Avtor/Urednik		Čemažar, Maja; Auersperg, Marija; Serša, Gregor
Naslov		Vinblastine increases antitumor effectiveness of bleomycin
Prevedeni naslov		Viblastin poveča protitumorsko učinkovitost bleomicina
Tip		članek
Vir		Radiol Oncol
Vol. in št.		Letnik 31, št. 4
Leto izdaje		1997
Obseg		str. 364-7
Jezik		eng
Abstrakt		In our previous vinblastine (VELBE) was shown to increase the plasma membrane fluidity. This effect of VELBE might be expolited for better transport of drugs through the plasma membrane. Bleomycin (BLM) is a highly cytotoxic drug when present inside the cells but has a hampered transport through the plasma membrane. The aim of the present study was to determine whether pretreatment with VELBE can increase the effect of BLM on intraperitoneal SA-1 tumors in mice. BLM and VELBE were used as single agents or in various combinations, i.e. VELBE and BLM injected simultanously, BLM injected 24 h before VELBE or VELBE injected 24 h before BLM. Mice survival was the end-point used for determining the effect of this combined treatments. VELBE and BLM as a single treatment significantly prolonged median survival time of study animals compared to controls. Furthermore, when VELBE and BLM were combined, all three tested combinations were more effective than VELBE or BLM as single treatments. The effect on animal survival was equal when VELBE was given 24 h after or simultanously with BLM. The longest survival, however was obtained when VELBE was injected 24 h before BLM. From these results we can conclude that the underlying mechanisms for more than additive effect of VELBE and BLM when VELBE was given 24 h before BLM could be attributed to an increased membrane fluidity, possibly in combination with a cell kinetic effect.
Izvleček		V naši predhodni študiji smo ugotovili, da vinblastin poveča fluidnost plazemske membrane. S tem lahko povečamo vnos bleomcina, ki slabo prehaja preko plazemske membrane, a je zelo citotoksičen, če je prisoten v celici. Namen naše raziskave je bil na mišjih intraperitonealnih SA-1 tumorjih določiti, ali njiciranje vinblastina pred bleomicinom poveča učinkovitost bleomicina. Mišim smo injicirali samo vinblastin, samo bleomicin, vinblastin in bleomicin skupaj v različnih kombinacijah: vinblastin in bleomicin injicirana sočasno, bleomicin injiciran 24 h pred vinblastinom in vinblastin injiciran 24 h pred bleomicinom. Učinkovitost terapije smo ugotavljali s preživetjem živali. Zdravljenje z vinblastinom in bleomicinom je statistično značilno podaljšalo preživetje živali glede na kontrolno skupino. Vse tri kombinacije vinblastina in bleomicina so bile bolj učinkovite kot zdravljenje samo z enim kemoterapevtikom. Učinek terapije je bil enak, če smo sočasno injicirali vinblastin in bleomicin, ali če smo injicirali bleomicin 24 h pred vinblastinom. Najdaljše preživetje živali pa smo dobili, če smo injicirali vinblastin 24 h pred bleomicinom. Glede na naše rezultate lahko predpostavljamo, da sta za dobljeni učinek terapije odgovorna dva mehanizma delovanja vinblastina: povečanje fluidnosti membrane in vejretno celično kinetični efekt.
Deskriptorji		SARCOMA, EXPERIMENTAL VINBLASTINE BLEOMYCIN MICE ANTINEOPLASTIC AGENTS, COMBINED