In line with earlier research, it has been found that CPO inhibits tumour growth and induces apoptosis in human prostate and breast cancer cells by inhibiting PI3K/AKT/mTOR/S6K1 [31] and in non-small cell lung cancer by affecting miR-659-3p-targeted sphingosine kinase 1 [35]. This evidence concerns the gene SPHK1 and breast carcinoma.