| 1. |
- Burman, Robert, 1979-, et al.
(författare)
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Evaluation of toxicity and anti-tumour activity of cycloviolacin O2 in mice.
- 2010
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Ingår i: Biopolymers. - : Wiley. - 0006-3525 .- 1097-0282. ; 94:5, s. 626-634
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Tidskriftsartikel (refereegranskat)abstract
- Cycloviolacin O2 is a small cyclic cysteine-rich protein belonging to the group of plant proteins called cyclotides. This cyclotide has been previously shown to exert cytotoxic activity against a variety of human tumor cell lines as well as primary cultures of human tumor cells in vitro. This study is the first evaluation of its tolerability and antitumor activity in vivo. Maximal-tolerated doses were estimated to 1.5 mg/kg for single intravenous (i.v.) dosing and 0.5 mg/kg for daily repeated dosing, respectively. Two different in vivo methods were used: the hollow fiber method with single dosing (i.v. 1.0 mg/kg) and traditional xenografts with repeated dosing over 2 weeks (i.v. 0.5 mg/kg daily, 5 days a week). The human tumor cell lines used displayed dose-dependent in vitro sensitivity (including growth in hollow fibers to confirm passage of cycloviolacin O2 through the polyvinylidene fluoride fibers), with IC50 values in the micromolar range. Despite this sensitivity in vitro, no significant antitumor effects were detected in vivo, neither with single dosing in the hollow fiber method nor with repeated dosing in xenografts. In summary, the results indicate that antitumor effects are minor or absent at tolerable (sublethal) doses, and cycloviolacin O2 has a very abrupt in vivo toxicity profile, with lethality after single injection at 2 mg/kg, but no signs of discomfort to the animals at 1.5 mg/kg. Repeated dosing of 1 mg/kg gave a local-inflammatory reaction at the site of injection after 2–3 days; lower doses were without complications.
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| 2. |
- Fryknäs, Mårten, et al.
(författare)
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Screening for phenotype selective activity in multidrug resistant cells identifies a novel tubulin active agent insensitive to common forms of cancer drug resistance
- 2013
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Ingår i: BMC Cancer. - : Springer Science and Business Media LLC. - 1471-2407. ; 13, s. 374-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Drug resistance is a common cause of treatment failure in cancer patients and encompasses a multitude of different mechanisms. The aim of the present study was to identify drugs effective on multidrug resistant cells. Methods: The RPMI 8226 myeloma cell line and its multidrug resistant subline 8226/Dox40 was screened for cytotoxicity in response to 3,000 chemically diverse compounds using a fluorometric cytotoxicity assay (FMCA). Follow-up profiling was subsequently performed using various cellular and biochemical assays. Results: One compound, designated VLX40, demonstrated a higher activity against 8226/Dox40 cells compared to its parental counterpart. VLX40 induced delayed cell death with apoptotic features. Mechanistic exploration was performed using gene expression analysis of drug exposed tumor cells to generate a drug-specific signature. Strong connections to tubulin inhibitors and microtubule cytoskeleton were retrieved. The mechanistic hypothesis of VLX40 acting as a tubulin inhibitor was confirmed by direct measurements of interaction with tubulin polymerization using a biochemical assay and supported by demonstration of G2/M cell cycle arrest. When tested against a broad panel of primary cultures of patient tumor cells (PCPTC) representing different forms of leukemia and solid tumors, VLX40 displayed high activity against both myeloid and lymphoid leukemias in contrast to the reference compound vincristine to which myeloid blast cells are often insensitive. Significant in vivo activity was confirmed in myeloid U-937 cells implanted subcutaneously in mice using the hollow fiber model. Conclusions: The results indicate that VLX40 may be a useful prototype for development of novel tubulin active agents that are insensitive to common mechanisms of cancer drug resistance.
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| 3. |
- Hassan, Saadia Bashir, et al.
(författare)
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Alpha Terpineol : A Potential Anticancer Agent which Acts through Suppressing NF-kappa B Signalling
- 2010
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Ingår i: Anticancer Research. - 0250-7005 .- 1791-7530. ; 30:6, s. 1911-1919
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Tidskriftsartikel (refereegranskat)abstract
- Background: Alpha terpineol is a bioactive component of Salvia libanotica essential oil extract and has shown antitumour activity. Materials and Methods: The cytotoxicity of alpha terpineol towards different tumour cell lines was evaluated in vitro. Mechanistic characterization was performed using analysis of drug activity in a cell line panel and drug-induced gene expression perturbation using the connectivity map approach. Results: The small cell lung carcinoma was the cell line most sensitive to alpha terpineol. The results proposed alpha terpineol as an NF-kappa B inhibitor, which was confirmed by the observed dose-dependent inhibition of NF-kappa B translocation and activity using two NF-kappa B assays, and by the down-regulation of the expression of several NE-kappa B-related genes such as IL-1 beta and IL1R1. Conclusion: The results suggest that alpha terpineol inhibits the growth of tumour cells through a mechanism that involves inhibition of the NF-kappa B pathway.
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| 4. |
- Hassan, Saadia Bashir, et al.
(författare)
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The Nanoparticulate Quillaja Saponin BBE Is Selectively Active Towards Renal Cell Carcinoma
- 2013
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Ingår i: Anticancer Research. - 0250-7005 .- 1791-7530. ; 33:1, s. 143-151
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Tidskriftsartikel (refereegranskat)abstract
- Aim: To characterize the cytotoxic effect of BBE, the particulate of desacyl-saponin, in model systems of solid tumours. Materials and Methods: Cytotoxic activity of BBE was investigated in solid human tumour cell lines, in tumour cells from patients with renal cell carcinoma, in normal human renal cells and in peripheral blood mononuclear cells. The BBE mode of cell death was assessed in vitro. In vivo effect of BBE was evaluated in xenograft-bearing mice. Results: BBE was selectively active against renal cell carcinoma, with no or little effect on normal cells. BBE induced caspase activity and apoptosis. An inhibitory activity of BBE on xenograft tumour growth, with no apparent signs of haematological toxicity was shown. In the non-proliferative model of patient tumour cells, BBE was active on only 1/5 patient samples, suggesting association of BBE effect with cell proliferation. Conclusion: BBE has interesting activities against renal cell carcinoma and should be further explored as a drug against this resistant tumour type.
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| 5. |
- Hassan, Saadia, et al.
(författare)
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Novel activity of acriflavine against colorectal cancer tumor cells
- 2011
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Ingår i: Cancer Science. - : Wiley. - 1347-9032 .- 1349-7006. ; 102:12, s. 2206-2213
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Tidskriftsartikel (refereegranskat)abstract
- A high-throughput screen of the cytotoxic activity of 2000 molecules from a commercial library in three human colon cancer cell lines and two normal cell types identified the acridine acriflavin to be a colorectal cancer (CRC) active drug. Acriflavine was active in cell spheroids, indicating good drug penetration and activity against hypoxic cells. In a validation step based on primary cultures of patient tumor cells, acriflavine was found to be more active against CRC than ovarian cancer and chronic lymphocytic leukemia. This contrasted to the activity pattern of the CRC active standard drugs 5-fluorouracil, irinotecan and oxaliplatin. Mechanistic studies indicated acriflavine to be a dual topoisomerase I and II inhibitor. In conclusion, the strategy used seems promising for identification of new diagnosis-specific cancer drugs.
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| 6. |
- Larsson, Dhana E., et al.
(författare)
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The Cytotoxic Effect of Emetine and CGP-74514A Studied with the Hollow Fiber Model and ArrayScan Assay in Neuroendocrine Tumors In Vitro
- 2012
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Ingår i: ANTI-CANCER AGENT ME. - 1871-5206. ; 12:7, s. 783-790
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Tidskriftsartikel (refereegranskat)abstract
- Emetine and CGP-74514A have previously shown antitumor activity in neuroendocrine tumor cell lines. The aim of this study was to investigate the cytotoxic activity of the drugs in a three-dimensional model and to study if the mechanism of the cytotoxic activity was induction of apoptosis. An in vitro hollow fiber model was used to study the cytotoxic effect and a multiparametric high-content screening assay was used for measurement of apoptosis. The human pancreatic carcinoid cell line, BON-1 and the human typical and atypical bronchial carcinoid cell lines NCI-H727 and NCI-H720 were tested. Emetine and CGP-74514A showed higher antitumor activity on NCI-H720 compared to NCI-H727 and 3 day cultures were more sensitive than the 14 day cultures. A time-and dose-dependent activation of caspase-3 and increase in nuclear fragmentation and condensation were observed for the drugs in NCI-H727 and BON-1 using a multiparametric apoptosis assay. These results were confirmed with nuclear morphological examinations on microscopic slides. Emetine and CGP-74514A showed antitumor activity and induced caspase-3 activation with modest changes in nuclear morphology, indicating induction of apoptosis.
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