Cryptotanshinone Inhibits Lung Tumorigenesis And Induces Apoptosis In Cancer Cells In Vitro And In Vivo

Objective: To detect the anti-tumor effect of cryptotanshinone by studying theeffects of cryptotanshinone on proliferation of human lung adenocarcinomaepithelial cell A549cells and xenotransplantation formation of human lung tumor onnude mice.Method:1. Human lung adenocarcinoma epithelial cell A549cells were seededand treated with cryptotanshinone. The MTT assay was performed to detect the cellgrowth for cytotoxicity test. Colony-forming assay was performed to detect the cellsurvival. Flow cytometry (FCM) was performed to detect the cell cycle. Theexpression of cell cycle and apoptosis related genes were tested using Realtime-PCRwhile Western Blot for cell cycle and apoptosis related protein detection.2. Humanlung tumor xenotransplantation was generated by subcutaneous injection of nudemice. Growth of mice and tumor formation were examined and the in vivoexpressions of apoptosis relative factors were tested using IHC.Results: In in vitro study, cryptotanshinone inhibits the growth and the colonyformation of human lung adenocarcinoma epithelial cells A549. Cryptotanshinonecould arrest the growth of A549cells at G2/M phase. CCNB1(cyclin B1), CDK1(CDC2) and CDC25C were down-regulated(<0.5fold) while the expression ofCDKN1A(p21CIP1/WAF1) was up-regulated(>2folds) using Real-time quantitativePCR. The expression of G2/M phase relative protein Cyclin B1, CDK1andCDC25C were down-regulated, while P21CIP1/WAF1was up-regulated aftertreatment of cryptotanshinone. For the apoptosis relative protein, the expression ofBcl-2was down-regulated while P53and Bax were up-regulated after treatment ofcryptotanshinone, indicating cryptotanshinone could induce and promote theapoptosis of A549cells. In in vivo study, the tumor size of xenotransplantation andthe body weight of nude mice was decreased much slower in cryptotanshinone group.Meanwhile, the physical and mental status in cryptotanshinone group seemed to bemuch better. Low density infiltration and low activity tumor were found incryptotanshinone group using HE staining for pathological detection. Increasedapoptosis cells were detected in cryptotanshinone group using TUNEL kit. P53, Baxand Caspase3were found increased, while Bcl-2was found decreased incryptotanshinone group compared with control.Conclusion: The effects of cryptotanshinone on growth-inhibitory of cells andtumors, cell cycle arrest, apoptosis and inhibition of tumor formation, improvementof nude mice growth condition and induction of tumor disintegration for human lungcancer both in vitro and in vivo study. Cryptotanshinone would be a potentialchemical for treatment and prevention of the human lung cancer.