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In search of selective carbonic anhydrase (CA) IX inhibitors endowed with apoptotic inducing properties, we designed and synthesised two subsets of 4- and 3-(5-aryl-(4-phenylsulphonyl)-1H-1,2,3-triazol-1-yl)benzene-sulphonamides. All compounds were assayed for human carbonic anhydrase (hCA) isoforms I, II, IV, and IX inhibition. Isoforms hCA I and hCA IV were weakly inhibited by most of the synthesised compounds. Many four-substituted benzenesulphonamides displayed low nanomolar inhibition against isoform hCA II, unlike the three-substituted analogues. All target compounds exhibited good inhibition profile with KI values ranging from 16.4 to 66.0 nM against tumour-associated isoform hCA IX. Some selective and potent inhibitors of hCA IX were assayed for in vitro apoptotic induction in goat testicular cells. Compounds 10d and 10h showed interesting apoptotic induction potential. The present study may provide insights into a strategy for the design of novel anticancer agents based on hCA inhibitors endowed with apoptotic interference. [ABSTRACT FROM AUTHOR]

Herbal polyphenols have gained increased significance because of the promises they hold in the prevention and treatment of cancer. There exists an enormous opportunity for the screening and valuation of natural dietary compounds in the development of an effective chemopreventive drug and radiosensitizer that may be of practical use for patients undergoing cancer therapy. This study describes the effect of the flavonoid ellagic acid (EA) on gamma-irradiated human breast cancer MCF-7 cellsin vitrowhen administered alone or in combination with radiation. It was interesting to find the radioprotective effect of EA on NIH3T3, which is a normal cell line. Irradiation of breast tumor cells in the presence of EA (10 μM) to doses of 2 and 4-Gy gamma radiation produced a marked synergistic tumor cytotoxicity while it was found to aid recovery from the radiation damage to NIH3T3 cells. When cells were given a combined treatment of EA and radiation, the cell death increased to 21.7% and 20.7% in the 2 and 4-Gy-treated cells respectively, significantly (P< 0.05) reducing the capacity of MCF-7 cells to form colonies. Even at 24 h, 38 foci/cell were observed in samples that were given the combined treatment, suggesting the cells' inability in repairing the damage. Also, increased apoptosis in EA+ 2Gy (50%) and EA+ 4 Gy (62%)-treated cells was observed in the the sub-G1 phase of the cell cycle. A 6.2-fold decrease in the mitochondrial membrane potential was observed in the combined treatment of EA and IR that facilitated the upregulation of pro-apopttotic Bax and downregulation of Bcl-2, pushing the MCF-7 cells to undergo an apoptotic cell death. It is suggested that EA may be a potential drug adjuvant for improving cancer radiotherapy by increasing tumor toxicity and reducing the normal cell damage caused by irradiation. [ABSTRACT FROM PUBLISHER]

Objective: Radio-resistance in tumor cells and associated escape from apoptotic mechanism is a major problem in clinical cancer radiotherapy. Therefore, as a strategy to enhance the apoptosis, a combination of radiation and tumor-selective cytotoxic agents might improve the efficacy of treatment. Thus, the radiomodifying potential of diospyrin diethylether (D7), a plant-derived antitumor agent, was studied in fibrosarcoma tumor, both in vitro and in vivo. Material and methods: Mouse and human fibrosarcoma (Wehi164; HT1080) cells were treated with D7, alone, or in combination with radiation, for determination of cytotoxicity, clonogenic survival, and apoptotic death assays. Involvement of oxidative mechanism and nuclear factor kappa B (NF-κB) was studied in different treatment groups. In addition, fibrosarcoma-bearing mice were treated with D7 (intravenously, two doses, each of 1 mg/kg body weight) combined with radiation (two fractions of 2.5 Gy each) at appropriate intervals. The tumor volume was measured to assess 'tumor growth delay', and liver function enzymes in the serum of mice were estimated after the treatments. Results: A combination treatment with D7 and radiation showed enhancement in cytotoxicity and apoptotic induction and decrease in clonogenic survival of tumor cells, as compared to the treatments with the drug or radiation alone. Moreover, D7 in combination with radiation could significantly inhibit the radiation-induced NF-κB activation, and showed the generation of comparatively more intracellular reactive oxygen species (ROS). Similarly, a combination of D7 and radiation in vivo caused significant inhibition of tumor growth in vivo, and restoring the liver enzyme activity to the 'normal' level. Conclusion: The combined treatment with quinonoid D7 and radiation caused increased cytotoxicity compared to single treatment with either agent alone in fibrosarcoma tumor systems, both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Co-therapy through biotin modified nanoparticles (NPs) of gefitinib (Gnb) and naringenin (Nar) was investigated for its therapeutic and synergistic potential against lung cancer. The biotin-conjugated polymeric NPs (bty-Nar/Gnb) were developed using oil in water emulsion technique and optimized using central composite design. The formulations were subjected to various in vitro (A549 cell lines) and in vivo evaluations in urethane-induced lung cancer. Co-administration of Gnb and Nar NPs displayed a significant reduction in tumour volume while restoring the biochemical parameters and serum metabolites to normal levels. Significant down-regulation of anti-apoptotic proteins (P-16, MMP-9 and Bcl-2) and up-regulation of pro-apoptotic proteins (caspase-9 and BAX) was displayed with co-therapy. This investigation demonstrated the superiority of co-therapy over individual therapy for improved therapeutic efficacy and is favourable for developing a safe, effective and targeted delivery for lung carcinoma therapy. [ABSTRACT FROM AUTHOR]