The Roles Of Circulating LncRNA H19 And Its SNPs In Breast Cancer Diagnosis

The part 1Circulating of lnc RNA H19 in plasma as a potential biomarker for breast cancer diagnosisObjective: To investigate the expression of plasma lnc RNA H19 in breast cancer patients and identify its potential diagnosis values for breast cancer.Methods:H19 levels were firstly measured in 24 pairs of tissues and 30 pairs of plasma by using quantitative real-time PCR(q RT-PCR).Then,to further enlarge sample size to detect the expression leves of plasma H19 and analyze the correlations between plasma H19 and clinical characteristics in 97 patients with breast cancer.ECL immunoassay was performed to detect plasma CA15-3and CEA levels in 30 early patients of breast cancer.Receiver operating characteristic(ROC)curve and the multivariable logistic regression model was performed to evaluate the diagnostic values of plasma H19 in 24 early patients from healthy controls.Results:1.Compared to corresponding controls,the expressions of H19 were significantly increased in breast cancer tissues and plasma(P<0.05),and the expression levels of plasma H19 were correlated with estrogen receptor(ER),progesterone receptor(PR),c-erb B-2 and lymph node metastasis(P<0.05).2.The area under the ROC curve(AUC)was 0.81,with sensitivity andspecificity were 60.0% and 87.2%,respectively.The diagnostic capability and the specificity of plasma H19 much higher than that of conventional tumor marker CA153(AUC=0.66)and CEA(AUC=0.52)(P<0.0001),and the combined values(AUC=0.84)of plasma H19,CEA and CA153 greater predictability than H19 alone.3.The expression levels of plasma H19 were significantly decreased in postoperative samples than preoperative samples(P=0.0006).Conclusion: plasma H19 may serve as a potential biomarker for breast cancer diagnosis and monitoring tumor dynamics.The part 2Long non-coding RNA H19 polymorphisms contribute to susceptibility of breast cancerObjective: The aim of this study was to evaluate the association between H19 single nucleotide polymorphisms(SNPs)and the risk of breast cancer.Methods: We searched tag SNPs in lnc RNA H19 in the chromosomal region11p15.5 using hapmap(http://hapmap.ncbi.nlm.nih.gov/)with the selection criterion of a minor allele frequency>0.05 in the Chinese Han population.Finally,three tag SNPs(rs3741219,rs217727 and rs2107425)were genotyped in 500 BC patients and 500 healthy controls.These three tag SNPs were genotyped with polymerase chain reaction-restriction fragment-length polymorphism(PCR-RFLP)assays.Hardy–Weinberg equilibrium(HWE)was evaluated by a goodness-of-fit chi-squared(c2)-test to compare the observedgenotype frequencies with the expected ones among the cancerfree control subjects.Univariate and multivariate analysis were performed to evaluate the association between H19 polymorphisms and the risk of breast cancer.Results:1.Compared with the common genotype,rs217727 TT and rs2107425 AA genotypes were associated with significantly increased breast cancer risk(TT vs.CC: P=0.01,adjusted OR=1.38,95% CI=1.06-2.21;AA vs.GG: P=0.02,adjusted OR=1.58,95% CI=1.12-2.19,respectively).2.CT+TT genotypes of rs217727 had a significantly increased risk of breast cancer among women with number of pregnancy>2(OR=1.36,95%CI=0.87-1.99,P=0.04),and CT+TT genotype of rs217727 was associated with ER positivity(OR=1.77,95% CI=0.86-3.25,P=0.03).GA+AA genotypes of rs2107425 breast cancer risk increased in individuals carrying GA+AA genotypes and having had two or more abortions(OR=1.65,95% CI=1.12-3.26,P=0.02).However,no significant association were observed between the clinicopathological features and rs2107425 polymorphism.3.T to C base change at rs3741219 T>C may create hsa-mi R-1539 micro RNA(mi RNA)binding sites on H19.A single nucleotide polymorphism of lnc RNA may change the lnc RNA structure,affect the stability and influence the interaction of mi RNA-lnc RNA.Although the polymorphism of rs217727 C>T did not affect H19 m RNA expression levels,mutation may alter the translational efficiency,potentially leading to alterations in H19 structure,which may ultimately influence the function of H19.Conclusion:The etiology of breast cancer is associated with genetic and reproductive factors.H19 SNPs(rs217727 C>T and rs2107425G>A)were significantly associated with increased risk of breast cancer.Furthermore,the mutation of rs217727 C>T polymorphism is functional,modulating susceptibility to breast cancer by altering the translational efficiency.