Project description:Gene expression changes in metastasis associated macrophage (MAM) with control and FLT1 inhibitory antibody (MF1) were compared using FACS sorted cells from mice bearing pulmonary metastasis of breast tumor cells treated with Ctrl and MF1 antibody A six chip study using total RNA recovered from metastasis associated macrophages from three separate mice treated with FLT1 inhibitory antibody (MF1) and three separate mice treated with control antibody. Each chip measures the expression level of 42586 genes.
Project description:Gene expression changes in metastasis associated macrophage (MAM) FACS sorted cells from mice bearing pulmonary metastasis of breast tumor cells were compared with lung and spleen resident macrophages sorted from healthy mice using same sorting protocol. A six chip study using total RNA recovered from metastasis associated macrophages from three individual mice and lungs and spleens all from three individual mice. Each chip measures the expression level of 42586 genes.
Project description:Colorectal cancer is a major cause of mortality worldwide. Most patients develop colorectal liver metastases (CLM), and for such patients hepatectomy combined with chemotherapy may be curative. Nevertheless, in the era of precision medicine there is a critical need of prognostic markers to cope with the heterogeneity of CLM patients. Tumor-associated macrophages (TAMs) pave the way to tissue invasion and intravasation providing a nurturing microenvironment formetastases. The quantification of immune landscape of tumors has provided novel prognostic indicators of cancer progression, and the quantification of TAMs might explain the heterogeneity of CLM patients. Here, we will investigate the development of a new diagnostic tool based on TAMs with the aim to define the causative role of TAMs in CLM patients. This will open new clinical scenarios both for the diagnosis, therapy and prognosis, leading to the refinement of the therapeutic output in a personalized medicine perspective.
Project description:Clinical and experimental evidence indicates that tumor-associated macrophages (TAMs) promote malignant progression. In breast cancer, TAMs enhance tumor angiogenesis, tumor cell invasion, matrix remodeling, and immune suppression against the tumor. In this study, we examined late-stage mammary tumors from a transgenic mouse model of breast cancer. We used flow cytometry under conditions that minimized gene expression changes to isolate a rigorously defined TAM population previously shown to be associated with invasive carcinoma cells. The gene expression signature of this population was compared with a similar population derived from spleens of non-tumor-bearing mice using high-density oligonucleotide arrays. Using stringent selection criteria, transcript abundance of 460 genes was shown to be differentially regulated between the two populations. Bioinformatic analyses of known functions of these genes indicated that formerly ascribed TAM functions, including suppression of immune activation and matrix remodeling, as well as multiple mediators of tumor angiogenesis, were elevated in TAMs. Further bioinformatic analyses confirmed that a pure and valid TAM gene expression signature in mouse tumors could be used to assess expression of TAMs in human breast cancer. The data derived from these more physiologically relevant autochthonous tumors compared with previous studies in tumor xenografts suggest tactics by which TAMs may regulate tumor angiogenesis and thus provide a basis for exploring other transcriptional mediators of TAM trophic functions within the tumor microenvironment. Tumor-associated macrophages from late-stage mouse mammary tumors compared to splenic macrophages from non-tumor-bearing littermate controls. 4 biological replicates of each population were compared via gene expression arrays.
Project description:Macrophages have been implicated in breast cancer progression and metastasis, but relatively little is known about the genes and pathways that are involved. Using a conditional allele of Ets2 in the mouse, we have identified Ets2 as a critical gene in tumor associated macrophages (TAMs) that specifically promotes mammary tumor metastasis. Loss of Ets2 in TAMs decreased the frequency and size of lung metastases without impacting primary tumor burden. Expression profiling of isolated tumor macrophages established that Ets2 deficiency resulted in the de-repression of a defined set of anti-angiogenic genes. Activation of this transcriptional program correlated with decreased angiogenesis in metastatic tumors and decreased metastatic growth. Comparison of this Ets2-specific TAM expression profile with human breast cancer profiles revealed a macrophage gene expression signature that could predict overall survival of estrogen receptor negative patients. In summary, we have identified a critical factor, Ets2, in TAMs that represses a transcriptional program to promote the growth of mammary tumor metastases in the lung. Breast TAMs were isolated from early-stage PyMT-induced mammary tumors expressing Ets2 and also from the tumors with Ets2-deficient TAMs. Since macrophages have also been implicated in normal mammary gland remodeling, normal remeodeling macrophages were also purified from females expressing Ets2 and the ones where Ets2 is deleted in the macrophages. One RNA sample was extracted from each genetic group for gene-expression profiling.