In this report, public data mining, galectin-binding and glycosyltransferase expression assessments and glycomics showed that galectin (Gal)-3 was elevated in lymphoma-associated microenvironments and that anti-CD19 CAR-T cells displayed abundant Gal-3-binding glycans, reduced expression of the Gal-3-inhibitory enzyme α2,6-sialyltransferase 1 (<i>ST6GAL1</i>), and heightened susceptibility to Gal-3-mediated immunoregulation. The gene discussed is LGALS3; the disease is lymphoma.