Electrically mediated drug delivery for treatment of an adenocarcinoma transplanted into rat liver.
BACKGROUND
In this study, electrochemotherapy (ECT), i.e. tumour treatment based on local augmentation of intracellular drug delivery from short, intense electric pulses, was evaluated in rats with an adenocarcinoma implanted into the liver. Tumour response and concentrations of macrophages and T-lymphocytes (CD4 and CD8) in and around the tumour were measured.


METHODS
Rats were treated with permeabilizing electric pulses, bleomycin, or both, eight days after implantation of the tumour, while one group received sham treatment.


RESULTS
Treatment with electric pulses and bleomycin resulted in a significantly reduced lesion volume and 92% cure rate (12 out of 13, p<0.0002 compared to the other treatment groups). The highest concentration of CD8 lymphocytes was found in tumours treated with electric pulses and bleomycin. Macrophages were found mainly in tumours treated with electric pulses, with or without bleomycin.


CONCLUSIONS
Electrochemotherapy using millisecond exponential pulses and bleomycin is efficient in a rat liver tumour model and appears to stimulate the host's immune system.
Engström
P E
PE
Department of Radiation Physics, Lund University Hospital, Sweden.
Ivarsson
K
K
Tranberg
K G
KG
Stenram
U
U
Salford
L G
LG
Persson
B R
BR
D000230:Adenocarcinoma / Q000188:drug therapy*; D000410:Alanine Transaminase / Q000097:blood; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D001761:Bleomycin / Q000494:pharmacology; D015496:CD4-Positive T-Lymphocytes / Q000378:metabolism; D018414:CD8-Positive T-Lymphocytes / Q000378:metabolism; D003131:Combined Modality Therapy; D016503:Drug Delivery Systems; D004599:Electric Stimulation Therapy / Q000379:methods*; D018274:Electroporation / Q000379:methods; D007150:Immunohistochemistry; D008099:Liver / Q000473:pathology*; D008264:Macrophages / Q000378:metabolism; D008297:Male; D009368:Neoplasm Transplantation; D051381:Rats; D017208:Rats, Wistar
D000964:Antimetabolites, Antineoplastic; D001761:Bleomycin; D000410:Alanine Transaminase