Project description:Integrative analysis of primary estrogen receptor-positive (ER+) breast cancer, triple-negative breast cancer (TNBC), and metaplastic breast cancer (MBC) tumors using Starfysh.
Project description:Deciphering breast cancer treatment resistance remains hindered by the lack of models that can successfully capture the four-dimensional dynamics of the tumor microenvironment. Here, we show that microextrusion bioprinting can reproducibly produce distinct cancer and stromal compartments integrating cells relevant to human pathology. Our findings unveil the functional maturation of this millimeter-sized model, showcasing the development of a hypoxic cancer core and an increased surface proliferation. Maturation was also driven by the presence of cancer-associated fibroblasts (CAF) that induced elevated microvascular-like structures complexity. Such modulation was concomitant to extracellular matrix remodeling, with high levels of collagen and matricellular proteins deposition by CAF, simultaneously increasing tumor stiffness and recapitulating breast cancer fibrotic development. Importantly, our bioprinted model faithfully reproduced response to treatment, further modulated by CAF. Notably, CAF played a protective role for cancer cells against radiotherapy, facilitating increased paracrine communications. This model holds promise as a platform to evaluate microenvironment targeting drugs in a human pathology relevant context, that could lead to significant improvements for patient care.
Project description:Intratumor heterogeneity is one of the hallmarks of cancers, including breast cancers. We performed spatial transcriptomics to profile heterogeneous cell populations within ER+ breast cancers as well as to determine their importance for estrogen-dependent tumor growth. Our analysis has revealed the key functional compartments for developing targeted therapeutic strategies against ER+ breast cancers.
Project description:The mouse uterine microenvironment at pregnancy D7.5 was investigated by Visium spatial transcriptome. Ten distinct uterine microenvironments were identified with diverse biological functions, different endocrine regulations and intensive interactions. The single cell RNA-seq of D7.5 mouse uterus has been intergrated with the spatial visium results and predicted the presence of mutiple types of cells in each microenvironment.
Project description:Breast cancer is the most common cancer in females, affecting one in every eight women and accounting for the majority of cancer-related deaths in women worldwide. Germline mutations in the BRCA1 and BRCA2 genes are significant risk factors for specific subtypes of breast cancer. BRCA1 mutations are associated with basal-like breast cancers, whereas BRCA2 mutations are associated with luminal-like disease. Defects in mammary epithelial cell differentiation have been previously recognized in germline BRCA1/2 mutation carriers even before cancer incidence. However, the underlying mechanism is largely unknown. Here, we employ spatial transcriptomics to investigate defects in mammary epithelial cell differentiation accompanied by distinct microenvironmental alterations in preneoplastic breast tissues from BRCA1/2 mutation carriers and normal breast tissues from non-carrier controls. We uncovered spatially defined receptor-ligand interactions in these tissues for the investigation of autocrine and paracrine signaling. We discovered that β1-integrin-mediated autocrine signaling in BRCA2-deficient mammary epithelial cells may differ from BRCA1-deficient mammary epithelial cells. In addition, we found that the epithelial-to-stromal paracrine signaling in the breast tissues of BRCA1/2 mutation carriers is greater than in control tissues. More integrin-ligand pairs were differentially correlated in BRCA1/2-mutant breast tissues than non-carrier breast tissues with more integrin receptor-expressing stromal cells. Implications: These results suggest alterations in the communication between mammary epithelial cells and the microenvironment in BRCA1 and BRCA2 mutation carriers, laying the foundation for designing innovative breast cancer chemo-prevention strategies for high-risk patients.
Project description:The breast tumor microenvironment plays an active role in tumorigenesis. Molecular alterations, including epigenetic modifications to DNA, and changes in RNA and protein expression have been identified in tumor-associated stroma; however, there is considerable debate as to whether the stroma is characterized by genomic instability or whether detection of chromosomal alterations in the breast stroma is a reflection of technological artifact rather than the true genomic content of the tumor microenvironment. Methods: Surgically-removed breast stroma specimens from 112 women undergoing reductive mammoplasty (n=15), prophylactic mastectomy (N=6) or mastectomy for a diagnosis of breast disease (n=92) were frozen in optimal cutting temperature medium. Allelic imbalance (AI) analysis was performed in 484 stromal specimens from 98 women using a panel of 52 microsatellite markers; SNP data was generated from a subset of 86 stromal specimens using 250K SNP arrays (Affymetrix). Copy number alterations were identified using Partek Genomics Suite. Results: AI was not detected in 92% (444/484) of stroma specimens. When compared to previously generated AI data from 77 formalin-fixed, paraffin-embedded stroma specimens (Ellsworth et al., Ann Surg Oncol 2004), 32 (42%) of which harbored at least one detectable AI event, the frequency of AI in the FFPE specimens (4.62%) was significantly higher (P<0.0001) than that found in frozen specimens (0.45%). Of the stroma specimens assayed using SNP arrays 95% (82/86) had no detectable alterations and the 11 copy number changes were small and not shared between specimens. Conclusions: The data presented here support a model in which the tumor microenvironment is genetically stable. The direct comparison of copy number alterations between FFPE and frozen research-grade specimens using identical methodologies suggests that past reports of significant AI in breast stroma, both adjacent to and distant from the tumor, reflects artifact in the archival specimens caused by formalin-fixation, paraffin-embedding and tissue storage. 250K STY data was generated for 86 breast stromal specimens. The tissue specimens were analyzed by paired analysis to the SNP data from matched genomic (blood) DNAs
Project description:Understanding the spatial organization of the bone marrow (BM) microenvironment at single cell resolution and the niche specific transcriptional regulatory programs remains a challenge. Using formalin-fixed paraffin-embedded (FFPE) samples from our recently described MIcγ1 multiple myeloma (MM) mouse model (Larrayoz et al, Nat Med. 2023), we performed spatial transcriptional profiling of healthy and multiple myeloma BM using the Visium Spatial Gene Expression analysis (10x Genomics). A custom data-analysis framework that combines spatial with single-cell transcriptomic profiles allowed us to identify cell type composition and establish specific cell relations within the bone marrow. As a result, we defined the spatial distribution of transcriptionally heterogenous MM plasma cell (MM-PC) groups. Furthermore, we spatially defined transcriptional programs involved in the pathogenesis of MM within the BM microenvironment that were associated with MM-PC density gradient, such as the spatial location of T cells with effector and exhausted phenotypes. Application of spatial transcriptomics to FFPE human BM biopsies with varying degrees of PC infiltration validated findings from our murine model. The application of spatial transcriptomics to fully mineralized tissues provides a comprehensive spatial overview of the BM microenvironment allowing the identification of deregulated mechanism involved in the pathogenesis of diseases such as MM.