Jing Zhang

Now cisplatin and its analogs are some of the most effective chemotherapeutic agents in clinical use as the first line of treatment in testicular and ovarian cancers. Unfortunately, they have several major drawbacks, such as cumulative toxicities of nephrotoxicity and ototoxicity, inherent or treatment-induced resistance. This has provided the motivation for developing novel metal complexes as anticancer agents with different mechanism of action. In recent years, significant attention has been devoted to the role of G-quadruplexes in cancer. It was found that the stabilization of G-quadruplexes by small molecules has been shown to inhibit the transcriptional activity of some oncogenes. Thus, the G-quadruplex motif has emerged as a promising target for the design of selective anticancer drugs. Apart from the purely organic heteroaromatic compounds reported as G-quadruplex binders, it has recently been shown that metal complexes can also interact strongly and selectively with quadruplex DNA and have potential anticancer activity. This review will highlight recent progress of the metal complexes as anticancer drugs targeting G-quadruplex DNA, and discuss their future potential in the medical fields. Considering the significant roles of the metal ions, the metal complexes will be discussed as follows: (1) Ruthenium(II) complexes; (2) Nickel(II) complexes; (3) Zinc(II) complexes; (4) Manganese(III) complexes; (5) Copper(II) complexes; (6) Palladium(II)/Platinum(II); (7) Other metal complexes.

BACKGROUND AND OBJECTIVE: Beauvericin (BEA), a cyclic hexadepsipeptide mycotoxin, is a potent inhibitor of the acyl-CoA: cholesterol acyltransferase enzyme 1 (ACAT1), involved in multiple tumor-correlated pathways. However, the binding mechanisms between BEA and ACAT1 were not elucidated. METHODS: BEA was purified from a mangrove entophytic Fusarium sp. KL11. Single-crystal X-ray diffraction was used to determine the structure of BEA. Wound healing assays of BEA against KB cell line and MDA-MB-231 cell line were evaluated. Inhibitory potency of BEA against ACAT1 was determined by ELISA assays. Molecular docking was carried out to illuminate the bonding mechanism between BEA and ACAT1. RESULTS: The structure of BEA was confirmed by X-ray diffraction, indicating a monoclinic crystal system with P21 space group (α = 90°, β = 92.2216(9)°, γ= 90°). BEA displayed migration-inhibitory activities against KB cells and MDA-MB-231 cells In Vitro. ELISA assays revealed that the protein expression level of ACAT1 in KB cells was significantly decreased after BEA treatment (P ＜0.05). Molecular docking demonstrated that BEA formed hydrogen bond with His425 and pi-pi staking with Tyr429 in ACAT1. CONCLUSION: BEA sufficiently inhibited the proliferation and migration of KB cells and MDA-MB-231 cells by downregulating ACAT1 expression. In addition, BEA potentially possessed a strong binding affinity with ACAT1. BEA may serve as a potential lead compound for the development of a new ACAT1-targeted anticancer drug.