Fluorescence microscopy has previously revealed the internalization of Hsp70 and granzyme B (GrB) into the CT26 murine colon cancer cell line involves Rab and LAMP dependent vesicles [30], and we therefore anticipated that the internalization of TPP also involves an endosomal pathway which is associated with Rab proteins inside tumor cells. This evidence concerns the gene GZMB and malignant colon neoplasm.