Expression And Clinicopathological Features Correlation Studies Of Leptin And Leptin Receptor In Papillary Thyroid Carcinom

Thyroid cancer is a common endocrine malignancy, papillary thyroid cancer(PTC) accounts for approximately75%-85%. During the last several decades, theincidence of the thyroid cancer has been undergone a worldwide increase and has theserious in health.Adipocytokines have be closely related with tumor,especially leptinand adiponectin as the Yin-Yang adipokines have great significance for molecularmechanism of cancer.In1994, Zhang Y. discovered leptin at the RockefellerUniversity through the study of mice. And Tartaglia L. discovered its receptor (ObR)in1995. Many studies have shown consistently that leptin is associated with sometypes of cancer, such as breast cancer, ovary cancer, prostate cancer and so on. Butnow there is no obviously evidence that how does leptin work in PTC. So our study’spurpose is to examine the expression and clinicopathological features correlation ofLeptin and ObR in PTC tissue.And we study the expression of leptin and ObR and theaffection of leptin on growth and migration in PTC K1cell line, for offering a newidea for PTC’s molecular mechanism,gene therapy and prognosis.Objective our purpose is that the expression and the role of leptin on growthand migration in PTC, offering evidence of PTC’s molecular mechanism,genetherapy and prognosis.Methods Our study has two parts. The frist part is that the expression of leptinamd ObR was detected by immunohistochemistry (IHC) in PTC tissues and thyroidadenoma tissues, and analyse whether the expression of leptin amd ObR are association with clinical features such as tumor size, invasiveness, metastasis and soon. The second parts is that we the expression of leptin amd ObR was detected byRT-PCR and Western Blot on the level of mRNA and protien in PTC K1cell line. Wemeasured effect of leptin on PTC K1cell growth and migration using CCK-8assaryand transwell migration assary.Result By the IHC, we researched that the positive expression rates of leptinwere72.37%(55/76) and56.25%(9/16) in PTC and thyroid adenoma tissuesrespectively. The difference between the two groups was not significant (P>0.05).Thepositive expression rates of ObR were73.68%(56/76) and43.75%(7/16) in PTC andthyroid adenoma tissues. The difference between the two groups was significant(P<0.05). There is the positive correlation of leptin expression with ObR expression inthe PTC. In PTC tissues, the tumor size in leptin and ObR positive expressiongroups was obviously different with the negative expression groups’. The differenceswere significant (P<0.05). By the RT-PCR and Weatern Blot, we detected theexpression of leptin amd ObR on the level of mRNA and protien in PTC K1cells line.The result of CCK-8showed that high concentration leptin (25ng/ml，125ng/ml) couldpromote proliferation of PTC K1cells. The ability of k1cells to migrate was incresedwhen treated with high concentration leptin (25ng/ml，125ng/ml).