The Research On Mechanism Of Lymphangiogenesis In Xenogenic Human Colonic Cancer In Nude Mice

Objective To establish model of xenogenic human colonic cancer in nude mice and explore the mechanism and characteristic of lymphangiogenesis during the growth process of the tumor.Methods A planted tumor model bearing in BALB/c nude mice was established using human colonic cancer HCT-116cells. In pre-experiment, execute the nude mouse according to different time points and detect the change of lymphatic vessel desenty in the case of natrural growth state by dyeing the paraffin section using immunohistochemistry, and define the day10of planted tumor growthing as early interventional time point. Then established the planted tumor bearing in nude mice model of human colonic cancer and divided them into three groups randomly(natrual growth group; interventional contral group:DMSO;interventional group:the inhibitor WP1066for STAT3dissolving in DMSO). The day23of planted tumor growthing, the mRNA transcription level of STAT3、VEGF-C. podoplanin was determined by real-time quantitive PCR using fluorescence and the protein expression of STAT3、 VEGF-C、podoplanin was tested by immunohistochemistry staining, then analysed the change of above-mentioned indexes by comparing to the early experimental data that their interventional time point were fourteenth.Results In natrural growth state of pre-experiment, the lymphatic vessel desenty in planted tumor is high in day21of planted tumor growthing. the lymphatic vessel desenty is low in days from7to13and from31to41of planted tumor growthing.In natrural growth group, the mRNA transcription level and protein expression of STAT3in tumor tissues have no significant difference between the day23and27of planted tumor growthing (p>0.05). The mRNA transcription level and protein expression of STAT3in tumor tissues have no significant difference between the day23and27of planted tumor growthing (p>0.05). The protein expression of podoplanin in tumor tissues have no significant difference between the day23and27of planted tumor growthing (p>0.05).The mRNA transcription level of STAT3were significantly lower in early intervention over than late intervention over(p<0.05), but the protein expression of STAT3in tumor tissues have no significant difference between early intervention over and late intervention over(p>0.05).The mRNA transcription level of VEGF-C were significantly lower in early intervention over than late intervention over(p<0.05), but the protein expression of VEGF-C in tumor tissues have no significant difference between early intervention over and late intervention over(p>0.05). The protein expression of podoplanin were significantly lower in early intervention over than late intervention over(p<0.05).In early intervention over, the tumor size and the mRNA transcription level and protein expression of STAT3、VEGF-C、podoplanin have no significant difference between natrural growth group and interventional control group (p>0.05). However, the tumor size of interventional group is significantly smaller than other two groups(p<0.05); The mRNA transcripton level and protein expression of STAT3、 VEGF-C and podoplanin of interventional group are significantly lower than other two groups (p<0.05).Positive correlation among STAT3、VEGF-C and podoplanin were detected in mRNA transcription level and protein expression in planted tumor.Conclusion In natrural growth state, the changes of lymphatic vessel desenty of planted tumor bearing in nude mouse model of human colonic cancer display the normal distribution, show increasing gradually and then decreasing gradually along with the growth of the planted tumor.The inhibitor WP1066for STAT3can inhibit the growth of tumor, and inhibit the lymphangiogenesis by decreasing the expression of STAT3and VEGF-C.Using the inhibitor WP1066for STAT3early can significantly inhibit the lymphangiogenesis of planted tumor, it indicate that the treatment effect of early intervention to tumor is evident, and lymphatic vessel may be more important in early stage of tumor.