Recent studies have found that the short-chain fatty acids (SCFAs) valerate and butyrate inhibit histone deacetylase (HDACs), increase production of effector factors (CD25, IFN-γ and TNF-α) and enhance the antitumor activity of receptor tyrosine kinase-like orphan receptor 1 (ROR1) targeting CAR T cells and CTLs in mouse melanoma and pancreatic cancer adoptive metastasis models [55], which has a positive effect on the clinical application of adoptive T-cell therapy. Here, ROR1 is linked to pancreatic neoplasm.