A phase I study of tipifarnib combined with conventional induction and consolidation therapy for previously untreated patients with acute myeloid leukemia aged 60 years and over.

Patients aged 60 years and over with previously untreated acute myeloid leukemia were enrolled in a Phase I study combining tipifarnib with standard induction therapy. The regimen consisted of cytarabine 100 mg/m(2)/day continuous intravenous (i.v.) infusion on days 1-7, daunorubicin 60 mg/m(2)/day i.v. push x 3 on days 6-8 and tipifarnib twice daily on days 6-15. Tipifarnib was escalated over four dose levels (200, 300, 400 and 600 mg). Patients achieving complete response (CR) were eligible to receive one consolidation using the same regimen. The following dose-limiting toxicities (DLTs) were identified during induction: dose level I: 2/6 (hyperbilirubinemia, respiratory arrest), level II: 0/3, level III: 0/3 and level IV: 4/10 (one each of diarrhea, neutropenic enterocolitis, arrhythmia and delayed hematologic recovery post-consolidation). There were no DLTs due to delayed hematologic recovery post-induction. Of 22 evaluable patients, there were 10 CR, 2 morphologic leukemia-free state (MLFS), 2 partial remission (PR) and 8 non-responders. Of seven patients with adverse risk cytogenetics, there were four CR/MLFS and one PR. In summary, this regimen was well tolerated and the maximum tolerated dose was not reached, although somewhat more severe gastrointestinal toxicity was seen at dose level IV. Tipifarnib 600 mg b.i.d. is considered the recommended dose for further study using this regimen.

Intravenous immunoglobulin as an adjunct to plasma exchange for the treatment of chronic thrombotic thrombocytopenic purpura.

Thrombotic thrombocytopenic purpura (TTP) is a life-threatening disease. Therapeutic plasma exchange (TPE) is the most effective therapy; however, despite TPE, about one-third of TTP patients will relapse. A subset of patients with TTP has antibodies to ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13) and may become resistant to conventional treatments. We describe a patient with TTP and high-titre anti-ADAMTS13 antibodies who developed a chronic, relapsing course of TTP despite frequent TPE. Once adjuvant treatment with intravenous immunoglobulin (IVIG) was added, remission was achieved. Even during remission, anti-ADAMTS13 antibodies remained elevated. We conclude that IVIG may sustain remission in some patients with chronic, relapsing TTP.

Retinoic acid modulation of induced basophil differentiation.

Current models of the regulation of hematopoiesis postulate a combination of both factor-directed cell differentiation/survival acting through intracellular signaling pathways, and factor-independent differentiation along intrinsically set, default pathways. Recent reports have indicated that eosinophil/basophil (Eo-Baso) differentiation may represent one default pathway. Because of the strong modulating effect of all trans-retinoic acid (ATRA) on hematopoietic differentiation, we have investigated the role of ATRA in regulating Eo-Baso differentiation from pluripotent progenitors. Our results indicate that ATRA inhibits Eo-Baso maturation at early stages of lineage commitment. Because allergic responses may depend on the continued recruitment and differentiation of such inflammatory mediators, the ability to modulate this pathway may eventually prove to have a therapeutic role in allergic inflammation.

Randomized phase II comparison of standard CHOP with weekly CHOP in elderly patients with non-Hodgkin's lymphoma.

PURPOSE: To determine whether modifying the standard regimen of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) from full doses given every 3 weeks to one-third doses given weekly (chop) increases the received chemotherapy dose-intensity in elderly patients with advanced-stage intermediate-grade lymphoma. PATIENTS AND METHODS: Consenting patients, age > or = 65 years who had acceptable cardiac, renal, and liver function and an Eastern Cooperative Oncology Group (ECOG) performance status less than 4, were stratified by bone marrow and performance status and randomized to receive standard CHOP or weekly chop. Drug doses were attenuated or escalated according to a defined dose-modification schedule. The primary outcome was average relative received dose-intensity. Secondary outcomes included response, progression-free and overall survival, toxicity, and performance status. RESULTS: Nineteen patients were allocated to each group. No difference in received dose-intensity was seen. When dose-intensity was calculated for the first six cycles of therapy, average relative received dose-intensity was .92 with CHOP versus .89 with weekly chop (P = .5); when calculated for the first 18 weeks of therapy, values were .88 with CHOP versus .89 with weekly chop (P = .8). The complete response rate was 68% with CHOP versus 74% with weekly chop (P = .9). At 2 years, the progression-free survival rate was 57% with CHOP versus 46% with weekly chop (P = .16) and the survival rate was 74% with CHOP versus 51% with weekly chop (p = .05). More myelotoxicity was seen with CHOP. CONCLUSION: We conclude that CHOP can be given in sufficient doses to elderly patients and that weekly chop does not increase received dose-intensity. Progression-free and overall survival are unlikely to be superior with weekly chop, and may be worse. CHOP should remain the standard against which new therapies for elderly patients with intermediate-grade lymphoma are compared.

B-cell lymphoma of recipient origin 9 years after allogeneic bone marrow transplantation for T-cell acute lymphoblastic leukaemia.

A 25-year-old woman developed an immunoblastic lymphoma 9 years after HLA-identical allogeneic bone marrow transplantation for T-cell acute lymphoblastic leukaemia in second remission. The B-cell origin of the second malignancy was confirmed by gene rearrangement studies. Despite continued donor engraftment, two separate genotypic analyses identified the lymphoma to be of recipient origin. This is the longest latency of a post-transplant recipient lymphoma yet reported and illustrates that recipient B-cells may survive the transplant conditioning regimen and undergo malignant transformation in the presence of donor haemopoiesis.

Rearrangement of TCR gamma chain gene involving JP1 suggests early thymocyte origin of peripheral T-cell lymphoma.

Peripheral T-cell lymphomas (PTL) are morphologically and immunophenotypically heterogeneous. We have examined a series of cases to determine whether this heterogeneity is reflected at the level of developmentally specific T-cell receptor (TCR) gene rearrangement. 4 of 5 cases had clonal rearrangements of TCR beta and gamma chain genes; one of these also had a probable DQ52-J immunoglobulin heavy chain gene rearrangement. 2 of the 4 TCR gamma gene rearrangements involved the most 5' J region, JP1, a characteristic of immature thymocytes. These 2 cases also had immunophenotypic features of immaturity. Taken together, our results suggest that TCR gene rearrangement is correlated with surface marker data and shows that in some cases PTL may arise from a very early stage of thymocyte maturation.

Characterization of Hodgkin's disease derived cell line HDLM-2.

The cell line HDLM-2 was established from the pleural effusion of a patient with Hodgkin's disease. Here, we describe the morphological, cytochemical, enzymological, immunological, molecular biological, and functional characteristics of the cell line. The results of this multiparameter profile show that HDLM-2 is different from other well-studied leukemia-lymphoma cell lines including other Hodgkin's disease derived cell lines. HDLM-2 cultures contain mainly mono- or binucleated cells, but also prominent giant cells with two to ten nuclei. HDLM-2 cells do not express an immunophenotype characteristic of a given cell lineage. However, the cells are positive for Ki-1, HeFi-1, Leu-M1, Tac, and HLA class II markers. Cytochemical, enzymological, and functional data are equally inconclusive, but are definitely not compatible with a monocyte/macrophage profile. Analysis of the gene status documents that T-cell receptor beta- and gamma-chain genes are rearranged while immunoglobulin heavy chain genes are in germline configuration. The combined results indicate a T-cell origin of HDLM-2 cells. The evidence available from this and other established Hodgkin's disease derived cell lines suggests a lymphoid origin of Hodgkin and Reed-Sternberg cells.

Abnormalities in T-cell associated rearrangement of T-cell receptor gamma chain genes in B-cell chronic lymphocytic leukemia.

Non-random rearrangement of genes encoding the gamma chain of the T-cell antigen receptor is known to occur in a developmentally regulated fashion during thymocyte differentiation. We show here that peripheral blood T lymphocytes from patients with B-cell chronic lymphocytic leukemia display marked abnormalities in the spectrum of gamma variable region gene rearrangements compared with normal peripheral blood. Of seven patients studied, all displayed a reduction of rearrangements into V9 (subgroup V II), while two cases had, in addition, over-representation of specific rearrangements involving subgroup V I; one V 2/4, the other V 5. These observations have a number of implications relevant to mechanisms of disease pathogenesis, and may provide new insight into the basis of T-cell dysfunction that is frequently associated with this condition.

T-cell receptor gene rearrangement in B-cell non-Hodgkin's lymphoma: correlation with methylation and expression.

Two of 19 B-cell non-Hodgkin's lymphoma (NHL) were found to have clonally rearranged T-cell receptor (TCR) beta chain genes with a germline TCR-gamma gene configuration. The inappropriate rearrangements had a similar structure to the TCR-beta rearrangements described in B-cell chronic lymphocytic leukemia. All cases analysed displayed a consistent germline transcription of TCR-beta and alpha chain genes which was independent of rearrangement. Consistent with this, all cases showed some degree of hypomethylation of the TCR-beta chain locus similar though distinguishable from the pattern seen in mature T cells, but quite different from that seen in normal mature B cells. Taken together, these data suggest that most NHL's arise from an immature B-lymphocyte precursor at a stage of differentiation where lineage commitment is incomplete.

Genotypes and immunophenotypes of Hodgkin's disease-derived cell lines.

This report describes the geno- and immunophenotypic analysis of the Hodgkin's disease-derived cell lines HDLM-2, KM-H2, and L-428. The lines were all positive for the antigens CD15 (Leu-M1), CD30 (Ki-1), Hefi-1 (antigen detected by a monoclonal antibody produced against L-428), HLA class I and II, and activation/proliferation markers. The cells from all 3 cell lines lacked almost all cell lineage-associated/specific markers: HDLM-2 was only CD2+, KM-H2 was only CD9+ and CD21+, and L-428 was negative for all the specific markers tested. Genomic analysis of HDLM-2 cells revealed monoclonal rearrangements of T cell receptor beta and gamma loci and germ line configuration of immunoglobulin genes. Immunoglobulin heavy chain genes were rearranged in KM-H2 and L-428. These data suggest a possible lymphoid origin for HDLM-2, KM-H2, and L-428. Although the data presented do not provide formal proof of a lymphoid nature of Hodgkin and Reed-Sternberg cells and do not unequivocally exclude a derivation from other hematopoietic cells, extrapolation of the results from the in vitro cultures to the in vivo situation suggests a lymphoid (T or B cell) origin of these cells.

Mixed acute leukaemias.

In recent years immunophenotyping and analysis of clonal rearrangement of immunoglobulin and T-cell antigen receptor genes have proved valuable for the diagnosis and classification of leukaemia. These techniques aid in the assignment of cell lineage in cases of acute leukaemia in which the standard FAB criteria of morphology and cytochemistry do not reveal clear lymphoid or myeloid phenotype. These new techniques have also revealed that the leukaemic blasts in a sizable minority of otherwise typical cases of acute leukaemia express 'inappropriate' lineage-associated markers and have been termed mixed acute leukaemias. The spectrum of characteristics encompassed by mixed acute leukaemias ranges from fairly common cases expressing one or two inappropriate markers to the more extreme, rare cases of acute leukaemia termed 'hybrid' in which a truly scrambled picture is seen. A subgroup of these mixed cases have two distinct populations of blasts, e.g. one lymphoid and the other myeloid. These observations raise a number of issues about the cell of origin of these leukaemias and about the mechanisms controlling the developmental regulation of expression of different lineage-associated markers. In addition, accumulating evidence suggests that inappropriate expression of markers may identify sub-groups of both acute myeloid and lymphoblastic leukaemia with an inferior prognosis.

Rearrangement and expression of T cell antigen receptor genes in B cell chronic lymphocytic leukemia.

Fifty-nine patients with B cell chronic lymphocytic leukemia (B-CLL) were screened for clonal rearrangement of T cell receptor (TCR) beta and gamma chain genes. Four were found with rearranged TCR beta genes, but none had detectable rearrangement of TCR gamma genes. One typical patient with B-CLL had a TCR beta gene structure consistent with a variable-diversity-joining rearrangement into the C beta 2 gene on one allele. An apparently identical rearrangement pattern was seen in a second patient, which suggested that there may be a restriction on the repertoire of possible TCR beta gene recombinations in mature B cells. Two further patients had a simple deletion of sequences, consistent with a diversity-joining rearrangement into C beta 2 on one allele. All four patients had rearrangements of immunoglobulin heavy- and light-chain genes typical of mature B cell malignancies. However, on review of clinical, morphological, and immunophenotype data, two had features consistent with B cell prolymphocytic leukemia or B lymphoma, and a third had progressed to a prolymphocytic transformation. Low-level expression of a predominantly 1.0- to 1.2-kilobase germ line TCR beta gene transcript was detected in several B-CLLs and at a comparable level in the four with rearranged TCR beta genes. This, together with the low frequency of TCR gene rearrangement, suggests that most B-CLL cases arise at a developmental stage when factors required for TCR gene activity are not operative.

Morphine analgesia and tolerance in the tail-flick and formalin tests: dose-response relationships.

The dose-response relationships for morphine analgesia were studied in morphine-tolerant and non-tolerant rats using two pain tests: the tail-flick test which measures the threshold for an escape response, and the formalin test which assesses the behavioral response to continuous pain generated in injured tissue. The effects of prior experience with both pain tests on tolerance were also examined. In the formalin test, effective analgesia was obtained in non-tolerant rats at doses that produce minimal depression of locomotor behavior. Morphine tolerance was produced by 20 daily injections of morphine with increments that reached 16 mg/kg, a dose over the LD100 for barrier sustained Long Evans rats. This dose regimen produced a 1.8-fold increase in the ED50 in the tail-flick test and a 2.7-fold increase in the formalin test. Daily experience of the pain test, as well as the morphine regimen produced a 4.8-fold increase in the ED50 in the tail-flick test but did not affect the potency of morphine in the formalin test. The magnitude of tolerance in the absence of daily behavioral testing is consistent with recent clinical reports that little tolerance occurs after prolonged administration of morphine in cancer patients and that tolerance is not an important consideration in the management of pain.