QPRT and breast cancer: On the other hand, chronic exposure to high levels of estradiol has been identified as a major cause of ER-positive breast cancer41, and it can upregulate Twist via the PI3K/AKT/NF-κB signalling pathway, thereby promoting the progression of hormone-dependent breast cancer42.These findings further support the notion that QPRT can influence the progression of breast cancer through the PI3K-AKT signalling pathway.