The Correlation Analysis Between Endothelin-1Gene Polymorphisms And Risk Of Chemoresistant Of Child And Adolescent Osteosarcoma

Objective:we for the first time explored the association of ET-1SNPs and haplotypes with the risk of chemoresistant OS in a case-control study, and provided the first evidence of an association between the ET-1gene SNPs and haplotypes and the risk of chemoresistant pediatric OS, thereby adding fresh insights into the pathophysiology and treatment of chemoresistant pediatric OS.Method:This study is divided into three parts,First,we use350pairs of age, sex, and tumor location and stage matched pediatric OS patients. Second,genomic DNA was isolated from white blood cells using the phenol/chloroform method and was stored in400ml of TE(10mM Tris/HCl and1mM EDTA (pH8.0).SNPs of ET-1were genotyped using ABI3700DNA Analyzers (Applied Biosystems).Using Hardy-Weinberg equilibrium test to results,and using matching LD experiment to rs1800541and rs2070699, calculated by HaploView program.At last, all the results for statistical analysis;Third,we processd POCC through the specimens of osteosarcoma, and continued to subculture for POCC,We proceed real-time quantitative reverse transcription polymerase chain reaction(RT-PCR) using POCC obtained above to detected ET-1mRNA levels, and detected the cell-secreted ET-1levels in POCC supernatants through the enzyme-linked immunosorbent assay (ELISA),and watch the percentage of tumor necrosis.Result:1.There was no significant difference in age,sex, and distribution of tumor location and stage.There was also no significant difference in body mass index, systolic blood pressure, diastolic blood pressure, and plasma ET-1levels between cases and controls.2.Among the three SNPs, rs5370was found to deviate significantly from Hardy-Weinberg equilibrium in controls.3.The Gallele at rs1800541was significantly associated with reduced risk of poor response to neoadjuvant chemotherapy, or chemoresistance (P<0.01),while the G allele at rs2070699was associated with increased risk of chemoresistance at a marginal significance level (P=0.06).4. rs1800541and rs2070699were in strong LD(cases, D’=0.940,r2=0.885; controls, D=0.925,r2=0.860).5.a2-SNP haplotype TG was significantly more common in cases than in controls (P=0.012;adjusted OR,1.82;95%CI,1.10-5.65),and a2-SNP haplotype GT was significantly more common in controls than in cases (P=0.009; adjusted OR,0.25;95%CI,0.14-0.84).6.In the chemical resistant over cases of bone tumor, bone tumor cell secretion of ET-1level and has significant negative correlation between the percentage of tumor necrosis. Conclusion:1.There was no correlation between tumor necrosis after chemotherapy and age,sex, distribution of tumor location and stage,body mass index, systolic blood pressure, diastolic blood pressure, and plasma ET-1levels in child and adolescent patients with OS.2.There was no significant correlation between rs5370and risk of chemoresistant of child and adolescent osteosarcoma.3.The Gallele at rs1800541was significantly associated with reduced risk of poor response to neoadjuvant chemotherapy, or chemoresistance, while the G allele at rs2070699was associated with increased risk of chemoresistance at a marginal significance level.4.rs1800541and rs2070699were in strong LD.5.The TG and the GT haplotypes were associated with increased and reduced risk of chemoresistant pediatric OS.6. In the chemical resistant over cases of bone tumor, bone tumor cell secretion of ET-1level and has significant negative correlation between the percentage of tumor necrosis.