Tricetin is a type of flavonoid that plays an important role in anti-cancer activity. However, the protein targets and function mechanism of tricetin in HepG2 cells remain unclear, which greatly limits its clinical application. In this paper, tricetin was immobilized by 3D photo cross linking chip and the microfluidic environment was established. The SPR (surface plasmon resonance) technique was used to monitor the protein targets interacting with the tricetin on the surface of the chip. The target proteins captured by tricetin in HepG2 cell were identified by HPLC-MS (high performance liquid chromatography-mass pec trometry) method. Bioinformatics annotation and analysis of the obtained proteins showed that the VDR (vitamin D receptor) and PIM1 (Ser/Thr-protein kinase-1) were significantly enriched in the vitamin D receptor signalling pathway (Rich factor > 0.6), and thirty high affinity proteins mainly involved in pathways in Cancer, MAPK (mitogenactivated protein kinase) signalling pathway, TNF (tumour necrosis factor) signalling pathway, Osteoclast differentiation. Among them, four high score affinity target proteins, CYP1B1 (cytochrome P4501B1), VDR, PIM1 and GAA were screened by reverse molecular docking. Finally, the two target proteins, VDR and PIM1, which provided important theoretical support for tricetin in anti-liver cancer research were fully discussed.

Volume 4 -Issue 1 SA is widely used as a model protein for the investigation of protein surface binding and drug binding mechanisms because of its unique microenvironment (~seven hydrophobic grooves on its surface), and because it acts as a universal receptor for many drug molecules [10,11]. Both BSA and HSA are studied extensively side by side for protein-protein or protein-drug interaction because of their 76% similar structural sequence homology (583 and 585 amino acid residues respectively) [12]. They both are a single chain globular protein containing three structurally homologues domains, I, II and III along with two sub-domains (A and B) within each. Two specific drug binding sites were identified in the hydrophobic cavities in the sub-domains, known as sites I (in subdomain IIA) and II (in subdomain IIIA) of albumin [13][14][15]. Protein fluorescence originates from amino acid residues such as tryptophan, tyrosine and phenylalanine present at these sites or from the fluorescence of the bound drug molecule itself. In BSA, the two dominant fluorescence sites are Trp 134 located on the surface of sub-domain IB, and Trp 212 located within the hydrophobic pocket of sub-domain IIA. The amino acids responsible for its intrinsic fluorescence in HSA are Trp 214 (most dominant) which resides in sub-domain IIA, and several tyrosine residues located in different sub-domains [14][15][16].Fluorescence spectroscopy is a commonly used analytical technique in the study of interactions between drugs and serum albumin because