Prostate cancer with different ERG status may show different FOXP3-positive cell numbers.

Prostatic carcinoma is the most frequent cancer in males in the Western world. A significant proportion of these cancers have a recurrent translocation involving ETS family genes, which leads to the overexpression of ERG transcription factor. Prostate cancers, which bear this mutation, differ in a number of features, including tumor microenvironment. One of the components of the tumor microenvironment is FOXP3 positive lymphocytes, which may participate in breaking immunosurveillance and promoting tumor growth. The aim of the study was to analyze the relationships between ERG expression, number of FOXP3 positive cells and other features of the tumor. The study group consisted of 65 cases. Tissue microarrays composed of 2 mm tissue cores were used for immunohistological evaluation. Immunohistochemistry for ERG and FOXP3 was performed according to the routinely applied protocol. The FOXP3 positive cells were counted and the results were expressed as the number of cells per mm2. The average number of FOXP3 positive cells was 33.30/mm2 for all cases, 21.43/mm2 for the ERG negative and 42.28/mm2 for the ERG positive group (p < 0.02). There were no significant relationships between FOXP3 positive cell count and any other parameters studied. Our results suggest that the immune response may differ between ERG negative and ERG positive prostatic carcinomas.

Mast cells influence neoangiogenesis in prostatic cancer independently of ERG status.

A significant proportion of prostatic adenocarcinomas show recurrent translocation leading to ERG expression. Previously we found that ERG+ cases have higher microvessel density than negative ones. One factor influencing angiogenesis in cancer is mast cells. The aim of the present study was to evaluate the relationship between microvessels, mast cells and ERG status. Tissue microarrays prepared from 113 radical prostatectomy specimens were analyzed with immunohistochemistry for CD31, tryptase and chymase. Vascular profiles and tryptase-positive and chymase-positive cells were counted. The average number of tryptase-positive cells was 28.93/mm2 and chymase-positive cells 9.91/mm2. The average number of CD31+ vascular profiles was 352.66/mm2. The average number of tryptase-positive cells was 26.35/mm2 for ERG- cases and 32.12/mm2 for ERG+ cases. The average number of chymase-positive cells was 8.14/mm2 for ERG- cases and 12.06/mm2 for ERG+ cases. The average number of CD31+ vascular profiles was 321.34/mm2 for ERG- cases and 390.74/mm2 for ERG+ cases. The number of CD31+ vascular profiles was positively correlated with the number of tryptase-positive and chymase-positive cells (R = 0.26 and R = 0.20). In summary, we demonstrated an interrelationship between mast cells, microvascular density and ERG status in prostatic carcinoma.

Mast cells in systemic and cutaneous lupus erythematosus.

Mast cells (MCs) are known to be regulators of inflammation and immunity, due to the released mediators and expressed cell surface molecules. Lupus erythematosus (LE) is a group of diseases which can be systemic or limited to the skin. Due to the fact that cytokines and chemokines produced by inflammatory cells contribute to the pathogenesis of LE, we quantified the number of mast cells present in the skin. The aim of the study was to compare the chymase-positive and tryptase-positive mast cell counts within skin biopsies from patients with systemic lupus erythematosus (SLE), discoid lupus erythematosus (DLE) and subacute cutaneous lupus erythematosus (SCLE). The material consisted of 45 skin biopsies: 6 with SLE, 34 with DLE and 5 with SCLE. Chymase- and tryptase-positive cells were stained by immunohistochemistry and counted. The mean count of chymase-positive mast cells was 85.14 hpf for the whole group, 35.83 for SLE, 88.48 for DLE and 121.6 for SCLE. The mean count of tryptase-positive cells was 120.05 hpf for the entire group, 59.17 for SLE, 126.42 for DLE and 149.8 for SCLE. The differences between groups were significant for chymase- and tryptase-positive cells.