Publications by authors named "Giannikou K"

Article Synopsis
  • - The study analyzed genomic and transcriptomic data from 138 germ cell tumors to find out why some tumors resist treatment with cisplatin, a common chemotherapy drug.
  • - They focused on specific genetic mutations (like KRAS, TP53, and KIT) and patterns in gene copies that might contribute to this resistance, observing that certain mutations were more common in primary tumors compared to metastatic ones.
  • - The research found that tumors with platinum-resistant alterations had lower transcriptomic scores linked to sensitivity to cisplatin, indicating a possible connection between these genetic changes and treatment resistance.
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Aims: Although TSC1 or TSC2 inactivating mutations that lead to mTORC1 hyperactivation have been reported in hepatic angiomyolipomas (hAML), the role of other somatic genetic events that may contribute to hAML development is unknown. There are also limited data regarding the tumour microenvironment (TME) of hAML. The aim of the present study was to identify other somatic events in genomic level and changes in TME that contribute to tumorigenesis in hAML.

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Tuberous sclerosis complex (TSC) is a neurogenetic disorder due to loss-of-function TSC1 or TSC2 variants, characterized by tumors affecting multiple organs, including skin, brain, heart, lung, and kidney. Mosaicism for TSC1 or TSC2 variants occurs in 10%-15% of individuals diagnosed with TSC. Here, we report comprehensive characterization of TSC mosaicism by using massively parallel sequencing (MPS) of 330 TSC samples from a variety of tissues and fluids from a cohort of 95 individuals with mosaic TSC.

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Background: We aim to implement an immune cell score model in routine clinical practice for resected non-small-cell lung cancer (NSCLC) patients (NCT03299478). Molecular and genomic features associated with immune phenotypes in NSCLC have not been explored in detail.

Patients And Methods: We developed a machine learning (ML)-based model to classify tumors into one of three categories: inflamed, altered, and desert, based on the spatial distribution of CD8+ T cells in two prospective (n = 453; TNM-I trial) and retrospective (n = 481) stage I-IIIA NSCLC surgical cohorts.

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Tuberous Sclerosis Complex (TSC) is caused by loss of function variants in either and is characterized by broad phenotypic heterogeneity Currently, there is limited knowledge regarding the role of the mitochondrial genome (mtDNA) in TSC pathogenesis. In this study, we aimed to determine the prevalence and spectrum of germline and somatic mtDNA variants in TSC and identify potential disease modifiers. Analysis of mtDNA amplicon massively parallel sequencing (aMPS) data, off-target mtDNA from whole-exome sequencing (WES), and/or qPCR, revealed mtDNA alterations in 270 diverse tissues (139 TSC-associated tumors and 131 normal tissue samples) from 199 patients and six healthy individuals.

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A mosaic state arises when pathogenic variants are acquired in certain cell lineages during postzygotic development, and mosaic individuals may present with a generalized or localized phenotype. Here, we review the current state of knowledge regarding mosaicism for eight common tumor suppressor genes-, , , , , , , and -and their related genetic syndromes/entities. We compare and discuss approaches for comprehensive diagnostic genetic testing, the spectrum of variant allele frequency, and disease severity.

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BackgroundTuberous sclerosis complex (TSC) is a neurogenetic syndrome due to loss-of-function mutations in TSC2 or TSC1, characterized by tumors at multiple body sites, including facial angiofibroma (FAF). Here, an ultrasensitive assessment of the extent and range of UV-induced mutations in TSC facial skin was performed.MethodsA multiplex high-sensitivity PCR assay (MHPA) was developed, enabling mutation detection at extremely low (<0.

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Introduction: Lymphangioleiomyomatosis (LAM) is a rare low-grade metastasising disease characterised by cystic lung destruction. The genetic basis of LAM remains incompletely determined, and the disease cell-of-origin is uncertain. We analysed the possibility of a shared genetic basis between LAM and cancer, and LAM and pulmonary function.

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Epigenetic modifications are considered of utmost significance for tumor ontogenesis and progression. Especially, it has been found that miRNA expression, as well as DNA methylation plays a significant role in central nervous system tumors during childhood. A total of 49 resected brain tumors from children were used for further analysis.

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The lack of animal models for some human diseases precludes our understanding of disease mechanisms and our ability to test prospective therapies in vivo. Generation of kidney organoids from Tuberous Sclerosis Complex (TSC) patient-derived-hiPSCs allows us to recapitulate a rare kidney tumor called angiomyolipoma (AML). Organoids derived from TSC2 hiPSCs but not from isogenic TSC2 or TSC2 hiPSCs share a common transcriptional signature and a myomelanocytic cell phenotype with kidney AMLs, and develop epithelial cysts, replicating two major TSC-associated kidney lesions driven by genetic mechanisms that cannot be consistently recapitulated with transgenic mice.

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Purpose: This was a multicenter, histology-agnostic, single-arm prospective phase II trial of therapeutic activity of everolimus, an oral mTORC1 inhibitor, in patients with advanced solid tumors that harbored / or mutations.

Patients And Methods: Patients with tumors with inactivating / or activating mutations identified in any Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory were eligible. Patients were treated with everolimus 10 mg once daily until disease progression or unacceptable toxicity.

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Lymphangioleiomyomatosis is a rare destructive lung disease affecting primarily women and is the primary lung manifestation of tuberous sclerosis complex (TSC). In lymphangioleiomyomatosis, biallelic loss of TSC1/2 leads to hyperactivation of mTORC1 and inhibition of autophagy. To determine how the metabolic vulnerabilities of TSC2-deficient cells can be targeted, we performed a high-throughput screen utilizing the "Repurposing" library at the Broad Institute of MIT and Harvard (Cambridge, MA), with or without the autophagy inhibitor chloroquine.

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Tuberous sclerosis complex (TSC) is an autosomal dominant tumor suppressor syndrome, characterized by tumor development in multiple organs, including renal angiomyolipoma. Biallelic loss of TSC1 or TSC2 is a known genetic driver of angiomyolipoma development, however, whether an altered transcriptional repertoire contributes to TSC-associated tumorigenesis is unknown. RNA-seq analyses showed that MITF A isoform (MITF-A) was consistently highly expressed in angiomyolipoma, immunohistochemistry showed microphthalmia-associated transcription factor nuclear localization, and Chromatin immuno-Precipitation Sequencing analysis showed that the MITF-A transcriptional start site was highly enriched with H3K27ac marks.

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Subependymal giant-cell astrocytomas (SEGAs) are slow-growing brain tumors that are a hallmark feature seen in 5-10% of patients with Tuberous Sclerosis Complex (TSC). Though histologically benign, they can cause serious neurologic symptoms, leading to death if untreated. SEGAs consistently show biallelic loss of TSC1 or TSC2.

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Lymphangioleiomyomatosis (LAM) is a metastatic neoplasm of reproductive-age women associated with mutations in tuberous sclerosis complex genes. LAM causes cystic remodeling of the lung and progressive respiratory failure. The sources and cellular characteristics of LAM cells underlying disease pathogenesis remain elusive.

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Tuberous sclerosis complex (TSC) is characterized by tumor development in the brain, heart, kidney, and lungs. In TSC tumors, loss of the TSC1/TSC2 protein complex leads to activation of mTORC1 with downstream effects on anabolism and cell growth. Because mTORC1 activation enhances mRNA transcription, we hypothesized that aberrant mTORC1 activation might confer TSC-null cell dependence on transcriptional regulation.

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Purpose: To examine the prevalence and spectrum of mosaic variant allele frequency (MVAF) in tuberous sclerosis complex (TSC) patients with low-level mosaicism and correlate genetic findings with clinical features and transmission risk.

Methods: Massively parallel sequencing was performed on 39 mosaic TSC patients with 170 different tissue samples.

Results: TSC mosaic patients (MVAF: 0-10%, median 1.

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Introduction: Lymphangioleiomyomatosis (LAM) occurs either associated with tuberous sclerosis complex (TSC) or as sporadic disease (S-LAM). Risk factors for development of S-LAM are unknown. We hypothesised that DNA sequence variants outside of / might be associated with susceptibility for S-LAM and performed a genome-wide association study (GWAS).

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Perivascular epithelioid cell tumors (PEComas) are a family of mesenchymal neoplasms that have smooth muscle and melanocytic differentiation. They can be sporadic or associated with tuberous sclerosis complex and commonly present in the kidney as angiomyolipoma or in the lung as pulmonary clear cell sugar tumors or lymphangioleiomyomatosis. However, they can present at any visceral or soft tissue site.

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Subependymal giant cell astrocytomas (SEGAs) are rare, low-grade glioneuronal brain tumors that occur almost exclusively in patients with tuberous sclerosis complex (TSC). Though histologically benign, SEGAs can lead to serious neurological complications, including hydrocephalus, intractable seizures and death. Previous studies in a limited number of SEGAs have provided evidence for a biallelic two-hit inactivation of either , resulting in constitutive activation of the mechanistic target of rapamycin complex 1 pathway.

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Differentiation abnormalities are a hallmark of tuberous sclerosis complex (TSC) manifestations; however, the genesis of these abnormalities remains unclear. Here we report on mechanisms controlling the multi-lineage, early neuronal progenitor and neural stem-like cell characteristics of lymphangioleiomyomatosis (LAM) and angiomyolipoma cells. These mechanisms include the activation of a previously unreported Rheb-Notch-Rheb regulatory loop, in which the cyclic binding of Notch1 to the Notch-responsive elements (NREs) on the Rheb promoter is a key event.

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Article Synopsis
  • Lymphangioleiomyomatosis (LAM) is a progressive lung disease linked to mutations in tumor suppressor genes, and creating accurate models to study it has been difficult.
  • Researchers created a human cell model of LAM by turning patient fibroblasts with tuberous sclerosis complex and LAM into induced pluripotent stem cells, which they then differentiated to reflect lung tumor cells.
  • The resulting cell lines showed key characteristics of LAM, such as hyperactive mTORC1 signaling and specific molecular markers, suggesting that the genetic mutation contributes to the disease and that these models can help in understanding LAM and developing treatments.
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BackroundMicrocephaly can either be isolated or it may coexist with other neurological entities and/or multiple congenital anomalies, known as syndromic microcephaly. Although many syndromic cases can be classified based on the characteristic phenotype, some others remain uncertain and require further investigation. The present study describes the application of array-comparative genomic hybridization (array-CGH) as a diagnostic tool for the study of patients with clinically unknown syndromic microcephaly.

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