Frontiers in Bioengineering and Biotechnology (Nov 2022)

A cascading-response fluorescent probe for real-time pH monitoring during cysteine-depletion process in pancreatic cancer cells

  • Xue Qin,
  • Shuping Zhang,
  • Xiaolu Guo,
  • Xingyue Liu,
  • Xing-Can Shen

DOI
https://doi.org/10.3389/fbioe.2022.1062781
Journal volume & issue
Vol. 10

Abstract

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Pancreatic cancer (PC) is one of the deadliest human malignancies, and exploring the complex molecular mechanisms behind cell death will greatly promote the clinical treatment of PC. Here, we reported a cascading-response fluorescent-imaging probe, Cy-Cys-pH, for the sequential detection of cysteine (Cys) and pH in pancreatic cancer cells. In the presence of Cys, Cys-mediated cleavage of the acrylate group caused Cy-Cys-pH to be transformed into Cy-Cys-O, which induced intense fluorescence enhancement at 725 nm. Then, Cy-Cys-O was protonated to obtain Cy-Cys-OH and the fluorescence emission shifted to 682 nm, showing a ratiometric pH response. Furthermore, Cy-Cys-pH can monitor the intracellular pH during the therapeutic process with anticancer drugs and evaluated the ability of three anticancer drugs to kill Panc-1 cells, proving that associating Cys and pH is in part an effective anticancer strategy in the treatment of pancreatic cancer. Significantly, Cy-Cys-pH is able to monitor and image pH changes during Cys depletion in real-time, which further reveals the molecular mechanism of Cys-depleted pancreatic cancer cell death, providing a powerful molecular tool for the precise treatment of PC.

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