Project description:PurposeWe explored the use of intraventricular 131I-Omburtamab targeting B7-H3 in patients with ETMR.MethodsPatients were enrolled in an IRB approved, phase 1, 3 + 3 dose escalation trial. Patients with CNS disease expressing the antibody target antigen B7-H3 were eligible. We report on a cohort of three patients with ETMR who were enrolled on the study. Three symptomatic children (ages 14 months, 3 and 3.5 years) had large parietal masses confirmed to be B7-H3-reactive ETMR. Patients received 2 mCi 131I-Omburtamab as a tracer followed by one or two therapeutic 131I-Omburtamab injections. Dosimetry was based on serial CSF, blood samplings and region of interest (ROI) on nuclear scans. Brain and spine MRIs and CSF cytology were done at baseline, 5 weeks after 131I-Omburtamab, and approximately every 3 months thereafter. Acute toxicities and survival were noted.ResultsPatients received surgery, focal radiation, and high dose chemotherapy. Patients 1 and 2 received 131I-Omburtamab (80 and 53 mCi, respectively). Patient 3 had a local recurrence prior to 131I-Omburtamab treated with surgery, external beam radiation, chemotherapy, then 131I-Omburtamab (36 mCi). 131I-Omburtamab was well-tolerated. Mean dose delivered by 131I-Omburtamab was 68.4 cGy/mCi to CSF and 1.95 cGy/mCi to blood. Mean ROI doses were 230.4 (ventricular) and 58.2 (spinal) cGy/mCi. Patients 1 and 2 remain in remission 6.8 years and 2.3 years after diagnosis, respectively; patient 3 died of progressive disease 7 months after therapy (2 years after diagnosis).Conclusions131I-Omburtamab appears safe with favorable dosimetry therapeutic index. When used as consolidation following surgery and chemoradiation therapy, 131I-Omburtamab may have therapeutic benefit for patients with ETMR.
Project description:Embryonal tumor with multilayered rosettes (ETMR) is an aggressive and rare pediatric embryonal brain tumor. Amplification of C19MC microRNA cluster and expression of LIN28 are distinctive features of ETMR. Despite the increasing efforts to decipher ETMR, the biology remains poorly understood. To date, the role of aberrant alternative splicing in ETMR has not been thoroughly investigated. In the current study, a comprehensive analysis was performed on published unprocessed RNA-seq reads of tissue-matched ETMR and fetal controls datasets. Gene expression was quantified in samples using Kallisto/sleuth pipeline. For the alternative splicing analysis, STAR, SplAdder and rMATS were used. Functional enrichment analysis was subsequently performed using Metascape. The expression analysis identified a total of 3622 differentially expressed genes (DEGs) between ETMR and fetal controls while 1627 genes showed differential alternative splicing patterns. Interestingly, genes with significant alternative splicing events in ETMR were identified to be involved in signaling pathways such as ErbB, mTOR and MAPK pathways as well as ubiquitin-mediated proteolysis, cell cycle and autophagy. Moreover, up-regulated DEGs with alternative splicing events were involved in important biological processes including nuclear transport, regulation of cell cycle and regulation of Wnt signaling pathway. These findings highlight the role of aberrant alternative splicing in shaping the ETMR tumor landscape, and the identified pathways constitute potential therapeutic targets.
Project description:BackgroundEmbryonal tumor with multilayered rosettes (ETMR) is an aggressive central nervous system primitive neuroectodermal tumor (CNS-PNET) variant. ETMRs have distinctive histology, amplification of the chromosome 19 microRNA cluster (C19MC) at chr19q13.41-42, expression of the RNA binding protein Lin28, and dismal prognosis. Functional and therapeutic studies of ETMR have been limited by a lack of model systems.MethodsWe have established a first cell line, BT183, from a case of ETMR and characterized its molecular and cellular features. LIN28 knockdown was performed in BT183 to examine the potential role of Lin28 in regulating signaling pathway gene expression in ETMR. Cell line findings were corroborated with immunohistochemical studies in ETMR tissues. A drug screen of 73 compounds was performed to identify potential therapeutic targets.ResultsThe BT183 line maintains C19MC amplification, expresses C19MC-encoded microRNAs, and is tumor initiating. ETMRs, including BT183, have high LIN28 expression and low let-7 miRNA expression, and show evidence of mTOR pathway activation. LIN28 knockdown increases let-7 expression and decreases expression of IGF/PI3K/mTOR pathway components. Pharmacologic inhibition of the mTOR pathway reduces BT183 cell viability.ConclusionsBT183 retains key genetic and histologic features of ETMR. In ETMR, Lin28 is not only a diagnostic marker but also a regulator of genes involved in growth and metabolism. Our findings indicate that inhibitors of the IGF/PI3K/mTOR pathway may be promising novel therapies for these fatal embryonal tumors. As the first patient-derived cell line of these rare tumors, BT183 is an important, unique reagent for investigating ETMR biology and therapeutics.
Project description:Embryonal tumor with multilayered rosettes (ETMR) is a rare, aggressive embryonal central nervous system tumor characterized by LIN28A expression and alterations in the C19MC locus. ETMRs predominantly occur in young children, have a dismal prognosis, and no definitive treatment guidelines have been established. We report on nine consecutive patients and review the role of initiation/timing of radiotherapy on survival. Between 2006 and 2018, nine patients were diagnosed with ETMR. Diagnosis was confirmed histopathologically, immunohistochemically and molecularly. Median age was 25 months (5-38). Location was supratentorial in five, pineal in three, and brainstem in one. Seven patients had a gross total resection, one a partial resection and one a biopsy at initial diagnosis. Chemotherapy augmented with intrathecal therapy started a median of 10 days (7-20) after surgery. Only two patients who after gross total resection received radiotherapy very early on (six weeks after diagnosis) are alive and in complete remission 56 and 50 months after diagnosis. All remaining patients for whom radiotherapy was deferred until the end of chemotherapy recurred, albeit none with leptomeningeal disease. A literature research identified 228 patients with ETMR. Including our patients only 26 (11%) of 237 patients survived >36 months with no evidence of disease at last follow-up. All but two long-term (>36 months) survivors received radiotherapy, ten of whom early on following gross total resection (GTR). GTR followed by early focal radiotherapy and intrathecal therapy to prevent leptomeningeal disease are potentially important to improve survival of ETMR in the absence of effective targeted therapies.
Project description:Embryonal Tumors with Multilayered Rosettes (ETMRs) have recently been described as a new entity of rare pediatric brain tumors with fatal outcome. We show here that ETMRs are characterized by a parallel activation of Shh- and Wnt-signaling. Co-activation of these pathways in murine neural precursors is sufficient to induce ETMR-like tumors in vivo that resemble their human counterparts based on histology and global gene expression analyses, and point to apical radial glia cells as the possible tumor cell-of-origin. Overexpression of LIN28A, which is a hallmark of human ETMRs, augments Sonic Hedgehog (Shh)- and Wnt-signaling in these precursor cells through downregulation of let7-miRNA, and LIN28A/let7a interaction with the Shh-pathway was detected at the level of Gli mRNA. Finally, human ETMR cells that were transplanted into immunocompromised host mice were responsive to the Shh-inhibitor Arsenic trioxide (ATO). Our findings provide a novel mouse model to study this tumor type, demonstrate the driving role of Wnt- and Shh-activation in the growth of ETMRs and propose downstream inhibition of Shh-signaling as a therapeutic option for patients with ETMRs. Gene expression data of hGFAP-cre::Ctnnb1(ex3)Fl/+SmoM2Fl/+ , hGFAP-cre::SmoM2Fl/+ , hGFAP-cre::Ctnnb1(ex3)Fl/+ and Control mice
Project description:Embryonal tumors with multilayered rosettes (ETMR) are rare malignant embryonal brain tumors. The prognosis of ETMR is poor and novel therapeutic approaches are desperately needed. Comprehension of ETMR tumor biology is based on only few previous molecular studies, which mainly relied on the analyses of nucleic acids. In this study, we explored integrated ETMR proteomics with the aim to identify novel therapeutic vulnerabilities in these deadly tumors. Using mass spectrometry, proteome data were acquired from FFPE tissue of 40 embryonal brain tumors (16 ETMR, 9 atypical teratoid/rhabdoid tumors (AT/RT), 15 medulloblastomas (MB)) and integrated with case-matched global DNA methylation data, publicly available transcriptome data, and proteome data of further pediatric brain tumors. Proteome-based cluster analyses grouped ETMR samples according to histomorphology, separating neuropil-rich tumors with neuronal signatures from primitive tumors with signatures relating to stemness and chromosome organization. Microdissection analyses highlighted the close relationship of ETMR histomorphology and proteome profiles, regardless of intra- or intertumoral comparisons. Integrated proteomics showcased that ETMR harbor proteasome regulatory proteins in abundancy, implicating their strong dependency on the proteasome machinery to safeguard proteostasis. Respectively, in vitro cell culture viability assays using embryonal brain tumor cell lines BT183 (ETMR), BT16 (AT/RT), and D283 (MB) highlighted that ETMR cells were highly vulnerable towards treatment with the CNS penetrant proteasome inhibitor Marizomib. In summary, histomorphology stipulates the proteome signatures of ETMR. Pervasive and histomorphology-independent abundancy of proteasome regulatory proteins in ETMR indicates a strong proteasome dependency throughout these tumors. As validated in cell culture experiments, proteasome inhibition poses a promising therapeutic option in ETMR.
Project description:Adult cancers often arise from premalignant clonal expansions. Whether the same is true of childhood tumors has been unclear. To investigate whether Wilms tumor (nephroblastoma; a childhood kidney cancer) develops from a premalignant background, we examined the phylogenetic relationship between tumors and corresponding normal tissues. In 14 of 23 cases studied (61%), we found premalignant clonal expansions in morphologically normal kidney tissues that preceded tumor development. These clonal expansions were defined by somatic mutations shared between tumor and normal tissues but absent from blood cells. We also found hypermethylation of the H19 locus, a known driver of Wilms tumor development, in 58% of the expansions. Phylogenetic analyses of bilateral tumors indicated that clonal expansions can evolve before the divergence of left and right kidney primordia. These findings reveal embryonal precursors from which unilateral and multifocal cancers develop.
Project description:Upper tract urothelial carcinoma comprises 5-10% of all urothelial carcinoma cases. This disease tends to have a more aggressive course than its lower urinary tract counterpart, with 60% of patients presenting with invasive disease and 30% of patients presenting with metastatic disease at diagnosis. The diagnostic workup of UTUC involves imaging with CT urogram, urine cytology, and direct visualization and biopsy of suspected lesions via ureteroscopy. Standard treatment of high-grade UTUC involves radical nephroureterectomy (RNU) and excision of the ipsilateral bladder cuff. Both the NCCN and EAU Guidelines include neoadjuvant chemotherapy as a treatment option for select patients with UTUC; however, there are no strict guidelines. Much of the rationale for neoadjuvant chemotherapy is based on extrapolation from data from muscle-invasive bladder cancer, which has demonstrated a 5-year OS benefit of 5-8%. Retrospective studies evaluating the use of NACT in urothelial carcinoma have yielded pathologic objective response rates of 48% in UTUC cohorts. The randomized Phase III POUT study noted a DFS advantage with adjuvant platinum-based chemotherapy, compared with surveillance in UTUC, of 70% vs. 51% at 2 years. Though not the standard of care, multiple studies have explored the use of perioperative immunotherapy or chemoimmunotherapy in the management of invasive urothelial carcinoma. The PURE-02 study explored the use of neoadjuvant pembrolizumab in patients with high-risk UTUC. A small study of 10 patients, it showed no significant signals of activity with neoadjuvant pembrolizumab. Another Phase II study of neoadjuvant ipilimumab and nivolumab in cisplatin-ineligible UTUC yielded more promising findings, with 3/9 patients attaining a pathologic CR and the remaining six pathologically downstaged. The ABACUS trial found a 31% pathologic complete response rate amongst cisplatin-ineligible MIBC patients treated with neoadjuvant atezolizumab. The use of adjuvant immunotherapy has been explored over three phase III trials. The CheckMate-274 trial found a DFS benefit with the addition of one year of adjuvant nivolumab in patients with high-risk urothelial carcinoma. The IMvigor-010 study of adjuvant atezolizumab was a negative study. The AMBASSADOR trial of adjuvant pembrolizumab is pending results. With the FDA approval of erdafitinib in metastatic urothelial carcinoma, similar targets have been explored for use in perioperative use in invasive urothelial carcinoma, as with adjuvant infigratinib in the PROOF-302 trial. As the treatment paradigm for urothelial carcinoma evolves, further prospective studies are needed to expand the perioperative treatment landscape of UTUC.
Project description:Psoriasis is a chronic, common, inflammatory skin disease. The classic skin lesions can be described as sharply demarcated, scaly, erythematous plaques often found on the extensor surfaces. Several variants of psoriasis have also been described, including palmoplantar, pustular, erythrodermic, and guttate forms. Although psoriasis is usually diagnosed clinically, characteristic histologic findings include hyperkeratosis, parakeratosis, and acanthosis of the epidermis with dilated blood vessels and a lymphocytic infiltrate. Psoriasis is an immune-mediated disease, and although the etiology is not fully understood, genetic and environmental factors have been implicated. Importantly, psoriasis is associated with a number of systemic complications and comorbidities that have a high impact on affected patients.