A Spatially Ordered Three-Input Logic Gate for Highly Specific and Sensitive Breast Tumor Imaging

Breast cancer poses a significant threat to the health of women globally. To date, clinically invasive needle biopsy may cause cancer metastasis, and noninvasive imaging methods exhibit suboptimal sensitivity. Therefore, developing a highly specific and sensitive diagnostic method for breast cancer detection continues to be a challenge. In this work, a spatially ordered three-input logic gate KK(GGR)-Luc is rationally designed to achieve precise and sensitive breast cancer in vivo imaging. The as-designed KK(GGR)-Luc can sequentially respond to urokinase-type plasminogen activator (uPA), cathepsin B (CTB), and luciferase (fLuc), and consequently, it generates highly specific bioluminescence (BL) signals in the 4T1 cells and tumors. Experimental results showed that the signal intensities of breast cancer treated with KK(GGR)-Luc exceeded those of all negative control groups by 3.5-fold in living cells and 5.0-fold in vivo, respectively. In addition, this spatially ordered three-input logic gate provided a long BL half-life (t1/2 = 117.2 min) in cells, which showed great potential in breast cancer in vivo imaging. We hope that the proposed sequentially activated three-input logic gate will aid in achieving highly precise and sensitive diagnosis of breast cancer in clinic.