Project description:Transcriptomic profiling of SOX4 knock-down MDA-LM2 cell line resulted in down-regulation of its transcriptional target gene, TMEM2. Two independent siRNAs were used to knock down SOX4 in metastatic MDA-LM2 cells. The cells were then subjected to transcripome profiling in comparison to control siRNA-transfected cells.
Project description:Preclinical breast cancer models recapitulating the clinical course of metastatic disease are crucial for drug development. Highly metastatic cell lines forming spontaneous metastasis following orthotopic implantation were previously developed and characterized regarding their biological and histological characteristics. This study aimed to non-invasively and longitudinally characterize the spatiotemporal pattern of metastasis formation and progression in the MDA-MB-231-derived triple negative LM2-4 and HER2+ LM2-4H2N cell lines, using bioluminescence imaging (BLI), contrast enhanced computed tomography (CT), fluorescence imaging, and 2-deoxy-2-[fluorine-18]fluoro-D-glucose positron emission tomography ([18F]FDG-PET).LM2-4, LM2-4H2N, and MDA-MB-231 tumors were established in the right inguinal mammary fat pad (MFP) of female SCID mice and resected 14-16 days later. Metastasis formation was monitored using BLI. Metabolic activity of primary and metastatic lesions in mice bearing LM2-4 or LM2-4H2N was assessed by [18F]FDG-PET. Metastatic burden at study endpoint was assessed by CT and fluorescence imaging following intravenous dual-modality liposome agent administration.Comparable temporal metastasis patterns were observed using BLI for the highly metastatic cell lines LM2-4 and LM2-4H2N, while metastasis formed about 10 days later for MDA-MB-231. 21 days post primary tumor resection, metastases were detected in 86% of LM2-4, 69% of LM2-4H2N, and 60% of MDA-MB-231 inoculated mice, predominantly in the axillary region, contralateral MFP, and liver/lung. LM2-4 and LM2-4H2N tumors displayed high metabolism based on [18F]FDG-PET uptake. Lung metastases were detected as the [18F]FDG-PET uptake increased significantly between pre- and post-metastasis scan. Using a liposomal dual-modality agent, CT and fluorescence confirmed BLI detected lesions and identified additional metastatic nodules in the intraperitoneal cavity and lung.The combination of complementary anatomical and functional imaging techniques can provide high sensitivity characterization of metastatic disease spread, progression and overall disease burden. The described models and imaging toolset can be implemented as an effective means for quantitative treatment response evaluation in metastatic breast cancer.
Project description:BackgroundLipid nanocapsules (LNCs) are promising vehicles for drug delivery. However, since not much was known about cellular toxicity of these nanoparticles in themselves, we have here investigated the mechanisms involved in LNC-induced intoxication of the three breast cancer cell lines MCF-7, MDA-MD-231 and MDA-MB-468. The LNCs used were made of Labrafac™ Lipophile WL1349, Lipoid® S75 and Solutol® HS15.ResultsHigh resolution SIM microscopy showed that the DiD-labeled LNCs ended up in lysosomes close to the membrane. Empty LNCs, i.e. without encapsulated drug, induced not only increased lysosomal pH, but also acidification of the cytosol and a rapid inhibition of protein synthesis. The cytotoxicity of the LNCs were measured for up to 72 h of incubation using the MTT assay and ATP measurements in all three cell lines, and revealed that MDA-MB-468 was the most sensitive cell line and MCF-7 the least sensitive cell line to these LNCs. The LNCs induced generation of reactive free oxygen species and lipid peroxidation. Experiments with knock-down of kinases in the near-haploid cell line HAP1 indicated that the kinase HRI is essential for the observed phosphorylation of eIF2?. Nrf2 and ATF4 seem to play a protective role against the LNCs in MDA-MB-231 cells, as knock-down of these factors sensitizes the cells to the LNCs. This is in contrast to MCF-7 cells where the knock-down of these factors had a minor effect on the toxicity of the LNCs. Inhibitors of ferroptosis provided a large protection against LNC toxicity in MDA-MB-231 cells, but not in MCF-7 cells.ConclusionsHigh doses of LNCs showed a different degree of toxicity on the three cell lines studied, i.e. MCF-7, MDA-MD-231 and MDA-MB-468 and affected signaling factors and the cell fate differently in these cell lines.
Project description:BACKGROUND:The development of oral squamous cell carcinoma (OSCC) is a multistep process that involves in both genetic alterations and epigenetic modifications. Previous studies suggest SOX4 might function as an oncogene or a tumor suppressor in different types of cancers. However, whether SOX4 involves in promoting the progression of oral precancer to cancer is unknown. METHODS:Liquid chromatography with tandem mass spectrometry (LC-MS/MS) was used to identify the proteins that may be differentially expressed between oral lichen planus (OLP) and OLP-associated OSCC (OLP-OSCC) formalin-fixed paraffin-embedded (FFPE) tissues. Immunohistochemistry (IHC) and Western blotting were performed to evaluate SOX4 expression between OLP and OLP-OSCC tissues and among oral cancer cell lines and normal human oral keratinocytes (NHOKs). SOX4 siRNA was used to knock down the expression of SOX4 in UM1 oral cancer cells. MTT, cell counting, migration and Matrigel invasion assays were utilized to examine the effect of SOX4 down-regulation on proliferation, migration and invasion capacity of UM1 cells. RESULTS:LC-MS/MS analysis showed that 88 proteins including SOX4 were only identified in OLP-OSCC FFPE tissues when compared to OLP FFPE tissues. IHC confirmed that SOX4 expression was significantly higher in OLP-OSCC than OLP and Western blot analysis indicated that SOX4 was over-expressed in UM1/UM2 cells when compared to NHOKs. Knockdown of SOX4 significantly inhibited the proliferation, migration and invasion of UM1 cells (P<0.01). CONCLUSIONS:Our study indicated that SOX4 is significantly upregulated in OLP-OSCC versus OLP tissues. In addition, down-regulation of SOX4 led to significantly reduced proliferation, migration and invasion capability of oral cancer cells. These findings suggest that SOX4 might be actively involved in the progression of OLP to OSCC.