ABSTRACT
BACKGROUND: The need to unfold the underlying mechanisms of lung cancer aggressiveness, the deadliest cancer in the world, is of prime importance. Because Fas-associated death domain protein (FADD) is the key adaptor molecule transmitting the apoptotic signal delivered by death receptors, we studied the presence and correlation of intra- and extracellular FADD protein with development and aggressiveness of non-small cell lung cancer (NSCLC). METHODS: Fifty NSCLC patients were enrolled in this prospective study. Intracellular FADD was detected in patients' tissue by immunohistochemistry. Tumours and distant non-tumoural lung biopsies were cultured through trans-well membrane in order to analyse extracellular FADD. Correlation between different clinical/histological parameters with level/localisation of FADD protein has been investigated. RESULTS: Fas-associated death domain protein could be specifically downregulated in tumoural cells and FADD loss correlated with the presence of extracellular FADD. Indeed, human NSCLC released FADD protein, and tumoural samples released significantly more FADD than non-tumoural (NT) tissue (P=0.000003). The release of FADD by both tumoural and NT tissue increased significantly with the cancer stage, and was correlated with both early and late steps of the metastasis process. CONCLUSION: The release of FADD by human NSCLC could be a new marker of poor prognosis as it correlates positively with both tumour progression and aggressiveness.
Subject(s)
Carcinoma, Non-Small-Cell Lung/metabolism , Fas-Associated Death Domain Protein/metabolism , Lung Neoplasms/metabolism , Adult , Aged , Aged, 80 and over , Biomarkers, Tumor/analysis , Carcinoma, Non-Small-Cell Lung/pathology , Disease Progression , Extracellular Space/metabolism , Female , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Neoplasm Metastasis , Prognosis , Prospective StudiesABSTRACT
This study was undertaken to evaluate the possibility to obtain a molecular signature of rheumatoid arthritis (RA) comparatively osteoarthritis (OA), and to lay the bases to develop new diagnostic tools and identify new targets. Microarray technology was used for such an analysis. The gene expression profiles of synovial tissues from patients with confirmed RA, and patients with OA were established and compared. A set of 63 genes was selected, based, more specifically, on their overexpression or underexpression in RA samples compared to OA. Results for six of these genes have been verified by quantitative PCR using both samples identical to those used in the microarray experiments and entirely separate samples. Expression profile of the 48 known genes allowed the correct classification of additional RA and OA patients. Furthermore, the distinct expression of three of the selected genes was also studied by quantitative RT-PCR in cultured synovial cells. Detailed analysis of the expression profile of the selected genes provided evidence for dysregulated biological pathways, pointed out to chromosomal location and revealed novel genes potentially involved in RA. It is proposed that such an approach allows valuable diagnosis/prognostics tools in RA to be established and potential targets for combating the disease to be identified.
Subject(s)
Arthritis, Rheumatoid/genetics , Arthritis, Rheumatoid/physiopathology , Gene Expression , Oligonucleotide Array Sequence Analysis/methods , Osteoarthritis/genetics , RNA, Messenger/metabolism , Adult , Aged , Aged, 80 and over , Cathepsin L , Cathepsins/genetics , Cathepsins/metabolism , Cells, Cultured , Clusterin , Cysteine Endopeptidases , DEAD-box RNA Helicases , DNA Primers , Female , GTP-Binding Proteins/genetics , GTP-Binding Proteins/metabolism , Glycoproteins/genetics , Glycoproteins/metabolism , Humans , Lactoylglutathione Lyase/genetics , Lactoylglutathione Lyase/metabolism , Male , Membrane Proteins/genetics , Membrane Proteins/metabolism , Middle Aged , Molecular Chaperones/genetics , Molecular Chaperones/metabolism , Nucleic Acid Hybridization , Polymerase Chain Reaction , RNA Helicases/genetics , RNA Helicases/metabolism , Reverse Transcriptase Polymerase Chain Reaction , Synovial Fluid/metabolismABSTRACT
Constitutive Fas ligand (FasL) expression by specialized cells in the body participates in the immune privilege status of tissues containing these cells. This property has been used to prevent rejection of allogeneic grafts. Nevertheless, the mechanism responsible for such protection has not been fully elucidated. Unfortunately, grafting of FasL transgenic (TG) tissues has been unsuccessful. We have generated TG mice expressing FasL (soluble + membrane bound) on thyroid follicular cells (TFC), and used them to show that ectopic FasL expression prevents thyroid allograft rejection. FasL expression on TFC led to markedly decreased anti-allogeneic, cytotoxic, and helper T lymphocyte activities. The alloantibody response in TG thyroid recipients was either completely inhibited or switched toward a T2-Ab response. Surprisingly, the beneficial effect of FasL on TG thyroid grafts was abolished by host CD4(+) T cell depletion. Host CD8(+) T cell depletion improved nontransgenic (NTG), but not TG graft survival. Altogether, our results suggest that FasL-induced tolerance is concomitant with a move away from a T1 type response, and a CD4 T cell-mediated regulation of the allocytotoxic T cell response. These results were dependent upon the level of FasL expression on TFC, in that low expression of FasL led to a less marked effect compared with the effect observed with high expression of FasL. These results provide some insight into the role of FasL in regulating destructive alloimmune responses in the case of whole organ grafting, and they have important implications for the development of FasL-based immunotherapy in organ transplantation.
