The Effect Of LIMK-1 Gene Silencing On Biological Behaviors Of The Ros Inhibit The Growth Of Human Gastric Carcinoma Of MGC803 Cells Subcutaneously Impanted Gastric Tumors

Objective: In our previous studies, we found that the over-expression of LIMK1 could promote the human gastric carcinoma of MGC803 cells growth, however, the human gastric carcinoma of MGC803 cells growth was inhibited after ROS treatment. In order to study the effect of LIMK-1 gene silencing on biological behaviors of ROS inhibit the growth of human gastric carcinoma of MGC803 cells subcutaneously impanted gastric tumors, we undertook the animal experiments.Methods: Human gastric cancer cells MGC803 in logarithmic growth phase were obtained by centrifugation and stored. Each BALB/C nude mice were inplanted subcutaneously in flanks with 200?l(1×107 cells per nude) MGC803 cells to produce the tumor. Once tumors reached a volume of 6~8mm,they were divided randomly into three groups: the LIMK1-sh RNA group, the NC-sh RNA group and the PBS group(n=16). Mice were received an intratumoral injection of 100?l(1×108TU/ml) of Lv-sh RNA-LIMK-1, Lv-sh RNA-NC, salined. After one week, they were randomized to six groups: the LIMK1-sh RNA plus ROS group(A group), the LIMK1-sh RNA plus NS group(B group), the NC-sh RNA plus ROS group(C group), the NC-sh RNA plus NS group(D group), the PBS plus ROS group(E group), the PBS plus NS group(F group). Rosiglitazone 100mg·Kg-1·2d-1, salined 200?l·2d-1.and detected the change of tumor volumes at different time. The mice were sacrificed after 28 days, and the subcutaneous tumor were measured. The morpholigical changes of tumor cells were observed by the optical microcope.The expression of LIMK-1 and Cofilin-1 in tumor was detected by immunohistochemistry,and the expression of LIMK-1 in tumor was detected by Western bolt.Results:1. The model of human gastric carcinoma of MGC803 subctaneous tumor in nude mice was successfully estabilished. The formation rate of subctaneous tumor in the A group 100%(8/8), B group 100%(8/8), C group100%(8/8), D group 62.5%(5/8), E group 75%(6/8), F group 62.5%(5/8).2. The tumor growth-curve showed that the tumor growth rate in the A was much slower than that in the C group and the E group(P<0.05). The tumor growth-curve showed that the tumor growth rate in the B group was much slower than that in the D group and the F group(P<0.05). The tumor growth-curve showed that the tumor growth rate in the E group was much slower than that in the F group(P<0.05), the same phenomenon was also observed in the C group and the D group.The tissues cut from the subctaneous tumor in nude mice have been diagnosed that was malignant tumor under microscop after HE stain.3. Immunohistochemistry results of the LIMK-1: Compared with the C group and the E group, there were few light brown granules in the A group(P<0.05),while there were some light brown granules in the C group and the E group(P>0.05). Compared with the D group and the F group, there were few brown granules in the B group(P<0.05),while there were lots brown granules in the D group and the F group(P>0.05).Compared with the E and the F group, there were lots brown granules in the F group(P>0.05), while they were some light brown in the E group(P<0.05), the same phenomenon was also observed in the C group and the D group.4.Western blot of the LIMK-1: Compared with the C group and the E group, there were lower expression of LIMK-1 in the A group(P<0.05),while the expression of LIMK-1 in the C group and the E group(P>0.05). Compared with the D group and the F group, there were lower expression of LIMK-1 in the B group(P<0.05),while the expression of LIMK-1 in the D group and the F group(P>0.05). Compared with the E and the F group, the expression of LIMK-1 of the former is lower the latter, the same phenomenon was also observed in the C group and the D group.5. Immunohistochemistry results of the Cofilin-1: There were a lot brown granules in the A group, C group and E group(P>0.05). The same phenomenon was also observed in the B group, D group and F group(P>0.05).Conclusions: 1. Rosiglitazone can slow the growth velocity of human gastric carcinoma of MGC803 subctaneous tumor of nude mice. 2. Intra-tumor injection of retrovirus Lv-sh RNA-LIMK-1 can slow the growth velocity of human gastric carcinoma of MGC803 subctaneous tumor of nude mice. 3. Lentivirus-meditated LIMK-1 gene silencing and rosiglitazone can synergistically inhibit the growth velocity of human gastric carcinoma of MGC803 subctaneous tumor of nude mice. 4. Rosiglitazone can inhibit the growth of human gastric carcinoma of MGC803 tumor in vivo possibly in downregulating the expression of LIMK-1.