Discovery of Turn-On Fluorescent Probes for Detecting Bcl‑2 Protein

B-cell-lymphoma-2-gene (Bcl-2) family proteins play a central role in regulating programmed cell death. In cancer, antiapoptotic Bcl-2 proteins, such as Bcl-2 and Mcl-1, are overexpressed. However, there are few developed labeling techniques for tracing the dynamic processes of Bcl-2. To study the physiological process of Bcl-2 protein, a novel series of small-molecule fluorescent probes (1–3) were designed and evaluated for their labeling properties. Our probes can be applied to the identification of tumor-tissue slices and the differentiation of tumor and normal tissues effectively, a feature that renders these probes compatible with future cancer diagnosis in clinical practice.