Prolongation of pentoxifylline aliphatic side chain positively affects the reversal of P-glycoprotein-mediated multidrug resistance in L1210/VCR line cells.
We reported previously that derivatives of pentoxifylline (PTX) reverse multidrug resistance (MDR) in P-glycoprotein (P-gp) positive L1210/VCR cells. Based on the results of a recent study using 25 N-alkylated methylxanthines with carbohydrate side-chains of various lengths, we formulated the following design criteria for a methylxanthine molecule to effectively reverse P-gp mediated MDR: i) a massive substituent at the N1 position is crucial for MDR reversal potency; ii) elongation of the substituents at the N3 and N7 positions (from methyl to propyl) increases the efficacy of a xanthine to reverse MDR; iii) elongation of the substituent at the C8 position (from H to propyl) decreases the efficacy of a xanthine to reverse MDR. Based on these criteria, we synthesized and tested for potency to reverse MDR a new PTX derivative, 1-(10-undecylenyl)-3-heptyl-7-methyl xanthine (PTX-UHM), with prolonged substituents at the N1 and N3 positions. The derivative was obtained by alkylation of 3-heptyl-7-methyl xanthine with 1-methylsulfonyloxy-10-undecylenyl. NMR and IR structural analyses proved the identity of the product. Cytotoxicity study showed that PTX-UHM is only slightly more toxic to L1210/VCR cells than PTX. We found that both PTX-UHM and PTX were able to reverse vincristine resistance of L1210/VCR cells, yet PTX-UHM was significantly more efficient in the reversal than PTX.
Institute of Molecular Physiology and Genetics, Slovak Academy of Sciences, Vlárska 5, 833 34 Bratislava 37, Slovakia. peter.docolomansky@savba.sk
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Docolomanský
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Fialová
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Barancík
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Rybár
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Breier
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1 / Q000378:metabolism*; D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D002460:Cell Line; D045744:Cell Line, Tumor; D002470:Cell Survival / Q000187:drug effects; D004305:Dose-Response Relationship, Drug; D018432:Drug Resistance, Multiple / Q000187:drug effects*; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D007939:Leukemia L1210 / Q000378:metabolism* / Q000473:pathology*; D051379:Mice; D010431:Pentoxifylline / Q000008:administration & dosage* / Q000031:analogs & derivatives* / Q000737:chemistry; D013329:Structure-Activity Relationship; D014750:Vincristine / Q000008:administration & dosage; D019820:Xanthine / Q000008:administration & dosage
D020168:ATP Binding Cassette Transporter, Subfamily B, Member 1; D000970:Antineoplastic Agents; D019820:Xanthine; D014750:Vincristine; D010431:Pentoxifylline