Immunohistochemical analysis of NaPi2b protein (MX35 antigen) expression and subcellular localization in human normal and cancer tissues.

AIM: To study the expression profile of the NaPi2b protein and its localization in breast, ovarian and lung cancer cells in relation to normal tissues adjacent to tumor. METHODS: Immunohistochemical analysis with monoclonal antibody MX35 was applied for investigation of NaPi2b protein expression in breast, lung and ovarian carcinomas. Intensity of NaPi2b protein expression was calculated with semiquantitative scores. RESULTS: NaPi2b (MX35) protein expression was detected in breast, lung and ovarian cancer cells and adjacent normal tissue. We have shown that in contrast to ovarian tumors in breast and lung tumors NaPi2b expression is down regulated comparing to correspondent normal tissues. CONCLUSION: This study provides the data on the pattern of NaPi2b expression and cellular localization in breast, lung and ovarian cancers, which might be useful for understanding the mechanism of transport and maintenance of inorganic phosphate in cancer and normal cells, as well as for developing novel immunotherapeutic approaches based on MX35 monoclonal antibody.

Quantitative analysis of SLC34A2 expression in different types of ovarian tumors.

AIM: The main purpose of this study was to estimate the SLC34A2 gene expression in normal ovary and different types of ovarian tumors. METHODS: We have investigated SLC34A2 gene expression level in papillary serous, endometrioid, unspecified adenocarcinomas, benign tumors, and normal ovarian tissues using real-time PCR analysis. Differences in gene expression were calculated as fold changes in gene expression in ovarian carcinomas and benign tumors compared to normal ovary. RESULTS: We have found that SLC34A2 gene was highly expressed in well-differentiated endometrioid and papillary serous ovarian carcinomas compared to low-differentiated endometrioid carcinomas, benign serous cystoadenomas and normal ovary. Analysis of SLC34A2 gene expression according to tumor differentiation level (poor- and well-differentiated) showed that SLC34A2 is up-regulated in well differentiated tumors. CONCLUSION: Upregulation of SLC34A2 gene expression in well-differentiated tumors may reflect cell differentiation processes during ovarian cancerogenesis and could serve as potential marker for ovarian cancer diagnosis and prognosis.