Of note, even though the single dose of 5E6 CAR-NK treatment did not result in full tumor control or clearance, analysis of cells in the bone marrow and spleen revealed the cells were still present and nearly 100% CAR-cassette expressing but showed high levels of T cell immunoreceptor with Ig and ITIM domains (TIGIT) expression (Figure S8), suggesting the CAR-NKs were able to home to the bone marrow niche and persist with exogenous IL-15 supplementation but may have hit exhaustion. This evidence concerns the gene TIGIT and neoplasm.