STAT3 and plasma cell myeloma: Moreover, inhibition of NF-κB pathway by bortezomib is considered to be as one of major factors for its anti-myeloma activity (Yang et al., 2008; Demchenko and Kuehl, 2010), although several other oncogenic signal transduction cascades such as STAT3/Akt and ERK kinase have also been reported to be modulated upon bortezomib treatment (Mitsiades et al., 2002; Hideshima et al., 2003).