Fourth, pharmacological USP22 inhibition impairs BCSC self-renewal and protects mice from breast cancer lung metastasis-induced mortality; Last but not least, USP22 and ITGB1 are positively correlated in more than 90% of human cancer types, and USP22, integrin b1 and FoxM1 are increased and positively correlated in breast cancers. Here, FOXM1 is linked to breast cancer.