No abstract

Rapid tumor growth is dependent on the capability of tumor blood vessels and glycolysis to provide oxygen and nutrients. Tumor hypoxia is a common characteristic of many solid tumors, and it essentially happens when the growth of the tumor exceeds the concomitant angiogenesis. Hypoxia-inducible factor 1 (HIF-1) as the critical transcription factor in hypoxia regulation is activated to adapt to this hypoxia situation. Flavonoids, widely distributed in plants, comprise many polyphenolic secondary metabolites, possessing broadspectrum pharmacological activities, including their potentiality as anticancer agents. Due to their low toxicity, intense efforts have been made for investigating natural flavonoids and their derivatives that can be used as HIF-1α inhibitors for cancer therapy during the past few decades. In this review, we sum up the findings concerning the inhibition of HIF-1α by natural flavonoids in the last few years and propose the idea of designing tumor vascular and glycolytic multi-target inhibitors with HIF-1α as one of the targets.

No abstract

Simultaneous targeting of tumor vasculature and inhibitors of tumor cell glycolysis may be a promising antitumor strategy. Here, we reported the total synthesis and biological evaluation of A-ring arylurea flavonoid derivatives with B-ring trimethoxy group, which exhibited potent antitumor activity against a variety of tumor cells in vitro. Most of the derivatives showed in vitro antitumor activity on HepG-2, HGC-27, MDA-MB-231, and A549 cells. Among them, compounds 8e, 8f, 8g, 8h, 8j, and 8l also exhibited significant anti-proliferation effects on liver tumor cell subtypes BEL-7402 and SMMC-7721. Compound 8l had the lowest IC 50 value (5.61 ± 0.39 μM) on HepG-2 cells, and showed the effects of inhibiting colony formation, arresting the cell cycle in G 0 /G 1 phase, and inducing apoptosis in a concentration-dependent manner. In addition, the toxicity of compound 8l on human normal cells LO2 and GES-1 was lower than that of sorafenib. The inhibitory effects of compound 8l on the expression of glycolytic rate-limiting enzymes HKII, PFK-1, PKM2 and vascular endothelial growth factor were further evaluated.Corresponding reduction in intracellular lactate was also detected after compound 8 treatment. Our results support an antitumor strategy targeting tumor vasculature and glycolysis to discover and develop a new generation of antitumor drugs.