The clinical significances of the abnormal expressions of Piwil1 and Piwil2 in colonic adenoma and adenocarcinoma

OBJECTIVE The objective of the present investigation was to study the clinical significances of the abnormal expressions of Piwil1 and Piwil2 protein in colonic adenoma and adenocarcinoma. METHODS This study had applied immunohistochemical method to detect 45 cases of tissues adjacent to carcinoma (distance to cancerous tissue was above 5 cm), 41 cases of colonic adenoma and 92 cases of colon cancer tissues, and their Piwil1 and Piwil2 protein expression levels. ANALYSIS The correlation of both expression and its relationship with clinicopathological features of colon cancer was analyzed. RESULTS Positive expression rates of Piwil1 in tissues adjacent to carcinoma, colonic adenoma, and colon cancer were 11.1% (5/45), 53.7% (22/41), and 80.4% (74/92), respectively; the expression rates increased, and the comparisons between each two groups were statistically significant (P<0.05). In each group, the positive expression rates of Piwil2 were 24.4% (11/45 cases), 75.6% (31/41 cases), and 92.4% (85/92 cases); expression rates increased, and the comparisons between each two groups were statistically significant (P<0.05). Piwil1 expression and the correlation of the degree of differentiation, TNM stage, and lymph node metastasis were statistically significant (P<0.05). Piwil2 expression and the correlation of the degree of differentiation, tumor node metastasis (TNM) stage, and lymph node metastasis had no statistical significance (P>0.05). In colon cancer tissue, Piwil1 and Piwil2 expressions were positively correlated (r=0.262, P<0.05). CONCLUSION The results showed that the abnormal expression of Piwil1 and Piwil2 might play an important role in the process of colon cancer development.