Instead of focusing on the growth of PDACs, the present study showed that retroperitoneal invasion and metastasis to the liver and lung from the PDAC tumors in cancer-bearing nude mice were suppressed by administration of target siRNA-FA-PEG-COL nanoparticles against ARHGEF4, CCDC88A, LAMTOR2, mTOR, NUP85, and WASF2. The key molecules that induce PDAC tumor progression bypass one signal transduction pathway via another pathway. The gene discussed is NUP85; the disease is neoplasm.