Background: Propofol is a common sedative-hypnotic drug traditionally used for inducing and maintaining general anesthesia. Recent studies have drawn attention to the nonanesthetic effects of propofol, but the potential mechanism by which propofol suppresses non-small-cell lung cancer (NSCLC) progression has not been fully elucidated.
Methods: For the in vitro experiments, we used propofol (0, 2, 5, and 10 µg/mL) to treat A549 cells for 1, 4, and 12 hours and Cell Counting Kit-8 (CCK-8) to detect proliferation. Apoptosis was measured with flow cytometry. We also transfected A549 cells with an microribonucleic acid-21 (miR-21) mimic or negative control ribonucleic acid (RNA) duplex and phosphatase and tensin homolog, deleted on chromosome 10 (PTEN) small interfering ribonucleic acid (siRNA) or negative control. PTEN, phosphorylated protein kinase B (pAKT), and protein kinase B (AKT) expression were detected using Western blotting, whereas miR-21 expression was examined by real-time polymerase chain reaction (RT-PCR). In vivo, nude mice were given injections of A549 cells to grow xenograft tumors; 8 days later, the mice were intraperitoneally injected with propofol (35 mg/kg) or soybean oil. Tumors were then collected from mice and analyzed by immunohistochemistry and Western blotting.
Results: Propofol inhibited growth (1 hour, P = .001; 4 hours, P ≤ .0001; 12 hours, P = .0004) and miR-21 expression (P ≤ .0001) and induced apoptosis (1 hour, P = .0022; 4 hours, P = .0005; 12 hours, P ≤ .0001) in A549 cells in a time and concentration-dependent manner. MiR-21 mimic and PTEN siRNA transfection antagonized the suppressive effects of propofol on A549 cells by decreasing PTEN protein expression (mean differences [MD] [95% confidence interval {CI}], -0.51 [-0.86 to 0.16], P = .0058; MD [95% CI], 0.81 [0.07-1.55], P = .0349, respectively), resulting in an increase in pAKT levels (MD [95% CI] = -0.82 [-1.46 to -0.18], P = .0133) following propofol exposure. In vivo, propofol treatment reduced NSCLC tumor growth (MD [95% CI] = -109.47 [-167.03 to -51.91], P ≤ .0001) and promoted apoptosis (MD [95% CI] = 38.53 [11.69-65.36], P = .0093).
Conclusions: Our study indicated that propofol inhibited A549 cell growth, accelerated apoptosis via the miR-21/PTEN/AKT pathway in vitro, suppressed NSCLC tumor cell growth, and promoted apoptosis in vivo. Our findings provide new implications for propofol in cancer therapy and indicate that propofol is extremely advantageous in surgical treatment.