393 research outputs found
Serum profiling reveals distinctive proteomic markers in the serum from chronic myeloid leukaemia patients
No full textWe have shown that proteomic profiling of sera from chronic myeloid leukaemia patients at presentation identifies five serum markers whose expression profile is significantly different from that seen in normal controls, non-malignant neutrophilia and in CML patients in HR following treatment with Gleevec. Of particular interest is the persistence of three of the five biomarkers following successful induction of HR, suggesting that those changes are disease specific. We have demonstrated that serum profiling can robustly identify disease groups and disease state in patients with CML compared with non-malignant and normal controls. In addition our data suggest that serum profiling of other haematological malignancies may provide new biomarkers for disease state and stag
Role of 4-1BB:4-1BBL in cancer immunotherapy
No full textThe activation of T cells plays a central role in antitumor immunity. In order to activate naïve T cells, two key signals are required. Signal one is provided through the T-cell receptor (TCR) while signal two is that of costimulation. The CD28:B7 molecules are one of the best-studied costimulatory pathways, thought to be the main mechanism through which primary T-cell stimulation occurs. However, a number of molecules have been identified which serve to amplify and diversify the T-cell response, following initial T-cell activation. These include the more recently described 4-1BB:4-1BB ligand (4-1BBL) molecules. 4-1BB:4-1BBL are a member of the TNFR:TNF ligand family, which are expressed on T cells and antigen-presenting cells (APCs), respectively. Therapies utilizing the 4-1BB:4-1BBL signaling pathway have been shown to have antitumor effects in a number of model systems. In this paper, we focus on the 4-1BB:4-1BBL costimulatory molecules. In particular, we will describe the structure and function of the 4-1BB molecule, its receptor and how 4-1BB:4-1BBL costimulation has and may be used for the immunotherapy of cance
The tumour antigens RAGE-1 and MGEA6 are expressed more frequently in the less lineage restricted subgroups of presentation acute myeloid leukaemia
No full textWe have analysed the frequency of present calls for RAGE-1 and MGEA6 in patients based on FAB subclass. MGEA6 and RAGE-1 present calls were significantly higher in the M0/M1/M2 versus the M3/M4/M5/M6/M7 groups for both RAGE-1 (p<0.0001) and MGEA6 (p<0.0001). However dividing patients into three WHO subgroups as follows (i) ‘recurrent’ representing acute myeloid leukaemia with recurrent genetic abnormalities, (ii) ‘AML’ representing acute myeloid leukaemia, minimally differentiated; acute myeloid leukaemia without maturation; acute myeloid leukaemia with maturation broadly representing FAB M0, M1 and M2 and (iii) ‘lineage’ representing acute myelomonocytic leukaemia; acute monoblastic leukaemia; acute erythroid leukaemia (erythroid/myeloid and pure erythroid leukaemia); acute megakaryoblasic leukaemia and acute basophilic leukaemia broadly representing FAB M4 – M7 indicated that a significant number of patients in the AML group had MGEA6 present calls compared with patients in the lineage and recurrent groups (p=0.0185). However RAGE-1 expression did not segregate based on WHO this grouping. We examined whether in our patients population the M0/1/2 FAB subgroups were associated with a poorer survival rate than M3/4/5/6/7 and this was not found to be the case (p=0.27). RAGE-1 and MGEA6 present calls were also not found to be associated with poorer survival (p=0.891 and 0.956, respectively). RAGE-1 present calls did not to segregate with any single cytogenetic risk group (good, standard or poor). However using Chi2 pairwise comparisons the frequency of MGEA6 present calls in good versus poor, good versus standard and standard versus poor cytogenetic risk groups were all highly significant (each p<0.0001). This is the first study to suggest a differential expression of a CT antigen based on FAB or WHO subgroup or cytogenetic risk group. In addition, MGEA6 and RAGE-1 may provide suitable targets for the immunotherapy of AML particularly for patients in the M0, M1 and M2 subgroup
The leukaemia associated antigen, SSX2IP, is expressed during mitosis on the surface of myeloid leukaemia cells
No full textWe have shown for the first time the surface expression pattern of SSX2IP during mitosis which provides an interesting insight into SSX2IP protein expression in human malignancy. Therapeutically the removal of SSX2IP positive cells from AML patient stem cell harvests has the potential to reduce the tumour burden for patients whose graft fails or for patients who lack a suitable stem cell donor, although these possibilities require further investigatio
Optimised SEREX technique for the identification of leukaemia associated antigens
No full textThe serological analysis of antigens by recombinant expression cloning (SEREX) has been used by many laboratories to immunoscreen lambda phage cDNA libraries produced from a range of tumour cell types. We and others have found it difficult to extract an optimal quality and quantity of mRNA for the preparation of cDNA libraries which represent the genes transcribed in haematological samples. The difficulty is believed to be due to residual haem groups in the isolated RNA sample which inhibit the activity of reverse transcriptase used in the later production of cDNA. During our preparation of a cDNA library for SEREX studies, we optimised the isolation of mRNA from samples from patients with haematological malignancies. We compared the efficacy of different methods of mRNA extraction using a range of haematological sample sizes and describe the most efficient techniques to maximise mRNA yield and quality for cDNA library production. The phage library we prepared contained a range of cDNA insert sizes, including high molecular weight sequences which, following immunoscreening with autologous patient sera, led to the isolation of 17 novel antigens. Using the methodology described, we have shown SEREX to be effective for the isolation of leukaemia-associated antigens, which may act as targets for immunotherap
A novel zinc finger gene, ZNF465, is inappropriately expressed in acute myeloid leukaemia cells
No full textTo increase our knowledge of leukaemia-associated antigens, especially in acute myeloid leukaemia (AML) M4, we prepared a phage display cDNA library using mRNA from the bone marrow cells of a patient with AML M4 at diagnosis. We immunoscreened 10 pfu with autologous sera and identified an antigen which we named GKT-AML8. The cDNA showed more than 99% similarity to a sequence on 2q21.2 and 95% sequence similarity to a sequence on 19q13.3. These genes were named ZNF465 and ZNF466, respectively, following HUGO Gene Nomenclature Committee (HGNC) guidelines. Expressed sequence tag data suggests that both genes are transcriptionally active. ZNF465 and ZNF466 encode a 5′ krüppel associated box domain typical of negative regulators of gene transcription. We have confirmed the translational start site in the +1 frame in a near-Kozak sequence that produces a 102 amino acid polypeptide from ZNF465. The high level of sequence similarity between ZNF465 and ZNF466 makes their transcripts almost indistinguishable by real-time polymerase chain reaction (RT-PCR). However, GKT-AML8 showed most sequence similarity to ZNF465 and no transcript matching the 3′ ZNF466 sequence could be detected in patient samples or healthy volunteers. ZNF465/466 expression was detectable in 12/13 AML and 10/14 chronic myeloid leukaemia patients' samples but not in normal donor peripheral blood (0/8) or 0/3 bone marrow samples which had been separated into CD34 and CD34 samples. The altered expression of ZNF465/466 in patients' samples and its absence in healthy donor haematopoietic samples indicate that ZNF465 is overexpressed in early myeloid disease and as such may represent a promising target for immunotherapy
Van‐den Berghe’s 5q‐ syndrome in 2008
No full textVan Den Berghe established 5q- syndrome as a discrete clinical entity in 1974 when he described patients with macrocytic anaemia, thrombocytosis, dyserythropoiesis, hypolobulated megakaryocytes and an interstitial deletion within chromosome 5q. With del(5q) as the sole cytogenetic abnormality, 5q- syndrome represents an opportunity to define precisely the molecular defect(s) underlying the pathogenesis of this disease. The commonly deleted region in 5q- syndrome, which is distinct from that in patients with complex cytogenetic changes that include del(5q), includes the ribosomal protein S14 locus and it has been proposed that that loss of an RPS14 allele accounts for the 5q- syndrome phenotype. However, this hypothesis fails to explain the growth advantage of the 5q- syndrome clone and it is evident that ribosomal protein defects are not specific to 5q- syndrome, as they are found in other bone marrow failure syndromes. Lenalidomide therapy leads to normalization of both haematological and cytogenetic parameters in the majority of 5q- syndrome patients. This review examines the potential role of several genes, including RPS14, in the pathogenesis of the 5q- syndrome and recent advances in clinical management, with particular emphasis on the role and mechanism of action of lenalidomide
Humoral detection of leukaemia-associated antigens in presentation acute myeloid leukaemia
No full textThe serological analysis of recombinant cDNA expression libraries (SEREX) technique was used to immunoscreen a testes cDNA expression library with sera from newly diagnosed acute myeloid leukaemia (AML) patients. We used a testis cDNA library to aid our identification of cancer-testis (CT) antigens. We identified 44 antigens which we further immunoscreened with sera from AML, chronic myeloid leukaemia (CML), and normal donors. Eight antigens were solely recognised by patient sera including the recently described CT antigen, PASD1, and the cancer-related SSX2 interacting protein, SSX2IP. RT-PCR analysis indicated that we had identified three antigens which were expressed in patient bone marrow (BM) and peripheral blood (PB) but not in normal donor samples (PASD1, SSX2IP, and GRINL1A). Real-time PCR (RQ-PCR) confirmed the restricted expression of PASD1 in normal donor organs. Antigen presentation assays using monocyte-derived dendritic cells (mo-DCs) showed that PASD1 could stimulate autologous T-cell responses, suggesting that PASD1 could be a promising target for future immunotherapy clinical trial
Development of a whole cell vaccine for acute myeloid leukaemia
No full textWe describe the modification of tumour cells to enhance their capacity to act as antigen presenting cells with particular focus on the use of costimulatory molecules to do so. We have been involved in the genetic modification of tumour cells to prepare a whole cell vaccine for nearly a decade and we have a particular interest in acute myeloid leukaemia (AML). AML is an aggressive and difficult to treat disease especially for patients for whom haematopoietic stem cell (HSC) transplant is not an option. AML patients who have a suitable donor and meet HSC transplant fitness requirements, have a 5 year survival of 50%, however for patients with no suitable donor or for which age is a factor, the prognosis is much worse. It is particularly poor prognosis patients, who are not eligible for HSC transplant, who are likely to benefit most from immunotherapy. It would be hoped that immunotherapy would be used to clear residual tumour cells in these patients in the first remission following standard chemotherapy treatments and that this will extend the remission and reduce the risk of a second relapse associated with disease progression and poor mortality rates. In this symposia report we will focus on whole cell vaccines as an immunotherapeutic option with particular reference to their use in the treatment of AML. We will aim to provide a brief overview of the latest data from our group and considerations for the use of this treatment modality in clinical trials for AM
- …
