Cooperative signaling through the signal transducer and activator of transcription 3 and nuclear factor-κB pathways in subtypes of diffuse large B-cell lymphoma

ER stress transcription factor Xbp1 suppresses intestinal tumorigenesis and directs intestinal stem cells

“…Total Stat3 as well as Jak1 and Jak2 was also increased (Fig. 3 A), which might reflect the known capacity of Stat3 to bind its own promoter and to transactivate its transcription (Narimatsu et al, 2001;Lam et al, 2008;Snyder et al, 2008). Increased p-Stat3 was independent of Ire1 as Xbp1 /(IEC) ;Ern1 /(IEC) and Xbp1 /(IEC) ;Ern1 +/+(IEC) epithelia exhibited similar levels (Fig.…”

Essential role of MALT1 protease activity in activated B cell-like diffuse large B-cell lymphoma

“…Moreover, it correlated with a clear decrease in the cellular levels of both total and phosphorylated STAT3 (Fig. 3E), most likely as a consequence of reduced cytokine receptor-induced signals that control the JAK2-dependent phosphorylation of STAT3 and the subsequent P-STAT3-and NF-B-dependent feed-forward control of STAT3 gene expression in these cells (19).…”

“…Different ABC DLBCL tumors have been shown to express distinct but overlapping profiles of cytokines, most likely reflecting synergistic activity of NF-B with other transcription factors such as STAT3 that is constitutively activated in some ABC DLBCL (19). Expression of the growth-promoting cytokine IL-6, for example, is coordinatively regulated by STAT3 and NF-B at the transcriptional level, and is therefore secreted in high concentrations by OCI-Ly3 cells, which belong to the recently described STAT3-high subtype of ABC DLBCL (19). In these cells, the MALT1 inhibitor showed a strong reduction in the production of IL-6 (Fig.…”

Compensatory IKKα activation of classical NF-κB signaling during IKKβ inhibition identified by an RNA interference sensitization screen

“…IKK␤ shRNA (3) and NIK shRNA (9) sequences were described previously. IKK␣ knockdown was assessed by Western blotting (39).…”