HDAC inhibition induces transient phenotypic inertia in dormant OCCC spheroids by derepression of cell cycle genes
Ontology highlight
ABSTRACT:
ORGANISM(S): Homo sapiens
PROVIDER: GSE320019 | GEO | 2026/05/15
REPOSITORIES: GEO
Similar Datasets
Project description:Cancer cell spheroids autonomously form in the ascites fluid and are considered a conduit for epithelial ovarian cancer metastasis within the peritoneal cavity. Spheroids are homotypic, avascular, 3D structures that acquire resistance to anoikis to remain viable after cellular detachment. We used in vitro spheroid model systems to interrogate pathways critical for spheroid cell proliferation, distinct from those driving monolayer cancer cell proliferation. Using the 105C and KOC-7c human ovarian clear cell carcinoma (OCCC) cell lines, which have distinct proliferative phenotypes as spheroids but the same prototypical OCCC gene mutation profile of constitutively activated AKT signaling with loss of ARID1A, we revealed therapeutic targets that efficiently kill cells in spheroids. RNA-seq analyses compared the transcriptome of 3-day monolayer and spheroid cells from these lines and identified the characteristics of dormant spheroid cell survival which included the G2/M checkpoint, autophagy, and other stress pathways induced in 105C spheroids, in sharp contrast to the proliferating spheroid cells of the KOC-7c cell line. Next, we assessed levels of various G2/M checkpoint regulators and found a consistent reduction in steady-state levels of checkpoint regulators in dormant spheroid cells but not proliferative spheroids. Our studies showed that proliferative spheroid cells were sensitive to Wee1 inhibition by AZD1775, but the dormant spheroid cells showed a degree of resistance to AZD1775, both in terms of EC50 values and spheroid reattachment abilities. In doing so, we have identified biomarkers of dormant spheroids, including the G2/M checkpoint regulators Wee1, Cdc25c, and PLK1, and showed that, when compared to proliferating spheroid cells, the transcriptome of dormant OCCC spheroids is a source for therapeutic targets.
2025-06-18 | GSE294002 | GEO
Project description:Background: Ewing sarcoma (EwS) are characterized by oncogenic chimeric EWS-ETS proteins. EZH2 is upregulated via predominant EWS-FLI1 in EwS. RNAi of EZH2 revealed an EZH2-maintained, undifferentiated, stemness phenotype. Herein, microarray analysis demonstrated that treatment with HDAC inhibitors (HDACi) entinostat or TSA resulted in the induction of a similar pattern of differentiation genes as observed after EZH2 RNAi. This indicates that EZH2-containing PRC2 complexes may serve as a building block of class I HDAC activity in EwS. Methods: The role of class I HDACs was determined using different inhibitors including TSA, romidepsin (FK228), entinostat (MS-275) and PCI-34051 as well as CRISPR/Cas9 class I HDAC knock outs and HDAC RNAi. To analyze resulting changes microarray and gene set enrichment analysis (GSEA), qRT-PCR, western blotting, Co-IP, proliferation, apoptosis, differentiation, invasion assays and xenograft-mouse models were used. Results: Class I HDACs are constitutively expressed in EwS. They seem regulated via EWS-FLI1. Interestingly, patients with high levels of individual class I HDAC expression show decreased overall survival. CRISPR/Cas9 class I HDAC knock out of individual HDACs such as HDAC1 and HDAC2 inhibited growth, invasiveness, and blocked local tumor growth in xenograft mice. Microarray and GSEA analysis demonstrated that treatment with individual HDAC inhibitors (HDACi) blocked an EWS-FLI1 specific expression profile, while entinostat in addition suppressed metastasis relevant genes. EwS cells demonstrated increased susceptibility to treatment with first line chemotherapeutics including doxorubicin in the presence of HDACi. Furthermore, HDACi treatment mimicked RNAi of EZH2 in EwS. Treated cells showed diminished growth capacity, but an increased endothelial as well as neuronal differentiation ability. HDACi synergizes with EED inhibitor (EEDi) in vitro and together inhibited tumor growth in xenograft mice. Co-IP experiments identified HDAC class I family members as part of a regulatory complex together with PRC2. Conclusion: Class I HDAC proteins seem to be important mediators of the pathognomonic EWS-ETS-mediated transcription program in EwS and in combination therapy, co-treatment with HDACi are interesting new treatment opportunities for this malignant disease.
2021-10-20 | GSE162788 | GEO
Project description:Background: Ewing sarcoma (EwS) are characterized by oncogenic chimeric EWS-ETS proteins. EZH2 is upregulated via predominant EWS-FLI1 in EwS. RNAi of EZH2 revealed an EZH2-maintained, undifferentiated, stemness phenotype. Herein, microarray analysis demonstrated that treatment with HDAC inhibitors (HDACi) entinostat or TSA resulted in the induction of a similar pattern of differentiation genes as observed after EZH2 RNAi. This indicates that EZH2-containing PRC2 complexes may serve as a building block of class I HDAC activity in EwS. Methods: The role of class I HDACs was determined using different inhibitors including TSA, romidepsin (FK228), entinostat (MS-275) and PCI-34051 as well as CRISPR/Cas9 class I HDAC knock outs and HDAC RNAi. To analyze resulting changes microarray and gene set enrichment analysis (GSEA), qRT-PCR, western blotting, Co-IP, proliferation, apoptosis, differentiation, invasion assays and xenograft-mouse models were used. Results: Class I HDACs are constitutively expressed in EwS. They seem regulated via EWS-FLI1. Interestingly, patients with high levels of individual class I HDAC expression show decreased overall survival. CRISPR/Cas9 class I HDAC knock out of individual HDACs such as HDAC1 and HDAC2 inhibited growth, invasiveness, and blocked local tumor growth in xenograft mice. Microarray and GSEA analysis demonstrated that treatment with individual HDAC inhibitors (HDACi) blocked an EWS-FLI1 specific expression profile, while entinostat in addition suppressed metastasis relevant genes. EwS cells demonstrated increased susceptibility to treatment with first line chemotherapeutics including doxorubicin in the presence of HDACi. Furthermore, HDACi treatment mimicked RNAi of EZH2 in EwS. Treated cells showed diminished growth capacity, but an increased endothelial as well as neuronal differentiation ability. HDACi synergizes with EED inhibitor (EEDi) in vitro and together inhibited tumor growth in xenograft mice. Co-IP experiments identified HDAC class I family members as part of a regulatory complex together with PRC2. Conclusion: Class I HDAC proteins seem to be important mediators of the pathognomonic EWS-ETS-mediated transcription program in EwS and in combination therapy, co-treatment with HDACi are interesting new treatment opportunities for this malignant disease.
2021-10-20 | GSE162786 | GEO
Project description:Background: Ewing sarcoma (EwS) are characterized by oncogenic chimeric EWS-ETS proteins. EZH2 is upregulated via predominant EWS-FLI1 in EwS. RNAi of EZH2 revealed an EZH2-maintained, undifferentiated, stemness phenotype. Herein, microarray analysis demonstrated that treatment with HDAC inhibitors (HDACi) entinostat or TSA resulted in the induction of a similar pattern of differentiation genes as observed after EZH2 RNAi. This indicates that EZH2-containing PRC2 complexes may serve as a building block of class I HDAC activity in EwS. Methods: The role of class I HDACs was determined using different inhibitors including TSA, romidepsin (FK228), entinostat (MS-275) and PCI-34051 as well as CRISPR/Cas9 class I HDAC knock outs and HDAC RNAi. To analyze resulting changes microarray and gene set enrichment analysis (GSEA), qRT-PCR, western blotting, Co-IP, proliferation, apoptosis, differentiation, invasion assays and xenograft-mouse models were used. Results: Class I HDACs are constitutively expressed in EwS. They seem regulated via EWS-FLI1. Interestingly, patients with high levels of individual class I HDAC expression show decreased overall survival. CRISPR/Cas9 class I HDAC knock out of individual HDACs such as HDAC1 and HDAC2 inhibited growth, invasiveness, and blocked local tumor growth in xenograft mice. Microarray and GSEA analysis demonstrated that treatment with individual HDAC inhibitors (HDACi) blocked an EWS-FLI1 specific expression profile, while entinostat in addition suppressed metastasis relevant genes. EwS cells demonstrated increased susceptibility to treatment with first line chemotherapeutics including doxorubicin in the presence of HDACi. Furthermore, HDACi treatment mimicked RNAi of EZH2 in EwS. Treated cells showed diminished growth capacity, but an increased endothelial as well as neuronal differentiation ability. HDACi synergizes with EED inhibitor (EEDi) in vitro and together inhibited tumor growth in xenograft mice. Co-IP experiments identified HDAC class I family members as part of a regulatory complex together with PRC2. Conclusion: Class I HDAC proteins seem to be important mediators of the pathognomonic EWS-ETS-mediated transcription program in EwS and in combination therapy, co-treatment with HDACi are interesting new treatment opportunities for this malignant disease.
2021-10-20 | GSE162785 | GEO
Project description:Ovarian clear cell carcinoma (OCCC) is a rare subtype of gynecological cancer for which well-characterized and authenticated model systems are scarce. We provide an extensive characterization of ‘105C’, a cell line generated from an adenocarcinoma of the clear cell histotype using targeted next-generation sequencing, cytogenetic microarrays, along with analyses of AKT/mTOR signaling. We report that that the 105C cell line is a bona fide OCCC cell line, carrying PIK3CA, PTEN, and ARID1A gene mutations, consistent with OCCC, yet maintain a stable genome as reflected by low copy number variation. Unlike KOC-7c, TOV-21G, and RMG-V OCCC lines also mutated for the above genes, the 105C cells do not carry mutations in mismatch repair genes. Importantly, we show that 105C cells exhibit greater resistance to mTOR inhibition and carboplatin treatment compared to 9 other OCCC cell lines in 3D spheroid cultures. This resistance may be attributed to 105C cells remaining dormant in suspension culture which surprisingly, contrasts with several other OCCC lines which continue to proliferate in long-term suspension culture. 105C cells survive xenotransplantation but do not proliferate and metastasize. Collectively, we show that the 105C OCCC cell line exhibits unique properties useful for the pre-clinical investigation of OCCC pathobiology.
2020-11-01 | GSE160570 | GEO
Project description:Ovarian clear cell carcinoma (OCCC) is a rare subtype of gynecological cancer for which well-characterized and authenticated model systems are scarce. We provide an extensive characterization of ‘105C’, a cell line generated from an adenocarcinoma of the clear cell histotype using targeted next-generation sequencing, cytogenetic microarrays, along with analyses of AKT/mTOR signaling. We report that that the 105C cell line is a bona fide OCCC cell line, carrying PIK3CA, PTEN, and ARID1A gene mutations, consistent with OCCC, yet maintain a stable genome as reflected by low copy number variation. Unlike KOC-7c, TOV-21G, and RMG-V OCCC lines also mutated for the above genes, the 105C cells do not carry mutations in mismatch repair genes. Importantly, we show that 105C cells exhibit greater resistance to mTOR inhibition and carboplatin treatment compared to 9 other OCCC cell lines in 3D spheroid cultures. This resistance may be attributed to 105C cells remaining dormant in suspension culture which surprisingly, contrasts with several other OCCC lines which continue to proliferate in long-term suspension culture. 105C cells survive xenotransplantation but do not proliferate and metastasize. Collectively, we show that the 105C OCCC cell line exhibits unique properties useful for the pre-clinical investigation of OCCC pathobiology. Copy number variation was determined for multiple Ovarian Clear Cell Carcinomas
2020-11-01 | GSE160569 | GEO
Project description:Cbx7 knockdown resulted in increase of genes related with apoptosis and inflammation. Expression microarray was performed using RNA extracted from 2 ovarian clear cell adenocarcinoma cell lines, namely, KOC-7C and TOV21G, either trancduced by Cbx7 siRNA or control.
2013-11-01 | E-GEOD-47146 | biostudies-arrayexpress
Project description:Purpose: Gastric cancer remains one of the deadliest neoplasms worldwide, with a high need for new therapeutic options. Efficacies of targeted therapies are often limited owing to the inter- and intratumoral heterogeneity of gastric cancer. Thus, drugs with broader mechanisms of action rather than relying on the inhibition of a single specific oncogene are needed. Preclinical studies have identified histone deacetylases (HDAC) and their respective isoforms as potential therapeutic targets in gastric cancer. However, clinical efficacies are moderate and the mechanism(s) of action of HDAC inhibitors (HDACi) are only partially understood. Methods: In a panel of gastric cancer cell lines with different molecular characteristics, tumor cell inhibitory effects of different HDACi were studied. Lipid peroxidation levels were measured using flow cytometry. Proteome analysis was performed for the in-depth characterization of molecular alterations upon HDAC inhibition. HDACi effects on important ferroptosis genes were validated on the mRNA (RT-qPCR) and protein level (Western Blot). Results: Upon HDACi treatment, lipid peroxidation levels were found increased in all tested cell lines. Class-I HDACi (VK1, entinostat) showed the same toxicity profile as the pan-HDACi vorinostat. Proteome analysis revealed significant and concordant alterations in the expression of proteins related to ferroptosis induction. Key enzymes like ACSL4, POR or SLC7A11 showed distinct alterations in their expression patterns, providing an explanation for the increased lipid peroxidation. Alterations of POR and SLC7A11 levels upon treatment were also confirmed in primary human gastric cancer tissue cultures as relevant ex vivo model. Conclusion: We identify the induction of ferroptosis as a new mechanism of action of class-I HDACi in gastric cancer. Notably, these findings were independent of the genetic background of the cell lines, thus introducing HDAC inhibition as a more general therapeutic principle besides other, less broadly usable targeted drugs.
2024-05-21 | PXD050328 | Pride
Project description:Checkpoint immunotherapy unleashes tumor control by T cells, but it is undermined in non-immunogenic tumors, e.g. with low MHC class I expression and low neoantigen burden, such as neuroblastoma (NB). Endoplasmic reticulum aminopeptidase 1 (ERAP1) is an enzyme that trims peptides before loading on MHC class I molecules. Inhibition of ERAP1 results in the generation of new antigens able of inducing potent anti-tumor immune responses. Here, we identify a novel non-toxic combinatorial strategy based on genetic inhibition of ERAP1 and administration of the HDAC inhibitor (HDACi) entinostat that increase the immunogenicity of NB, making it responsive to PD-1 therapy.
2025-05-07 | PXD055268 | Pride
Project description:MYC-driven Group 3 medulloblastoma (MB) (subtype II) is a highly aggressive childhood brain tumor. Sensitivity of MYC-driven MBs to class I histone deacetylase inhibitors (HDACi) has been previously demonstrated in vitro and in vivo. We here characterize the transcriptional effects of class I HDAC inhibition in MYC-driven MB and explore beneficial drug combinations. MYC-amplified Group 3 MB cells (HD-MB03) were treated with class I HDACi entinostat. Changes in the gene expression profile compared to untreated control were quantified on a microarray. Gene set enrichment analysis, cytoscape enrichment mapping and ingenuity pathway analysis led to the identification of pathways affected by entinostat treatment. Five drugs interfering with these pathways (olaparib, idasanutlin, ribociclib, selinexor, vinblastine) were tested as single agents in metabolic activity assays in three MYC-amplified and two non-MYC-amplified MB cell lines. Synergy with entinostat was evaluated by dose response curve shift, combination index and zero interaction potency synergy model and validated in cell count and flow cytometry experiments in two MYC-amplified and one non-MYC-amplified MB cell line. The effect of the most promising drug combination (entinostat and olaparib) on DNA damage was evaluated by γH2A.X quantification in immunoblotting, fluorescence microscopy and flow cytometry. Entinostat treatment changed the expression of genes involved in 22 pathways, including downregulation of DNA damage response. The PARP1 inhibitors olaparib and pamiparib showed synergy with entinostat. The combination of entinostat and olaparib led to increased cell death, decreased viability and increased formation of double strand breaks selectively in MYC-amplified MB cells. MYC-amplified MB cells treated with entinostat and olaparib were particularly vulnerable to additional induction of DNA damage by doxorubicin. Non-MYC-amplified MB cells and normal human fibroblasts were not susceptible to this triple treatment. Our study identifies the combination of entinostat with olaparib and doxorubicin as a new potential therapeutic approach for MYC-driven Group 3 MB.
2023-10-04 | GSE232148 | GEO