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:Probe electrospray ionization mass spectrometry (PESI-MS) is an ambient ionization-based mass spectrometry method that surpasses the original electrospray ionization technique in features such as the rapidity of analysis, simplicity of the equipment and procedure, and lower cost. This study found that the PESI-MS system with machine learning has the potential to establish a lipid-based diagnosis of breast cancer with higher accuracy, using a simpler approach. Rapid mass spectrometry for breast cancer.
Project description:Lipid composition in cell membrane is closely associated with cell characteristics. Here, matrix-assisted laser desorption/ionization- Fourier transform ion cyclotron resonance mass spectrometry was employed to in situ determine membrane components of human mammary epithelial cells (MCF-10 A) and six different breast cancer cell lines (i.e., BT-20, MCF-7, SK-BR-3, MDA-MB-231, MDA-MB-157, and MDA-MB-361) without any lipid extraction and separation. Partial least-square discriminant analysis indicated that changes in the levels of these membrane lipids were closely correlated with the types of breast cell lines. Elevated levels of polyunsaturated lipids in MCF-10 A cells relative to six breast cancer cells and in BT-20 cells relative to other breast cancer cell lines were detected. The Western blotting assays indicated that the expression of five lipogenesis-related enzymes (i.e., fatty acid synthase 1(FASN1), stearoyl-CoA desaturase 1 (SCD1), stearoyl-CoA desaturase 5 (SCD5), choline kinase α (CKα), and sphingomyelin synthase 1) was associated with the types of the breast cells, and that the SCD1 level in MCF-7 cells was significantly increased relative to other breast cell lines. Our findings suggest that elevated expression levels of FASN1, SCD1, SCD5, and CKα may closely correlated with enhanced levels of saturated and monounsaturated lipids in breast cancer cell lines.
Project description:Plasma and tissue from breast cancer patients are valuable for diagnostic/prognostic purposes and are accessible by multiple mass spectrometry (MS) tools. Liquid chromatography-mass spectrometry (LC-MS) and ambient mass spectrometry imaging (MSI) were shown to be robust and reproducible technologies for breast cancer diagnosis. Here, we investigated whether there is a correspondence between lipid cancer features observed by desorption electrospray ionization (DESI)-MSI in tissue and those detected by LC-MS in plasma samples. The study included 28 tissues and 20 plasma samples from 24 women with ductal breast carcinomas of both special and no special type (NST) along with 22 plasma samples from healthy women. The comparison of plasma and tissue lipid signatures revealed that each one of the studied matrices (i.e., blood or tumor) has its own specific molecular signature and the full interposition of their discriminant ions is not possible. This comparison also revealed that the molecular indicators of tissue injury, characteristic of the breast cancer tissue profile obtained by DESI-MSI, do not persist as cancer discriminators in peripheral blood even though some of them could be found in plasma samples.
Project description:The extracted MRM peaks from LC-MS/MS experiments were integrated using Agilent MassHunter Quantitative Data Analysis software. Data extraction for GC-MS experiments was performed using Agilent MassHunter Profinder software.
Project description:Methanococcus maripaludis is a methanogenic archaeon. Within its genome, there are two operons for membrane associated hydrogenases, eha and ehb. To investigate the regulation of ehb on the cell, an S40 mutant was constructed in such a way that a portion of the ehb operon was replaced by pac cassette in the wild type parental strain S2 (done by Whitman's group at the University of Georgia). The S40 and S2 strains were grown in 14N and 15N media with acetate separately. A biological replicate was made by switching the media. Mass spectrometry based quantitative proteomics were done on the mixtures to investigate the differences in expression patterns between S40 and S2. Keywords: isotope labeling mass spectrometry, quantitative proteomics
Project description:Colorectal cancer (CRC) ranks third in incidence and second in mortality among cancers worldwide. Emerging researches showed that microRNAs (miRNAs) play an important role in CRC progression. Here, we aimed to investigate the expression and regulatory mechanism of miR-1290 in CRC. miR-1290 is significantly overexpressed in CRC primary tissues and metastatic tissues compared to that in normal tissues, and up-regulated miR-1290 is correlated with poor overall survival (OS) of CRC patients. Functional experiments showed that miR-1290 can promote the proliferation, migration, invasion and inhibit apoptosis of CRC cells. Mechanistically, miR-1290 directly targets KLF9 and promotes the malignancy progression of CRC cells through regulating MMP9 and p53 expression, subsequently. In addition, high H3K4me3 levels in miR-1290 promoter region activate its transcription in CRC. In summary, our study demonstrated the expression and regulatory mechanism of miR-1290 in CRC which supports the notion that therapeutic targeting of miR-1290 may be a promising treatment approach for CRC patients.
Project description:MicroRNAs (miRNAs) are known to be deregulated in human breast cancer (BC). The purpose of the current study was to investigate the expression of miRNAs in different stages of BC to assess their biological value in BC progression. MiRNA expression was assessed in a series of BC patients (n=7) with distinct stages of tumour progression (Normal, in-situ (DCIS), primary invasive BC and nodal metastases) to evaluate miRNA differential expression. We used an Agilent miRNA microarray based platform which uses miRBase 16 to screen for 1205 Homo sapiens (hsa) and 144 human viral miRNA candidates. To validate the microarray data, the expression of two deregulated miRNAs was measured by TaqMan quantitative real-time reverse transcription polymerase chain reaction (qRT-PCR).