Expression of phosphatase of regenerating liver-3 (PRL-3) in endometrioid cancer and lymph nodes metastases.

PURPOSE: We identify the expression of PRL-3 in primary endometrioid endometrial cancer and metastases in relation to the clinicopathological characteristics. MATERIAL/METHODS: The study involved 30 patients with type I endometrial cancer. Twelve of them were diagnosed with metastases in various localization of abdomen. The PRL-3 expression was evaluated on the basis of immunohistochemistry results by the use of monoclonal antibody anti-PRL3 clone 3B6. RESULTS: The intensity of PRL-3 expression in correlation with tumor stage was statistically significant (p = 0.024). The strongest reaction was noted in cases classified as a 1a and 1b stage defined by FIGO. The strength of PRL-3 expression is significantly associated with the degree of histological tumor grade (p = 0.035). CONCLUSIONS: The strong expression of PRL-3 in the primary tumor that was significantly correlated with the grade and clinical stage suggest that PTP4A3 participates in the process of endometrial carcinogenesis.

Immunohistochemical assessment of PRL-3 (PTP4A3) expression in tumor buds, invasion front, central region of tumor and metastases of colorectal cancer.

PURPOSE: The aim of the study was to evaluate immunohistochemical expression of PRL-3 protein tumor buds, invasion front, central region of tumor and metastases of colorectal cancer. MATERIAL/METHODS: The PRL-3 expression was analyzed in 103 colorectal carcinoma patients, using the immunohistochemical method with a monoclonal antibody 3B6 anti-PRL-3 (Attogen Biomedical Research, USA). RESULTS: Positive reaction for PRL-3 was observed in 36.9% of cases in the central region of tumor, in 64.3% in the invasion front, and in as many as 81.4% in buds (present in 70/103 cases), in 100% in metastases to local lymph nodes, in 100% in metastases to the liver and in 97.1% in metastases to the lungs. The findings indicate that cancer cells obtain this protein already in the early stages of metastasizing. PRL-3 is present not only in metastases to local lymph nodes but also to distant organs. It is likely that PRL-3 protein takes part in the initiation of metastasizing of cancer cells. Also the presence of lymph and blood vessel invasion was found only to correlate with increased percentage of patients with strong PRL-3 expression in tumor buds (p=0.046). CONCLUSION: Our results may suggests the participation of PRL-3 protein as a marker of the presence of colorectal cancer metastasis to the lymph nodes and distant metastases, which is independent of parameters such as gender and age of the patients, tumor location, histological type and grade of histological malignancy and stage of tumor.