The allylic 7-ketone at the steroidal skeleton is crucial for the antileukemic potency of chlorambucil's active metabolite steroidal esters.
We have investigated the role of the allylic 7-ketone in oxidized Delta5-steroids on antileukemic activity. We synthesized and studied a series of oxidized and non-oxidized steroidal esters of p-N,N-bis(2-chloroethyl)aminophenylacetic acid (PHE), chlorambucil's active metabolite. In a comparative study of these 7-keto derivatives, on a molecular basis, regarding their ability to induce sister chromatid exchanges (SCEs) and to inhibit cell proliferation in normal human lymphocytes in vitro, the results with these 7-keto derivatives, on a molecular basis, correlated well with their antileukemic potency against leukemia P388- and L1210-bearing mice, which proved to be significantly increased compared to that of the non-oxidized derivatives. Our results indicate that the role of the steroidal skeleton it is not only for the transportation of the alkylating agent into the cell, but also contributes directly to the mechanism of antileukemic action, by an as-yet unknown way. The main conclusion from this study is that the existence of the allylic 7-keto group in the skeleton of the Delta5-steroidal esters impressively enhances their antileukemic activity, while the toxicity remains at clinically acceptable levels, suggesting that this structural modification should be further investigated.
Arsenou
Evaggelia S
ES
Laboratory of Pharmaceutical Chemistry, School of Health Sciences, Department of Pharmacy, University of Patras, Rion-Patras, Greece.
Fousteris
Manolis A
MA
Koutsourea
Anna I
AI
Papageorgiou
Athanasios
A
Karayianni
Venetia
V
Mioglou
Eleftheria
E
Iakovidou
Zafiria
Z
Mourelatos
Dionysios
D
Nikolaropoulos
Sotiris S
SS
D000736:Androstenes / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000737:chemistry* / Q000494:pharmacology*; D049109:Cell Proliferation / Q000187:drug effects; D004952:Esters / Q000138:chemical synthesis / Q000737:chemistry / Q000494:pharmacology; D005260:Female; D007659:Ketones / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D007928:Lethal Dose 50; D007939:Leukemia L1210 / Q000188:drug therapy; D007941:Leukemia P388 / Q000188:drug therapy; D008214:Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000648:ultrastructure; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008811:Mice, Inbred DBA; D010648:Phenylacetates / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D012854:Sister Chromatid Exchange; D013329:Structure-Activity Relationship
D000736:Androstenes; D018906:Antineoplastic Agents, Alkylating; D004952:Esters; D007659:Ketones; D010648:Phenylacetates