MYC and breast cancer: Gupta et al., using breast cancer cell lines (MCF-7, 4T1) in vitro and in vivo, found that penfluridol inhibits cell proliferation and migration by suppressing the HER2/β-catenin signaling pathway as well as its associated molecules (TCF-4, TCF-1, Cyclin D1, C-MYC, p-GSK3β) and inducing apoptosis (increased cleavage of caspase-3 and C1-PARP).