Alpinumisoflavone against cancer pro-angiogenic targets: In silico, In vitro, and In ovo evaluation

Breast cancer is currently the world's most predominant malignancy. In cancer progression, angiogenesis is a requirement for tumor growth and metastasis.Alpinumisoflavone (AIF), a bioactive isoflavonoid, exhibited good binding affinity with the angiogenesis pathway's druggable target through molecular docking.

To confirm AIF's angiogenesis inhibitory activity, cytotoxic potential toward breast cancer cells, and druggability.

Antiangiogenic activity was evaluated in six pro-angiogenic proteins in vitro, duck chorioallantoic membrane (CAM) in ovo, molecular docking and druggability in silico.

Findings showed that AIF significantly inhibited (p =  < 0.001) the HER2(IC₅₀ = 2.96 µM), VEGFR-2(IC₅₀ = 4.80 µM), MMP-9(IC₅₀ = 23.00 µM), FGFR4(IC₅₀ = 57.65 µM), EGFR(IC₅₀ = 92.06 µM) and RET(IC₅₀ =  > 200 µM) activity in vitro.AIF at 25 µM-200 µM significantly inhibited (p =  < 0.001) the total number of branch points (IC₅₀ = 14.25 μM) and mean length of tubule complexes (IC₅₀ = 3.52 μM) of duck CAM comparable (p =  > 0.001) with the positive control 200 µM celecoxib on both parameters.AIF inhibited the growth of the estrogen-receptor-positive (ER +) human breast cancer cells (MCF-7) by 44.92 ± 1.79% at 100 µM while presenting less toxicity to human dermal fibroblast neonatal (HDFn) normal cells.The positive control 100 µM doxorubicin showed 86.66 ± 0.93% and 92.97 ± 1.27% inhibition with MCF-7 (IC₅₀ = 3.62 μM) and HDFn, (IC₅₀ = 27.16 μM) respectively.In docking, AIF has the greatest in silico binding affinity on HER2 (-10.9 kcal/mol) among the key angiogenic molecules tested. In silico rat oral LD₅₀ calculation indicates that AIF is moderate to slightly toxic at 146.4 mg/kg with 1.1 g/kg and 20.1 mg/kg upper and lower 95% confidence limits. Lastly, it sufficiently complies with Lipinski's, Veber's, Egan's, Ghose's, and Muegge's Rule, supporting its oral drug-like property.

This study revealed that AIF possesses characteristics of a phytoestrogen compound with significant binding affinity, inhibitory activity against pro-angiogenic proteins, and cytotoxic potential against ER + breast cancer cells.The acceptable and considerable safety and drug-likeness profiles of AIF are worthy of further confirmation in vivo and advanced pre-clinical studies so that AIF can be elevated as a promising molecule for breast cancer therapy.