Treatment of sporadic Burkitt lymphoma in adults, a retrospective comparison of four treatment regimens.

Burkitt lymphoma is an aggressive B cell malignancy accounting for 1-2% of all adult lymphomas. Treatment with dose-intensive, multi-agent chemotherapy is effective but associated with considerable toxicity. In this observational study, we compared real-world efficacy, toxicity, and costs of four frequently employed treatment strategies for Burkitt lymphoma: the Lymphome Malins B (LMB), the Berlin-Frankfurt-Münster (BFM), the HOVON, and the CODOX-M/IVAC regimens. We collected data from 147 adult patients treated in eight referral centers. Following central pathology assessment, 105 of these cases were accepted as Burkitt lymphoma, resulting in the following treatment groups: LMB 36 patients, BFM 19 patients, HOVON 29 patients, and CODOX-M/IVAC 21 patients (median age 39 years, range 14-74; mean duration of follow-up 47 months). There was no significant difference between age, sex ratio, disease stage, or percentage HIV-positive patients between the treatment groups. Five-year progression-free survival (69%, p = 0.966) and 5-year overall survival (69%, p = 0.981) were comparable for all treatment groups. Treatment-related toxicity was also comparable with only hepatotoxicity seen more frequently in the CODOX/M-IVAC group (p = 0.004). Costs were determined by the number of rituximab gifts and the number of inpatients days. Overall, CODOX-M/IVAC had the most beneficial profile with regards to costs, treatment duration, and percentage of patients completing planned treatment. We conclude that the four treatment protocols for Burkitt lymphoma yield nearly identical results with regards to efficacy and safety but differ in treatment duration and costs. These differences may help guide future choice of treatment.

FADD expression is associated with regional and distant metastasis in squamous cell carcinoma of the head and neck.

AIMS: The Fas-associated death domain gene (FADD) is often overexpressed in squamous cell carcinoma of the head and neck (HNSCC), and is considered to be a driver gene in amplification of the chromosomal 11q13.3 region. Amplification of 11q13.3 is associated with increased metastasis in HNSCC and breast cancer. The aim of this study was to investigate the association between FADD protein expression in advanced-stage HNSCC and clinicopathological features and outcome. METHODS AND RESULTS: Tumour tissues of 177 HNSCC patients uniformly treated with primary surgery and postoperative radiotherapy were collected. FADD expression was assessed on pretreatment tumour biopsies using immunohistochemistry. High FADD expression was detected in 44% of the HNSCC patients. High expression was associated with an increased rate of lymph node metastasis (P = 0.001) and with a shorter distant metastasis-free interval (DMFI) (HR 2.6, 95% CI 1.0-6.7, P = 0.046) when lymph node metastases were present. CONCLUSIONS: Our data show that an increase in FADD expression is associated with a higher incidence of lymph node metastasis at presentation, and with shorter DMFI when lymph node metastases are present. High FADD expression in the primary tumour could be a useful marker to select patients for systemic treatment strategies that reduce the risk of distant metastases.

Tryptase and histamine metabolites as diagnostic indicators of indolent systemic mastocytosis without skin lesions.

BACKGROUND: Risk indicators of indolent systemic mastocytosis (ISM) in adults with clinical suspicion of ISM without accompanying skin lesions [urticaria pigmentosa (UP)] are lacking. This study aimed at creating a decision tree using clinical characteristics, serum tryptase, and the urinary histamine metabolites methylimidazole acetic acid (MIMA) and methylhistamine (MH) to select patients for bone marrow investigations to diagnose ISM. METHODS: Retrospective data analysis of all adults, in whom bone marrow investigations were performed to diagnose ISM, was carried out. RESULTS: In total, 142 patients were included. SM was absent in all 44 patients with tryptase <10 µg/l, in 45 of 98 (46%) patients with tryptase ≥10 µg/l and in 18 of 52 patients (35%) with tryptase >20 µg/l. Above 43 µg/l, all patients had ISM (n = 11). Male gender, insect venom anaphylaxis as presenting symptom, tryptase, MIMA, and MH were independent ISM predictors. If tryptase was ≥10 µg/l, the diagnostic accuracy of MIMA and MH was high (areas under the ROC curve 0.92). CONCLUSIONS: In suspected patients without UP, the ISM risk is very low (if present at all) if tryptase is <10 µg/l. If tryptase is ≥10 µg/l, this risk depends on MIMA and MH, being low if these are normal, but high if these are elevated. Male gender and insect venom anaphylaxis are additional risk indicators. We recommend refraining from bone marrow examinations in suspected patients without UP if tryptase is <10 µg/l. Our results question the reliability of the minor diagnostic World Health Organization criterion of tryptase >20 µg/l.

Translocation t(14;18) in B cell lymphomas as a cause for defective immunoglobulin production.

Although follicle center cell (FCC) lymphomas represent mature B cells, a considerable percentage do not have detectable Ig production. We have used Southern blotting and the polymerase chain reaction (PCR) to study the involvement of translocations t(14;18) and t(8;14) in causing defective Ig production in 16 Ig- FCC-derived lymphomas and three Ig- B cell acute lymphoblastic leukemias. In 6 of 19 cases, a t(14;18) was present with the other allele either deleted or in germline. In two cases a t(14;18) and a t(8;14) affected both Ig alleles, as confirmed by karyotyping. In two other cases, rearrangement of both bcl-2 on chromosome 18 and c-myc on chromosome 8 were found as well. Although cytogenetic proof was not available, the latter was probably involved in t(8;14). Restriction map analysis of one more case showed rearrangement on the pseudo-JH3 gene on one allele and t(14;18) on the other. Thus, in 11 of 19 cases, defective Ig H chain production could be explained by the inactivation of both Ig H chain genes due to translocation of one allele, in combination with deletions or defective rearrangements of the other allele. In contrast, in 28 of 30 Ig+ lymphomas, one functional Ig H chain allele was found, either in, or not in, combination with t(14;18). In two cases a single rearranged Ig H chain allele was found in combination with rearrangement of bcl-2. No comigration of the single Ig rearrangement with bcl-2, however, was found both by Southern blotting and PCR, suggesting a variant bcl-2 translocation, which leaves the Ig H chain allele functionally intact.

A super-SILAC based proteomics analysis of diffuse large B-cell lymphoma-NOS patient samples to identify new proteins that discriminate GCB and non-GCB lymphomas.

Diffuse large B-cell lymphoma-not otherwise specified (DLBCL-NOS) is a large and heterogeneous subgroup of non-Hodgkin lymphoma. DLBCL can be subdivided into germinal centre B-cell like (GCB) and activated B-cell like (ABC or non-GCB) using a gene-expression based or an immunohistochemical approach. In this study we aimed to identify additional proteins that are differentially expressed between GCB and non-GCB DLBCL. A reference super-SILAC mix, including proteins of eight B-cell lymphoma cell lines, was mixed with proteins isolated from seven non-GCB DLBCL and five GCB DLBCL patient tissue samples to quantify protein levels. Protein identification and quantification was performed by LC-MS. We identified a total of 4289 proteins, with a four-fold significant difference in expression between non-GCB and GCB DLBCL for 37 proteins. Four proteins were selected for validation in the same cases and replication in an independent cohort of 47 DLBCL patients by immunohistochemistry. In the validation cohort, we observed a non-significant trend towards the same differential expression pattern as observed in the proteomics. The replication study showed significant and consistent differences for two of the proteins: expression of glomulin (GLMN) was higher in GCB DLBCL, while expression of ribosomal protein L23 (RPL23) was higher in non-GCB DLBCL. These proteins are functionally linked to important pathways involving MYC, p53 and angiogenesis. In summary, we showed increased expression of RPL23 and decreased expression of GLMN in non-GCB compared to GCB DLBCL on purified primary DLBCL patient samples and replicated these results in an independent patient cohort.

Overexpression of intrinsic hypoxia markers HIF1alpha and CA-IX predict for local recurrence in stage T1-T2 glottic laryngeal carcinoma treated with radiotherapy.

PURPOSE: To examine the prognostic value of three endogenous hypoxia markers (hypoxia inducible factor 1 alpha subunit [HIF1 alpha], carbonic anhydrase IX [CA-IX], and glucose transporter type 1 [GLUT-1]) on the clinical outcome in patients with early-stage glottic carcinoma primarily treated with radiotherapy (RT) and to determine the predictive hypoxic profile to choose the optimal treatment of early-stage laryngeal carcinoma. METHODS AND MATERIALS: Immunohistochemistry for HIF1 alpha, CA-IX, and GLUT-1 was performed on formalin-fixed, paraffin-embedded, pretreatment tissue samples of 91 glottic squamous cell carcinoma specimens. The patient group consisted only of those with early-stage (T1-T2) glottic carcinoma, and all patients were treated with RT only. Relative tumor staining was scored on the tissue samples. Receiver operating curve analysis was performed to determine the optimal cutoff value for each tumor marker. Cox regression analyses for the variables HIF1 alpha, CA-IX, GLUT-1, gender, age, hemoglobin level, T category, N category, tobacco use, and alcohol use were performed with local control and overall survival as endpoints. RESULTS: HIF1 alpha overexpression in early-stage glottic carcinoma correlated significantly with worse local control (hazard ratio [HR], 3.05; p = 0.021) and overall survival (HR, 2.92; p = 0.016). CA-IX overexpression correlated significantly with worse local control (HR, 2.93; p = 0.020). GLUT-1 overexpression did not show any correlation with the clinical outcome parameters. Tumors with a nonhypoxic profile (defined as low HIF1 alpha and low CA-IX expression) had significantly better local control (HR, 6.32; p = 0.013). CONCLUSION: The results of our study have shown that early-stage glottic laryngeal carcinomas with low HIF1 alpha and CA-IX expression are highly curable with RT. For this group, RT is a good treatment option. For tumors with HIF1 alpha or CA-IX overexpression, hypoxic modification before RT or primary surgical treatment should be considered.

Malignant aldosterone-producing adrenal tumour: reoccurrence with glucocorticoid excess without hyperaldosteronism.

We describe a case of hypokalaemic hypertension due to hyperaldosteronism caused by a unilateral adrenocortical tumour with unfavourable histopathology suggestive of malignancy. After removal, the aldosterone excess disappeared. The patient's clinical course was uneventful, until she presented with extensive metastases of adrenal carcinoma four years later. Biochemical abnormalities were now consistent with glucocorticoid excess without hyperaldosteronism. She died four months later. Although malignant aldosterone-producing adrenal tumours are very rare, the present case underscores that clinicians should be aware that primary hyperaldosteronism can occur in the context of adrenocortical carcinoma.

Short intensive sequential therapy followed by autologous stem cell transplantation in adult Burkitt, Burkitt-like and lymphoblastic lymphoma.

The feasibility and efficacy of up-front high-dose sequential chemotherapy followed by autologous stem cell transplantation (ASCT) in previously untreated adults (median age 33 years; range 15-64) with Burkitt lymphoma (BL), Burkitt-like lymphoma (BLL) or lymphoblastic lymphoma (LyLy), both without central nervous system or extensive bone marrow involvement was investigated in a multicenter phase II study. Treatment consisted of two sequential high-dose chemotherapy induction courses incorporating prednisone, cyclophosphamide, doxorubicin, etoposide and mitoxantrone, without high-dose methotrexate or high-dose cytarabine. Patients with at least PR went on with BEAM and ASCT. Protocol treatment was completed by 23/27 (85%) BL/BLL and 13/15 (87%) LyLy patients. Median treatment duration until BEAM was 70 (range: 50-116) days. No toxic deaths occurred. Response to treatment was complete response (CR) 81% and partial response (PR) 11% for BL/BLL, CR 73% and PR 20% for LyLy. At a median follow-up of 61 months of patients still alive, six BL/BLL and eight LyLy patients have died. The actuarial 5-year overall and event-free survival estimates are 81 and 73% for BL/BLL vs 46 and 40% for LyLy patients. In conclusion, this short up-front high-dose sequential chemotherapy regimen, followed by ASCT is highly effective in adults with BL/BLL with limited bone marrow involvement, but less so in patients with LyLy.

Multiple breakpoints within the BCL-1 locus in B-cell lymphoma: rearrangements of the cyclin D1 gene.

Centrocytic lymphoma (CC) and intermediately differentiated lymphocytic lymphoma (IDL) are B-cell non-Hodgkin's lymphomas composed of lymphocytes presumably derived from follicle mantle cells. In these lymphomas, a specific chromosomal translocation, t(11;14)(q13;q32), has been described. Previous studies suggested an association between t(11;14) chromosomal translocations and BCL-1 rearrangements. To evaluate the association between BCL-1 rearrangements and CC/IDL, Southern blot analysis was performed on a panel of 20 cases of CC/IDL, 22 cases of morphologically similar non-Hodgkin's lymphomas, 11 cases of chronic B-cell leukemias, and 2 cases of myelomas. We used various probes covering a considerable proportion of the 120-kilobase BCL-1 locus, and rearrangements in 50% of CC/IDL (10 of 20) were detected. In CC, all 4 breakpoints were located at the major translocation cluster (MTC). In contrast, in IDL, rearrangements were detected in 3 different cluster regions: 2 cases in the MTC, 2 cases with a breakpoint 24 kilobases outside the MTC, and 2 additional cases with breakpoints found 3 kilobases 5' of the first exon of the PRAD1/CCND1 gene, which is located 120 kilobases outside the MTC. In addition, one leukemia showed a breakpoint 63 kilobases outside the MTC. In all cases, there was comigration of the rearranged 11q13 fragment and the immunoglobulin heavy chain-joining gene complex, indicating a t(11;14)(q13;q32) chromosomal rearrangement. Our results show that Southern blot analysis is helpful to identify CC/IDL, but multiple breakpoints are present over a large region, and therefore, many probes are necessary to cover all breakpoints.

Subcellular localization of the bcl-2 protein in malignant and normal lymphoid cells.

The bcl-2 oncogene is expressed in lymphoid and myeloid cells as well as in neurons and several types of epithelial cells and inhibits programmed cell death (apoptosis). Deregulation by the t(14;18) translocation in lymphoid malignancies induces inappropriate cell survival and serves as one of the steps toward a fully malignant behavior. Using pre- and postembedding immunoelectron microscopy in normal and neoplastic lymphocytes, we demonstrate bcl-2 immunoreactivity to the mitochondrial outer circumference and the nuclear envelope and to a lesser degree to the cell membrane. Mitochondrial staining was patchy, reminiscent of mitochondrial contact zones. Additionally, there was a suggestion of association with nuclear pores. In these regions, transmembrane transport is mediated. This may suggest that bcl-2 exerts its function in this process.

Cyclin D1 messenger RNA overexpression as a marker for mantle cell lymphoma.

In mantle cell lymphoma (MCL) a recurrent chromosomal rearrangement, t(11;14)(q13;q32), has been described. Most breakpoints have been detected within the 120 kb BCL-1 region, upstream of the cyclin D1 gene. To evaluate the association between BCL-1 rearrangement and expression of cyclin D1 in lymphoproliferative disorders, we analysed a series of 24 MCL, 56 other B-cell non-Hodgkin's lymphomas (NHL), 28 chronic B-cell leukemias, 18 hematopoietic cell lines and 10 normal lymphoid tissues at the RNA level. Hematopoietic cell lines with a known 11q13 translocation showed high expression of the 4.5 kb cyclin D1 transcript. Three B-cell lines without known 11q13 breakpoint showed low expression. We detected high expression in all (11/11) MCL with and in 11 out of 13 cases of MCL without detectable t(11;14) rearrangement. In three cases with a rearrangement at the 3' end of cyclin D1, two showed overexpression of the 1.5 kb transcript and one expression of an aberrant (3.0 kb) transcript. In other lymphoproliferative disorders, only 5/15 hairy cell leukemias, all without detectable t(11;14), and 5/8 B-cell leukemias suspected to be MCL in leukemic phase showed expression levels comparable to MCL, whereas no or only low expression were observed in 56 cases of other NHL, seven chronic B-cell leukemias and all (10/10) normal lymphoid tissues. Cell sorting experiments on fresh tonsils showed that this low expression was present in normal B-cells and not in T-cells. In contrast to other studies, our data indicate that cyclin D1 is expressed in many lymphoproliferative disorders and normal tissues, albeit at low levels. High levels of expression of cyclin D1 however is restricted to MCL and some hairy cell leukemias. We therefore propose that overexpression of cyclin D1 is a reliable marker for the classification of MCL.

Bcl-2/JH rearrangements in benign lymphoid tissues with follicular hyperplasia.

The t(14; 18)(q32;q21) chromosomal translocation, characteristic of follicular lymphoma, couples the bcl-2 protooncogene on chromosome 18 to the immunoglobulin heavy-chain joining region (JH). This results in a deregulated transcription rate of bcl-2, suggesting a major role of the t(14;18) translocation in lymphomagenesis. By using a sensitive polymerase chain reaction technique specific for the major breakpoint region t(14;18), we now demonstrate the presence of bcl-2/JH rearrangements in lymph nodes and tonsils with follicular hyperplasia in 13 of 24 cases (54%). The approximate frequency was one translocation-positive cell in 10(5) cells. No bcl-2/JH rearrangements were detected in reactive lymph nodes without follicular hyperplasia or in bone marrow cells. Sequence analysis showed the amplified bcl-2/JH fragments to be unique to each individual sample and distinct from 24 sequenced follicular lymphoma-derived t(14;18) junctions, thus excluding contamination artifacts. The presence of random nucleotide insertions at the breakpoint junctions suggests a pre-B-cell origin of the t(14;18) translocation, in analogy with follicular lymphomas. We conclude that the t(14;18) translocation can occur in non-malignant tissue and will not, on its own, lead to malignancy.

Visualization of mono-allelic chromosomal aberrations 3' and 5' of the cyclin D1 gene in mantle cell lymphoma using DNA fiber fluorescence in situ hybridization.

In mantle cell lymphoma (MCL), in addition to the characteristic t(11;14)(q13;q32), rearrangements on the 3' side of the cyclin D1 gene have been described. In a series of 32 MCL we found three cases with 3'-rearrangements by Southern blot analysis with a probe representing the 3' untranslated region of the cyclin D1 gene. All three were characterized by the absence of the 4.5 kb transcript, and instead, two cases showed overexpression of the 1.7 kb and a third case (MCLp14) an aberrant 2.5 kb transcript. At the genomic level, fine mapping experiments showed in the 3' untranslated region a 2 kb deletion in MCLp14 and a breakpoint in the other two cases. Fiber FISH analysis showed that in all three cases the 3' aberration co-exists with a regular t(11;14) breakpoint 5' of cyclin D1 on a single allele. Fiber FISH analysis of 16 additional MCL revealed two other such cases with breakpoints 5' and 3' of cyclin D1. These mono-allelic aberrations affecting the cyclin D1 gene suggest that the t(11;14) as a first step switches on transcription, and then sequences in the untranslated region of cyclin D1 are affected to stabilize the message.

bcl-2 protein expression in primary cutaneous large B-cell lymphoma is site-related.

PURPOSE: Primary cutaneous large B-cell lymphoma (PCLBCL) that presents on the leg has recently been recognized as a distinct disease entity. These lymphomas have a reduced disease-free survival and a worse prognosis as compared with the more common, morphologically similar PCLBCL that present on the head or trunk. Studies in noncutaneous diffuse large B-cell lymphomas suggest a relationship between the expression of bcl-2 protein and clinical behavior. In the present study, we investigated whether these two groups of PCLBCL differ in the expression of bcl-2 protein and the presence of t(4;18), known as one of the causes of bcl-2 overexpression. PATIENTS AND METHODS: Paraffin sections from pretreatment biopsies of 14 PCLBCLs of the head or trunk and nine PCLBCLs of the legs were investigated for expression of bcl-2 protein using immunohistochemistry, and for the presence of the 14;18 translocation using polymerase chain reaction (PCR) amplification with primers against both the major breakpoint region (mbr) and the minor cluster region (mcr) of bcl-2. For reasons of comparison, nine secondary cutaneous large B-cell lymphomas (SCLBCLs) were also studied. RESULTS: Expression of bcl-2 protein was found in all nine PCLBCLs of the leg and in all nine SCLBCLs, but not in any of the 14 PCLBCLs on the head and trunk. The t(14;18) was only detected in two of seven SCLBCLs, but not in the five PCLBCLs of the leg or the eight PCLBCLs on the head or trunk studied. CONCLUSION: The striking differences in bcl-2 expression between PCLBCL of the head or trunk and PCLBCL on the leg suggest that bcl-2 expression is site-related and may contribute to the different clinical behavior between these two groups of lymphomas. In addition, they underscore that PCLBCL on the head and trunk and PCLBCL on the leg are distinct disease entities, as recently recognized in the European Organization for Research and Treatment of Cancer (EORTC) classification for primary cutaneous lymphomas.

Clinical significance of bcl2 and p53 protein expression in diffuse large B-cell lymphoma: a population-based study.

PURPOSE: We studied the prognostic significance of bcl2 and p53 protein expression in relation to clinical and pathologic characteristics in patients with diffuse large B-cell lymphoma (LCL). PATIENTS AND METHODS: Three hundred seventy-two patients with LCL were retrieved from a population-based registry for non-Hodgkin's lymphoma (NHL). bcl2 and p53 protein expression was studied on paraffin-embedded tumor tissue by immunohistochemistry in relation to clinical factors. Response to therapy and survival were analyzed in 165 patients who were uniformly staged and treated and for whom all prognostic data were available according to the International Prognostic Index (IPI). RESULTS: Forty-five percent of tumors showed strong expression of the bcl2 protein (bcl2++), with a higher frequency in patients with primary nodal involvement. Disease-free survival (DFS) was significantly better in bcl2-negative/intermediate (bcl2-/+) cases as compared with bcl2++ cases (P = .0011). At 5 years, bcl2-/+ patients showed a DFS rate of 74%, in contrast to bcl2++ patients with a DFS rate of 41% (P = .002). Bcl2 was the strongest independent prognostic value in a multivariate analysis, with a relative risk (RR) of 3.0 in comparison to p53 expression and the clinical factors of the IPI. Overall survival (OS) was not significantly influenced by bcl2 protein expression. p53 protein expression was found in 13% of cases, with a higher frequency in patients with extensive disease. p53 expression did not influence the chance to achieve complete remission (CR) and survival. CONCLUSION: bcl2 protein is frequently expressed in LCL and is a strong independent prognostic factor for DFS. p53 expression is related with high tumor burden, but is not an independent risk factor for CR and survival.

Mantle-cell lymphoma: a population-based clinical study.

PURPOSE: From a population-based non-Hodgkin's lymphoma (NHL) registry, 41 patients with mantle cell lymphoma (MCL) -- a recently defined distinct B-cell NHL -- were selected and compared with patients with low- or intermediate-grade NHL from the same registry. PATIENTS AND METHODS: The incidence and behavior of MCL in the area of the Comprehensive Cancer Center West (CCCW) from 1981 to 1989 were analyzed. Age, performance, tumor bulk, extranodal localization, stage, response to therapy, and survival were registered. Expression of cyclin D1 protein and Ki-67 were measured in 29 patients. RESULTS: MCL made up 3.7% of NHLs. The median age was 68 years, and the male-to-female ratio was 1.6:1. Seventy-eight percent presented with stage IV, with the majority having bone marrow involvement. The complete response (CR) rate was 32% (13 of 41), with a median duration of 25 months. The median overall survival time was 31.5 months. The International Prognostic Index identified five patients with a low-risk score and a median survival time of 93+ months. In 23 of 29 patients, cyclin D1 overexpression was present, without any relation to overall or disease-free survival. In contrast, a proliferative index less than 10% was significantly related to a better overall survival time (50 v 24 months). CONCLUSION: MCL is a disease of the elderly, who present with widespread disease and with a poor response to therapy. Although it harbors features of an indolent NHL, it behaves clinically as an aggressive NHL with a short overall survival time.

Homing and antigenic characterization of a human non-Hodgkin's lymphoma B cell line in severe combined immunodeficient (SCID) mice.

The dissemination pattern of a human non-Hodgkin's lymphoma (NHL) B cell line (DoHH2) carrying the t(14;18) translocation was analyzed in severe combined immunodeficient (SCID) mice, using different routes of administration. When engrafted intraperitoneally (i.p.) the DoHH2 cells showed a local infiltration into intra- and retroperitoneal mouse tissues, and disseminated to bone marrow and lymph nodes. In contrast, after subcutaneous (s.c.) or intravenous (i.v.) transfer the DoHH2 cells displayed a hematogenous spread, and disseminated predominantly to hematopoietic and lymphoid organs including bone marrow, peripheral blood, spleen, peripheral lymph nodes, and liver. No involvement of the gut and mesenteric lymph nodes was observed, suggesting a specific homing pattern, bypassing the mucosa-associated lymphoid tissue (MALT). This pattern is reminiscent of the human disease. Phenotypic analysis, cytogenetic analysis, and minor histocompatibility antigen (mHA) typing using mHA-specific cytotoxic T-lymphocyte (CTL) clones performed on the original DoHH2 cell line and on DoHH2 cells recovered from mouse tissue, showed that in vivo passage did not alter the characteristics of the DoHH2 cells. After i.v. administration, the survival time of the SCID mice directly correlated with the number of DoHH2 cells inoculated. This model of dissemination of the DoHH2 cell line may be useful for studying the efficacy of (immunotherapeutic) treatment of human lymphoproliferative disorders in vivo.

Circulating buttock cells in non-Hodgkin's lymphoma.

Leukemic B cells with a characteristically sharp nuclear cleft seemingly dividing the nucleus into two or more parts have been entitled "buttock cells" and are subject of this study. These cells were found in leukemic non-Hodgkin's lymphomas (NHL) and usually have been related to follicular center cell lymphomas. However, buttock cells also closely resemble cells present in intermediate lymphocytic lymphoma (ILL) and mantle zone cells of reactive lymphoid tissues. Ultrastructurally, it became apparent that the separate nuclear lobes of buttock cells were connected by chromatin bridges. Immunophenotypically, circulating buttock cells had a variable phenotype, which may indicate either a follicle center or mantle zone origin. The use of CD5 and FMC7 monoclonal antibodies might be of discriminative help. These leukemic NHL have to be differentiated from classical chronic lymphocytic leukemia (CLL) with help of cytomorphology and immunophenotyping, since the former usually have a worse prognosis and generally will require a different treatment.

A new non-Hodgkin's B-cell line (DoHH2) with a chromosomal translocation t(14;18)(q32;q21).

A spontaneously growing EBV-negative B-cell line (DoHH2) was established from the pleural fluid cells of a 60-year-old man with centroblastic/centrocytic non-Hodgkin's lymphoma, that had transformed into an immunoblastic lymphoma. The pleural fluid cells and the DoHH2 cells expressed IgG lambda, were reactive with CD10 and CD19 monoclonal antibodies, and showed by cytogenetic analysis 48,XY, +7, +del(12)(q24), t(14;18)(q32;q21). Southern blot analysis of mini-satellite DNA patterns, and of rearrangements of the immunoglobulin genes and bcl-2, confirmed that the cell line was derived from the patient's clonal lymphoma cells. Direct nucleotide sequence analysis on polymerase chain reaction (PCR) products of the t(14;18) junction revealed an identical sequence for the JH-bcl-2 junction at JH6 and in the major breakpoint region of bcl-2 in both the original tumor cells and the DoHH2 cell line. The cell line was valuable as a standard quantification control for PCR analysis of the t(14;18) breakpoint. Titration experiments demonstrated the detection of up to one tumor cell in 10(5) normal blood lymphocytes.