Project description:How cancer cells adapt to hypoxia during tumor development remains an important question. The hypothesis tested in the present study was that tumor cell-derived exosome vesicles (also known as microvesicles or extracellular vesicles) are mediators of hypoxia-dependent intercellular signaling in glioblastoma (GBM), i.e. highly aggressive brain tumors characterized by hypoxia and a vascular density that is among the highest of all human malignancies. In vitro hypoxia experiments and studies with patient materials reveal the enrichment in exosomes of hypoxia-regulated mRNAs and proteins, several of which were associated with poor patient prognosis. We show that cancer cell exosomes mediate hypoxia-dependent, phenotypic modulation of stromal cells in vitro and ex vivo, resulting in accelerated GBM tumor angiogenesis and growth in mice. These data suggest that exosomes constitute potent mediators of hypoxia-driven tumor development, and circulating multiparameter biomarkers of tumor hypoxia. U87 MG glioblastoma cells were grown at normoxic (21% oxygen) or hypoxic (1% oxygen) conditions for 48 hours. Conditioned media from normoxic and hypoxic cells were then used to isolate exosomes by differential centrifugation. Both cells and exosomes were lysed in Trizol reagent, and RNA was isolated.Total RNA from all samples (four types of samples in three biological repilicates) was subjected to genome-wide transcriptional analysis with Illumina HumanHT-12 V3.0 expression beadchip. Gene expression profile obtained from hypoxic U87 MG glioblastoma cells was compared to the profile of normoxic control cells. Analogically, gene expression profile obtained from hypoxic U87 MG cells was compared to the profile of exosomes secreted by normoxic U87 MG cells.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression.
Project description:Genome wide DNA methylation profiling of control and mTORC2-suppressed glioblastoma cells (U87-EGFRvIII cells). The Illumina Infinium HumanMethylation EPIC BeadChip Array was used to obtain DNA methylation profiles with 865,918 probes in glioblastoma cell line samples. Samples included 2 control U87-MG cells without mTORC2 suppresion, and mTORC2-knockdown U87-MG cells with lentivirus-mediated suppression of mTORC2.
Project description:Transcriptional profiling of human mesenchymal stem cells comparing normoxic MSCs cells with hypoxic MSCs cells. Hypoxia may inhibit senescence of MSCs during expansion. Goal was to determine the effects of hypoxia on global MSCs gene expression. Two-condition experiment, Normoxic MSCs vs. Hypoxic MSCs.
Project description:Glioblastoma cells are characterized by a highly invasive behavior whose mechanisms are not yet understood. Using the wound healing and Boyden chamber assays we compared in the present study the migration and invasion abilities of 5 glioblastoma cell lines (DK-MG, GaMG, U87-MG, U373-MG, SNB19) differing in p53 and PTEN status. We also analyzed by Western blotting the expression of PTEN, p53, mTOR and several other marker proteins involved in cell adhesion, migration and invasion. Among 5 cell lines, GaMG cells exhibited the fastest rate of wound closure, whereas U87-MG cells showed the most rapid chemotactic migration in the Boyden chamber assay. In DK-MG and GaMG cells, F-actin mainly occurred in the numerous stress fibers spanning the cytoplasm, whereas U87-MG, U373-MG and SNB19 cells preferentially expressed F-actin in filopodia and lamellipodia. Moreover, the two glioblastoma lines mutated in both p53 and PTEN genes (U373-MG and SNB19) were found to exhibit the fastest invasion rates through the Matrigel matrix.
Project description:Purpose: Hypoxia is a predominant feature in GBM and its microenvironment. It is associated with the tumor growth, progression and resistance to conventional therapy of GBM. We have utilized U87-MG cell line as a human GBM cell model and human brain HEB cell line as non-neoplastic brain cell cultured in different levels of hypoxia for transcriptional profiling to identify the transcriptional signature of U87-MG cells for elucidated the role of hypoxia in GBM phenotype. Methods: We have utilized U87-MG cell line as a human GBM cell model and human brain HEB cell line as non-neoplastic brain cell cultured in 21%, 5% and 1% O2 for 24h. Then we detected the changes of transcriptional profiling and analyzed the biological process and pathway for the genes with different expression modes in different hypoxia levels. Results: U87-MG cells present specific transcriptional signature response to different hypoxia levels. The genes associated with organ and system development present an upward trend from normoxia to extreme hypoxia. And the biological process of DNA repair presents a downward trend, indicating that gene mutations of U87-MG cells could derive by hypoxia microenvironment. Otherwise, HEB cells present the canonical response to hypoxia, reducing of the metabolic rate in concert with the degree of hypoxia and extracting more oxygen from the environment. Conclusion: Hypoxia microenvironment could promote the malignance of GBM through activate of genes involved in organ and system development. Meanwhile it could induce the mutations of genes in GBM, especially extreme hypoxia.
Project description:Glioblastoma cells are characterized by a highly invasive behavior whose mechanisms are not yet understood. Using the wound healing and Boyden chamber assays we compared in the present study the migration and invasion abilities of 5 glioblastoma cell lines (DK-MG, GaMG, U87-MG, U373-MG, SNB19) differing in p53 and PTEN status. We also analyzed by Western blotting the expression of PTEN, p53, mTOR and several other marker proteins involved in cell adhesion, migration and invasion. Among 5 cell lines, GaMG cells exhibited the fastest rate of wound closure, whereas U87-MG cells showed the most rapid chemotactic migration in the Boyden chamber assay. In DK-MG and GaMG cells, F-actin mainly occurred in the numerous stress fibers spanning the cytoplasm, whereas U87-MG, U373-MG and SNB19 cells preferentially expressed F-actin in filopodia and lamellipodia. Moreover, the two glioblastoma lines mutated in both p53 and PTEN genes (U373-MG and SNB19) were found to exhibit the fastest invasion rates through the Matrigel matrix. Here, we performed a gene expression profiling of the five glioblastoma cell lines to examine the molecular framework of differences in invasive behavior to find possible targets for chemo- and radiation therapy.
Project description:Purpose:Glioblastoma (GBM) is the most common primary brain tumor in adults with poor prognosis and short medial survival after therapy. we have utilized U87-MG cell line as a human GBM cell model and human brain HEB cell line as non-neoplastic brain cell cultured in normoxia and 1% O2 hypoxia for transcriptional profiling to gain further insight into the molecular underpinnings that maintained the properties of GBM andclarify the molecular mechanism of hypoxia resistance of GBM. Methods:We have utilized U87-MG cell line as a human GBM cell model and human brain HEB cell line as non-neoplastic brain cell cultured in normoxia and 1% O2 hypoxia for transcriptional profiling. And validating the analysis results with specimens of GBM patients. Results: Firstly, the resulting data set revealed previously unknown proteins, including AKR1B1, MT2A, UBC, EEF1A1 and MTRNR2l2 in U87-MG cells, which promoted GBM characters through MAPK pathway. Meanwhile, we found that toll-like pathway was a new avenue mediating the function of inflammatory response in GBM. Furthermore, The results suggested that cytokine TGF-β1 and HIFs’ targeted genes, including HMOX1 and STC1 could be regard as hypoxic markers for GBM. Conclusion:Taken together, our study identified new potential biomarkers and illustrated the genes associated with inflammation in GBM. More importantly, the unique pattern to hypoxia implied new insight for the GBM research of hypoxia resistance and recurrence in future.
Project description:Total RNA were extracted from Guanylate Cyclase Soluble Subunit Beta-3 (GUCY1B3) overexpression U87 MG stable cell lines and U87 MG cells. Three RNA samples of each of the two cell lines were used for microarray analysis to compare gene expression profile