ABSTRACT
ETHNOPHARMACOLOGICAL RELEVANCE: Salvia miltiorrhiza Bunge, a well-known traditional Chinese medicinal (TCM) plant, has been used to treat cardiovascular diseases since thousands of years. Many studies reported that the active component tanshinones displayed a variety of biological activities: anti-thrombous, anti-allergic, anti-inflammatory, antioxidant and anti-tumor promoting. But the mechanism of how the active components working still need to be clarified. The anti-tumor effect of compounds of tanshinone (CTN), the methanol extract of Salvia miltiorrhiza Bunge roots, was investigated. The aim of this study was to investigate the effects of CTN on the growth inhibition, apoptosis and molecular targets of human non-small cell lung cancer (NSCLC). MATERIALS AND METHODS: CTN-induced cytotoxicity was determined by MTT assay. The cell survival was evaluated using clonogenic survival assay. The morphology of Glc-82 cells after treatment with CTN was determined by fluorescence microscopy. Cell cycle distribution was revealed by flow cytometry. The apoptotic cells were quantified with annexin V-FITC/PI staining and flow cytometry, and observed using Hoechst 33258 staining and TUNEL assays. The expression levels of proteins were analyzed using western blot. Tumor growth was assessed by subcutaneous inoculation of cells into BALB/c nude mice. RESULTS: CTN inhibited the proliferation of NSCLC in a dose-dependent manner and induced both early and late apoptosis. Treatment of Glc-82 cells with CTN (5-80µg/ml) significantly (p<0.05) suppressed the cell proliferation in a concentration and time-dependent manner. CTN induced significant (p<0.05) and dose-dependent apoptosis of Glc-82 cells. Cell cycle assay showed that CTN induced a G2/M phase arrest, and significantly (p<0.05) increased expression of p53 and p21, actived caspase-3/9 and PARP1, which suggest the involvement of the mitochondria in the apoptotic signals. In addition, CTN decreased expression of the anti-apoptotic protein Bcl-2, Bcl-xl and increased expression of the pro-apoptotic protein Bax. Result also showed that CTN could increase expression levels of PTEN, and reduce the phosphorylated levels of Akt (protein kinase B) on Thr 308 and Ser 473 domain. In vivo assay showed that the antitumor effect of CTN was significantly augmented without increasing toxicity in nude mice bearing Glc-82 xenograft. CONCLUSION: The PTEN/Akt signaling axis is defined as a critical pathway regulated by PTEN in NSCLC. CTN, the methanol extract of Salvia miltiorrhiza Bunge, are the active compounds as shown by their ability to induce apoptosis through the mitochondrial pathway of apoptosis and PTEN-mediated inhibition of PI3K/Akt pathway. CTN could inhibit tumor growth more efficiently, which supports the ethno-medicinal use of this herb as an alternative or complementary therapy for NSCLC.
Subject(s)
Carcinoma, Non-Small-Cell Lung/drug therapy , Lung Neoplasms/drug therapy , Oncogene Protein v-akt/antagonists & inhibitors , PTEN Phosphohydrolase/biosynthesis , Phosphoinositide-3 Kinase Inhibitors , Plant Extracts/therapeutic use , Salvia miltiorrhiza , A549 Cells , Animals , Antineoplastic Agents, Phytogenic/isolation & purification , Antineoplastic Agents, Phytogenic/pharmacology , Antineoplastic Agents, Phytogenic/therapeutic use , Apoptosis/drug effects , Apoptosis/physiology , Carcinoma, Non-Small-Cell Lung/metabolism , Cell Survival/drug effects , Cell Survival/physiology , Dose-Response Relationship, Drug , Humans , Lung Neoplasms/metabolism , Male , Methanol/pharmacology , Methanol/therapeutic use , Mice , Mice, Inbred BALB C , Mice, Nude , Oncogene Protein v-akt/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Plant Roots , Signal Transduction/drug effects , Signal Transduction/physiology , Xenograft Model Antitumor Assays/methodsABSTRACT
Hepatocellular carcinoma (HCC) is the most common tumor in worldwide and chemotherapy resistant is a severe obstacle in HCC treatment. Annonaceous acetogenins was a nature compound from Uvaria accuminata and it has show the anti-tumor proliferation activity in many types cancer. In this study, we showed that annonaceous acetogenins is correlated with the drug resistance reversal in human hepatocellular carcinoma BEL-7402/5-FU and HepG2/ADM cell lines. We found that cell apoptosis was improved and cell cycle was arrested, further, multidrug-resistance proteins such as MDR1, MRP1, Topo-IIα, GST-π, cyclin D1, Survivin and bcl-2 are down-regulated, however, intracellular Rh-123 and caspase-3/8 was up-regulated by Annonaceous acetogenins treatment. We also found that there was a decreased activity of NF-κB and Akt in Annonaceous acetogenins treatment groups. Therefore, we demonstrate that Akt/NF-κB pathway was involved in Annonaceous acetogenins reverses drug resistance of human hepatocellular carcinoma cells.
