Antiproliferative effect of a novel synthesized carbazole compound on A549 lung cancer cell line.
Increased death rates due to lung cancer have necessitated the search for potential novel anticancer compounds such as carbazole derivatives. Carbazoles are aromatic heterocyclic compounds with anticancer, antibacterial and anti-inflammatory activity. The study investigated the ability of the novel carbazole compound (Z)-4-[9-ethyl-9aH-carbazol-3-yl) amino] pent-3-en-2-one (ECAP) to inhibit the proliferation of lung cancer cells and its mechanism of action. ECAP was synthesized as a yellow powder with melting point of 240-247 °C. The 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), lipid peroxidation and comet assays were used to assess the anti-proliferative effects of the compound on A549 lung cancer cell line. Protein expression was determined using western blots, apoptosis was measured by luminometry for caspase-3/7, -8 and -9 and flow cytometry was used to measure phosphatidylserine externalisation. ECAP induced a p53 mediated apoptosis of lung cancer cells by significantly down-regulating the expression of antioxidant defense proteins, Hsp70 (p < 0.02) and Bcl-2 (p < 0.0006), thereby up-regulating reactive oxygen species (ROS) production. This resulted in DNA damage (p < 0.0001) and subsequent up-regulation of Bax and caspase activity consequently inducing apoptosis of lung cancer cells. These results demonstrate the potential anticancer effects of ECAP on cultured lung cancer cells. However, further investigation and characterization is required to fully understand the possible use of carbazole compound (Z)-4-[9-ethyl-9aH-carbazol-3-yl) amino] pent-3- en-2-one as potential lung cancer treatment.