Rhabdoid tumors (RTs) are aggressive tumors of early childhood that occur most often in brain (AT/RTs) or kidney (KRTs). Regardless of location, they are characterized by loss of functional SMARCB1 protein, a component of the SWI/SNF chromatin remodeling complex. The aim of this study was to determine genes and biological process dysregulated in common to both AT/RTs and KRTs. Gene expression for AT/RTs was compared to that of other brain tumors and normal brain using microarray data from our lab. Similar analysis was performed for KRTs and other kidney tumors and normal kidney using data from GEO. Dysregulated genes common to both analyses were analyzed for functional significance. Unsupervised hierarchical clustering of RTs identified 3 major subsets: 2 comprised of AT/RTs, and 1 of KRTs. Compared to other tumors, 1187, 663 and 539 genes were dysregulated in each subset, respectively. Only 14 dysregulated genes were common to all 3 subsets. Compared to normal tissue, 5209, 4275 and 2841 genes were dysregulated in each subset, with an overlap of 610 dysregulated genes. Among these genes, processes associated with cell proliferation, MYC activation, and epigenetic dysregulation were common to all 3 RT subsets. The low overlap of dysregulated genes in AT/RTs and KRTs suggests that factors in addition to SMARCB1 loss play a role in determining subsequent gene expression. Drugs which target cell cycle or epigenetic genes may be useful in all RTs. Additionally, targeted therapies tailored to specific RT subset molecular profiles should be considered.
Pediatric rhabdoid tumors of kidney and brain show many differences in gene expression but share dysregulation of cell cycle and epigenetic effector genes.
Specimen part
View SamplesThis SuperSeries is composed of the SubSeries listed below.
No associated publication
Specimen part, Treatment
View SamplesCongenital glioblastoma multiforme (cGBM) historically has been considered an aggressive tumor of infancy requiring extensive chemotherapy to achieve cure. We report on 4 patients at our institution with cGBMs who were treated with surgery and chemotherapy (carboplatin and etoposide every 21 days for 2-6 cycles). Four of four patients are progression free at a median time of 27.5 months (22-103 months). To characterize the molecular biology of cGBM, we compared the gene expression profiles of 3 cGBMs to 12 pediatric and 6 primary adult glioblastomas collected at our institution. Unsupervised hierarchical clustering showed cGBMs grouped together with other high-grade gliomas. cGBMs demonstrated marked similarity to both pediatric and adult GBMs, with only a total of 31 differentially expressed genes identified (FDR < 0.05). Unique molecular features of congenital GBMs identified included over-expression of multiple genes involved in glucose metabolism and tissue hypoxia pathways. Four tyrosine kinases were also mong the up-regulated genes (RET, RASGRF2, EFNA5, ALK). Thus, at our institution congenital GBMs, while similar both histologically and molecularly to other GBMs, appear to have a good prognosis with surgery in combination with relatively moderate chemotherapy. Further study is needed to determine if the few gene expression differences that were identified may contribute to the better survival seen in these tumors compared to pediatric or adult GBMs.
Clinical and molecular characteristics of congenital glioblastoma.
Sex, Disease, Disease stage
View SamplesMolecular profiling of tumors has proven a valuable tool for identification of prognostic and diagnostic subgroups in medulloblastomas, glioblastomas and other cancers. However, the molecular landscape of atypical teratoid / rhabdoid tumors (AT/RTs) remains largely unexplored. To address this issue, we used microarrays to measure the gene expression profiles of 18 AT/RTs, and performed unsupervised hierarchical clustering to determine molecularly similar subgroups. Four major subgroups (clusters) were identified. These did not conform to gender, tumor location, or presence of monosomy 22. Clusters showed distinct gene signatures and differences in enriched biological processes, including elevated expression of choroid plexus genes in Cluster 4. In addition, survival differed significantly by cluster, with shortest survival (mean 4.7 months) in both Clusters 3 and 4 compared to Clusters 1 and 2 (mean 28.1 months). Analysis showed that multiple bone morphogenetic protein (BMP) pathway genes were up-regulated in the short survival clusters, with BMP4 showing the most significant up-regulation (270-fold). Thus, high expression of BMP pathway genes was negatively associated with survival in this dataset. Our study indicates that molecular subgroups exist within AT/RTs, and that molecular profiling of these comparatively rare tumors may be of diagnostic, prognostic and therapeutic value.
High expression of BMP pathway genes distinguishes a subset of atypical teratoid/rhabdoid tumors associated with shorter survival.
Sex, Specimen part
View SamplesProgesterone receptors (PR) are co-expressed in over half of estrogen receptor (ER) positive breast cancers and predict positive response to endocrine therapy. PR can directly and globally modify ER action to attenuate tumor growth. However, whether this suppression occurs solely through PR-ER interactions remains unknown. We assessed tumor growth in two highly ER and PR positive breast cancer patient-derived xenografts (PDX) and found that natural and synthetic progestins potently antagonize the mitogenic effects of estrogens. Here we probed the genome-wide mechanisms by which this occurs. Chronic progestin treatment reversed expression of up to half of estrogen up- and downregulated genes at the transcript level. However, fewer than a quarter of ER DNA binding events were altered by progesterone. The PR cistrome showed an interesting bimodal distribution. In the first group, more than half of PR binding sites were co-occupied by ER, with a propensity for both receptors to coordinately gain or lose binding in the presence of progesterone. In the second group, PR, but not ER, was associated with a large fraction of RNA polymerase III (Pol III)-transcribed tRNA genes regardless of hormone treatment. Furthermore, PR formed a physical association with the Pol III holoenzyme. Select tRNAs with colocalization of PR and POLR3A at their promoters were reduced in tumors grown with estrogen plus progestin compared to estrogen alone. These data uncover a mechanism in solid tumors by which PR modulates the bioavailability of translational molecules that are necessary for robust tumor growth, which could indirectly impede ER action.
No associated publication
Specimen part, Treatment
View SamplesEwing Sarcoma is the second most common solid pediatric malignant neoplasm of the bone and soft tissue. Driven by EWS/Ets, or rarely variant, oncogenic fusions, Ewing Sarcoma is a biologically and clinically aggressive disease with a high propensity for metastasis. Our laboratory has previously identified the Jumonji-domain H3K9 me 1/2 histone demethylase KDM3A as a novel oncogene downstream of EWS/Fli1, the most common oncofusion in Ewing Sarcoma. Herein, we uncover a role for KDM3A in the promotion of Ewing Sarcoma metastasis.
The histone demethylase KDM3A, and its downstream target MCAM, promote Ewing Sarcoma cell migration and metastasis.
Cell line
View SamplesAtypical teratoid/rhabdoid tumor (ATRT) is a highly malignant CNS neoplasm whichprimarily occurs in children under three years of age. Due to poor outcomes with intense and toxicmultimodality treatment, new therapies are urgently needed. Histone deacetylase inhibitors (HDIs)have been evaluated as novel agents for multiple malignancies and have been shown to function asradiosensitizers. They act as epigenetic modifiers and lead to re-expression of inappropriatelyrepressed genes, proteins, and cellular functions. Due to the underlying chromatin remodeling genemutation in ATRT, HDIs are ideal candidates for therapeutic evaluation. To evaluate the role of HDIsagainst ATRT in vitro, we assessed the effect of drug treatment on proliferation, apoptosis, and geneexpression. Additionally, we examined HDI pretreatment as a radiosensitization strategy for ATRT.MTS and clonogenic assays demonstrated that HDI treatment significantly reduces the proliferativecapacity of BT-12 and BT-16 ATRT cells. Also, the HDI SNDX-275 was able to induce apoptosis in bothcell lines and induced p21Waf1/Cip1 protein expression as measured by Western blot. Evaluation ofdifferential gene expression by microarray and pathway analysis after HDI treatment demonstratedalterations of several key ATRT cellular functions. Finally, we showed that HDI pretreatmenteffectively potentiates the effect of ionizing radiation on ATRT cells as measured by clonogenic assay.These findings suggest that the addition of HDIs to ATRT therapy may prove beneficial, especiallywhen administered in combination with current treatment modalities such as radiation.
Histone deacetylase inhibition decreases proliferation and potentiates the effect of ionizing radiation in atypical teratoid/rhabdoid tumor cells.
Specimen part, Cell line
View SamplesUsing a mimic miR-200c was restored to an aggressive, Type 2 endometrial cancer cell line, Hec50
MicroRNA-200c mitigates invasiveness and restores sensitivity to microtubule-targeting chemotherapeutic agents.
Specimen part, Cell line
View SamplesThis SuperSeries is composed of the SubSeries listed below.
Expression of cilium-associated genes defines novel molecular subtypes of idiopathic pulmonary fibrosis.
Sex, Age, Specimen part
View SamplesRationale: The fibrosing idiopathic interstitial pneumonias (IIPs) are classified based on clinical, radiographic, and pathologic criteria. The separation into phenotypic subgroups is useful in predicting outcome and therapeutic strategy; however a large degree of ambiguity remains. Gene expression profiling may contribute to traditional criteria in IIPs by characterizing the dynamic biology that more accurately distinguishes subtypes of these diseases or their prognoses.
Expression of cilium-associated genes defines novel molecular subtypes of idiopathic pulmonary fibrosis.
Sex, Age, Specimen part
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