Mechanism Of TTF1-NP Induced Implanted Hepatoma Tumor Apoptosis In Nude Mice By ERS Signal Pathway

Objective:To investigate the effect of 5,2’,4’-trihydroxy-6,7,5’-trimethoxy flavone nanoparticle (TTF1-NP) on inducing apoptosis of implanted tumour cells in nude mice and the mechanism of endoplasmic reticulum stress pathway.Methods:The implanted hepatoma model was established in nude mice, and then the nude mice were divided into five groups (vehicle,5 μmol·kg-1 TTF1-NP,10 μmol·kg-1 TTF1-NP,20 μmol·kg-1 TTF1-NP and adriamycin), treated with TTF1-NP separately. Then the nude mice were killed and the tumor growth inhibition ratio (IR) was calculated. Morphological changes of implanted tumor cells were observed by HE staining; Apoptosis of tumor cells was detected by TUNEL; the expression of GRP78, p-JNK and Caspase12 were analyzed by immunocytochemistry staining and western blot.Results:1. We tested the effects of TTF1-NP on implanted HepG-2 cell tumor growth in nude mice.The tumor volume of TTF1-NP-treated mice showed obviously smaller than that of the vehicle mice. The tumors of the TTF1-NP-treated mice were significantly lighter than those of the vehicle mice. In addition, the tumor growth ratio of the TTF1-NP-treated mice was significantly lower than that of the vehicle mice, and the tumor growth inhibition ratio of the TTF1-NP-treated mice was significantly higher than that of the vehicle mice. The results showed that inhibitory effect on implanted tumor cells after treatment with TTF1-NP was observed. The IR was 51.2%, 54.2%,61.8% and 65.9%, respectively.2. Morphological changes:In comparison with vehicle group, treated groups altered cell morphology and reduced cell number. Moreover, their nuclei became dark and pyknotic.3. TUNEL staining result:In vehicle group, their nuclei were stained blue and purple by hematoxylin. However, the tumor cells were positive expression obviously in TTF1-NP-treated group by TUNEL staining.4. Immunohistochemistry staining result:The expression of GRP78, p-JNK and Caspase12 were elevated and appeared positive expression area obviously in TTF1-NP-treated group.5. Western blot result:The expression of GRP78, p-JNK, Caspase12 and CHOP were increased with TTF1-NP dose by western blot.Conclusion:Taken together, our results show that TTFl-NP induce apoptosis of implanted tumor cells in nude mice and the main mechanism are related to endoplasmic reticulum stress pathway.