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The effect of metal based complexes on the survival of aerobic and hypoxic chinese hamster ovary cells, in vitro.

Dissertation (MSc (Medical Physics))--University of Pretoria, 2007.

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Other Authors: Medlen, Connie E.
Format: Thesis
Published: University of Pretoria 2013
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access_status_str Open Access
author2 Medlen, Connie E.
author_browse Medlen, Connie E.
author_facet Medlen, Connie E.
collection Thesis
dc_rights_str_mv © 2001, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria.
description Dissertation (MSc (Medical Physics))--University of Pretoria, 2007.
format Thesis
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institution University of Pretoria (South Africa)
last_indexed 2026-06-10T12:36:48.396Z
license_str Other — see source repository
provenance_str_mv Harvested via OAI-PMH from UPSpace — University of Pretoria Institutional Repository
publishDate 2013
publishDateRange 2013
publishDateSort 2013
publisher University of Pretoria
publisherStr University of Pretoria
record_format dspace
source_str UPSpace — University of Pretoria Institutional Repository
spelling oai:repository.up.ac.za:2263/22781 The effect of metal based complexes on the survival of aerobic and hypoxic chinese hamster ovary cells, in vitro. Medlen, Connie E. upetd@up.ac.za Falzone, Nadia Radiotherapy Radiation-sensitizing agents Tumors Organometallic compounds Cisplatin UCTD Dissertation (MSc (Medical Physics))--University of Pretoria, 2007. It is well established that many solid tumours are heterogeneous with respect to oxygenation, and contain regions of hypoxic cells, which due to their inherent resistance to ionizing radiation, limit the success of radiotherapy. Numerous chemicals and drugs have been investigated over the past few decades as potential radiosensitizers. The most notable of these being the organometallic compound, cis-diammine dichloroplatinum(II). The clinical success of this drug led to the synthesis of other types of organic cytotoxic metal-containing drugs. Prof. J.C. Swart from the University of the Orange Free State supplied seventeen novel iridium, ferrecenium and rhodium complexes, which I screened for cytotoxic activity against the CHO cell line. The two most cytotoxic complexes namely, [Rh(fctca)(cod)] and [Rh(fctfa)(cod)], were tested for radiosensitizing potential against aerobic and hypoxic CHO cells in the presence of an 8 MV photon beam by the MTT assay adapted to our laboratory conditions. The ferrocene betadiketones co-ordinated to them, Hfctca and Hfctfa and the Ir compliment of [Rh(fctfa)(cod)] namely, [Ir(fctfa)(cod)] were also assessed by the MTT assay. Interestingly, neither the ferrocene nor the iridium complexes showed noteworthy sensitization, which suggests that the rhodium is responsible for the efficacy observed. The radiosensitizing potential of the most active complex, [Rh(fctfa)(cod)] and cisplatin were also confirmed by the use of the more traditional clonogenic assay. Not only did the MTT assay deliver results comparable to the clonogenic technique, but one of the complexes [Rh(fctfa)(cod)] showed radiosensitizing potential against hypoxic CHO cells, equal to that of cisplatin. The rhodium complex, [Rh(fctfa)(cod)] was also tested for radiosensitization properties against the CHO cell line in the presence of a p(66)/Be neutron beam. Results indicated that [Rh(fctfa)(cod)] sensitizes cells to radiation possibly by inhibition of cell inactivation mechanisms that are normally associated with repairable damage. Consequent work done on the flow cytometer where direct DNA damage after irradiation (8 MV photon beam) and drug treatment, was assessed on aerobic CHO cells by a technique adapted to our laboratory showed no significant increase in the forward angle scattered light (FSC) parameter which is an indication of radiation induced strand breaks. Furthermore, [Rh(fctfa)(cod)] showed a significantly greater increase in the side angle scattered light (SSC) parameter, which is an indication of the binding ability of the complex, compared to cisplatin, after treatment with different concentrations of the drugs. Results obtained from enumerating micronuclei frequencies after drug treatment and radiation confirmed that both cisplatin and [Rh(fctfa)(cod)] are more active under hypoxic conditions, with [Rh(fctfa)(cod)] responsible for more micronuclei per binucleated cell. In conclusion, I have established that [Rh(fctfa)(cod)] has a cytotoxic activity comparable to that of cisplatin and that it sensitizes preferentially hypoxic CHO cells to radiation in the clinically relevant dose range. I have also identified the probable action by which [Rh(fctfa)(cod)] sensitizes CHO cells to radiation as being inhibition of repair capacity. Furthermore, results suggest that this complex binds covalently to DNA base pairs. The complex [Rh (fctfa) (cod)] , has so far proven to possess interesting radiosensitizing potential which must be exploited for eventual therapeutic benefit. Medical Oncology unrestricted 2013-09-06T13:44:57Z 2006-03-03 2013-09-06T13:44:57Z 2001-04-21 2007-03-03 2006-02-24 Dissertation Falzone, N 2001 The effect of metal based complexes on the survival of aerobic and hypoxic Chinese hamster ovary cells, in vitro, MSc dissertation, University of Pretoria, Pretoria, viewed yymmdd < http://hdl.handle.net/2263/22781 > H216/ag http://hdl.handle.net/2263/22781 http://upetd.up.ac.za/thesis/available/etd-02242006-112303/ © 2001, University of Pretoria. All rights reserved. The copyright in this work vests in the University of Pretoria. No part of this work may be reproduced or transmitted in any form or by any means, without the prior written permission of the University of Pretoria. application/pdf University of Pretoria
spellingShingle Radiotherapy
Radiation-sensitizing agents
Tumors
Organometallic compounds
Cisplatin
UCTD
The effect of metal based complexes on the survival of aerobic and hypoxic chinese hamster ovary cells, in vitro.
title The effect of metal based complexes on the survival of aerobic and hypoxic chinese hamster ovary cells, in vitro.
title_full The effect of metal based complexes on the survival of aerobic and hypoxic chinese hamster ovary cells, in vitro.
title_fullStr The effect of metal based complexes on the survival of aerobic and hypoxic chinese hamster ovary cells, in vitro.
title_full_unstemmed The effect of metal based complexes on the survival of aerobic and hypoxic chinese hamster ovary cells, in vitro.
title_short The effect of metal based complexes on the survival of aerobic and hypoxic chinese hamster ovary cells, in vitro.
title_sort effect of metal based complexes on the survival of aerobic and hypoxic chinese hamster ovary cells in vitro
topic Radiotherapy
Radiation-sensitizing agents
Tumors
Organometallic compounds
Cisplatin
UCTD
url http://hdl.handle.net/2263/22781
http://upetd.up.ac.za/thesis/available/etd-02242006-112303/