Photofrin-mediated Photodynamic Therapy Cross-Resistance to Cisplatin in Cells Resistant to
نویسندگان
چکیده
mechanisms of cisplatin resistance, since resistance greater than about 5-fold may not be clinically relevant (3). In this paper, we present a novel model system to study cisplatin resistance in vitro, utilizing cells resistant to PDT and which demon strate cisplatin cross-resistance. Previously, we characterized RIF-1 and its PDT-resistant variant (RIF-8A) and demonstrated morpholog ical and functional mitochondrial differences (4). The structural changes in the mitochondria of RIF-8A cells strongly resemble those observed in C135 cells (5), a cisplatin-induced resistant variant of the human ovarian carcinoma cell line (2008), in that the mitochondria in the resistant variants appeared to be in a condensed state with densely staining cristae compared to their respective parental line. The mito chondrial changes in C13* cells contributed to cisplatin resistance through an undetermined mechanism (5, 6). Therefore, RIF-8A cells were further investigated to determine if the mitochondrial structural alterations provided similar functional changes as observed in C13* cells (5) and if the mitochondrial alterations contributed to the cispla tin cross-resistance.
منابع مشابه
Cross-resistance to cisplatin in cells resistant to photofrin-mediated photodynamic therapy.
This study shows that a Photofrin-induced photodynamic therapy-resistant variant (RIF-8A) of a radiation-induced fibrosarcoma-1 cell line (RIF-1) is cross-resistant to cis-diamminedichloroplatinum(II) (cisplatin). This is the first study to show cross-resistance to cisplatin in photodynamic therapy-resistant variants in vitro. Resistance does not appear to be the result of elevated glutathione ...
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