CD7 and colorectal carcinoma: The results revealed a novel group of congenital lymphocytes, which expressed the T cell surface antigen Leu-9 (CD7+), neural cell adhesion molecule 1 (CD56+), and protein tyrosine phosphatase receptor type C (CD45RO+) at high levels, while did not express IL-7 receptor (CD127−) (Lin-CD7+CD127−CD56+CD45RO+), which was enriched in CRC tissues and showed cytotoxicity.