Malignancies Of B-cell Lineage Research Articles

P1596: PREDIAGNOSTIC ANTIMICROBIAL USE IN CLL, MM, FL AND DLBCL

Background: Chronic lymphocytic leukemia (CLL), diffuse large B-cell lymphoma (DLBCL), follicular lymphoma (FL) and multiple myeloma (MM) are B-cell lineage malignancies all sharing an immune dysfunction leading to an increased risk of infection. CLL, FL and MM are preceded by indolent precursor states; more specifically monoclonal B-cell lymphocytosis (MBL), in situ follicular neoplasia (ISFN), and monoclonal gammopathy of uncertain significance (MGUS), respectively. MBL, ISFN and MGUS may be detected decades prior to overt malignancy. Although CLL and FL may transform into DLBCL, evidence for a premalignant DLBCL precursor is scarce. We have previously demonstrated an increased use of antibiotics up to 20 years prior to CLL diagnosis (Andersen et al. Leukemia. 2020). Whether patients with DLBCL, FL or MM share the same trait as patients with CLL remains unknown. Aims: To assess use of antimicrobials for patients with FL, DLBCL and MM prior to diagnosis Methods: We included all patients diagnosed with CLL since 2008, small lymphocytic lymphoma (SLL), DLBCL, FL and symptomatic MM since 2005 through Danish national patient registries (DCLLR, LYFO and DaMyDa; https://www.rkkp.dk/). We analyzed patients with CLL and SLL jointly, as they are recognized as the same disease entity and treated similarly. Likewise, patients with FL grade 3b are clinically similar to DLBCL, thus patients with FL treated with R-CHOP-like regimens within 3 months of diagnosis were considered grade 3b and analyzed together with DLBCL. Data on antimicrobial (AM) prescriptions (Rx) were retrieved from the Danish national database for reimbursed prescriptions (DNDRP) using WHO ATC codes. To characterize the use of prediagnostic AM use, we included AM Rx from January 2004 until date of diagnosis. Patients with multiple malignancies were classified according to the first occurring diagnosis. Statistical analyses were performed using R software. Results: We followed 21,822 patients for a mean of 9.8 person-years prior to diagnosis (SD+/- 4.8), from which a total of 138,805 AM Rx were identified for 18,840 (86.3%) distinct patients. Within the cohort, 6377 (29.2%) were diagnosed with CLL accounting for 42,107 (30.33%) AM Rx, 5803 (26.6%) were diagnosed with MM accounting for 38,417 (27.7%) AM Rx, 6735 (30.9%) were diagnosed with DLBCL accounting for 41,623 (30.0%) AM Rx, and 2907 (13.3%) were diagnosed with FL accounting for 16,658 (12.0%) AM Rx. Thus, 2982 (13.7%) patients had no Rx prior to diagnosis of whom 989 (33.2%) had DLBCL, 775 (26.0%) had CLL, 722 (24.2%) had MM, and 496 (16.6%) had FL. Stratified by disease, patients later diagnosed with CLL and MM accounted for more AM Rx than patients later diagnosed with DLBCL and FL (45.0% vs 41.6% vs 37.8% vs 35.4% with >3 AM Rx, respectively; Table 1). In particular, more penicillin and macrolide were prescribed prior to diagnosis of CLL and MM compared to patients later diagnosed with DLBCL and FL. Image:Summary/Conclusion: These preliminary results indicate a higher rate of infections, as assessed by number of AM Rx, in individuals later developing CLL and MM compared to individuals later developing DLBCL and FL. Thus, MM and CLL seems to be prone to immune dysfunction also prior to diagnosis. Whether immune dysfunction plays a role in development of the disease or is due to the premalignant MBL and MGUS warrants further investigations.

CD19-directed CAR T-cell therapy for treatment of primary CNS lymphoma

AbstractCD19-directed chimeric antigen receptor (CD19CAR) T-cell therapy has been successful in treating several B-cell lineage malignancies, including B-cell non-Hodgkin lymphoma (NHL). This modality has not yet been extended to NHL manifesting in the central nervous system (CNS), primarily as a result of concerns for potential toxicity. CD19CAR T cells administered IV are detectable in cerebrospinal fluid (CSF), suggesting that chimeric antigen receptor (CAR) T cells can migrate from the periphery into the CNS, where they can potentially mediate antilymphoma activity. Here, we report the outcome of a subset of patients with primary CNS lymphoma (PCNSL; n = 5) who were treated with CD19CAR T cells in our ongoing phase 1 clinical trial. All patients developed grade ≥ 1 cytokine release syndrome and neurotoxicity post-CAR T-cell infusion; toxicities were reversible and tolerable, and there were no treatment-related deaths. At initial disease response, 3 of 5 patients (60%; 90% confidence interval, 19-92%) seemed to achieve complete remission, as indicated by resolution of enhancing brain lesions; the remaining 2 patients had stable disease. Although the study cohort was small, we demonstrate that using CD19CAR T cells to treat PCNSL can be safe and feasible. This trial was registered at www.clinicaltrials.gov as #NCT02153580.

Title Point-of-Care Production of CD19 CAR-T Cells in an Automated Closed-System: Report of First Clinical Experience

Introduction CD19 CAR-T cell products were recently approved as therapy for advanced B-cell lineage malignancies. The predominant manufacturing model for this type of therapy is a centralized industrial-type production process. An attractive model of CAR-T cell production and delivery to the patient is via a point-of care-manufacturing process. We report on first cases of implementation of this approach in a setting of compassionate use program.Patients and methods Four patients with relapsed/refractory B-cell lineage malignancies were eligible for compassionate use of CD19 CAR-T cell therapy. Three patients, median age 15 years, had relapsed B-cell lineage acute lymphoblastic leukemia (B-ALL) after haploidentical hematopoietic stem cell transplantation (HSCT). Bone marrow disease burden at therapy start was 12%, 74% and 0,159. The patient with low minimal residual disease (MRD) in the bone marrow had skeletal involvement with multiple lymphomatous mass lesions. One patient had refractory primary mediastinal B-cell lymphoma (PMBCL). The CliniMACS Prodigy T cell transduction (TCT) process was used to produce CD19 CAR-T cells from patient-derived leukapheresis product. Automatic production included CD4/CD8 selection, CD3/CD28 stimulation with MACS GMP T Cell TransAct, transduction with lentiviral (second generation CD19.4-1BB zeta) vector (Lentigen, Miltenyi Biotec company) and expansion over 12 days in the presence of TexMACS GMP Medium supplemented with MACS GMP IL-7/IL-15 combination. Final product was administered without cryopreservation to the patients after fludarabine/cyclophosphamide preconditioning. All patients received prophylactic tocilizumab 1 hour before CAR-T cell infusion at 8mg/kg.Results All production cycles were successful. Median transduction efficacy achieved was 57%(52-63). Median expansion of T cells was x26(24-43). CD4/CD8 ratio in the final product was 0,750,22-6). All final products passed the in-process and quality controls. The cell products were administered at a dose of 1*106/kg of CAR-T cells. No immediate infusion reactions were reported. In 2 cases mild cytokine release syndrome (CRS) was diagnosed. In one case mild CAR-T cell related encephalopathy developed. In one case additional dose of tocilizumab and one dose of dexamethasone were administered to control CRS and encephalopathy. All patients survived to the point of response evaluation. In 3 cases CAR-T cell expansion was detected to a maximum 25%. MRD-negative responses detected by flow cytometry and PCR were achieved in 2 cases with bone marrow involvement. In two cases with prominent mass lesions an objective response was documented. In the patient with 74% blast in bone marrow at start of therapy, neither CAR-T cell expansion nor leukemia response were documented. Details of therapy and response are summarized in table 1.Conclusion Production of CAR-T cells with the CliniMACS Prodigy TCT process is a feasible and an attractive option that provides a point-of-care manufacturing approach to enable rapid delivery of CAR-T cells to patients in need. Robustness and consistency of this approach provides a solid basis for multi-center academic trials in the field of adoptive cell therapy. DisclosuresDropulic:Lentigen, A Miltenyi Biotec company: Employment. Shneider:Lentigen, A Miltenyi Biotec company: Employment. Orentas:Lentigen, A Miltenyi Biotec company: Employment. Alex:Miltenyi Biotec: Employment. Essl:Miltenyi Biotec: Employment.

Phosphorylated immunoreceptor tyrosine-based activation motifs and integrin cytoplasmic domains activate spleen tyrosine kinase via distinct mechanisms

Spleen tyrosine kinase (Syk) is involved in cellular adhesion and also in the activation and development of hematopoietic cells. Syk activation induced by genomic rearrangement has been linked to certain T-cell lymphomas, and Syk inhibitors have been shown to prolong survival of patients with B-cell lineage malignancies. Syk is activated either by its interaction with a double-phosphorylated immunoreceptor tyrosine-based activation motif (pITAM), which induces rearrangements in the Syk structure, or by the phosphorylation of specific tyrosine residues. In addition to its immunoreceptor function, Syk is activated downstream of integrin pathways, and integrins bind to the same region in Syk as does pITAM. However, it is unknown whether integrins and pITAM use the same mechanism to activate Syk. Here, using purified Syk protein and fluorescence-based enzyme assay we investigated whether interaction of the integrin β3 cytoplasmic domain with the Syk regulatory domain causes changes in Syk activity similar to those induced by pITAM peptides. We observed no direct Syk activation by soluble integrin peptide, and integrin did not compete with pITAM-induced activation even though at high concentrations, the integrin cytoplasmic domain peptide competed with Syk's substrate. However, clustered integrin peptides induced Syk activation, presumably via a transphosphorylation mechanism. Moreover, the clustered integrins also activated a Syk variant in which tyrosines were replaced with phenylalanine (Y348F/Y352F), indicating that clustered integrin-induced Syk activation involved other phosphorylation sites. In conclusion, integrin cytoplasmic domains do not directly induce Syk conformational changes and do not activate Syk via the same mechanism as pITAM.

Persistence of long-lived plasma cells and humoral immunity in individuals responding to CD19-directed CAR T-cell therapy

AbstractThe mechanisms underlying the maintenance of long-lasting humoral immunity are not well understood. Studies in mice indicate that plasma cells (PCs) can survive up to a lifetime, even in the absence of regeneration by B cells, implying the presence of long-lived PCs as a mechanism for long-lasting immunity. Evidence from humans treated with anti-CD20, which depletes circulating B cells, also suggests B-cell–independent long-term survival of some PCs. On the other hand, antibody responses may be sustained solely by short-lived PCs with repopulation from clonally related memory B cells. To explore PC longevity and humoral immunity in humans, we investigated the fate of PCs and their antibodies in adult and pediatric patients who received chimeric antigen receptor–based adoptive T-cell immunotherapy targeting CD19 to treat B-cell lineage malignancies (CTL019). Treatment with CTL019 is frequently associated with B-cell aplasia that can persist for years. Serum antibody titers to vaccine-related antigens were measured, and quantitative assessment of B cells and PCs in blood and bone marrow was performed at various time points before and after CTL019 therapy. While total serum immunoglobulin concentrations decline following CTL019-induced B-cell aplasia, several vaccine/pathogen-specific serum immunoglobulin G and A (IgG and IgA) titers remain relatively stable for at least 6 and 12 months posttreatment, respectively. Analysis of bone marrow biopsies after CTL019 revealed 8 patients with persistence of antibody-secreting PCs at least 25 months post-CTL019 infusion despite absence of CD19+CD20+ B cells. These results provide strong evidence for the existence of memory B-cell–independent, long-lived PCs in humans that contribute to long-lasting humoral immunity.

Abstract A44: The role of PHF6 in maintaining pre-B cell commitment in B-cell acute lymphoblastic leukemia

Abstract Loss of function mutations in the plant homeodomain factor 6 (PHF6) are responsible for the Börjeson–Forssman–Lehmann syndrome, a familial X-linked intellectual disability disorder, and are observed in approximately 20% of adult T-cell acute lymphoblastic leukemias (T-ALLs) and 3% of adult acute myeloid leukemias (AMLs). However, mutations in B-cell lineage malignancies are notably absent. Interestingly, our recent work has uncovered PHF6 as a positive growth regulator in B-cell acute lymphoblastic leukemia (B-ALL) through a genome-scale in vivo loss-of-function screen. To identify the molecular mechanism by which PHF6 acts to promote B-ALL growth in vivo, we utilized CRISPR-Cas9 to delete Phf6 in murine B-ALL cells. Transplantation of Phf6 knockout cells (Phf6KO) into immunocompetent syngeneic recipients significantly extends disease latency and survival, therefore validating PHF6 as a bona fide positive growth regulator of B-ALL in vivo. Strikingly, these mice develop lymphoma-like disease with complete penetrance, characterized by significantly enlarged lymph nodes, decreased disease burden in the spleen and increased expression of the canonical T-cell marker CD4, suggesting that Phf6KO B-ALL cells transdifferentiated to cells resembling those of the T-cell lineage. To dissect the mechanism by which PHF6 regulates this lineage decision, we carried out a combination of RNA sequencing and chromatin immunoprecipitation (ChIP) analyses in Phf6WT and Phf6KO cells. RNA sequencing analysis revealed many differentially expressed genes in Phf6KO B-ALL cells , including gene sets involved in pathways important for B-cell development. ChIP-sequencing analysis of PHF6 and several histone marks (H3K27Ac, H3K27me3, H3K4me3) in Phf6WT B-ALL cells revealed that PHF6 and H3K27Ac signals co-localize close to the transcription start site of a significant proportion of differentially expressed genes. Transcription factor binding motif analysis revealed significant enrichment for several well-described master regulators of B-cell development, including PU.1, EGR-1, EBF-1, NF-κB and TCF3/TCF12. Notably, a number of these predicted transcription factors co-immunoprecipitated with PHF6 in Phf6WT B-ALL cells. These findings reveal an essential role for PHF6 in the maintenance of B-cell identity in B-ALL by activating, directly or indirectly, genes that are crucial for B-cell lineage commitment. Collectively, these results indicate that loss-of-function of PHF6 in B-ALL leads to transdifferentiation to the T-cell lineage, potentially explaining the apparent absence of PHF6 mutations in human B cell-lineage malignancies. Citation Format: Yadira M. Soto-Feliciano, Jordan ME Bartlebaugh, Yunpeng Liu, Francisco J. Sánchez-Rivera, Abraham S. Weintraub, Arjun Bhutkar, Tyler E. Jacks, Richard A. Young, Michael T. Hemann. The role of PHF6 in maintaining pre-B cell commitment in B-cell acute lymphoblastic leukemia. [abstract]. In: Proceedings of the AACR Special Conference on Chromatin and Epigenetics in Cancer; Sep 24-27, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2016;76(2 Suppl):Abstract nr A44.

Immunoglobulin Heavy Chain Gene Rearrangement in Non B-cell Haematological Malignancies.

Clonality detection through amplifying immunoglobulin heavy chain (IGH) gene rearrangements by polymerase chain reaction (PCR) is a useful tool in diagnosis of various B-lymphoid malignancies. Immunoglobulin heavy chain gene rearrangement can be an optimal target for clonality detection in B-lymphoid malignancies. In the present study, we evaluated the presence of IGH gene rearrangement in non B-cell haemato-oncology patients including T-cell acute lymphoblastic leukaemia (T-ALL), acute myeloblastic leukaemia (AML) and biphenotypic leukaemia. We studied 18 cases of haematological malignancies which comprised five patients with T-ALL, 12 patients with AML and one with biphenotypic leukaemia. We found that the incidence of IGH gene rearrangement in T-ALL and AML were three (60%) and two (16.7%), respectively. The patient with biphenotypic leukaemia was negative for IGH gene rearrangement. Immunoglobulin gene rearrangement, which occurs in almost all haematological malignancies of B-cell lineage, also presents in a very small proportion of T-cell or myeloid malignancies.

The Ubiquitin+Proteasome Protein Degradation Pathway as a Therapeutic Strategy in the Treatment of Solid Tumor Malignancies

A concept that currently steers the development of cancer therapies has been that agents directed against specific proteins that facilitate tumorigenesis or maintain a malignant phenotype will have greater efficacy, less toxicity and a more sustained response relative to traditional cytotoxic chemotherapeutic agents. The clinical success of the targeted agent Imatinib mesylate as an inhibitor of the tyrosine kinase associated with the breakpoint cluster region-Abelson oncogene locus (BCR-ABL) in the treatment of Philadelphia-positive chronic myelogenous leukemia (CML) has served as a paradigm. While intellectually gratifying, the selective targeting of a single driver event by a small molecule, e.g., kinase inhibitor, to dampen a tumor-promoting pathway in the treatment of solid tumors is limited by many factors. Focus can alternatively be placed on targeting fundamental cellular processes that regulate multiple events, e.g., protein degradation, through the Ubiquitin (Ub)+Proteasome System (UPS). The UPS plays a critical role in modulating numerous cellular proteins to regulate cellular processes such as signal transduction, growth, proliferation, differentiation and apoptosis. Clinical success with the proteasome inhibitor bortezomib revolutionized treatment of B-cell lineage malignancies such as Multiple Myeloma (MM). However, many patients harbor primary resistance and do not respond to bortezomib and those that do respond inevitably develop resistance (secondary resistance). The lack of clinical efficacy of proteasome inhibitors in the treatment of solid tumors may be linked mechanistically to the resistance detected during treatment of hematologic malignancies. Potential mechanisms of resistance and means to improve the response to proteasome inhibitors in solid tumors are discussed.

PAX Immunoreactivity Identifies Alveolar Rhabdomyosarcoma

PAX5 is a member of the paired box transcription factors involved in development and its expression has been well characterized among hematopoietic malignancies of B-cell lineage. Its expression has also been reported in a subset of neuroendocrine carcinomas, urothelial tumors, Merkel cell carcinoma, glioblastoma, and neuroblastoma cell lines. As such, we sought to assess it as a diagnostic marker in the evaluation of pediatric small round blue cell tumors. Tumors selected for evaluation included embryonal rhabdomyosarcoma (55 cases), alveolar rhabdomyosarcoma (ARMS) (51 cases), neuroblastoma (22 cases), Wilms tumor (18 cases), Ewing Family of Tumors (11 cases), lymphoblastic lymphoma (8 cases), hepatoblastoma (6 cases), and granulocytic sarcoma (3 cases) as either cores in a tissue microarray or whole mount sections. All cases were immunostained using an antibody directed toward PAX5 and immunoreactivity was scored semiquantitatively according to percentage of nuclear staining. As expected, all B-cell lymphoblastic lymphomas were strongly immunoreactive against PAX5. Additionally, all Wilms tumors showed staining of variable intensity, most intensely in the epithelial component. Of the rhabdomyosarcoma cases, 34 of 51 (67%) ARMS were immunoreactive whereas none of the 55 embryonal rhabdomyosarcoma cases stained. No other tumor type on the array was immunoreactive toward PAX5. Genetic information was available on 7 ARMS, 5 of which had characteristic translocations involving PAX genes, either t(2:13) or t(1;13). Of the translocation-positive cases, all showed nuclear reactivity toward PAX5, and both the translocation-negative cases did not. Possible explanations of PAX5 staining include aberrant expression of the PAX5 transcription factor, PAX5 expression in normal tissue at the time the tumors most closely recapitulates in development or crossreactivity with another member of the PAX family. PAX3 and PAX7 fusion genes characterize the majority of ARMS making crossreactivity with these proteins an attractive theory, and suggest that PAX5 immunoreactivity may be specific for translocation-positive ARMS. Further study in a larger series of rhabdomyosarcomas is warranted to assess the sensitivity and specificity of PAX5 immunoreactivity for the ARMS variant.

Loss of Id4 Accelerates CLL Progression in TCL1 Mice

The inhibitor of DNA binding protein 4 (ID4) is a member of dominant negative basic helix loop helix (bHLH) transcription factor family that has a HLH domain but lacking DNA-binding domain. Methylation of ID4 in B-cell lineage malignancies including CLL and germinal center non-Hodgkin lymphomas (GC-NHLs) has been described. To date, the impact of Id4 loss in CLL has not been demonstrated. We utilized the TCL1 transgenic mouse model of human CLL to study the importance of loss of ID4 in disease progression. We demonstrated that ID4 was silenced by methylation only at the time mice had symptomatic leukemia. We therefore sought to investigate if earlier loss of Id4 would accelerate CLL progression. We generated mice with haploid loss of Id4 in TCL1 transgenic background by breeding homozygous TCL1 transgenic mice and mice with heterozygous Id4 mutant gene. By comparing to the control littermates with heterozygous TCL1 oncogene, mice with the loss of Id4 occur to have significantly accelerated CLL disease progression with shorter overall survival (12 versus 16 months, p-value<0.0001). The pathological analysis on Id4 mutant mice demonstrated that the CLL symptoms such as the elevated white blood cell counts, enlarged spleen and lymphoid tissues. We then performed the microarray studies on 1 month old TCL1 mice with control or mutant Id4 to identify ID4-dependent transcriptional changes in primary B-cells. Among the identified targets, genes involved in cell proliferation and anti-apoptosis were then verified. Supportively, B-cells from Id4 mutant TCL1 mice have significantly (p-value<0.001) diminished apoptosis in response to dexamethasone treatment. Additionally, both significant in vitro (p-value<0.001) and in vivo (p-value=0.025) increased proliferation of Id4 mutant TCL1 B-cells after the stimulation by CpG685NO168 was demonstrated. These data provide support that Id4 acts as tumor suppressor in transformed B-lymphocytes and is silenced through the process of methylation. The Effort to identify binding partners of Id4 in CLL cells and targeting its re-expression is warranted.

Novel FISH probes designed to detect IGK-MYC and IGL-MYC rearrangements in B-cell lineage malignancy identify a new breakpoint cluster region designated BVR2

Detection of translocations involving MYC at 8q24.1 in B-cell lineage malignancies (BCL) is important for diagnostic and prognostic purposes. However, routine detection of MYC translocations is often hampered by the wide variation in breakpoint location within the MYC region, particularly when a gene other than IGH, such as IGK or IGL, is involved. To address this issue, we developed and validated four fluorescence in situ hybridization (FISH) probes: two break apart probes to detect IGK and IGL translocations, and two dual-color, dual-fusion FISH (D-FISH) probes to detect IGK-MYC and IGL-MYC. MYC rearrangements (four IGK-MYC, 12 IGL-MYC and four unknown partner gene-MYC) were correctly identified in 20 of 20 archival BCL specimens known to have MYC rearrangements not involving IGH. Seven specimens, all of which lacked MYC rearrangements using a commercial IGH/MYC D-FISH probe, were found to have 8q24 breakpoints within a cluster region >350-645 kb 3' from MYC, provisionally designated as Burkitt variant rearrangement region 2 (BVR2). FISH is a useful ancillary tool in identifying MYC rearrangements. In light of the discovery of the distally located BVR2 breakpoint cluster region, it is important to use MYC FISH probes that cover a breakpoint region at least 1.0 Mb 3' of MYC.

Hairy cell leukemia: Treatment results and association with secondary malignancy

American Journal of HematologyVolume 48, Issue 4 p. 291-291 Letters and CorrespondenceFree Access Hairy cell leukemia: Treatment results and association with secondary malignancy Y. L. Kwong, Y. L. Kwong University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this authorR. Liang, R. Liang University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this authorE. Chiu, E. Chiu University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this authorD. W. Chan, D. W. Chan University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this authorT. K. Chan, T. K. Chan University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this author Y. L. Kwong, Y. L. Kwong University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this authorR. Liang, R. Liang University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this authorE. Chiu, E. Chiu University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this authorD. W. Chan, D. W. Chan University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this authorT. K. Chan, T. K. Chan University Department of Medicine, Queen Mary Hospital, Hong KongSearch for more papers by this author First published: April 1995 https://doi.org/10.1002/ajh.2830480421Citations: 3AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. References 1 Kwong YL, Wong KF, Chan LC, Liang RHS, Chan JKC, Wei D, Chiu EKW, Chu YC, Todd D, Chan TK: The spectrum of chronic lymphoproliferative disorders in Chinese people-an analysis of 64 cases. Cancer 74: 174– 181, 1994. 2 Liang R, Chan V, Chan TK, Wong T, Chiu E, Lie A, Todd D: Detection of immunoglobulin gene rearrangement in lymphoid malignancies of B-cell lineage by seminested polymerase chain reaction gene amplification. Am J Hematol 43: 24– 28, 1993. 3 Machii T, Tokumine Y, Inoue R, Kitani T: Predominance of a distinct subtype of hairy cell leukemia in Japan. Leukemia 7: 181– 186, 1993. 4 Filleul B, Delannoy A, Ferrant A, Zeenebergh A, Bosly A, Doven C: A single course of 2-chlorodeoxyadenosine (2-CdA) does not eradicate leukemic cells in hairy cell leukemia (HCL) Patients achieving complete remission. Blood 82(suppl): 142a, 1993. 5 Kampmeier P, Spielberger R, Dickstein J, Mick R, Golomb H, Vardiman JW: Increased incidence of secondary neoplasms in patients treated with interferon α 2b for hairy cell leukemia: A clinicopathologic assessment. Blood 83: 2931– 6, 1994. Citing Literature Volume48, Issue4April 1995Pages 291-291 ReferencesRelatedInformation

Non-Hodgkin's Lymphoma After Treatment of Hodgkin's Disease: Association with Epstein-Barr Virus

Non-Hodgkin's lymphoma occurs infrequently as a late complication of obscure cause after treatment of Hodgkin's disease. We investigated the possible role of Epstein-Barr virus in the pathogenesis of such secondary malignancies of B-cell lineage. Two patients, aged 25 and 43 years, developed high-grade non-Hodgkin's lymphomas 12 and 8 years after radiation therapy for Hodgkin's disease. Serologic profiles in these patients showed evidence of acute and past Epstein-Barr virus infections, respectively. Molecular hybridization analysis showed the presence of multiple cellular equivalents of virus genome in tumor specimens from each patient. Our findings suggest that Epstein-Barr virus may play an integral role in the pathogenesis of non-Hodgkin's lymphoma of B-cell lineage that develops after treatment of Hodgkin's disease.

Immunologic classification of lymphocytic leukemias based on monoclonal antibody-defined cell surface antigens

A panel of monoclonal antibodies reactive with normal lymphocyte subsets was used to classify cases of lymphocytic leukemia on the basis of cell surface antigen expression. The antibodies employed were commercially available and included a common framework HLA-DR antibody, two pan-T antibodies (Leu-1 and OKT-3), and antibodies defining cytotoxic/suppressor (Leu-2 and OKT-8) and helper/inducer (Leu-3 and OKT-4) subpopulations of normal T lymphocytes. Cases of ALL could be subgrouped into non-T non-B, pre-T and T-ALL on the basis of reactivity with HLA-DR, Leu-1, and OKT-3 antibodies. Leukemic cells from patients with T-cell CLL could be divided into Leu-2/OKT-8 reactive and Leu-3/OKT-4 reactive subpopulations, as well as a subgroup in which the majority of cells were unreactive with either of these antibodies. With the exception of one individual, all Sézary cell leukemias expressed a phenotypic pattern similar to that of the Leu-3 subgroup of T-CLL. Malignancies of B-cell lineage (B-CLL, prolymphocytic leukemia, and lymphosarcoma) that were examined were reactive with both the HLA-DR and Leu-1 antibodies. On the contrary, normal B lymphocytes and lymphoid cell lines of B-cell origin did not express surface antigens recognized by the Leu-1 antibody.

Immunologic classification of lymphocytic leukemias based on monoclonal antibody-defined cell surface antigens

A panel of monoclonal antibodies reactive with normal lymphocyte subsets was used to classify cases of lymphocytic leukemia on the basis of cell surface antigen expression. The antibodies employed were commercially available and included a common framework HLA-DR antibody, two pan-T antibodies (Leu-1 and OKT-3), and antibodies defining cytotoxic/suppressor (Leu-2 and OKT-8) and helper/inducer (Leu-3 and OKT-4) subpopulations of normal T lymphocytes. Cases of ALL could be subgrouped into non-T non-B, pre-T and T-ALL on the basis of reactivity with HLA-DR, Leu-1, and OKT-3 antibodies. Leukemic cells from patients with T-cell CLL could be divided into Leu-2/OKT-8 reactive and Leu- 3/OKT-4 reactive subpopulations, as well as a subgroup in which the majority of cells were unreactive with either of these antibodies. With the exception of one individual, all Sezary cell leukemias expressed a phenotypic pattern similar to that of the Leu-3 subgroup of T-CLL. Malignancies of B-cell lineage (B-CLL, prolymphocytic leukemia, and lymphosarcoma) that were examined were reactive with both the HLA-DR and Leu-1 antibodies. On the contrary, normal B lymphocytes and lymphoid cell lines of B-cell origin did not express surface antigens recognized by the Leu-1 antibody.