Next, to study why ASC-J9®-increased ATF3 can suppress PCa cell proliferation and invasion, we analyzed the potential ATF3 downstream targets via RNAseq assay, and results revealed the negative correlation showing the expression of PTK2, a key factor to promote the proliferation and invasion of cancer [50], is decreased with the increase of ATF3 (Fig. 4a), which is also in agreement with the result from correlation analysis of the database from Jacobson, J.R., et al. [51], showing the expression of ATF3 was negatively correlated with the expression of PTK2 (Fig. 4b). Here, PTK2 is linked to cancer.