Design and synthesis of novel hexahydrobenzo[4,5]thieno[2,3‐d]pyrimidine derivatives as potential anticancer agents with antiangiogenic activity via VEGFR‐2 inhibition, and down‐regulation of PI3K/AKT/mTOR signaling pathway

Abstract

AbstractNew thieno[2,3‐d]pyrimidine derivatives were designed and synthesized. The National Cancer Institute (NCI) evaluated the synthesized novel compounds against a panel of 60 tumor cell lines for their antiproliferative activity. Compounds 6b, 6f, and 6g showed potent anticancer activity at 10 µM dose, with mean GI of 20.86%, 76.41%, and 31.49%, respectively. Compound 6f was selected for five‐dose concentrations evaluation. Compound 6f scored a submicromolar range of GI50 values against 10 cancer cell lines, indicating broad‐spectrum and potent antiproliferative activity. Compound 6f TGI values were recorded in the cytostatic range of 4.02–95.1 µM. In comparison to sorafenib, the tested compounds 6b, 6f, and 6g inhibited VEGFR‐2 with IC50 values of 0.290 ± 0.032, 0.066 ± 0.004, and 0.16 ± 0.006 µM, correspondingly. Compound 6f significantly reduced the total VEGFR‐2 expression and its phosphorylation. Additionally, 6f reduced the phosphorylation of PI3K, Akt, and mTOR pathway proteins. Moreover, the migratory potential of HUVECs was significantly reduced, after 72 h of treatment with compound 6f, resulting in disrupted wound healing patterns which verified the angiogenesis suppression properties of compound 6f. Compound 6f increased the total apoptosis percentage by 21.27‐fold compared to sorafenib, which caused a 24.11‐fold increase in the total apoptosis percentage. This apoptotic activity was accompanied by a 7.81‐fold increase in the level of apoptotic caspase‐3. Furthermore, the cell cycle analysis revealed that the target derivative 6f reduced cellular proliferation and induced an arrest in HCT‐15 colon cancer cell cycle at the S phase. Molecular modeling was used to determine the binding profile and affinity of derivative 6f toward the VEGFR‐2 active site.