The cell cycle profiles of both untreated and caffeine/cisplatin-treated HTB182 and CRL5985 lung cancer cells. Cells were either untreated or treated with caffeine (2 mM) and/or cisplatin (10 μM). The cells were collected 20 hours after the cisplatin treatment and used for flow cytometry assay. A propidium iodide-based DNA staining was used in the flow cytometry assay to stain DNA content in the fixed cells. The corresponding captions used in the panels: (A) untreated HTB182; (B) HTB182 treated with caffeine; (C) HTB182 treated with cisplatin; (D) HTB182 treated with both caffeine and cisplatin; (E) untreated CRL5985; (F) CRL5985 treated with caffeine; (G) CRL5985 treated with cisplatin; (H) CRL5985 treated with both caffeine and cisplatin.