Determination Of Cancer Cells Induced By Secretagogues Based On Fluorescence Resonance Energy Transfer

Cancer cells secrete copious amounts of secretory granules, exosomes, proteases. Recently, studies reviewed that mast cells (MCs) play crucial roles in the growth, spread and metastasis of tumor. MCs are one of the earliest cell types to infiltrate developing tumors. MCs undergo degranulation in response to various stimuli and rapidly release diverse bioactive mediators, such as histamine, tryptase, serotonin, tumor necrosis factor alpha (TNF alpha), which will tremendously affect the tumor microenvironment (TME). However, the mechanisms between the secretion of MCs degranulation and tumor remain unclear. Therefore, we developed a nanobiosensor based on fluorescence resonance energy transfer (FRET) for the determination of P815 mast cells and HeLa cells by secretagogues. With the pep-FITC as an energy donor and reduced grapheme oxide (rGO) as an energy acceptor, the two parts assemble an efficient FRET biosensor through electrostatic and stacking interaction (pi-pi interaction). Sensitized secretory cells can produce tryptase which would hydrolyze the specific cleavage site of the peptide, leading to ruin FRET system and then yield intensive fluorescence (FL) recovery of quenched FITC. Results showed that P815 cells are more sensitive and intense secretory than HeLa cells owing to more amount secretory mediators of P815 can change the microenvironment and further exacerbate the degree of degranulation in return. Our findings suggest that FRET biosensor have the ability to detect the extracellular dynamics of the cancer cells microenvironment. In addition, targeting mast cells may serve as a novel therapeutic scheme for cancer treatment and that inhibiting mast cell function may lead to tumor regression.