The Clinical Significance Of TXNIP Expression In Papillary Thyroid Carcinoma

Objectives: Thyroid cancer is the most common malignant tumor in otolaryngology-head and neck surgery. It is well known that cell apoptosis is significantly related to carcinogenesis. Imbalance of cells in proliferation and apoptosis play important roles in the development and progression of cancer. Apoptosis is regulated by serial of genes and their productions. With improvement of human living standards, changes in lifestyle and dietary structure, there is an upward tendency in morbidity and mortality of colorectal carcinoma in the world. There is an important significance to clinical treatment to study the mechanisms of papillary thyroid carcinoma.Thioredoxin interaction protein(TXNIP) or thioredoxin binding protein-2(TBP-2), also called vitamin D3 upregulated protein 1(VDUP-1) was found in 1, 25-OH-vitamin D3 treated HL- 60 leukemia cells. It can directly bind to the catalytic active center of reduced thioredoxin and inhibits both its expression and activity. TRX/TXNIP system play an important roles in regulating cellular redox status. Oxidative stress, resulting from excessive production or accumulation of reactive oxygen species(ROS), has been implicated in both carcinoma pathology and anti-carcinoma therapy. It has been identified as a tumor suppressor gene in various solid tumors(such as, hepatocellular carcinoma, breast carcinoma and bladder carcinoma) and hematological malignancies.So far, the relationship between the TXNIP expression and papillary thyroid carcinoma has not been reported. This study investigated TXNIP expression in papillary thyroid carcinoma and the relationship with the Bcl-2, Bax expression, and meanwhile analysis the relationship among the TXNIP, Bcl-2, Bax expression with clinical indicators.Methods: We selected 64 papillary thyroid carcinoma specimens as experimental group, and 26 normal thyroid tissues as control group. TXNIP, Bcl-2 and Bax protein expression was detected by immunohistochemistry(SP) and Western blot. We also analysed the expression of TXNIP, Bcl-2 and Bax protein and the relationship among the patients’ age, gender, invasion and lymph node metastasis.Results:1 The expression of TXNIP, Bcl-2 and Bax in papillary thyroid carcinoma tissues and normal thyroid tissues using immunohistochemistry.There were 22 cases TXNIP protein positive expression in 26 normal tissues, the expression rate was 84.6%. There were 18 cases TXNIP protein positive expression in 64 thyroid papillary carcinoma cases, the positive expression rate was 26%. The X2 analysis result showed that TXNIP and Bax protein positive expression rate in papillary thyroid carcinoma tissues was significantly lower than that in normal thyroid tissues(P<0.05).There was Bcl-2 positive expression both in normal thyroid tissues and papillary thyroid carcinoma tissues. There were 6 cases Bcl-2 positive expression in 26 normal thyroid tissues, the expression rate was 23.1%. There were 41 cases Bcl-2 protein positive expression in 64 papillary thyroid carcinoma cases, the positive expression rate was 64.1%. After statistical analysis, the Bcl-2 expression in papillary thyroid carcinoma tissues was significantly higher than that in the normal thyroid tissues(P<0.05).There was Bax positive expression both in normal thyroid tissues and papillary thyroid carcinoma tissues. There were 17 cases Bax positive expression in 26 normal thyroid tissues, the expression rate was 65.4%. There were 22 cases Bax protein positive expression in 64 papillary thyroid carcinoma cases, the positive expression rate was 34.4%. After statistical analysis, the Bax expression in papillary thyroid carcinoma tissues was significantly lower than that in the normal thyroid tissues(P<0.05).2 The expression of TXNIP, Bcl-2 and Bax in papillary thyroid carcinoma tissues and normal thyroid tissues using Western blotTXNIP protein relative expression intensity in papillary thyroid carcinoma tissues was significantly lower than that in normal thyroid tissues(P<0.05). The Bcl-2 protein expression relative intensity in papillary thyroid carcinoma tissue was significantly higher than that in normal thyroid tissues(P<0.05). Bax protein relative expression intensity in papillary thyroid carcinoma tissues was significantly lower than that in normal thyroid tissues(P<0.05).3 The relationship between TXNIP, Bcl-2 and Bax protein expression and clinicopathologic parameters in papillary thyroid carcinomaTXNIP positive expression rate(18.2%) in papillary thyroid carcinoma tissues with lymph node metastasis was significantly lower than that(29.3%) in no lymph node metastasis, the difference has statistical significant. The expression of TXNIP has no relationship with patients’ gender and age of tumor(P>0.05).The Bcl-2 expression rates in papillary thyroid carcinoma tissues, with no lymph node metastasis thyroid papillary carcinoma tissues were 71.7%, significantly higher than those(27.3%) with lymph node metastasis papillary thyroid carcinoma tissues(P<0.05). The expression of Bcl-2 has no relationship with patients’ gender and age of tumor(P>0.05).The Bax expression rates in papillary thyroid carcinoma tissues, with no lymph node metastasis thyroid papillary carcinoma tissue were 28.3%, significantly lower than those(63.6%) with lymph node metastasis papillary thyroid carcinoma tissues(P<0.05). The expression of Bax has no relationship with patients’ gender and age of tumor(P>0.05).4 The correlation between TXNIP, Bcl-2 and Bax expression in papillary thyroid carcinomaCorrelation analysis showed that the expression of TXNIP protein had negative correlation with Bcl-2 protein in papillary thyroid carcinoma tissues(P < 0.05), and had positive correlation with Bax protein in papillary thyroid carcinoma tissues(P<0.05).Conclusion:1 The expression of TXNIP in papillary thyroid carcinoma tissues was lower than that in normal thyroid tissues. The expression of TXNIP has relationship with lymph node metastasis in papillary thyroid carcinoma. The expression of TXNIP has no relationship with patients’ gender and age of tumor.2 The Bcl-2 protein expression in papillary thyroid carcinoma tissues was higher than that in normal thyroid tissues. The expression of Bcl-2 has relationship with lymph node metastasis in papillary thyroid carcinoma. The expression of Bcl-2 has no relationship with patients’ gender and age of tumor.3 The Bax protein expression in papillary thyroid carcinoma tissues was lower than that in normal thyroid tissues. The expression of Bax has relationship with lymph node metastasis in papillary thyroid carcinoma. The expression of Bax has no relationship with patients’ gender and age of tumor.4 The expression of TXNIP protein has negative correlation with Bcl-2 protein in papillary thyroid carcinoma. The expression of TXNIP protein has positive correlation with Bax protein in papillary thyroid carcinoma.