Cancer:
Breast, leukemia, Oral cancer, renal cell carcinoma, colon

Action: Anti-inflammatory, tamoxifen resistance, cell-cycle arrest, anti-metastatic, MDR

Tetrandrine, a bisbenzylisoquinoline alkaloid from the root of Stephania tetrandra (S, Moore), exhibits a broad range of pharmacological activities, including immunomodulating, anti-hepatofibrogenetic, anti-inflammatory, anti-arrhythmic, anti-portal hypertension, anti-cancer and neuro-protective activities (Li, Wang, & Lu, 2001; Ji, 2011). Tetrandrine has anti-inflammatory and anti-fibrogenic actions, which make tetrandrine and related compounds potentially useful in the treatment of lung silicosis, liver cirrhosis, and rheumatoid arthritis (Kwan & Achike, 2002).

Tetrandrine generally presents its anti-cancer effects in micromolar concentrations. Tetrandrine induces different phases of cell-cycle arrest, depends on cancer cell types (Kuo & Lin, 2003; Meng et al., 2004; Ng et al., 2006) and also induces apoptosis in many human cancer cells, including leukemia, bladder, colon, hepatoma, and lung (Lai et al., 1998; Ng et al., 2006; Wu et al., 2010; He et al., 2011).

In vivo experiments have also demonstrated the potential value of tetrandrine against cancer activity. For example, the survival of mice subcutaneously inoculated with CT-26 cells is extended after daily oral gavage of 50 mg/kg or 150  mg/kg of tetrandrine (Wu et al., 2010). Tetrandrine also inhibits the expression of VEGF in glioma cells, has cytotoxic effect on ECV304 human umbilical vein endothelial cells, and suppresses in vivo angiogenesis (Chen et al., 2009). Tetrandrine-treated mice (10  mg/kg/day) have fewer metastases than vehicle-treated mice, and no acute toxicity or obvious changes can be observed in the body weight of both groups (Chang et al., 2004).

Leukemia

Tetrandrine citrate is a novel orally active tetrandrine salt with potent anti-tumor activity against IM-resistant K562 cells and chronic myeloid leukemia. Tetrandrine citrate-induced growth inhibition of leukemia cells may be involved in the depletion of p210Bcr-Abl mRNA and β-catenin protein (Xu et al., 2012).

Comparative in vitro studies show that tetrandrine has significantly greater suppressive effects on adherence, locomotion and 3H-deoxyglucose uptake of neutrophils, as well as the mitogen-induced lymphocyte responses and mixed lymphocyte reactions. By contrast, berbamine demonstrated a significantly greater capacity for inhibition of NK cell cytotoxicity. These results show that tetrandrine is superior to berbamine in most aspects of anti-inflammatory and immunosuppressive activity.

Since these two alkaloids differ by only one substitution in the side chain of one of the benzene rings, these findings may provide further insight into structure-activity relationships and clues to the synthesis and development of active analogues of this promising class of drugs for the treatment of chronic inflammatory diseases (Li et al., 1989).

MDR, Breast Cancer

Tetrandrine also has been found to have extensive pharmacological activity, including positive ion channel blockade and inhibition of multiple drug resistance proteins. These activities are very similar to that of salinomycin, a known drug targeting breast cancer initiation cells (TICs). Tetrandrine has been probed for this activity, targeting of breast cancer TICs. SUM-149, an inflammatory breast cancer cell line, and SUM-159, a non-inflammatory metaplastic breast cancer cell line, were used in these studies.

In summary, tetrandrine demonstrates significant efficacy against in vitro surrogates for inflammatory and aggressive breast cancer TICs (Xu et al., 2011).

Leukemia, MDR

The potential mechanism of the chemotherapy resistance in acute myeloid leukemia (AML) is the multi-drug resistance (MDR-1) gene product P-glycoprotein (P-gp), which is often overexpressed in myeloblasts from acute myeloid leukemia. In a multi-center clinical trial, 38 patients with poor risk forms of AML were treated with tetrandrine (TET), a potent inhibitor of the MDR-1 efflux pump, combined with daunorubicin (DNR), etoposide and cytarabine (TET–DEC). Overall, postchemotherapy marrow hypoplasia was achieved in 36 patients. Sixteen patients (42%) achieved complete remission or restored chronic phase, 9 achieved partial remission (PR) and 13 failed therapy.

These data indicate that TET–DEC was relatively well tolerated in these patients with poor risk AML, and had encouraging anti-leukemic effects (Xu et al., 2006).

Tamoxifen

Tetrandrine (Tet) had a significant reversal of tamoxifen drug resistance breast cancer cells resistant (MCF-7/TAM). The non-cytotoxic dose (0. 625 microg/mL) reversed the resistance by 2.0 folds. MRP1 was reduced at gene (P <0.05) and protein levels when Tet effected on MCF-7ITAM cells. Tet could reverse the drug resistance of MCF-7/TAM cells, and the reverse mechanism may be related to down-regulating MRP1 expression (Chen & Chen, 2013).

Colon Cancer

Tetrandrine (TET) exhibits anti-colon cancer activity. Gao et al. (2013) compared TET with chemotherapy drug doxorubicin in 4T1 tumor-bearing BALB/c mice model and found that TET exhibits anti-cancer metastatic and anti-angiogenic activities better than those of doxorubicin. Local blood perfusion of tumor was markedly decreased by TET after 3 weeks.

Mechanistically, TET treatment leads to a decrease in p-ERK level and an increase in NF- κ B levels in HUVECs. TET also regulated metastatic and angiogenic related proteins, including vascular endothelial growth factor, hypoxia-inducible factor-1 α, integrin β 5, endothelial cell specific molecule-1, and intercellular adhesion molecule-1 in vivo (Chen & Chen, 2013).

Tetrandrine significantly decreased the viability of SAS human oral cancer cells in a concentration- and time-dependent manner. Tet induced nuclear condensation, demonstrated by DAPI staining, and induces apoptosis and autophagy of SAS human cancer cells via caspase-dependent and LC3-I and LC3-II “American Typewriter”; “American Typewriter”;‑dependent pathways (Huang et al., 2013).

Renal Cancer

Tetrandrine treatment showed growth-inhibitory effects on human renal cell carcinoma (RCC) in a time- and dose-dependent manner. Additionally, flow cytometric studies revealed that tetrandrine was capable of inducing G1 cell-cycle arrest and apoptosis in RCC cells. Tet triggered apoptosis and cell-cycle arrest in RCC 786-O, 769-P and ACHN cells in vitro; these events are associated with caspase cascade activation and up-regulation of p21 and p27 (Chen, Ji, & Chen, 2013).

References

Chang KH, Liao HF, Chang HH, et al. (2004). Inhibitory effect of tetrandrine on pulmonary metastases in CT26 colorectal adenocarcinoma-bearing BALB/c mice. American Journal of Chinese Medicine, 32(6):863–872.

Chen HY, Chen XY. (2013). Tetrandrine reversed the resistance of tamoxifen in human breast cancer MCF-7/TAM cells: an experimental research. Zhongguo Zhong Xi Yi Jie He Za Zhi, 33(4):488-91.

Chen T, Ji B, Chen Y. (2013). Tetrandrine triggers apoptosis and cell-cycle arrest in human renal cell carcinoma cells. J Nat Med.

Chen Y, Chen JC, Tseng SH. (2009). Tetrandrine suppresses tumor growth and angiogenesis of gliomas in rats. International Journal of Cancer, 124(10):2260–2269.

Gao JL, Ji X, He TC, et al. (2013). Tetrandrine Suppresses Cancer Angiogenesis and Metastasis in 4T1 Tumor-bearing Mice. Evid Based Complement Alternat Med, 2013:265061. doi: 10.1155/2013/265061.

He BC, Gao JL, Zhang BQ, et al. (2011). Tetrandrine inhibits Wnt/beta-catenin signaling and suppresses tumor growth of human colorectal cancer. Molecular Pharmacology, 79(2):211–219.

Huang AC, Lien JC, Lin MW, et al. (2013). Tetrandrine induces cell death in SAS human oral cancer cells through caspase activation-dependent apoptosis and LC3-I and LC3-II activation-dependent autophagy. Int J Oncol, 43(2):485-94. doi: 10.3892/ijo.2013.1952.

Ji YB. (2011). Active Ingredients of Traditional Chinese Medicine: Pharmacology and Application, People's Medical Publishing House Co., LTD, 2011.

Kwan CY, Achike FI. (2002). Tetrandrine and related bis-benzylisoquinoline alkaloids from medicinal herbs: cardiovascular effects and mechanisms of action. Acta Pharmacol Sin, 23(12):1057-68.

Kuo PL and Lin CC. (2003). Tetrandrine-induced cell-cycle arrest and apoptosis in Hep G2 cells. Life Sciences, 73(2):243–252.

Lai YL, Chen YJ, Wu TY, et al. (1998). Induction of apoptosis in human leukemic U937 cells by tetrandrine. Anti-Cancer Drugs, 9(1):77–81.

Li SY, Ling LH, The BS, Seow WK and Thong YH. (1989). Anti-inflammatory and immunosuppressive properties of the bis-benzylisoquinolines: In vitro comparisons of tetrandrine and berbamine. International Journal of Immunopharmacology, 11(4):395-401 doi:10.1016/0192-0561(89)90086-6.

Meng LH, Zhang H, Hayward L, et al. (2004). Tetrandrine induces early G1 arrest in human colon carcinoma cells by down-regulating the activity and inducing the degradation of G 1-S-specific cyclin-dependent kinases and by inducing p53 and p21Cip1. Cancer Research, 64(24):9086–9092.

Ng LT, Chiang LC, Lin YT, and C. C. Lin CC. (2006). Anti-proliferative and apoptotic effects of tetrandrine on different human hepatoma cell lines. American Journal of Chinese Medicine, 34(1):125–135.

Wu JM, Chen Y, Chen JC, Lin TY, Tseng SH. (2010). Tetrandrine induces apoptosis and growth suppression of colon cancer cells in mice. Cancer Letters, 287(2):187–195.

Xu WL, Shen HL, Ao ZF, et al. (2006). Combination of tetrandrine as a potential-reversing agent with daunorubicin, etoposide and cytarabine for the treatment of refractory and relapsed acute myelogenous leukemia. Leukemia Research, 30(4):407-413.

Xu W, Debeb BG, Lacerda L, Li J, Woodward WA. (2011). Tetrandrine, a Compound Common in Chinese Traditional Medicine, Preferentially Kills Breast Cancer Tumor Initiating Cells (TICs) In Vitro. Cancers, 3:2274-2285; doi:10.3390/cancers3022274.

Xu XH, Gan YC, Xu GB, et al. (2012). Tetrandrine citrate eliminates imatinib-resistant chronic myeloid leukemia cells in vitro and in vivo by inhibiting Bcr-Abl/ β-catenin axis. Journal of Zhejiang University SCIENCE B, 13(11):867-874.