Distribution of furamidine analogues in tumor cells: influence of the number of positive charges.
Fluorescence microscopy has been used to study the cellular distribution properties of a series of DNA binding cationic compounds related to the potent antiparasitic drug furamidine (DB75). The compounds tested bear a diphenylfuran or a phenylfuranbenzimidazole unfused aromatic core substituted with one or two amidine or imidazoline groups. The synthesis of five new compounds is reported. The B16 melanoma cell line was used to compare the capacities of mono-, bis-, and tetracations to enter the cell and nuclei. The high-resolution fluorescence pictures show that in the furamidine series, the compounds with two or four positive charges selectively accumulate in the cell nuclei whereas, in most cases, those bearing only one positive charge show reduced cell uptake capacities. One of the monocationic compounds, DB607, distributes in the cytoplasm, possibly in mitochondria, with no distinct nuclear accumulation. In sharp contrast, furamidine and benzimidazole analogues, including the drug DB293 that forms DNA minor groove dimers, efficiently accumulate in the cell nuclei and the intranuclear distribution of these DNA minor groove binders is significantly different from that seen with the DNA intercalating drug propidium iodide. The results suggest that the presence of two amidine terminal groups plays a role in facilitating nuclear accumulation into cells, probably as a result of nucleic acid binding. The determination of DNA melting temperature increases on addition of these compounds supports the importance of DNA binding in nuclear uptake.
Lansiaux
Amélie
A
INSERM U-524 et Laboratoire de Pharmacologie Antitumorale du Centre Oscar Lambret, IRCL, Place de Verdun, 59045 Lille, France.
Dassonneville
Laurent
L
Facompré
Michaël
M
Kumar
Arvind
A
Stephens
Chad E
CE
Bajic
Miroslav
M
Tanious
Farial
F
Wilson
W David
WD
Boykin
David W
DW
Bailly
Christian
C
D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics*; D000977:Antiparasitic Agents / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics*; D001550:Benzamidines / Q000737:chemistry / Q000378:metabolism / Q000493:pharmacokinetics*; D002412:Cations; D004247:DNA / Q000378:metabolism; D004560:Electricity; D008856:Microscopy, Fluorescence; D013329:Structure-Activity Relationship; D014018:Tissue Distribution; D014407:Tumor Cells, Cultured
D000970:Antineoplastic Agents; D000977:Antiparasitic Agents; D001550:Benzamidines; D002412:Cations; C033286:furamidine; D004247:DNA