Research on influence of TLR9 on pancreatic cancer nude mouse model growth and resistance to chemotherapy / 重庆医学

ABSTRACT

Objective To observe the effects of TLR9 on the nude mouse transplanted tumor growth of human pancreanc cancer and its drug resistance.Methods The nude mouse transplated tumor of human pancreatic cancer PANC-1 was established and randomly divided into 6 groups for conducting the experimentsterile normal saline group,TLR9 agonist,TLR9 inhibitor group,gemcitabine group,TLR9 inhibitor plus gemcitabine Bin group,TLR9 agonist plus gemcitabine.The tumor size and growth situation were recorded by the vernier caliper.The immunohistochemical method was used to detect tumor TLR9 receptor expression.The tumor growth,metastasis and paracancerous nssue invasion situation were observed by the magnetic resonance imaging (MRI).Results The volume and growth speed of resected tumor mass in the gemcitabine group,TLR9 agonist + gemcitabine group,TLR9 inhibitor plus gemcitabine group was significantly smaller than those in other groups (P＜0.05),which in the TLR9 agonist + gemcitabine group were significantly greater than those in the TLR9 inhibitor plus gemcitabine group and gemcitabine group (P＜0.05),the difference between the TLR9 inhibitor plus gemcitabine group and gemcitabine group had statistical significance (P＜0.05),while the difference among the TLR9 agonist group,TLR9 inhibitor group and normal saline group had no stastistical significance (P＞0.05).The tumor in mice at 7 weeks after planting showed oval shape with clear boundary by MRI observation,no obvious metastais and paracancerous invasion were seen in paracancerous nssues no statistically significant,5 weeks,6 weeks after planting,seven weeks mice observed in MRI,the tumor into an,state clearly that the transfer of the surrounding tissue,no significant vascular invasion,heart,liver,kidney disease.The TLR9 expression on the surface of tumor tissue was detected and identified.Conclusion Pancreatic cancer nude mouse transplated tumor has definitely positive expression of TLR9,TLR9 activation can significantly decrease the sensitivity of pancreatic cancer to chemotherapy,increases the drug resistance of tumor,on contrary promotes the tumor growth.