Objective To investigate the inhibiting effect of
interleukin (IL)‐24 combined with targeted attenuated
Salmonella typhimurium vector SL7207/pBud‐VP3 on the
growth of
gastric cancer cells .
Methods The co‐expression eukaryotic expression
plasmid pBud‐VP3‐IL‐24 was constructed .The
plasmid pBud‐VP3‐IL‐24 was transformed into attenuated
Salmonella typhimurium SL7207 by using the high voltage
electroporation for constructing the SL 7207/pBud‐VP3‐IL‐24
strain .The
mouse gastric cancer transplantation tumor model was established and randomly divided into the
normal saline control group ,SL7207/pBud group , SL7207/pBud‐VP3 group and SL7207/pBud‐VP3‐IL‐24 group .The
tumor‐bearing
mice were fed by
oral administration of bacterial
strain .The
tumor volume was measured and the
tumor inhibition rate was calculated .The expression of IL‐24 was detected by
Western blotting .The levels of IFN‐γ,IL‐6 and TNF‐αin
tumor tissue were detected by using RT‐
PCR .The expression of
Caspase‐3 and
VEGF were detected by using
immunohistochemistry .Results The
plasmids attenuated
Salmonella typhimurium vector
carrying the
gene IL‐24 was successfully constructed .The IL‐24
protein expression was detected in
gastric cancer tissue after 14 d
treatment .The
tumor volume after 28 d
treatment in the SL7207/pBud‐VP3‐IL‐24 group was reduced compared with the other groups ,moreover the
tumor growth was significantly inhibited ,and the differences were statistically significant (P<0 .05) .RT‐
PCR and
immunohistochemistry results showed that IL‐24 combined with SL7207/bBud‐VP3 could significantly increase the expression levels of
immune factor IL‐6 ,IFN‐γ and TNF‐αin
tumor tissue ,.in addition ,up‐regulated the expression of
Caspase‐3 and down‐regulated the
VEGF expression(P<0 .05) .Conclu‐sion IL‐24 combined with SL7207/pBud‐VP3 can synergically
play the inhibitory effect on the
growth of
gastric cancer cells ,its mecha‐nism is related with the
tumor apoptosis promotion ,
tumor vessel inhibition and immune
regulation .