Egfp stat1

The pIRES-EGFP2 plasmid encoding FLAG-tagged DLX4 has been previously described [25 (link)]. The DLX4 cDNA was subcloned into the pRetroQ-AcGFP retroviral vector (Clontech). Other plasmids were as follows: pGFP-V-RS plasmids containing non-targeting and DLX4 shRNAs (OriGene Technologies), pGIPZ plasmids containing NOS2 shRNAs (GE Healthcare), eGFP-STAT1 (provided by Alan Perantoni, National Cancer Institute, Frederick, MD; Addgene plasmid 12301) [48 (link)], pRc/CMV-Flag STAT1α Y701F [28 (link)] (provided by James Darnell, Rockefeller University, New York, NY; Addgene plasmid 8702). A firefly luciferase reporter construct driven by tandem GAS elements was purchased from SABiosciences.

STAT1 siRNA and scramble RNA were purchased from Santa Cruz Biotechnology (Santa Cruz, CA, USA). Transfection of siRNA was performed using Lipofectamine RNAimax (Invitrogen, Carlsbad, CA, USA) according to the manufacturer’s instructions. Plasmids including eGFP-STAT1, eGFP-STAT1Y701F, eGFP-STAT1S727A, Flag-STAT1β were purchased from Addgene (Cambridge, MA, USA). Flag-tagged, constitutive-active STAT1 (or STAT1C) cloned into the backbone of pcDNA3.1 was a gift from Dr. Toru Ouchi (Roswell Park Cancer Institute, University at Buffalo, NY, USA). The constitutively active MEK-1 (HA-ca-MEK) vector was a gift from Dr. Nathalie Rivard (Université de Sherbrooke, Québec, CA). The proteasome inhibitor N-carbobenzoxyl-L-leucinyl-L-norleucinal (MG132) was purchased from Calbiochem (La Jolla, CA, USA) and 5-Aza-2′-deoxycytidine (5-Aza) was purchased from Sigma (St Louis, MO, USA). U0126, a Mitogen-activated protein kinase 1 (MEK1) inhibitor was purchased from Sigma (St Louis, MO, USA).