PTGS2 and cancer: Due to the involvement of inflammation in the early stages of cancer development and our previous findings in the C10 cells demonstrating increased Cox-2 (Ptgs2) mRNA expression in response to the LMW binary PAH mixture (Osgood et al. 2017), we evaluated Cox-2 expression at 24 h in the same PAH combinations described above but at 8 and 40 times lower levels as we used previously, 5 and 1 μM PAH mix (Fig. 8).