β-catenin与VEGF-C和-D在结直肠癌中的表达及其相关性

Significance of expression of E-cadherin and β-catenin in juvenile colorectal polyps in children

AIM: To detect the expression of E-cadherin and β-catenin mRNAs and proteins in human colorectal juvenile polyps (JP) in children.

METHODS: The expression of E-cadherin and β-catenin mRNAs and proteins in 22 juvenile colorectal polyp specimens and 8 normal colorectal specimens was assayed by real-time PCR and Western blot, respectively. Immunohistochemistry was used to determine the expression and localization of E-cadherin and β-catenin in 30 juvenile colorectal polyp specimens and 10 normal colorectal specimens.

RESULTS: Real-time PCR and Western blot analyses showed that the expression levels of E-cadherin mRNA and protein were significantly lower in juvenile colorectal polyps than in normal colorectal specimens (1.1526 ± 0.3801 vs 0.4094 ± 0.2305, P < 0.05; 0.6028 ± 0.1778 vs 0.3257 ± 0.1168, P < 0.05). Although there was no significant difference in the expression level of β-catenin mRNA between the two groups, the expression of β-catenin was significantly higher in juvenile colorectal polyps than in normal colorectal specimens (0.8010 ± 0.1380 vs 1.2064 ± 0.3587, P < 0.05). Immunohistochemistry indicates that E-cadherin expression was down-regulated in juvenile polyps compared with controls (102.5155 ± 25.2988 vs 53.5772 ± 15.3205, P < 0.05). Positive staining for E-cadherin was predominantly localized on the epithelial cell membrane. The expression of β-catenin was increased in juvenile polyp specimens (112.0805 ± 24 9572 vs 260.3554 ± 86.6987, P < 0.05), and the positive rates of membrane, cytoplasmic and nuclear staining in juvenile polyp tissue was significantly higher than those in normal control tissues.

CONCLUSION: Dysregulation of E-cadherin and β-catenin expression may be an important feature of juvenile colorectal polyps.

Correlation between β-catenin expression and recurrence and metastasis of primary hepatocellular carcinoma in patients after surgery

AIM: To examine the expression of β-catenin in hepatocellular carcinoma and to analyze its correlation with recurrence and metastasis of primary hepatocellular carcinoma in patients after surgery.

METHODS: Immunohistochemistry was used to detect the expression of β-catenin in tumor samples and matched tumor-adjacent tissue samples taken form patients who had recurrence and/or metastasis within one year after surgery for primary hepatocellular carcinoma and those had no recurrence or metastasis. The correlation between β-catenin expression and the clinicopathological characteristics of primary hepatocellular carcinoma was analyzed.

RESULTS: β-catenin was mainly distributed on the membrane of cells in tumor-adjacent tissue. The rate of aberrant expression of β-catenin was significantly higher in tumor tissue than in tumor-adjacent tissue (60% vs 15%, χ² = 17.28, P < 0.001). There was no significant difference in the expression of β-catenin in tumor-adjacent normal tissue between patients with and without cirrhosis (χ² = 0.388, P = 0.533). The rate of aberrant expression of β-catenin was significantly higher in primary hepatocellular carcinoma with recurrence and/or metastasis than in that without recurrence or metastasis (80.0% vs 40%, χ² = 6.667, P = 0.010). Aberrant expression of β-catenin was not correlated with age, liver cirrhosis, tumor size or differentiation, but was associated with the recurrence and metastasis of primary hepatocellular carcinoma.

CONCLUSION: Aberrant expression of β-catenin is associated with the development, recurrence metastasis of primary hepatocellular carcinoma and may be used as a useful prognostic parameter to predict overall survival.