Increased hsp70 levels directly correlate with STAT5 levels and transcriptional activity. (A) Immunoblot analyses of total cell lysate from HL-60/Neo, HL-60/hsp70, HL-60/Bcr-abl, K562, and K562AS HSP70 cells, using anti-STAT5 or p-STAT5 antibodies. β-actin levels were used as loading control. (B) In the indicated cell types, the mRNA level of STAT5 was determined by reverse-transcription PCR, with β-actin mRNA as the control. (C) Nuclear extracts from the indicated cell types also were subjected to EMSA to estimate levels of STAT 5 DNA binding activity. Supershift of the STAT5 band was demonstrated by using anti-STAT5 antibody. (D) Immunoblot analyses of c-Myc, oncostatin-M, Bcl-xL, and β-actin in the cell lysates obtained from the indicated cell lines.
