Growth suppression of human leukemic cells in vitro by L-ascorbic acid.

The suppressive effect of L-ascorbic acid on the growth of bone marrow cells from patients with acute nonlymphocytic leukemia was studied using a modified agar culture method featuring daily feeding to allow the growth of leukemic cell colonies. In seven of 28 patients (25%), the numbers of leukemic cell colonies grown in culture were reduced to 21% of control by the addition of L-ascorbic acid (0.3 mM) to the culture medium. Glutathione did not suppress leukemic cell colonies although it has a similar oxidation-reduction potential to that of L-ascorbic acid. The addition of L-ascorbic acid reduced the pH of the medium. However, a comparable reduction of pH by the addition of HCl did not suppress leukemic cell colonies. In simultaneous cultures for leukemic and normal marrow cells, the suppression of leukemic cell colony was noted with a concentration of L-ascorbic acid as low as 0.1 mM (a concentration achievable in vivo), but normal myeloid colonies were not suppressed until the concentration of L-ascorbic acid reached an extremely high level (1 mM). In conclusion, growth of leukemic cells in culture was suppressed by L-ascorbic acid in a substantial proportion of patients with acute nonlymphocytic leukemia. This suppression was a specific effect of L-ascorbic acid and was not due to its oxidation-reduction potential or pH change. Leukemic cells were selectively affected at an L-ascorbic acid concentration attainable in vivo while normal hemopoietic cells were not suppressed.

Improved growth of in vitro colonies in human acute leukemia with the feeding culture method.

Bone marrow cells freshly aspirated from the 10 consecutive untreated adult patients with acute nonlymphocytic leukemia were cultured by 2 different methods: the conventional agar culture method for myeloid colony formation and its modification by daily feeding with culture medium. In 5 patients, colonies grew in much higher numbers (4.7-to 330-fold) with feeding than without. Three patients grew colonies only with feeding. Two of these 3 patients required L-ascorbic acid in the fed medium for colony growth. Colonies did not grow from the remaining 2 patients by any method. In 7 patients the number of colonies grown with feeding were much higher, up to 170 times higher, than were those from normal control marrows, which grew the same number of colonies regardless of feeding or L-ascorbic acid. Peroxidase and Wright's stains indicated the myeloid differentiation of the cells in the leukemic marrow colonies. The leukemic origin of the colonies was proven by chromosomal analysis. The wide range of linearity between the number of cells plated and the number of colonies grown permits quantitative assay of colony-forming leukemic cells. This assay should be valuable for studies of chemotherapy, growth regulation, and differentiation of leukemic cells.

Clinical correlations of leukemic clonogenic cell chemosensitivity assessed by in vitro continuous exposure to drugs.

This study was performed to assess the value of prolonged, as opposed to short-pulse, in vitro exposure of leukemic cells to chemotherapeutic drugs in leukemic clonogenic assay for prediction of clinical response. In 21 patients with acute nonlymphocytic leukemia treated with intensive combination chemotherapy based on an anthracycline and 1-beta-D-arabinofuranosylcytosine infusion, chemotherapy sensitivity of leukemic clonogenic cells was assessed in comparison with that of normal myeloid clonogenic cells by the in vitro continuous exposure to drugs throughout the entire culture period. Analysis of these in vitro data in terms of prediction of achieving clinical complete remission was carried out in comparison with data on 22 cases in which in vitro sensitivity was assessed by the pulse 1-hr exposure. The in vitro sensitivity index, expressed as a log odds ratio, was positive (greater than 0) in 8 of 11 patients achieving complete remission and negative (less than 0) in 7 of 10 patients failing to achieve complete remission, with an overall correlation of 71%. This is at least as good as the pulse exposure method, which has a correlation of 68%. If sensitivity indexes of marginal magnitudes (--1.0 approximately +1.0) are excluded, the correlation increases to 92% (12 of 13 patients). The correlation appears to improve especially for 1-beta-D-arabinofuranosylcytosine by the continuous exposure method (71%) as compared with the pulse method (57%). This study establishes the feasibility of an in vitro chemotherapy sensitivity testing of leukemic clonogenic cells by continuous in vitro drug exposure and suggests that the continuous exposure method may be better than the pulse method for antimetabolites such as 1-beta-D-arabinofuranosylcytosine. The data also suggest that simulation of the in vivo drug schedule may be important in this in vitro test.

Alternating combination chemotherapy and levamisole improves survival in multiple myeloma: a Southwest Oncology Group Study.

Previously untreated patients with multiple myeloma were entered on a randomized clinical trial to determine whether the use of alternating combination chemotherapy, including vincristine, doxorubicin, alkylating agents, and prednisone (160 patients) was more effective than conventional chemotherapy with melphalan and prednisone (77 patients), and whether the addition of the immunomodulating agent levamisole to maintenance chemotherapy enhanced the survival of patients achieving remission. The treatment groups were well matched for all major factors. The more aggressive chemotherapy was more effective at inducing remission, with a significantly higher proportion of patients achieving at least 75% tumor mass regression (53% with alternating combinations versus 32% with melphalan-prednisone, p = 0.002). Furthermore, the median survival was increased to 43 months with alternating combination chemotherapy as compared to 23 months with melphalan-prednisone (p = 0.004). After six to 12 months of induction therapy, 84 patients achieving remission were rerandomized to receive maintenance chemotherapy alone or with the addition of levamisole. The survival from the start of maintenance therapy was longer in patients receiving the added levamisole than with chemotherapy alone (p = 0.01). These findings support the use of aggressive multiagent chemotherapy for remission induction in patients with advanced-stage multiple myeloma.

High rate of long-term survival in adult acute leukemia following ten-day chemotherapy (OAP) induction. Maintenance with chemotherapy or chemotherapy plus BCG vaccine.

In this Southwest Oncology Group (SWOG) study, 216 adults with acute leukemia were treated with ten-day chemotherapy consisting of vincristine sulfate (Oncovin), cytarabine (ara-C) (100 mg per square meter of body area per day by 24-hour infusion), and prednisone (ten-day OAP). The results were compared with those of a previous SWOG study in which cytarabine (200 mg per square meter of body area per day) was given for five days (five-day OAP). Patients entering complete remission (CR) were given three consolidation courses of five-day OAP and randomized to maintenance chemotherapy alone (32 patients) or combined with BCG vaccine (24 patients). For 160 previously untreated patients with acute myelogenous leukemia, there was no difference in remission rates (53% vs 43%) or median survival times (48 vs 47 weeks) between ten-day and five-day OAP. The difference in duration of CR (74 vs 54 weeks, respectively) between the two maintenance arms was not statistically significant. However, 14% of evaluable patients with acute myelogenous leukemia and 26% of those achieving CR were alive and in remission more than five years.

Analysis of the growth enhancing effect of L-ascorbic acid on human leukemic cells in culture.

The effect of L-ascorbic acid (LAA) on the in vitro colony growth of leukemic cells from the marrows of patients with acute nonlymphocytic leukemia was studied using a modified agar culture method featuring daily feeding. In 10 of 31 patients (32%) the growth was enhanced with supplementation of LAA in culture. The average number of colonies was reduced to 26% if LAA was deleted from culture. This growth enhancing effect appears to be specific to LAA: neither glutathione which has redox potential similar to LAA nor the acidification of culture medium with HCI to the pH of medium containing LAA is effective. This effect is also selective for leukemic marrows, and normal marrow colonies are not affected over wide range of LAA concentrations (0 to 300 microM) which are achievable in human in vivo.

Respiratory dysfunction in thrombotic thrombocytopenic purpura.

Thrombotic thrombocytopenic purpura is a rare disease characterized by microangiopathic hemolytic anemia, thrombocytopenia, neurologic abnormalities, fever and renal dysfunction. in six of seven consecutive patients with thrombotic thrombocytopenic purpura seen in an eight month period, respiratory impairment was present. Respiratory dysfunction was characterized by tachypnea, hypoxemia nad infiltrates on chest roentgenogram. Five patients required mechanical ventilation. Two patients had cardiogenic pulmonary edema, but they remained hypoxemic despite treatment for pulmonary edema and maintenance of normal pulmonary capillary wedge pressure for more than 36 hours. Four patients died and autopsies revealed pulmonary edema, hemorrhage and hyaline thrombi. Pathologic examination of the heart also showed hyaline thrombi. Information from out patients with thrombotic thrombocytopenic purpura implicates respiratory dysfunction as a component of this disease as well as the classically described pentad. Cardiogenic and noncardiogenic pulmonary edema and possibly bleeding into the lung contributed to pulmonary impairment.

Suppressor T cells in tolerance to deaggregated horse anti-human thymocyte globulin in man.

To understand the mechanism by which deaggregated horse anti-human thymocyte globulin (dATG) fails to induce untoward immunological reactions in man, three patients who received ATG and two patients who received dATG were studied for evidence of sensitization or tolerance to the foreign globulin. The ATG but not the dATG recipients developed allergic or serum sickness reactions; antihorse serum antibody could be detected in their serum and their blood cells proliferated in vitro in the presence of horse serum and secreted antihorse serum antibodies (P less than 0.001). Tolerance of the dATG recipients was shown to be mediated by specific T suppressor cells that carry receptors for horse serum and could be detected in the blood of one patient, whom we have studied serially, 13 weeks after therapy. Deaggregated ATG does not induce allergic or serum sickness reactions. It induces tolerance to the foreign protein via the generation of specific short-lived suppressor cells.

Growth promotion of human leukemic colonies in vitro with human malignant effusions.

Twenty-four malignant ascites, pleural, or pericardial effusions were obtained from 23 patients with a variety of malignant neoplasms. Sera derived from these malignant effusions (ME) were tested against fetal calf serum (FCS) for its activity to promote in vitro growth of human acute nonlymphocytic leukemia (ANLL) cells, termed operationally colony promoting activity (CPA). Five ME had CPA levels as high as or higher than FCS, 11 ME had somewhat lower CPA than FCS (p less than 0.05), 8 ME had considerably lower CPA than FCS (p less than 0.01), and one ME had no CPA. Low CPA was not due to inhibitory activity against colony growth. There is suggestion that high level of CPA in ME is associated with poor prognosis of the patient from whom the ME is obtained. Studies of CPA in ME might help elucidate growth regulation of malignant cells. Moreover, ME with high CPA is of practical value for the growth of leukemic colonies, thus enabling in vitro studies such as the chemotherapy sensitivity test.

Total parenteral nutrition with glutamine in bone marrow transplantation and other clinical applications (a randomized, double-blind study)

In a paper by Ziegler et al (Ann Intern Med 116: 821-828, 1992), total parenteral nutrition supplemented with L-glutamine (TPN/GLN) was reported beneficial in patients receiving bone marrow transplantation (BMT) for hematologic malignancies. By using a similar protocol, we studied 29 patients with both hematologic malignancies and solid tumors, and with both allogeneic and autologous BMTs. In a double-blind, randomized approach, patients were given isocaloric, isonitrogenous TPN after BMT until they consumed 50% of their required diet orally. Total body water and extracellular water were measured before and after TPN in 10 patients. Total body water increased in patients receiving standard TPN and decreased significantly in patients receiving TPN/GLN. Length of hospital stay after BMT was significantly (5.8 days) less in patients receiving TPN/GLN. Incidence of positive bacterial cultures, clinical infections, and mortality did not differ significantly between the two groups. When the groups were subdivided into patients with hematologic malignancies and those with solid tumors, there were no significant differences in the above variables associated with TPN/GLN. In 17 of 30 additional hospitalized patients receiving standard TPN, substitution of TPN/GLN did not have discernible clinical or laboratory effects but appeared to be safe. Inclusion of patients with solid tumors and a higher mortality in our patients may have obscured beneficial effects of TPN/GLN observed by others.

Adriamycin combined with 10-day Ara-C, vincristine, and prednisone (10-day ADOAP) in the treatment of adult acute leukemia patients under fifty years of age. A Southwest Oncology Group Study.

In a twelve-month period, 56 consecutive patients with acute leukemia, aged 15-50, were treated by administration of a 10-day continuous infusion of Ara-C in combination with adriamycin, oncovin and prednisone (10 day ADOAP). Of 50 evaluable patients, there were 39 complete remissions (78%) with a median remission duration of 71 weeks. After adjustment for age and other known prognostic factors, the complete remission rate is still 10% higher than that found using a similar regimen without adriamycin.

Rubidazone in combination with Ara-C, vincristine and prednisone (ROAP) in the treatment of adult acute leukemia. A Southwest Oncology Group Study.

In an 18-month period, 340 consecutive adult patients with acute leukemia were treated using a 7-day continuous infusion of Ara-C in combination with rubidazone, vincristine and prednisone (ROAP). Of 334 (96%) evaluable cases, 77% were 50 years of age or older. The complete remission (CR) rate was 51% with a standard error of 3%. After adjustment for known prognostic factors this overall CR rate is 10% higher than the predicted CR rate when compared to the last completed SWOG study which used adriamycin in combination with a similar regimen of Ara-C, vincristine, and prednisone. The CR rate in patients over 50 years of age was particularly noteworthy. Using rubidazone, the CR rate was 46.1% (116/256) compared to 37.4% (91/243) for the adriamycin study in this poorly responding age group. The median survival time achieved was 27 weeks. However, in the age groups 40-49 years and 50-59 years the median survival was 70 and 44 weeks, respectively.

Pure red cell aplasia: three cases responding to immunosuppression.

Successful treatment of three patients with red cell aplasia is presented. No thymoma or other underlying etiology was discovered. An autoimmune disease with intramedullary destruction of red cell precursors was suspected. All patients responded to prednisone and/or immunosuppressive therapy and have maintained normal hemoglobin levels for 3, 7, and 2.5 years without recurrence. The pathogenesis and therapy of red cell aplasia is discussed.

Splenectomy and antiplatelet agents in thrombotic thrombocytopenic purpura.

Ten patients with thrombotic thrombocytopenic purpura (TTP) were studied retrospectively. The male:female ratio was 2:3 and the median age was 27 years. Six patients were alive one-half to 18 years after the onset of the disease. Four of these patients underwent emergency splenectomy and received antiplatelet drugs. Of the remaining two, one responded to splenectomy and the other had received a short course of aspirin therapy. The study supports the usefulness of splenectomy and/or antiplatelet agents in the treatment of TTP.

Severe tissue trauma triggers the autoimmune state systemic lupus erythematosus in the MRL/++ lupus-prone mouse.

Tissue damage associated with a severe injury can result in profound inflammatory responses that may trigger autoimmune development in lupus-prone individuals. In this study, we investigated the role of a large full-thickness cutaneous burn injury on the early onset of autoimmune disease in lupus-prone MRL/++ mice. MRL/++ mice (chronic model) exhibit autoimmune symptoms at >70 weeks of age, whereas MRL/-Fas(lpr) mice (acute model) develop autoimmune disease in 17-22 weeks due to a lymphoproliferative mutation. Autoimmune disease developed in MRL/++ mice (4-15 weeks post injury) is manifested by skin lesions, vasculitis, epidermal ulcers, cellular infiltration, splenomegaly, lymphadenopathy, hypergammaglobulinemia, elevated autoantibodies and renal pathologies including proteinuria, glomerulonephritis and immune complex deposition; complications that contribute to reduced survival. Transcription studies of wound margin tissue show a correlation between the pathogenic effects of dysregulated IL-1beta, IL-6, TNF-alpha and PGE(2) synthesis during early wound healing and early onset of autoimmune disease. Interestingly, MRL/++ mice with healed wounds (30-40 days post burn) strongly rejected skin isografts. Conversely, skin isografts transplanted onto naive age-matched MRL/++ littermates achieved long-term survival. Collectively, these findings suggest that traumatic injury exacerbates inflammatory skin disease and severe multi-organ pathogenesis in lupus-prone mice.

Expression of IgGFc receptors on human plasma cells.

Plasma cells that were obtained in bone marrow aspirates from patients with plasma cell dyscrasias were assessed for the expression of IgGFc receptors. A sensitive EA rosette assay and direct immunofluorescence were combined to quantitate plasma cells that expressed IgGFc receptors. Two patients with nonsecretory disorders had large numbers of receptor positive cells (98 and 78%). The remaining patients, all of which had been treated with cytotoxic drugs prior to testing, had significant numbers of IgGFc receptor positive cells (36-86%) and the number of FC receptor positive cells was increased by storing the cells at 4 degrees C for 18 hours prior to performing the rosette assay.

Immune competence in a patient with Hodgkin's disease and relapsing toxoplasmosis.

A 40 year old woman with Hodgkin's disease twice developed signs of encephalitis while being treated with prednisone and cyclophosphamide for 10 months. Since on both occasions her Toxoplasma dye test titer was 1 : 8000 or higher, she was treated on suspicion of toxoplasmosis with sulfadizine and pyrimethamine. Her tumor therapy was changed to bleomycin with lower doses of prednisone for 12 months. After death from central pontine myelinolysis, Toxoplasma and cytomegalovirus could be isolated, but no lesions attributable to these infectious agents were present. Maintenance of the patient's immune competence suggested an inquiry into the effects of the chemotherapeutic agents and of tumor infiltration for their respective interference with immunity. Using hamsters with chronic latent toxoplasmosis, it was found that both cortisone and cyclophosphamide caused recrudescence of chronic inapparent infection, that vinblastine and bleomycin interfered only slightly with the development of immunity, whereas in infiltrating lymphoma permitted immunity to develop normally. It is concluded that greater attention should be directed to the immunosuppressive effects of tumor treatment. By choice of an effective tumor therapy which is least immunosuppressive, and if necessary under cover of antimicrobial therapy, a patient with Hodgkin's disease can be aided in developing immunities which he may subsequently be able to maintain.