Fig. 7

The role of TRAF6 in OSCC cells treated with combined bortezomib and IR treatment. a TRAF6-mediated polyubiquitination causes cell proliferation, tumor growth and anti-apoptosis during tumorigenesis of oral cancer. b IR treatment alone induces apoptosis. However, IR also induces phosphorylation of ATM and then increases TRAF6 polyubiquitination and phosphorylation of NF-kB, eventually leading to anti-apoptosis and IR resistance. c Bortezomib inhibits IR-induced TRAF6 polyubiquitination. Furthermore, bortezomib inhibits TRAF6-mediated Akt activation and induces autophagy-mediated programmed cell death (PCD)