Inhibition Of Chloroquine On The Proliferation Of A549 Cells

Objective:To investigate the inhibitory effect of chloroquine (CQ) on the proliferation ofhuman lung cancer cell line A549, and the role of Phosphatidylcholine-specificPhospholipase C ( PC-PLC ) in the processes of vacuolation, apoptosis, andnecrosis induced by CQ in A549 cells.Methods:A549 cells were cultured in vitro at a series of concentrations (0.25 μmol/L~128μmol/L) of chloroquine (CQ) for 0 ~ 72 hours.1. The morphological changes were observed undeF phase contrast microscope.2. The cell proliferation was measured by MTT assay.3. The lysossomal vacuolation degree-the volume of acidic compartments (VAC) was measured by neutral red uptake method.4. The cell apoptosis was assessed by acridine orange staining, and the neuclear morphological changes were observed under a fluorescence microscope.5. Cell necrosis was measured by lactate dehydrogenase (LDH) release assay.6. The role of PC-PLC was assessed with its specific inhibitor D609. Results:1. At lower concentrations (from 0.25 to 32 μmol/L), CQ inhibited the growth of A549 cells and, at the same time, it induced vacuolation with increased VAC.2. At higher concentration's (64-128 μmol/L), CQ induced apoptosis at 24 hour, while its effect of inducing vacuolation declined.3. The LDH assay showed that with the treatment of CQ 32-64 umol/L for 72 hours or 128 μmol/L for 48 hours, CQ induced necrosis of A549 cells.4. D609. (50 umol/L) could inhibit the effects of CQ 32 μmol/L on the viability and VAC of A549 cells, but it could not change the effects of CQ 128 μmol/L...