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61.
Francesca Khani Sara E Wobker Jessica L Hicks Brian D Robinson Christopher E Barbieri Angelo M De Marzo Jonathan I Epstein Colin C Pritchard Tamara L Lotan 《The Journal of pathology》2019,249(1):79-89
Intraductal carcinoma of the prostate (IDC-P) most often appears associated with high-grade invasive prostate carcinoma (PCa), where it is believed to represent retrograde spread. However, IDC-P rarely occurs as an isolated finding at radical prostatectomy or with concurrent low-grade (Grade Group 1) invasive carcinoma. We hypothesized that isolated IDC-P (iIDC-P) in these unusual cases may represent a distinct in situ lesion and molecularly profiled 15 cases. iIDC-P was characterized by copy number alteration (CNA) profiling and targeted next generation sequencing in cases with sufficient tissue (n = 7). Immunohistochemistry for PTEN and ERG was performed on the total cohort (n = 15), where areas of iIDC-P and associated invasive disease were evaluated separately (n = 9). By copy number profiling, iIDC-P alterations were similar to those previously described in high-grade invasive PCa (PTEN, RB1, and CHD1 loss; MYC gain). However, in four cases, targeted sequencing revealed a striking number of activating oncogenic driver mutations in MAPK and PI3K pathway genes, which are extraordinarily rare in conventional PCa. In addition, pathogenic mutations in DNA repair genes were found in two cases of iIDC-P (BRCA2, CHEK2, CDK12) and other known PCa-associated mutations (FOXA1, SPOP) in two cases. Overall, ERG was expressed in 7% (1/15) of the iIDC-P lesions and PTEN was lost in 53% (8/15). Discordance for ERG or PTEN status between IDC-P and the low-grade PCa was observed in five of nine cases, with intact PTEN in the invasive tumor and PTEN loss in IDC-P in four. Despite a CNA profile similar to conventional PCa, iIDC-P is enriched with potentially targetable oncogenic driver mutations in MAPK/PI3K genes. Based on PTEN and ERG status, iIDC-P is not likely a precursor to the associated low-grade invasive PCa, but represents a molecularly unique in situ tumor of unclear clinical significance. © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. 相似文献
62.
Chia-Cheng Yu Chien-Feng Li I-Hsuan Chen Ming-Tsung Lai Zi-Jun Lin Praveen K Korla Chee-Yin Chai Grace Ko Chih-Mei Chen Tritium Hwang Shan-Chih Lee Jim J-C Sheu 《The Journal of pathology》2019,248(4):476-487
The objective of this study was to characterize the oncogenic actions of a recently identified cancer-associated gene YWHAZ (also named as 14-3-3 ζ/δ) in urothelial carcinomas of the urinary bladder (UCUB). A genome-wide study revealed YWHAZ to be involved in the amplicon at 8q22.3, and its genetic amplification was detected predominantly in muscle-invasive bladder cancer (MIBC). Immunohistochemical staining confirmed the association of YWHAZ overexpression with higher tumor stages, lymph node/vascular invasion, and mitotic activity. Univariate and multivariate analyses further indicated the prognostic potential of YWHAZ for more aggressive cancer types. Both gene set enrichment analysis and STRING network studies suggested involvement of YWHAZ in regulating caspase-mediated apoptosis. Ectopic expression of YWHAZ in bladder cells with low endogenous YWHAZ levels boosted cell resistance to doxorubicin and cisplatin, as well as to ionizing radiation. Conversely, YWHAZ-knockdown using specific shRNA in cells with high endogenous YWHAZ levels diminished survival activity, suppressing cell growth and increasing cell death. Our findings confirm the essential role played by YWHAZ in sustaining cell proliferation during chemo/radiotherapy. Treatments based on anti-YWHAZ strategies may thus be beneficial for UCUB patients overexpressing YWHAZ. © 2019 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献
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Shauna M. Quinn Mathilde Raverdeau Aoife M. McGinley Kingston H.G. Mills 《European journal of immunology》2019,49(8):1291-1294
Infection with helminths can protect against the development of autoimmune diseases and this has been associated with induction of anti‐inflammatory innate immune responses and Tregs. Here, we demonstrate that helminth‐derived products can directly target T cells, especially IL‐17‐secreting γδ T cells that play a key pathogenic role in CNS autoimmune disease. 相似文献
65.
Gerhild Wildner 《Immunobiology》2019,224(1):172-176
In contrast to rats, mouse models are nowadays generally used for the investigation of immune responses and immune-mediated diseases, there are many different strains and mouse-specific tools available, and it is easy to generate transgenic and constitutive or inducible knockout mice for any gene. Many immune markers and mechanisms have been detected in mice and have been introduced as gold standard in immunology, however, some turned out to be not unconditionally transferable to the human immune system.Rats have been used more frequently in former days but are mostly outstripped by mice due to the fact that fewer strains are available, they need more space than mice, are more expensive to maintain and breed, and it is extremely difficult to generate transgenic or ko-rats. Consequently, the choice of rat-specific diagnostic tools like antibodies is quite poor and most researchers have switched to mouse models for the investigation of immune mechanisms, while rats are still widely used for toxicology by the pharmaceutical industry. However, it should be taken into consideration that there are some immunological similarities between rats and humans that are not presented in mice. Some of them like MHC class II and Foxp3 expression by activated effector T cells we have detected during our research on the immune response of rat models of experimental autoimmune uveitis. 相似文献
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68.
Anna Greenshields Robert A. Bray Howard M. Gebel Robert S. Liwski 《Human immunology》2019,80(7):468-477
A major limitation of the single antigen bead (SAB) assay is the so called prozone effect, whereby the detection of high titer complement fixing HLA antibodies is compromised due to complement split product (from C3 and C4 components) deposition and interference with the reporter anti-IgG-PE antibody binding. Strategies to minimize prozone include serum titration or treatment with heat, dithiotreitol (DTT), or ethylenediaminetetraacetic acid (EDTA). While effective, these treatments may compromise HLA antibody binding and detection. Here we describe the Dual Antibody Rapid Test (DART), a modified version of the rapid optimized SAB (ROB) protocol, in which we use an IgG-PE/C3d-PE antibody cocktail to simultaneously detect bead bound IgG and C3d, which allows for detection of HLA antibodies independent of the prozone effect. Twenty prozone positive sera (10 class I and 10 class II), identified by titration, were tested by the ROB protocol, with or without EDTA pre-treatment, using three reporter antibody cocktails: (1) IgG-PE, (2) C3d-PE, or (3) IgG-PE/C3d-PE (DART). Mean fluorescence intensity (MFI) values were then compared. IgG negative (n = 735) vs IgG positive (n = 1185) reactions were identified using a 1000 MFI IgG EDTA cutoff. IgG positive reactions were classified based on ΔMFI (IgG EDTA – IgG) as follows: (1) prozone negative (ΔMFI < 3000; n = 737), (2) slight prozone (ΔMFI 3001–5000; n = 49), (3) moderate prozone (ΔMFI 5001–10,000; n = 93), and (4) marked prozone (ΔMFI > 10,001; n = 306). No C3d deposition was present on IgG negative beads, and the majority of prozone positive specificities (438/448; 98%) fixed complement and were detected with the C3d-PE reporter. Interestingly, C3d-PE MFI was directly proportional to the degree of prozone (mean C3d-PE MFI = 4419.5 ± 1606.3 for slight, 5991.0 ± 2302.7 for moderate, and 12,417.4 ± 2969.9 for marked prozone specificities). Interestingly, EDTA treatment was found to have a negative impact on MFI of up to 15% of prozone negative specificities. Importantly, the DART protocol detected all prozone positive specificities while MFI for prozone negative specificities correlated well with those seen with the IgG-PE reporter alone (R2 = 0.97). In conclusion, the DART protocol accurately detects HLA antibodies independent of the prozone effect. Implementation of DART is an easy way to overcome the prozone effect without compromising HLA antibody detection. 相似文献
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70.
Amanda Szczepanik Carlo J. Iasella John F. McDyer Christopher R. Ensor 《Human immunology》2019,80(3):184-190
IntroductionThe number of solid organ transplants completed annually continues to trend upwards each year. Despite this, maintenance immunosuppression available on the market has remained relatively stagnant. Standard triple immunosuppression, composed typically of tacrolimus, mycophenolate, and steroids, lead to many side effects that limit the use of these medications. Tacrolimus, specifically, causes nephrotoxicity that can lead to renal dysfunction requiring a kidney transplant down the road. Alternative therapies for the management of immunosuppression need to be identified to try to mitigate these adverse effects.BodyCytokines are responsible for facilitating T cell differentiation and lead to the activation of inflammatory mediators that can contribute to graft damage and ultimately rejection. IL-4, IL-6, IL-12/23, and IL-15 are attractive targets for medications to try to ameliorate graft rejection. Various cytokine-targeted medications are currently available on the market for the treatment of inflammatory and autoimmune conditions such as rheumatoid arthritis, psoriatic arthritis, Crohn’s, and multiple sclerosis.ConclusionThis article reviews cytokine involvement in alloimmunity and the potential role cytokine-targeted therapy may play in prevention of allograft rejection in solid organ transplant recipients. 相似文献