KRAS and neoplasm: Moreover, to observe the effect of whole-body Atg4BCA expression on tumor growth, the orthotopic implantation of Kras-driven pancreatic cancer cells expressing or lacking Atg4B dominant negative (DN) in hosts, with or without systemic Atg4BCA expression, revealed that stromal cell ATG4B enhanced early tumor establishment, but its role diminished over time, with Atg4B DN in tumor cells becoming more significant in slowing tumor growth.