Pathways significantly (p ≤ 0.05) enriched in the cancer cells invading the nerves (Table S4) also included ERK5 signaling, signaling by NTRK1, Gap Junction signaling, the HOTAIR Regulatory Pathway and the WNT/SHH Axonal Guidance Signaling Pathway, all previously reported to be involved in PDAC carcinogenesis and/or PNI [10,26,27,28]. Here, SHH is linked to cancer.