Our novel findings indicated that the current study used unsaturated fatty EPA to indirectly induce the expression of miR-378 in PCa cells, significantly resulting in the inhibition of KLK gene family (KLK2, KLK4, KLK6, and KLK14) activities in all the tested PCa cells, and further progressing the tumor cells towards apoptosis, without harming the normal tissues (p value < 0.05; Figure 7). The gene discussed is KLK4; the disease is neoplasm.