Project description:Since bone metastatic breast cancer is an incurable disease, causing significant morbidity and mortality, understanding of the underlying molecular mechanisms would be highly valuable. Here, we describe in vitro and in vivo evidence for the importance of serine biosynthesis in the metastasis of breast cancer to bone. We first characterized the bone metastatic propensity of the MDA-MB-231(SA) cell line variant as compared to the parental MDA-MB-231 cells by radiographic and histological observations in the inoculated mice. Genome-wide gene expression profiling of this isogenic cell line pair revealed that all the three genes involved in the L-serine biosynthesis pathway, phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH) were upregulated in the highly metastatic variant. This pathway is the primary endogenous source for L-serine in mammalian tissues. Consistently, we observed that the proliferation of MDA-MB-231(SA) cells in serine-free conditions was dependent on PSAT1 expression. In addition, we observed that L-serine is essential for the formation of bone resorbing human osteoclasts and may thus contribute to the vicious cycle of osteolytic bone metastasis. High expression of PHGDH and PSAT1 in primary breast cancer was significantly associated with decreased relapse-free and overall survival of patients and malignant phenotypic features of breast cancer. In conclusion, high expression of serine biosynthesis genes in metastatic breast cancer cells and the stimulating effect of L-serine on osteoclastogenesis and cancer cell proliferation indicate a functionally critical role for serine biosynthesis in bone metastatic breast cancer and thereby an opportunity for targeted therapeutic interventions. Parental MDA-MB-231 cells and MDA-MB-231(SA) cells were cultured in cell culture flasks. RNA was isolated in order to compare the gene expression profiles of these cell variants. Total of two samples. No replicates.
Project description:To provide preliminary insights into metabolic and lipidomic characteristics in radioresistant triple-negative breast cancer (TNBC) cells and suggest potential therapeutic targets, we performed a comprehensive metabolic and lipidomic profiling of radioresistant MDA-MB-231 (MDA-MB-231/RR) TNBC cells and their parental cells using gas chromatography-mass spectrometry and nano electrospray ionization-mass spectrometry, followed by multivariate statistical analysis. Buthionine sulfoximine (BSO) and radiation were co-treated to radioresistant TNBC cells. The level of glutathione (GSH) was significantly increased, and the levels of GSH synthesis-related metabolites, such as cysteine, glycine, and glutamine were also increased in MDA-MB-231/RR cells. In contrast, the level of lactic acid was significantly reduced. In addition, reactive oxygen species (ROS) level was decreased in MDA-MB-231/RR cells. In the lipidomic profiles of MDA-MB-231/RR cells, the levels of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were significantly increased, whereas those of most of the phosphatidylinositol species were significantly decreased. BSO sensitized MDA-MB-231/RR cells to radiotherapy, which resulted in decreased GSH level and increased ROS level and apoptosis. Radioresistant TNBC cells showed distinct metabolic and lipidomic characteristics compared to their parental cells. We suggested activated GSH, PC, and PE biosynthesis pathways as potential targets for treating radioresistant TNBC cells. Particularly, enhanced radiosensitivity was achieved by inhibition of GSH biosynthesis in MDA-MB-231/RR cells.
Project description:Identification of genes that are involved in self-seeding by comparing gene expression profiles between parental MDA-MB-231 cells and seeder cells (MDA-231-S1a and S1b) 2 replicates from each sample (parental MDA-MB-231, MDA-MB-231 S1a and MDA-MB-231 S1b) were analyzed
Project description:The project profiled the expression patterns in hypoxia induced secretomes between MDA-MB-231 parental and MDA-MB-231 Bone Tropic (BT) breast cancer cell lines which have been previously generated by Massague and colleagues (Kang et al. Cancer Cell 2003).
Project description:To investigate the function of Neuropilin-1 (NRP-1) in breast cancer MDA-MB-231 cells. CRISPR-Cas9 gene editing was used to knockout (KO) the NRP-1 gene in MDA-MB-231 human triple-negative breast cancer cells. Differentially expressed genes (DEGs) were determined in NRP-1 KO and parental MDA-MB-231 cells using whole transcriptome next-generation sequencing.
Project description:Since bone metastatic breast cancer is an incurable disease, causing significant morbidity and mortality, understanding of the underlying molecular mechanisms would be highly valuable. Here, we describe in vitro and in vivo evidence for the importance of serine biosynthesis in the metastasis of breast cancer to bone. We first characterized the bone metastatic propensity of the MDA-MB-231(SA) cell line variant as compared to the parental MDA-MB-231 cells by radiographic and histological observations in the inoculated mice. Genome-wide gene expression profiling of this isogenic cell line pair revealed that all the three genes involved in the L-serine biosynthesis pathway, phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH) were upregulated in the highly metastatic variant. This pathway is the primary endogenous source for L-serine in mammalian tissues. Consistently, we observed that the proliferation of MDA-MB-231(SA) cells in serine-free conditions was dependent on PSAT1 expression. In addition, we observed that L-serine is essential for the formation of bone resorbing human osteoclasts and may thus contribute to the vicious cycle of osteolytic bone metastasis. High expression of PHGDH and PSAT1 in primary breast cancer was significantly associated with decreased relapse-free and overall survival of patients and malignant phenotypic features of breast cancer. In conclusion, high expression of serine biosynthesis genes in metastatic breast cancer cells and the stimulating effect of L-serine on osteoclastogenesis and cancer cell proliferation indicate a functionally critical role for serine biosynthesis in bone metastatic breast cancer and thereby an opportunity for targeted therapeutic interventions.