Mesothelioma-associated fibroblasts enhance proliferation and migration of pleural mesothelioma cells via c-Met/PI3K and WNT signaling but do not protect against cisplatin

Abstract

Background Pleural mesothelioma (PM) is an aggressive malignancy with poor prognosis. Unlike many other cancers, PM is mostly characterized by inactivation of tumor suppressor genes. Its highly malignant nature in absence of tumor driving oncogene mutations indicates an extrinsic supply of stimulating signals by cells of the tumor microenvironment (TME). Cancer-associated fibroblasts (CAFs) are an abundant cell type of the TME and have been shown to drive the progression of several malignancies. The aim of the current study was to isolate and characterize patient-derived mesothelioma-associated fibroblasts (Meso-CAFs), and evaluate their impact on PM cells. Methods Meso-CAFs were isolated from surgical specimens of PM patients and analyzed by array comparative genomic hybridization, next generation sequencing, transcriptomics and proteomics. Human PM cell lines were retrovirally transduced with GFP. The impact of Meso-CAFs on tumor cell growth, migration, as well as the response to small molecule inhibitors, cisplatin and pemetrexed treatment was investigated in 2D and 3D co-culture models by videomicroscopy and automated image analysis. Results Meso-CAFs show a normal diploid genotype without gene copy number aberrations typical for PM cells. They express CAF markers and lack PM marker expression. Their proteome and secretome profiles clearly differ from normal lung fibroblasts with particularly strong differences in actively secreted proteins. The presence of Meso-CAFs in co-culture resulted in significantly increased proliferation and migration of PM cells. A similar effect on PM cell growth and migration was induced by Meso-CAF-conditioned medium. Inhibition of c-Met with crizotinib, PI3K with LY-2940002 or WNT signaling with WNT-C59 significantly impaired the Meso-CAF-mediated growth stimulation of PM cells in co-culture at concentrations not affecting the PM cells alone. Meso-CAFs did not provide protection of PM cells against cisplatin but showed significant protection against the EGFR inhibitor erlotinib. Conclusions Our study provides the first characterization of human patient-derived Meso-CAFs and demonstrates a strong impact of Meso-CAFs on PM cell growth and migration, two key characteristics of PM aggressiveness, indicating a major role of Meso-CAFs in driving PM progression. Moreover, we identify signaling pathways required for Meso-CAF-mediated growth stimulation. These data could be relevant for novel therapeutic strategies against PM.

Exploration of cancer associated fibroblasts phenotypes in the tumor microenvironment of classical and pleomorphic Invasive Lobular Carcinoma

“…CAFs are heterogenous and so care has to be taken in selecting the markers to be used for particular tumor type. For instance, in a study by Ries et al ( 45 ) on Pleural mesotheliomas, FAP which is a CAF marker was also shown to be expressed from mesothelioma cells in addition to the fibroblasts. Hence, they propose that FAP is not a good marker to characterize CAFs in Pleural mesotheliomas.…”

“…The role of CAF in metastasis is well established, when analyzed as a global population ( 40 ) and they serve different functions in tumor biology such as proliferation, metastasis and drug resistance ( 41 – 43 ). CAFs are heterogenous and express different markers either individually or in co-expression and the composition also varies across different tumor types ( 44 , 45 )]. CAFs originate from various types of cells, including resident fibroblasts, bone marrow-derived ancestors, or epithelial carcinoma cells that undergo epithelial-mesenchymal transition ( 17 , 46 ).…”

Machine learning‐based establishment and validation of age‐related patterns for predicting prognosis in non‐small cell lung cancer within the context of the tumor microenvironment

“…Combining the analysis of immune cell components in lung cancer microenvironment, we could clearly observe that patients in cluster 2 had the higher proportion of fibroblasts. As is well known, the special kind of fibroblasts around the tumor is called Cancer‐associated fibroblasts (CAFs), as the main components in TME 59 . Many studied showed that CAFs not only play key roles in tumor proliferation and invasion, but also influence the efficacy of immunotherapy 60 .…”

“…As is well known, the special kind of fibroblasts around the tumor is called Cancer-associated fibroblasts (CAFs), as the main components in TME. 59 Many studied showed that CAFs not only play key roles in tumor proliferation and invasion, but also influence the efficacy of immunotherapy. 60 In contrast, cluster 1 had a higher MeTIL score and a lower EMT score, which suggests that patients in cluster 1 would benefit the most from immunotherapy.…”

Targeting endogenous fatty acid synthesis stimulates the migration of ovarian cancer cells to adipocytes and promotes the transport of fatty acids from adipocytes to cancer cells

“…High-level transgene expression of fluorescent proteins was achieved by the retroviral transduction of a cDNA for red mCherry, as previously described ( 32 , 33 ). Briefly, 2×10 6 293T cells (Takara Bio USA, Inc.) maintained in DMEM plus 10% FCS were transfected in T25 cell culture flasks (Thermo Fisher Scientific, Inc.) by calcium phosphate co-precipitation with 5 μ g of the Moloney murine leukemia virus (MMLV)-derived retroviral expression plasmid pQCXIP (Takara Bio USA, Inc.) containing sequences for puromycin resistance and mCherry, and with 3.75 μ g p-gag-pol-gpt ( 34 ) and 1.25 μ g pVSV-G (Takara Bio USA, Inc.) as helper plasmids.…”