Project description:How stroma communicates with cancer to influence treatment response is poorly understood. We show that stromal fibroblasts protect breast cancer (BrCa) against radiation and chemotherapy through an exosome-mediated anti-viral pathway and NOTCH3. Stroma increases RAB27B and transfers exosomes to BrCa. RNA within exosomes, comprised largely of non-coding transcripts and transposable elements, stimulates the pattern recognition receptor RIG-I through a 5M-bM-^@M-^Y-triphosphate motif to activate STAT1. BrCa NOTCH3 is activated in parallel by stromal JAG1 and cooperates with STAT1 to enhance transcriptional responses of NOTCH target genes and to expand therapy resistant tumor-initiating cells. Computational modeling using primary human and mouse BrCa supports the interaction of anti-viral/NOTCH3 pathways in controlling NOTCH target genes and treatment resistance, particularly in basal subtype tumors. Gamma secretase inhibitors reverse stromal protection and abrogate radiation resistance in vivo. Thus, stroma orchestrates an intricate cross-talk with BrCa by utilizing exosomes to coax anti-viral signaling that expands therapy resistant cells through druggable pathways. RNA profile of ceullar RNA and exosome of co-culture of breast caner cell line 1833 and stroma cell line MRC5.
Project description:High-grade serous ovarian cancer (HG-SOC), characterized by very frequent mutations in TP53 gene, is a highly lethal cancer and is refractory to therapeutic strategies. In HG-SOC, the reciprocal signal exchange between tumor cells and various types of stromal elements from the tumor microenvironment (TME) shapes the malignant phenotype and limits drug efficacy, suggesting that blunting the HG-SOC/TME interplay may improve the anti-tumor therapy response rate. Here, we unveil how the endothelin-1 (ET-1)/ET-1 receptors (ET-1R) signaling, instructing the mutual inter-regulation between HG-SOC cells, endothelial cells (EC) and activated fibroblasts, regulates malignant progression and PARP inhibitor (PARPi) response. Mechanistically, ET-1 axis, mimicking hypoxia, enhances the mutant p53 (mutp53)/YAP/hypoxia inducible factor-1α (HIF-1α) transcriptional cooperation, that culminates with the release of diffusible mediators, as ET-1 and VEGF, that charting a bilateral HG-SOC/stroma signaling route, regulate the acquisition of pro-metastatic traits and PARPi response. Concurrently, our study establishes that ET-1 signaling its instrumental for the activation of p53/YAP/HIF-1α transcriptional machinery within the EC and the activated fibroblasts, shaping their behaviour and secretome. The dual ET-1R antagonist macitentan, dismantling the ET-1R-mediated mutp53/YAP/HIF-1α network, interferes with the ET-1-guided tumor/stroma communication. In vivo macitentan, sensitizing HG-SOC patient-derived xenografts (PDX) to the PARPi, Olaparib, reduces their metastatic potential. Clinically relevant, ETAR/YAP/HIF-1α gene signature correlates with a dismal prognosis in HG-SOC patients. Our findings recognize in the networking between ET-1R and YAP/mutp53/HIF-1α a tumor/TME shared escaping strategy from DNA damaging agents and support the use of ET-1R antagonists in combinatorial treatments with PARPi for HG-SOC patients.
Project description:How stroma communicates with cancer to influence treatment response is poorly understood. We show that stromal fibroblasts protect breast cancer (BrCa) against radiation and chemotherapy through an exosome-mediated anti-viral pathway and NOTCH3. Stroma increases RAB27B and transfers exosomes to BrCa. RNA within exosomes, comprised largely of non-coding transcripts and transposable elements, stimulates the pattern recognition receptor RIG-I through a 5’-triphosphate motif to activate STAT1. BrCa NOTCH3 is activated in parallel by stromal JAG1 and cooperates with STAT1 to enhance transcriptional responses of NOTCH target genes and to expand therapy resistant tumor-initiating cells. Computational modeling using primary human and mouse BrCa supports the interaction of anti-viral/NOTCH3 pathways in controlling NOTCH target genes and treatment resistance, particularly in basal subtype tumors. Gamma secretase inhibitors reverse stromal protection and abrogate radiation resistance in vivo. Thus, stroma orchestrates an intricate cross-talk with BrCa by utilizing exosomes to coax anti-viral signaling that expands therapy resistant cells through druggable pathways.
Project description:Primary astrocytomas of high histopathological grade (HG-astrocytomas) are largely restricted to older patients and are almost invariably fatal despite multimodal therapy. Here, we show that the young brain has an endogenous defense mechanisms against HG-astrocytomas. Neural precursor cells (NPCs) migrate to HG-astrocytomas, reduce glioma expansion and prolong survival by releasing a group of fatty-acid ethanolamides that have agonistic activity on the vanilloid receptor (transient receptor potential vanilloid subfamily member-1; TRPV1). TRPV1 expression is much higher in HG-astrocytomas than in the tumor-free brain and TRPV1 stimulation triggers tumor cell-death via the activating transcription factor-3 (ATF3) controlled branch of the ER-stress pathway. The anti-tumourigenic response of NPCs is lost with aging. NPC-mediated tumor suppression can be mimicked in the old brain by systemic administration of the synthetic vanilloid Arvanil, indicating that TRPV1 agonists hold potential as new HG-astrocytoma therapeutics.
Project description:Mathematical modeling of immune modulation by glucocorticoids
Konstantin Yakimchuk
https://doi.org/10.1016/j.biosystems.2019.104066
Abstract
The cellular and molecular mechanisms of immunomodulatory actions of glucocorticoids (GC) remain to be identified. Using our experimental findings, a mathematical model based on a system of ordinary differential equations for characterization of the regulation of anti-tumor immune activity by the both direct and indirect GC effects was generated to study the effects of GC treatment on effector CD8+ T cells, GC-generated tolerogenic dendritic cells (DC), regulatory T cells and the growth of lymphoma cells. In addition, we compared the data from in vivo and in silico experiments. The mathematical simulations indicated that treatment with GCs may suppress anti-tumor immune response in a dose-dependent manner. The model simulations were in line with earlier experimental observations of inhibitory effects of GCs on T and NK cells and DCs. The results of this study might be useful for predicting clinical outcomes in patients receiving GC therapy.