Anticancer research
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Anticancer research · Jan 2007
Cytotoxic activity and absence of tumor growth stimulation of standardized mistletoe extracts in human tumor models in vitro.
Mistletoe extracts are widely used in complementary and alternative cancer therapy in Europe. The extracts possess cytotoxic, as well as immunostimulatory effects. However, some investigators have suggested that low doses of mistletoe extracts could also induce tumor growth. ⋯ Further investigations into the latter effect of Helixor M and ML-1 in the HCC-2998 line using five different proliferation assays, modified cell culture conditions and the identical production charge of mistletoe extract, as well as a new one, did not confirm the previous observation. It was concluded that the marginal stimulation found in the earlier experiments was a statistical coincidence. Helixor mistletoe preparations and ML-1 have cytotoxic activity and do not stimulate tumor cell proliferation in vitro which is in accordance with previous scientifically based observations on aqueous mistletoe extracts.
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Anticancer research · Jan 2007
Imatinib mesylate inhibits tumorigenicity of malignant fibrous histiocytoma cells in vivo.
Malignant fibrous histiocytoma (MFH) is one of the most diffuse and aggressive tumors among soft tissue sarcomas in adults, but still poorly characterized from the molecular viewpoint. MFH cell proliferation is inhibited selectively by imatinib mesylate, a tyrosine kinase inhibitor. The expressions of platelet-derived growth factor receptors (PDGFRs) and c-Kit have been previously examined in MFH cell lines and the inhibitory effect of imatinib mesylate on the MFH cell proliferation was tested. MFH cell lines showed various patterns of PDGFRs and c-Kit expression. Imatinib mesylate inhibited the proliferation of MFH cells that expressed PDGFRs and/or c-Kit. ⋯ Imatinib mesylate reduced in vivo tumor growth of MFH that express PDGFRs and c-Kit associated with phosphorylation suppression.
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Anticancer research · Nov 2006
Intratumoral application of standardized mistletoe extracts down regulates tumor weight via decreased cell proliferation, increased apoptosis and necrosis in a murine model.
The cytotoxic in vitro activity of standardized mistletoe extracts (ME) was examined by established assays towards the human ductal breast carcinoma cell line BT474. A dose-dependent (optimum 25 mg/mL medium) and significantly (p < 0.05) enhanced cytotoxic activity towards the BT474 cells was demonstrated. In vivo experiments on the antitumor activity of ME-A and ME-M were performed in a BALB/c-mouse / BT474 ductal breast carcinoma model. ⋯ Histological investigations were performed comprising analysis of mitosis and proliferation rates (Ki67 expression), as well as necrosis and apoptosis induction (ssDNA detection). As compared to tumors of control mice with intratumoral phosphate-buffered saline (PBS) injections, tumors of the ME-A and ME-M treated groups showed a decreased cell proliferation rate, as well as an increased cell necrosis and apoptosis rate. Standardized mistletoe extracts, interfering with defined tumor cell functions, e.g., proliferation, necrosis and apoptosis, may have an impact on local cancer treatment.
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Surgery remains the only curative therapy for colon cancer. However, several studies during the last years have proved that systemic chemotherapy in the adjuvant setting definitely improves the curative rate for those patients with localized colon cancer. ⋯ The role of adjuvant therapy in stage II cancers remains controversial and its routine use is recommended only in high risk patients. This review focuses on the efficacy, safety and toxicity of several drugs used in the adjuvant treatment of colon cancer and on clinical issues, such as the timing for initiation of chemotherapy, its duration and treatment of special patient subgroups, such as stage II or elderly patients.
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Anticancer research · Nov 2006
COX-2 inhibitor celecoxib suppresses tumor growth and lung metastasis of a murine mammary cancer.
The antitumor growth and antimetastatic actions of celecoxib [a selective cyclooxygenase-2 (COX-2) inhibitor] were investigated in a metastatic murine mammary cancer model. ⋯ Celecoxib may be useful as an adjuvant therapy for breast cancer containing p53 mutations due to its ability to both induce p53-independent mitochondria-mediated apoptosis and exert anti-angiogenic potential.