Expression Of Wild And Variant Estrogen Receptor α In Hepatits B Virus Related HCC And Clinical Significance

Hepatitis B virus（HBV） infection is a serious public health problem in the world,China is the high incidence of HCC. Chronic HBV infection is a major risk factor for HCC,about more than70%of HCC patients suffered from HBV. At the same time, HCC issexually dimorphic in humans, with signifcantly higher incidence in males, an effect that isdependent on sex hormones and their receptors across studies. Male to female ratio is about5-10:1in China. The prognosis of severe hepatitis, liver cirrhosis, HCC in male patients ispoor, as well as, the female patients with HCC both natural survival rate and resectionsurvival rate were higher than male. Factors that cause HCC gender differences have beenconsidered the key to reveal its pathogenesis. Epidemiological and experimental evidenceshows that HCC is one of the sex hormone sensitive tumor, the same as the breast andprostate cancer.A large number of studies suggested that estrogen play an important role in theoccurrence and development of HCC. Estrogen played effect by combining with its specificreceptors(estrogen receptor), estrogen receptor (ER) mainly includes and β subtypes. Ourpreliminary work had found that the haplotype29C-IVS1-401C of ER increased theclearance of HBV infection, as well as reduced the susceptibility of HBV related livercirrhosis and HCC. Wang et al.found that ER could reduce HBV gene transcriptionthrough interaction with hepatocyte nuclear factor-4.Therefore, it further confired that ERplayed an important role in the occurrence of HBV related liver disease.In1998,Villa et al, found that ER5(estrogen receptor exon deletion5) expressionin HCC tissues, and its expression related with the prognosis of HCC patients. However, inChina about this subject is less, especially there is no report about ER5proteinexpression in HCC tissue. Therefore, we detected the expression of ER and its variant inHBV related liver disease by immunohistochemistry, RT-PCR and Western blot, in order toinvestigate its role in the development of HBV related liver disease, as well as, provided theoretical basis of endocrine therapy and prognosis judgement.This research is divided into three parts.The first part, we studied the expressionpatterns of ER and ERβ in HBV related HCC by immunohistochemical and Western blot,ER and ERβ relationship with clinical and pathological characteristics of HBV relatedHCC was analyzed statistically．The second part,we studied the expression patterns of ERand its variant in HBV related HCC, peritumorand and chronic hepatitis B liver tissue byRT-PCR, TA cloning sequencing research, further, determined the variant types of ER. Thethird part, we produced ER5specific antibody, studied the expression patterns of ER5in HBV related HCC, peritumorand and chronic hepatitis B liver tissue byimmunohistochemistry and Western blot, as well as, ER5relationship with clinical andpathological characteristics of HBV related HCC was analyzed statistically．Result1. The ER was expressed in the cytoplasm, the positive expression rate of ER was35.7%. There was higher ER expression in tumor with diameter≤5cm and TNM stage I～Ⅱthan in tumor with diameter>5cm(P=0.006) and TNM stage Ⅲ～Ⅳ(P=0.011). ERexpress displayed no significance association with sex, age, serum AFP level, pathologicsubtype, and nodule number (P>0.05).2. ERβ was also expressed in the cytoplasm. ERβ express displayed no significanceassociation with age, sex, pathologic subtype, tumor diameter size, TNM stage, Nodulenumber and AFP level.3. The mRNA expression rate of ER wild type in HBV related HCC, peritumor andchronic hepatitis B tissue were100%,88.2%and77.8%, there was no statisticallysignificant difference between them(P>0.05).4. The mRNA of ER5had been detected in HBV related HCC, peritumor andchronic hepatitis B tissue. The mRNA expression rate of ER5were76.5%,76.5%and38.9%in HCC, peritumor and chronic hepatitis B tissue respectively, the difference hasstatistically significant (χ2=7.169, P=0.025).5. ER5as also expressed in the cytoplasm. The positive expression of ER5were67.2%,50%and25%in HBV related HCC, peritumor and normal liver tissuerespectively.ER5expression displayed significant association with HCC, peritumor andchronic hepatitis B (χ2=7.308, P=0.026). 6. The positive expression rate of ER5proteins were88.2%,76.5%and61.1%inHBV related HCC, peritumor and chronic hepatitis B, respectively. ER5expression wasno significant association with HCC, peritumor and chronic hepatitis B.(χ2=3.460, P=0.177).Conclusion1. ER and ERβ had expressed in HBV related HCC, peritumor and chronic hepatitisB tissues, and both ER and ERβ were expressed in cytoplasm.2. ER was differentially expressed in HBV related HCC. There was correlationbetween ER expression and tumor diameter and TNM stage. It suggested that the positiveexpression rate of ER had reduced with development of HCC.3. The ER5was expressed in HBV related HCC, peritumor and chronic hepatitis Btissues, in addition, the mRNA and protein expression of ER5were significantly higherin HCC than chronic hepatitis B and normal liver tissue, it suggested that ER5might playan important role in the occurrence of hepatits B-related hepatocellular carcinoma.