To further understand the underlying molecular mechanisms of OS drug resistance, we used both G-292 and SJSA-1 cells to measure the activities of the following six cancer-related signaling pathways: p53/DNA damage, NF-кB, MAPK/ERK, ATF2/ATF3/ATF4, cAMP/PKA and MEF2 (Figure 6A). Here, ATF2 is linked to cancer.