A preparation of autologous T-lymphocytes that are genetically engineered, using a lentiviral vector, to express a chimeric antigen receptor (CAR) targeting the enterocyte differentiation antigen guanylyl cyclase C (GUCY2C), with potential immunostimulating and antineoplastic activities. Upon intravenous administration, the autologous GCC-targeting CAR T-cells LCAR-G08 are directed to, specifically bind to, activate, proliferate and release cytokines that promote killing of GCC-expressing tumor cells. GCC is overexpressed in various tumor cell types.