Journal:

Article Title: Linkage between STAT Regulation and Epstein-Barr Virus Gene Expression in Tumors

doi: 10.1128/JVI.75.6.2929-2937.2001

Figure Lengend Snippet: The L1-TR LMP1 promoter is responsive to the STAT activators JAK1 and IL-6 and has reduced activity in JAK mutant cell lines. (a) Reporter assay showing induction of CAT expression from L1-TRp–CAT in HeLa cells cotransfected with a JAK1 expression vector or treated for 48 h with human IL-6 (100 ng/ml). The results shown are an average of three experiments, with the standard deviation indicated. (b) Reporter assay comparing CAT expression from L1-TRp–CAT and L1-TR(mt)p–CAT in parental (2fTGH) versus TYK2 (U1A) and JAK1 (U4A) mutant cells. The STAT binding site is mutated in L1-TR(mt)p–CAT. The promoter in TK-CAT is the non-STAT-regulated herpes simplex thymidine kinase promoter. The results shown are an average of three experiments, with the standard deviation indicated.

Article Snippet: Induction with interleukin-6 was achieved by incubating B95-8 cells in medium plus 100 ng of human interleukin-6 (IL-6) (R&D Systems, Minneapolis, Minn.) per ml for 48 h before harvesting the cells for RNA extraction.

Techniques: Activity Assay, Mutagenesis, Reporter Assay, Expressing, Plasmid Preparation, Standard Deviation, Binding Assay

Journal:

Article Title: Linkage between STAT Regulation and Epstein-Barr Virus Gene Expression in Tumors

doi: 10.1128/JVI.75.6.2929-2937.2001

Figure Lengend Snippet: The endogenous L1-TR promoter in B95-8 cells is activated by IL-6. Southern blot analyses of RT-PCR products generated from B95-8 lymphoblastoid cells using the P1 and P2 primers for L1-TRp initiated mRNA (top) or primers for the polymerase III EBER1 RNAs (bottom) are shown. cDNAs were detected using specific 32P-labeled oligonucleotide probes. Growth of B95-8 cells in medium containing IL-6 increased the amount of the 749-bp L1-TR-initiated LMP1 mRNA but did not affect EBER1 RNA levels. The larger PCR product was also generated in the absence of the RT reaction.

Article Snippet: Induction with interleukin-6 was achieved by incubating B95-8 cells in medium plus 100 ng of human interleukin-6 (IL-6) (R&D Systems, Minneapolis, Minn.) per ml for 48 h before harvesting the cells for RNA extraction.

Techniques: Southern Blot, Reverse Transcription Polymerase Chain Reaction, Generated, Labeling

Journal:

Article Title: Linkage between STAT Regulation and Epstein-Barr Virus Gene Expression in Tumors

doi: 10.1128/JVI.75.6.2929-2937.2001

Figure Lengend Snippet: Model for in vivo EBV gene regulation and tumorigenesis. In primary infection, EBNA2 regulates the expression of the nuclear EBNAs and the LMP genes including LMP1 and modulates cellular gene expression. The strong immune response to the immunogeneic EBNAs limits the occurrence of EBNA2-expressing tumors to immunocompromised individuals. During in vivo latency, in the absence of EBNA2, the EBNA1 and LMP1 genes are regulated by STATs. Chronic activation of STATs through a natural cytokine signaling event such as inflammation or through aberrant oncogene-activated signaling may upregulate EBV EBNA1 and LMP1 expression and predispose the cell to EBV-driven tumorigenesis.

Article Snippet: Induction with interleukin-6 was achieved by incubating B95-8 cells in medium plus 100 ng of human interleukin-6 (IL-6) (R&D Systems, Minneapolis, Minn.) per ml for 48 h before harvesting the cells for RNA extraction.

Techniques: In Vivo, Infection, Expressing, Activation Assay

Journal:

Article Title: Linkage between STAT Regulation and Epstein-Barr Virus Gene Expression in Tumors

doi: 10.1128/JVI.75.6.2929-2937.2001

Figure Lengend Snippet: Potentiation of STAT signaling by LMP1. LMP1 may contribute to a self-sustaining cycle of STAT activation and continued LMP1 synthesis. LMP1 upregulates expression of the cytokine IL-6 and EGFR, which mediate tyrosine phosphorylation of STAT1 and STAT3. LMP1 is also able to activate JAK3, whose targets include STAT5. In addition, LMP1 increases the activity of JNK, a kinase involved in serine phosphorylation of the STAT protein transcriptional activation domain. Thus, STAT-induced LMP1 expression may lead to a state of constitutive STAT activation that can be maintained independently of ongoing external signaling.

Article Snippet: Induction with interleukin-6 was achieved by incubating B95-8 cells in medium plus 100 ng of human interleukin-6 (IL-6) (R&D Systems, Minneapolis, Minn.) per ml for 48 h before harvesting the cells for RNA extraction.

Techniques: Activation Assay, Expressing, Activity Assay