Furthermore, we are first to report that expression levels of Rab27B appeared to increase with the magnitude of cancer progression: a significant increasing expression of Rab27B was observed from normal breast tissue, to FA, DCIS, and to invasive BC, metastatic LNs In our study, further correlation analysis revealed for the first time that high Rab27B expression was closely correlated with an aggressive phenotype of BC, including ascending pathologic grade, advanced clinical stage, and lymph node metastasis. Here, RAB27B is linked to breast cancer.