Selected novel 5’-amino-2’-hydroxy-1, 3-diaryl-2- propen-1-ones arrest cell cycle of HCT-116 in G₀/G₁ phase

A series of 5’-amino-2’-hydroxy-1,3-diaryl-2-propen-1-ones (AC1-AC15) were synthesized by Claisen-Schmidt condensation of 5'-acetamido-2’-hydroxy acetophenone with various substituted aromatic aldehydes. The syn- thesized compounds were characterized by FTIR, 1H NMR and mass spectrometry and evaluated for their selec- tive cytotoxicity using MTT assay on two cancer cell lines namely breast cancer cell line (MCF-7), colon cancer cell line (HCT-116) and one normal kidney epithelial cell line (Vero). Among the tested compounds, AC-10 showed maximum cytotoxic effect on MCF-7 cell line with IC₅₀ value 74.7 ± 3.5 µM. On HCT-116 cells, AC-13 exhibited maximum cytotoxicity with IC₅₀ value 42.1 ± 4.0 µM followed by AC-14 and AC-10 with IC₅₀ values 62 ± 2.3 µM and 95.4 ± 1.7 µM respectively. All tested compounds were found to be safe on Vero cell line with IC50 value more than 200 µM. Based on their highest efficacy on HCT-116, AC-10, AC-13 and AC-14 were selected for mechanistic study on this cell line by evaluating changes nucleomorphological characteristics using acridine orange-ethidium bromide (AOEB) dual stain and by analyzing cell cycle with flow cytometry using propidium iodide stain. In AOEB staining, all three tested compounds showed significant (p < 0.05) increase in percentage apoptotic nuclei compared to control cells, with highest increase in apoptotic nuclei by AC-13 treatment (31%). Flow cytometric studies showed cell cycle arrest by AC-10 and AC-14 treatment in G₀/G₁ phase and by AC-13 in G₀/G₁ and G₂/M phase. The study reflected the potential of AC-10, AC-13 and AC-14 to be the lead molecules for further optimization.