Triple‐negative breast cancer (TNBC) is a highly lethal malignancy with limited therapy options. TWIST1, a key transcriptional factor of epithelial‐mesenchymal transition (EMT), contributes to self‐renewal of cancer stem‐like cells (CSCs), chemo‐resistance, metastasis, and TNBC‐related death. However, the mechanism by which TWIST1 is deregulated in TNBC remains elusive. Here, USP29 is identified as a bona fide deubiquitinase of TWIST1. The deubiquitination of TWIST1 catalyzed by USP29 is required for its stabilization and subsequent EMT and CSC functions in TNBC, thereby conferring chemotherapeutic resistance and metastasis. Furthermore, the results unexpectedly reveal that CDK1 functions as the direct USP29 activator. Mechanistically, CDK1‐mediated phosphorylation of USP29 is essential for its deubiquitinase activity toward TWIST1 and TWIST1 driven‐malignant phenotypes in TNBC, which could be markedly mitigated by the genetic ablation or pharmacological inhibition of CDK1. Moreover, the histological analyses show that CDK1 and USP29 are highly upregulated in TNBC samples, which positively correlate with the expression of TWIST1. Taken together, the findings reveal a previously unrecognized tumor‐promoting function and clinical significance of the CDK1‐USP29 axis through stabilizing TWIST1 and provide the preclinical evidence that targeting this axis is an appealing therapeutic strategy to conquer chemo‐resistance and metastasis in TNBC.

Rapid and ultrasensitive detection of pathogen-associated biomarkers is vital for the early diagnosis and therapy of bacterial infections. Herein, we developed a close-packed and ordered Au@AgPt array coupled with a cascade triggering strategy for surface-enhanced Raman scattering (SERS) and colorimetric identification of the Staphylococcus aureus biomarker micrococcal nuclease (MNase) in serum samples. The trimetallic Au@AgPt nanozymes can catalyze the oxidation of 3,3’,5,5’-tetramethylbenzidine (TMB) molecules to SERS-enhanced oxidized TMB (oxTMB), accompanied by the color change from colorless to blue. In the presence of S. aureus, the secreted MNase preferentially cut the nucleobase AT-rich regions of DNA sequences on magnetic beads (MBs) to release alkaline phosphatase (ALP), which subsequently mediated the oxTMB reduction for inducing the colorimetric/SERS signal fade away. Using this “on-to-off” triggering strategy, the target S. aureus can be recorded in a wide linear range with a limit of detection of 38 CFU/mL in the colorimetric mode and 6 CFU/mL in the SERS mode. Meanwhile, the MNase-mediated strategy characterized by high specificity and sensitivity successfully discriminated between patients with sepsis (n = 7) and healthy participants (n = 3), as well as monitored the prognostic progression of the disease (n = 2). Overall, benefiting from highly active and dense “hot spot” substrate, MNase-mediated cascade response strategy, and colorimetric/SERS dual-signal output, this methodology will offer a promising avenue for the early diagnosis of S. aureus infection.