Methylation of the IL6 promoter by EHMT1:EHMT2 (GLP:G9a) histone methyltransferases inhibits IL6 transcription, while Cdh1:APC/C-mediated degradation of EHTM1:EHTM2 downstream of the ATM-TP53-CDKN1A axis stimulates IL6 transcription (Takahashi et al. 2012). Oncogenic RAS signaling stimulates activation of the CEBPB transcription factor (C/EBP-beta) which binds IL6 promoter and stimulates IL6 transcription (Kuilman et al. 2008, Lee et al. 2010). NF kappa B transcription factor is also activated in senescent cells (Chien et al. 2011) through interleukin-1-alpha (IL1A) signaling (Jimi et al. 1996, Hartupee et al. 2008, Orjalo et al. 2009), and it cooperates with CEBPB in the activation of IL6 transcription (Shimizu et al. 1990, Libermann and Baltimore 1990, Matsusaka et al. 1993, Acosta et al. 2008). Autocrine IL6 signaling stimulates CEBPB expression (Kuilman et al. 2008), creating a positive feedback loop. STAT3, activated by IL6 signaling cascade is necessary for CEBPB transcription, but the direct binding of STAT3 to the CEBPB promoter has not been demonstrated (Niehof et al. 2001).