Botulinum toxin type A inhibits the growth of LNCaP human prostate cancer cells in vitro and in vivo.
OBJECTIVE
Botulinum toxin type A (BTA) intraprostatic injection induces an improvement of urinary symptoms related to benign prostatic hypertrophy (BPH). Infra-clinical prostate cancer (PCa) foci and pre-neoplasic lesions occur concomitantly with BPH in a significant number of patients. The objective of this study was to address whether BTA influences the growth of prostate tumors.


METHODS
Proliferation of PC-3 and LNCaP cell lines exposed or not to BTA (Botox) was assessed and compared. Presence of synaptic vesicle 2 (SV2) protein, the membrane receptor of BTA, was studied in both cell lines. After nude mice bearing LNCaP xenografts received intra-tumoral BTA or saline injection, tumor volume, serum PSA, histopathology and detection of apoptosis were comparatively assessed.


RESULTS
BTA significantly reduced LNCaP cell proliferation and increased apoptosis in a dose-dependent manner but did not affect PC-3. The SV2 receptor was present in both cell lines at a ratio of 4:1 (LNCaP/PC-3). One unit of BTA resulted in a significantly lower growth rate and slower PSA progression over 28 days compare to controls. The tumors were morphologically similar. There were significantly more apoptotic cells compared to controls.


CONCLUSIONS
BTA inhibits the growth of LNCaP human PCa cells in vitro and in vivo. These findings indicate that intra-prostatic BTA injections to treat BPH are unlikely to promote the growth of co-existing infra-clinical PCa foci in men. A potential inhibitory effect of BTA on the growth of human PCa should be further studied.
Karsenty
Gilles
G
Department of Urology, Hôpital Sainte Marguerite, Assistance Publique-Hôpitaux de Marseille, Université de la Méditérranée, Marseille, France.
Rocha
Joice
J
Chevalier
Simone
S
Scarlata
Eleonora
E
Andrieu
Claudia
C
Zouanat
Fatima Z
FZ
Rocchi
Palma
P
Giusiano
Sophie
S
Elzayat
Ehab A
EA
Corcos
Jacques
J
D000230:Adenocarcinoma / Q000378:metabolism / Q000473:pathology*; D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D019274:Botulinum Toxins, Type A / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D006801:Humans; D008297:Male; D008562:Membrane Glycoproteins / Q000378:metabolism; D051379:Mice; D008819:Mice, Nude; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009498:Neurotoxins / Q000494:pharmacology*; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D014183:Transplantation, Heterologous
D008562:Membrane Glycoproteins; D009419:Nerve Tissue Proteins; D009498:Neurotoxins; C076414:SV2A protein, human; D019274:Botulinum Toxins, Type A