Tuberous Sclerosis Complex Patient Research Articles

Counselling in tuberous sclerosis complex: A survey on content and satisfaction in the Netherlands.

Tuberous sclerosis complex (TSC) is a highly variable condition and its clinical features cannot reliably be predicted from the genotype. Counselling of parents of a child with TSC is challenging because of the variability of the condition and the changing outlook due to new treatment options. This study explored current counselling strategies in TSC in the Netherlands, with the aim of developing a recommendation for counselling. We performed a nationwide survey using digital questionnaires. Questionnaires were sent to parents of children diagnosed with TSC, and to medical doctors involved in counselling, both no more than ten years prior to the study. Questions focused on general information about the child with TSC, medical doctors involved in counselling, type of information provided, mode of providing information, and recommendations for improvement of counselling. Parents of 34 children diagnosed with TSC (7 prenatally) and 18 medical doctors from different departments responded to the questionnaires. Almost all parents were informed on the neurological and cardiac symptoms of TSC, other symptoms were mentioned less often. Satisfaction on counselling was higher when more information on the variability of TSC was provided, preferentially during a clinical visit, when emotional support was provided, and when parents were notified of the TSC patient society. Information on the variability in expression and quality of life is highly demanded by (expecting) parents of a child with TSC. Furthermore, reference should be made to institutions such as the support organisation for patients and social services for questions and support.

Multifocal renal cell carcinoma associated with multiple simple renal cysts: A rare presentation

Multifocal renal cell carcinoma associated with multiple simple renal cysts: A rare presentation - ACHR- Print ISSN No: - 2581-5725 Online ISSN No:- 2456-9267 Article DOI No:- 10.18231/2456-9267.2019.0016, IP Archives of Cytology and Histopathology Research-IP Arch Cytol Histopathol Res

Neuron-Glia Interactions Increase Neuronal Phenotypes in Tuberous Sclerosis Complex Patient iPSC-Derived Models.

SummaryTuberous sclerosis complex (TSC) is a rare neurodevelopmental disorder resulting from autosomal dominant mutations in the TSC1 or TSC2 genes, leading to a hyperactivated mammalian target of rapamycin (mTOR) pathway, and gray and white matter defects in the brain. To study the involvement of neuron-glia interactions in TSC phenotypes, we generated TSC patient induced pluripotent stem cell (iPSC)-derived cortical neuronal and oligodendrocyte (OL) cultures. TSC neuron mono-cultures showed increased network activity, as measured by calcium transients and action potential firing, and increased dendritic branching. However, in co-cultures with OLs, neuronal defects became more apparent, showing cellular hypertrophy and increased axonal density. In addition, TSC neuron-OL co-cultures showed increased OL cell proliferation and decreased OL maturation. Pharmacological intervention with the mTOR regulator rapamycin suppressed these defects. Our patient iPSC-based model, therefore, shows a complex cellular TSC phenotype arising from the interaction of neuronal and glial cells and provides a platform for TSC disease modeling and drug development.

Rhinencephalon changes in tuberous sclerosis complex.

Despite complex olfactory bulb embryogenesis, its development abnormalities in tuberous sclerosis complex (TSC) have been poorly investigated. Brain MRIs of 110 TSC patients (mean age 11.5years; age range 0.5-38years; 52 female; 26 TSC1, 68 TSC2, 8 without mutation identified in TSC1 or TSC2, 8 not tested) were retrospectively evaluated. Signal and morphological abnormalities consistent with olfactory bulb hypo/aplasia or with olfactory bulb hamartomas were recorded. Cortical tuber number was visually assessed and a neurological severity score was obtained. Patients with and without rhinencephalon abnormalities were compared using appropriate parametric and non-parametric tests. Eight of110 (7.2%) TSC patients presented rhinencephalon MRI changes encompassing olfactory bulb bilateral aplasia (2/110), bilateral hypoplasia (2/110), unilateral hypoplasia (1/110), unilateral hamartoma (2/110), and bilateral hamartomas (1/110); olfactory bulb hypo/aplasia always displayed ipsilateral olfactory sulcus hypoplasia, while no TSC patient harboring rhinencephalon hamartomas had concomitant forebrain sulcation abnormalities. None of the patients showed overt olfactory deficits or hypogonadism, though young age and poor compliance hampered a proper evaluation in most cases. TSC patients with rhinencephalon changes had more cortical tubers (47 ± 29.1 vs 26.2 ± 19.6; p = 0.006) but did not differ for clinical severity (p = 0.45) compared to the other patients of the sample. Olfactory bulb and/or forebrain changes are not rare among TSC subjects. Future studies investigating clinical consequences in older subjects (anosmia, gonadic development etc.) will define whether rhinencephalon changes are simply an imaging feature among the constellation of TSC-related brain changes or a feature to be searched for possible implications in the management of TSC subjects.

Efficacy and Safety of Mammalian Target of Rapamycin Inhibitor Use—Long-term Follow-up of First Tuberous Sclerosis Complex Patient Treated De Novo With Sirolimus After Kidney Transplantation: A Case Report

Mammalian target of rapamycin inhibitors (mTORI) are increasingly used in the treatment of tuberous sclerosis complex (TSC) and as immunosuppressants after organ transplantation. In TSC patients, mTORI are the treatment of choice after kidney transplantation. It is still under debate if benefits from long-term mTORI use will not be limited by side effects. Materials and methodsWe report long-term follow-up data of the first TSC patient after kidney transplantation treated with sirolimus de novo. In 2005, a female patient was transplanted with a kidney graft after bilateral nephrectomy due to angiomyolipoma. Initial immunosuppressive treatment consisted of antithymocyte globulin, methylprednisolone, tacrolimus, and, due to TSC diagnosis, sirolimus. Creatinine level at discharge was 1.2 mg/dL. ResultsLong-term mTORI use resulted in skin lesion regression (angiofibromas, “confetti” skin lesions, shagreen patch) and disease stabilization in brain, abdominal, and chest magnetic resonance imaging/computed tomography scans. Pulmonary function tests showed improvement in restriction and slow deterioration in obstruction and diffusion parameters. Sirolimus related adverse reactions were hyperlipidemia and hypertriglyceridemia and respiratory and urinary tract infections. No gastrointestinal or hematologic symptoms occurred. Sirolimus concentrations ranged between 1.7 and 8.2 ng/mL (mean 4.01 ± 2.09 ng/mL). Since 2009 proteinuria and slow increase in creatinine level have been observed. No biopsy was performed to establish etiology and potential association with mTORI. In 2017 creatinine level was 2.2 mg/dL. ConclusionThe case of the patient confirms clinical effectiveness and acceptable safety of long-term mTORI treatment. Long-term mTORI use requires meticulous patient observation to optimize dosage, achieve immunosuppressive effect, and improve TSC manifestations with minimal side effects.

Characterization of developmental defects in the forebrain resulting from hyperactivated mTOR signaling by integrative analysis of transcriptomic and proteomic data

Hyperactivated mTOR signaling in the developing brain has been implicated in multiple forms of pathology including tuberous sclerosis complex (TSC). To date, various phenotypic defects such as cortical lamination irregularity, subependymal nodule formation, dysmorphic astrocyte differentiation and dendritic malformation have been described for patients and animal models. However, downstream networks affected in the developing brain by hyperactivated mTOR signaling have yet to be characterized. Here, we present an integrated analysis of transcriptomes and proteomes generated from wild-type and Tsc1/Emx1-Cre forebrains. This led to comprehensive lists of genes and proteins whose expression levels were altered by hyperactivated mTOR signaling. Further incorporation of TSC patient data followed by functional enrichment and network analyses pointed to changes in molecular components and cellular processes associated with neuronal differentiation and morphogenesis as the key downstream events underlying developmental and morphological defects in TSC. Our results provide novel and fundamental molecular bases for understanding hyperactivated mTOR signaling-induced brain defects which can in turn facilitate identification of potential diagnostic markers and therapeutic targets for mTOR signaling-related neurological disorders.

Tuft of white hair dissappearance in a TSC patient treated with everolimus for SEGA

Objective: Tuberous sclerosis complex (TSC) predisposes to development of lesions within multiple organ systems, including brain, kidneys, heart, lungs, skin. Evidence supports and ongoing studies are further evaluating the role of mTOR inhibitors in the treatment of a wide spectrum of disease manifestations, including reduction in tumor volume (Subependimal giant cell astrocytomas - SEGAs, renal angiomyolipoma) and epilepsy improvement, lung function and skin manifestations, including facial angiofibromas. Methods: We report a 16 years old male with normal intellect who was diagnosed with definite TSC based on: multiple hypomelanic macules, facial angiofibromas, shagreen patch, cortical tubers, subependimal nodules, SEGA>1cm. The patient also has epilepsy with focal seizures (frequency 2 seizures/month). The patient also presented a tuft of white hair located in the vertex area of the head. He was treated with Everolimus for the growing subependimal giant cell astrocytoma (SEGA) associated to Tuberous Sclerosis Complex (TSC). Results: The results in this case were: SEGA volume reduction (brain MRI was repeated 3 months after the dose has been established) and cosmetic benefit – starting second day after treatment onset (angiofibromas became pale), consolidated at 3 month of treatment (almost not visible). Another good effect of Everolimus treatment was clinically relevant reduction in overall seizure frequency (one seizures/6 months). In the first 6 months of treatment the disappearance of the white hair tuft was noted. Conclusion: Everolimus provides a non-invasive method to treat SEGA or renal growing tumors associated to TSC. We describe a dermatologic positive effect of Everolimus – the disappearance of the tuft of white hair. This is a very rare clinical manifestation that may be associated to TSC clinical picture. In a PubMed search using the key words “everolimus dermatological effects”, “everolimus white hair”, “everolimus hair”, we did not find any other case reporting white hair disappearance under Everolimus treatment.

Bone Size and Quality Regulation: Concerted Actions of mTOR in Mesenchymal Stromal Cells and Osteoclasts.

SummaryThe bone size and quality, acquired during adolescent growth under the influence of anabolic hormones, growth factors, and nutrients, determine the height and bone stability and forecast osteoporosis risks in late life. Yet bone size and quality control mechanisms remain enigmatic. To study the roles of mammalian target of rapamycin (mTOR) signaling, sensor of growth factors and nutrients, in bone size and quality regulation, we ablated Tsc1, a suppressor of mTOR, in mesenchymal stromal cells (MSCs), monocytes, or their progenies osteoblasts and osteoclasts. mTOR activation in MSCs, but much less in osteoblasts, increased bone width and mass due to MSC hyperproliferation, but decreased bone length and mineral contents due to defective MSC differentiation. mTOR activation promotes bone mineral accretion by inhibiting osteoclast differentiation and activity directly or via coupling with MSCs. Tuberous sclerosis complex patient studies confirmed these findings. Thus, mTOR regulates bone size via MSCs and bone quality by suppressing catabolic activities of osteoclasts.

Abnormal Neural Progenitor Cells Differentiated from Induced Pluripotent Stem Cells Partially Mimicked Development of TSC2 Neurological Abnormalities.

SummaryTuberous sclerosis complex (TSC) is a disease featuring devastating and therapeutically challenging neurological abnormalities. However, there is a lack of specific neural progenitor cell models for TSC. Here, the pathology of TSC was studied using primitive neural stem cells (pNSCs) from a patient presenting a c.1444-2A>C mutation in TSC2. We found that TSC2 pNSCs had higher proliferative activity and increased PAX6 expression compared with those of control pNSCs. Neurons differentiated from TSC2 pNSCs showed enlargement of the soma, perturbed neurite outgrowth, and abnormal connections among cells. TSC2 astrocytes had increased saturation density and higher proliferative activity. Moreover, the activity of the mTOR pathway was enhanced in pNSCs and induced in neurons and astrocytes. Thus, our results suggested that TSC2 heterozygosity caused neurological malformations in pNSCs, indicating that its heterozygosity might be sufficient for the development of neurological abnormalities in patients.

Detection of TSC1/TSC2 gene mutations among patients with tuberous sclerosis complex by Ion Torrent semiconductor sequencing

To develop and validate a method for mutation screening and prenatal diagnosis of TSC1/TSC2 mutations among patients with tuberous sclerosis complex (TSC) by Ion Torrent semiconductor sequencing. Potential mutations of SC1/TSC2 gene was detected in 2 TSC families and 1 sporadic TSC patient using an Ion Torrent PGM sequencer. Candidate variants were validated by Sanger sequencing. The corresponding site of TSC2 in the fetus of family 2 was also detected with Sanger sequencing. Ion Torrent semiconductor sequencing has identified a probably pathogenic TSC2 mutation (c.311-312insGCTG) in the patient from family 1, and a probably pathogenic TSC2 mutation (c.1790A>G) in the patient of family 2. Targeted Ion Torrent PGM sequencing is an accurate and efficient method to detect TSC1/TSC2 mutations in TSC.

Meta-analysis of stomatitis in clinical studies of everolimus: incidence and relationship with efficacy

Everolimus, an oral mammalian target of rapamycin (mTOR) inhibitor, is used to treat solid tumors and tuberous sclerosis complex (TSC). Stomatitis, an inflammation of the mucous membranes of the mouth, is a common adverse event associated with mTOR inhibitors, including everolimus. We conducted a meta-analysis of data from seven randomized, double-blind phase 3 clinical trials of everolimus to determine the clinical impact of stomatitis on efficacy and safety. Data were pooled from the safety sets of solid tumor [breast cancer (BOLERO-2 and BOLERO-3), renal cell carcinoma (RECORD-1), carcinoid tumors (RADIANT-2), and pancreatic neuroendocrine tumors (RADIANT-3)] and TSC studies (EXIST-1 and EXIST-2). Data from solid tumor trials and TSC trials were analyzed separately. The rate of stomatitis was 67% in the solid tumor trials (973/1455 patients) and 70% in the TSC trials (110/157 patients). Most stomatitis events were grade 1/2, with grade 3/4 events reported in only 9% (solid tumor trials) and 8% (TSC trials) of patients. Low TSC patient numbers prevented an in-depth evaluation of stomatitis and response. In the solid tumor trials, most first stomatitis episodes (89%; n = 870) were observed within 8 weeks of starting everolimus. Patients with stomatitis occurring within 8 weeks of everolimus initiation had longer progression-free survival (PFS) than everolimus-treated patients without stomatitis in BOLERO-2 {8.5 versus 6.9 months, respectively; hazard ratio (HR), 0.78 [95% confidence interval (CI), 0.62-1.00]} and RADIANT-3 [13.9 versus 8.3 months, respectively; HR, 0.70 (95% CI, 0.48-1.04)]. A similar trend was observed in RECORD-1 [HR, 0.90 (95% CI, 0.66-1.22)] and RADIANT-2 [HR, 0.87 (95% CI, 0.61-1.22)] but not in BOLERO-3 [HR, 1.01 (95% CI, 0.75-1.36)]. Stomatitis did not adversely affect PFS, supporting the administration of everolimus in accordance with standard management guidelines.

Targeted Next Generation Sequencing reveals previously unidentified TSC1 and TSC2 mutations.

BackgroundTuberous sclerosis complex (TSC) is an autosomal dominant disorder caused by mutations in TSC1 and TSC2. Conventional DNA diagnostic screens identify a TSC1 or TSC2 mutation in 75 - 90% of individuals categorised with definite TSC. The remaining individuals either have a mutation that is undetectable using conventional methods, or possibly a mutation in another as yet unidentified gene.MethodsHere we apply a targeted Next Generation Sequencing (NGS) approach to screen the complete TSC1 and TSC2 genomic loci in 7 individuals fulfilling the clinical diagnostic criteria for definite TSC in whom no TSC1 or TSC2 mutations were identified using conventional screening methods.ResultsWe identified and confirmed pathogenic mutations in 3 individuals. In the remaining individuals we identified variants of uncertain clinical significance. The identified variants included mosaic changes, changes located deep in intronic sequences and changes affecting promoter regions that would not have been identified using exon-only based analyses.ConclusionsTargeted NGS of the TSC1 and TSC2 loci is a suitable method to increase the yield of mutations identified in the TSC patient population.Electronic supplementary materialThe online version of this article (doi:10.1186/s12881-015-0155-4) contains supplementary material, which is available to authorized users.

The prevalence of pica in tuberous sclerosis complex.

BackgroundPica and Tuberous sclerosis complex (TSC) are rare disorders. We carried out a population survey of pica in our TSC patient population.FindingsPica was identified in four percent of cases of TSC. It was associated with adult onset or persistence into adulthood, epilepsy, severe learning difficulties and anaemia.ConclusionsPica in TSC is a rare disorder and a coherent history may be difficult to obtain from patients. The prevalence of pica is likely to be underdiagnosed. Pica is a recognised feature in adults with TSC and prompt recognition of this disorder should allow better management of patients with TSC.

A shower of second hit events as the cause of multifocal renal cell carcinoma in tuberous sclerosis complex.

Tuberous sclerosis complex (TSC) is a genetic disorder characterized by seizures and tumor formation in multiple organs, mainly in the brain, skin, kidney, lung and heart. Renal cell carcinoma (RCC) occurs in ∼3% of TSC patients, and typically develops at age <50. Here we describe genetic findings in two TSC patients with multiple renal tumors, each of whom had the germline mutation TSC2 p.R905Q. The first (female) TSC patient had a left followed by a right nephrectomy at ages 24 and 27. Both kidneys showed multifocal TSC-associated papillary RCC (PRCC). Targeted, next-generation sequencing (NGS) analysis of TSC2 in five tumors (four from the left kidney, one from the right) showed loss of heterozygosity in one tumor, and four different TSC2 point mutations (p.E1351*, p.R1032*, p.R1713H, c.4178_4179delCT) in the other four samples. Only one of the 11 other tumors available from this patient had one of the TSC2 second hit mutations identified. Whole-exome analysis of the five tumors identified a very small number of additional mutated genes, with an average of 3.4 nonsilent coding, somatic mutations per tumor, none of which were seen in >1 tumor. The second (male) TSC patient had bilateral partial nephrectomies (both at age 36), with similar findings of multifocal PRCC. NGS analysis of TSC2 in two of these tumors identified a second hit mutation c.2355+1G>T in one sample that was not seen in other tumors. In conclusion, we report the first detailed genetic analysis of RCCs in TSC patients. Molecular studies indicate that tumors developed independently due to various second hit events, suggesting that these patients experienced a 'shower' of second hit mutations in TSC2 during kidney development leading to this severe phenotype.

Chordoid meningioma in a pediatric patient with tuberous sclerosis complex.

Meningeal tumors are rare in childhood, comprising less than 4.2% of all pediatric primary intracranial tumors.1 Fourteen histological subtypes of meningiomas exist in the World Health Organization (WHO) classification system.2 Chordoid meningioma (CM) is a rare meningiomal variant characterized histologically by features that mimic chordoma and other chordoid neoplasms.2 Chordoid meningiomal tumors tend to exhibit local recurrence and aggressive behavior, although they typically show morphologically benign features. In a tuberous sclerosis complex (TSC) patient, hamartomas can occur in multiple organs and cause diverse clinical symptoms. Cortical tubers, subependymal nodules (SENs) and subependymal giant cell astrocytomas (SEGAs) are representative lesions of TSC and can be detected by magnetic resonance imaging (MRI) of the brain.3 SEGA lesions have been found to occur in approximately 6.1% to 18.5% of TSC patients, and account for 90% of all intracranial tumors associated with TSC.4 SEGA lesions are commonly located in the foramen of Monro or the periventricular region,5 and can cause loss of vision, papillary edemas, intracranial calcification, and hydrocephalus.6 The primary method for treating SEGA lesions consists of surgical resection of the tumors; complete and early surgical removal of tumors has been shown to be the most important prognostic factor.6 Childhood CM has been shown to account for only ~0.5-1% of all meningiomas, with intraventricular occurrence of CM reported in only 27 children to date.2,7 Also, CM has not been reported in any TSC patients to date. Here we report a case of intraventricular CM, which appeared highly similar to SEGA in brain MRI scans, in a child with TSC.

Klüver–Bucy syndrome after unilateral frontotemporal resection in a child with tuberous sclerosis

Klüver-Bucy syndrome (KBS) is a behavioral phenotype that appears most often after bilateral temporal damage. The main features of KBS are compulsion to examine objects orally, increased sexual activity, placidity, hypermetamorphosis (irresistible impulse to notice and react to everything within sight), visual agnosia, and problems with memory. It is more rarely reported in children than in adults. We present a case of KBS in a 2-year-old boy with tuberous sclerosis complex (TSC) after left frontotemporal resection for refractory epilepsy. This is the first KBS after unilateral temporal resection in a child, although it has already been reported in two adult cases. It also is the first case reported in a TSC patient.

Abstract 5510: Tranilast inhibits growth of skin tumor cells in a xenograft mouse model of tuberous sclerosis complex.

Abstract Pharmacological approaches for treating tumors in patients with tuberous sclerosis complex (TSC) are inadequate. Although mTORC1 inhibitors such as rapamycin represent a major new avenue for treatment, we and others have shown that rapamycin improves but does not eradicate TSC skin tumors. We tested the effects of tranilast, an antiallergic and antifibrotic drug with antiproliferative effects, on fibroblasts grown from angiofibromas, forehead plaques, periungual fibromas, and normal-appearing skin from 5 patients with TSC. Tumor cells showed loss of TSC2 expression and hyperactivation of the mTORC1 signaling pathway. Tranilast (5, 10, 20, 40 μM) inhibited the viability of TSC skin tumor cells from five patients in an MTT assay. These effects on cell viability appeared to be independent of mTORC1 activity, since tranilast did not inhibit phosphorylation of ribosomal protein S6. Four paired samples of RNA from tumor and normal cells, treated with or without tranilast, were studied using gene expression arrays, revealing that tranilast significantly altered the expression of at least 36 genes, of which 12 are involved in transcription. In a xenograft model in which dermal-epidermal constructs comprising normal human keratinocytes with either TSC angiofibroma cells or TSC normal fibroblasts from a TSC patient were grafted to nude mice (6-8 mice per group), tranilast treatment (300 mg/kg/day) reduced the number of skin tumor cells compared to vehicle control group (P&amp;lt; 0.05). Tranilast treatment did not block angiogenesis or lymphangiogenesis in the xenograft model. These results indicate that tranilast has antiproliferative effects independent of mTORC1 and suggest that tranilast may be useful as an adjunctive agent for the treatment of TSC skin tumors. Citation Format: Shaowei Li, Ji-an Wang, Rajesh L. Thangapazham, Peter Klover, Joel Moss, Thomas N. Darling. Tranilast inhibits growth of skin tumor cells in a xenograft mouse model of tuberous sclerosis complex. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5510. doi:10.1158/1538-7445.AM2013-5510

Prevalence of angiomyolipoma among patients with tuberous sclerosis complex: A U.S. Healthcare Claims Database study.

e12042 Background: Angiomyolipoma (AML) are common benign neoplasm in the kidney, and are associated with tuberous sclerosis complex (TSC). The objectives of this study were to examine AML prevalence among TSC patients in a real world setting, and to explore the relationship between AML prevalence and ages, genders, or residential regions. Methods: A retrospective cohort study was conducted based on a large US commercial healthcare claims database. Patients with a TSC claim between 2000 and 2009 and with continuous 12-month enrollment after their first TSC claim were selected for the study. AML patients were identified based on ICD-9CM code (223.0X). Patients’ genders, residential regions, and age on their first TSC/or AML claim (if they had AML) were derived respectively from enrollment files and healthcare claims. Two-sample t tests and Chi-square tests were used to explore the relationships between AML prevalence, genders, residential regions and the age groups. Results: The study included 2,767 TSC patients with a mean age of 28.5 years on their first TSC claims, and 55.3% were female. AML prevalence among TSC patients was 7.8% in their first observed post-TSC year, and could be 78% at the end of the 10th observed post-TSC year if AML incidence rate (701.1 per 10,000 TSC patient years) remains constant. Associations between AML prevalence and age groups, genders, or residential regions were statistically significant (all p&lt;0.05); and variations of AML prevalence by genders (Male: 5.6 vs. Female: 9.7%), residential regions (6.2-9.4%) and age groups at the first TSC claim (3.9% for age&lt;1 year, 5.2% for age 1-5 years, 10.6% for 6-10 years, 8.4% for age 11-18 years, 13.6% for age 19-25 years, and 6.9% for age 26 years or more) were observed. Conclusions: In a real world setting AML occurred in 7.8% TSC patients in the first post-TSC year, and could increase to 78% within 10 years if the incidence rate remained at 701.1 per 10,000 TSC patient years. AML prevalence was associated with age, gender and residential regions, and varied significantly by ages, genders and residential regions. Further research is needed to explore the factors that resulted into these associations.

Abstract 2469: Increased cathepsin B expression in cultured tuberous sclerosis skin tumor cells and patient tumor tissues

Abstract Skin hamartomas in tuberous sclerosis complex (TSC) are disfiguring red tumors that contain fibroblast-like cells, vessels, fibrous tissue, and elongated hair follicles. Our recent studies show that TSC skin tumor cells induce angiogenesis and hair follicle neogenesis in a xenograft mouse model. These morphogenic changes are likely caused by altered expression of proteins involved in tissue remodeling. To identify such factors, we carried out 2-D gel analysis of cell extracts of TSC2-null fibroblasts derived from a TSC periungual fibroma (PF) compared to fibroblasts from patient normal-appearing skin (NL). PF cells had greater levels of all three forms of cathepsin B than TSC normal fibroblasts. Cathepsin B, a member of the lysosomal cysteine proteases family that has been implicated in angiogenesis and extracellular matrix remodeling, exists in pro-, single chain and double chain forms, and these were increased in PF cells by 1.6-, 2.3- and 8.3-fold, respectively. Western blot analysis of TSC skin tumor fibroblasts from 5 patients showed dramatically greater levels of active cathepsin B than in paired patient NL fibroblasts. Tumor cells from PFs showed greater intracellular cathepsin B enzyme activity than NL controls. Western blot and ELISA analysis showed that media conditioned by TSC skin tumor cells from 5 different patients contained 4.1- to 36-fold more procathepsin B than media conditioned by NL fibroblasts. Immunohistochemical staining of TSC patient angiofibromas and PFs showed greater numbers of cathepsin B-positive cells than patient normal-appearing skin. These results suggest that TSC skin tumor cells may induce hamartoma morphogenesis through expressing and releasing high level of cathepsin B. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2469. doi:1538-7445.AM2012-2469

Rapamycin as a Therapy of Choice After Renal Transplantation in a Patient With Tuberous Sclerosis Complex

Herein we have reported the use of rapamycin in immunosuppressive treatment after renal transplantation as a therapy of choice in a patient with diagnosis of tuberous sclerosis complex (TSC). TSC is a genetic disorder, caused by mutations of TSC1 or TSC2 genes. Products of these genes, hamartin and tuberin, create a complex that inhibits mammalian target of rapamycin (mTOR), a key protein engaged in regulation of the cell cycle. Mutations of TSC genes lead to constitutive activation of mTOR resulting in uncontrolled proliferation, differentiation, and migration of cells. As a consequence malformations of many organs arise. We have presented a case of a 47-year-old female TSC patient with multisystem involvement (skin, brain, lungs, and kidneys), who developed end-stage renal disease ESRD due to angiomyolipomas with subsequent bilateral nephrectomy. At the age of 44 years, she started hemodialysis treatments and 10 months later underwent kidney transplantation. Immunosuppressive treatment included the mTOR inhibitor rapamycin. Since the patient was discharged from hospital, she has remained in good clinical condition with stable graft function. Clinical evaluation after 2 years treatment with rapamycin revealed significant regression of skin lesions. Brain, chest, and abdominal cavity computed tomography images remained stable. No complications of immunosuppressive treatment or TSC were observed. Experimental and clinical studies have confirmed that rapamycin exerts beneficial effects in TSC, providing a new therapeutic option. Therefore an immunosuppressive regimen with rapamycin should be considered as the treatment of choice after kidney transplantation among patients with TSC seeking to avoid development or progression of disease complications.