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Müller-Hermelink N Braumüller H Pichler B Wieder T Mailhammer R Schaak K Ghoreschi K Yazdi A Haubner R Sander CA Mocikat R Schwaiger M Förster I Huss R Weber WA Kneilling M Röcken M 《Cancer cell》2008,13(6):507-518
Immune responses may arrest tumor growth by inducing tumor dormancy. The mechanisms leading to either tumor dormancy or promotion of multistage carcinogenesis by adaptive immunity are poorly characterized. Analyzing T antigen (Tag)-induced multistage carcinogenesis in pancreatic islets, we show that Tag-specific CD4+ T cells home selectively into the tumor microenvironment around the islets, where they either arrest or promote transition of dysplastic islets into islet carcinomas. Through combined TNFR1 signaling and IFN-gamma signaling, Tag-specific CD4+ T cells induce antiangiogenic chemokines and prevent alpha(v)beta(3) integrin expression, tumor angiogenesis, tumor cell proliferation, and multistage carcinogenesis, without destroying Tag-expressing islet cells. In the absence of either TNFR1 signaling or IFN-gamma signaling, the same T cells paradoxically promote angiogenesis and multistage carcinogenesis. Thus, tumor-specific T cells can directly survey multistage carcinogenesis through cytokine signaling. 相似文献
74.
Yazdi AS Morstedt K Puchta U Ghoreschi K Flaig MJ Rocken M Sander CA 《The Journal of investigative dermatology》2006,126(2):393-398
It is established that primary malignant melanomas (pMM) can be infiltrated by T-cell populations with predominantly one T-cell clone. As pMM generally express multiple tumor-associated antigens (TAA), here we used laser-capture microdissection (LCM) to isolate different tumor-infiltrating lymphocyte (TIL) clusters in order to determine whether pMM are infiltrated only by one single clone or whether the TAA may attract various T-cell populations. As T-cell receptor (TCR) clonality is a useful tool for the demonstration of specific T-cell clones, we analyzed 56 pMM, three cutaneous melanoma metastases, and 15 pairs of pMM with a sentinel lymph node (SLN) for clonal rearrangements of the (TCR) gamma chain gene. We detected the clonality of TCR gamma chain gene in 25 of 56 pMM, and in 10 of 17 SLN studied. In four of the 15 pairs of primary tumor and SLN, we found clonal TCR gamma in both the melanoma and the SLN, with two pairs harboring the identical clone. As we detected different clones in pMM and the corresponding SLN, we subsequently performed LCM in 21 malignant melanomas with multiple lymphocytic clusters for the presence of focal clonal T cells in different regions of the melanoma. In seven melanomas, both clusters of TILs showed the same rearranged TCR gamma chain gene and in five of the seven biopsies the clonal rearrangement occurred in different variable (V) regions of the TCR gamma chain gene. These tumors showed infiltration by more than one clone. In 10 biopsies TCR clonality was restricted to one cluster, while the second microdissected sample of the infiltrate was polyclonal. In conclusion, within one primary malignant melanoma several T-cell clones with different rearrangements may occur. The balance between these clones may decide on the progress of melanoma. 相似文献
75.
Rehan Ul Haq Prashant Modi IK Dhammi Anil K Jain Puneet Mishra 《Indian Journal of Orthopaedics》2013,47(3):302-306
Conjoint bicondylar Hoffa fracture is an extremely rare injury. Only one case has been reported previously in the pediatric age group. We describe this injury in a 17-year-old male who presented following a fall with direct impact on his semiflexed right knee. Plain radiographs were inadequate to define the exact pattern of injury. Computed tomographic (CT) scans demonstrated the coronal fracture involving both the femoral condyles which were joined by a bridge of intact bone. The patient was treated with open reduction and internal fixation using swashbuckler (modified anterior) approach. Union occurred within 3 months and at final followup (at 18 months) the patient had a good clinical outcome. The possible mechanism of injury is discussed. 相似文献
76.
Fatemeh Yazdi Shahram Shoeibi Mohammad Hossein Yazdi Akram Eidi 《Daru : journal of Faculty of Pharmacy, Tehran University of Medical Sciences》2021,29(1):159
BackgroundPolychlorinated biphenyls (PCBs) are a group of synthetic organic chlorine compounds known as an organic pollutant in food sources, which play important roles in malignancies. The present study aimed to investigate the direct effects of prevalent PCBs in food in hormone-responsive and non-responsive cell lines.MethodsIn the current study, MCF-7, LNCap, and MDA-MB231 cell lines were treated with serial concentrations (0.001–100 μM) of PCBs for 48 h and cell viability assessment was performed using MTT assay. The best concentration then applied and the expression level of PON1 was evaluated using real-time PCR. Besides, molecular docking was performed to determine the binding mechanism and predicted binding energies of PBCs compounds to the AhR receptor.ResultsUnlike MCF-7 and LNCap cells, the viability of MDA-MB231 cells did not significantly change by different concentrations of PCBs. Meanwhile, quantitative gene expression analysis showed that the PON1 was significantly more expressed in MCF-7 and LNCap lines treated with PCB28 and PCB101. However, the expression level of this gene in other groups and also MDA-MB231cells did not demonstrate any significantly change. Also, the results of molecular docking showed that PBCs had steric interaction with AhR receptor.ConclusionsCurrent results showed that despite of hormone non-responsive cells the PCBs have a significant positive effect on hormone-responsive cell. Therefore, and regarding to the existence of PCBs contamination in food there should be serious concern about their impact on the prevalence of different malignancies which certainly should result in a standard limit for this material.Graphical abstract Open in a separate windowThis study aimed to investigate the direct effects of prevalent PCBs in food in hormone-responsive and non-responsive cell lines. Cell lines were treated with serial concentrations of PCBs and cell viability assessment was performed using MTT assay. The expression level of PON1 was evaluated using real-time PCR. Molecular docking was performed to determine the binding mechanism and predicted binding energies of PBCs compounds to the AhR receptor. PCBs contamination in food there should be serious concern about their impact on the prevalence of different malignancies which certainly should result in a standard limit for this material. 相似文献
77.
Hossein M. Yazdi 《Diagnostic cytopathology》1986,2(4):326-329
The clinical, cytopathologic, and immunohistochemical features of three cases of extramedullary hemopoiesis are presented. Differentiation of megakaryocytes from malignant cells can be difficult in cytologic material; we believe familiarity with cytologic features of megakaryocytes, along with factor VIII-related antigen immunoreactivity, is helpful in providing an accurate diagnosis. Diagn Cytopathol 1986;2:326-329. 相似文献
78.
Glenn Liu Hope S Rugo George Wilding Teresa M McShane Jeffrey L Evelhoch Chaan Ng Edward Jackson Frederick Kelcz Benjamin M Yeh Fred T Lee Chusilp Charnsangavej John W Park Edward A Ashton Heidi M Steinfeldt Yazdi K Pithavala Steven D Reich Roy S Herbst 《Journal of clinical oncology》2005,23(24):5464-5473
PURPOSE: Identifying suitable markers of biologic activity is important when assessing novel compounds such as angiogenesis inhibitors to optimize the dose and schedule of therapy. Here we present the pharmacodynamic response to acute dosing of AG-013736 measured by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). PATIENTS AND METHODS: Thirty-six patients with advanced solid tumors were treated with various doses of AG-013736. In addition to standard measures of objective disease response and pharmacokinetic analysis, DCE-MRI scans were acquired at baseline and repeated at cycle 1--day 2 after the scheduled morning dose of the AG-013736 in 26 patients. Indicators of a vascular response, such as the volume transfer constant (K(trans)) and initial area under the curve (IAUC), were calculated to assess the effect of treatment on tumor vascular function. RESULTS: Evaluable vascular response data were obtained in 17 (65%) of 26 patients. A linear correlation was found in which the percentage change from baseline to day 2 in K(trans) and IAUC was inversely proportional to AG-013736 exposure. Using a conservative a priori assumption that a > or = 50% decrease in K(trans) was indicative of an objective vascular response, a 50% decrease in K(trans) was achieved and corresponded to a plasma AUC(0-24) of > 200 ng . h/mL. CONCLUSION: A sufficient decrease in tumor vascular parameters was observed at a dose chosen for additional phase II testing by conventional toxicity criteria. In addition, the day 2 vascular response measured using DCE-MRI seems to be a useful indicator of drug pharmacology, and additional research is needed to determine if it is a suitable marker for predicting clinical activity. 相似文献
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