TLR4 expression in human gallbladder carcinoma cell Line SGC-996 and affects growth of xenograft tumor in nude mice

Abstract

Objective To observe the expression of TLR4 in human gallbladder cancer cell line SGC-996,and investigate whether RNA interference targeting TLR4 gene affect growth of the gallbladder carcinoma xenograft in nude mice. Methods The expression of TLR4 in SGC-996 was determined bv im-munohistochemistry and reverse transcription-polymerase chain reaction ( RT-PCR). 12 BALA/C nude mice were randomly divided into two groups. The experimental group was injected 6 x 10 SGC996 cells stable transfected by small interfering RNA for TLR4 per mice. The control group was injected with the same number of untreated SGC996 cells. Aftter continuous observation for 5 weeks, the formation rate, growth rate, weight and volume of the tumors were measured and calculated. Results The results of immunohistochem-istry and RT-PCR indicated the expression of TLR4 in SGC-996. The tumor formation rate of gallbladder carcinoma cell and TLR4-siRNA transfected SGC996 cell was 100%. The average tumor volume in experimental group and control group was (277.94±7.6 ) mm3 and (474.47±9.99) mm3 respectively. The growth rate was 7. 941% and 13. 556% ,and the average tumor weight was (0.76 ±0.16) g and (1.78± 0.23) g,respectively. The tumor growth rate,weight and volume in the experimental group decreased significantly when compared with those in control group (P<0.05). Conclusion Human gallbladder carcinoma cell line SGC-996 expresses TLR4. SGC-996 cells transfected with siRNA can effectively lower the level of TLR4 gene expression. After silence of TLR4 gene,the growth rate,weight and volume of xenograft are decreased significantly. Key words: TLR4; Gallbladder carcinoma; RNA interference; Nude mice