CD44 is a glycoprotein that is overexpressedon various types of cancerous cells, including breast cancer.23,24 CD44 is known to play a key role in metastasis and relapse of breastcancer.25,26 Hyaluronan (HA) is the major endogenousligand of CD44.23,27−29 Herein, wereport an ICG and HA conjugated iron oxide nanoparticle (NP-ICG-HA),which can bind well with CD44. This evidence concerns the gene CD44 and breast cancer.