Project description:Triple-negative breast cancer represents approximately 15–20% of all reported breast cancer cases, and is characterized by a shorter survival time and higher mortality rates compared to other breast cancer sub-types. Tumor microenvironment (TME) refers to the internal and external environment of tumor tissue. Increasing evidence indicates that a tumor’s microenvironment is tightly associated with the immunological surveillance and defense during the development of breast cancer. Although oncology studies employing digital dissection methodologies have provided some insight on the biological features of TME, the development of methods to investigate the cellular composition of the tumor microenvironment remain an important research priority. In this study, we extracted whole transcriptome from 30 Triple-negative breast cancer (TNBC) patients and then used bioinformatics approaches to characterize cell type content in tumor tissue compared with para-cancerous tissue. We identified 4 types of enriched immune cells and 6 types of downregulated immune cells in the tumor tissue samples. After comprehensive bioinformatics analyses, we developed an ‘immune infiltration score’ (IIS) to quantitatively model immune cell infiltration in TNBC. To demonstrate the utility of the IIS, we used 2 independent datasets for validation. We found that patients with a higher IIS showing a longer progression-free survival time and significantly better prognosis than those with a lower IIS value. In sum, we explored the immune infiltration landscape in 30 TNBC patients and provided a novel and reliable biomarker IIS to evaluate the progression-free survival and prognosis in the TNBC patients.
Project description:We hypothesized that the immune microenvironment of the bone marrow influences the progression of myeloma outgrowth in the 5TGM1 transfer model of multiple myeloma. Therefore we sorted bone marrow T, NK, and non-hematopoietic stromal cells from control and tumor-bearing C57Bl/6 mice.
Project description:With the advent of cancer immunotherapy, intense investigation has been focused on tumor-infiltrating immune cells. With only a fraction of patients responding to these new therapies, a better understanding of all elements of the tumor microenvironment (TME) that may influence therapeutic outcome is needed. Stromal elements of the TME, chiefly fibroblasts, have emerged as potential contributors to tumor progression and most recently resistance to immunotherapy, but their precise composition and clinical relevance remain incompletely understood. Here we use single-cell transcriptomics to chart the fibroblastic landscape during pancreatic ductal adenocarcinoma (PDAC) progression in animal models, identifying two healthy tissue fibroblast subsets that co-evolve along individual trajectories into four subsets of carcinoma-associated fibroblasts (CAFs).
Project description:Reciprocal interactions between breast cancer cells and the tumor microenvironment are important for cancer progression and metastasis. We report here that the deletion or inhibition of sphingosine kinase 2 (SphK2), which produces sphingosine-1-phosphate (S1P), markedly suppresses syngeneic breast tumor growth and lung metastasis in mice by creating a hostile microenvironment for tumor growth and invasion. SphK2 deficiency decreased S1P and concomitantly increased ceramides, including C16-ceramide, in stromal fibroblasts. Ceramide accumulation suppressed activation of cancer-associated fibroblasts (CAFs) by upregulating stromal p53, which restrained production of tumor-promoting factors to reprogram the tumor microenvironment and restrict breast cancer establishment. Ablation of p53 in SphK2-deficient fibroblasts reversed these effects, enabled CAF activation and promoted tumor growth and invasion. These data uncovered a novel role of SphK2 in regulating non-cell autonomous functions of p53 in stromal fibroblasts and their transition to tumor-promoting CAFs, paving the way for the development of a strategy to target the tumor microenvironment and enhance therapeutic efficacy.
Project description:Cancer development and progression depend on tumor cell intrinsic factors, the tumor microenvironment and host characteristics. Despite the identification of the plasticity of adipocytes, the primary breast stromal cells, both in physiology and cancer, we lack a complete understanding of mechanisms that regulate adipocyte-tumor cell crosstalk. Here we dissected the breast cancer crosstalk with adipocytes and studied relevant molecules. We identified that the ability of breast cancer cells to dedifferentiate adipocytes is intrinsic subtype-dependent, with all breast cancer subtypes, except for HER2+ER+ subtype, capable of inducing this phenomenon. Crosstalk between breast cancer cells and adipocytes in vitro increased cancer stem-like features and recruitment of pro-tumorigenic immune cells, through chemokine production. Serum amyloid A1 (SAA1) was in vitro identified as a regulator of the adipocyte dedifferentiation program in triple-negative breast cancer (TNBC) through CD36 and P2XR7 signaling. In human TNBCs, SAA1 expression was associated with CAA infiltration, inflammation, stimulated lipolysis, stem-like properties and distinct tumor immune microenvironment. Our findings provide evidence that interaction between tumor cells and adipocytes through SAA1 release is relevant to the aggressiveness of TNBC, potentially supporting its targeting.
Project description:Stromal cells within the tumor microenvironment are essential for tumor progression and metastasis. Yet surprisingly little is known about the factors that drive the transcriptional reprogramming of stromal cells within tumors. We report that the transcriptional regulator Heat-Shock Factor 1 (HSF1) is activated in cancer-associated fibroblasts (CAFs) and is a potent enabler of malignancy. In CAFs, HSF1 drives a transcriptional program that complements, yet is completely different from, the program it drives in adjacent cancer cells. This CAF program is uniquely structured to support the malignant potential of cancer cells in a non-cell-autonomous way and involves two central stromal signaling moleculesM-bM-^@M-^TTGFM-NM-2 and stromal-derived factor 1 (SDF1). As clinical confirmation, in early stage breast and lung cancer high stromal HSF1 activation is strongly associated with poor patient outcome. Thus, cancers co-opt the ancient, multifaceted survival functions of HSF1 to orchestrate malignant progression in unexpected ways that have far-reaching therapeutic implications. Gene expression data We used microarrays to examine the HSF1-dependent effect of co-culture on gene expression in cancer cells and fibroblasts. D2A1 mouse breast cancer cells were co-cultured with WT or Hsf1 null MEFs for 72h, afterwhich the two cell types were separated from each other by FACS and analyzed. Each cell type was also grown separately, as control.
Project description:Primary tumor growth induces host tissue responses that are believed to support and promote tumor progression. Identification of the molecular characteristics of the tumor microenvironment and elucidation of its crosstalk with tumor cells may therefore be crucial for improving our understanding of the processes implicated in cancer progression, identifying potential therapeutic targets, and uncovering stromal gene expression signatures that may predict clinical outcome. A key issue to resolve, therefore, is whether the stromal response to tumor growth is largely a generic phenomenon, irrespective of the tumor type, or whether the response reflects tumor-specific properties. To address similarity or distinction of stromal gene expression changes during cancer progression, oligonucleotide-based Affymetrix microarray technology was used to compare the transcriptomes of laser-microdissected stromal cells derived from invasive human breast and prostate carcinoma. Invasive breast and prostate cancer-associated stroma was observed to display distinct transcriptomes, with a limited number of shared genes. Interestingly, both breast and prostate tumor-specific dysregulated stromal genes were observed to cluster breast and prostate cancer patients, respectively, into two distinct groups with statistically different clinical outcomes. By contrast, a gene signature that was common to the reactive stroma of both tumor types did not have survival predictive value. Univariate Cox analysis identified genes whose expression level was most strongly associated with patient survival. Taken together, these observations suggest that the tumor microenvironment displays distinct features according to the tumor type that provides survival-predictive value. 6 samples of stroma surrounding invasive breast primary tumors; 6 matched samples of normal stroma. 6 samples of stroma surrounding invasive prostate primary tumors; 6 matched samples of normal stroma.
Project description:Here we describe the development of a robust method for RNA extraction and exome-capture RNA-sequencing of laser-capture microdissected (LCM) tumor cells (TC) and stromal immune cells (TIL) based on their morphology. We applied this method on seven tumor specimens and microbiopsies of triple-negative breast cancers (TNBC) stored in FFPE blocks. Together, we showed that combining LCM and RNA-sequencing on archived FFPE blocks is feasible and allows spatial transcriptional characterization of the tumor microenvironment.
Project description:Metastasis is a multistage process that requires cancer cells to escape from the primary tumor, survive in the circulation, seed at distant sites and colonize these foreign tissue environments. Each of these processes involves rate-limiting steps that are influenced by stromal cells of the tumor microenvironment. While the tumor microenvironment has emerged as a major regulator of cancer progression in other organ sites, our knowledge of the brain metastatic microenvironment is currently very limited. Thus, we aim to dissect signatures of tumor-stroma interactions in brain metastasis in order to identify factors that regulate the homing, seeding and outgrowth of cancer cells in this highly specialized microenvironment. We took advantage of an experimental metastasis model in which variants of the human breast cancer line MDA-MB-231 home to the brain in xenografted animals. To simultaneously capture gene expression changes in the tumor and stromal compartment, we used a dual species-specific microarray platform, the HuMuProtIn array, to discriminate between differentially expressed protease or protease inhibitor genes of human (tumor) or murine (stromal) origin. RNA was isolated from early and late brain, bone and lung metastases from xenograft models of breast metastasis. RNA was also isolated from non-tumor-burdened mouse brain, bone and lung as normal tissue controls. RNA from tissue homing cell lines was isolated in vitro to serve as a control for the human-derived RNA. Samples were collected from 24 total tumor-burdened mice, with 3 replicates for each condition and control. A total of 36 samples are included here.
Project description:Stromal cells within the tumor microenvironment are essential for tumor progression and metastasis. Yet surprisingly little is known about the factors that drive the transcriptional reprogramming of stromal cells within tumors. We report that the transcriptional regulator Heat-Shock Factor 1 (HSF1) is activated in cancer-associated fibroblasts (CAFs) and is a potent enabler of malignancy. In CAFs, HSF1 drives a transcriptional program that complements, yet is completely different from, the program it drives in adjacent cancer cells. This CAF program is uniquely structured to support the malignant potential of cancer cells in a non-cell-autonomous way and involves two central stromal signaling molecules—TGFβ and stromal-derived factor 1 (SDF1). As clinical confirmation, in early stage breast and lung cancer high stromal HSF1 activation is strongly associated with poor patient outcome. Thus, cancers co-opt the ancient, multifaceted survival functions of HSF1 to orchestrate malignant progression in unexpected ways that have far-reaching therapeutic implications. Gene expression data