A sensitive and fast responsive fluorescent probe for imaging hypoxic tumors.

Area of Science:

• Biomedical Imaging
• Molecular Probes
• Cancer Diagnostics

Background:

• Nitroreductase (NTR) activity correlates with tumor hypoxia, presenting a target for cancer detection.
• Developing sensitive and specific probes for NTR is essential for effective tumor imaging.

Purpose of the Study:

• To develop and characterize a novel nitroreductase-responsive fluorescent probe (BBP).
• To evaluate the probe's sensitivity, specificity, and response time for NTR detection.
• To assess the probe's utility in detecting tumors in various biological models.

Main Methods:

• Synthesis of a 2,5-bis(methylsulfinyl)-1,4-diaminobenzene based probe (BBP).
• In vitro testing for selectivity against other reductants and sensitivity down to 20 ng mL-1 NTR.
• Kinetic analysis of probe response to NTR.
• In situ imaging in 2D cell monolayers, 3D tumor spheroids, and solid tumors in mice.

Main Results:

• BBP demonstrated high sensitivity and specificity for NTRs, distinguishing them from other biological reductants.
• The probe detected as low as 20 ng mL-1 NTRs with a rapid response time of 10 minutes.
• BBP successfully visualized NTR activity in vitro and in vivo, including solid tumors in mice.

Conclusions:

• BBP is a highly sensitive and rapid nitroreductase-responsive fluorescent probe.
• The probe can identify NTR activity in diverse tumor models, aiding early tumor detection.
• BBP shows significant potential for clinical diagnostic and therapeutic applications in oncology.