scholarly journals MODL-27. MEK INHIBITION WITH TRAMETINIB SLOWS PROGRESSION OF MEDULLOBLASTOMA AND ATYPICAL TERATOID RHABDOID TUMOR IN ORTHOTOPIC XENOGRAFT MURINE MODEL

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii416-iii416
Author(s):  
Sujata Mushrif ◽  
Long Hung ◽  
Sakunthala Muthugounder ◽  
Shahab Asgharzadeh
Keyword(s):  
Cell Lines ◽  
Murine Model ◽  
Mapk Pathway ◽  
Autologous Transplantation ◽  
Rhabdoid Tumor ◽  
Clinical Samples ◽  
Atypical Teratoid Rhabdoid Tumor ◽  
Cell Viability Assay ◽  
Murine Tumors ◽  
Atypical Teratoid

Abstract BACKGROUND Combination of surgery, chemotherapy, autologous transplantation, irradiation constitutes treatment of CNS embryonal-cell tumors (Medulloblastoma-MBL, atypical teratoid rhabdoid tumor-AT/RT). Targeted agents to improve survival and decrease side effects are necessary. We hypothesize that inhibiting MAPK pathway in MBL and AT/RT may be beneficial. METHODS IHC(pERK) was performed on clinical tumors. Trametinib(MEK inhibitor) was tested on MBL(UW228, D283, DAOY); AT/RT(CHLA06, BT12) cell-lines. Luminescent cell-viability assay was done(72 hrs) and with crystal violet assay(10 days). Orthotopic, xenografts of MBL and AT/RT were made in NOD-Scid gamma mice. Mice were given Trametinib daily by gavage for 6 weeks(0.6mg/kg b.w). Western blot was performed on protein from cell lines and tumor xenografts incubated with Trametinib. H&E staining was done on murine tumors. RESULTS AT/RT(48%) and MBL(57%); Anaplastic(50%), Desmoplastic(40%), Classic(38%); Group 4(66%), Group 3(20%), SHH(55%), WNT(0%) showed presence of pERK(clinical samples). In-vitro, Trametinib completely abrogated the phosphorylation of ERK at 125nM in AT/RT and 50nM in MBL. The IC50 after 10 days exposure was 10nM for AT/RT and 35nM for MBL. Trametinib treated mice showed delay in tumor growth and significant survival advantage in both AT/RT (p=0.00336) and MBL (p=0.0069). Murine tumors showed decreased proliferation (H&E). CONCLUSION Trametinib decreased cell proliferation, increased survival in our murine model in both MBL and AT/RT. Pre-clinical results indicate benefits in subgroups of AT/RT and MBL with active MAPK pathway.

CSIG-24. TARGETED INHIBITION OF CDK5-MEDIATED REGULATION OF HUMAN ENDOGENOUS RETROVIRUS K (HML-2) ENVELOPE PROTEIN IN ATYPICAL TERATOID RHABDOID TUMOR

2021 ◽  
Vol 23 (Supplement_6) ◽  
pp. vi38-vi38
Author(s):  
Tara Doucet-O'Hare ◽  
Jared Rosenblum ◽  
Brianna DiSanza ◽  
Catherine DeMarino ◽  
Abigail Atkinson ◽  
...  
Keyword(s):  
Cell Viability ◽  
Cell Lines ◽  
Envelope Protein ◽  
Phosphorylation Site ◽  
Endogenous Retrovirus ◽  
Rhabdoid Tumor ◽  
Human Endogenous Retrovirus ◽  
Atypical Teratoid Rhabdoid Tumor ◽  
Atypical Teratoid ◽  
Targeted Inhibition

Abstract Atypical teratoid rhabdoid tumor (ATRT) is a pediatric brain tumor with a high mortality rate characterized by mutations in/ deletions of SWI/SNF matrix-associated actin-dependent regulator of chromatin sub-family B member 1 (SMARCB1). We previously showed that loss of SMARCB1 causes up-regulation and release of HML-2 subfamily of human endogenous retrovirus K envelope protein (HML-2 ENV), resulting in maintenance of pluripotency. Here, we investigated intracellular trafficking and release of HML-2 ENV. Further, we demonstrate two potential therapeutic strategies to decrease intracellular HML-2 ENV: 1) inhibition of calcium influx by ouabain, a cardiac glycoside toxic to neural stem cells, and 2) targeted inhibition of cyclin-dependent kinase 5 (CDK5), which is restricted to neurons by p35, its activator protein, by TP5. ATRT cell lines and tumor tissue obtained from patients were confirmed for SMARCB1 loss and increased HML-2 ENV. Cell viability and intracellular HML-2 ENV concentration were measured after treatment with ouabain and TP5 (CDK5 antagonist). We evaluated the calcium-mediated effect of ouabain on HML-2 intracellular concentration by treating the cells with ouabain, the calcium chelators calcimycin and EGTA, and calpeptin, a calpain inhibitor, which activates CDK5, and measuring HML-2 ENV and p35. We evaluated HML-2 ENV for a CDK5 consensus phosphorylation site and performed co-immunoprecipitation to evaluate direct interaction. We evaluated activity of CDK5 in ATRT cell lines by autoradiography. Both Ouabain and TP5 caused a decrease in cell viability in a dose-dependent manner. Further, ouabain treatment decreased HML-2 ENV intracellular concentration. We found that HML-2 ENV contains a consensus phosphorylation site for CDK5. We discovered that HML-2 ENV was bound to CDK5. We established that ATRT cell lines had hyperactive CDK5. Finally, we established that the effect of ouabain on HML-2 ENV was due to indirect inhibition of calcium-mediated activation of calpain and thus CDK5.

scholarly journals ATRT-07. DEFINING LOST AND GAINED TRANSCRIPTIONAL REGULATORY NETWORKS IN ATYPICAL TERATOID RHABDOID TUMOR

2021 ◽  
Vol 23 (Supplement_1) ◽  
pp. i2-i2
Author(s):  
Cody Nesvick ◽  
Liang Zhang ◽  
Alex Wixom ◽  
Feda Hamdan ◽  
Steven Johnsen ◽  
...  
Keyword(s):  
Cell Lines ◽  
Regulatory Networks ◽  
Regulatory Elements ◽  
Rhabdoid Tumor ◽  
Allelic Loss ◽  
Global Changes ◽  
Atypical Teratoid Rhabdoid Tumor ◽  
Transcriptional Regulatory Networks ◽  
Transcriptional Regulatory ◽  
Atypical Teratoid

Abstract Atypical teratoid rhabdoid tumor (ATRT) is a central nervous system cancer of infancy and early childhood that may occur anywhere along the neuraxis and is associated with a high rate of mortality. While contemporary multimodal therapeutic approaches have significantly improved overall survival, targeted therapy remains elusive, and treatment is often associated with significant morbidity. ATRT is unique in its genomic stability, with the only recurrent genetic abnormality being bi-allelic loss of the SMARCB1 gene, which encodes a core subunit of the BAF chromatin remodeling complex. The epigenetic mechanisms by which SMARCB1 loss leads to tumorigenesis are not yet well-defined and addressing this gap in understanding is necessary for creating efficacious, targeted therapeutics. To better understand the epigenetic features gained and lost in ATRT, we re-expressed SMARCB1 in a library of patient-derived and established ATRT cell lines of multiple molecular subtypes. SMARCB1 restoration significantly reduced or eliminated the proliferative and clonogenic capacity of each cell line. We performed assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-Seq) and RNA sequencing (RNA-Seq) to define putative transcriptional regulatory networks that are gained and lost in ATRT. SMARCB1 restoration was associated with global changes in chromatin openness consistent with the creation of new regulatory elements throughout the genome, and these were associated with induction of a diverse developmental transcriptional signature. Motif enrichment analysis of regions with increased accessibility defined a small but consistent number of centrally enriched transcription factor motifs across cell lines indicative of putative pioneer factors whose functions may be lost in ATRT. Pertinent chromatin immunoprecipitation with sequencing (ChIP-Seq) data will be discussed in the context of lost and gained transcriptional regulatory networks in ATRT and normal cellular development.

scholarly journals ATRT-03. IDENTIFICATION OF microRNA-BASED PROGNOSTIC BIOMARKERS AND CANDIDATE THERAPEUTIC AGENTS FOR ATYPICAL TERATOID/RHABDOID TUMOR

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii275-iii276
Author(s):  
Yang Zhang ◽  
Jianguo Xu
Keyword(s):  
Target Genes ◽  
Kinase Inhibitor ◽  
Therapeutic Agents ◽  
Rhabdoid Tumor ◽  
Janus Kinase ◽  
Prognostic Biomarkers ◽  
Atypical Teratoid Rhabdoid Tumor ◽  
Overlapping Genes ◽  
Hub Genes ◽  
Atypical Teratoid

Abstract BACKGROUND MicroRNA (miRNA) has been found to be involved in development of many malignant pediatric brain tumors, including atypical teratoid/rhabdoid tumor (AT/RT) that is highly aggressive and carries a dismal prognosis. The current study investigated the potential value of miRNAs and pivotal genes associated with AT/RT using bioinformatics analysis, aiming to identify new prognostic biomarkers and candidate drugs for AT/RT patients. METHODS Differentially expressed miRNAs (DEMs) and genes (DEGs) between AT/RT and normal control samples were obtained from GEO database. The target genes of DEMs were predicted via TargetScanHuman7.2 and miRDB, and then intersected with DEGs. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses of overlapping genes were conducted, followed by construction of protein-protein interaction network. Hub genes were determined by Cytoscape software, and their prognostic values were evaluated using Kaplan-Meier analysis. Connectivity Map database was used to identify latent therapeutic agents. RESULTS A total of 11 DEMs (hsa-miR-1224-5p, hsa-miR-128-3p, hsa-miR-17-5p, hsa-miR-18b-5p, hsa-miR-29c-5p, hsa-miR-329-3p, hsa-miR-379-5p, hsa-miR-433-3p, hsa-miR-488-5p, hsa-miR-656-3p and hsa-miR-885-5p) were screened. By intersecting 3275 predicted target genes and 925 DEGs, we finally identified 226 overlapping genes that were enriched in pathways in cancer and MAPK signaling pathway. Four hub genes (GRIA2, NRXN1, SLC6A1 and SYT1) were significantly associated with the overall survival of AT/RT patients. Candidate drugs included histone deacetylase inhibitor (givinostat), DNA synthesis inhibitor (floxuridine), cyclin-dependent kinase inhibitor (purvalanol) and janus kinase inhibitor (lestaurtinib). CONCLUSION In summary, this study systematically analyzed AT/RT-related miRNAs and pivotal genes to provide novel prognostic biomarkers and potential therapeutic agents.

Atypical Teratoid Rhabdoid Tumor in a Newborn: Can IVF Be a Risk Factor?

2021 ◽  
pp. 1-5
Author(s):  
Turkay Rzayev ◽  
Kubra Gokce ◽  
Safak Gucyetmez ◽  
Suheyla Bozkurt ◽  
Adnan Dagcinar ◽  
...  
Keyword(s):  
Risk Factor ◽  
Rhabdoid Tumor ◽  
Atypical Teratoid Rhabdoid Tumor ◽  
Atypical Teratoid

Epithelioid Sarcoma Arising in a Long-Term Survivor of an Atypical Teratoid/Rhabdoid Tumor in a Patient With Rhabdoid Tumor Predisposition Syndrome

2021 ◽  
pp. 109352662098649
Author(s):  
Tiffany G Baker ◽  
Michael J Lyons ◽  
Lee Leddy ◽  
David M Parham ◽  
Cynthia T Welsh
Keyword(s):  
Epithelioid Sarcoma ◽  
Rhabdoid Tumor ◽  
Malignant Rhabdoid Tumor ◽  
Atypical Teratoid Rhabdoid Tumor ◽  
Diagnostic Challenge ◽  
Patient Demographics ◽  
Immunohistochemical Markers ◽  
Genetic Aberration ◽  
Atypical Teratoid ◽  
Rhabdoid Tumors

Rhabdoid tumor predisposition syndrome (RTPS) is defined as the presence of a SMARCB1 or SMARCA4 genetic aberration in a patient with malignant rhabdoid tumor. Patients with RTPS are more likely to present with synchronous or metachronous rhabdoid tumors. Based on the current state of rhabdoid tumor taxonomy, these diagnoses are based largely on patient demographics, anatomic location of disease, and immunohistochemistry, despite their nearly identical histologic and immunohistochemical profiles. Thus, the true distinction between such tumors remains a diagnostic challenge. Central nervous system atypical teratoid/rhabdoid tumor (AT/RT) is a rare, aggressive, primarily pediatric malignancy with variable histologic features and a well documented association with loss of SMARCB1 expression. Epithelioid sarcoma (ES) is a rare soft tissue tumor arising in patients of all ages and characteristically staining for both mesenchymal and epithelial immunohistochemical markers while usually demonstrating loss of SMARCB1 expression. To our knowledge we herein present the first documented case of a patient with RTPS who presented with metachronous AT/RT and ES.

scholarly journals ATRT-04. INHERITED RHABDOID PREDISPOSITION SYNDROME: A CASE OF CHOROID PLEXUS CARCINOMA AND ATYPICAL TERATOID RHABDOID TUMOR IN SIBLINGS

2020 ◽  
Vol 22 (Supplement_3) ◽  
pp. iii276-iii276
Author(s):  
Alexis Judd ◽  
Erin Wright ◽  
Sarah Rush
Keyword(s):  
Overall Survival ◽  
Choroid Plexus ◽  
Disease Recurrence ◽  
Genetic Alterations ◽  
Rhabdoid Tumor ◽  
Choroid Plexus Carcinoma ◽  
High Dose ◽  
Atypical Teratoid Rhabdoid Tumor ◽  
Increased Risk ◽  
Atypical Teratoid

Abstract Choroid plexus carcinoma (CPC) and Atypical teratoid/rhabdoid tumor (ATRT) are aggressive, malignant brain cancers most commonly arising in children less than 3 years of age. These tumors often have genetic alterations in the tumor suppressor gene SMARCB1/INI1. Rhabdoid predisposition syndrome (RTPS) categorizes patients with germline mutations in SMARCB1 or SMARCA4, leading to a markedly increased risk of developing rhabdoid tumors. Both CPC and ATRT have been demonstrated in patients with these rhabdoid predisposition syndromes. In general, these tumors tend to have a poor prognosis. However, with the presence of a SMARCB1 mutation they may have improved overall survival. We present two interesting cases of siblings with maternally inherited SMARCB1 mutations: one a 21-month-old male who presented with an ATRT and another a 10 month old female who presented with a CPC. The ATRT was treated as per the Children’s Oncology Group study ACNS0333 with high dose chemotherapy and stem cell rescue as well as cranial radiation. The CPC was treated as per CPT-SIOP 2009 with etoposide, cyclophosphamide and vincristine. Unlike other patients with these aggressive tumors, both of these patients are alive without evidence of disease recurrence 8 and 7 years post therapy, respectively. Additional genomic testing on both tumors is currently pending in order to potentially identify other mutations that may impact survival. These cases further illustrate the similar profile of two very different tumors with improved overall survival that may be secondary to mutations in SMARCB1 in RTPS.

Atypical teratoid/rhabdoid tumor in adult: case series and an integrated survival analysis

2021 ◽  
pp. 1-16
Author(s):  
Ai Jun Peng ◽  
Shu Cai Fan ◽  
Ya Xing Chen ◽  
Jian Han Huang ◽  
Yi Cao ◽  
...  
Keyword(s):  
Survival Analysis ◽  
Case Series ◽  
Rhabdoid Tumor ◽  
Atypical Teratoid Rhabdoid Tumor ◽  
Adult Case ◽  
Atypical Teratoid
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