PubMed Health⌕ Search

Biomedical subjects

D H Boldt

Publications and source records attributed to D H Boldt.

At least 37 records · Page 2Linked to original sources
PubMed1994

Detection of BCR-ABL fusion genes in adult acute lymphoblastic leukemia by the polymerase chain reaction.

The sensitivity and clinical utility of the polymerase chain reaction (PCR) assay for the detection of BCR-ABL gene rearrangement was compared to conventional cytogenetics for the Philadelphia chromosome (Ph1) in adult acute lymphoblastic leukemia (ALL) patients entered onto a single clinical trial. Ninety-three patients had evaluable PCR assays for both the p190bcr-abl and p210bcr-abl type of BCR-ABL gene rearrangements. Twenty-one of 93 patients (23%) were positive for the BCR-ABL rearrangement by the PCR assay. Fourteen of these patients had the p210brc-abl BCR-ABL rearrangement characteristically seen in CML patients, while seven had the p190bcr-abl rearrangement seen in ALL alone. Of 61 patients analyzed, both with conventional cytogenetics and PCR, eight (13%) were positive for the Ph1, while 14 (23%) were positive for the BCR-ABL rearrangement by the PCR assay. Discordance between the PCR assay and cytogenetics occurred in eight cases where the PCR assay was positive and the cytogenetics negative, and two cases where the PCR assay was negative and cytogenetics positive. PCR positivity did not correlate with treatment response, survival, or relapse-free survival, but there was a higher percentage of L2 FAB morphology in the PCR+ cases compared to the PCR-cases (67 vs. 28%, p = 0.003). In addition, the data suggested that patients with a p190bcr-abl rearrangement have a better response to induction therapy, but a worse relapse-free survival compared to patients with a p210bcr-abl breakpoint, but these differences were not statistically significant. These data suggest that PCR and conventional cytogenetics may provide complementary information, since there appear to be a subset of patients who are Ph1-negative yet BCR-ABL positive by PCR. Further studies will be required to determine the prognostic significance of the detailed information about BCR-ABL breakpoints that is available from the PCR assay.

Adolescent↗
PubMed1993

Phase I trial of a 90-minute infusion of the fusion toxin DAB486IL-2 in hematological cancers.

DAB486IL-2, a recombinant fusion toxin in which the native receptor binding domain of diphtheria toxin has been replaced with interleukin-2 (IL-2), has displayed significant activity in patients with chemotherapy refractory hematological cancers. To further investigate the safety and antitumor effect of this agent, we conducted a single arm, dose escalation study of a 90-min infusion of DAB486IL-2 daily for 5 days. Patients with cancers of a histology previously reported to express the p55 component of the IL-2 receptor and who could not receive potentially more effective therapy were eligible for enrollment. Fifteen men and 8 women with a median age of 49 years were given a total of 51 courses of DAB486IL-2. The maximum tolerated dose was 0.3 mg/kg/day defined by renal insufficiency associated with hemolysis and thrombocytopenia. The clearance of DAB486IL-2 from serum fit a one-compartment model with a half-life of 11.5 +/- 4.3 (SD) min at the 0.2-mg/kg dose. Two patients sustained a partial response and 4 patients had tumor reduction not qualifying for an objective response. No tumors that were negative for expression of the p55 subunit of the receptor responded to DAB486IL-2 treatment. Reduction in size occurred in 2 tumors in which p55 expression was unknown and 4 patients with tumors that were known to be p55 positive. Dosing determined by specific activity rather than mass also appeared to be an important determinant of response. This study suggests that the presence of p55 expression on tumor cells is necessary, but alone may not be sufficient to achieve a tumor response. The correlation of additional variables such as specific activity of DAB486IL-2 and tumor expression of the p75 subunit of the IL-2 receptor and receptor function will also require further study.

Adult↗
PubMed1993

Phase IB clinical trial of anti-CD3 followed by high-dose bolus interleukin-2 in patients with metastatic melanoma and advanced renal cell carcinoma: clinical and immunologic effects.

PURPOSE: To determine the maximum-tolerated dose (MTD) of an anti-CD3 antibody, OKT3, in combination with high-dose interleukin-2 (IL-2), and to determine whether OKT3 can enhance the expansion of CD3+, CD25+ (IL-2 receptor alpha [IL-2R alpha])-expressing T cells in the peripheral blood of patients with advanced melanoma and renal cell carcinoma receiving high-dose IL-2. PATIENTS AND METHODS: We performed a phase IB trial of a murine monoclonal anti-CD3 antibody (OKT3) with high-dose IL-2 in patients with advanced melanoma and renal cell carcinoma. Fifty-four patients were enrolled, with cohorts of 10 or more patients receiving escalating doses of OKT3 at 75, 200, 400, and 600 micrograms/m2 on day 1 followed by IL-2 at an initial dose 0.45 and then 1.33 mg/m2 every 8 hours on days 2 through 6 and 16 through 20 (maximum, 28 doses). An additional cohort of 14 patients received high-dose IL-2 (1.33 mg/m2 per dose) alone. Circulating CD3+, CD25+ cells were monitored before therapy and following the initial week of IL-2. RESULTS: A total of 68 patients were enrolled. The MTD for OKT3 was defined as 400 micrograms/m2 based on a reduction in the number of IL-2 doses that could be administered. Increases in CD3+, CD25+ cells were observed within all cohorts; however, the increase was not OKT3 dose-dependent. On the other hand, we found that 60% (nine of 15) of patients tested at OKT3 dose levels of 200, 400, and 600 micrograms/m2 had increases in serum sCD25 (soluble IL-2R alpha) to more than 100,000 U/mL, while none of 10 patients who received IL-2 alone or with OKT3 at the 75-micrograms dose had increases greater than 60,000 U/mL. Of 29 patients with renal cell carcinoma who received OKT3 with IL-2 (1.33 mg/m2), there were three objective tumor responses (all partial responses). In the 16 patients with melanoma who received OKT3 plus IL-2, there was a single objective response (complete response). CONCLUSION: The doses of OKT3 administered on this schedule failed to enhance significantly the number of circulating CD3+, CD25+ T cells and did not appear to increase the antitumor activity of IL-2 alone, which underscores the need for other approaches to enhance the efficacy of IL-2 therapy.

Adult↗
PubMed1993

Comparison of engraftment and acute GVHD in patients undergoing cryopreserved or fresh allogeneic BMT.

Coordination of marrow donation for allogeneic BMT is a common logistical problem. The use of cryopreserved donor marrow would facilitate scheduling and avoid potential problems due to donor employment, injury, infection or death. We analysed results of 10 matched related BMTs performed with cryopreserved donor marrow and compared them with 33 matched related BMTs using fresh bone marrow over a 4 year period. No difference in time to engraftment of granulocytes and platelets or transfusion requirements were demonstrated for the two groups. However, there was less GVHD in patients who received cryopreserved donor marrow (chi 2, p = 0.03; Fisher's exact test (two-sided) p = 0.067) despite comparable risk factors. The reason for this difference is unclear. Our results indicate that the use of cryopreserved bone marrow for allogeneic BMT patients is at least equivalent to the use of fresh bone marrow. A prospective randomized trial is needed to determine if a true difference exists in the incidence or severity of acute GVHD and to determine if recurrence rate is different between the two groups.

Acute Disease↗
PubMed1992

A randomized phase II trial of continuous infusion interleukin-2 or bolus injection interleukin-2 plus lymphokine-activated killer cells for advanced renal cell carcinoma.

PURPOSE: Since 1985, multiple centers have demonstrated that interleukin-2 (IL-2) and lymphokine-activated killer (LAK) cells produce durable anticancer responses in patients with metastatic renal cell carcinoma. High-dose recombinant IL-2 (rIL-2) has been administered by intravenous bolus injection (Rosenberg SA, et al: N Engl J Med 313:1485-1492, 1985) and by continuous intravenous infusion (West WH, et al: N Engl J Med 316:898-905, 1987) combined with lymphokine-activated killer (LAK) cells, with both methods producing responses in patients with advanced renal cell carcinoma. The Extramural IL-2/LAK Working Group has conducted a randomized phase II trial of two intravenous high-dose rIL-2 regimens (bolus three times daily or 24-hour continuous infusion) to determine if either one manifests greater anticancer activity or a more acceptable toxicity profile. PATIENTS AND METHODS: Ninety-four patients with measurable advanced renal cell carcinoma were enrolled on this study: 46 to the bolus injection arm and 48 to the continuous infusion arm. On both arms, patients underwent a priming phase of rIL-2 administration, four daily lymphocytaphereses to harvest mononuclear cells that were placed in 3- to 4-day culture for generation of LAK cells, and an rIL-2/LAK coadministration phase. Patients were then observed monthly for evidence of response to this therapy and were offered up to two additional courses of treatment every 3 months if evidence of response was detected. RESULTS: Twenty percent of patients on the bolus injection arm experienced objective responses (three complete responses and six partial responses); 15% of patients on the continuous infusion arm responded (two complete responses and five partial responses). Complete responses were durable, persisting for 310+ to 700+ days. The incidence of severe life-threatening toxicities typical of high-dose rIL-2 therapy was similar in both arms (eg, patients with hypotension requiring pressors: bolus 71%, continuous 63%; oliguria less than or equal to 200 mL/8 hours: bolus 65%, continuous 71%). More episodes of fever, infection, and serum alkaline phosphatase elevation were associated with the continuous infusion arm, while more thrombocytopenia occurred on the bolus injection arm. Four patients (three bolus injection, one continuous infusion) died of respiratory and circulatory failure while under treatment. No clinical or laboratory parameter accompanying treatment on either arm was, by univariate or multivariate analysis, associated with an increased likelihood of response. CONCLUSIONS: Both methods of high-dose rIL-2/LAK cell administration produce nearly equivalent anticancer activity and toxicity in the treatment of renal cell carcinoma. The ability to predict responding patients based on patient or treatment characteristics is not possible.

Adolescent↗
PubMed1991

Induction of protein kinase C mRNA in cultured lymphoblastoid T cells by iron-transferrin but not by soluble iron.

Iron-transferrin (FeTF) is an essential growth factor required for proliferation of lymphoid cells. FeTF activates protein kinase C (PKC) in the lymphoblastoid T-cell line, CCRF-CEM. We have treated CEM cells with human FeTF, then examined levels of PKC mRNA by hybridization analysis using cDNA probes specific for alpha-, beta-, and gamma-PKC subspecies. CEM cell mRNA hybridized with the beta-subspecies probe but not with probes for alpha- or gamma-subspecies. After exposure to FeTF an increase in PKC-beta mRNA was detectable at 10 minutes, peaked at 12 hours, and was sustained for 72 hours. Nuclear transcription assays demonstrated that rates of PKC-beta mRNA transcription were increased in FeTF-treated cells. By contrast, steady state levels of PKC-beta mRNA did not increase after treatment of cells with apotransferrin or gallium TF. Similarly, treatment with soluble iron as ferric ammonium citrate did not increase steady state levels of PKC-beta mRNA, despite producing a marked increase in cellular ferritin content. Ferritin increased from a baseline value of 63 ng/10(6) cells to 98 and 100 ng/10(6) cells in CEM cells treated for 1 hour with ferric ammonium citrate or FeTF, respectively. FeTF did not increase cytoplasmic-free calcium in CEM cells loaded with fura-2, indicating that binding of FeTF to transferrin receptors did not open membrane Ca2+ channels or release intracellular Ca2+. In addition, pretreatment of cells with desferrioxamine, but not ferrioxamine, blocked the FeTF-induced increase in PKC-beta transcripts. Therefore, iron as FeTF (not soluble iron or nonferric TF) stimulates transcription of the CEM cell PKC-beta gene. Transcriptional rate of the PKC-beta gene does not correlate with cellular iron content as judged by ferritin measurements. Furthermore, the requirement for FeTF does not appear to reflect activation of a classic agonist pathway as judged by stable cellular Ca2+. These data suggest that delivery of iron by FeTF to one or more specific cellular compartments may stimulate PKC-beta gene transcription in CEM cells.

Calcium↗
PubMed1991

Phase I clinical and pharmacokinetic trial of flavone acetic acid.

Flavone acetic acid is a synthetic benzopyrone derivative with an unknown mechanism of action. Thirty-eight patients (30 men and 8 women) were treated once a week for 4 weeks every 5 weeks with doses of flavone acetic acid ranging from 0.33 to 12.5 g/m2. At doses less than or equal to 3.9 g/m2, the drug was administered intravenously over 1 hour; at doses greater than or equal to 5.28 g/m2, the infusion period was lengthened to 6 hours. Treatment of all patients included hydration before and after treatment and alkalization to maintain urine pH at greater than or equal to 6.5. A dose-limiting toxic effect was hypotension at 10 g/m2. Pharmacokinetic studies revealed linear behavior in the eight patients studied, beginning at 3.9 g/m2. Peak plasma levels ranged from 125 to 630 micrograms/mL, with a mean terminal half-life of 22.4 hours. Immunologic monitoring was performed in three patients at 10 g/m2. A transient increase in CD16- and/or Leu-19-positive cells was noted in all three patients. In one patient, this increase correlated with a 10-fold increase in K562 cell killing. There were no objective tumor responses seen in this trial. The recommended phase II dose on this schedule is 8 g/m2. Further studies to elucidate the drug's mechanism of action and to define its immunologic properties are recommended.

Adult↗
PubMed1991

A phase II study of high-dose continuous infusion interleukin-2 with lymphokine-activated killer cells in patients with metastatic melanoma.

Thirty-three patients with metastatic melanoma were treated in a phase II study with an intravenous continuous infusion (IVCI) of interleukin-2 (IL2) given with lymphokine-activated killer (LAK) cells. The dose of IL2 was the optimal priming dose for LAK-cell induction, followed by the maximally tolerated LAK-cell dose that could be given by an IVCI schedule as determined by a previous phase I trial. The CI schedule was chosen for evaluation because of a postulated reduction in toxicity with the possibility of administering a more prolonged IL2 infusion and because greater rebound lymphocytosis and LAK-cell generation had been reported using this dose and schedule. The 33 patients were similar in age, performance status, and sites of disease to those treated in previous IL2 trials. All patients were assessable for response and toxicity. One patient (3%) achieved a partial response of 10 months duration. There were no other clinically significant responses. Significant toxicity included hypotension requiring pressors (45%), dyspnea (36%), renal insufficiency (24%), hepatic dysfunction (66%), and cardiac arrhythmias (18%). These toxicities reversed with cessation of the infusion. There were four deaths during the first 30 days of treatment, three from infection (one related to central line, one related to LAK cells, one related to tumor), and one from tumor-related hemorrhage. Toxicity was unexpectedly high and at least comparable to that seen in previous studies using a high-dose IV bolus schedule of IL2. When comparing the IVCI schedule with high-dose bolus IL2 to LAK cells in nonrandomized but sequential studies in patients with advanced melanoma, it appears that CI IL2 is less efficacious.

Adult↗
PubMed1990

Phase I study of high-dose continuous-infusion recombinant interleukin-2 and autologous lymphokine-activated killer cells in patients with metastatic or unresectable malignant melanoma and renal cell carcinoma.

The current study was undertaken to determine the maximum tolerated dose of recombinant interleukin-2 (rIL-2) that could be administered as a continuous infusion in conjunction with autologous lymphokine-activated killer (LAK) cells. All 55 patients in this study received a priming dose of rIL-2 of 1.0 mg/m2 per day given as a continuous infusion over 4.5 days. Patients later received (days 11-16) one of three doses of rIL-2 per day (1.0, 1.25, or 1.50 mg/m2) in conjunction with LAK cells given on days 11, 12, and 14. Because of unacceptable toxicity occurring early in the LAK cell phase of therapy at the rIL-2 dose level of 1.50 mg/m2, we concluded that the maximum tolerated dose of rIL-2 given as a continuous infusion with LAK cells is 1.25 mg/m2 per day.

Adult↗
PubMed1990

Metastatic malignant melanoma treated with combined bolus and continuous infusion interleukin-2 and lymphokine-activated killer cells.

Fifty patients with advanced melanoma received high-dose bolus and continuous infusion interleukin-2 (IL-2) with lymphokine-activated killer (LAK) cells in an attempt to improve the therapeutic index of this active but toxic therapy. Treatment began with up to nine bolus doses of IL-2 administered over 3 days. After 1 day of rest, patients underwent daily leukapheresis for 4 days, and the leukocytes were cultured with IL-2 in vitro to prepare LAK cells. Continuous infusion IL-2 was begun 1 day after the last leukapheresis and continued for up to 148 hours; LAK cells were administered on days 1, 2, and 4 of the infusion. Responding patients were eligible to receive up to two additional cycles of therapy at 3-month intervals. Most patients completed each cycle without dose reduction. One patient had a complete response and six patients had partial responses (14% response rate). The complete responder and three of the partial responders (8%) remain free from disease progression with follow-up of 21 to 24 months. Of these four patients with durable remissions, one had extensive liver and lymph node metastases, one had lymph node, pleural, and parenchymal lung metastases, and two had disease limited to lymph nodes or subcutaneous tissues. Seventeen patients (34%) required pressors for hypotension, three patients (6%) developed hemodynamically significant arrhythmias, and six patients (12%) developed dyspnea at rest, but none required intubation and there were no treatment-related deaths. Unacceptable toxicity developed in two patients during bolus IL-2 administration and therapy was aborted; both returned to baseline status within 4 days of discontinuing IL-2. Fever, oliguria, and elevated creatinine or transaminase levels occurred frequently but were also transient. Despite less frequent severe toxicity with this modified regimen, these results confirm the ability of IL-2 and LAK cell therapy to induce durable remissions in some patients with advanced melanoma.

Adult↗
PubMed1989

Transcriptional regulation of transferrin receptor expression by cultured lymphoblastoid T cells treated with phorbol diesters.

Expression of transferrin receptors (TFR) is required for lymphocyte proliferation. Treatment of lymphoblastic leukemia cell lines with phorbol diester tumor promoters decreases proliferation and induces differentiation. Among changes induced by phorbol diesters is decreased cell surface expression of TFR. To elucidate effects of phorbols on lymphocyte growth and differentiation, we examined TFR expression by measuring 125I-transferrin binding, levels of TFR mRNA by Northern analysis and dot-blot hybridization, and rates of TFR gene transcription by nuclear run-on experiments in CCRF-CEM lymphoblastoid T cells treated with PMA or phorbol dibutyrate. Cell surface expression of TFR was decreased 60 to 85% within 2 min of exposing cells to phorbols and remained decreased for 96 h. Steady state levels of TFR mRNA decreased to less than 30% of control after 48 h. After treating cells with actinomycin D, estimated TFR mRNA t 1/2 was 2.7 h and was unaltered in phorbol-treated cells. Levels of TFR mRNA were not affected by treatment of cells with cycloheximide in either control or phorbol-treated cells. Therefore, post transcriptional mRNA processing by protein factors did not account for decreased TFR mRNA in phorbol-treated cells. Compared to baseline levels, rates of TFR gene transcription in PMA-treated cells increased up to two-fold during the initial 6 h of culture, then decreased over the ensuing 12 h to less than 10% of baseline values. This pattern was not seen in control cultures. Therefore, regulation of TFR gene transcription is a consequence of treating CEM cells with phorbol diesters. Cell surface expression of TFR in phorbol-treated lymphoblastoid T cells may be mediated in part at the level of gene transcription.

Antigens, Surface↗
PubMed1989

A phase II study of interleukin-2 and lymphokine-activated killer cells in patients with metastatic malignant melanoma.

Thirty-six patients with metastatic melanoma were entered into a study of the therapeutic efficacy of adoptive immunotherapy with high-dose interleukin-2 (IL-2) and lymphokine-activated killer (LAK) cells. Thirty-two patients who received all components of the therapy are evaluable for response, and all patients are evaluable for toxicity. Sites of disease included lung, liver, subcutaneous nodules, and intra-abdominal metastases. One complete response (CR) and five partial responses (PRs) resulted from treatment (19% response rate). The median response duration was 5 months, with the durable CR continuing at 31+ months and one durable PR continuing for 13 months. Sites of response included lung, liver, subcutaneous nodules, and lymph nodes. Response, response duration, or site of response did not correlate with the total dose of IL-2 administered, rebound lymphocytosis, or the number of LAK cells infused. Toxicity included hypotension, fluid retention with a "capillary leak syndrome" in most patients, and transient multiorgan dysfunction that resolved promptly after the completion of therapy. Adverse cardiac events occurred in 16% of patients, with one myocardial infarction leading to a death. This study confirms the activity of the initial IL-2/LAK cell regimen in metastatic melanoma reported by Rosenberg et al, supporting the concept of adoptive immunotherapy as an important new treatment approach for this disease.

Adult↗
PubMed1988

Phase I clinical trial of carbetimer.

Carbetimer (carbethimer, N-137, NED-137, carboxyimamidate) is a low molecular weight polyelectrolyte with antitumor activity in a variety of tumor models. This phase I trial evaluated a single dose of carbetimer infused over 1-2 h every 28 days. Forty-three patients received 71 courses of the drug at doses ranging from 180 to 8500 mg/m2. The dose-limiting toxicity was hypercalcemia (serum calcium greater than 12.5 mg/dl) noted in two of three patients at a dose of 8500 mg/m2. Serum calcium levels between 10.5 and 12.5 mg/dl were noted in an additional three patients treated at doses greater than or equal to 1600 mg/m2. Calcium balance studies in three patients treated at 6500 mg/m2 revealed an increase in urinary cyclic AMP and phosphate excretion after treatment accompanied by a mild elevation of serum parathyroid hormone. Immunological studies in these patients revealed a statistically significant increase in the percentage of peripheral T-helper cells. An increase in the T-helper/suppressor cell ratio was observed in two of the three patients studied. Interleukin 2 production by phytohemagglutinin-stimulated peripheral mononuclear cells was increased in two of three patients. One patient with a renal cell carcinoma showed a mixed response. The recommended dose for phase II trials as assessed from this study is 6500 mg/m2 as a single dose every 28 days.

Adult↗
PubMed1988

Laboratory correlates of adoptive immunotherapy with recombinant interleukin-2 and lymphokine-activated killer cells in humans.

Adoptive immunotherapy with interleukin 2 (IL-2) and lymphokine-activated killer (LAK) cells (IL-2/LAK) is a technically demanding cancer therapy dependent upon large scale isolation and culture of lymphocytes. An important question is whether this technology can be accomplished routinely outside of highly specialized centers. In addition, no systematic examination of laboratory correlates of IL-2/LAK therapy in humans has been reported to date. The objectives of this report are to address two issues relevant to IL-2/LAK therapy. (a) Can IL-2/LAK therapy be accomplished outside of previously identified centers of expertise? (b) What are the relevant laboratory/clinical parameter correlations? The six institutions in the National Cancer Institute extramural trial treated 83 evaluable patients with renal cancer, malignant melanoma, or colon cancer with IL-2/LAK by a uniform protocol. Patients received 5 days of IL-2 priming, then daily leukaphereses for 5 days starting 48 h after IL-2 to harvest cells. Mononuclear cells were isolated, then cultured in roller bottles in 1-liter aliquots for 3 to 4 days at a cell density of 1.5 x 10(6) per ml with recombinant IL-2, 1500 units per ml. Cells were harvested and administered to patients with additional IL-2. Administration of IL-2 regularly induced lymphopenia and rebound lymphocytosis. Leukapheresis yields and numbers of LAK cells generated in culture and reinfused into patients correlated directly with peak lymphocyte counts achieved by IL-2 administration. Mean mononuclear cell recovery per 5 days of leukapheresis (+/- SEM) was 14.3 +/- 0.8 x 10(10). Average volume of cells cultured per patient was 95 liters (range, 41 to 235). Mean yield of cells harvested from cultures was 53%. Mean total number of LAK cells infused per patient was 7.6 +/- 0.4 x 10(10) (range, 2 to 15.2 x 10(10]. LAK activity was measured in vitro by lysis of 51Cr-labeled natural killer-resistant Daudi and fresh tumor targets. LAK effector cells regularly lysed these targets in vitro. Neither tumor reduction nor clinical toxicity correlated with dose or with cytolytic activity of LAK cells, or with other laboratory parameters including base-line lymphocyte count and IL-2-induced lymphocytosis. We conclude: (a) large quantities of LAK effector cells with tumoricidal activity can be generated routinely at different centers; (b) neither in vitro LAK activity nor numbers of LAK cells infused were predictive of clinical efficacy or toxicity. There is a need to identify other laboratory or clinical parameters more predictive of IL-2/LAK therapeutic efficacy or toxicity.

Colonic Neoplasms↗
PubMed1988

Guidelines for clinical protocols for chronic lymphocytic leukemia: recommendations of the National Cancer Institute-sponsored working group.

The National Cancer Institute (NCI)-sponsored Chronic Lymphocytic Leukemia (CLL) Working Group was convened to develop a set of standardized eligibility, response, and toxicity criteria for clinical trials. We recognized the previous efforts in 1967 (published again in 1973 as the report of the Chronic Leukemia-Myeloma Task Force [1] and 1978 of Cancer and Leukemia Group B (CALGB) [2]). We have used these reports for guidance during the current effort. Several noteworthy developments in the past few years have made it necessary to modify the previous guidelines. First, the diagnostic criteria for CLL and its clinical staging have been developed and well defined. Second, although staging systems facilitated entry of comparable and relatively homogeneous groups of patients in clinical trials, the definitions of response (CR) and partial response (PR) were not uniformly adopted from the previous guidelines in the clinical trials (Tables IA, IB); therefore, comparisons of results obtained in different studies became difficult. Third, there has been an improvement in our understanding of the immunology and biology of CLL. Finally, we are witnessing the emergence of several chemotherapy agents that promise impressive activity in CLL (e.g., 2'-deoxycoformycin [3], fludarabine monophosphate [4, 5]), and thereby offer the potential for improving survival time in this disease. To best identify regimens worthy of continued pursuit in large comparative trials, standardized guidelines for evaluation are essential. A number of laboratory investigations are also presented for which scientific interest is high yet relevance remains to be determined; thus, they are presented as companion studies to the clinical trials. This mechanism allows for flexibility in the testing of these questions and for additional ideas in the future without requiring modification of an entire treatment protocol. The following guidelines were developed to be used as a form of standardization for clinical trials, incorporating current technologies, yet remaining relevant to the general hematology/oncology community. Based on the membership of the Working Group, it is expected that these guidelines will serve as the criteria for most clinical trials in the near future.

Antineoplastic Agents↗
PubMed1987

Disparity between expression of transferrin receptor ligand binding and non-ligand binding domains on human lymphocytes.

We compared transferrin receptor (TfR) expression on human peripheral blood lymphocytes (PBL) activated by phorbol myristate acetate (PMA) or L-phytohemagglutinin (LPHA) using two techniques: (1) 125I-iron-saturated transferrin (FeTf) binding, (2) reactivity with monoclonal anti-TfR antibodies--OKT9 and B3/25. These monoclonal antibodies do not block FeTf binding, and therefore bind to TfR domains separate from the ligand binding site. Unstimulated PBL bound fewer than 1,000 molecules of 125I-FeTf per cell, and less than 5% of cells expressed TfR antigens detected by OKT9 or B3/25. 125I-FeTf binding and antibody binding increased in parallel on LPHA-activated PBL. After exposure to LPHA for 72 hr, 125I-FeTf binding increased 100-fold to 10(5) molecules per cell and greater than 50% of cells expressed TfR antigens. By contrast, PMA activation of PBL markedly increased binding of OKT9 and B3/25 but not the binding of 125I-FeTf. Cell surface expression of TfR antigens seen by OKT9 and B3/25 did not differ between LPHA- and PMA-activated PBL. However, after 72 hr with PMA, 125I-FeTf binding increased only 6-fold and consistently remained at less than 10(4) molecules per cell. Therefore, PMA induced a disparity between expression of TfR ligand binding domains and immunological domains at the cell surface. Cell proliferation assessed by fluorescent DNA analysis was similar in cultures stimulated by LPHA or PMA. These data indicate that lymphoid cells may possess a mechanism for modulating TfR expression in which down-regulation of FeTf binding occurs without receptor internalization. Alternatively, it is possible that this observation may reflect a membrane perturbation effect of PMA.

Antibodies, Monoclonal↗
PubMed1987

Iron-transferrin-induced increase in protein kinase C activity in CCRF-CEM cells.

Iron transferrin has been found to induce a mean 10-fold increase in the activity of protein kinase C in CCRF-CEM cells. This increase was not detectable up to 45 min after treatment of cells with iron transferrin, although after 60 min, a maximal increase in enzyme activity was observed. Similarly, iron transferrin at concentrations of 0.1-0.5 microgram/ml did not alter protein kinase C activity, while concentrations of iron transferrin of 1-100 micrograms/ml induced a maximal increase in enzyme activity. Apotransferrin and iron in the form of ferric citrate, as well as complexes of transferrin with copper, nickel, zinc, manganese, and cobalt did not increase protein kinase C activity. Additionally, CCRF-CEM cells pretreated with either actinomycin D or cycloheximide and then incubated with iron transferrin did not exhibit increased enzyme activity. Treatment with iron transferrin was found to have no effect on protein kinase C activity in normal human peripheral blood lymphocytes and in HL60, Daudi, and U937 cells. However, normal lymphocytes stimulated with phytohemagglutinin for 48 hr exhibited a 2-fold increase in protein kinase C activity following treatment with iron transferrin. These results indicate a specific effect of iron transferrin on protein kinase C activity in CCRF-CEM cells and in mitogen-stimulated human lymphocytes that may occur through increased synthesis of the enzyme.

Cell Line↗