Comparative Evaluation of Antiproliferative Activity and Induction of Apoptosis by some Fluoroquinolones on a Human Non-small Cell Lung Cancer Cell Line in Culture

Lung cancer is the leading cause of cancer- related death in the world today. Since the effective management of ‍drug resistant lung cancer, and particularly non-small cell lung carcinomas is a major problem, attempts need to be ‍made to identify new potential anticancer drugs that can kill non-small cell lung cancer cells efficiently. In the ‍present study, a human non-small cell lung carcinoma NCI-H460 cell line was used to evaluate the antiproliferative ‍activity of Fluoroquinolones like Enoxacin, Norfloxacin, Ciprofloxacin and Levofloxacin. As determined by ‍Sulphorodhamine B assay (SRB assay), all Fluoroquinolones caused cellular growth inhibition in a concentration ‍and time-dependent manner. Enoxacin was found to be the most effective Fluoroquinolone followed by Norfloxacin, ‍Ciprofloxacin and Levofloxacin. Growth inhibitory effects were also found to be independent of the concentrations ‍of serum growth factors in culture medium or variation of initial cell seeding density and proved to be irreversible in ‍nature. Appearance of rounded cells with altered morphology and cell surface blebbing indicated cell killing by ‍apoptosis. Cell shrinkage, nuclear condensation & fragmentation, and cytoplasmic blebbing as indicated by MGG ‍staining confirmed this to be the case. Thus, this investigation clearly demonstrated that the NCI-H460 human nonsmall ‍cell lung carcinoma cell line is highly sensitive to Fluoroquinolone treatment. The Fluoroquinolones used in ‍this study which are clinically used as antibacterial agents, can also inhibit tumor cell growth suggesting their potential ‍use in a strategy for cancer treatment which might help in controlling cancer.