ZEB1 and colorectal carcinoma: Nevertheless, CYB5R1 staining is not absolutely exclusive to infiltrative dissociating tumor cells but extends to the glandular tumor cell compartment, especially in cases with strong CYB5R1 expression, which mirrors limited exclusiveness of other core EMT markers for morphologically dissociating CRC cells, such as ZEB1 and SNAIL1 [21, 23].