Project description:Background: In previous work we discovered that T lymphocytes play a prominent role in the rise of brain metastases of ER-negative breast cancers. In the present study we explored expressional changes due to T cell contact associated with penetration through the BBB for breast cancer cell lines derived from cancers with various affinities for brain. Methods: Differential expression of proteins was identified by comparing the proteomes of the breast cancer cells before and after co-culture with T cells by using liquid chromatography-mass spectrometry (LC-MS). siRNA was used to silence protein expression in the tumor cells and the artificial BBB model was employed to study the effects on passage of the breast carcinoma cell lines. Results: Mass spectrometry-based proteomics revealed significant alterations in the expression of 35 proteins by the breast cancer cell lines upon T cell contact. Among the proteins is coronin-1A, a protein related to cell motility. Knockdown of CORO1A in the breast cancer cells reduced their ability to cross the artificial BBB to 60%. The effects were significantly less for the cell line derived from breast cancer with affinity for brain. The expression of coronin-1A was confirmed by immunohistochemistry and RT-PCR of 52 breast cancer samples of patients with metastasized breast cancers, with and without brain locations. Lastly, CORO1A upregulation was validated in a publicly available mRNA expression database from 204 primary breast cancers with known metastatic sites. Conclusions: We conclude that T lymphocytes trigger cancer cells to express proteins including coronin-1A thereby facilitating their passage through an in vitro BBB. In addition, a prominent role of coronin-1A in the formation of cerebral metastases in breast cancer patients is strongly suggestive by its upregulation in tissue samples of breast cancer patients with brain metastases.
Project description:Metastatic lesions are typically not found until patients self-report symptoms or they become radiologically evident. We have developed an engineered metastatic niche (scaffold) that recruits aggressive tumor cells prior to their colonization in other organs. The engineered niche can be monitored for dynamic gene expression, and changes at this site are analogous to those in a native metastatic site (lung) for triple negative breast cancer (4T1 cells). We were able to develop a 10-gene signature from the scaffold that accurately monitors disease progression and recurrence or resistance to resection therapy. This data set acts to dissect the heterogeneity of the cell populations in the engineered and native metastatic niche and identify the cell types that contribute to the success of the signature.
Project description:Breast cancers enriched for the triple negative breast cancer phenotype with extensive clinico-pathological features were profiled to establish their comprehensive transcriptional profiles
Project description:The goal of the experiment was to demonstrate if the overexpression of human-Prune-1 in Triple Negative breast cancer cells induces M2-polarization of macrophages in vitro. For this purpose, murine primary cells from breast tumor developed by Genetically Engineered Mouse Models (GEMMs) of TNBC (i.e., MMTV-Wnt1) and metastatic TNBC overexpressing both human Prune-1 and Wnt1 in mammary gland (i.e., MMTV-Prune-1/Wnt1) were obtained. Conditioned media were collected from these primary cells (1x106 cells) after 24 hours. Murine macrophages (J774A.1 and Raw264.7; 1x106) were starved for six hours and then grown for 48 hours in those conditioned media collected from MMTV-Wnt1 and MMTV-Prune-1/Wnt1 cells. Untreated macrophages were used as negative control for the experiment.
