Project description:Screening of miRNA mimics resulted in differential motility capacity. To discover novel miRNA motility regulators, gene expression of breast cancer cells transfected with miRNA mimics were compared.
Project description:Metastasis accounts for almost 90% of breast cancer-related fatalities, making it frequent malignancy and the main reason of tumor mortality globally among women. A key player in breast cancer is the histone demethylase lysine-specific demethylase 1 (LSD1). We used LSD1 knockdown MCF7 and T47D cell exosomes to treat breast cancer cells for greatly increasing the invasion and migration of breast cancer cells for evaluating the impact of LSD1 on breast cancer invasion and migration. miR-1290 expression was downregulated in LSD1 knockdown MCF7 exosomes. Furthermore, miR-1290 could control NAT1 expression by looking through the database of miR-1290 target genes. These data provide fresh insights into the biology of breast cancer therapy by demonstrating how the epigenetic factor LSD1 stimulates the breast cancer cells’ invasion and migration via controlling exosomal miRNA.
Project description:Background: Cancer metastasis is dependent on cell migration. Several mechanisms, including epithelial-to-mesenchymal transition (EMT) and actin fiber formation, could be involved in cancer cell migration. As a downstream effector of the Hippo signaling pathway, transcriptional coactivator with PDZbinding motif (TAZ) is recognized as a key mediator of the metastatic ability of breast cancer cells. We aimed to examine whether TAZ affects the migration of breast cancer cells through the regulation of EMT or actin cytoskeleton. Methods: MCF-7 and MDA-MB-231 cells were treated with siRNA to attenuate TAZ abundance. Transwell migration assay and scratch wound healing assay were performed to study the effects of TAZ knockdown on cancer cell migration. Fluorescence microscopy was conducted to examine the vinculin and phalloidin. Semiquantitative immunoblotting and quantitative real-time PCR were performed to study the expression of small GTPases and kinases. Changes in the expression of genes associated with cell migration were examined through next-generation sequencing. Results: TAZ-siRNA treatment reduced TAZ abundance in MCF-7 and MDA-MB- 231 breast cancer cells, which was associated with a significant decrease in cell migration. TAZ knockdown increased the expression of fibronectin, but it did not exhibit the typical pattern of EMT progression. TGF-b treatment in MDA-MB-231 cells resulted in a reduction in TAZ and an increase in fibronectin levels. However, it paradoxically promoted cell migration, suggesting that EMT is unlikely to be involved in the decreased migration of breast cancer cells in response to TAZ suppression. RhoA, a small Rho GTPase protein, was significantly reduced in response to TAZ knockdown. This caused a decrease in the expression of the Rho-dependent downstream pathway, i.e., LIM kinase 1 (LIMK1), phosphorylated LIMK1/2, and phosphorylated cofilin, leading to actin depolymerization. Furthermore, myosin light chain kinase (MLCK) and phosphorylated MLC2 were significantly decreased in MDA-MB-231 cells with TAZ knockdown, inhibiting the assembly of stress fibers and focal adhesions. Conclusion: TAZ knockdown inhibits the migration of breast cancer cells by regulating the intracellular actin cytoskeletal organization. This is achieved, in part, by reducing the abundance of RhoA and Rho-dependent downstream kinase proteins, which results in actin depolymerization and the disassembly of stress fibers and focal adhesions.
Project description:The contribution of aberrant DNA methylation and the downstream effects in tumorogenesis through silencing of tumor suppressor genes (TSGs) and microRNAs has been investigated. Since these epigenetic alterations can be reversed, we investigated the effects of the epigenetic therapy in breast cancer cell lines. We used microarrays to investigate the global microRNA expression profile after demethylation treatment with 5-aza-2’-deoxycytidine (DAC) in breast cancer cell lines and identified distinct classes of early and late systematic stable or transient effects of the treatment.
Project description:RASSF1C, unlike RASSF1A, is not a tumor suppressor, but instead may play a role in stimulating metastasis and survival in breast cancer cells RASSF1C over-expression enhances T47D cell invasion/migration in vitro Three RASSF1C over-expression samples vs three controls
Project description:We identified sensory nerves as more abundant in triple-negative human breast tumors. Human triple negative breast cancer (TNBC) cells (MDA-MB-231, SUM159) were co-cultured with mice primary sensory neurons from dorsal root ganglia (DRG). Breast can-cer cells were found to attach to neurons and have higher migration speed and prolifera-tion rate. Species-specific RNA sequencing highlighted cell migration and adhesion among the most upregulated pathways for cancer cells in coculture. We identified a novel mechanism where cancer’s PlexinB3 interacted with neuron’s Sema5A to regulate attachment and migration along nerve fibers. These findings demonstrate that sensory nerves induced a drastic shift in TNBC cells gene expression, and that dirupting the nerve-cancer is a viable strategy to impede metastasis
Project description:NFIC1, the longest isoform of NFIC, is essential for the regulation on spatiotemporal expressions of drug-metabolizing genes in liver. However, the role of NFIC1 in breast cancer is not clear. Here we showed that increased expression of NFIC1 suppressed the migration and invasion of MCF-7 cells. The activation of interferon-associated Jak-STAT pathway was enhanced with NFIC1 overexpression. NFIC1 overexpression upregulated the expression of IFNB1, IFNL1, IFNL2 and IFNL3. Treatment with Jak-STAT pathway inhibitors, Filgotinib or Ruxolitinib, reversed the suppressive effects of NFIC1 overexpression on migration and invasion. In addition, we found that MX1 and MX2 were the target genes of NFIC1- activated Jak-STAT pathway, which mediated the migration and invasion of MCF-7 cells. These results demonstrated that NFIC1 inhibited the migration and invasion in MCF-7 cells through interferon mediated activation of Jak-STAT pathway, indicating that Jak-STAT pathway might be a potential therapeutic target for preventing breast cancer metastasis.
Project description:This study investigates the role of Biglycan (BGN) in promoting epithelial migration during mammary gland development and breast cancer metastasis. Using in vitro and in vivo models, including a 3D organoid migration assay and single-cell RNA sequencing, we demonstrate that BGN enhances the interaction between WNT3A and FZD6, activating the WNT signaling pathway. This activation promotes epithelial cell migration and breast cancer metastasis. The findings provide new insights into breast cancer metastasis mechanisms and identify BGN as a potential therapeutic target.