anti-tumor immunity | Botanical Oncology

Cancer:
Lung, leukemia, cervical, breast, leukemia/lymphoma, choriocarcinoma

Action: Demethylation, anti-tumor immunity, induces apoptosis

Breast

The 27-kDa trichosanthin (TCS) is a ribosome inactivating protein purified from tubers of the Chinese herbal plant Trichosanthes kirilowii Maximowicz (tian hua fen). Fang et al. (2012) extended the potential medicinal applications of TCS from HIV, ferticide, hydatidiform moles, invasive moles, to breast cancer. They found that TCS manifested anti-proliferative and apoptosis-inducing activities in both estrogen-dependent human MCF-7 cells and estrogen-independent MDA-MB-231 cells.

Leukemia/Lymphoma, Cervical Cancer, Choriocarcinoma

Trichosanthin (TCS) as a midterm abortifacient medicine has been used clinically in traditional Chinese medicine for centuries. Additionally, TCS manifests a host of pharmacological properties, for instance, anti-HIV and anti-tumor activities. TCS has been reported to inhibit cell growth of a diversity of cancers, including cervical cancer, choriocarcinoma, and leukemia/lymphoma, etc. Sha et al. (2013) reviewed the various anti-tumor activities of TCS and the mechanism of apoptosis it induced in these tumor cells.

Lung, Anti-tumor Immunity

In this study, Cai et al. (2011) focused on the effect of TCS on murine anti-tumor immune response in the 3LL Lewis lung carcinoma tumor model and explored the possible molecular pathways involved. In addition to inhibiting cell proliferation and inducing apoptosis in the 3LL tumor, TCS retarded tumor growth and prolonged mouse survival more significantly in C57BL/6 immunocompetent mice than in nude mice. Data demonstrate that TCS not only affects tumor cells directly, but also enhances anti-tumor immunity via the interaction between TSLC1 and CRTAM.

Induce Apoptosis

Over the past 20 years, TCS has been the subject of much research because of its potential anti-tumor activities. Many reports have revealed that TCS is cytotoxic in a variety of tumor cell lines in vitro and in vivo. Monoclonal antibody-conjugated TCS could enhance its anti-tumor efficacy; thus, TCS is considered to be a potential biological agent for cancer treatment. TCS is able to inhibit protein synthesis and consequently induce necrosis. Recent studies have demonstrated that TCS does indeed induce apoptosis in several tumor cell lines (Li et al., 2010).

Leukemia

Cultured human leukemia K562 cells treated with trichosanthin were examined. Analysis of the cells by single laser flow cytometry showed the sub-G1 peak. DNA extracted from these cells formed a characteristic 'ladder' on agarose gel electrophoresis. Under electromicroscope, typical morphological changes of apoptosis were also observed. From all of these findings, Kang et al. (1998) concluded that trichosanthin was able to induce apoptosis in K562 cells.

Cervical Cancer, Demethylation Activity

Epigenetic silencing of tumor suppressor genes is a well-established oncogenic process and the reactivation of tumor suppressor genes that have been silenced by promoter methylation is an attractive molecular target for cancer therapy. In this study, Huang et al. (2012) investigated the demethylation activity of trichosanthin and its possible mechanism of action in cervical cancer cell lines. HeLa human cervical adenocarcinoma and CaSki human cervical squamous carcinoma cells were treated with various concentrations (0, 20, 40 and 80 µg/ml) of TCS for 48 hours and the mRNA and protein expression levels of the tumor suppressor genes adenomatous polyposis coli (APC) and tumor suppressor in lung cancer 1 (TSLC1) were detected using reverse transcription (RT)-PCR and Western blotting, respectively.

TCS induced demethylation in HeLa and CaSki cells and this demethylation activity was accompanied by the decreased expression of DNMT1 and reduced DNMT1 enzyme activity. Results demonstrate for the first time that TCS is capable of restoring the expression of methylation-silenced tumor suppressor genes and is potentially useful as a demethylation agent for the clinical treatment of human cervical cancer.

References:

Cai YC, Xiong SD, Zheng YJ, et al. (2011). Trichosanthin enhances anti-tumor immune response in a murine Lewis lung cancer model by boosting the interaction between TSLC1 and CRTAM. Cellular & Molecular Immunology, (2011)8:359–367. doi:10.1038/cmi.2011.12.

Fang EF, Zhang CZ, Zhang L, et al. (2012). Trichosanthin inhibits breast cancer cell proliferation in both cell lines and nude mice by promotion of apoptosis. PLoS One, 7(9):e41592. doi: 10.1371/journal.pone.0041592.

Huang Y, Song H, Hu H, et al. (2012). Trichosanthin inhibits DNA methyltransferase and restores methylation-silenced gene expression in human cervical cancer cells. Mol Med Rep, 6(4):872-8. doi: 10.3892/mmr.2012.994.

Kong M, Ke YB, Zhou MY, et al. (1998). Study on Trichosanthin induced apoptosis of leukemia K562 cells. Shi Yan Sheng Wu Xue Bao, 31(3):233-43.

Li M, Li X, Li JC. (2010). Possible mechanisms of trichosanthin-induced apoptosis of tumor cells. Anat Rec (Hoboken), 293(6):986-92. doi: 10.1002/ar.21142.

Sha O, Niu J, Ng TB, et al. (2013). Anti-tumor action of trichosanthin, a type 1 ribosome-inactivating protein, employed in traditional Chinese medicine: a mini review. Cancer Chemother Pharmacol, 71(6):1387-93. doi: 10.1007/s00280-013-2096-y.

Cancer: Breast, pancreatic, bladder, colorectal

Action: Damages DNA

Ukrain has been described as a semi-synthetic Chelidonium majus alkaloid derivative, consisting of three chelidonine alkaloids combined to triaziridide. Panzer et al. (2000) found the actions of Ukrain to be similar to the Chelidonium majus alkaloids from which it is prepared. Chelidonium majus contains a range of more than 30 alkaloids, most notably isochinolin derivatives (chelidonine, coptisine, berberin etc.). Chemical analyzes of Ukrain were inconsistent with the proposed trimeric structure and demonstrated that at least some commercial preparations of Ukrain consist of a mixture of C. majus alkaloids (including chelidonine) (Panzer et al., 2000).

Ukrain was developed in 1978 by Dr. Wassil J. Nowicky, director of the Ukrainian Anti-Cancer Institute of Vienna, Austria, and was first presented at the 13th International Congress of Chemotherapy in Vienna in August 1983. In 2004 and 2006, Nowicky was nominated for the Nobel Prize in Chemistry. The manufacturer of Ukrain is Nowicky Pharma, A-1040 Vienna, Austria.

Several reports describe Eastern European clinical trials using Ukrain for people with various types of cancer (Susak et al., 1996). The mechanism of action of Ukrain is unknown whereas the mechanism of action of thiotepa is known. The drug works by damaging the DNA of cells, leaving the cell unable to divide.

The proposed activity of Ukrain includes cytotoxicity from effects on cellular oxygen consumption, inhibition of DNA, RNA, and protein synthesis, and induction of apoptosis. In vitro studies demonstrate weak inhibition of tubulin polymerization causing arrest at G2/M phase of the cell-cycle. Limited in vitro data support the claim that Ukrain has selective cytotoxicity against cancer cells. Ukrain also is promoted for its claimed ability to increase total T-cell count and T-helper lymphocytes, while decreasing T-suppressor cells. In vitro activation of splenic lymphocytes also was reported (Colombo et al., 1996; Panzer et al., 2000; Uglyanitsa et al., 1998).

Ukrain has no drug approval in the EU. In the UK, Ukrain neither hasmarketing authorization nor is it registered under the “traditional use” label. It is not FDA-approved in the US but is approved in Mexico, and in the United Arab Emirates, as a standard anti-cancer medication. According to the manufacturer, NSC 631570 (=Ukrain) has drug licences in several states of the former Soviet Union (Ukraine, Georgia, Turkmenistan, Belarus/White Russia, Azerbaijan Republic, Tadshikistan, and the Ukraine. They also claim, without validation, that Ukrain has also been designated as an Orphan Drug for pancreatic cancer in the USA and in Australia (Human life Science Holding, n.d.).

There are seven RCTs assessing the efficacy of Ukrain for various cancer types (Ernst & Schmidt, 2005). The majority of these studies were published in two different journals between 1995 and 2002 by four different groups of authors, three from Belarus and one from Germany. They relate to colorectal (Susak et al., 1995; Susak et al., 1996) rectal (Bondar et al., 1998), bladder (Uglyanitsa et al., 1998), pancreatic (Zemskov et al., 2000; Zemskov et al., 2002), and breast cancers (Uglyanitsa et al., 2000). Ukrain exposure induced apoptosis in a dose- and time-dependent manner with 50 µg/mL Ukrain leading to >50% cell death after 48 hour exposure for all three breast cancer cell lines.

Ukrain administration (12.5 mg/kg) led to significant inhibition of 4T07 tumor growth in vivo and sustained protective anti-tumor immunity following secondary challenge. Findings demonstrate the in vitro and in vivo cytotoxic effects of Ukrain on breast cancer cells and may provide insight into designing Ukrain-based therapies for breast cancer patients (Bozeman et al., 2012).

While common anti-cancer drugs are toxic both against cancer and normal cells (cytostatics), Ukrain is allegedly only toxic against cancer cells (“malignocytolytic”). Some studies suggest that there was no evidence to suggest selective cytotoxicity previously reported for Ukrain (Panzer et al., 2000). Research carried out at the National Cancer Institute where Ukrain was tested on the screening panel with 60 cell lines from eight human cancer types, it was revealed to be cytotoxic against all the solid cancer cell lines tested (Boehm & Ernst, 2013).

References

Boehm, K., Ernst, E. (2013) CAM-Cancer Consortium. Ukrain [online document]. http://cam-cancer.org/CAM-Summaries/Herbal-products/Ukrain. August 21, 2013.

Bondar, G.V., Borota, A.V., Yakovets, Y.I., Zolotukhin, S.E.(1998) Comparative evaluation of the complex treatment of rectal cancer patients (chemotherapy and X-ray therapy, Ukrain monotherapy). Drugs Exp Clin Res 1998;24:221-6.

Bozeman, E.N., Srivatsan, S., Mohammadi, H., et al. (2012) Ukrain, a plant derived semi-synthetic compound, exerts anti-tumor effects against murine and human breast cancer and induce protective anti-tumor immunity in mice. Exp Oncol. 2012 Dec;34(4):340-7.

Colombo, M.L., Bosisio, E.. (1996) Pharmacological activities of Chelidonium majus L. (papaveracea). Pharmacol Res 1996;33:127-34.

Ernst, E., Schmidt, K. (2005) Ukrain – a new cancer cure? A systematic review of randomised clinical trials. BMC Cancer 2005;5:69-75.

Human life Science Holding. (n.d) http://www.open-cc.com/English/1_04.asp Accessed 2 December 2013

Panzer, A., Hamel, E., Joubert, A.M., Bianchi, P.C., Seegers, J.C.. (2000) Ukrain (TM), a semisynthetic Chelidonium majus alkaloid derivative, acts by inhibition of tubulin polymerization in normal and malignant cell lines. Cancer Lett 2000;160(2):149-57.

Susak, Y.M., Yaremchuk, O.Y., Zemskov, V.S., Kravchenko, O.B., et al. (1995) Randomised clinical study of Ukrain on colorectal cancer. Eur J Cancer 1995;31:S153 Abstract 733.

Susak, Y.M., Zemskov, V.S., Yaremchuk, O.Y., et al. (1996) Comparison of chemotherapy and x-ray therapy with Ukrain monotherapy for colorectal cancer. Drugs Exptl Clin Res 1996;22:115–22.

Uglyanitsa, K.N., Nechiporenko, N.A., Nefyodov, L.I., Brzosko, W.J. (1998) Ukrain therapy of stage T1NOMO bladder cancer patients. Drugs Exp Clin Res 1998;24:227-30.