In vivo effect of high energy shock waves on growth and metastasis of the heterografted tumors of nude mice.
OBJECTIVE
To examine whether high energy shock waves (HESW) can inhibit tumor growth in vivo and whether it can promote the metastasis of the heterografted tumors of nude mice.


METHODS
Observations were made on the effect of HESW on tumor growth, histological and ultrastructural (transmission electron microscope, TEM) variations and metastasis to lymph nodes and viscera in the nude mice with heterografted tumors. The Dornier HM3 lithotripter was used under the working voltage of 15 kV, the impulse number being 0, 400 and 800 respectively, the temperature of waterbath, 35-37 degrees C and the impulse rate, 60/min.


RESULTS
HESW did have cytotoxic effect on tumors in vivo, including acute and chronic lethal effects and growth inhibitory effect, and it could act on levels of cell membrane, cytoplasmic organelles and nuclear chromatin. At a definite working voltage, this effect was positively proportional to the impulse number. The action mechanism of HESW in vivo might be direct mechanical damage and indirect inhibition of tumor growth as a result of causing damage to the blood supply. Histological examination showed no metastatic foci to the lymph nodes and viscera of the nude mice with the heterografted tumors.


CONCLUSIONS
HESW do inhibit tumor growth in vivo, but temporarily. This observation showed no tumor metastasis in the nude mice after the impulsion of HESW, but further studies on this topic are needed. It can be predicted that HESW will become a clinical method to treat the tumors after further investigation on its mechanism of action.
Zhou
L
L
First Clinical Medical College and Institute of Urology, Beijing Medical University.
Guo
Y
Y
D000818:Animals; D005260:Female; D006801:Humans; D008096:Lithotripsy / Q000009:adverse effects; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009362:Neoplasm Metastasis; D009368:Neoplasm Transplantation; D014407:Tumor Cells, Cultured; D001749:Urinary Bladder Neoplasms / Q000473:pathology* / Q000628:therapy*