggested that cells displaying more glial-like properties function in a similar way as astrocytes do, i.e., to buffer K+ ions and neurotransmitters, while those with more neuronal properties, may represent a metabolic burden due to high energy demands but inability to receive or transmit electric signals. In addition, due to the heterogeneity of these cells, a new classification scheme based on morphological, electrophysiological, and gene/protein expression in FCDIIb and TSC cases seems warranted. [ABSTRACT FROM AUTHOR]

Background: Tuberous Sclerosis Complex (TSC) is a rare genetic condition caused by mutation to TSC1 or TSC2 genes, with a population prevalence of 1/7000 births. TSC manifests behaviorally with features of autism, epilepsy, and intellectual disability. Resting state electroencephalography (EEG) offers a window into neural oscillatory activity and may serve as an intermediate biomarker between gene expression and behavioral manifestations. Such a biomarker could be useful in clinical trials as an endpoint or predictor of treatment response. However, seizures and antiepileptic medications also affect resting neural oscillatory activity and could undermine the utility of resting state EEG features as biomarkers in neurodevelopmental disorders such as TSC. Methods: This paper compares resting state EEG features in a cross-sectional cohort of young children with TSC (n = 49, ages 12–37 months) to 49 age- and sex-matched typically developing controls. Within children with TSC, associations were examined between resting state EEG features, seizure severity composite score, and use of GABA agonists. Results: Compared to matched typically developing children, children with TSC showed significantly greater beta power in permutation cluster analyses. Children with TSC also showed significantly greater aperiodic offset (reflecting nonoscillatory neuronal firing) after power spectra were parameterized using SpecParam into aperiodic and periodic components. Within children with TSC, both greater seizure severity and use of GABAergic antiepileptic medication were significantly and independently associated with increased periodic peak beta power. Conclusions: The elevated peak beta power observed in children with TSC compared to matched typically developing controls may be driven by both seizures and GABA agonist use. It is recommended to collect seizure and medication data alongside EEG data for clinical trials. These results highlight the challenge of using resting state EEG features as biomarkers in trials with neurodevelopmental disabilities when epilepsy and anti-epileptic medication are common. [ABSTRACT FROM AUTHOR]

Background: Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder affecting multiple organ systems, with a prevalence of 1:6,760–1:13,520 live births in Germany. On the molecular level, TSC is caused by heterozygous loss-of-function variants in either of the genes TSC1 or TSC2, encoding the Tuberin-Hamartin complex, which acts as a critical upstream suppressor of the mammalian target of rapamycin (mTOR), a key signaling pathway controlling cellular growth and metabolism. Despite the therapeutic success of mTOR inhibition in treating TSC-associated manifestations, studies with mTOR inhibitors in children with TSC above two years of age have failed to demonstrate beneficial effects on disease-related neuropsychological deficits. It has thus been hypothesized, that the critical time window for mTOR inhibitors may lie in early infancy, before TSC-related symptoms such as early-onset epilepsy and infantile spasms as sign of disruptive brain maturation occur. No controlled prospective clinical trials have evaluated the effect of pre-symptomatic mTOR inhibitor therapy on neuropsychological manifestations in TSC patients under two years of age. Methods: This two-arm, randomized, observer-blind, phase IIb national multicenter clinical trial aims at investigating the long-term neuropsychologic outcomes of pre-emptive mTOR inhibitor treatment in children diagnosed with TSC under four months of age. Sixty participants will be allocated to the trial with a 1:1 randomization ratio. The primary endpoint will be the neuropsychological outcome assessed by the cognitive scale of the Bayley Scales of Infant and Toddler Development III at 24 months of age compared to Standard of Care. Secondary endpoints include neuropsychologic outcomes at 12 months of age, seizure frequency, cardiac and cerebral tumor load, and safety assessments. Inclusion criteria are a definite TSC diagnosis and an age below four months at enrolment. The investigational medicinal product is sirolimus (Rapamune®), administered orally based on body surface area and surveilled by pharmacokinetic measurements, starting within the first four months of life and continuing until the second birthday. Conclusion: This study addresses a critical gap in understanding the impact of pre-emptive mTOR inhibitor therapy on neuropsychologic outcomes in young TSC patients, aiming to improve overall patient outcomes and quality of life. EUCT number: 2022–502332-39–00, Registered 22/06/2023, https://euclinicaltrials.eu/search-for-clinical-trials/?lang=en&EUCT=2022-502332-39-00 [ABSTRACT FROM AUTHOR]

Topical sirolimus is increasingly utilized off-licence to manage various dermatological conditions while avoiding typical adverse effects associated with systemic sirolimus. However, widespread use is limited by a highly heterogeneous evidence base of mixed quality. Our aim was to evaluate the current evidence base for the indications, efficacy and safety profile of topical sirolimus in dermatology. A literature search was conducted from 2005 to 4 July 2023, of English-language studies, with the following databases consulted: MEDLINE, PubMed, Embase, CENTRAL and EBSCO. Key words included 'topical', 'rapamycin', 'sirolimus' and 'dermatology'. Data on drug efficacy, concentration, side-effects, cointerventions and follow-up were extracted. The search identified 202 studies, 71 of which met the inclusion criteria. Efficacy of topical sirolimus was demonstrated in facial angiofibromas (799 patients) compared with placebo across multiple randomized controlled trials, with a predominant concentration of 0.1%. Evidence was mixed for use of sirolimus in port-wine stains (61 patients), with evidence of effectiveness for combined sirolimus and pulsed-dye laser. Multiple case reports demonstrated clinical improvement with topical sirolimus in cutaneous vascular abnormalities (33 patients) at a higher concentration of 1%. Other applications of topical sirolimus were predominantly case reports, demonstrating generally favourable outcomes. Topical sirolimus was generally well tolerated; most reported adverse effects were localized irritation and pruritus. Ointment-based preparations and once-daily dosing appeared to confer a better side-effect profile. Most high-quality data pertain to the efficacy of topical sirolimus in treating facial angiofibromas in tuberous sclerosis. Outcomes are generally promising in other indications, with good tolerability, but data quality is mixed. [ABSTRACT FROM AUTHOR]

Objective: To identify the disease-causing variant in a family with tuberous sclerosis complex (TSC). Methods: This study including a Han-Chinese pedigree recruited from the Third Xiangya Hospital, Central South University, Changsha, Hunan, China was conducted between February, 2019 and January, 2023. Detailed clinical examinations were performed on the proband and other family members of a Han-Chinese family with TSC. Whole exome sequencing of the proband and Sanger sequencing of all family members were performed, followed by variant pathogenicity prediction and conservation analysis. SWISS-MODEL and PyMOL software were used for protein modelling and creating the three-dimensional structure model illustration of the critical GTPase-activating protein (GAP) domain. The variant was classified following the American College of Medical Genetics and Genomics (ACMG) standards and guidelines. Results: The female proband exhibited typical features of TSC, including hypomelanotic macules, angiofibromas, shagreen patches, seizures, brain lesions, cognitive impairment, renal abnormalities, and cardiovascular abnormalities. A recurrent c.5126C>T variant in the TSC complex subunit 2 gene (TSC2) was identified as the genetic cause of TSC in this family, classified as “pathogenic” according to ACMG standards and guidelines. The c.5126C>T variant leads to an amino acid change from proline to leucine at position 1709 (p.P1709L) in the functional GAP domain of tuberin protein, which may impair tumor growth inhibition of the hamartin-tuberin complex. Conclusion: This study reported a Han-Chinese TSC patient with a recurrent variant TSC2 c.5126C>T (p.P1709L). These findings broaden the phenotypic spectrum of TSC caused by this variant and may contribute to improving TSC genetic diagnoses as well as understanding of its mechanisms. [ABSTRACT FROM AUTHOR]

Tuberous sclerosis complex (TSC) is a genetic condition characterized by both medical and neuropsychiatric diagnoses that emerge across the lifespan. As part of a clinical trial, caregivers of children with TSC were interviewed about their experiences navigating medical, school, and social services. Semistructured interviews (N = 20) with caregivers of children with TSC (27-60 months) were conducted upon exit from the study. The interviews covered topics related to experiences following diagnosis, interactions with providers, sources of information, and access to services and treatment. The main themes from the caregiver interviews included: (1) sources of information about TSC and treatment; (2) access to high-quality and expert medical care; (3) perception and diagnosis of TAND; (4) impact of epilepsy on daily life, intervention, and schooling; and (5) access to therapeutic services, compatible providers, and evaluations. Additionally, parents provided recommendations for other caregivers navigating their child's early treatment following diagnosis. These results reflect the importance of current research priorities for TSC stakeholders, including implementation of existing clinical guidelines, improved access to TSC expertise, and coordinated and integrated health care. [ABSTRACT FROM AUTHOR]

Background/Aim: Lymphangioleiomyomatosis (LAM) belongs to the perivascular epithelioid cell tumor (PEComa) family. The relationship between LAM and tuberous sclerosis complex (TSC) is of particular concern in a subset of women with clinically occult LAM involving the pelvic lymph nodes. This study aimed to investigate the clinicopathological features of incidental nodal LAM detected during the surgical staging of gynecological tumors. Patients and Methods: During the study period of 10 years, we identified 17 patients with pelvic nodal LAM that was incidentally detected during surgery for gynecological neoplastic lesions. We conducted immunostaining to assess the diagnostic utility of a panel of PEComa markers. Results: Two of the 17 patients (11.8%) were diagnosed with TSC before surgery without any pulmonary symptoms. During the follow-up, both patients developed pulmonary and extrapulmonary LAMs. All affected nodes were multiple and unilateral in the pelvic region. The mean nodal size was 5.4 mm, and the mean proportion of the area involved in the LAM was 34.1%. In two patients with TSC, the largest affected node measured 19.3 mm and 7.6 mm, respectively, and the proportion of the area replaced by LAM was 99% and 90%, respectively. The most frequently expressed markers were human melanoma black 45 and cathepsin K, which showed 100% positivity in all the examined cases. Conclusion: While most small nodal LAMs incidentally discovered during surgery have insignificant prognostic value, larger nodal LAMs occupying most of the nodal parenchyma at reproductive age should raise awareness of pulmonary and extrapulmonary LAMs as well as TSC. [ABSTRACT FROM AUTHOR]

Background/Objectives: Cardiac rhabdomyoma (CR), the most frequently occurring fetal cardiac tumor, is often an early marker of tuberous sclerosis complex (TSC). This study evaluates outcomes of fetuses with prenatally diagnosed cardiac tumors managed at a single tertiary center. Methods: Medical records of fetuses diagnosed with cardiac tumors between 2009 and 2024 were retrospectively reviewed. Results: Sixteen cases were identified, with a median follow-up of 6.7 years. TSC was confirmed in 14 cases (88%). Multiple tumors were observed in 13 cases (81%), while 3 cases (19%) had solitary tumors. Both non-TSC cases involved solitary tumors. Cardiac complications (arrhythmias, conduction disorders, and hemodynamic abnormalities) occurred in 38% of cases prenatally and 69% postnatally, with larger tumor diameters significantly associated with complications (p = 0.02). No fetal hydrops or mortality occurred; however, one child died at age five due to a seizure. Postnatal tumor regression occurred in 56% of cases and complete regression in 38% by a median age of 2.3 years (range: 0.6–4.4). One tumor remained stable. Brain MRI revealed TSC-related changes in all TSC-affected patients except one, who had a developmental brain anomaly. Most TSC patients experienced epilepsy (71%) and developmental delays. Conclusion: While CRs are typically benign and regress spontaneously, their strong association with TSC highlights the importance of early diagnosis and family counseling. TSC-related epilepsy and psychomotor delays significantly impair the quality of life. Early mTOR inhibitor therapy offers promise in mitigating TSC-related complications and improving outcomes. [ABSTRACT FROM AUTHOR]

There is a striking sex bias in the prevalence and severity of autism spectrum disorder (ASD) with 80% of diagnoses occurring in males. Because the molecular etiology of ASD is likely combinatorial, including interactions across multiple genetic and environmental factors, it is difficult to investigate the physiological mechanisms driving sex-specific differences. Loss of function mutations in TSC1 result in dysregulated mTORC1 signaling and underlie a multi-system disorder known as tuberous sclerosis (TSC). Interestingly, more than 50% of individuals diagnosed with TSC are also diagnosed with ASD, making TSC mutations one of the most prevalent monogenic causes of ASD. Mice harboring targeted deletion of Tsc1 selectively in cerebellar Purkinje neurons, referred to here as Tsc1mut/mut , have multiple ASD-linked behavioral impairments, including deficits in social interactions, motor coordination, and vocalizations. However, these ASD-linked behavioral deficits have only been investigated using male Tsc1mut/mut animals. Here, we used cohorts of male and female Tsc1mut/mut animals to determine if behavioral impairments, previously identified in this model, are similar across sex. Specifically, we measured balance and motor coordination and social interaction behaviors in two age groups across sex. We determined balance and motor coordination deficits are similar in male and female Tsc1mut/mut mice, and that deficits in the firing of Tsc1mut/mut Purkinje neurons located in the cerebellar vermis are also similar across sex. However, impairments in social approach behavior were found to be significantly more severe in Tsc1mut/mut males compared to females. These results indicate the selective deletion of Tsc1 in Purkinje neurons differentially impairs cerebellar circuits based on sex. [ABSTRACT FROM AUTHOR]

Network hypersynchrony is emerging as an important system-level mechanism underlying seizures, as well as cognitive and behavioural impairments, in children with structural brain abnormalities. We investigated patterns of single neuron action potential behaviour in 206 neurons recorded from tubers, transmantle tails of tubers and normal looking cortex in 3 children with tuberous sclerosis. The patterns of neuronal firing on a neuron-by-neuron (autocorrelation) basis did not reveal any differences as a function of anatomy. However, at the level of functional networks (cross-correlation), there is a much larger propensity towards hypersynchrony of tuber-tuber neurons than in neurons from any other anatomical site. This suggests that tubers are the primary drivers of adverse outcomes in children with tuberous sclerosis. [ABSTRACT FROM AUTHOR]

Tuberous sclerosis complex (TSC) is a rare genetic disorder characterized by the formation of benign tumors in various organs, particularly in the central nervous system. We aimed to delineate the molecular profile of Turkish individuals diagnosed with TSC by analyzing the TSC1 and TSC2 genes using next-generation sequencing (NGS). Sophia Genetics' Sophia Inherited Disease Panel was used to perform NGS on 22 individuals diagnosed with TSC and to identify pathogenic variants in the TSC1 and TSC2 genes. Among the 22 cases, mutations were found in 3 (13.6%) for TSC1 and in 16 (73%) for TSC2, while 3 (13.6%) exhibited no detectable mutations. Notably, one individual with a TSC2 mutation presented with angiofibroma, ungual fibroma, and pitted dental enamel, while another had cardiac rhabdomyoma. Autism spectrum disorders were observed in 6 (27%) with TSC2 mutations, including one with autistic behavior. Abnormal motor development was noted in 3 (13.6%), of which 2 had TSC2 mutations. Severe intellectual disability was found in 3 (13.6%) with TSC2 mutations, and developmental delay was seen in 2 (9%) with TSC2 mutations. Epileptic encephalopathy occurred in 3 (13.6%), with 2 having TSC2 mutations. Additionally, 6 (27%) exhibited drug resistance for focal seizures, with 5 of them having TSC2 mutations. These findings are consistent with other research indicating that TSC2 mutations are associated with a more severe phenotypic range compared to TSC1 mutations. Moreover, our analysis showed that some people with TSC1/TSC2 mutations did not match diagnostic criteria. This highlights the importance of genetic testing and molecular profiling in understanding the clinical variability and aiding in the management of TSC patients. [ABSTRACT FROM AUTHOR]

Objective Methods Results Significance Epilepsy surgery in the operculoinsular cortex is challenging due to the difficult delineation of the epileptogenic zone and the high risk of postoperative deficits.Pre‐ and postsurgical data from 30 pediatric patients who underwent operculoinsular cortex surgery at the Motol Epilepsy Center Prague from 2010 to 2022 were analyzed.Focal cortical dysplasia (FCD; n = 15, 50%) was the predominant cause of epilepsy, followed by epilepsy‐associated tumors (n = 5, 17%) and tuberous sclerosis complex (n = 2, 7%). In eight patients where FCD was the most likely etiology, the histology was negative. Seven patients (23%) displayed normal magnetic resonance imaging results. Seizures exhibited diverse semiology and propagation patterns (frontal, perisylvian, and temporal). The ictal and interictal electroencephalographic (EEG) findings were mostly extensive. Multimodal imaging and advanced postprocessing were frequently used. Stereo‐EEG was used for localizing the epileptogenic zone and eloquent cortex in 23 patients (77%). Oblique electrodes were used as guides for better neurosurgeon orientation. The epileptogenic zone was in the dominant hemisphere in 16 patients. At the 2‐year follow‐up, 22 patients (73%) were completely seizure‐free, and eight (27%) experienced a seizure frequency reduction of >50% (International League Against Epilepsy class 3 and 4). Fourteen patients (47%) underwent antiseizure medication tapering; treatment was completely withdrawn in two (7%). Nineteen patients (63%) remained seizure‐free following the definitive outcome assessment (median = 6 years 5 months, range = 2 years to 13 years 5 months postsurgery). Six patients (20%) experienced corona radiata or basal ganglia ischemia; four (13%) improved to mild and one (3%) to moderate hemiparesis. Two patients (7%) operated on in the anterior insula along with frontotemporal resection experienced major complications: pontine ischemia and postoperative brain edema.Epilepsy surgery in the operculoinsular cortex can lead to excellent patient outcomes. A comprehensive diagnostic approach is crucial for surgical success. Rehabilitation brings a great chance for significant recovery of postoperative deficits. [ABSTRACT FROM AUTHOR]

Objective Methods Results Significance Previous retrospective studies have reported vigabatrin‐associated brain abnormalities on magnetic resonance imaging (VABAM), although clinical impact is unknown. We evaluated the association between vigabatrin and predefined brain magnetic resonance imaging (MRI) changes in a large homogenous tuberous sclerosis complex (TSC) cohort and assessed to what extent VABAM‐related symptoms were reported in TSC infants.The Dutch TSC Registry and the EPISTOP cohort provided retrospective and prospective data from 80 TSC patients treated with vigabatrin (VGB) before the age of 2 years and 23 TSC patients without VGB. Twenty‐nine age‐matched non‐TSC epilepsy patients not receiving VGB were included as controls. VABAM, specified as T2/fluid‐attenuated inversion recovery hyperintensity or diffusion restriction in predefined brain areas, were examined on brain MRI before, during, and after VGB, and once in the controls (at approximately age 2 years). Additionally, the presence of VABAM accompanying symptoms was evaluated.Prevalence of VABAM in VGB‐treated TSC patients was 35.5%. VABAM‐like abnormalities were observed in 13.5% of all patients without VGB. VGB was significantly associated with VABAM (risk ratio [RR] = 3.57, 95% confidence interval [CI] = 1.43–6.39), whereas TSC and refractory epilepsy were not. In all 13 VGB‐treated patients with VABAM for whom posttreatment MRIs were available, VABAM entirely resolved after VGB discontinuation. The prevalence of symptoms was 11.7% in patients with VABAM or VABAM‐like MRI abnormalities and 4.3% in those without, implicating no significant association (RR = 2.76, 95% CI = .68–8.77).VABAM are common in VGB‐treated TSC infants; however, VABAM‐like abnormalities also occurred in children without either VGB or TSC. The cause of these MRI changes is unknown. Possible contributing factors are abnormal myelination, underlying etiology, recurrent seizures, and other antiseizure medication. Furthermore, the presence of VABAM (or VABAM‐like abnormalities) did not appear to be associated with clinical symptoms. This study confirms that the well‐known antiseizure effects of VGB outweigh the risk of VABAM and related symptoms. [ABSTRACT FROM AUTHOR]

Background: In clinical research, the most appropriate way to assess the effect of an intervention is to conduct a randomized controlled trial (RCT). In the field of rare diseases, conducting an RCT is challenging, resulting in a low rate of clinical trials, with a high frequency of early termination and unpublished trials. The aim of the EPISTOP trial was to compare outcomes in infants with tuberous sclerosis (TSC) who received vigabatrin preventively before the seizures onset with those who received it conventionally after. The study was designed as a prospective, multicentre, randomized clinical trial. However, ethics committees at four centres did not approve this RCT design, resulting in an open-label trial (OLT) in these four centres and an RCT in the other six centres. In this paper, we re-analyse the data from the EPISTOP trial using methods to investigate the influence of allocation bias on the results of the EPISTOP trial. Method: A bias-corrected analysis is used to support and strengthen the published results. We included a term representing the effect of selection bias as an influencing factor on the corresponding endpoint in the statistical model. Thus, the treatment effect estimates for the primary endpoint of time to first seizure and additional secondary endpoints are adjusted for the bias effect. Result: The bias-corrected analyses for the primary endpoint show that the estimated hazard ratio and associated confidence intervals are in a very similar range (original analysis: HR 2.91, 95%-CI [1.11 to 7.67], p-value 0.0306; bias-corrected analysis: HR 2.89, 95%-CI [1.10 to 7.58], p-value 0.0316). This was also the case for the secondary endpoints. Conclusion: The statistical re-analysis of the raw trial data therefore supports the published results and confirms that there is no additional bias introduced by randomization, thereby increasing the value of the results. However, this highlights that this aspect needs to be considered in future trials, especially in rare diseases, to avoid additional biases in an already small sample size where it may be difficult to reach significance. [ABSTRACT FROM AUTHOR]

PURPOSE: Patients age 1-21 years with relapsed or refractory solid and CNS tumors were assigned to phase II studies of molecularly targeted therapies on the National Cancer Institute-Children's Oncology Group (NCI-COG) Pediatric Molecular Analysis for Therapy Choice (MATCH) trial. Patients whose tumors harbored predefined genetic alterations in the phosphoinositide 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) pathway and lacked mitogen-activated protein kinase pathway activating alterations were treated with the PI3K/mTOR inhibitor samotolisib. METHODS: Patients received samotolisib twice daily in 28-day cycles until disease progression or unacceptable toxicity. A rolling 6 limited dose escalation was performed as, to our knowledge, this was the first pediatric study of samotolisib. The primary end point was the objective response rate; secondary end points included progression-free survival (PFS) and the recommended phase II dose and toxicity of samotolisib in children. RESULTS: A total of 3.4% (41/1,206) of centrally tested patients were matched to this arm. Seventeen patients were treated. Among treated patients, the most common diagnoses included osteosarcoma (n = 6) and high-grade glioma (n = 5) harboring alterations in phosphatase and tensin homolog (n = 6), PIK3CA (n = 5), and tuberous sclerosis complex 2 (n = 3). No objective responses or prolonged stable disease were observed. Three-month PFS was 12% (95% CI, 2 to 31). Two patients experienced dose-limiting toxicities (mucositis and pneumonitis). Dose level 2 (115 mg/m2/dose twice daily) was determined to be the recommended phase II dose of samotolisib in children. CONCLUSION: This nationwide study was successful at identifying patients and evaluating the efficacy of molecularly targeted therapy for rare molecular subgroups of patients in a histology-agnostic fashion. Unfortunately, there was no activity of samotolisib against tumors with PI3K/mTOR pathway alterations. Prospective trials such as the NCI-COG Pediatric MATCH are necessary to evaluate the efficacy of molecularly targeted therapies given their increasing use in clinical practice. [ABSTRACT FROM AUTHOR]

PURPOSE: The purpose of this article was to provide an overview of syndromic gliomas. DESIGN: The authors conducted a nonsystematic literature review. RESULTS: Cancer predisposition syndromes (CPSs) are genetic conditions that increase one's risk for certain types of cancer compared with the general population. Syndromes that can predispose one to developing gliomas include neurofibromatosis, Li-Fraumeni syndrome, Lynch syndrome, and tuberous sclerosis complex. The standard treatment for sporadic glioma may involve resection, radiation therapy, and/or alkylating chemotherapy. However, DNA-damaging approaches, such as radiation and alkylating agents, may increase the risk of secondary malignancies and other complications in patients with CPSs. In some cases, depending on genetic aberrations, targeted therapies or immunotherapeutic approaches may be considered. Data on clinical characteristics, therapeutic strategies, and prognosis of syndromic gliomas remain limited. CONCLUSION: In this review, we provide an overview of syndromic gliomas with a focus on management for patients with CPSs and the role of novel treatments that can be considered. [ABSTRACT FROM AUTHOR]

Simple Summary: Clear cell renal cell carcinoma is a kidney cancer with high incidence rates in the western world. There is an increasing research base fueling the modern application of therapy to treat this cancer. Despite the traditional surgical interventions available for treatment, more is now understood about its metastases and optimal treatment strategies. The treatment of clear cell renal cell carcinoma is quickly advancing to ensure that patients receive personalized cancer therapy specific to their solid tumor. While surgical interventions remain the dominant treatment modality, adjuvant drug therapies have shown promising results, especially for patients with advanced disease. Clear cell renal cell carcinoma is the most common form of kidney cancer, accounting for 75% of malignant kidney tumors, and is generally associated with poor patient outcomes. With risk factors including smoking, obesity, and hypertension, all of which have a high prevalence in the United States and Europe, as well as genetic factors including tuberous sclerosis complex and Von Hippel–Lindau syndrome, there is an increasing need to expand our present understanding. The current clear cell renal cell carcinoma knowledge is outdated, with obsolete diagnostic criteria and moderately invasive surgical treatments still prevailing, partially ascribed to its resistance to chemotherapy and radiation therapy. The standard of treatment relies on surgical intervention, including radical nephrectomy and partial nephrectomy, while more recent treatments target neoplastic growth pathways and immune regulation checkpoints. [ABSTRACT FROM AUTHOR]

The finding of a simple kidney cyst in a child can pose a diagnostic and management challenge for pediatric nephrologists, urologists, and primary care providers. The reported prevalence varies from 0.22 to 1% in large ultrasonography-based series of more than 10,000 children each. The true prevalence, however, may be higher or lower, as factors such as variations in referral patterns, indications for ultrasonography, or technical considerations could impact prevalence rates. For many patients, simple kidney cysts may be found incidentally when imaging is performed for another indication. Although simple cysts can occur in children, they may also represent the first sign of autosomal dominant polycystic kidney disease (ADPKD) or other less common cystic kidney diseases. Definitive guidelines regarding the evaluation and monitoring of children with simple kidney cysts have not been established. The desire on the part of the practitioner and/or parents to establish a definitive diagnosis should be balanced with the cost and inconvenience of repeated imaging and visits with specialists. The goals of this review are to (1) outline the definition, epidemiology, clinical presentation, and natural history of simple kidney cysts in childhood; (2) describe clinical features that could suggest a diagnosis other than a simple kidney cyst; and (3) present a suggested framework for evaluating and monitoring of children with one or more simple kidney cysts. [ABSTRACT FROM AUTHOR]

Epilepsy is prevalent, and seizure control is challenging in patients with tuberous sclerosis complex (TSC). Cenobamate (CBM) has proven efficacy in several studies; however, its benefit in the TSC population is not known. We performed a retrospective review of patients with TSC who received adjunctive CBM for seizure treatments. We assessed treatment efficacy by comparing seizure frequencies three months before CBM (baseline) and those at 3-, 6-, 12-, and 18- month follow-ups. We identified 70 patients with TSC receiving CBM and excluded 16 with insufficient data. Fifty-four patients aged 2 to 39 years, with an average baseline seizure of 66.1 ± 88.9 per month, were analyzed. Treatment retention rates at 3, 6, 12, and 18 months were 94.4%, 79.6%, 66.7%, 44.4%, and responder rates (proportions of patients who remained on treatment and had ≥50% seizure reduction) were 38.1%, 51.7%, 53.1%, and 59.1%, respectively. Seizure-free rates at these respective follow-ups were 7.1%, 13.8%, 6.3%, and 9.1%. For patients experiencing reduced seizures, the mean percentage of change ranged from 61.5% to 74.6%. Side effects were common (64.8%), particularly sedation (42.6%), behavioral disturbance (24.1%), and gastrointestinal disturbance (22.2%). Most patients in this study showed seizure reduction; however, the overall responder and seizure-free rates were lower than the literature, likely due to the unique underlying epileptogenesis in TSC and the challenges of tolerating CBM. The lower treatment retention rates signal areas for improvement in concurrent medication adjustment practices. [ABSTRACT FROM AUTHOR]

Tuberous sclerosis complex (TSC) is a multisystemic disorder caused by inactivating variants in the mTOR pathway inhibitor genes TSC1 and TSC2. Individuals with TSC are predisposed to benign tumors in multiple organs as well as TSC-associated neuropsychiatric disorders (TAND) and epilepsy. Pathogenic variants in TSC2 are typically associated with a more severe phenotype compared with TSC1 ; the TSC2 R905Q variant has been shown to be an exception, where patients have been reported to present with unusually mild TSC features that may be undetected. We studied the TSC phenotype of a 13-year-old individual and three family members with a TSC2 c.2714G>A (R905Q) pathogenic variant. Patient 1 presented with severe medically refractory epilepsy without tubers or subependymal nodules and only mild dermatologic features of TSC missed on virtual examinations. Her mother and maternal aunt (Patients 2 and 3–diagnosed after age 50 years) presented with a mild phenotype, with dermatologic features and TAND. Her maternal uncle (Patient 4–diagnosed at age 47 years) displayed the most severe phenotype, presenting with intellectual disability, medically refractory epilepsy, obsessive-compulsive disorder, post-traumatic stress disorder, and psychosis. This study expands the possible phenotypic spectrum of TSC2 R905Q variant, demonstrating an association with severe epilepsy without associated neuroradiological stigmata. This presentation highlights the possibility of occult focal cortical dysplasia in TSC and emphasizes the importance of genetic testing in individuals with severe epilepsy. Moreover, a late adult diagnosis was subsequently made in other family members allowing for appropriate TSC surveillance to occur. [ABSTRACT FROM AUTHOR]

Tuberous sclerosis complex (TSC)–related skeletal abnormalities are understudied. Awareness of skull thickening in patients with TSC is important from the surgical standpoint because a thick skull might complicate craniotomy. This study aimed to discover if patients with TSC are generally prone to skull thickening by retrospectively investigating the frequency and characteristics of skull thickening in these patients. Patients with TSC ages 10 to 60 years who underwent magnetic resonance imaging in the neurosurgery, dermatology, or pediatrics clinic between 2010 and 2021 were identified. Two control groups were used for comparison: one with patients with unruptured intracranial aneurysms to serve as control without antiseizure medication exposure and one with non-TSC epilepsy as control with antiseizure medication exposure. In all patients, thickness of frontal, parietal, temporal, and occipital bones was measured at a fixed location of each bone on T2-weighted axial images. Inclusion criteria were fulfilled by 29 patients. Frontal and temporal bones of the TSC group were significantly thicker than those of either control group. Skull thickening was significantly associated with intracerebral calcification, but not with age, sex, or antiseizure medication exposure. Focal skull thickening was associated with the presence of a subcortical calcification. Patients with TSC have skull thickening, which is often linked to intracerebral calcification. The presence of skull thickening may require modification of surgical approach during craniotomy. Skull thickening and the underlying intracerebral calcification likely share a common precipitating factor given their relationship. Future studies are warranted to clarify the genetic underpinnings of this relationship and even broader skeletal abnormalities in TSC. [ABSTRACT FROM AUTHOR]

Background: Radiomics refers to the extraction of quantitative information from medical images and is most commonly utilized in oncology to provide ancillary information for solid tumor diagnosis, prognosis, and treatment response. The traditional radiomic pipeline involves segmentation of volumes of interest with comparison to normal brain. In other neurologic disorders, such as epilepsy, lesion delineation may be difficult or impossible due to poor anatomic definition, small size, and multifocal or diffuse distribution. Tuberous sclerosis complex (TSC) is a rare genetic disease in which brain magnetic resonance imaging (MRI) demonstrates multifocal abnormalities with variable imaging and epileptogenic features. Purpose: The purpose of this study was to develop a radiomic workflow for identification of abnormal brain regions in TSC, using a whole‐brain atlas‐based approach with generation of heatmaps based on signal deviation from normal controls. Methods: This was a retrospective pilot study utilizing high‐resolution whole‐brain 3D FLAIR MRI datasets from retrospective enrollment of tuberous sclerosis complex (TSC) patients and normal controls. Subjects underwent MRI including high‐resolution 3D FLAIR sequences. Preprocessing included skull stripping, coregistration, and intensity normalization. Using the Brainnetome and Harvard‐Oxford atlases, brain regions were parcellated into 318 discrete regions. Expert neuroradiologists spatially labeled all tubers in TSC patients using ITK‐SNAP. The pyradiomics toolbox was used to extract 88 radiomic features based on IBSI guidelines, comparing tuber‐affected and non‐tuber‐affected parenchyma in TSC patients, as well as normal brain tissue in control patients. For model training and validation, regions with tubers from 20 TSC patients and 30 normal control subjects were randomly divided into two training sets (80%) and two validation sets (20%). Additional model testing was performed on a separate group of 20 healthy controls. LASSO (least absolute shrinkage and selection operator) was used to perform variable selection and regularization to identify regions containing tubers. Relevant radiomic features selected by LASSO were combined to produce a radiomic score ω, defined as the sum of squared differences from average control group values. Region‐specific ω scores were converted to heat maps and spatially coregistered with brain MRI to reflect overall radiomic deviation from normal. Results: The proposed radiomic workflow allows for quantification of deviation from normal in 318 regions of the brain with the use of a summative radiomic score ω. This score can be used to generate spatially registered heatmaps to identify brain regions with radiomic abnormalities. The pilot study of TSC showed radiomic scores ω that were statistically different in regions containing tubers from regions without tubers/normal brain (p < 0.0001). Our model exhibits an AUC of 0.81 (95% confidence interval: 0.78–0.84) on the testing set, and the best threshold obtained on the training set, when applied to the testing set, allows us to identify regions with tubers with a specificity of 0.91 and a sensitivity of 0.60. Conclusion: We describe a whole‐brain atlas‐based radiomic approach to identify abnormal brain regions in TSC patients. This approach may be helpful for identifying specific regions of interest based on relatively greater signal deviation, particularly in clinical scenarios with numerous or poorly defined anatomic lesions. [ABSTRACT FROM AUTHOR]

Background: Tuberous sclerosis complex (TSC) is a rare autosomal dominant genetic disorder that affects multiple organs. However, precise diagnosis is challenging owing to the lack of truly pathognomonic symptoms. This retrospective observational study aimed to explore the real-world diagnostic flow of Japanese patients with TSC by examining time to diagnosis (TTD) from the onset of each TSC-related manifestation to TSC diagnosis and the role of TSC clinic in timely diagnosis, using data from a health insurance database. Methods: Analyses were performed using data derived from the JMDC Claims Database between January 2005 and December 2020. Patients with at least 1 confirmed diagnosis of TSC were stratified into 2 cohorts: Cohort 1 included cases diagnosed after 2 years of age, and Cohort 2 included cases diagnosed before 2 years of age. The primary endpoint was TTD in Cohorts 1 and 2. Secondary endpoints were the incidence of each manifestation in Cohort 1 and the incidence and risk ratios of TSC-unrelated symptoms in Cohort 2. Results: Cohorts 1 and 2 included 106 and 42 patients, respectively. In Cohort 1, patients with a renal tumor diagnosis as a primary TSC-related manifestation had the longest TTD with a wide range (median: 23 months to up to 91 months); patients with non-specific TSC-related manifestations such as brain tumor/intraventricular tumor, epilepsy, or intellectual disabilities also experienced a delay in TTD. In patients with TSC who developed epilepsy, those attending facilities with a TSC clinic were diagnosed with TSC more quickly than those attending facilities without a TSC clinic (median: 11.5 and 19.0 months, respectively; p = 0.0379). Epilepsy was the manifestation with the highest incidence (29.2%) among Cohort 1 patients, while cardiac rhabdomyoma had the highest incidence (54.8%) among Cohort 2 patients. Dry skin was the most common TSC-unrelated symptom in Cohort 2, with a 1.7-fold higher incidence rate than that in controls (N = 619,936). Conclusion: Japanese patients with renal lesions as a primary TSC-related manifestation had the longest delay for a definitive diagnosis of TSC, followed by those with epilepsy, brain tumor/intraventricular tumor, and intellectual disabilities. The TSC clinic played an important role in the early diagnosis of TSC. [ABSTRACT FROM AUTHOR]

Epilepsy affects approximately 1% of the world population. Patients have recurrent seizures, increased physical and psychiatric comorbidities, and higher mortality rate than the general population. Over the last 40 years, research has resulted in 20 new antiseizure medications (ASMs) approved between 1990 and 2018. In spite of this, up to one-third of patients (~ 1 million patients in the USA) have drug-resistant epilepsy (DRE), with little change between 1982 and 2018, a period of intense new ASM development. A minority of patients with DRE may benefit from surgical treatment, but this specialized care remains challenging to scale. Therefore, the greatest hope for breakthroughs for patients with DRE is in pharmacologic therapies. Recently, several advances promise to change the outcomes for patients with DRE. Cenobamate, a drug with dual mechanisms of modulating sodium channel currents and GABA-A receptors, achieves 90–100% seizure reduction in 25–33% of patients with focal DRE, a response not observed with other ASMs. Fenfluramine, a serotonin-acting drug, dramatically reduces the frequency of convulsive seizures in Dravet syndrome, a devastating developmental epileptic encephalopathy with severe DRE. Both drugs reduce mortality. In addition, the possibility of DRE prevention was recently raised in patients with tuberous sclerosis complex, a relatively common genetic form of epilepsy. A paradigm shift is emerging in the treatment of epilepsy. Seizure freedom has become attainable in a significant proportion of patients with focal DRE, and dramatic seizure reduction has been achieved in a developmental encephalopathy. Coupled with a rich pipeline of new compounds under clinical development, the long sought-after breakthrough in the treatment of epilepsy may finally be in sight. [ABSTRACT FROM AUTHOR]

Little is known about the influence of (impaired) neurodevelopment on cognitive aging. We here used a mouse model for tuberous sclerosis (TS) carrying a heterozygous deletion of the Tsc2 gene. Loss of Tsc2 function leads to mTOR hyperactivity in mice and patients. In a longitudinal behavioral analysis, we found premature decline of hippocampus‐based cognitive functions together with a significant reduction of immediate early gene (IEG) expression. While we did not detect any morphological changes of hippocampal projections and synaptic contacts, molecular markers of neurodegeneration were increased and the mTOR signaling cascade was downregulated in hippocampal synaptosomes. Injection of IGF2, a molecule that induces mTOR signaling, could fully rescue cognitive impairment and IEG expression in aging Tsc2+/− animals. This data suggests that TS is an exhausting disease that causes erosion of the mTOR pathway over time and IGF2 is a promising avenue for treating age‐related degeneration in mTORopathies. [ABSTRACT FROM AUTHOR]

Tuberous sclerosis complex (TSC) is a rare autosomal dominant neurocutaneous disease. Arterial hypertension is one of its uncommon complications, which is supposed to be caused by renal cysts or angiomyolipomas. Few studies have been reported in the literature on renal artery stenosis (RAS) as the cause of hypertension in TSC. Hence, we reported a boy who presented with uncontrolled hypertension under five anti‐hypertension drugs and was diagnosed with TSC complicated with left RAS. His high blood pressure was relieved by percutaneous transluminal renal angioplasty (PTRA). In one and a half years follow‐up, his blood pressure was normal whilst he took four anti‐hypertensive drugs. In conclusion, children with TCS complicated with hypertension should be carefully screened for RAS, which might be relieved by percutaneous balloon dilatation. [ABSTRACT FROM AUTHOR]

Objective: This study evaluated the accuracy of non-invasive prenatal testing (NIPT-SGDs) for dominant monogenic genetic diseases associated with fetal structural abnormalities and to assess the feasibility of clinical application. Methods: Pregnant women requiring prenatal diagnosis due to fetal structural abnormalities were enrolled. Maternal peripheral blood was analyzed for cell-free DNA (cfDNA) using coordinative allele-aware target enrichment sequencing (COATE-seq). This assessed fetal allele depth distribution, fraction and variation ratio. The variation's origin was then determined to obtain fetal variation information. Finally, NIPT-SGDs results were confirmed via invasive prenatal diagnosis (IPD). Results: Upon examination of 113 samples using NIPT-SGDs, COATE-seq successfully analyzed 112 for fetal variation, excluding one due to hemolysis. The study detected six positive cases, yielding a 5.36% detection rate. These disorders included tuberous sclerosis complex (TSC1 and TSC2 being its causative genes), Noonan syndrome (PTPN11), polycystic kidney disease (PKD1), and Kabuki syndrome (KMT2D), occurring twice each, except for Noonan and polycystic kidney disease. Two false positives were due to the mother being a genetic mosaicism. Compared to invasive whole-exome sequencing (WES), NIPT-SGDs did not detect nine positive cases of IPD dominant monogenic diseases, accurately identifying 90.18% (101/112) of the actual positive and negative cases. Conclusion: Our findings demonstrate the clinical utility of NIPT-SGDs using COATE-seq in effectively identifying fetuses with dominant single-gene disorders. Furthermore, this method can be applied to all fetuses. [ABSTRACT FROM AUTHOR]

• Surveillance MRI is needed to monitor for TSC associated renal angiomyolipomas. • However, MRI of the abdomen is not approved for patients with VNS therapy. • We studied abdominal MRIs performed in typical VNS exclusion zones. • We found they were not associated with adverse events or VNS dysfunction. Individuals with tuberous sclerosis complex (TSC) often present with refractory epilepsy and may be undergoing treatment with vagus nerve stimulation (VNS) to control seizures. Surveillance magnetic resonance imaging (MRI) is necessary to monitor for the renal angiomyolipomas associated with TSC; however, MRI of the abdomen is not approved for patients withVNS therapy. We have many TSC patients with refractory epilelpsy who benefitted from VNS therapy, so we developed an MRI protocol that allows MRI of the abdomen to be performed in these patients to permit safe imaging of their kidneys. Here we report our results using this protocol. We performed a retrospective review for all TSC patients seen from 01/01/1997 to 10/01/2022 at a single center to determine VNS implantation status. Patients with VNS implants and abdomen imaging performed according to the protocol for kidney surveillance were included. Sixteen patients with 48 total MRIs of the abdomen were found: 34 (71 %) scans were conducted under sedation and 14 (29 %) without sedation. None of the patients reported any adverse effects (pain or discomfort). No instances of VNS dysfunction were noted when re-interrogating the device immediately after completion of the imaging studies or at later neurology follow-up appointments. All MRI scans were of good quality for interpretation. Abdominal MRIs performed in typical VNS exclusion zones were not associated with adverse events or VNS dysfunction. We believe this protocol is safe and permits the best method for monitoring renal disease in TSC patients with VNS. [ABSTRACT FROM AUTHOR]

Lymphangioleiomyomatosis is an ultra-rare disease mainly affecting women of childbearing age. The MILES trial showed the efficacy of sirolimus, an mTOR inhibitor, in stabilising lung function in patients with lymphangioleiomyomatosis. Drug toxicity and development of resistance are potential limitations of therapy with sirolimus. Nintedanib is a multikinase inhibitor that inhibits PDGFR, which is active in human and murine lymphangioleiomyomatosis lesions. We aimed to investigate the activity and safety of nintedanib in patients with lymphangioleiomyomatosis. This phase 2, open-label, single-arm study was conducted at MultiMedica IRCCS, a national referral university centre for rare pulmonary diseases in Milan, Italy. Eligible participants were aged 18 years and older and had sporadic or tuberous sclerosis complex-associated lymphangioleiomyomatosis with progressive pulmonary function decline in the past year despite treatment with sirolimus or treatment naive. Patients received nintedanib 150 mg orally twice per day, with a possible reduction to 100 mg twice per day in case of side-effects or hepatoxicity, for 12 months, followed by a period of 12 additional months without study treatment. The primary endpoint was the change in FEV 1 (FEV 1 slope in L) over 12 months. This study is registered with ClinicalTrials.gov , NCT03062943. From Oct 14, 2016, to Dec 13, 2019, 35 female patients (mean age 50 years [SD 11]) entered the study, 30 of whom were eligible and received nintedanib. After 12 months, 22 patients completed the treatment, 19 of whom also completed the 12 months of follow-up. FEV 1 remained stable after one year of treatment (predicted mean difference 0·001 L [95% CI –0·063 to 0·066]; p=0·97). During the 12 months off treatment, a slight decline in FEV 1 was observed (predicted mean difference –0·076 L [95% CI –0·149 to –0·004]; p=0·040). The most frequent adverse events were nausea (15 [50%] patients), diarrhoea (eight [26%]), and abdominal pain (two [7%]). No serious adverse events were observed during the treatment period. Our findings suggest that nintedanib did not improve FEV 1 , but that the treatment was generally well tolerated. These results might support nintedanib as a second-line therapy in patients not controlled by standard treatment with mTOR inhibitors. Further investigation, such as a non-inferiority trial comparing nintedanib and sirolimus could help to better clarify the role of this drug as a potential alternative treatment. Boehringer-Ingelheim. [ABSTRACT FROM AUTHOR]

The document published in the Annals of the American Thoracic Society explores the occurrence of Hemoptysis Associated with Sexual Activity (HASA) in patients with Lymphangioleiomyomatosis (LAM). The study found that approximately 10% of patients with LAM experienced HASA, with a higher prevalence among premenopausal women. HASA had a significant impact on patients' quality of life and sexual health, leading to avoidance of sexual activity in some cases. The study suggests that clinicians should inquire about HASA when evaluating patients with LAM. [Extracted from the article]

Background: Tuberous sclerosis complex (TSC) is an autosomal dominant genetic disorder characterized by mutations in the TSC1 and TSC2 genes, leading to the dysregulation of the mammalian target of rapamycin (mTOR) pathway. This dysregulation results in the development of benign tumors across multiple organ systems and poses significant neurodevelopmental challenges. The clinical manifestations of TSC vary widely and include subependymal giant cell astrocytomas (SEGAs), renal angiomyolipomas (AMLs), facial angiofibromas (FAs), and neuropsychiatric conditions such as autism spectrum disorder (ASD). mTOR inhibitors, notably everolimus, have become central to TSC management, with documented efficacy in reducing the sizes of SEGAs and AMLs and showing promise in addressing additional TSC-related symptoms. Case Presentation: We report the case of an 11-year-old male diagnosed with TSC, presenting with hallmark features including hypopigmented macules, early-onset infantile spasms, SEGA, and AMLs. Initial interventions included adrenocorticotropic hormone (ACTH) therapy and sodium valproate for seizure management and a minimally invasive keyhole craniotomy for SEGA reduction. At age 12, oral everolimus therapy was introduced to address both SEGA recurrence risk and ASD-related social deficits. Over the course of 24 weeks, a reduction in the size and erythema of the patient's FAs was observed, alongside improvements in social engagement, suggesting potential added benefits of systemic mTOR inhibition beyond tumor control. Results: Treatment with everolimus over a 24-month period led to significant reductions in both FA and AML size, as well as measurable improvements in ASD-associated behaviors. Therapeutic drug monitoring maintained serum levels within the effective range, minimizing adverse effects and underscoring the tolerability and feasibility of long-term everolimus administration. Conclusions: This case underscores the efficacy of oral everolimus in reducing FA size in a pediatric TSC patient, with broader therapeutic benefits that support the potential of mTOR inhibition as a multi-targeted strategy for TSC management. Further studies are needed to explore the full range of applications and long-term impact of mTOR inhibitors in TSC care. [ABSTRACT FROM AUTHOR]

Lymphangioleiomyomatosis (LAM) is a rare, slowly progressing, low-grade metastatic tumor primarily affecting women. Currently, vascular endothelial growth factor–D (VEGF-D) is the only validated diagnostic biomarker, enabling diagnosis of LAM without the need for lung biopsy in appropriate clinical settings. However, VEGF-D concentrations are normal in about 30% of patients, rendering it insufficient for diagnosing all cases of LAM. There remains a need to identify more non-invasive, safe, sensitive, and specific biomarkers associated with LAM. Therefore, it is imperative to explore novel non-invasive, safe, and specific diagnostic methods for LAM. This article aims to review biomarkers associated with LAM, including potential biomarkers newly discovered or showing advancements in classical biomarkers widely used in LAM, and discuss their application in LAM diagnosis, assessment of disease severity, prediction of treatment response, and prognosis.淋巴管平滑肌瘤病 （LAM） 是一种罕见的、进展缓慢的低级别转移性肿瘤，主要影响女性。目前，血管内皮生长因子-D （VEGF-D） 是唯一经过验证的诊断生物标志物，无需在适当的临床环境中进行肺活检即可诊断 LAM。然而，约 30% 患者的 VEGF-D 浓度正常，不足以诊断所有 LAM 病例。仍然需要确定与 LAM 相关的更多无创、安全、敏感和特异性的生物标志物。因此，当务之急是探索新型无创、安全和特异性的 LAM 诊断方法。本文旨在回顾与 LAM 相关的生物标志物，包括新发现的潜在生物标志物或显示出 LAM 中广泛使用的经典生物标志物的进展，并讨论它们在 LAM 诊断、疾病严重程度评估、治疗反应预测和预后中的应用。 [ABSTRACT FROM AUTHOR]

Background: The TSC1 gene encodes a growth inhibitory protein hamartin, which plays a crucial role in negative regulation of the activity of mTORC1 (mechanistic target of rapamycin complex 1). TSC1 has been associated with tuberous sclerosis complex (TSC). This study aims to investigate the association between TSC1 variants and common epilepsy. Methods: Trio-based whole-exome sequencing was performed in epilepsy patients without acquired etiologies from the China Epilepsy Gene 1.0 Project platform. The pathogenicity of the variants was evaluated according to the American College of Medical Genetics and Genomic (ACMG) guidelines. Results: Two TSC1 de novo variants, including c.1498 C > T/p.Arg500* and c.2356 C > T/p.Arg786*, were identified in two patients with developmental and epileptic encephalopathy (DEE). The patients exhibited frequent seizures and neurodevelopmental delay. Additionally, we identified two heterozygous TSC1 variants that affected four individuals with focal epilepsy from two unrelated families. The four probands did not present any typical symptom of TSC and had normal brain MRI findings. The four variants were absent in the Genome Aggregation Database (gnomAD) and were predicted to be damaging with a in silico prediction tool. Based on the ACMG guidelines, the four variants were evaluated to be "pathogenic" or "likely pathogenic". Of the patients in the China Epilepsy Gene 1.0 Project, 22 patients carried TSC1 variants and were diagnosed with TSC. The ratio of patients carrying TSC1 variants with or without TSC is about 5:1. Conclusions: TSC1 is potentially associated with common epilepsy without tuberous sclerosis. [ABSTRACT FROM AUTHOR]

Tuberous sclerosis complex (TSC) is targeted to the lysosomal membrane, where it hydrolyzes RAS homolog-mTORC1 binding (RHEB) from its GTP-bound to GDP-bound state, inhibiting mechanistic target of rapamycin complex 1 (mTORC1). Loss-of-function mutations in TSC cause TSC disease, marked by excessive tumor growth. Here, we overcome a high degree of continuous conformational heterogeneity to determine the 2.8-Å cryo-electron microscopy (cryo-EM) structure of the complete human TSC in complex with the lysosomal recruitment factor WD repeat domain phosphoinositide-interacting protein 3 (WIPI3). We discover a previously undetected amino-terminal TSC1 HEAT repeat dimer that clamps onto a single TSC wing and forms a phosphatidylinositol phosphate (PIP)-binding pocket, which specifically binds monophosphorylated PIPs. These structural advances provide a model by which WIPI3 and PIP-signaling networks coordinate to recruit TSC to the lysosomal membrane to inhibit mTORC1. The high-resolution TSC structure reveals previously unrecognized mutational hotspots and uncovers crucial insights into the mechanisms of TSC dysregulation in disease. [ABSTRACT FROM AUTHOR]

To stimulate cell growth, the protein kinase complex mTORC1 requires intracellular amino acids for activation. Amino-acid sufficiency is relayed to mTORC1 by Rag GTPases on lysosomes, where growth factor signaling enhances mTORC1 activity via the GTPase Rheb. In the absence of amino acids, GATOR1 inactivates the Rags, resulting in lysosomal detachment and inactivation of mTORC1. We demonstrate that in human cells, the release of mTORC1 from lysosomes depends on its kinase activity. In accordance with a negative feedback mechanism, activated mTOR mutants display low lysosome occupancy, causing hypo-phosphorylation and nuclear localization of the lysosomal substrate TFE3. Surprisingly, mTORC1 activated by Rheb does not increase the cytoplasmic/lysosomal ratio of mTORC1, indicating the existence of mTORC1 pools with distinct substrate specificity. Dysregulation of either pool results in aberrant TFE3 activity and may explain nuclear accumulation of TFE3 in epileptogenic malformations in focal cortical dysplasia type II (FCD II) and tuberous sclerosis (TSC). [Display omitted] • Pharmacological inhibition prevents lysosomal mTORC1 release during amino acid depletion • A specific mTORC1 pool controls lysosomal mTORC1 levels in a Rag-dependent manner • Activating mTOR mutations result in hypo-phosphorylated and nuclear TFE3 • Nuclear TFE3 is found in dysmorphic cells in brain malformations with active mTOR Zwakenberg et al. show that mTORC1 auto-regulates its presence on lysosomes. Inhibition of mTOR results in lysosomal mTORC1 accumulation. Active mTOR mutants, on the other hand, have a high cytosolic/lysosomal ratio, leading to nuclear TFE3 accumulation. Auto-regulation is mediated by an mTORC1 pool distinct from the one activated through loss of TSC and may involve GATOR1. [ABSTRACT FROM AUTHOR]

Activated mTORC2/AKT signaling plays a role in hepatocellular carcinoma (HCC). Research has shown that TSC/mTORC1 and FOXO1 are distinct downstream effectors of AKT signaling in liver regeneration and metabolism. However, the mechanisms by which these pathways mediate mTORC2/AKT activation in HCC are not yet fully understood. Amplification and activation of c-MYC are key molecular events in HCC. In this study, we explored the roles of tuberous sclerosis complex/mTORC1 (TSC/mTORC1) and FOXO1 as downstream effectors of mTORC2/AKT1 in c-MYC-induced hepatocarcinogenesis. Using various genetic approaches in mice, we found that manipulating the FOXO pathway had a minimal effect on c-MYC-induced HCC. In contrast, loss of mTORC2 inhibited c-MYC-induced HCC, an effect that was completely reversed by ablation of TSC2, which activated mTORC1. Additionally, we discovered that p70/RPS6 and 4EBP1/eIF4E acted downstream of mTORC1, regulating distinct molecular pathways. Notably, the 4EBP1/eIF4E cascade is crucial for cell proliferation and glycolysis in c-MYC-induced HCC. We also identified centromere protein M (CENPM) as a downstream target of the TSC2/mTORC1 pathway in c-MYC-driven hepatocarcinogenesis, and its ablation entirely inhibited c-MYC-dependent HCC formation. Our findings demonstrate that the TSC/mTORC1/CENPM pathway, rather than the FOXO cascade, is the primary signaling pathway regulating c-MYC-driven hepatocarcinogenesis. Targeting CENPM holds therapeutic potential for treating c-MYC-driven HCC. [ABSTRACT FROM AUTHOR]

Subependymal giant cell astrocytoma (SEGA) is a rare, low‐grade glioma typically associated with tuberous sclerosis (TS) and mutations in the TSC1 or TSC2 genes. It is characterized by an intraventricular location, an expansive growth pattern, and the expression of glial and neural markers. TTF‐1 expression is considered a sensitive marker of SEGA, likely reflecting its origin from progenitor cells in the caudothalamic groove. We report a case of SEGA with unusual immunohistochemical and molecular features in a 20‐year‐old man with no signs or family history of TS. The tumor was located in the anterior horn of the right ventricle and obstructed the foramen of Monro. Histologically, it exhibited an expansive growth pattern and was composed of cells with ovoid nuclei and abundant eosinophilic cytoplasm. Immunohistochemically, the tumor cells were positive for GFAP and S‐100 protein, weakly positive for SOX2, focally positive for synaptophysin, and negative for TTF‐1, neurofilament protein, NeuN, EMA, chromogranin, and BCOR. Scattered OLIG2‐positive neoplastic cells were also observed. Molecular analysis revealed no pathogenic mutations or copy number variations in the analyzed 174 genes, including TSC1/2, except for a variant of unknown significance in BAP1. The histopathological features and immunohistochemical profile suggested SEGA, despite the absence of TTF‐1 expression and TSC1/2 mutations. The diagnosis was confirmed by DNA methylation profiling, which assigned the tumor to the methylation class “subependymal giant cell astrocytoma with TSC1/TSC2 alterations” with a calibrated score of 0.95. This case highlights the potential diagnostic pitfall of SEGA lacking TTF‐1 expression and emphasizes the importance of considering this entity in the differential diagnosis of intraventricular tumors, even in the absence of TS and characteristic molecular alterations. The existence of TTF‐1 negative SEGAs reveals that these tumors might also derive from TTF‐1 negative cells in the subpendymal region. [ABSTRACT FROM AUTHOR]

Background: Tuberous sclerosis complex (TSC) can present prenatally, often with cardiac rhabdomyomas, which, if large, may cause complications such as hydrops fetalis and reduced cardiac output. Prenatal treatment of these lesions with mTOR inhibitors, approved for other TSC manifestations, is under investigation. We hypothesize that mTOR inhibitors could help manage or prevent other TSC-related conditions, particularly neurological issues like epilepsy and CNS lesions, potentially improving neurodevelopmental outcomes. However, the safety of prenatal mTOR treatment remains a concern, especially for foetal development, and limited data are available on neurological outcomes. Methods: We conducted a literature review using PubMed, EMBASE, and Cochrane CENTRAL, focusing on studies involving mTOR inhibitors for prenatal TSC management. The search included case reports and series involving pregnant women diagnosed with TSC or early manifestations like cardiac rhabdomyomas. Keywords included "mTOR Inhibitor", "Rapamycin", "tuberous sclerosis complex", "prenatal", and "rhabdomyoma". Results: Three prenatal mouse studies and eight papers reporting on ten pregnant women treated with mTOR inhibitors were identified. Conclusions: The literature confirms that prenatal mTOR inhibitors may reduce cardiac rhabdomyomas. However, further studies are needed to explore their broader potential, particularly in preventing neurological complications, while carefully considering their impact on intrauterine growth and neurodevelopment. [ABSTRACT FROM AUTHOR]

Background and purpose: Around 30% of patients with epilepsy show drug‐resistant epilepsy (DRE). While cannabidiol has demonstrated efficacy as an adjunctive treatment in Dravet syndrome (DS), Lennox–Gastaut Syndrome (LGS), and epilepsy related to tuberous sclerosis complex (TSC), its more global effectiveness in adult patients with DRE apart from these three specific contexts needs to be clarified. Methods: We conducted a retrospective study at the epilepsy unit of Pitié Salpêtrière Hospital. Patients initiating pharmaceutical cannabidiol treatment and followed for at least 1 year were included. Patients were categorized into "authorized" (LGS, DS, or TSC) and "off‐label" groups. Cannabidiol effectiveness and tolerance were compared between groups, and characteristics of responders (patients with >50% reduction in seizure frequency) in the off‐label group were examined. Results: Ninety‐one patients, followed by a median duration of 24 months, were included. A total of 35.2% of the patients were in the authorized group. No significant differences were observed in responder rates between groups (31.3% vs. 35.6%, p = 0.85) and retention rates at 1 year (75.0% vs. 74.6%, p = 0.97). Sleepiness was more commonly reported in the authorized group (50.0% vs. 22.0%, p = 0.01), with no other significant differences. Among off‐label patients (n = 59), clobazam co‐prescription was more prevalent in responders (71.4% vs. 28.9%, p = 0.002). Conclusion: Our findings suggest that cannabidiol may benefit all adult patients with DRE, particularly those already receiving clobazam. Randomized controlled trials are warranted in off‐label patients to validate these observational findings. [ABSTRACT FROM AUTHOR]

The mammalian target of Rapamycin complex 1 (mTORC1) is a serine/threonine kinase that couples nutrient and growth factor signaling to the cellular control of metabolism and plays a fundamental role in aberrant proliferation in cancer. mTORC1 has previously been considered an "on/off" switch, capable of phosphorylating the entire pool of its substrates when activated. However, recent studies have indicated that mTORC1 may be active toward its canonical substrates, eukaryotic translation initiation factor 4E-binding protein 1 (4EBP1) and S6 kinase (S6K), involved in mRNA translation and protein synthesis, and inactive toward TFEB and TFE3, transcription factors involved in the regulation of lysosome biogenesis, in several pathological contexts. Among these conditions are Birt–Hogg–Dubé syndrome (BHD) and, recently, tuberous sclerosis complex (TSC). Furthermore, increased TFEB and TFE3 nuclear localization in these syndromes, and in translocation renal cell carcinomas (tRCC), drives mTORC1 activity toward the canonical substrates, through the transcriptional activation of the Rag GTPases, thereby positioning TFEB and TFE3 upstream of mTORC1 activity toward 4EBP1 and S6K. The expanding importance of TFEB and TFE3 in the pathogenesis of these renal diseases warrants a novel clinical grouping that we term "TFEopathies." Currently, there are no therapeutic options directly targeting TFEB and TFE3, which represents a challenging and critically required avenue for cancer research. [ABSTRACT FROM AUTHOR]

Tuberous sclerosis complex (TSC) is an autosomal dominant neurodevelopmental disorder and multisystem disease caused by pathogenic DNA alterations in the TSC1 and TSC2 tumor suppressor genes. A molecular genetic diagnosis of TSC confirms the clinical diagnosis, facilitating the implementation of appropriate care and surveillance. TSC1 and TSC2 encode the core components of the TSC1/2 complex (TSC1/2), a negative regulator of the mechanistic target of rapamycin (MTOR) complex 1 (TORC1). Functional analysis of the effects of TSC1 and TSC2 variants on TORC1 activity can help establish variant pathogenicity. We searched for pathogenic alterations to TSC1 and TSC2 in DNA isolated from 116 individuals with a definite clinical diagnosis of TSC. Missense variants and in-frame deletions were functionally assessed. Pathogenic DNA alterations were identified in 106 cases (91%); 18 (17%) in TSC1 and 88 (83%) in TSC2. Of these, 35 were novel. Disruption of TSC1/2 activity was demonstrated for seven TSC2 variants. Molecular diagnostics confirms the clinical diagnosis of TSC in a large proportion of cases. Functional assessment can help establish variant pathogenicity and is a useful adjunct to DNA analysis. [ABSTRACT FROM AUTHOR]