Molecular changes induced in melanoma cells by stromal cells and anti-BRAF therapy.
ABSTRACT: Tumor-associated stromal cells can enable cancer cells to become insensitive to therapy. They can promote aggressive phenotype in cancer cells, which become less responsive to drugs such as BRAF inhibitors (BRAFi) used to treat melanomas. To clarify potential mechanism behind stromal influence on melanoma, we analyzed gene expression in Melmet 5 melanoma cells grown as mono-cultures or co-cultures with lung fibroblasts with/without BRAFi. We have shown that Melmet 5 growing as co-cultures gained a de-differentiated, invasive transcriptional state, which is known to be linked to BRAFi-resistance. The transcriptional changes induced by BRAFi were much larger in Melmet 5 mono-cultures compared to co-cultures, indicating a much dampened transcriptional response to BRAFi in melanoma under the influence of fibroblasts. We conclude that interaction with the stromal cells stimulate melanoma cell transition to the invasive de-differentiated phenotype, leading to a worse response to BRAF inhibitors. Total RNA was isolated from Melmet 5 cell line growing as mono- or co-cultures with fibroblasts for 72 hours and treated with BRAFi for the last 24 hours.
Project description:We established co-cultures of invasive or non-invasive NSCLC cell lines and various types of fibroblasts (FBs) to more precisely characterize the molecular mechanism of tumor-stroma crosstalk in lung cancer Differential expression analysis of the respective mono- and co-cultures revealed an upregulation of NFκB-related genes exclusively in co-cultures with Calu-1. Cytokine Array- and ELISA-based characterization of the “cytokine fingerprints” identified CSF2 (GM-CSF), CXCL1, CXCL6, VEGF, IL6, RANTES and IL8 as being specifically upregulated in various co-cultures Overall design: 66 samples were analyzed. Epithelial Cancer Cell lines (Calu-1, HCI-H1437) and fibroblasts (HDF, WI-38, CAFs, and NFs) were cultivated in monoculture and in co-culture and hybridized on Affymetrix Exon Chips.
Project description:This experiment tested the hypothesis that distinct changes in gene expression are triggered in response to direct contact between cancer cells and fibroblasts, as opposed to co-cultures in which the cells are physically separated by membrane that permits diffusion Overall design: A431-GFP or VCAF2b-mCherry were cultured in either mono-cultures, co-cultures separated by a 0.4micron filter, or direct co-cultures followed by FACS purification.
Project description:Cancer is a disease of aging, and incidence and mortality from all cancers increase logarithmically after the age of 45. Older patients have a much poorer prognosis for melanomas of equal stage, compared to younger individuals. The role of the tumor microenvironment in modulating cancer behavior is widely recognized. We hypothesized that age-related changes in the tumor microenvironment could affect the progression of melanoma. We demonstrate that the aging microenvironment increases the invasion of melanoma cells. Using skin fibroblasts isolated from healthy donors, we have built artificial skin and demonstrate that melanoma cells invade more rapidly when exposed to aged fibroblasts. In a mouse model of melanoma (YUMM1.7, BrafV600E/Cdkn2a-/-/Pten-/-), congeneic to C57/BL6 mice, melanomas invade faster in aged mice. Gene expression analyses suggest that melanoma cells are undergoing DNA damage when exposed to an aged microenvironment, and we confirm this in cellular assays. Proteomics analysis of aging fibroblasts suggest that fibroblasts secrete molecules (laminin b2, Wnt inhibitors) associated with increased resistance to targeted therapy. Indeed, melanoma cells injected into aged mice respond less well to PLX4720 than those injected into young mice. This suggests that exciting new drugs targeting the BRAF pathway may be less effective in aging patients. Overall design: To assess the effects of the aging microenvironment on melanoma cell gene expression, we co-cultured dermal fibroblasts from young (<35 years), medium or aged ( >55 years) individuals with three different melanoma cell lines (UACC1273, M93-047 and UACC903) in triplicate using transwell chambers. After 96 h of co-culture, fibroblasts in the upper well were removed, and melanoma cells (lower chamber) were subjected to microarray analysis.
Project description:In this work, we reported a strategy to produce 3D in vitro microtissues of pancreatic ductal adenocarcinoma (PDAC) for studying the desmoplastic reaction activated by the stroma-cancer crosstalk. The purpose of this dataset was to examine the transcriptional expression changes of normal fibroblasts (NF), cancer-associated fibroblasts (CAF) and pancreatic adenocarcinoma cell line (PT45) in 3D versus 2D culture and in mono-culture versus co-culture. Illumina Human BeadChips were used to profile the transcriptome after 12 days of culture. We reported that human PDAC microtissues, obtained by co-culturing PT45 with NF or CAF within biodegradable microcarriers in spinner flask bioreactor, closely recapitulate key PDAC microenvironment characteristics. Overall design: Normal fibroblasts (NF), cancer-associated fibroblasts (CAF) and pancreatic adenocarcinoma cell line (PT45) cultured in 2D or 3D conditions for 12 days, in mono- or co-cultures.
Project description:Recent technological advances in single-cell genomics make it possible to analyze cellular heterogeneity of tumor samples. Here, we applied single-cell RNA-seq to measure the transcriptomes of 307 single cells cultured from three biopsies of three different patients with a BRAF/NRAS wild type, BRAF mutant/NRAS wild type and BRAF wild type/NRAS mutant melanoma metastasis, respectively. Analysis based on self-organizing maps identified sub-populations defined by multiple gene expression modules involved in proliferation, oxidative phosphorylation, pigmentation and cellular stroma. Gene expression modules had prognostic relevance when compared with gene expression data from published melanoma samples and patient survival data. We surveyed kinome expression patterns across sub-populations of the BRAF/NRAS wild type sample and found that CDK4 and CDK2 were consistently highly expressed in the majority of cells, suggesting that these kinases might be involved in melanoma progression. Treatment of cells with the CDK4 inhibitor palbociclib restricted cell proliferation to a similar, and in some cases greater, extent than MAPK inhibitors. Finally, we identified a low abundant sub-population in this sample that highly expressed a module containing ABC transporter ABCB5, surface markers CD271 and CD133, and multiple aldehyde dehydrogenases (ALDHs), as markers for melanoma stem or initiating cells. Patient-derived cultures of the BRAF mutant/NRAS wild type and BRAF wild type/NRAS mutant metastases showed more homogeneous single-cell gene expression patterns with gene expression modules for proliferation and ABC transporters. Taken together, our results describe an intertumor and intratumor heterogeneity in melanoma short-term cultures which might be relevant for patient survival, and suggest promising targets for new treatment approaches in melanoma therapy. Overall design: RNA-seq of 307 single cells cultured from three biopsies of three different patients with a BRAF/NRAS wild type, BRAF mutant/NRAS wild type and BRAF wild type/NRAS mutant melanoma metastasis, respectively.
Project description:Malignant melanoma is characterized by frequent metastasis, however specific changes that regulate this process have not been clearly delineated. Although it is well known that Wnt signaling is frequently dysregulated in melanoma, the functional implications of this observation are unclear. By modulating beta-catenin levels in a mouse model of melanoma that is based on melanocyte-specific Pten loss and BrafV600E mutation, we demonstrate that beta-catenin is a central mediator of melanoma metastasis to lymph node and lung. In addition to altering metastasis, beta-catenin levels control tumor differentiation and regulate both MAPK/Erk and PI3K/Akt signaling. Highly metastatic tumors with beta-catenin stabilization are very similar to a subset of human melanomas; together these findings establish Wnt signaling as a metastasis regulator in melanoma. MoGene-1_0-st-v1: Four samples total. Two biological replicates of uncultured Pten/Braf murine melanomas and two biological replicates of uncultured Pten/Braf/Bcat-STA murine melanomas. MoEx-1_0-st-v1: Two samples total. Dissociated tumor and FACS-enriched Pten/Braf and Pten/Braf/Bcat-STA murine melanoma.
Project description:Committed preadipocyte fibroblasts were genetically labelled in transgenic mice by expressing GFP under the control of the locus for Zfp423, a gene controlling preadipocyte determination. These mice are herein referred to as Zfp423-GFP mice. The overall goal was to identify genes differentially expressed between adipogenic GFP+ firboblasts and non-adipogenic GFP- fibroblasts from either inguinal or epididymal fat stromal vascular cultures obtained from Zfp423-GFP mice. Adipose stromal vascular cultures were obtained from inguinal or epididymal fat of 6-8 week-old male Zfp423-GFP mice. GFP+ and GFP- fibroblasts were sorted from fat stromal vascular cultures and then returned to culture. Subconfluent cultures of GFP+ and GFP- cells were compared in triplicate for Affymetrix analysis.
Project description:Organotypic three dimensional cultures of epithelial cells are grown at the air–liquid interface (ALI) and resemble the in vivo counterparts. Although the complexity of in vivo cellular responses could be better manifested in co-culture models in which additional cell-types such as fibroblasts were incorporated, the presence of another cell-type could mask the response of the other. This study reports the impact of whole combustible cigarette smoke (CS) on organotypic mono- and co-culture models to evaluate the relevancy of organotypic models for toxicological assessment of aerosols. Two organotypic bronchial models were directly exposed to low and high concentrations of CS of the reference research cigarette 3R4F: mono-culture of bronchial epithelial cells without fibroblasts (BR) and co-culture with fibroblasts (BRF) models. Adenylate kinase-based cytotoxicity, cytochrome P450 (CYP) 1A1/1B1 activity, tissue histology, and concentrations of secreted mediators in the basolateral media, as well as transcriptomes were evaluated following the CS exposure. The results demonstrated similar impact of CS on the AK-based cytotoxicity, CYP1A1/1B1 activity, and tissue histology in both models. However, a greater number of secreted mediators were found in the basolateral media of the mono-culture than in the co-culture models. Furthermore, annotation analysis and network-based systems biology analysis of the transcriptomic profiles indicated a more prominent cellular stress and tissue damage following CS in the mono-culture epithelium model without fibroblasts. Finally, our results indicated that the in vivo smoking-induced xenobiotic metabolism response in the bronchial epithelial cells was better reflected on the in vitro co-culture model upon CS exposure.
Project description:The signaling events triggered by soluble mediators released from both transformed and stromal cells shape the phenotype of tumoral cells and have significant implications in cancer development and progression. In this study we performed an in vitro heterotypic signaling assay by evaluating the proteome diversity of human dermal fibroblasts after stimulation with the conditioned media obtained from malignant melanoma cells. In addition, we also evaluated the changes in the proteome of melanoma cells after stimulation with their own conditioned media as well as with the conditioned medium from melanoma-stimulated fibroblasts. Our results pointed out to a significant rearrangement in the proteome of stromal and malignant cells upon crosstalk of soluble mediators. The main proteome signature of stimulated cells was related to protein synthesis, which may indicate that this process might be an early response of stimulated stromal cells. In addition, the conditioned medium derived from ‘primed’ stromal cells (melanoma-stimulated fibroblasts) was more effective in altering the functional phenotype (cell migration) of malignant cells than the fibroblast conditioned medium alone. Collectively, self- and cross-stimulation may play a key role in shaping the tumor microenvironment and, more importantly, enable tumoral cells to succeed in the process of melanoma progression and metastasis. Although the proteome landscape of cells participating in such a heterotypic signaling represents a snapshot of a highly dynamic state, understanding the diversity of proteins and enriched biological pathways resulting from stimulated cell states may allow for targeting specific cell regulatory motifs involved in melanoma progression and metastasis.
Project description:We have previously shown that Wnt5A drives invasion in melanoma. We have also shown that Wnt5A promotes resistance to therapy designed to target the BRAF(V600E) mutation in melanoma. Here, we show that melanomas characterized by high levels of Wnt5A respond to therapeutic stress by increasing p21 and expressing classical markers of senescence, including positivity for senescence-associated β-galactosidase (SA-β-gal), senescence-associated heterochromatic foci (SAHF), H3K9Me chromatin marks, and PML bodies. We find that despite this, these cells retain their ability to migrate and invade. Further, despite the expression of classic markers of senescence such as SA-β-gal and SAHF, these Wnt5A-high cells are able to colonize the lungs in in vivo tail vein colony-forming assays. This clearly underscores the fact that these markers do not indicate true senescence in these cells, but instead an adaptive stress response that allows the cells to evade therapy and invade. Notably, silencing Wnt5A reduces expression of these markers and decreases invasiveness. The combined data point to Wnt5A as a master regulator of an adaptive stress response in melanoma, which may contribute to therapy resistance. To better understand the molecular mechanisms governing the response of highly invasive cells to IR as compared to that of poorly invasive cells, we performed microarray analysis of both poorly and highly invasive cells at early and late timepoints after irradiation. Cells were treated with y-irradiation, and RNA was taken at 1 hour, 24 hours and 5 days after irradiation. Microarray analysis was performed using Illumina Human HT-12 ver3 expression arrays, and each time point was compared to RNA from untreated cells.