Breast Cancer Cell Density: Imaging assay of the density- and context-dependence of small molecule perturbagen response in breast cancer cell lines. Dataset 3 of 3: Calculated dose-response metrics.
Project description:In previous studies, we identified a distantly related rhomboid homologue gene known as RHBDD2 (Rhomboid domain containing 2) to be markedly overexpressed in the advanced stages of the breast and colorectal cancer diseases. In order to identify RHBDD2 modulated pathways, we analyzed two breast cancer cell lines (MCF7 and T47D) from control and RHBDD2-siRNA transient gene silencing followed by gene expression profiling analysis using the whole genome Toray 3D-GeneTM Human Oligo Chip. Statistical analysis of the Toray's 3D gene expression profiling data identified 566 commonly differentially expressed genes in association to the RHBDD2 knockdown in both breast cancer cell lines. Among the statistically significant over-represented biological process, we found the apoptosis, cell cycle and response to DNA damage process related genes. In addition, categories of genes found in the ubiquitin-proteasome and oxidative phosphorylation were also highly enriched related genes in the commonly deregulated gene list. We further used a lentivirus-based system (shRNA-pLKO.1) for stable silencing of RHBDD2 mRNA in the T47D breast cancer cell line. Using a staurosporine-induced apoptosis model, we demonstrate that RHBDD2 abrogation resulted in an apoptosis-resistant phenotype of T47D breast cancer cell line. These data are in line with a recent study, suggesting that RHBDD2 expression could be up-modulated in response to 5FU-induced apoptosis in colorectal cancer cells. Taken together, these data suggest that RHBDD2 could be involved in the modulation of the programmed cell death in cancer cells. In order to analyze differential gene expression profiling of RHBDD2 silencing and control cells, total RNA was isolated from replicate experiments from two breast cancer cell lines (MCF7 and T47D) derived from the negative control-siRNA and the RHBDD2-siRNA treatments in duplicate experiments.
Project description:PurposeTo evaluate the efficacy of Library of Integrated Network-based Cellular Signatures (LINCS) perturbagen prediction software to identify small molecules that revert pathologic gene signature and alter disease phenotype in orbital adipose stem cells (OASCs) derived from patients with thyroid-associated orbitopathy (TAO).MethodsDifferentially expressed genes identified via RNA sequencing were inputted into LINCS L1000 Characteristic Direction Signature Search Engine (L1000CDS2) to predict candidate small molecules to reverse pathologic gene expression. TAO OASC cell lines were treated in vitro with six identified small molecules (Torin-2, PX12, withaferin A, isoliquiritigenin, mitoxantrone, and MLN8054), and expression of key adipogenic and differentially expressed genes was measured with quantitative polymerase chain reaction after 7 days of treatment. OASCs were differentiated into adipocytes, treated for 15 days, and stained with Oil Red O (OD 490 nm) to evaluate adipogenic changes.ResultsThe expression of key differentially expressed genes (IRX1, HOXB2, S100B, and KCNA4) and adipogenic genes (peroxisome proliferator activated receptor-γ, FABP4) was significantly decreased in TAO OASCs after treatment (P < .05). In treated TAO adipocytes (n = 3), all six tested small molecules yielded significant decrease (P < .05) in Oil Red O staining. In treated non-TAO adipocytes (n = 3), only three of the drugs yielded a significant decrease in Oil Red O staining.ConclusionsCombining disease expression signatures with LINCS small molecule prediction software can identify promising preclinical drug candidates for TAO.Translational relevanceThese findings may offer insight into future potential therapeutic options for TAO and demonstrate a streamlined model to predict drug candidates for other diseases.
Project description:Drug resistance in breast cancer is the major obstacle to a successful outcome following chemotherapy treatment. While upregulation of multidrug resistance (MDR) genes is a key component of drug resistance in multiple cancers, the complexity and hierarchy of non-MDR driven drug resistance pathways are still largely unknown. The aim of this study was to identify pathways contributing to anthracycline resistance using isogenic drug resistant breast cancer cell lines. We generated isogenic MDA-MB-231, MCF7, SKBR3 and ZR-75-1 epirubicin-resistant breast cancer cell lines, which were cross-resistant to doxorubicin and SN-38; the SKBR3 cell line was also resistant to taxanes. Epirubicin-resistant cells were morphologically different from native cells, and had alterations in apoptosis and cell cycle profile. Using gene expression and small-molecule inhibitor analyses we identified deregulation of histone H2A and H2B genes in all four cell lines. These genes contribute to several biological pathways, which include cell cycle, chromosomal maintenance, epigenetics, RNA and mitochondrial transcription. Histone deacetylase and cell cycle/DNA damage small molecule inhibitors reversed resistance and were cytotoxic for all four epirubicin-resistant cell lines confirming that histone and cell cycle pathways are associated with epirubicin resistance. This study has established model systems for investigating drug resistance in all four breast cancer subtypes and revealed key pathways that contribute to anthracycline resistance. The global gene expression analysis included 4 parental (anthracycline sensitive) and 4 resistant breast cancer cell lines, in biological triplicates.
Project description:Introduction: Breast radiotherapy is currently â??one size fits allâ?? regardless of breast cancer subtype (eg. luminal, basal). However, recent clinical data suggests that radiation response may vary significantly among subtypes. Therefore, current practice leads to over- or under-treatment of women whose tumors are more or less radiation responsive. We hypothesized that this clinical variability may be due, in part, to differences in cellular radiation response. Methods: We exposed 16 biologically-diverse breast tumor cell lines to 0 or 5GY radiation. Microarray analysis was performed on RNA harvested from those cell lines. Samples were run in triplicate. Following quality assessment, differential gene expression analysis was performed using a two-way multiplicative linear mixed-effects model. A candidate radiation response biomarkers with biologically plausible role in radiation response, were identified and confirmed at the RNA and protein level with qPCR and Western blotting assays. Induction in human breast tumors was confirmed in 32 patients with paired pre- and post-radiation tumor samples using IHC and microarray analysis. Quantification of protein was performed in a blinded manner and included positive and negative controls. The objective of our study was to identify genomic determinants of radiation sensitivity using clinical samples as well as breast tumor cell lines. In order to identify differences in the radiation response gene expression profiles of specific breast cancer subtypes, we exposed 16 biologically-diverse breast tumor cell lines to 0 or 5GY radiation. Microarray analysis was performed on RNA harvested from those cell lines. Samples were run in triplicate. Following quality assessment, differential gene expression analysis was performed using a two-way multiplicative linear mixed-effects model. Candidate radiation response biomarker with a biologically plausible role in radiation response, were identified and confirmed at the RNA and protein level with qPCR and Western blotting assays. Induction of the genes of interest were further evaluated and confirmed in human breast tumors in 32 breast cancer patients with paired pre- and post-radiation tumor samples using IHC and microarray analysis assays.
Project description:To address the challenges associated with the investigation of brain-metastasized cancers and provide insights into the drivers of cancer cell behavior at the brain metastatic site, this study was aimed at exploring the response of SKBR3/HER2+ cells to neural factors secreted by brain cells that come first in contact with the metastasized cancer cells, i.e., human endothelial cells (HBEC5i), astrocytes (NHA), and microglia (HMC3). To this end, serum-starved breast cancer cells were exposed to the combined secretome of brain cells, allowed to grow for 24h, and analyzed by LC-MS/MS using an Orbitrap QE instrument to generate and compare the whole cell proteome profiles of treated vs non-treated cells.
Project description:To explore the broader impact of kinase inhibitors on breast cancer cells, SKBR3/HER2+ cells were treated with two small molecule drugs, i.e., Lapatinib (10 uM) - a Tyr kinase inhibitor, and Ipatasertib (1 uM) - a Ser/Thr kinase inhibitor. Serum-starved cells (24 h) were exposed for 36 h to Lapatinib/EGF or a combination of Lapatinib/Ipatasertib/EGF. EGF - only stimulated cells were used as control. The EGF concentration was 10 nM throughout all experiments. Proteomic profiles of nuclear and cytoplasmic cell fractions of treated vs non-treated cells were generated by nano-LC-MS/MS using an Orbitrap QE instrument.