Expression Of CD44v6 And Muc1 Protein In Thyroid Carcinoma And Their Significance

Objective: The carcinoma of thyroid is the common malignant neoplasm in human body, accounts for approximately 1% of systemic malignant tumor, the average incidence rate about 2 to 4 per 100,000 every year, in recent years, its incidence rate is increasing and the disease is more common in female patients. According to pathological type of thyroid carcinoma: it can be divided into four types which contains papillary carcinoma, follicular carcinoma, anaplastic carcinoma and medullary carcinoma. Except medullary thyroid carcinoma, most are originated from thyroid follicular epithelial cells. The occurrence and development of thyroid carcinoma is a compose complex process which composed of various factors and multiple steps. Occurrence in the process of thyroid carcinoma may be associated with the radiation injury, heredity and many other gene factors changes in the body.The distribution of CD44 protein is a very broad class of cell surface transmembrane glycoprotein , its main effect is to participate in the heterogeneity adhesion, to produce adhesion effect in the host cell and stroma to tumor cells,this effect to make it plays a promoting role in invasion and metastasis in malignant tumor cells. Human CD44 protein located in the short arm of chromosome 11, its span is about 50kb, is composed of 20 highly conserved exons, different lengths of introns insert in exons to separate them. According to the different ways of transcription, 20 exons of CD44 protein can be divided into two categories: standard (s) and variant (v). In different malignant tumor tissues, the positive expression rate of CD44v6 protein are different and the positive expression is more prone to occur local invasion and distant metastasis; the patients with positive expression in 5-year survival rate is lower and the prognosis is worse than the negative. Recently years, there are lots of research results show that CD44v6 protein plays an important role in the process of thyroid carcinoma lymphonodus metastasis; in clinical, the positive expression can be seen as an important assessable indicator in lymphonodus metastasis and prognosis.Mucin 1 (abbreviation MUC1) is a high glycosylated glycoprotein with large molecular weight, which is a transmembrane molecule, also called membrane attached protein. MUC1 protein can maintain the integrity of epithelial cells, plays a certain role in epithelial cells to renewal and differentiation, also participating in the occurrence and metastasis in malignant tumors. MUC1 in normal epithelial tissues play an important protective role, but in malignant tumor cells the fuction that can reduce adhesion between cancer cells to promote the adhesion of cancer cells to normal cells. MUC1 can also make the tumor cells evade immune system recognition by the phenomenon of hindered, which will help the cancer cells to transfer. So, MUC1 protein has played an important role in some malignant tumors'development, metastasis, therapy and prognosis, as a valid marker in some epithelial tumors with lymph node metastasis.This experiment was studied on the expression of CD44v6 and MUC1 in thyroid carcinoma tissues, to discuss their role and significance in the process of thyroid tumors'occurrence, development and metastasis, thus through these related tumor markers to feedback the presence in thyroid carcinoma, to help early diagnosis, treatment and evaluation of proposed treatment, and monitoring the prognosis of patients with thyroid carcinoma.Methods: Using immunohistochemical S-P method to respectively detect positive expression rate in 75 cases of thyroid carcinoma(among them, 59 cases for papillary carcinoma, 8 cases of follicular carcinoma, 2 cases for medullary carcinoma and 6 cases of anaplastic carcinoma) and 16 cases of thyroid adenoma paraffin section, to analyze the relationship in its positive expression rate of thyroid cancer metastasis and invasiveness.Results:1 The expression of CD44v6 protein in different thyroid tissues CD44v6 protein in thyroid adenoma and thyroid carcinoma, the positive rates were 18.8% (3 / 16) and 62.7% (47/75), explain that thyroid carcinoma in the expression is significantly higher than thyroid adenoma(χ2=10.274,P<0.05); there lymph node metastasis in the positive rate (23/28) was significantly higher than those without lymph node metastasis (24/47),(χ2=7.244,P<0.05); the positive expression of CD44v6 protein has statistical significance inⅠ~Ⅳperiod of thyroid cancer (χ2=17.348,P<0.05), its expression rates respectively are 48.3%, 75.0%, 94.1% and 22.2%.2 The expression of MUC1 protein in different thyroid tissuesMUC1 protein in thyroid adenoma and thyroid carcinoma, the positive rates were 25.0% (4 / 16) and 70.1% (53/75), explain that thyroid carcinoma in the expression is significantly higher than thyroid adenoma(χ2=11.751,P<0.05); the positive rate of MUC1 protein in lymph node metastasis (24/28) was significantly higher than those without lymph node metastasis (29/47),(χ2=4.881,P<0.05); inⅠ~Ⅳperiod of thyroid carcinoma, its expression rates are 62.0%, 80.0%, 88.2% and 44.4%, no statistical significance (χ2=7.391,P=0.060>0.05)Conclusion:1 The positive expression of CD44v6 protein is different in the benign and malignant thyroid tumor; and be associated with thyroid carcinoma of the clinical stages and lymph node metastasis.2 The positive expression of MUC1 protein is different in the benign and malignant thyroid tumor,may be related to the occurrence of thyroid carcinoma; MUC1 is concerned with thyroid carcinoma of the lymph node metastasis; but it has no significant relationship to the clinical stages of thyroid carcinoma.3 The expression of CD44v6 protein is correlated to the expression of MUC1 protein in thyroid carcinoma; both of them are playing an important role in the progression and metastasis in thyroid carcinoma.The expression on CD44v6 protein and MCU1 protein maybe have important clinical value on the judgement of benign and malignant thyroid tumor and degree of malignancy as well as to forecast the invasion and metastasis of cancer; they are perhaps seen as an important biological indicators to evaluate the prognosis of the malignant tumor patients.