Effects of VM-26 and lonidamine on a B16 melanoma cell line.
The treatment of exponentially-growing B16 melanoma cells with teniposide causes a dose- and time-dependent decrease of cell survival. By means of the nucleoid technique, the formation of double strand breaks was demonstrated in the nuclei of the treated cells, indicating a possible involvement of topoisomerase II. DNA double strand breaks were rapidly but ineffectively repaired. Morphometric and densitometric analyses showed that teniposide treatment causes a considerable increase of nuclear area, nuclear DNA and cell size, associated with a lowering of the mitotic index to less than one hundredth of that of the controls. The cytocidal effect of VM-26 can be potentiated by the addition of a non-lethal dose of lonidamine, whose synergism is particularly evident at low teniposide concentrations.
Bellelli
A
A
Laboratory of Physiopathology, Regina Elena National Cancer Institute, Rome, Italy.
Bellelli
L
L
Di Palma
M
M
Lorenzon
I
I
Mattioni
M
M
Nista
A
A
Pavese
I
I
Rusconi
V
V
Sezzi
M L
ML
D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D002455:Cell Division / Q000187:drug effects; D002460:Cell Line; D002467:Cell Nucleus / Q000187:drug effects / Q000648:ultrastructure; D002470:Cell Survival / Q000187:drug effects; D002999:Clone Cells; D004347:Drug Interactions; D004354:Drug Screening Assays, Antitumor; D007191:Indazoles / Q000494:pharmacology*; D008546:Melanoma, Experimental; D051379:Mice; D008940:Mitotic Index / Q000187:drug effects; D011034:Podophyllotoxin / Q000031:analogs & derivatives*; D011720:Pyrazoles / Q000494:pharmacology*; D013713:Teniposide / Q000494:pharmacology*; D014407:Tumor Cells, Cultured / Q000166:cytology / Q000187:drug effects*
D000970:Antineoplastic Agents; D007191:Indazoles; D011720:Pyrazoles; D013713:Teniposide; D011034:Podophyllotoxin; C016371:lonidamine