SLAMF1/CD150 expression and topology in prostate and breast cancer cell lines.

BACKGROUND: SLAMF1/CD150 receptor is aberrantly expressed in malignant hematopoietic cells compared to ubiquitous expression in their normal analogues. However, the data about CD150 expression and function outside the hematopoietic system are limited. The aim of this pilot study was to examine the profile of mRNA expression of CD150 isoforms and the protein topology in highly and low malignant breast (BC) and prostate cancer (PC) cell lines. MATERIALS AND METHODS: The study was performed on BC T47D, MDA-MB-231, ВСС/Р and BC/ML cell lines and PC LNCap, Du-145 and PC-3 cell lines. The quantitative polymerase chain reaction was applied for study of CD150 isoforms mRNA expression and flow cytometry was used for determination of protein localization. RESULTS: Analyzed BC cell lines did not express CD150 on the cell surface membrane (csCD150-), but more than 45% of cells were positive for CD150 cytoplasmic reaction (cyCD150+). The cyCD150 expression level in T47D cells of luminal BC subtype was higher than in basal BC cell lines MDA-MB-231, ВСС/Р and BC/ML. The PC cell lines expressed CD150 both on the cell surface and in cytoplasm. The highest number of csCD150+ and cyCD150+ cells was revealed in less aggressive androgen responsive, non-metastatic LNCap cell line. All studied BC and PC cell lines expressed mRNA of canonical transmembrane mCD150 and novel nCD150 isoforms but with different pattern of prevalence. Soluble CD150 isoform was revealed at the low level only in BCC/P BC cell line and LNCap, PC-3 PC cell lines. CONCLUSIONS: We have shown that BC and PC cell lines differentially expressed multifunctional receptor CD150 at the mRNA and protein levels that may indicate its association with the degree of their malignancy.

Influence of bacterial lectin on key regulatory links of functional activity of macrophages in mice with Ehrlich carcinoma.

BACKGROUND: Recent studies have shown the potential of using different approaches for immunotherapy in cancer treatment. Macrophages (Mph) are one of the promising targets for immunotherapy. AIM: To investigate changes in the functional activity of Mph in mice with Ehrlich carcinoma by nitric oxide (NO)/arginase (Arg), IRF4/IRF5 and STAT1/STAT6 ratios caused by administration of lectin from B. subtilis IMV-7724. MATERIALS AND METHODS: From the 2nd day after Ehrlich carcinoma inoculation into female Balb/c mice, lectin from B. subtilis IMV B-7724 (0.02 mg/mouse) was administered for 10 days. The peritoneal Mph were isolated on days 14, 21, and 28 after tumor transplantation and their functional state (NO production, Arg activity and cytotoxic activity) was examined. The levels of mRNA expression of transcription factors STAT-1, STAT-6, IRF5, IRF4 were evaluated. RESULTS: In lectin-treated animals with Ehrlich carcinoma, the functional state of Mph (NO/Arg ratio, index of cytotoxic activity) was maintained at the level of intact mice exceeding the values in untreated animals with Ehrlich carcinoma at late terms of tumor growth (21, 28 days). Analysis of mRNA expression levels of transcription factors in these animals showed a significant increase (p < 0.05) in the ratio of STAT1/STAT6 on the day 21 and IRF5/IRF4 on day 28 of tumor growth compared to that in untreated mice. CONCLUSIONS: Administration of lectin from B. subtilis IMV B-7724 to mice with Ehrlich carcinoma led to the prevalence of Mph exhibiting the functional properties of M1 type at late-term tumor growth. The transcription factors of the STAT and IRF signaling pathways are involved in the process of Mph polarization induced by lectin from B. subtilis IMV B-7724.