JAG2 and breast cancer: Importantly, the result revealed that not only Mel treatment significantly suppressed, but also silenced Notch/JAG2 gene further significantly suppressed the protein expressions and the PI3K/AKT/mTOR signaling in UMUC3 cells inevitably leading us to raise the hypothesis that upstream signaling of Notch/JAG2 might play a principal role on the growth, proliferation and invasion/metastasis of BC essentially through upregulating the PI3K/AKT/mTOR downstream signaling.