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Abstract Background Pyloric gland adenoma consists of closely packed pyloric-type glands lined by mucus-secreting cells. To date, approximately 230 cases have been reported, mostly of gastric localization with a tumour size up to 3.5 cm and a mean age of occurrence around 70 years. Adenocarcinoma develops in about 40% of cases and may be difficult to detect due to relatively mild nuclear atypia. Case presentation We present the first case of a pyloric gland adenoma of the cystic duct in a 62-year-old male patient and demonstrate the clinicopathologic characteristics, including radiographic, molecular, and cytogenetic findings. The 2 cm-tumour developed in the cystic duct and protruded into the hepatic and common bile duct. On microscopic examination, it displayed closely packed pyloric-type glands, and focal architectural distortion with mild nuclear atypia. Immunohistochemically, it expressed MUC1, MUC5AC, MUC6 and p53, but not MUC2 and CD10. The Ki67-proliferation index was 25%. Furthermore, high-grade intraepithelial neoplasia was observed in the surrounding bile duct. We detected chromosomal gains at 7p, 7q11q21, 15q, 16p, 20, losses at 6p23pter, 6q, 18, and amplifications at 1q and 6p21p22 in the pyloric gland adenoma by comparative genomic hybridization. A KRAS codon 12 mutation (c.35G>T; p.G12V) was detected in the pyloric gland adenoma and in the adjacent dysplasia by sequencing analysis. The diagnosis of pyloric gland adenoma was established with transition into well-differentiated adenocarcinoma and high-grade biliary intraepithelial neoplasia. Conclusion Pyloric gland adenoma evolving in the cystic duct is a rare differential diagnosis of obstructive bile duct tumours. Other premalignant bile duct lesions may be associated. Due to the risk of developing adenocarcinoma, surgical resection should be performed.

Abstract Background Renal cell carcinoma (RCC) represents one of the most immunoresponsive cancers. Antigen-specific vaccination with dendritic cells (DCs) in patients with metastatic RCC has been shown to induce cytotoxic T-cell responses associated with objective clinical responses. Thus, clinical trials utilizing DCs for immunotherapy of advanced RCCs appear to be promising; however, detailed analyses concerning the distribution and function of DC subsets in RCCs are lacking. Methods We characterized the distribution of the different immature and mature myeloid DC subsets in RCC tumour tissue and the corresponding normal kidney tissues. In further analyses, the expression of various chemokines and chemokine receptors controlling the migration of DC subsets was investigated. Results The highest numbers of immature CD1a+ DCs were found within RCC tumour tissue. In contrast, the accumulation of mature CD83+/DC-LAMP+ DCs were restricted to the invasive margin of the RCCs. The mature DCs formed clusters with proliferating T-cells. Furthermore, a close association was observed between MIP-3α-producing tumour cells and immature CCR6+ DC recruitment to the tumour bed. Conversely, MIP-3β and SLC expression was only detected at the tumour border, where CCR7-expressing T-cells and mature DCs formed clusters. Conclusion Increased numbers of immature DCs were observed within the tumour tissue of RCCs, whereas mature DCs were found in increased numbers at the tumour margin. Our results strongly implicate that the distribution of DC subsets is controlled by local lymphoid chemokine expression. Thus, increased expression of MIP-3α favours recruitment of immature DCs to the tumour bed, whereas de novo local expression of SLC and MIP-3β induces accumulation of mature DCs at the tumour margin forming clusters with proliferating T-cells reflecting a local anti-tumour immune response.

Abstract Background Mixed epithelial and stromal tumour (MEST) represents a recently described benign composite neoplasm of the kidney, which predominantly affects perimenopausal females. Most tumours are benign, although rare malignant cases have been observed. Case report A 47-year-old postmenopausal female presented to the urologist with flank pain. A CT scan of the abdomen showed a 30-mm-in-diameter uniform mass adjacent to the pelvis of the left kidney. Surgical exploration showed a tumour arising from the lower anterior hilus of the left kidney. The tumour could be excised by preserving the kidney. By intraoperative frozen section the tumour showed characteristic features of MEST with epithelial-covered cysts embedded in an "ovarian-like" stroma. Additional immunohistochemistry investigations showed expression for hormone receptors by the stromal component of the tumour. Discussion MEST typically presents in perimenopausal women as a primarily cystic mass. Commonly, the tumour arises from the renal parenchyma or pelvis. The tumour is composed of an admixture of cystic and sometimes more solid areas. The stromal cells typically demonstrate an ovarian-type stroma showing expression for the estrogen and progesterone receptors. Conclusion MEST represents a distinctive benign tumour entity of the kidney, which affects perimenopausal woman. The tumour should be distinguished from other cystic renal neoplasms. By imaging studies it is difficult to distinguish between a benign or malignant nature of the tumour. Thus, intraoperative frozen section is necessary for conservative surgery, since the overall prognosis is favourable and renal function can be preserved in most cases.

Context.--The addition of cetuximab to first-line chemotherapy substantially prolonged survival in patients with advanced non-small cell lung cancer whose tumors expressed high levels of epidermal growth factor receptor (EGFR; immunohistochemistry score of > 200 on a scale of 0-300). Objective.--To evaluate the interobserver reproducibility of this EGFR immunohistochemistry scoring system, based on both the tumor cell membrane staining intensity (graded 0-3+) and the percentage of cells staining at each intensity. Design.--In parts 1 (initial feasibility study) and 2 of this 2-part round robin test, sections of different non-small cell lung cancer tissue microarrays were stained in a central reference laboratory. Following reference evaluation, EGFR expression in 30 selected tumor cores was characterized in serial sections by lung cancer pathology specialists. The reproducibility of scoring by different raters was assessed. Analysis of between-rater agreement was based on the allocation of EGFR immunohistochemistry scores into low(200) EGFR expression groups. Results.--After discussion with raters of the issues impacting reproducibility identified in part 1 and following adjustment of processes, part 2 of the round robin test showed a high interobserver agreement in EGFR immunohistochemistry scoring, with an overall concordance rate of 90.9% and a mean coefficient of 0.812. Specimens with a reference EGFR immunohistochemistry score of lower than 200 and of 200 or higher showed mean concordance rates of 94.7% and 85.6%, respectively. Conclusions.--After appropriate training, assessing EGFR expression by this immunohistochemistry-based method allowed a highly reproducible allocation of non-small cell lung cancers into clinically relevant high- or low-EGFR expression groups. (Arch Pathol Lab Med. 2013;137:1255-1261; doi: 10.5858/arpa.2012-0605-OA), Cetuximab is a therapeutic monoclonal antibody targeting the epidermal growth factor receptor (EGFR) protein. The randomized phase III First-Line Erbitux in Lung Cancer (FLEX) study showed that the addition of [...]

Background: Renal cell carcinoma (RCC) represents one of the most immunoresponsive cancers. Antigen-specific vaccination with dendritic cells (DCs) in patients with metastatic RCC has been shown to induce cytotoxic T-cell responses associated with objective clinical responses. Thus, clinical trials utilizing DCs for immunotherapy of advanced RCCs appear to be promising; however, detailed analyses concerning the distribution and function of DC subsets in RCCs are lacking. Methods: We characterized the distribution of the different immature and mature myeloid DC subsets in RCC tumour tissue and the corresponding normal kidney tissues. In further analyses, the expression of various chemokines and chemokine receptors controlling the migration of DC subsets was investigated. Results: The highest numbers of immature CD1a+ DCs were found within RCC tumour tissue. In contrast, the accumulation of mature CD83+/DC-LAMP+ DCs were restricted to the invasive margin of the RCCs. The mature DCs formed clusters with proliferating T-cells. Furthermore, a close association was observed between MIP-3aproducing tumour cells and immature CCR6+ DC recruitment to the tumour bed. Conversely, MIP-3β and SLC expression was only detected at the tumour border, where CCR7-expressing T-cells and mature DCs formed clusters. Conclusion: Increased numbers of immature DCs were observed within the tumour tissue of RCCs, whereas mature DCs were found in increased numbers at the tumour margin. Our results strongly implicate that the distribution of DC subsets is controlled by local lymphoid chemokine expression. Thus, increased expression of MIP-3α favours recruitment of immature DCs to the tumour bed, whereas de novo local expression of SLC and MIP-3β induces accumulation of mature DCs at the tumour margin forming clusters with proliferating T-cells reflecting a local anti-tumour immune response. [ABSTRACT FROM AUTHOR]

Background: Mixed epithelial and stromal tumour (MEST) represents a recently described benign composite neoplasm of the kidney, which predominantly affects perimenopausal females. Most tumours are benign, although rare malignant cases have been observed. Case report: A 47-year-old postmenopausal female presented to the urologist with flank pain. A CT scan of the abdomen showed a 30-mm-in-diameter uniform mass adjacent to the pelvis of the left kidney. Surgical exploration showed a tumour arising from the lower anterior hilus of the left kidney. The tumour could be excised by preserving the kidney. By intraoperative frozen section the tumour showed characteristic features of MEST with epithelial-covered cysts embedded in an "ovarian-like" stroma. Additional immunohistochemistry investigations showed expression for hormone receptors by the stromal component of the tumour. Discussion: MEST typically presents in perimenopausal women as a primarily cystic mass. Commonly, the tumour arises from the renal parenchyma or pelvis. The tumour is composed of an admixture of cystic and sometimes more solid areas. The stromal cells typically demonstrate an ovarian-type stroma showing expression for the estrogen and progesterone receptors. Conclusion: MEST represents a distinctive benign tumour entity of the kidney, which affects perimenopausal woman. The tumour should be distinguished from other cystic renal neoplasms. By imaging studies it is difficult to distinguish between a benign or malignant nature of the tumour. Thus, intraoperative frozen section is necessary for conservative surgery, since the overall prognosis is favourable and renal function can be preserved in most cases. [ABSTRACT FROM AUTHOR]

Summary: Diagnosis of primary spindle cell tumors of the spleen is challenging because of the limited immunologic and cytogenetic characterization of this rare entity. We report a case of primary follicular dendritic cell (FDC) sarcoma of the spleen in a 44-year-old woman. Indications for FDC included positive staining for CD21, Ki-M4P, CD14, and fascin. Expression of both standard FDC markers CD23 and CD35 was detected immunohistochemically using tyramide signal amplification. Cytogenetic analysis revealed multiple clonal chromosomal aberrations involving unbalanced translocations of chromosomes X, 3, 5, 7, 8, 9, and 10, leading to net gains at 3q, 7p, 8q, and 9q and net losses at Xp, 8p, 9p, and 10p. Loss at Xp has been described previously in another tumor with FDC features, suggesting that this aberration might play a common role in this malignancy. [Copyright &y& Elsevier]

What is your diagnosis? [ABSTRACT FROM AUTHOR]

Interleukin-16 is a soluble ligand to the CD4 molecule with chemotactic properties for CD4+ cells and a competence growth factor for CD4+ T cells, upregulating HLA-DR and the interleukin-2 receptor CD25. There is also evidence for a synergistic effect of interleukin-16 and interleukin-2 on the activation of CD4+ T cells. The infiltrate in mycosis fungoides, the most common cutaneous T cell lymphoma, is typically CD4+. We tested the possibility that interleukin-16 is involved in the formation and progression of these lesions. By reverse transcription–polymerase chain reaction, interleukin-16 mRNA was detected in 18 of 18 mycosis fungoides lesions investigated. By competitive reverse transcription–polymerase chain reaction, interleukin-16 mRNA expression increased with disease stage. Secreted interleukin-16 was detected by enzyme-linked immunosorbent assay in both Th1- and Th2-like T cell clones (as characterized by their production of interferon-γ and interleukin-4) grown from lesional dermis and epidermis. By immunohistochemistry and in situ hybridization, infiltrating lymphocytes were the main producers of interleukin-16 whereas keratinocytes and endothelial cells remained negative. Atypical cells with convoluted nuclei were also positive. In advanced mycosis fungoides stages, many blast-like cells were positive, but some larger blasts remained negative. Interleukin-16 expression correlated positively with the expression of interleukin-2 and its receptor CD25 in individual skin lesions. Interleukin-2 expression, however, was weak or absent in samples from uninvolved skin, healthy controls and lesional psoriasis. Given the biologic properties of interleukin-16 and the parallel activation of the interleukin-2/CD25 pathway, interleukin-16 might be involved in the recruitment and stimulation of CD4+ lymphocytes in mycosis fungoides lesions and therefore contribute to the perpetuation of the... [ABSTRACT FROM AUTHOR]

Abstract: Introduction: The phase III SATURN study demonstrated that first-line maintenance erlotinib extended progression-free survival (PFS) and overall survival (OS) versus placebo in patients with advanced non-small cell lung cancer (NSCLC). Analysis of epidermal growth factor receptor (EGFR) expression by immunohistochemistry (IHC) found no significant interaction between EGFR IHC status and PFS (p =0.63) or OS (p =0.52). The FLEX study of first-line cetuximab plus chemotherapy demonstrated that EGFR IHC expression was predictive of improved OS with cetuximab when assessed by H-score with a magnification rule. This novel method was used to reassess samples from SATURN. Methods: The H-score method assigned a score of 0–300 to each patient, based on the percentage of cells stained at different intensities viewed at various magnifications. The discriminatory threshold was set at 200, per the FLEX study, and existing samples were re-read and classed as low (H-score<200) or high (≥200) EGFR expression. PFS and OS were re-analyzed based on these new classifications. Results: In the overall and EGFR wild-type populations, erlotinib provided a consistent survival benefit versus placebo. Hazard ratios (HRs) in the overall population were similar between EGFR IHC-positive and -negative patients for median PFS (HR 0.68 [95% confidence interval (CI) 0.53–0.86] and 0.76 [95% CI 0.62–0.93], respectively) and OS (HR 0.80 [95% CI 0.62–1.05] and 0.80 [95% CI 0.64–1.01] for IHC-positive and IHC-negative, respectively). In the EGFR wild-type population, HRs were again similar between EGFR IHC-positive and -negative subpopulations for PFS (HR 0.69 [95% CI 0.51–0.95] and 0.84 [95% CI 0.63–1.12], respectively) and OS (HR 0.78 [95% CI 0.55–1.10] and 0.76 [95% CI 0.55–1.05], respectively). Conclusions: These data suggest that EGFR IHC does not have value as a marker to predict erlotinib benefit in the first-line maintenance setting for advanced NSCLC. [Copyright &y& Elsevier]

Context.--The addition of cetuximab to first-line chemotherapy substantially prolonged survival in patients with advanced non-small cell lung cancer whose tumors expressed high levels of epidermal growth factor receptor (EGFR; immunohistochemistry score of ≥200 on a scale of 0-300). Objective.--To evaluate the interobserver reproducibility of this EGFR immunohistochemistry scoring system, based on both the tumor cell membrane staining intensity (graded 0-3+) and the percentage of cells staining at each intensity. Design.--In parts 1 (initial feasibility study) and 2 of this 2-part round robin test, sections of different non-small cell lung cancer tissue microarrays were stained in a central reference laboratory. Following reference evaluation, EGFR expression in 30 selected tumor cores was characterized in serial sections by lung cancer pathology specialists. The reproducibility of scoring by different raters was assessed. Analysis of between-rater agreement was based on the allocation of EGFR immunohistochemistry scores into low- (<200) and high- (≥200) EGFR expression groups. Results.--After discussion with raters of the issues impacting reproducibility identified in part 1 and following adjustment of processes, part 2 of the round robin test showed a high interobserver agreement in EGFR immunohistochemistry scoring, with an overall concordance rate of 90.9% and a mean coefficient of 0.812. Specimens with a reference EGFR immunohistochemistry score of lower than 200 and of 200 or higher showed mean concordance rates of 94.7% and 85.6%, respectively. Conclusions.--After appropriate training, assessing EGFR expression by this immunohistochemistry-based method allowed a highly reproducible allocation of non- small cell lung cancers into clinically relevant high- or low-EGFR expression groups. [ABSTRACT FROM AUTHOR]

Abstract: Objective: Cardiac surgery on cardiopulmonary bypass (CPB) results in progressive myocardial dysfunction, despite unimpaired coronary blood flow, and is associated with increased myocardial tumor necrosis factor-α (TNFα) expression. We investigated whether anti-inflammatory treatment prevents increased TNFα expression and myocardial dysfunction after CPB. Methods and results: Baseline systemic hemodynamics, myocardial contractile function, aortic and coronary blood flow were measured in anesthetized pigs. Then, placebo (PLA; saline; n =7) or methylprednisolone (MP; 30mg/kg; n =6) was infused intravenously and CPB was instituted. Global ischemia was induced for 10min by aortic cross-clamping, followed by 1h of cardioplegic cardiac arrest. After declamping and reperfusion, CPB was terminated after a total of 3h. Measurements were repeated at 15min, 4h, and 8h following termination of CPB. Systemic TNFα-plasma concentrations and left ventricular TNFα expression were analyzed. With unchanged coronary blood flow in both groups, a progressive loss of myocardial contractile function to 38±2% of baseline (p <0.01) and cardiac index to 48±6% of baseline (p <0.01) at 8h after CPB in PLA was attenuated in MP (myocardial function: 72±3%, p <0.01 vs PLA; cardiac index: 78±6%, p <0.05 vs PLA). Systemic TNFα was increased at 8h in PLA compared to MP (243±34 vs 90±34pg/ml, p <0.05). Myocardial TNFα was increased at 8h after CPB compared to baseline and MP (p <0.05). Myocardial TNFα immunostaining was more pronounced in PLA than in MP (p <0.05), with TNFα-mRNA localization predominantly to cardiomyocytes. Conclusions: Methylprednisolone attenuates both systemic and myocardial TNFα increases and progressive myocardial dysfunction induced by cardiac surgery, suggesting a key role for TNFα. [Copyright &y& Elsevier]

The cellular sarcoma gene (SRC) is a proto-oncogene encoding for a tyrosine kinase. SRC expression was determined in locally advanced rectal adenocarcinoma tissue from pretreatment biopsies and resection specimens. The expression level was correlated with clinicopathological parameters to evaluate the predictive and prognostic capacity. For this monocentric analysis 186 patients with locally advanced rectal cancer (median: 63.7 years; 130 men (69.9%), 56 women (30.1%)) were included. Patients with a carcinoma of the upper third of the rectum were treated with primary tumor resection (n=27; 14.5%). All other patients received a preoperative chemoradiotherapy (CRT) with 50.4 Gy and concomitant 5-fluorouracil (5-FU) or 5-FU+oxaliplatin followed by postoperative chemotherapy with 5-FU or 5-FU+oxaliplatin. SRC expression was determined with immunohistochemical staining from pretreatment biopsies (n=152) and residual tumor tissue from the resection specimens (n=163). The results were correlated with clinicopathological parameters and long-term follow-up. The expression of SRC was determined in pretherapeutic biopsies (mean H-Score: 229) and resection specimens (mean H-Score: 254). High SRC expression in pretherapeutic tumor samples significantly correlated with a negative postoperative nodal status (p=0.005). Furthermore an increased protein expression in residual tumor tissue was associated with fewer distant metastases (p=0.04). The overexpression of SRC in pretreatment tumor biopsies showed also a trend for a longer cancer-specific survival (CSS; p=0.05) and fewer local relapses (p=0.06) during long-term follow-up. High SRC expression in rectal cancer seems to be associated with a better long-term outcome. This finding could help in the future to stratify patients for a recurrence risk adapted postoperative treatment., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.

Objective: In this study, we evaluate the frequency of HER-2 and HER-3 expression in liver metastases from patients with colorectal cancer (CRLM). We analyzed the potential of HER-2 and HER-3 as therapeutic targets and evaluated their prognostic value., Patients and Methods: Overall 208 patients with CRLM were enrolled. HER-2 and HER-3 expression were determined in metastatic tissue of diagnostic punch biopsies (n = 29) or resection specimens (n = 179). The results of immunohistochemistry (IHC) scoring and In-situ-hybridization (ISH)-amplification were correlated with clinical parameters and for the 179 resected patients with cancer-specific (CSS) and overall survival (OS). The mean follow-up time was 56.7 months., Results: Positivity of HER-2 status (IHC score 2+/ISH+ and IHC 3+) was found in 8.2% of CRLM. High expression of HER-3 (IHC score 2+ and IHC 3+) was detected in 75.0% of liver metastases. CSS after liver surgery was determined and was independent from the HER-2 status (p = 0.963); however HER-3 was prognostic with a favorable course for patients showing an overexpression of HER-3 (p = 0.037)., Conclusions: HER-2 overexpression occurs in only 8% of patients with CRLM but with 75% of cases HER-3 is frequently overexpressed in CRLM. Therefore, HER-2 and particularly HER-3 could serve as novel targets to be addressed within multimodal treatment approaches.

Immunohistochemistry of trephine bone marrow biopsies plays a prominent role in diagnostic assessment of a broad spectrum of non-neoplastic and neoplastic hematologic and metastatic diseases. We tested the quality of immunohistochemical stainings in sections of methyl-methacrylate-embedded core biopsies prepared according to the so-called Hannover-method of cold polymerization using the novel biotin-free tyramide signal amplification system in comparison to the alkaline phosphatase-conjugated "EnVision" method. Examining a large panel of immunohistochemical markers, the amplification system proved to be a highly sensitive technique substantially superior to the EnVision-AP method in reliably detecting the antigenic determinants of the target cells and referred to the intensity of immunoprecipitations.

Several transporters belonging to the ABCA subfamily of ABC (ATP-binding cassette) proteins are involved in lipid trafficking. Human ABCA5 and its rat orthologue, rAbca5, represent recently identified subfamily members whose substrate spectrum remains to be defined. The elucidation of (sub)cellular rAbca5 distribution would be expected to provide a basis for optimization of functional analyses. In the present study, we applied in situ hybridization to examine rAbca5 mRNA distribution within sections of rat testis, a tissue expressing high levels of rAbca5 mRNA. We found rAbca5 mRNA to be predominantly expressed in interstitial Leydig cells, which are major sites of testosterone synthesis. To investigate rAbca5 subcellular localization, we constructed expression vectors yielding rAbca5 fused either to EGFP (enhanced green fluorescent protein) or to a peptide bearing the viral V5 epitope. During rAbca5 cDNA cloning, we discovered a splice variant sequence (rAbca5 V20+16), predicted to give rise to a truncated, half-size transporter, which was highly homologous with a human splice variant described by us previously. Quantitative RT (reverse transcription)-PCR demonstrated that the rAbca5 splice variant was expressed in numerous tissues (including testis, brain and lungs), its cDNA amounting to 2.6-11.2% of total rAbca5 cDNA. Transfection of individual rAbca5-EGFP, rAbca5 splice variant-EGFP or transporter-V5 expression plasmids along with organelle marker plasmids into HEK-293 cells (human embryonic kidney 293 cells) revealed that both rAbca5 and splice variant fusion proteins co-localized with marker protein for the Golgi apparatus. Expression of rAbca5 mRNA in Leydig cells, intracellular localization of rAbca5-EGFP/rAbca5-V5 and involvement of rAbca5-related proteins in lipid transport suggest that rAbca5 may participate in intracellular sterol/steroid trafficking.

Background: Maturation of dendritic cells (DCs) influences important DC functions such as production of cytokines. Recently, DCs were identified as a source of interleukin-16 (IL-16), a chemotactic factor for DCs themselves, CD4+ T cells, and eosinophils. There is evidence that DC-derived IL-16 may contribute to the pathogenesis of atopic dermatitis (AD)., Objective: To investigate the production of IL-16 during differentiation of monocytes into DCs in healthy individuals and patients with AD., Methods: IL-16 production was investigated by quantitative real-time RT-PCR, intracellular cytokine staining, immunoblotting, and ELISA., Results: DCs generated from peripheral monocytes by 5-day culture in the presence of IL-4 and granulocyte/macrophage colony-stimulating factor acquired the capability to synthesize, store, and secrete IL-16. Storage and release of IL-16 was further enhanced during final DC maturation induced by additional 3-day culture with tumor necrosis factor-alpha (TNF-alpha) and monocyte-conditioned medium. Maturation, as determined by up-regulation of CD83 and CD86 surface expression, and production of IL-16, but not production of IL-10 and IL-12p40 was impaired in day 8 DCs derived from AD patients compared to those from healthy donors. Stimulation of day 8 DCs from AD patients with TNF-alpha and IL-1beta enhanced the expression of CD83 and CD86 and restored the production of IL-16., Conclusions: Signals involved in the activation and maturation of DCs enhance their capacity to produce IL-16. Functional abnormalities present in patients with AD at the monocyte level may account for impaired maturation and IL-16 production of monocyte-derived DCs.

Objective: Fractalkine (CX3CL1) represents the sole member of the so-called CX3C chemokines. In rheumatoid arthritis (RA), functional studies suggest a role for this chemokine in monocyte chemotaxis and angiogenesis in the rheumatoid synovium. We analyzed the expression of fractalkine within different T cell subsets of the peripheral blood and expression of its receptor CX3CR1 within the rheumatoid synovium to further characterize its pathogenic role in RA., Methods: Peripheral blood mononuclear cells (PBMC) were isolated from 17 patients with RA and analyzed by flow cytometry in comparison to healthy blood donors. To identify the T helper cell cytokine profile of fractalkine-expressing cells, flow cytometric analysis of PBMC was performed after stimulation with PMA and ionomycin. Expression of fractalkine and its receptor was characterized in RA synovium by immunohistochemistry and laser capture microdissection microscopy., Results: Flow cytometric analysis of fractalkine-expressing T cell subsets revealed a low proportion of fractalkine-expressing CD4+ and CD8+ T cells in both RA patients and controls. In addition, fractalkine was predominantly expressed in CD4+ T cells with a Th1-type cytokine expression profile. In RA synovium, fractalkine was detected in synovial macrophages, dendritic cells, endothelial cells, and a small proportion of T cells. The fractalkine receptor CX3CR1 was found in synovial macrophages, dendritic cells, and T cells as well as in synovial fibroblasts. Fractalkine stimulation of cultured synovial fibroblasts resulted in a marked upregulation of matrix metalloproteinase-2 (MMP-2) production., Conclusion: The results suggest that fractalkine may represent a Th1-type chemokine. Upregulation of MMP-2 production in synovial fibroblasts upon fractalkine stimulation in vitro supports the hypothesis of a proinflammatory role of this chemokine in RA.

Peroxisome proliferator-activated receptor gamma is a member of the nuclear receptor superfamily involved in adipocyte differentiation and glucose homeostasis. There is evidence that peroxisome proliferator-activated receptor gamma may also act as a tumor suppressor. Here, we demonstrate expression of peroxisome proliferator-activated receptor gamma in benign melanocytic naevi, different variants of primary cutaneous melanomas, and melanoma metastases. Peroxisome proliferator-activated receptor gamma protein and peroxisome proliferator-activated receptor gamma1 mRNA were also detected in human melanoma cell lines. The peroxisome proliferator-activated receptor gamma specific agonists 15-deoxy-Delta12,14-prostaglandin J2, troglitazone, and rosiglitazone dose-dependently inhibited cell proliferation in four melanoma cell lines, whereas a specific agonist of peroxisome proliferator-activated receptor alpha had no such effect. At a concentration of 50 microM rosiglitazone, the most potent peroxisome proliferator-activated receptor gamma agonist tested suppressed cell growth by approximately 90%. Apoptosis could be induced in melanoma cell lines by incubation with tumor-necrosis-factor-related apoptosis-inducing ligand. In contrast, the growth inhibitory effect of peroxisome proliferator-activated receptor gamma activation was independent of apoptosis and seemed to occur primarily through induction of cell cycle arrest. Our data indicate that melanoma cell growth may be modulated through peroxisome proliferator-activated receptor gamma.