A glutathione activatable bioprobe for detection of hepatocellular carcinoma cells in peripheral blood via carbohydrate-protein interaction

Abstract

Due to high recurrence and metastasis rates leading to high mortality of hepatocellular carcinoma (HCC), detection of HCC circulating tumor cells (HCC-CTCs), which are regarded as an HCC blood marker, holds great significance in HCC early diagnosis, metastasis evolution, and prognosis. However, current existing circulating tumor cell (CTC) detection methods require multiple steps, and have low accuracy due to extremely rare CTCs in peripheral blood (PB). Thus, a simple and sensitive HCC-CTCs detection method is urgently needed. Here, a glutathione (GSH) activatable bioprobe (LacCC) targeting HCC cells was first developed through coordinating copper ions (Cu2+) to lactose modified coumarin derivative (LacC). Owing to the carbohydrate-protein interaction between lactose group and asialoglycoprotein receptors (ASGPRs) overexpressed on the membrane of HCC cells, LacCC displays selectivity towards HCC cells. The fluorescence of LacCC recovers rapidly within 2 min upon demetallation by high concentration of GSH in HCC cells. In simulated PB samples, as low as 10 HepG2 cells were detected via CLSM after removing red blood cells (RBCs) and culturing with LacCC. By coupling with flow cytometry, LacCC can achieve quantitative detection of HCC cells with low detection limit (LOD) of 3 cells per sample. Thus, this bioprobe possessing ASGPRs targetability and fast GSH responsiveness shows ultrasensitive detectability towards HCC cells in PB, which may have the potential for simple yet highly sensitive HCC-CTCs detection.