Apoptosis of Lewis Lung Carcinoma Cells Induced by Microwave via p53 and Proapoptotic Proteins In vivo

Background： Microwave therapy is a minimal invasive procedure and has been employed in clinical practice for the treatment of various types of cancers. However, its therapeutic application in non-small-cell lung cancer and the underlying mechanism remains to be investigated. This study aimed to investigate its effect on Lewis lung carcinoma （LLC） tumor in vivo. Methods： Fifty LLC tumor-bearing C57BL/6 mice were adopted to assess the effect of microwave radiation on the growth and apoptosis of LLC tumor in vivo. These mice were randomly assigned to 10 groups with 5 mice in each group. Five groups were treated by single pulse microwave at different doses for different time, and the other five groups were radiated by multiple-pulse treatment of a single dose. Apoptosis of cancer cells was determined by terminal deoxynucleotidyl transferase dUTP nick-end labeling assay. Western blotting was applied to detect the expression of proteins. Results： Single pulse of microwave radiation for 5 min had little effect on the mice. Only 15-min microwave radiation at 30 mW/cm2 significantly increased the mice body temperature （2.20 ± 0.82）℃ as compared with the other groups （0.78 ± 0.29 ℃, 1.24 ± 0.52 ℃, 0.78 ± 0.42 ℃, respectively）, but it did not affect the apoptosis of LLC tumor cells significantly. Continous microwave radiation exposure, single dose microwave radiation once per day for up to seven days, inhibited cell division and induced apoptosis of LLC tumor cells in a dose- and duration-dependent manner. It upregulated the protein levels of p53, Caspase 3, Bax and downregulated Bcl-2 protein. Conclusions： Multiple exposures of LLC-bearing mice to microwave radiation effectively induced tumor cell apoptosis at least partly by upregulating proapoptotic proteins and downregulating antiapoptotic proteins. Continuous radiation at low microwave intensity Ibr a short time per day is promising in treating non-small-cell lung cancer.

Herbal formula Renshenwuweizi decoction induces p53-mediated cell cycle arrest and apoptosis in A549 cells

OBJECTIVE:To investigate the effect of Renshenwuweizi decoction(RSWWZ decoction)on the growth of non-small cell lung cancer cells in vitro.METHODS:A549 non-small cell lung cancer cells were divided into two groups:control and RSWWZ decoction treatment groups.Cell Counting Kit-8 was used to measure the inhibitory effect of RSWWZ decoction on the growth of A549 cells.4’,6-diamidino-2-phenylindole staining and Annexin V-fluorescein isothiocyanate/propidium iodide double staining were used to investigate apoptosis in A549 cells following RSWWZ decoction treatment,and the mitochondrial membrane potential of treated cells was detected with Rhodamine 123.Cell cycle progression was analyzed by flow cytometry.The m RNA levels of p53,Bax,B-cell lymphoma-2(Bcl-2)and p21 were measured by quantitative real-time reverse transcription polymerase chain reaction.The protein expressions of p53,Bax,Bcl-2,p21,cyclin-dependent kinases 2(CDK2),and cyclin A were detected by Western blot.RESULTS:RSWWZ decoction reduced the viability of A549 cells in a dose-dependent manner by inducing apoptosis and decreased mitochondrial membrane potential.RSWWZ decoction increased p53 and Bax expression and decreased Bcl-2 expression in a dose-dependent manner.RSWWZ decoction also induced an S-phase cell cycle arrest by increasing p21 and decreasing cyclin A and CDK2 expression.CONCLUSION:In vitro experiments revealed that the Renshenwuweizi decoction-induced decrease in A549 cell proliferation was achieved by inducing apoptosis and S-phase cell cycle arrest via the p53 pathway.These findings provide the experimental basis for Renshenwuweizi decoction treatment of lung cancer.