Protein homeostasis in the endoplasmic reticulum (ER) has recently emerged as a therapeutic target for cancer treatment. Disruption of ER homeostasis results in ER stress, which is a major cause of cell death for cells exposed to the proteasome inhibitor Bortezomib, an anti-cancer drug approved for treatment of multiple myeloma and Mantle cell lymphoma. We recently reported that the ERAD inhibitor Eeyarestatin I (EerI) also disturbs ER homeostasis and has anti-cancer activities resembling that of Bortezomib.
The ERAD inhibitor Eeyarestatin I is a bifunctional compound with a membrane-binding domain and a p97/VCP inhibitory group.
Cell line
View SamplesSmall subsets of B cells in the germinal center (GC) and in extrafollicular regions of lymph nodes express the activation marker CD30. Very little is known about the specific features of these cells and their relationship to the CD30-expressing Hodgkin and Reed/Sternberg (HRS) cells of Hodgkin lymphoma. Phenotypic and immunoglobulin V gene analyses revealed that CD30+ GC B lymphocytes represent typical GC B cells, and that CD30+ non-GC B cells are mostly post-GC B cells. However, despite these seemingly distinct identities, both CD30+ subsets share an unexpectedly large overlap in specific transcriptome patterns, and are strikingly different from bulk GC B cells and classical memory and plasma cells, respectively. A main common feature of these CD30+ B cells is a strong MYC signature. CD30+ GC B cells appear to represent the recently described MYC+ GC B cell subset of recirculating centrocytes at the stage of centroblast transition. CD30+ non-GC B cells rather represent highly activated and proliferating memory B cells, differentiating into plasma cells. Notably, CD30+ B cells were more similar in their transcriptome patterns to HRS cells than any other B cell subset investigated, suggesting that HRS cells may either derive from CD30+ B cells or acquired a similar activation signature. In comparison to CD30+ B cells and other lymphomas, HRS cells show a remarkable downregulation of genes regulating cell cycle, genomic stability and polyploidity, providing a potential explanation for the genomic instability and multinuclearity of HRS cells.
Human CD30+ B cells represent a unique subset related to Hodgkin lymphoma cells.
Specimen part
View SamplesThe ubiquitin-proteasome system (UPS) has recently emerged as a major target for drug development in cancer therapy. The proteasome inhibitor bortezomib has clinical activity in multiple myeloma and mantle cell lymphoma. Here we report that Eeyarestatin I (EerI), a chemical inhibitor that blocks ER-associated protein degradation (ERAD), has anti-tumor and biologic activities similar to bortezomib, and can synergize with bortezomib. Like bortezomib, EerI-induced cytotoxicity requires the upregulation of the BH3 only pro-apoptotic protein NOXA. We further demonstrate that both EerI and bortezomib activate NOXA via an unanticipated mechanism that requires cooperation between two processes: First, these agents elicit an integrated stress response program at the ER to activate the CREB/ATF transcription factors ATF3 and ATF4. We show that ATF3 and ATF4 form a complex capable of binding to the NOXA promoter, which is required for NOXA activation. Second, EerI and bortezomib also block ubiquitination of histone H2A to relieve its inhibition on NOXA transcription. Our results identify a class of anti-cancer agents that integrate ER stress response with an epigenetic mechanism to induce cell death.
ERAD inhibitors integrate ER stress with an epigenetic mechanism to activate BH3-only protein NOXA in cancer cells.
No sample metadata fields
View SamplesGene expression profiles were compared between L-428 HRS cells transduced with shRNA against AP-1 transcription factor BATF3 and L-428 HRS cells transduced with a non-targeting shRNA as control.
An oncogenic axis of STAT-mediated BATF3 upregulation causing MYC activity in classical Hodgkin lymphoma and anaplastic large cell lymphoma.
Specimen part
View SamplesWe provide direct in vivo evidence for activation of the BCR and canonical NF-KB pathways in MCL that, in the absence of activating mutations, is dependent on the lymph node microenvironment.
Pathogenic role of B-cell receptor signaling and canonical NF-κB activation in mantle cell lymphoma.
Specimen part
View SamplesWe provide direct in vivo evidence for activation of the BCR and canonical NF-KB pathways in MCL that, in the absence of activating mutations, is dependent on the lymph node microenvironment. This finding provides a mechanistic explanation for the surprising efficacy of ibrutinib for the treatment of this type of lymphoma. Mutations in components of the BCR and NF-KB pathways are associated with cell-autonomous signaling and resistance to ibrutinib. Overall design: Lymph node biopsies and peripheral blood samples were obtained from patients with previously untreated MCL.
Pathogenic role of B-cell receptor signaling and canonical NF-κB activation in mantle cell lymphoma.
No sample metadata fields
View SamplesBortezomib-induced resistant MCL cell lines (HBL2 BR and JEKO BR) were generated by continuous cultured of corresponding parental cell lines (HBL2 PT and JEKO PT) with increasing bortezomib concentrations
Bortezomib resistance in mantle cell lymphoma is associated with plasmacytic differentiation.
Specimen part, Cell line
View SamplesMantle Cell Lymphoma (MCL) is a mostly incurable malignancy arising from nave B cells (NBC) in the mantle zone of lymph node follicles. We analyzed genome-wide methylation in MCL patients using the HELP (Hpa II tiny fragment Enrichment by Ligation mediated PCR) assay and found significant aberrancy in promoter methylation patterns as compared to normal NBCs. Using biological and stringent statistical criteria, we further identified four hypermethylated genes CDKN2B, MLF-1, PCDH8, HOXD8 and four hypomethylated genes CD37, HDAC1, NOTCH1 and CDK5 where aberrant methylation was associated with inverse changes in mRNA levels. MassArray Epityper analysis confirmed the presence of differential methylation at the promoter region of these genes. Immunohistochemical analysis of an independent cohort of 14 MCL patient samples, confirmed CD37 surface expression in 93% of patients, validating its selection as a target for MCL therapy. Treatment of MCL cell lines with a novel small modular immunopharmaceutical(CD37-SMIP) resulted in significant loss of viability in cell lines with intense surface CD37 expression. Treatment of MCL cell lines with the DNA methyltransferase inhibitor decitabine resulted in reversal of aberrant hypermethylation and synergized with the HDAC inhibitor SAHA in induction of the four hypermethylated genes CDKN2B, MLF-1, PCDH8 and HOXD8. The combination of Decitabine and SAHA also resulted in potent and synergistic anti-MCL cytotoxicity as compared to either drug alone. In conclusion, our analysis shows prominent and aberrant methylation of the MCL genome and identifies novel differentially methylated and expressed genes in MCL cell lines and patient samples. Furthermore, our data suggest that differentially methylated genes can be targeted for therapeutic benefit in MCL.
Genomewide DNA methylation analysis reveals novel targets for drug development in mantle cell lymphoma.
Disease, Cell line
View SamplesProgression to malignancy requires cells to overcome senescence and switch to an immortal phenotype. Thus, exploring the genetic and epigenetic changes that occur during senescence/immortalization may help elucidate crucial events that lead to cell transformation. In the present study, we have globally profiled DNA methylation in relation to gene expression in primary, senescent and immortalized mouse embryonic fibroblasts.
Mammalian cells acquire epigenetic hallmarks of human cancer during immortalization.
Specimen part
View SamplesAlzheimer's disease (AD) is characterized by massive neurodegeneration and multiple changes in cellular processes, including neurogenesis. Proteolytic processing of the amyloid precursor protein (APP) plays a central role in AD. Due to varying APP processing, several beta-amyloid peptides are generated. In contrast to the form with 40 amino acids, the variant with 42 amino acids is thought to be the pathogenic form triggering the pathophysiological cascade in AD. Here, we studied the transcriptomic response to increased or decreased Abeta42 levels generated in human neuroblastoma cells. Genome-wide expression profiles (Affymetrix)were used to analyze the cellular response to the changed Abeta42 and Abeta40-levels. <br></br><br></br>Human neuroblastoma cell line SH-SY5Y is a thrice cloned (SK-N-SH -> SH-SY -> SH-SY5 -> SH-SY5Y) subline of the neuroblastoma cell line SK-N-SH which was isolated and established in 1970. This cell line has 47 chromosomes. The cells possess a unique marker comprised of a chromosome 1 with a complex insertion of an additional copy of a 1q segment into the long arm, resulting in trisomy of 1q. The cell lines used in this study are SHSY5Y transfected with the constructs pCEP-C99I45F, pCEP-C99V50F, pCEP-C99 wildtype or mock transfected with an empty vector. Independent cell clones of each transfected line were used to provide biological replicates.<br></br> Overexpressed C99 I45F is intracellularly cleaved resulting in high Abeta42, but low Abeta40 levels.<br></br> Overexpressed C99V50F is intracellularly cleaved resulting in low Abeta42, but high Abeta40 levels.<br></br>Overexpressed C99 wildtype is intracellularly cleaved resulting in medium Abeta42 and Abeta40 levels<br></br>Mock is the SHSY5Y cell line transfected with the empty vector pCEP (Invitrogen) as a negative control
New Alzheimer amyloid beta responsive genes identified in human neuroblastoma cells by hierarchical clustering.
Cell line, Subject
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