VEGFR-2 kinase domain inhibition as a scaffold for anti-angiogenesis: Validation of the anti-angiogenic effects of carotenoids from Spondias mombin in DMBA model of breast carcinoma in Wistar rats

Damilohun Samuel Metibemu; Oluseyi Adeboye Akinloye; Adio Jamiu Akamo; Jude Ogechukwu Okoye; David Ajiboye Ojo; Eric Morifi; Idowu Olaposi Omotuyi

doi:10.1016/j.toxrep.2021.02.011

VEGFR-2 kinase domain inhibition as a scaffold for anti-angiogenesis: Validation of the anti-angiogenic effects of carotenoids from Spondias mombin in DMBA model of breast carcinoma in Wistar rats

Toxicol Rep. 2021 Feb 25:8:489-498. doi: 10.1016/j.toxrep.2021.02.011. eCollection 2021.

Authors

Damilohun Samuel Metibemu^{1

2}, Oluseyi Adeboye Akinloye², Adio Jamiu Akamo², Jude Ogechukwu Okoye³, David Ajiboye Ojo⁴, Eric Morifi⁵, Idowu Olaposi Omotuyi¹

Affiliations

¹ Department of Biochemistry, Adekunle Ajasin University, Akungba-Akoko, Ondo State, Nigeria.
² Department of Biochemistry, Federal University of Agriculture, Abeokuta, Nigeria.
³ Department of Medical Laboratory Science, Faculty of Health Sciences and Technology, College of Medicine, Nnamdi Azikiwe University, Nnewi Campus, Nigeria.
⁴ Department of Microbiology, Federal University of Agriculture, Abeokuta, Nigeria.
⁵ Department of Chemistry, School of Chemistry, University of the Witwatersrand, Johannesburg, South Africa.

Abstract

Vascular endothelial growth factor (VEGF) and its receptor-2 (VEGFR-2) mediated tumorigenesis, metastasis, and angiogenesis are the cause of the increased levels of mortality associated with breast cancer and other forms of cancer. Inhibition of VEGF and VEGFR-2 provides a great therapeutic option in the management of cancer. This study employed VEGFR-2 kinase domain inhibition as an anti-angiogenic scaffold and further validate the anti-angiogenic effects of the lead phytochemicals, carotenoids from Spondias mombin in 7, 12-Dimethylbenz[a]anthracene (DMBA) model of breast carcinoma in Wistar rats. Phytochemicals characterized from 6 reported anti-cancer plants were screened against the VEGFR-2 kinase domain. The lead phytochemicals, carotenoids from Spondias mombin were isolated and subjected to Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (LC-ESI-MS) for characterization. The anti-angiogenic potentials of the carotenoid isolates were validated in the DMBA model of breast carcinoma in female Wistar rats through assessment of the expression of anti-angiogenic related mRNAs, histopathological analysis, and molecular docking. Treatment with carotenoid isolates (100 mg/kg and 200 mg/kg) significantly (p < 0.05) downregulated the expression of VEGF, VEGFR, Epidermal Growth Factor Receptor (EGFR), Hypoxia-Inducible Factor-1(HIF-1), and Matrix Metalloproteinase-2 (MMP-2) mRNAs in the mammary tumours, while the expression of Chromodomain Helicase DNA-Binding Protein-1 (CHD-1) mRNA was significantly (p < 0.05) upregulated. DMBA induced comedo and invasive ductal subtypes of breast carcinoma. The binding of astaxanthin, 7,7',8,8'-tetrahydro-β,β-carotene, and beta-carotene-15,15'-epoxide to the ATP binding site led to the DFG-out conformation with binding energies of -8.2 kcal/mol, -10.3 kcal/mol, and -10.5 kcal/mol respectively. Carotenoid isolates demonstrated anti-angiogenic and anti-proliferating potentials via VEGFR-2 kinase domain inhibition.

Keywords: 7, 12-Dimethylbenz[a]anthracene (DMBA); Angiogenesis; DFG-out conformation; Liquid Chromatography-Electrospray Ionization-Mass Spectrometry (LC-ESI-MS); Spondias mombin; VEGFR-2.