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Abstract Background Malignancy after transplantation is a leading cause of death among kidney transplant recipients. However, donor-derived malignancies are rare. We report a case of a high grade papillary urothelial carcinoma arising in a transplanted kidney. Case presentation A 62-year-old female who received a kidney transplantation more than 30 years ago presented with urinary tract infection, acute renal failure, and hydronephrosis of the transplant kidney. Anterograde nephrostogram showed a large filling defect in the lower pole of the transplant kidney and in the proximal 3–4 cm of the ureter. A biopsy from the renal pelvic mass showed a high grade urothelial carcinoma. She underwent an anterior exenteration, resection of both transplant and native kidneys and bilateral pelvic lymph node dissection. Pathologic examination showed a high grade papillary urothelial carcinoma which appeared to arise in the pelvis of the graft kidney, involve the graft ureter and native urinary bladder. The tumor had metastasized to one left obturator lymph node but spared the two native kidneys and ureters. Short tandem repeat (STR) analysis confirmed the tumor to be of donor origin. Next-generation sequencing identified amplification of TERT and loss of CDKN2A/CDKN2B in the primary tumor. Conclusion While it is known that transplant recipients have an increased risk of urothelial carcinoma compared to the general population, the lack of the well-documented risk factors, such as older age at transplantation, BK polyomavirus infection, and prolonged post-transplantation history and dissemination of the tumor in this case shed light on the de novo tumorigenesis of the graft kidney within the host microenvironment. Amplification of Telomerase reverse transcriptase (TERT) and loss of cyclin dependent kinase inhibitor 2A/2B (CDKN2A/CDKN2B) detected in the tumor by next gene sequencing suggests that they may play an important role in this case.

Abstract Background Caspase-8 is a well-established initiator of apoptosis and suppressor of necroptosis, but maintains functions beyond cell death that involve suppression of receptor-interacting serine-threonine kinases (RIPKs). A genome-wide association study meta-analysis revealed an SNP associated with risk of rheumatoid arthritis (RA) development within the locus containing the gene encoding for caspase-8. Innate immune cells, like macrophages and dendritic cells, are gaining momentum as facilitators of autoimmune disease pathogenesis, and, in particular, RA. Therefore, we examined the involvement of caspase-8 within these antigen-presenting cell populations in the pathogenesis of an arthritis model that resembles the RA effector phase. Methods Cre LysM Casp8 flox/flox and Cre CD11c Casp8 flox/flox mice were bred via a cross between Casp8 flox/flox and Cre LysM or Cre CD11c mice. RIPK3 –/– Cre LysM Casp8 flox/flox and RIPK3 –/– Cre CD11c Casp8 flox/flox mice were generated to assess RIPK3 contribution. Mice were subjected to K/BxN serum-transfer-induced arthritis. Luminex-based assays were used to measure cytokines/chemokines. Histological analyses were utilized to examine joint damage. Mixed bone marrow chimeras were generated to assess synovial cell survival. Flow cytometric analysis was employed to characterize cellular distribution. For arthritis, differences between the groups were assessed using two-way analysis of variance (ANOVA) for repeated measurements. All other data were compared by the Mann-Whitney test. Results We show that intact caspase-8 signaling maintains opposing roles in lysozyme-M- and CD11c-expressing cells in the joint; namely, caspase-8 is crucial in CD11c-expressing cells to delay arthritis induction, while caspase-8 in lysozyme M-expressing cells hinders arthritis resolution. Caspase-8 is also implicated in the maintenance of synovial tissue-resident macrophages that can limit arthritis. Global loss of RIPK3 in both caspase-8 deletion constructs causes the response to arthritis to revert back to control levels via a mechanism potentially independent of cell death. Mixed bone marrow chimeric mice demonstrate that caspase-8 deficiency does not confer preferential expansion of synovial macrophage and dendritic cell populations, nor do caspase-8-deficient synovial populations succumb to RIPK3-mediated necroptotic death. Conclusions These data demonstrate that caspase-8 functions in synovial antigen-presenting cells to regulate the response to inflammatory stimuli by controlling RIPK3 action, and this delicate balance maintains homeostasis within the joint.

Abstract Background Rheumatoid arthritis (RA) is a common autoimmune disease characterized by chronic inflammation of the joints, leading to bone erosion and joint dysfunction. Despite the recent successes of disease-modifying anti-rheumatic drugs (DMARDs), there is still clinical need for understanding the development and molecular etiology of RA. Wnts are developmental morphogens whose roles in adult pathology are poorly characterized. Wnt5a is a member of the non-canonical family of Wnts that modulates a wide range of cell processes, including differentiation, migration, and inflammation. Wnt5a has been implicated as a possible contributor to arthritis and it is upregulated in synovial fibroblasts from RA patients. Methods We investigated the role of endogenous Wnt5a in RA. Tamoxifen-inducible, Wnt5a knockout (Wnt5a cKO) mice and littermate controls were monitored for arthritis development and joint pathology using the K/BxN serum transfer-induced arthritis (STIA) model. To explore a role of Wnt5a in osteoclast fusion, bone marrow-derived monocytes (BMDMs) were differentiated in vitro. Results Wnt5a cKO mice were resistant to arthritis development compared to control littermates as assessed by ankle thickness and histologic measurements. Some parameters of inflammation were reduced in the Wnt5a cKO mice, including the extent of polymononuclear cell infiltration and extra-articular inflammation. Wnt5a cKO mice also exhibited less cartilage destruction and a reduction in osteoclast activity with concomitant reduction in tartrate-resistant acid phosph atase (TRAP), cathepsin K (CTSK), macrophage colony-stimulating factor (MCSF), matrix metalloproteinase (MMP)2 and MMP9 in the arthritic joints. Treatment of BMDMs with Wnt5a enhanced osteoclast fusion and increased the expression of dendrocyte-expressed seven transmembrane protein (DCSTAMP) and MMP9, that are necessary for osteoclast formation and activity. Conclusions These data suggest that Wnt5a modulates the development of arthritis by promoting inflammation and osteoclast fusion, and provide the first mouse genetic evidence of a role for endogenous Wnt5a in autoimmune disease.

Different subsets and/or polarized phenotypes of monocytes and macrophages may play distinct roles during the development and resolution of inflammation. Here, we demonstrate in a murine model of rheumatoid arthritis that nonclassical Ly6C− monocytes are required for the initiation and progression of sterile joint inflammation. Moreover, nonclassical Ly6C− monocytes differentiate into inflammatory macrophages (M1), which drive disease pathogenesis and display plasticity during the resolution phase. During the development of arthritis, these cells polarize toward an alternatively activated phenotype (M2), promoting the resolution of joint inflammation. The influx of Ly6C− monocytes and their subsequent classical and then alternative activation occurs without changes in synovial tissue-resident macrophages, which express markers of M2 polarization throughout the course of the arthritis and attenuate joint inflammation during the initiation phase. These data suggest that circulating Ly6C− monocytes recruited to the joint upon injury orchestrate the development and resolution of autoimmune joint inflammation.

The free radical nitric oxide (NO●) is known to play a dual role in human physiology and pathophysiology. At low levels, NO● can protect cells; however, at higher levels, NO● is a known cytotoxin, having been implicated in tumor angiogenesis and progression. While the majority of research devoted to understanding the role of NO● in cancer has to date been tissue-specific, we herein review underlying commonalities of NO● which may well exist among tumors arising from a variety of different sites. We also discuss the role of NO● in human physiology and pathophysiology, including the very important relationship between NO● and the glutathione-transferases, a class of protective enzymes involved in cellular protection. The emerging role of NO● in three main areas of epigenetics—DNA methylation, microRNAs, and histone modifications—is then discussed. Finally, we describe the recent development of a model cell line system in which human tumor cell lines were adapted to high NO● (HNO) levels. We anticipate that these HNO cell lines will serve as a useful tool in the ongoing efforts to better understand the role of NO● in cancer.

To identify disease‐specific gene expression profiles in patients with rheumatoid arthritis (RA), using complementary DNA (cDNA) microarray analyses on lymphoblastoid B cell lines (LCLs) derived from RA‐discordant monozygotic (MZ) twins.The cDNA was prepared from LCLs derived from the peripheral blood of 11 pairs of RA‐discordant MZ twins. The RA twin cDNA was labeled with cy5 fluorescent dye, and the cDNA of the healthy co‐twin was labeled with cy3. To determine relative expression profiles, cDNA from each twin pair was combined and hybridized on 20,000‐element microarray chips. Immunohistochemistry and real‐time polymerase chain reaction were used to detect the expression of selected gene products in synovial tissue from patients with RA compared with patients with osteoarthritis and normal healthy controls.In RA twin LCLs compared with healthy co‐twin LCLs, 1,163 transcripts were significantly differentially expressed. Of these, 747 were overexpressed and 416 were underexpressed. Gene ontology analysis revealed many genes known to play a role in apoptosis, angiogenesis, proteolysis, and signaling. The 3 most significantly overexpressed genes were laeverin (a novel enzyme with sequence homology to CD13), 11β‐hydroxysteroid dehydrogenase type 2 (a steroid pathway enzyme), and cysteine‐rich, angiogenic inducer 61 (a known angiogenic factor). The products of these genes, heretofore uncharacterized in RA, were all abundantly expressed in RA synovial tissues.Microarray cDNA analysis of peripheral blood–derived LCLs from well‐controlled patient populations is a useful tool to detect RA‐relevant genes and could help in identifying novel therapeutic targets. [ABSTRACT FROM AUTHOR]

CC chemokines and their receptors play a fundamental role in trafficking and activation of leukocytes at sites of inflammation, contributing to joint damage in rheumatoid arthritis. Met‐RANTES, an amino‐terminal–modified methionylated form of RANTES (CCL5), antagonizes the binding of the chemokines RANTES and macrophage inflammatory protein 1α (MIP‐1α; CCL3) to their receptors CCR1 and CCR5, respectively. The aim of this study was to investigate whether Met‐RANTES could ameliorate adjuvant‐induced arthritis (AIA) in the rat.Using immunohistochemistry, enzyme‐linked immunosorbent assay, real‐time reverse transcription–polymerase chain reaction, Western blot analysis, adoptive transfer, and chemotaxis, we defined joint inflammation, bony destruction, neutrophil and macrophage migration, Met‐RANTES binding affinity to rat receptors, proinflammatory cytokine and bone marker levels, CCR1 and CCR5 expression and activation, and macrophage homing into joints with AIA.Administration of Met‐RANTES as a preventative reduced the severity of joint inflammation. Administration of Met‐RANTES to ankles with AIA showed decreases in inflammation, radiographic soft tissue swelling, and bone erosion. Met‐RANTES significantly reduced the number of neutrophils and macrophages at the peak of arthritis compared with saline‐injected controls. Competitive chemotaxis in peripheral blood mononuclear cells demonstrated that Met‐RANTES inhibited MIP‐1α and MIP‐1β at 50% inhibition concentrations of 5 nM and 2 nM, respectively. Furthermore, levels of tumor necrosis factor α, interleukin‐1β, macrophage colony‐stimulating factor, and RANKL were decreased in joints with AIA in the Met‐RANTES group compared with the control group. Interestingly, the expression and activation of CCR1 and CCR5 in the joint were down‐regulated in the Met‐RANTES group compared with the control group. Functionally, Met‐RANTES administration decreased adoptively transferred peritoneal macrophage homing into the joint.The data suggest that the targeting of Th1‐associated chemokine receptors reduce joint inflammation, bone destruction, and cell recruitment into joints with AIA. [ABSTRACT FROM AUTHOR]

This study was undertaken to characterize the role of CC chemokines and their receptors in rat adjuvant-induced arthritis (AIA), a model for rheumatoid arthritis (RA). Furthermore, we investigated the signaling pathways associated with CC receptors as well as the cell type distribution of the receptors. Using TaqMan real-time reverse transcription–polymerase chain reaction, Western blot analysis, and immunohistochemistry, we defined chemokine and chemokine receptor messenger RNA (mRNA) expression, CC chemokine receptor (CCR) protein activation during the disease course, CCR-associated signaling pathways, and immunopositive CCR5, phosphorylated signal transducer and activator of transcription 1 (p-STAT-1), and p-STAT-3 cells in rat AIA versus control joints. We showed significant up-regulation of CCR1, CCR2, CCR5, and macrophage inflammatory protein 1β/CCL4 mRNA in AIA on post–adjuvant injection day 18, coincident with peak inflammation. Additionally, increases in tyrosine phosphorylation of CCR1 (days 14, 18, 21, and 24), CCR2 (days 14 and 18), and CCR5 (days 14, 18, and 21) were detected in AIA rats compared with control (nonarthritic) rats. JAK-1, STAT-1, and STAT-3 were associated with CCR1 and were highly tyrosine phosphorylated on days 14 and 18. Moreover, CCR2 was associated with JAK-2, STAT-1, and STAT-3 on day 18. The association of STAT-1 and STAT-3 with CCR5 on days 18 and 21 correlated with JAK-1 phosphorylation and binding on day 18. However, the activation of JNK was not associated with CCR5 activation in rat AIA. Immunohistochemical analysis demonstrated that the expression of CCR5, p-STAT-1, and p-STAT-3 was detected on synovial lining cells, macrophages, and endothelial cells in arthritic rat ankles on post–adjuvant injection day 18. While the majority of the CCR5 and p-STAT-1 immunostaining was on synovial lining cells and macrophages, p-STAT-3 was predominantly expressed on endothelial cells. CCR1, CCR2, and CCR5 mRNA expression and tyrosine phosphorylation increased with peak inflammation in the AIA model. CCR1, CCR2, and CCR5 tyrosine phosphorylation are associated with the JAK/STAT-1/STAT-3 pathway at different stages of rat AIA, as well as with macrophage and endothelial cell infiltration. However, their signaling activation overlaps with peak inflammation. Up-regulation and activation of CCRs may play a role in macrophage and endothelial cell infiltration in rat AIA joints in addition to activating the associated signaling pathways. The downstream intermediate signaling proteins associated with CC receptors may be used as potential tools to control inflammation in RA. [ABSTRACT FROM AUTHOR]

SUMMARY: PURPOSE Thyroid hormone is essential for normal development, growth, and function of the majority of tissues. Among the many clinical signs associated with hypothyroidism, alterations in the voice may occur even in cases of mild thyroid failure, suggesting that the larynx is a target tissue for thyroid hormone. The objective of our study is to further understand the effects of thyroid hormone on the larynx by first identifying the presence and locations of its receptors.METHODS Two human cadaveric larynges (one male and one female) were harvested, formalin-fixed, and paraffin-embedded. Sections were immunostained with antibodies reactive with the two identified thyroid hormone receptors, TR-α and TR-β. The slides were examined under light microscopy.RESULTS Both male and female specimens revealed consistent patterns of staining for thyroid hormone receptors. The staining pattern for TR-α included the fibrous connective tissue of the lamina propria, the cartilage, and the glandular elements. The staining pattern for TR-β included the fibrous connective tissue of the lamina propria only. No receptors were identified in the respiratory mucosa or muscle.CONCLUSIONS Thyroid hormone receptors are present in both the male and the female human larynx. These findings imply a role for thyroid hormone within the human larynx, through both TR-α and TR-β. [ABSTRACT FROM AUTHOR]

SUMMARY: OBJECTIVES/HYPOTHESIS Diagnosis and treatment of gastroesophageal and laryngopharyngeal reflux disease has significantly increased over recent years. The larynx is highly sensitive to the effects of LPRD and is similarly responsive to proton pump inhibitor pharmacotherapy. The hypothesis of the study was that proton pump activity exists in the human larynx and plays a functional role in normal and/or pathological laryngeal tissue.STUDY DESIGN Pathological investigation.METHODS Two fresh human cadaveric larynges (one male and one female larynx) were obtained as part of an exempt protocol from the Human Subjects Committee and were formalin fixed and paraffin embedded. Banked human stomach tissue was also obtained for use as comparative positive and negative control specimens. Sections were immunostained with monoclonal antibodies reactive with both alpha and beta subunits of the H+/K+-ATPase (proton) pump. Specimens were reviewed for staining pattern and intensity.RESULTS Stomach parietal cells (known to produce gastric acid) exhibited strongly positive staining for both the alpha and beta subunits of the proton pump. There was no staining in stomach cells that were not morphologically consistent with the parietal cell. In the human larynx there were strong focal and identical staining patterns in the serous cells and ducts of the minor seromucinous glands by both alpha and beta monoclonals to the proton pump. There was variable staining in the laryngeal epithelium that was thought to be consistent with artifact staining resulting from tissue processing.CONCLUSION The H+/K+-ATPase (proton) pump is present in serous cells and ducts of submucosal glands in the human larynx. Proton pump inhibitor pharmacotherapy may have a site of action in seromucinous glands of the human larynx, with possible relevance for patients treated for chronic laryngitis with or without laryngopharyngeal reflux disease. [ABSTRACT FROM AUTHOR]

Objective. SSc is characterized by microvascular abnormalities and leucocyte infiltration. Previous studies have suggested a proadhesive phenotype in SSc skin, but the functional consequences of this phenotype are not fully understood. Molecules known to mediate leucocyte adhesion include those present at intracellular junctions, such as junctional adhesion molecule-B (JAM-B), JAM-C and CD99, as well as intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1). The aim of this study was to examine adhesive interactions in SSc skin. Methods. The expression of JAM-B, JAM-C, CD99, ICAM-1 and VCAM-1 in SSc skin was determined by immunohistology and cell surface ELISA. Myeloid U937 cell–SSc dermal fibroblast adhesion assays or in situ adhesion assays to SSc skin were performed. Results. JAM-C and CD99 expression on endothelial cells (ECs) in SSc skin was decreased compared with expression on normal ECs. CD99 was overexpressed on mononuclear cells in SSc skin and on SSc dermal fibroblasts. Neutralizing ICAM-1 inhibited the binding of U937 cells to SSc dermal fibroblasts. In addition, blocking both ICAM-1 and VCAM-1 inhibited U937 cell adhesion to either proximal (less involved) or distal (more involved) SSc skin. Conclusions. These studies show that JAM-C and CD99 are aberrantly expressed in SSc skin. However, these adhesion molecules do not mediate myeloid cell–SSc skin adhesion. In contrast, we demonstrate an important role for ICAM-1 and VCAM-1 in the retention of myeloid cells in SSc skin, suggesting that targeting these molecules may be useful SSc therapies. [ABSTRACT FROM AUTHOR]

Chemokine receptors mediate leukocyte migration into inflamed rheumatoid arthritis (RA) synovial tissue (ST). Knowledge of their distribution is crucial for understanding the evolution of the inflammatory process. In this study, we used rat adjuvant‐induced arthritis (AIA), a model for RA, to define the temporospatial expression of chemokine receptors.ST from rats with AIA was immunostained, the percentage of cells expressing each receptor was determined, and findings were correlated with levels of inflammation. Chemokine receptor expression was evaluated on rat macrophages in vitro.CCR1, a receptor for macrophage inflammatory protein 1α (MIP‐1α)/CCL3 and RANTES/CCL5, exhibited high constitutive expression on macrophages in AIA. CCR5, binding MIP‐1α/CCL3 and RANTES/CCL5, was up‐regulated on ST macrophages during the course of AIA, correlating with macrophage expression of CCR2, a receptor for monocyte chemoattractant protein 1/CCL2. Endothelial cell (EC) CCR2 was down‐regulated as arthritis progressed, inversely correlating with inflammation. CCR3, another RANTES/CCL5 receptor, was constitutively high on macrophages in vivo and in vitro, with down‐regulation during AIA. CXCR4, a receptor for stromal cell–derived factor 1/CXCL12), was prominently up‐regulated on ECs, preceding the peak of inflammation.These findings show that 1) constitutive expression of CCR1 on macrophages remains high during AIA; 2) CCR2 and CCR3 may play a role in initial recruitment of leukocytes to ST in AIA; 3) macrophage expression of CCR2 and CCR5 may be important for sustaining inflammatory changes; and 4) EC CXCR4 may be a harbinger of inflammatory changes. Our results may help guide chemokine receptor blockade–targeting treatment strategies in inflammatory arthritis. [ABSTRACT FROM AUTHOR]