ABSTRACT
In newly diagnosed acute myeloid leukemia (AML), immediate initiation of treatment is standard of care. However, deferral of antileukemic therapy may be indicated to assess comorbidities or pretherapeutic risk factors. We explored the impact of time from diagnosis to treatment on outcomes in newly diagnosed AML undergoing venetoclax-based therapy in two distinct cohorts. By querying the Study Alliance Leukemia database and the global health network TriNetX, we identified 138 and 717 patients respectively with an average age of 76 and 72 years who received venetoclax-based first-line therapy. When comparing patients who started treatment earlier or later than 10 days after initial diagnosis, no significant difference in median overall survival was observed - neither in the SAL cohort (7.7 vs. 9.6 months; P=0.42) nor in the TriNetX cohort (7.5 vs. 7.2 months; P=0.41). Similarly, severe infections, bleeding, and thromboembolic events were equally observed between early and later treatments, both in the overall patient groups and specific subgroups (age ≥75 years or leukocytes ≥20x109/L). This retrospective analysis indicates that delaying the start of venetoclax-based therapy in newly diagnosed AML might be a safe option for selected patients, provided that close clinical monitoring is performed.
Subject(s)
Bridged Bicyclo Compounds, Heterocyclic , Leukemia, Myeloid, Acute , Sulfonamides , Humans , Bridged Bicyclo Compounds, Heterocyclic/therapeutic use , Bridged Bicyclo Compounds, Heterocyclic/administration & dosage , Sulfonamides/therapeutic use , Sulfonamides/administration & dosage , Leukemia, Myeloid, Acute/drug therapy , Leukemia, Myeloid, Acute/mortality , Leukemia, Myeloid, Acute/diagnosis , Aged , Male , Female , Aged, 80 and over , Middle Aged , Time-to-Treatment , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Treatment Outcome , Adult , Retrospective Studies , Antineoplastic Agents/therapeutic useABSTRACT
Phage display technology (PD) is a powerful technique for the generation of tumortargeting antibodies. However, there are a number of different selection methods established in different laboratories around the world. Cellbased PD panning methods using primary tumor cells are particularly heterogeneous between laboratories, which can lead to inconsistent results. Therefore, the present study evaluated different cellbased PD selection methods regarding their potential to generate acute myeloid leukemia (AML) blastbinding antibodies. In addition to this evaluation, the present study improved the PD procedure by optimizing selection as well as depletion strategies. To the best of our knowledge, the current study demonstrated for the first time that antigen diversity during the depletion step is of importance for the enrichment of tumortargeting phage antibodies. It is demonstrated that medium levels of depletion antigen diversity led to the most promising antibody candidates. In addition, it was determined that purification of blast cells from patients with AML by immunomagnetic separation ameliorated the selection of AMLbinding phages during panning. Furthermore, suggesting a common designrelated mechanism using a 'singlepot' PD library, such as the wellknown Tomlinson singlechain fragment variable (scFv) library, the present study identified specific binding consensus phage particles in independent panning procedures. By means of these optimized strategies, four promising AML blastbinding phage particles were isolated and soluble scFvFc (scFv cloned to a fragment crystallizable of an IgG2a mouse antibody) fusion proteins were produced. These scFvFc antibodies bound the surface of AML blasts and were successfully internalized into their cytoplasm, indicating that they are potential immunoconjugate candidates for AML immunotherapy.
Subject(s)
Antibodies, Monoclonal/immunology , Antibodies, Neoplasm/immunology , Cell Surface Display Techniques/methods , Immunotherapy/methods , Leukemia, Myeloid, Acute/therapy , Antibody Specificity , Bacteriophages/immunology , HEK293 Cells , Humans , Primary Cell CultureABSTRACT
Few data exist on health-related quality of life (QoL) in patients with metastatic pancreatic cancer (mPC) receiving first-line chemotherapy (Awad L ZE, Mesbah M Boston, MA. Applying survival data methodology to analyze quality of life data, in Mesbah M, Cole BF, Ting Lee M-L (eds): Statistical Methods for Quality of Life Studies: Design, Measurements and Analysis. Kluwer Academic Publishers 2002). The QOLIXANE study is a prospective, noninterventional, multicenter substudy of the Platform for Outcome, Quality of Life and Translational Research on Pancreatic Cancer (PARAGON) registry, which evaluated QoL in patients with mPC receiving first-line gemcitabine and nab-paclitaxel chemotherapy in real-life setting. QoL was prospectively measured via EORTC QLQ-C30 questionnaires at baseline and every month thereafter. Therapy and efficacy parameters were prospectively collected. Main objectives were the rate of patients without deterioration of Global Health Status/QoL (GHS/QoL) at 3 and 6 months. Six hundred patients were enrolled in 95 German study sites. Median progression-free survival was 5.9 months (95% confidence interval [CI], 5.2-6.3). Median overall survival (OS) was 8.9 months (95% CI, 7.9-10.2), while median time to deterioration of GHS/QoL was 4.7 months (95% CI, 4.0-5.6). With a baseline GHS/QoL score of 46 (SD, 22.8), baseline QoL of the patients was severely impaired, in most cases due to loss in role functioning and fatigue. In the Kaplan-Meier analysis, 61% and 41% of patients had maintained GHS/QoL after 3 and 6 months, respectively. However, in the QoL response analysis, 35% and 19% of patients had maintained (improved or stable) GHS/QoL after 3 and 6 months, respectively, while 14% and 9% had deteriorated GHS/QoL with the remaining patients being nonevaluable. In the Cox regression analysis, GHS/QoL scores strongly predicted survival with a hazard ratio of 0.86 (P < .0001). Patients with mPC have poor QoL at baseline that deteriorates within a median of 4.7 months. Treatment with gemcitabine and nab-paclitaxel is associated with maintained QoL in relevant proportions of patients. However, overall, results remain poor, reflecting the aggressive nature of the disease.
Subject(s)
Adenocarcinoma/drug therapy , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Pancreatic Neoplasms/drug therapy , Quality of Life , Adult , Aged , Aged, 80 and over , Albumins/therapeutic use , Deoxycytidine/analogs & derivatives , Deoxycytidine/therapeutic use , Female , Humans , Male , Middle Aged , Paclitaxel/therapeutic use , Registries , Treatment Outcome , GemcitabineABSTRACT
Dyskeratosis congenita (DKC) is a paradigmatic telomere disorder characterized by substantial and premature telomere shortening, bone marrow failure, and a dramatically increased risk of developing myelodysplastic syndrome (MDS) or acute myeloid leukemia (AML). DKC can occur as a late-onset, so-called cryptic form, with first manifestation in adults. Somatic MDS-related mutations are found in up to 35% of patients with acquired aplastic anemia (AA), especially in patients with short telomeres. The aim of our study was to investigate whether cryptic DKC is associated with an increased incidence of MDS-related somatic mutations, thereby linking the accelerated telomere shortening with the increased risk of MDS/AML. Samples from 15 adult patients (median age: 42 years, range: 23-60 years) with molecularly confirmed cryptic DKC were screened using next-generation gene panel sequencing to detect MDS-related somatic variants. Only one of the 15 patients (7%) demonstrated a clinically relevant MDS-related somatic variant. This incidence was dramatically lower than formerly described in acquired AA. Based on our data, we conclude that clonal evolution of subclones carrying MDS-related mutations is not the predominant mechanism for MDS/AML initiation in adult cryptic DKC patients.
Subject(s)
Biomarkers, Tumor/genetics , Dyskeratosis Congenita/genetics , Leukemia, Myeloid, Acute/genetics , Mutation , Myelodysplastic Syndromes/genetics , Telomere Shortening/genetics , Adult , Dyskeratosis Congenita/complications , Female , Follow-Up Studies , Germany/epidemiology , Humans , Incidence , Leukemia, Myeloid, Acute/epidemiology , Male , Middle Aged , Myelodysplastic Syndromes/epidemiology , Prognosis , Young AdultABSTRACT
BACKGROUND: In head and neck squamous cell carcinoma (HNSCC), the occurrence of concurrent lung malignancies poses a significant diagnostic challenge because metastatic HNSCC is difficult to discern from second primary lung squamous cell carcinoma (SCC). However, this differentiation is crucial because the recommended treatments for metastatic HNSCC and second primary lung SCC differ profoundly. METHODS: We analyzed the origin of lung tumors in 32 patients with HNSCC using human papillomavirus (HPV) typing and targeted next generation sequencing of all coding exons of tumor protein 53 (TP53). RESULTS: Lung tumors were clearly identified as HNSCC metastases or second primary tumors in 29 patients, thus revealing that 16 patients had received incorrect diagnoses based on clinical and morphological data alone. CONCLUSION: The HPV typing and mutation analysis of all TP53 coding exons is a valuable diagnostic tool in patients with HNSCC and concurrent lung SCC, which can help to ensure that patients receive the most suitable treatment.
Subject(s)
Head and Neck Neoplasms/etiology , Lung Neoplasms/etiology , Neoplasms, Second Primary/diagnosis , Papillomaviridae/isolation & purification , Squamous Cell Carcinoma of Head and Neck/etiology , Tumor Suppressor Protein p53/genetics , Adult , Aged , Female , Head and Neck Neoplasms/pathology , Humans , Lung Neoplasms/pathology , Male , Middle Aged , Mutation/genetics , Neoplasms, Second Primary/etiology , Squamous Cell Carcinoma of Head and Neck/pathologyABSTRACT
Myelodysplastic syndromes are hematological neoplasias in which immunohistologic examination of bone marrow trephines is important for a definite diagnosis. Unequivocal distinction from reactive bone marrow changes is, however, sometimes difficult. Because neoplastic clones in myelodysplastic syndrome carry mutations in recurrent genes, mutation detection by targeted next-generation sequencing may be a useful support for differential diagnosis. To elucidate the accuracy of this approach in the clinical diagnostic setting, we analyzed single and consecutive bone marrow trephines processed for immunohistologic examination from 145 patients by targeted next-generation sequencing of 12 genes recurrently mutated in myelodysplastic syndromes. Of 110 patients with immunohistologic unequivocal diagnosis, 41 of 47 with myelodysplastic syndrome carried mutations. In 14 consecutive samples available from these patients, remissions were accompanied by loss of mutations and ongoing disease with persisting mutations. Of 35 samples with indefinite immunohistologic appearance, 22 developed clinical unequivocal myelodysplastic syndrome in the further course, and 19 carried mutations already in the initial biopsy, which persisted in consecutive samples available from 13 patients. No mutation was detected in any initial and consecutive sample of 13 patients with indefinite immunohistologic appearance without clinical unequivocal myelodysplastic syndrome in the further course. We conclude that targeted next-generation sequencing is an accurate tool for differential diagnosis of myelodysplastic syndrome in the clinical diagnostic setting.
Subject(s)
Bone Marrow/pathology , High-Throughput Nucleotide Sequencing/methods , Myelodysplastic Syndromes/diagnosis , Myelodysplastic Syndromes/genetics , Clone Cells , Diagnosis, Differential , Humans , Mutation/genetics , Mutation Rate , Myelodysplastic Syndromes/pathologyABSTRACT
BACKGROUND: Historical data indicate that surgical resection may benefit select patients with metastatic gastric and gastroesophageal junction cancer. However, randomized clinical trials are lacking. The current RENAISSANCE trial addresses the potential benefits of surgical intervention in gastric and gastroesophageal junction cancer with limited metastases. METHODS: This is a prospective, multicenter, randomized, investigator-initiated phase III trial. Previously untreated patients with limited metastatic stage (retroperitoneal lymph node metastases only or a maximum of one incurable organ site that is potentially resectable or locally controllable with or without retroperitoneal lymph nodes) receive 4 cycles of FLOT chemotherapy alone or with trastuzumab if Her2+. Patients without disease progression after 4 cycles are randomized 1:1 to receive additional chemotherapy cycles or surgical resection of primary and metastases followed by subsequent chemotherapy. 271 patients are to be allocated to the trial, of which at least 176 patients will proceed to randomization. The primary endpoint is overall survival; main secondary endpoints are quality of life assessed by EORTC-QLQ-C30 questionnaire, progression free survival and surgical morbidity and mortality. Recruitment has already started; currently (Feb 2017) 22 patients have been enrolled. DISCUSSION: If the RENAISSANCE concept proves to be effective, this could potentially lead to a new standard of therapy. On the contrary, if the outcome is negative, patients with gastric or GEJ cancer and metastases will no longer be considered candidates for surgical intervention. TRIAL REGISTRATION: The article reports of a health care intervention on human participants and is registered on October 12, 2015 under ClinicalTrials.gov Identifier: NCT02578368 ; EudraCT: 2014-002665-30.
Subject(s)
Adenocarcinoma/mortality , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Esophageal Neoplasms/mortality , Esophagectomy/mortality , Esophagogastric Junction/pathology , Gastrectomy/mortality , Quality of Life , Stomach Neoplasms/mortality , Adenocarcinoma/secondary , Adenocarcinoma/therapy , Combined Modality Therapy , Esophageal Neoplasms/pathology , Esophageal Neoplasms/therapy , Follow-Up Studies , Humans , Lymphatic Metastasis , Prognosis , Prospective Studies , Stomach Neoplasms/pathology , Stomach Neoplasms/therapy , Survival RateABSTRACT
BACKGROUND: Fludarabine-based chemoimmunotherapy with rituximab is frequently used in patients with indolent and mantle-cell lymphomas who relapse after alkylating chemotherapy. We aimed to compare the efficacy and safety of rituximab with bendamustine or fludarabine in patients with relapsed, indolent, non-Hodgkin lymphoma and mantle-cell lymphoma. METHODS: For this randomised, non-inferiority, open-label, phase 3 trial, we recruited patients from 55 centres in Germany, who were subsequently randomised centrally according to prespecified randomisation lists with permuted blocks of randomly variable block size to rituximab (375 mg/m(2), day 1) plus either bendamustine (90 mg/m(2), days 1 and 2) or fludarabine (25 mg/m(2), days 1-3) every 28 days for a maximum of six 28-day cycles. Patients were aged 18 years or older with a WHO performance status of 0-2 and had relapsed or refractory indolent or mantle-cell lymphoma; patients refractory to regimens that included rituximab, bendamustine, or purine analogue drugs were excluded. Patients were stratified by histological subtypes of lymphoma and by their latest previous therapies. Treatment allocation was not masked. The primary endpoint was progression-free survival and the final analysis was completed per protocol. Non-inferiority of bendamustine plus rituximab versus fludarabine plus rituximab was defined as a difference of less than 15% in 1-year progression-free survival. The protocol was amended in July, 2006, after approval of rituximab maintenance (375 mg/m(2) every 3 months for up to 2 years), which was then given to patients achieving a response to either trial treatment. This study is registered with ClinicalTrials.gov, number NCT01456351 (closed to enrolment, follow-up is ongoing). FINDINGS: Between Oct 8, 2003, and Aug 5, 2010, we randomly assigned 230 patients to treatment groups (116 bendamustine plus rituximab, 114 fludarabine plus rituximab). 11 patients were excluded for protocol violations and were not followed up further (two in the bendamustine plus rituximab group and nine in the fludarabine plus rituximab group). Thus, 219 patients were included in the per-protocol analysis (114 bendamustine plus rituximab, 105 fludarabine plus rituximab). 1-year progression-free survival with bendamustine plus rituximab was 0·76 (95% CI 0·68-0·84) and 0·48 (0·39-0·58) with fludarabine plus rituximab (non-inferiority p<0·0001). At a median follow-up of 96 months (IQR 73·2-112·9), median progression-free survival with bendamustine plus rituximab was 34·2 months (95% CI 23·5-52·7) and 11·7 months (8·0-16·1) with fludarabine plus rituximab (hazard ratio [HR] 0·54 [95% CI 0·38-0·72], log-rank test p<0·0001). Safety outcomes were similar in both groups, with 46 serious adverse events recorded (23 in the bendamustine plus rituximab group and 23 in the fludarabine plus rituximab group), most commonly myelosuppression and infections. INTERPRETATION: In combination with rituximab, bendamustine was more effective than fludarabine, suggesting that bendamustine plus rituximab may be the preferred treatment option for patients with relapsed indolent and mantle-cell lymphomas. FUNDING: Roche Pharma AG, Ribosepharm GmbH, Mundipharma GmbH, Studiengruppe indolente Lymphome (StiL).
Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Lymphoma, Mantle-Cell/drug therapy , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bendamustine Hydrochloride/administration & dosage , Bendamustine Hydrochloride/adverse effects , Disease-Free Survival , Female , Humans , Infections/chemically induced , Male , Middle Aged , Recurrence , Retreatment , Rituximab/administration & dosage , Rituximab/adverse effects , Survival Rate , Treatment Outcome , Vidarabine/administration & dosage , Vidarabine/adverse effects , Vidarabine/analogs & derivativesABSTRACT
HISTORY AND CLINICAL FINDINGS: A 77 year old female patient was admitted for the evaluation of hyponatremia and a generalized papulous exanthema with severe pruritus. INVESTIGATIONS AND DIAGNOSIS: The syndrome of inappropriate antidiuretic hormone secretion (SIADH) could be diagnosed as cause for hyponatremia. Biopsy of a soft tissue tumor revealed a T-cell lymphoma with widespread skelettal dissemination. TREATMENT AND COURSE: Chemotherapy caused a rapid response and improvement of general well-being. SIADH could be controlled by the specific vasopressin-2-receptor antagonist tolvaptan. CONCLUSIONS: In this patient, both the papulous exanthema and the SIADH are regarded as T-cell-lymphoma-associated paraneoplastic syndromes.
Subject(s)
Exanthema/etiology , Hyponatremia/etiology , Inappropriate ADH Syndrome/diagnosis , Lymphoma, T-Cell, Cutaneous/diagnosis , Paraneoplastic Syndromes/diagnosis , Pruritus/etiology , Aged , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Benzazepines/therapeutic use , Diagnosis, Differential , Disease Progression , Exanthema/drug therapy , Female , Humans , Hyponatremia/drug therapy , Inappropriate ADH Syndrome/drug therapy , Lymphoma, T-Cell, Cutaneous/drug therapy , Multimodal Imaging , Paraneoplastic Syndromes/drug therapy , Positron-Emission Tomography , Pruritus/drug therapy , Tolvaptan , Tomography, X-Ray ComputedABSTRACT
The current standard treatment for acute myeloid leukemia (AML) is chemotherapy based on cytarabine and daunorubicine (7 + 3), but it discriminates poorly between malignant and benign cells. Dose-limiting offtarget effects and intrinsic drug resistance result in the inefficient eradication of leukemic blast cells and their survival beyond remission. This minimal residual disease is the major cause of relapse and is responsible for a 5-year survival rate of only 24%. More specific and efficient approaches are therefore required to eradicate malignant cells while leaving healthy cells unaffected. In this study, we generated scFv antibodies that bind specifically to the surface of AML blast cells and AML bone marrow biopsy specimens. We isolated the antibodies by phage display, using subtractive whole-cell panning with AML M2derived Kasumi1 cells. By selecting for internalizing scFv antibody fragments, we focused on potentially novel agents for intracellular drug delivery and tumor modulation. Two independent methods showed that 4 binders were internalized by Kasumi-1 cells. Furthermore, we observed the AMLselective inhibition of cell proliferation and the induction of apoptosis by a recombinant immunotoxin comprising one scFv fused to a truncated form of Pseudomonas exotoxin A (ETA'). This method may therefore be useful for the selection of novel disease-specific internalizing antibody fragments, providing a novel immunotherapeutic strategy for the treatment of AML patients.
Subject(s)
ADP Ribose Transferases , Antibodies, Neoplasm , Bacterial Toxins , Blast Crisis/drug therapy , Exotoxins , Immunotoxins , Leukemia, Myeloid, Acute/drug therapy , Single-Chain Antibodies , Virulence Factors , ADP Ribose Transferases/genetics , ADP Ribose Transferases/immunology , ADP Ribose Transferases/pharmacology , Antibodies, Neoplasm/genetics , Antibodies, Neoplasm/immunology , Antibodies, Neoplasm/pharmacology , Antibody Specificity/genetics , Bacterial Toxins/genetics , Bacterial Toxins/immunology , Bacterial Toxins/pharmacology , Blast Crisis/immunology , Blast Crisis/pathology , Cell Line, Tumor , Exotoxins/genetics , Exotoxins/immunology , Exotoxins/pharmacology , Humans , Immunotoxins/genetics , Immunotoxins/immunology , Immunotoxins/pharmacology , Leukemia, Myeloid, Acute/immunology , Leukemia, Myeloid, Acute/pathology , Single-Chain Antibodies/genetics , Single-Chain Antibodies/immunology , Single-Chain Antibodies/pharmacology , Virulence Factors/genetics , Virulence Factors/immunology , Virulence Factors/pharmacology , Pseudomonas aeruginosa Exotoxin AABSTRACT
Myelodysplastic syndromes (MDS) are hematopoietic disorders characterized by ineffective hematopoiesis and progression to acute leukemia. In patients ineligible for hematopoietic stem cell transplantation, azacitidine is the only treatment shown to prolong survival. However, with the availability of a growing compendium of cancer biomarkers and related drugs, analysis of relevant genetic alterations for individual MDS patients might become part of routine evaluation. Therefore and in order to cover the entire bone marrow microenvironment involved in the pathogenesis of MDS, SNP array analysis and targeted next generation sequencing (tNGS) for the mostly therapy relevant 46 onco- and tumor-suppressor genes were performed on bone marrow biopsies from 29 MDS patients. In addition to the detection of mutations known to be associated with MDS in NRAS, KRAS, MPL, NPM1, IDH1, PTPN11, APC and MET, single nucleotide variants so far unrelated to MDS in STK11 (n=1), KDR (n=3), ATM (n=1) and JAK3 (n=2) were identified. Moreover, a recurrent microdeletion was detected in Xq26.3 (n=2), causing loss of PHF6 expression, a potential tumor suppressor gene, and the miR-424, which is involved in the development of acute myeloid leukemia. Finally, combined genetic aberrations affecting the VEGF/VEGFR pathway were found in the majority of cases demonstrating the diversity of mutations affecting different nodes of a particular signaling network as an intrinsic feature in MDS patients. We conclude that combined SNP array analyses and tNGS can identify established and novel therapy relevant genomic aberrations in MDS patients and track them in a clinical setting for individual therapy selection.
Subject(s)
Carrier Proteins/genetics , Chromosome Deletion , Chromosomes, Human, X , Genetic Testing/methods , High-Throughput Nucleotide Sequencing , Janus Kinase 3/genetics , MicroRNAs/genetics , Myelodysplastic Syndromes/genetics , Oligonucleotide Array Sequence Analysis , Polymorphism, Single Nucleotide , Bone Marrow/enzymology , Bone Marrow/pathology , Case-Control Studies , Female , Genetic Markers , Genetic Predisposition to Disease , Humans , Immunohistochemistry , Male , Myelodysplastic Syndromes/enzymology , Myelodysplastic Syndromes/pathology , Nucleophosmin , Phenotype , Repressor Proteins , Risk Factors , Signal Transduction/geneticsSubject(s)
Adenocarcinoma/pathology , Colonic Neoplasms/pathology , High-Throughput Nucleotide Sequencing/methods , Lung Neoplasms/pathology , Neoplasms, Multiple Primary/pathology , Adenocarcinoma/genetics , Aged , Colonic Neoplasms/genetics , Diagnosis, Differential , Female , Humans , Lung Neoplasms/genetics , Mutation , Neoplasms, Multiple Primary/genetics , Sequence Analysis, DNAABSTRACT
Protein tyrosine phosphatase interacting protein 51 (PTPIP51) is known to be expressed in blood cells with restriction to the myeloid lineage. All myeloid progenitor cells are PTPIP51 positive except for the myeloblasts. To define the expression of PTPIP51 in acute myeloid leukemia (AML), we performed immunohistochemical experiments with peptide specific antibodies (C-terminus, N-terminus and aas 114-129) to PTPIP51 with samples of AML bone marrow trephine biopsy specimens. AML blasts reacted positive for PTPIP51 protein encompassing the C-terminal sequence. Healthy bone marrow displayed an exclusive staining for the N-terminal containing form of PTPIP51. Moreover, PTPIP51 protein was highly phosphorylated at its tyrosine 176 residue. Acquired confocal images of AML cells displayed an absence of PTP1B and revealed a co-localization of PTPIP51 and Lyn. Duolink proximity ligation assays (DPLA) corroborated an interaction for PTPIP51 with Lyn and c-Src. In AML blasts rarely an interaction of PTPIP51 with PTP1B and Raf-1 was seen. Furthermore, DPLA signals were also obtained for PTPIP51 and c-Kit in AML cells. Therefore, PTPIP51 was identified as a new signal molecule of the c-Kit signaling pathway. By the phosphorylation done by Lyn, c-Src and c-Kit, PTPIP51 is prevented to influence mitogen activated protein kinase pathway on Raf-1 level contributing to increased proliferation of AML cells.
Subject(s)
Bone Marrow/metabolism , Gene Expression , Leukemia, Myeloid, Acute/metabolism , Myeloid Progenitor Cells/metabolism , Signal Transduction , Adult , Antibodies/analysis , Bone Marrow/pathology , CSK Tyrosine-Protein Kinase , DNA Probes , Female , Humans , Immunohistochemistry , Leukemia, Myeloid, Acute/genetics , Leukemia, Myeloid, Acute/pathology , Microscopy, Fluorescence , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Myeloid Progenitor Cells/pathology , Phosphorylation , Protein Processing, Post-Translational , Protein Tyrosine Phosphatase, Non-Receptor Type 1/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 1/metabolism , Protein Tyrosine Phosphatases/genetics , Protein Tyrosine Phosphatases/metabolism , Protein-Tyrosine Kinases/genetics , Protein-Tyrosine Kinases/metabolism , Proto-Oncogene Proteins c-kit/genetics , Proto-Oncogene Proteins c-kit/metabolism , RNA, Messenger/analysis , Reverse Transcriptase Polymerase Chain Reaction , Signal Transduction/genetics , Tyrosine/metabolism , src-Family Kinases/genetics , src-Family Kinases/metabolismSubject(s)
Graft Rejection/drug therapy , Granulocyte Colony-Stimulating Factor/therapeutic use , Hematopoietic Stem Cell Transplantation/adverse effects , Leukemia, Lymphocytic, Chronic, B-Cell/therapy , Stem Cell Factor/analogs & derivatives , Drug Therapy, Combination , Hematopoietic Stem Cell Transplantation/methods , Humans , Leukemia, Lymphocytic, Chronic, B-Cell/complications , Male , Middle Aged , Stem Cell Factor/therapeutic use , Treatment OutcomeABSTRACT
OBJECTIVE: Plasticity of hematopoietic stem cells (HSC) has gained major interest in stem cell research. In order to investigate whether HSC may differentiate into mesenchymal stem cells (MSC), we assessed chimerism in peripheral blood (PB), mononuclear cell fractions (MNC) of bone marrow, and MSC derived from bone marrow (BM) from 27 up to 4225 days after allogeneic transplantation. PATIENTS AND METHODS: We applied fluorescence in situ hybridization using X/Y gene probes in sex-mismatched and STR-PCR in sex-matched patients. MSC could have been generated in 27 of 55 bone marrow samples derived from 20 patients. Fifteen patients received peripheral blood stem cell transplants (PBSCT), including CD34-selected PBSCT in two. Five patients received bone marrow. RESULTS: While all patients had chimerism in PB and MNC of the BM, in all but one patient BM-derived MSC were of recipient origin. This single patient showed reproducibly MSC of donor origin in a frequency of 1% after having received a CD34-selected PBSCT. Looking at graft collections, MSCs were easily generated from BM specimens, while no MSC could be derived from PBSC samples. CONCLUSION: Even though HSC have been found to differentiate into a variety of nonhematological cell types, they usually do not differentiate into MSC after allogeneic transplantation.
Subject(s)
Bone Marrow Transplantation , Hematologic Neoplasms/surgery , Mesoderm/cytology , Stem Cell Transplantation , Stem Cells/cytology , Transplantation, Homologous , Adolescent , Adult , Aged , Female , Humans , In Situ Hybridization, Fluorescence , Male , Middle Aged , Polymerase Chain ReactionABSTRACT
The outcome of allogeneic stem cell transplantation depends upon the disease status before transplantation. Patients with refractory disease are at high risk for relapse. To improve the curative potential of the transplant procedure, we treated 3 chemotherapy-refractory CLL patients with alemtuzumab before allogeneic stem cell transplantation. Prior to therapy, all patients suffered from B-symptoms, and had massive adenopathy, splenomegaly, thrombocytopenia, and anemia; two patients had hepatomegaly. Alemtuzumab greatly reduced tumor mass in blood and bone marrow, B-symptoms resolved, and organomegaly improved. Two patients became blood product independent. All patients proceeded to transplantation after conditioning with TBI 2 Gy (n=1) or Treosulfan (n=2) in combination with Fludarabine either from an HLA-matched sibling (n=2) or from an HLA-matched unrelated donor (n=1). All patients engrafted, and are alive and well. Two patients reached complete remission (CR); one patient attained stable partial remission (PR). These heavily pre-treated refractory patients gained substantial clinical benefit from alemtuzumab, and received successful allografts.