Bortezomib decreases the magnitude of a primary humoral immune response to transfused red blood cells in a murine model

BACKGROUND

Few therapeutic options currently exist to prevent or to mitigate transfusion-associated red blood cell (RBC) alloimmunization. We hypothesized that bortezomib, a proteasome inhibitor currently being utilized for HLA alloantibody and ADAMTS13 autoantibody reduction, may be beneficial in a transfusion setting. Herein, we utilized a reductionist murine model to test our hypothesis that bortezomib would decrease RBC alloimmune responses.

STUDY DESIGN AND METHODS

Wild-type mice were treated with bortezomib or saline and transfused with murine RBCs expressing the human KEL glycoprotein. Levels of anti-KEL immunoglobulins in transfusion recipients were measured by flow cytometry. The impact of bortezomib treatment on recipient plasma cells (PCs) and other immune cells was also assessed by flow cytometry and immunofluorescence.

RESULTS

After bortezomib treatment, mice had a 50% reduction in splenic white blood cells and a targeted reduction in marrow PCs. Mice treated with bortezomib before the transfusion of KEL RBCs became alloimmunized in three of three experiments, although their serum anti-KEL IgG levels were 2.6-fold lower than those in untreated mice. Once a primary antibody response was established, bortezomib treatment did not prevent an anamnestic response from occurring.

CONCLUSION

To the extent that these findings are generalizable to other RBC antigens and to humans, bortezomib monotherapy is unlikely to be of significant clinical benefit in a transfusion setting where complete prevention of alloimmunization is desirable. Given the impact on PCs, however, it remains plausible that bortezomib therapy may be beneficial for RBC alloimmunization prevention or mitigation if used in combination with other immunomodulatory therapies.

Antineoplastic activity of idazoxan hydrochloride

PURPOSE

Idazoxan hydrochloride (IDA) is a 241 molecular weight imidazoline and adrenoreceptor ligand. It binds to mitochondrial membranes and promotes apoptosis of pancreatic beta cells. Since IDA has not been tested against tumor cells, the purpose of our study was to determine if IDA has antineoplastic activity.

METHODS

We used the conversion of a soluble tetrazolium salt to an insoluble formazan precipitate and differential staining cytotoxicity assays to determine if IDA was cytotoxic to cell lines of murine lung cancer and human prostate cancer, as well as to a variety of fresh human tumor samples. We used flow cytometry to analyze cell death and calreticulin expression.

RESULTS

IDA is cytotoxic to both cell lines and against aliquots of specimens of breast, gastric, lung, ovarian and prostate cancers as well as non-Hodgkin's lymphoma. It produces apoptotic cell death and promotes calreticulin expression, suggesting that IDA might be immunomodulatory in vivo.

CONCLUSION

We anticipate that IDA will be clinically useful in cancer treatment.

Enhancement of leukemia rejection by mice successfully treated for L1210 leukemia due to low dose compared to high dose VP-16

We have earlier shown that VP-16 combined with Cyclosporin A (CsA) produces tumor specific immunity to L1210 leukemia in BDF/1 mice [Slater LM, Sweet P, Stupecky M, Reynolds JT. Cyclosporin A/VP-16 produced immunity to L1210 leukemia: the participation of cytotoxic CD(8) T-lymphocytes, Clin Immunol Immunopathol 1995;75:239-45]. Our current studies, designed to determine the role of VP-16 independently of CsA in this effect show that increased dose intensity of VP-16, in the absence of CsA, improves the frequency of 60 day survival of treated mice but impairs the ability of 60 day surviving mice to reject L1210 leukemia challenge. This impairment is associated with progressive diminution of mitogen responses by spleen cells harvested from tumor free VP-16 treated mice.

Etoposide induction of tumor immunity in Lewis lung cancer

PURPOSE

To determine if the antineoplastic effect of etoposide includes alteration in Lewis lung cancer cells which evoke an immunologic response in C57B1/6 host mice.

METHODS AND RESULTS

Of C57B1/6 mice injected with 10(6) Lewis lung cancer (3LL) cells followed by treatment with a single 50 mg/kg dose of etoposide (VP-16), 60% survived over 60 days, in contrast to untreated control mice which died within 30 days. Approximately 40% of surviving mice rejected a subsequent challenge with 3LL. Their splenocytes protected naive mice injected with 3LL. To test if VP-16 treatment produced alterations in 3LL cells, which induce host immunity, leading to tumor rejection, C57B1/6 mice were injected with 3LL cells that had survived an 80-90% lethal concentration of VP-16 in vitro. These cells killed 75% of recipient mice but 60% of the surviving mice rejected challenge with 3LL. Splenocytes harvested from tumor-rejecting mice protected naive mice injected with 3LL.

CONCLUSION

These results support the hypothesis that in addition to its antineoplastic cytotoxic effect, VP-16 induces changes in 3LL cells which are recognized by the host immune system resulting in immune rejection of 3LL. often immunosuppressive and therapeutic advantage is generally based on the tumor cytotoxicity of individual drugs or combinations of drugs [13]. Our earlier work showed a link between the use of cytotoxic chemotherapy with etoposide (VP-16) and the induction of an immune response against syngeneic murine leukemia in the intact host [16]. VP-16 is an immunosuppressive topoisomerase II-inhibiting drug which induces tumor cell apoptosis and is frequently used clinically to treat a variety of tumors [1, 3, 9, 10]. We have noted that the addition of cyclosporin A to VP-16 produces CD8 T lymphocyte-mediated tumor-specific immunity in mice bearing L1210 leukemia [17]. We have extended these experiments to a spontaneously arising non-carcinogen-induced neoplasm, Lewis lung cancer (3LL), and now report that surviving mice successfully treated with VP-16, in the absence of cyclosporin A, reject challenge with 3LL. In addition, results are presented to show that VP-16 modifies 3LL cells rendering them immunogenic. These findings are submitted to support the hypothesis that VP-16-induced cytotoxic changes include cellular membrane alterations in 3LL cells which are recognized by the immune system and cause rejection of this syngeneic lung tumor.

Tumor apoptosis induced by epoxide-containing piperazines, a new class of anti-cancer agents

PURPOSE

The overall purpose of this study was to determine the potential efficacy of epoxide-containing piperazines as a new class of anti-cancer agents. Two representative compounds, specifically NCO-700, a 4-trimethoxyphenyl-substituted epoxide-piperazine, and TOP-008, a 4-phenylpropenyl-substituted epoxide-piperazine were tested in cytotoxic assays with human breast and prostate cancer cell lines. A second objective was to determine if these two compounds had anti-cancer activity in vivo when tested against xenograft tumors in nude mice or human tumors grown under the kidney capsule in mice. A final objective of this study was to establish if NCO-700 and TOP-008 achieved cancer cell killing through an apoptotic mechanism.

METHODS

The anti-proliferative activity of NCO-700 and TOP-008 were tested in a 7 day cell-survival assay utilizing a number of well characterized breast (HS-578T, T47D, MCF-7) and prostate (DU-145, PC-3, LNCaP) cancer cell lines. In vivo studies with the two compounds were performed, in nude mice bearing DU-145 xenograft tumors, and in normal mice in which DU-145 prostate cancer cells and HS-578T breast cancer cells were grown as solid tumors in the subrenal capsules of the animals. Apoptotic cell death of cancer cells was determined by a number of established techniques that detect apoptosis, including the confocal laser microscopy of treated cells and mitochondrial leakage assays utilizing the cationic dye, JC-1. Finally, the activation of the caspase cascade, enzymes that carry out apoptosis in mammalian cells, was examined in treated cells by immunoblot assays.

RESULTS

NCO-700 and TOP-008 displayed cytotoxicity to HS-578T human breast cancer cells, with ED(50) values in the 3-6 microM range. Cytotoxicity to androgen receptor-negative human prostate cancer cells (PC-3 and DU-145 cells) occurred with ED(50) values in the 5-20 microM range. Cytotoxicity to hormone receptor-positive breast and prostate cancer cell lines occurred at 10 to 20-fold higher concentrations of the two compounds. When human prostate (DU-145) or breast cancer (HS-578T) cells were grown as solid tumors in the subrenal capsules of mice, significant anti-tumor activity of NCO-700 was observed at 20 mg/kg and 50 mg/kg body weight respectively, for prostate and breast tumors. In nude mice bearing DU-145 prostate tumor xenografts, 50 mg/kg doses of the two compounds either stopped (TOP-008) tumor growth or slowed (NCO-700) growth. The mechanism of cytotoxicity was shown to be through apoptosis, (a) by confocal microscopy studies revealing nuclear fragmentation, (b) by mitochondrial studies revealing disruption of the mitochondrial membrane and release of the cationic dye, JC-1, into the cytoplasm and (c) by protein immunoblot assays indicating that over a 6 h period, TOP-008 induced a significant accumulation of the pro-apoptotic protein, bak, in the mitochondrial fraction of HS-578T human breast cancer cells, accompanied by activation, at 2.5 h, of caspase-3.

CONCLUSIONS

These studies indicated that the epoxide-containing piperazines, as exemplified by NCO-700 and TOP-008, were effective anti-cancer agents when tested in vitro and in vivo against human breast and prostate tumors. Our studies also indicated that TOP-008 induced the initiation of the caspase cascade leading to apoptosis. Previous toxicology studies in rodents and dogs, as well as a Phase I study in humans, showed NCO-700 to be a well-tolerated, non-toxic compound. Taken together with our current findings, these results suggest that this class of compounds has the potential to be relatively safe, new chemotherapeutic agents for refractory breast and prostate cancers.

Phase I/II trial of low dose cyclosporin A with EP for advanced non-small cell lung cancer

We and others have shown that cyclosporin A (CsA) reverses resistance to etoposide (E) and cis-platinum (P) in vitro and in vivo. To assess the clinical relevance of combined therapy, we studied CsA with EP in patients with advanced non-small cell lung cancer in a phase I/II clinical trial in a University setting. Patients were treated between July 1989 and June 1994 and included 10 females and 34 males with a median age of 61 years and a mean Karnofsky performance status of 80. CsA was given at escalating doses of 1-6 mg/kg per day on days 1-4 of each 21 day cycle with cis-platinum 25 mg/m2 per day and etoposide 100 mg/m2 per days on days 1-3. Response was assessed after each 2 cycles by measuring index lesions. A total of 44 patients received 133 cycles, 22.7% of patients had a partial response and 36.4% had stable disease with 8% 2-year survival. Patients receiving 1-2 mg/kg CsA had a PR rate of 37.5 and 50% SD compared to 19.4 and 33.3% for doses of 3 mg/kg or more. Although no conclusions should be drawn from this small study, the Kaplan-Meier survival curves were statistically significant different for these two groups by the log-rank test (P = 0.047). The 2-year survival of the former group was 25% compared to 4% for the latter. In light of the potential importance of immunomodulation in cancer control, it seems prudent to balance the effects of CsA on P-glycoprotein and other drug resistance pumps against its dose-dependent immunosuppressive activity. Further studies are needed to validate the activity of low dose CsA in combination with standard chemotherapy for lung cancer.

Superiority of cyclosporin A over PSC-833 in enhancement of VP-16 efficacy in murine tumors in vivo

PSC-833, a non immunosuppressive analogue of cyclosporin A, is an effective modulator of the multidrug-resistant tumor phenotype. Since both PSC-833 and cyclosporin A also enhance the cytotoxicity of VP-16 against drug sensitive L1210 leukemia cells in vitro we compared these agents as modulators of VP-16 efficacy in vivo. Compared to VP-16 treatment alone both PSC-833 and cyclosporin A significantly altered the survival of L1210 leukemia-bearing BDF/1 mice and Lewis lung carcinoma-bearing C57/B1 mice. Cyclosporin A enhanced VP-16 efficacy whereas PSC-833 impaired VP-16 efficacy against these murine tumors. Possible reasons for these disparate effects are discussed.

Cyclosporin A enhances paclitaxel toxicity against leukemia and respiratory epithelial cancers

Multidrug resistance is probably the single greatest obstacle to successful systemic therapy of human cancer. We have reported that cyclosporin A (CsA) can overcome multidrug resistance and improve the efficacy of etoposide in a murine model of drug-sensitive leukemia. The combination of CsA and paclitaxel (PCL) was also significantly superior to either drug alone against murine P388 (sensitive) and L1210 (resistant) leukemia. Lung cancer cells provide an ideal model system to study this phenomenon because both de novo and acquired drug resistance occur. Standard chemotherapy for advanced lung cancer is poorly effective, and although PCL is one of the most active new agents for this disease, responses occur in only 20% of patients. In vitro, CsA significantly enhanced the efficacy of PCL against lung (Lu-CSF-1 and 3LL) and oropharyngeal (CSCC-20) cancer cell lines. The combination also produced an increase in expression of interleukin 1beta, a cytokine known to inhibit the growth of Lu-CSF-1 cells. CsA alone had little or no antiproliferative activity in vitro and did not alter PCL transport. These results indicate that the activity of chemotherapy modulators may extend beyond mitigation of drug resistance to enhancement of therapeutic efficacy against drug-sensitive tumor cells in vitro and in vivo.

Microtubule-dependent multilobular organization of the nucleus in sensitive and multidrug-resistant L0 leukemia cells

The relationship between the nuclear morphology and the microtubular organization of L100 and L1000 cells, two vincristine-induced multidrug resistant human acute lymphocytic leukemia cell lines, was examined and compared to that of L0 parental cells. The L0 parental cells contained a round nucleus and the microtubules were evenly distributed throughout the cytoplasm. In contrast, the microtubules of the L100 and L1000 cells were localized between the lobular structures of a multilobulated nucleus. Disassembly of microtubules in L100 and L1000 cells by colchicine resulted in the loss of the multilobulated morphology of the nucleus. While the total cellular content of tubulin of L0 and L100 cells was similar, the content of microtubules of L100 cells was only 55% of that observed in L0 cells. Two, 28 kDa (pI 6.9) and 31 kDa (pI 4.4), microtubule-associated proteins were found to be overexpressed in L100 and L1000 cells. The results indicate that the multilobulated nuclear morphology of L100 and L1000 cells is dependent upon the unique and intact organization of the microtubules; the distinct organization of the microtubules and the multilobular nuclear morphology of the two resistant cell lines may be due to the differential expression of specific microtubule-associated proteins.

Cyclosporin A/VP-16 produced immunity to L1210 leukemia: the participation of cytotoxic CD8 T-lymphocytes

The role of the immune response in the chemotherapeutic cure of an intact host with neoplasia is not well defined. We have previously shown that the addition of cyclosporin A to VP-16 therapy of BDF/1 mice with L1210 leukemia produces immunity to leukemia in long-surviving host animals. We now characterize this immunity as being tumor specific and related to the participation of CD8 T-lymphocytes. Splenocytes derived from L1210 leukemia immune mice are cytotoxic to L1210 cells after in vitro restimulation, compared to splenocytes harvested from nonimmune control mice. This cytotoxicity is lost by CD8 T-lymphocyte depletion and persists in Ia antigen blocking experiments. Cytotoxicity is selective for L1210 leukemia compared to P388 leukemia, an alternate Ia antigen expressing methylcholanthrine-induced acute lymphoid leukemia, and L1210 leukemia-immune mice remain susceptible to P388 leukemia in vivo demonstrating specificity of the immune response generated by cyclosporin A/VP-16 therapy.

Radioimmunodetection of Hodgkin's disease and non-Hodgkin's lymphomas with monoclonal antibody to eosinophil peroxidase

The purpose of this study was to determine if a radiolabeled murine monoclonal antibody (EOS) directed against eosinophil peroxidase would localize specifically to tumor sites in patients with lymphomas infiltrated by eosinophils. Ten patients with Hodgkin's disease and eosinophilia, three patients with non-Hodgkin's lymphomas and eosinophilia and five control patients received an intravenous injection of 3-10 mg of EOS antibody radiolabeled with 74-155 MBq (2.0-4.2 mCi) of 111In. At intervals of 24, 48 and 72 hr after injection, gamma camera images were obtained along with blood and urine specimens and the imaging results were correlated with the results of other staging modalities. As early as 24 hr after antibody injection, there was clear visualization of identifiable sites of lymphoma with eosinophilia greater than 1 cm in size, including the spleen, bone marrow and lymph nodes. Although EOS also localized nonspecifically to the liver and, in some patients, to the nasopharynx, there was no appreciable uptake in normal bone marrow, spleen, uninvolved lymph nodes, lymphomas without eosinophilia or various other pathologic conditions without eosinophilia. Except for transient pain at tumor sites in three patients, no adverse reactions were noted. We conclude that a radiolabeled monoclonal antibody directed against eosinophil peroxidase localizes to lymphoma sites infiltrated by eosinophils.

Novel nucleolar and nuclear morphology in a vincristine-dependent human leukemia cell line (L100)

Acquired resistance to chemotherapeutic drugs by tumor cells is an important obstacle to effective therapy of human malignancy. We now describe a vincristine (VCR)-induced multidrug-resistant (MDR) human acute lymphatic leukemia cell line, the sustained in vitro growth of which is dependent on vincristine. The doubling time for parental drug-sensitive cells (L0) is 40.2 +/- 13.2 h and for the MDR subline (L100) 62.5 +/- 11.3 h. L100 cells have similar G2 and mitotic phase to parental cells, express the MDR phenotype, and are characterized by novel morphologic features with multilobulated nuclei and multiple small nucleoli. Compared with L0 cells which have 2-3 nucleoli per cell, L100 cells have 7-8 nucleoli per cell. Average nucleolar area is 11.3 +/- 7.3 microns 2 for L0 and 2.5 +/- 2.4 microns 2 for L100 cells determined by the laser scanning method. The striking morphologic abnormalities of L100 cells suggest a drug-induced cytoskeletal abnormality. The relationship of these abnormalities to the VCR growth dependence of L100 cells is discussed.

Cyclosporin A potentiation of VP-16: production of long-term survival in murine acute lymphatic leukemia

Our prior in vitro studies on the correction of multidrug resistance by cyclosporin A (CsA) prompted us to investigate the effect of CsA and VP-16 in vivo. CsA given simultaneously at 2 or 10 mg/kg with VP-16 to BDF/1 mice bearing parental drug-sensitive P388 or L1210 lymphatic leukemia produced a 100% increase in survival as compared with VP-16 treatment alone. CsA-containing regimens also promoted 60-day survival in a significant number of P388 or L1210 leukemia-bearing mice as compared with animals receiving VP-16 in the absence of CsA (P < 0.02 and P < 0.001, respectively). CsA enhancement of the survival of mice bearing these lymphatic leukemias is restricted to VP-16, since the addition of CsA to therapeutic agents such as vincristine, daunorubicin, methotrexate, or cisplatin had no effect on survival.

Synergistic interaction of cyclosporin A and verapamil on vincristine and daunorubicin resistance in multidrug-resistant human leukemia cells in vitro

We studied the effects of cyclosporin A and verapamil on the modulation of vincristine and daunorubicin resistance in a multidrug-resistant subline of human T-cell acute lymphatic leukemia GM3639. Our results show that cyclosporin A is more effective than verapamil as a modulator of the high degree of primary vincristine resistance and the low degree of daunorubicin cross-resistance expressed by this cell line. Isobologram analysis revealed that the combined modulators act synergistically in correcting both vincristine and daunorubicin resistance.

Development of cyclosporin A mediated immunity in L1210 leukaemia

Cyclosporin A (CsA) is an effective modulator of multidrug resistance (MDR) in vitro and in murine tumour systems in vivo. We now report the production of immunity to L1210 leukaemia by the addition of CsA to VP-16 therapy of leukaemic BDF/1 mice. VP-16/cyclosporin A tumour immunity induction arises as a consequence of active therapy independently of immunisation with modified tumour cells. The addition of CsA to VP-16 prolongs survival of BDF/1 host mice bearing L1210 leukaemia beyond that produced by equivalent dose VP-16 alone. A subpopulation of 60-day surviving mice after combined VP-16/CsA are immune to rechallenge with the same leukaemia inoculum to which they were originally exposed. Spleen cells from immune mice adoptively transfer anti-L1210 leukaemia immunity to untreated BDF/1 mice in a dose dependent, statistically significant manner. Adoptive transfer experiments additionally suggest active recruitment of immunologic response in recipient animals: (1) We have been able to perpetuate leukaemia immunity in four sequential cohorts of naive recipient mice. This propogation of adoptive immunity is accomplished by use of spleen cells harvested from each preceeding passively-protected animal cohort; (2) Cyclophosphamide pretreatment of adoptive transfer recipient mice abrogates the ability of their splenocytes to perpetuate passive protection in sequential adoptive transfer experiments.

Cyclosporin A and verapamil enhancement of daunorubicin-produced nucleolar protein B23 translocation in daunorubicin-resistant and -sensitive human and murine tumor cells

It has recently been shown that anthracycline antibiotic-resistant tumor cells are less responsive to daunorubicin-stimulated B23 nucleolar phosphoprotein translocation than drug-sensitive cells. Since cyclosporin A and verapamil reverse primary acquired and secondary cross-resistance to daunorubicin, we investigated the effect of these agents on nucleolar B23 translocation in sensitive and resistant tumors. We compared modified to baseline B23 phosphoprotein distribution between predominantly nucleolar, mixed nucleolar-nuclear, or nuclear immunofluorescence using a monoclonal anti-B23 antibody in parental drug-sensitive and multidrug-resistant acute lymphatic leukemia and in daunorubicin-sensitive and -resistant murine hepatoma. Our experiments show that cyclosporin A and verapamil alone have no effect on B23 phosphoprotein translocation, but that the addition of either agent to sensitive parental or resistant tumor sublines markedly enhances daunorubicin-stimulated translocation. This effect correlates with the correction of impaired daunorubicin inhibition of RNA synthesis by cyclosporin A and verapamil in the resistant sublines. Our observations suggest that nucleolar B23 phosphoprotein is an important site in the modulation of anthracycline antibiotic antitumor activity.

Third trimester chemotherapy and neonatal hematopoiesis

An 18-year-old woman with severe pancytopenia secondary to chemotherapy given in the third trimester of pregnancy and who delivered an infant with normal peripheral blood counts is reported. The literature is reviewed, and recommendations for the method of delivery in this setting are discussed.

Albumin inhibition of the antileukemic activity of hydroxylated phenothiazines

Trifluoperazine (TFP) shows cytotoxic activity against human acute lymphatic leukemia (ALL) in vitro. This activity is inhibited by increasing serum concentration and by albumin. Despite its in vitro activity, the drug is inactive in vivo. To determine if increased phenothiazine hydrophilicity could protect against albumin inhibition of antileukemic activity, we compared ALL cytotoxic median effective dose concentrations of a series of hydroxylated phenothiazines in 5% fetal bovine serum (FBS) and in 5% FBS supplemented with albumin. Albumin inhibits the activity of all drugs. A representative derivative 7,8-dihydroxychlorpromazine, although active in vitro, is inactive against L1210 and P388 murine leukemias in vivo.

Cyclosporin A corrects daunorubicin resistance in Ehrlich ascites carcinoma

We have previously developed a daunorubicin resistant subline of Ehrlich ascites carcinoma (EA/DR) for studies on the reversal of daunorubicin resistance. The mean survival of untreated BALB/c mice bearing drug sensitive parental tumour (EA/DS) is 18.4 +/- 0.6 days, mice bearing EA/DS treated with five daily doses of 0.3 mg kg-1 daunorubicin greater than 60 days, and mice bearing EA/DR treated with the same daunorubicin regimen, 21.1 +/- 1.4 days. We now report complete reversal of daunorubicin resistance in EA/DR by cyclosporin A (CsA). The in vitro daunorubicin IC50, defined as that concentration of daunorubicin required to inhibit 50% of DNA synthesis, in EA/DR was 6.7 +/- 1.15 micrograms ml-1 compared to 2.8 +/- 0.72 micrograms ml-1 in EA/DS. This value was reduced to 2.8 +/- 0.52 and 2.1 +/- 0.10 micrograms ml-1 daunorubicin by 3.3 and 13.2 micrograms ml-1 CsA respectively, P less than 0.05. The MST of groups of host mice bearing EA/DR either untreated, treated with five daily doses of 0.3 mg kg-1 daunorubicin, treated with 80 mg kg-1 CsA in five divided daily doses or treated with combined daunorubicin-CsA were 19.0 +/- 1.0, 21.1 +/- 1.4, 24.0 +/- 2.6 and greater than 60 days respectively. The mean survival of groups of host mice bearing EA/DR treated with 5 mg kg-1 or 10 mg kg-1 CsA simultaneously with daunorubicin for five days was also greater than 60 days. These differences are highly significant.

Cyclosporin A reverses vincristine and daunorubicin resistance in acute lymphatic leukemia in vitro

The development of drug resistance by tumor cells is a major obstacle to the cure of human malignancy. Cyclosporin A (CsA) completely reverses primary resistance to vincristine and cross resistance to daunorubicin in a pleiotropic drug-resistant subline of human T cell acute lymphatic leukemia. This subline is over 50-fold resistant to vincristine and fivefold resistant to daunorubicin. CsA has little effect on vincristine or daunorubicin activity in drug-sensitive parental leukemia and corrects daunorubicin resistance without altering cellular daunorubicin accumulation.

Verapamil potentiation of VP-16-213 in acute lymphatic leukemia and reversal of pleiotropic drug resistance

Verapamil, the calcium-influx-blocking agent, has previously been shown to have favorable interactions with antineoplastic drugs. Our study of human T cell acute lymphatic leukemia (ALL) GM3639 indicates that verapamil enhances the in vitro cytotoxicity of VP-16-213 against drug-sensitive ALL by reducing the concentration of VP-16-213, resulting in 50% cell viability from 104.5 +/- 26.6 nM to 46.0 +/- 2.7 nM (P less than 0.05). The addition of verapamil to VP-16-213 treatment of BDF/1 mice bearing L1210 leukemia increases their mean survival from 21.2 +/- 3.6 to 50.4 +/- 4.3 days (P less than 0.01) and the survival of CD2F/l mice bearing P388 leukemia from 27.8 +/- 3.7 to 49.1 +/- 5.0 days (P less than 0.01). The 30-day survival is significantly increased in L1210 and P388 leukemia mice, and 60-day survival is significantly increased in P388 leukemic mice by verapamil. We developed a vincristine (VCR)-resistant subline of GM3639 T cell ALL, L23, by continuous exposure of drug-sensitive cells to VCR. This subline demonstrates pleiotropic cross resistance to VP-16-213 and daunorubicin. The addition of verapamil to VCR, to VP-16-213, and to daunorubicin completely restores responsiveness to these drugs, as indicated by the normalization of the VCR and VP-16-213 concentrations required for cytotoxicity and the concentration of daunorubicin required for inhibition of thymidine incorporation.

Mondor's disease associated with metastatic axillary nodes

Mondor's disease, superficial thrombophlebitis of the breast, is customarily associated with benign conditions of the breast. This article reports a patient in whom an early manifestation of recurrent axillary metastasis from carcinoma of the breast was a symptom of ipsilateral superficial thrombophlebitis of the breast, an unusual association.

Aplastic anemia occurring as amegakaryocytic thrombocytopenia with and without an inhibitor of granulopoiesis

Two patients with aplastic anemia evolving from cellular bone marrows with severely diminished megakaryocytes are reported. During this evolution a plasma inhibitor of in vitro granulocyte-macrophage colony formation was demonstrated associated with non-A, non-B hepatitis in one patient. The second patient had abnormal liver function that corrected after the delivery of a normal newborn but there was persistence of pancytopenia without evidence of a plasma inhibitor.

Effect of antineoplastic agents on gamma-interferon production in human peripheral blood mononuclear cells

Since gamma-interferon (IFN-gamma) is a potent immunomodulator and patients receiving certain antineoplastic agents are at risk of unusual infections, we have determined the effect of certain antineoplastic agents on IFN-gamma production. Induction of peripheral blood mononuclear cells from normal donors in the presence and absence of various antineoplastic agents was achieved using phytohemagglutinin (8 micrograms/ml). Supernatants were then separated by centrifugation, dialyzed, and assayed for interferon. Cell viability was always greater than 85% with or without the presence of drugs. Hydrocortisone was found to eliminate IFN-gamma production if added within 24 hr after the phytohemagglutinin. The suppression of IFN-gamma production occurred with hydrocortisone concentrations as low as 0.65 microgram/ml, was associated with a diminished proliferative response to the lectin, and occurred with other interferon inducers including staphylococcal enterotoxin A. Adriamycin (0.4 microgram/ml) and vincristine (0.08 microgram/ml) also diminished IFN-gamma production, but only if the peripheral blood mononuclear cells were pretreated with the drugs. Methotrexate, 5-fluorouracil, and 6-mercaptopurine failed to influence the yield of IFN-gamma. These results are significantly different from experiments previously reported using alpha- and beta-interferons and suggest an important mechanism by which these drugs can produce immunosuppression.

CNS infection and bacteremia due to clostridium septicum

Central nervous system infection with Clostridium septicum is rare. We report two fulminant cases of such infection with accompanying bacteremia. The presence of extensive brain necrosis was striking in our two cases. The association of C septicum bacteremia with hematologic disease, and with solid tumors, was present in our cases. We conclude that C septicum should be considered as a potential cause of life-threatening bacteremia and meningitis in the compromised host.

Calcium modifies the accumulation and retention of daunorubicin by Ehrlich ascites carcinoma

Verapamil restores daunorubicin sensitivity to daunorubicin resistant Ehrlich ascites carcinoma but is without effect when used with daunorubicin in daunorubicin sensitive parental Ehrlich ascites tumor. Energy dependent daunorubicin efflux is more active in drug resistant than in drug sensitive cells. However, daunorubicin retention decreases equivalently in drug resistant and sensitive cells with increasing calcium levels in the presence of both intact and interrupted outward transport. Therefore, (1) daunorubicin accumulation and retention in Ehrlich ascites carcinoma cells is influenced by at least two independent mechanisms and (2) it is likely that verapamil modifies daunorubicin activity in drug resistant tumor variants by mechanisms beyond calcium inhibition.

Inhibition of interferon yield by vincristine

Vincristine has been shown in vitro to adversely influence the interferon system. In order to further investigate the effects of vincristine on interferon production, we determined the dose of vincristine and the duration of time required to diminish Newcastle Disease Virus-induced human leukocyte interferon production in vitro. Further, mice were treated with vincristine and induced to produce interferon using 10-carboxymethyl-9-acridanone. The concentration required to diminish interferon yields was the very highest found in man during therapy. The duration of exposure to vincristine (at the highest concentration) required to influence interferon production far exceeded the duration this concentration persists in serum during therapy. Furthermore, the mouse model failed to show any diminished interferon producing capacity for vincristine treated mice. We conclude that while vincristine can clearly diminish interferon yields, current treatment regimens using vincristine probably do not alter interferon production. The mechanism by which vincristine influences interferon yields in vitro appears to be by a direct effect on the ability of the cell to produce interferon.

Verapamil restoration of daunorubicin responsiveness in daunorubicin-resistant Ehrlich ascites carcinoma

We have studied the influence of verapamil hydrochloride on the in vitro and in vivo effects of daunorubicin in Ehrlich ascites carcinoma. Daunorubicin-sensitive tumor was rendered resistant to daunorubicin by the continuous treatment of sequential generations of tumor-bearing BALB/c mice. The ability of daunorubicin to inhibit [(3)H]uridine and [(3)H]thymidine incorporation and the effect of daunorubicin on the mean survival time of host animals bearing daunorubicin-sensitive and daunorubicin-resistant Ehrlich ascites carcinoma were compared. The addition of verapamil to daunorubicin in vitro reduced the concentration of daunorubicin required to inhibit 50% of DNA and RNA synthesis in the daunorubicin-resistant tumor to that required in the daunorubicin-sensitive tumor, from 6 and 4.4 mug/ml to 1.5 and 1.3 mug/ml, respectively. Verapamil also restored drug sensitivity to daunorubicin-resistant Ehrlich ascites carcinoma in vivo. The 21.7+/-0.7 d mean survival time (MST) of BALB/c mice bearing daunorubicin-resistant tumor treated with daunorubicin alone rose to 44.0+/-0.7 d when the same tumor was treated with verapamil and daunorubicin, P < 0.001. This in vivo effect is specific for daunorubicin-resistant Ehrlich ascites carcinoma, since there is no alteration in MST of BALB/c mice bearing daunorubicin-sensitive or daunorubicin-resistant tumor when they are treated with verapamil alone or when BALB/c mice bearing daunorubicin-sensitive tumor are treated with daunorubicin and verapamil.

Activated partial thromboplastin time after heparin removal (aPTT/HR) in a new scheme of anticoagulant monitoring

Activated partial thromboplastin time after heparin removal (aPTT/HR), a test employing anion exchange chromatography, was devised as an alternative to the prothrombin time after heparin removal (PT/HR) to monitor simultaneous anticoagulation with heparin and coumarins. The potential utility of the aPTT/HR was assessed by performing parallel PTs and aPTTs on 62 consecutive plasmas from coumarin-treated outpatients. All samples had 0.2 units/ml of heparin added and then removed to see if the maneuver influenced therapeutic group assignment. In no instance did reassignment occur. A conditional Irwin-Fisher test (P = 0.000604) and a special multinomial trial analysis (P = 0.002) indicated that the aPTT would be at least comparable to the PT for following coumarin antithrombotic prophylaxis. Since the heparin removal procedure had no influence on therapeutic categorization, the same statistical proof could be applied to the relationship between aPTT/HR and PT/HR. This study indicates that the aPTT can be used to monitor all stages of heparin and /or coumarin anticoagulation.

Adult nephrotic syndrome and acquired coagulopathies: Hageman factor deficiency

Analysis of tests of coagulation and fibrinolysis from 20 adult nephrotics prior to the onset of therapy disclosed that 40 percent had low factor XII levels. The mean factor XI was normal. The platelet count and fibrinogen concentration were elevated. The findings of this study on adults are similar to those of Honig and Lindley(21) in the nephrotic syndrome of childhood. Subjects with minimal change disease constituted a small (15 percent) but readily segregated subpopulation without evidence of fibrinolysis in association with low factor XII activity. Prolongation of the activated partial thromboplastin time corresponded in every instance with factor XII activities of ≤30 percent. Lengthening of the one stage prothrombin time was not directly attributable to factor deficiencies.

Doxorubicin-hexamethylmelamine therapy of small cell carcinoma of the lung

Eighteen patients with small cell carcinoma of the lung treated with doxorubicin hydrochloride and hexamethylmelamine are presented. Fifteen of these patients had extensive disease at presentation. Four patients in this group died after one or fewer courses of chemotherapy. The median duration of survival for the entire group of patients is 15 months. Six patients are alive from 18 to 56 months without evidence of disease. Drug toxicity was minimal and well tolerated, which permitted this regimen to be given in an outpatient setting.

Combined interferon--antimetabolite therapy of murine L1210 leukemia

To assess the interaction of interferon with estabished chemotherapeutic agents, L1210 murine leukemia in BDF/1 mice was treated with methotrexate, 6-mercaptopurine. Adriamycin, cytosine arabinoside or cyclophosphamide alone or in combination with mouse L-cell (Newcastle disease virus-induced) interferon or with interferon-free tissue culture medium. Also studied was the effect of interferon on the combined 6-mercaptopurine-methotrexate therapy of this tumor. Interferon failed to enhance the response of L1210 leukemia to 6-mercaptopurine, adriamycin, cytosine arabinoside or cyclophosphamide. The addition of interferon to all methotrexate-containing regimens increased mean survival time (P less than 0.05). The increase in survival of host animals treated with 6-mercaptopurine-methotrexate and interferon was sustained though four transfer generations despite evolving resistance to this antimetabolite combination.

Lymphocytotoxic anti-LewisbH antibody

We wish to report strong lymphocyte crossmatch incompatibility attributable to anti-Lea antibody. The prospective renal transplant recipient was Le(a-b-) and her serum contained potent anti-Lea and anti-LebH antibodies. Despite the fact that were able to demonstrate greater B lymphocyte than T lymphocyte Lewis(a+) antigenicity, this serum was capable of causing greater than 80% cytotoxicity of Le(a+) and Le(b+)O or A2 whole lymphocyte populations. Antibody activity was completely inhibited by Lewis substance. This inhibition was specific and did not interfere with HLA antibody activity.

Successful pregnancy during chemotherapy for acute leukemia

A 26-year-old patient with acute lymphatic leukemic conceived while on systemic chemotherapy. This patient experienced relapse during the second trimester, and a second complete hematologic remission was achieved with doxorubicin hydrochloride, vincristine, and prednisone. A 2400-gram, but otherwise normal, male infant was delivered by Caesarean section during the 36th gestational week. Growth and development of this child is normal at six months.

In vivo and in vitro cell-mediated immunity to tetanus toxoid in adults

The purpose of this study was to evaluate tetanus toxoid (TT) as an indicator of cutaneous delayed hypersensitivity (CDH) in adults. Fifty-two normal subjects, aged 25 to 64 yr, were skin tested with TT and streptokinase-streptodornase (SK/SD). Lymphocyte transformation was studied in seven normal TT reactors, four normal TT nonreactors, and seven hospitalized anergic patients. CDH was common with both TT and SK/SD; 90% of the adults, aged 25 to 39 yr, had CDH reactions to TT and 79% had CDH reactions to SK/SD. In adults aged 40 to 64 yr, 75% had DCH reactions to TT and 59% had CDH reactions to SK/SD. Lymphocyte transformation to TT correlated well with TT skin-test results. Punch biopsy specimens of TT reactions 48 hr after skin testing demonstrated DCH. We conclude that TT is an excellent antigen for assessing the presence or absence of CDH in adults aged 25 to 64 yr.

Multiple myeloma complicated by myelomatous obstructive uropathy

Two patients with multiple myeloma with large retroperitoneal myelomatous masses are discussed. This extraosseous extension of disease caused obstructive uropathy in both patients. This complication has not been previously recognized in multiple myeloma and must be added to the potential casues of renal failure in this disease.

Decreased incidence of HLA-A11 and increased incidence of HLA-B8 in a North American population of insulin dependent diabetics

Seventy-four North American Caucasian insulin dependent diabetics are presented and compared to 100 healthy controls relative to HLA-A and B locus antigens. A highly significant increase in the frequency of HLA-B8 was found (p < 0.01, relative risk 3.67). The presence of HLA-A11 conferred statistically significant protection against disease development in these patients (p < 0.01, relative risk 0.19). There was no significant difference in the frequency of HLA-B7, B8, or B15 between the study and control groups. The patient group does show a significant increase in heterozygosity for HLA-B8 and HLA-B15 when compared to healthy controls (p < 0.05, relative risk 7.17). Increased incidence of HLA-B18 has previously been noted in French and English populations only. Since most of our HLA-B18 patients are of English extraction, it is concluded tht the altered incidence of the HLA-B18 allele in insulin dependent diabetes does persist in this migratory European population.

Dissimilar effects of ultraviolet light on HLA-D and HLA-DR antigens

Since HLA-DR antigens are closely related to HLA-D antigens, we studied the effect of low-dose ultraviolet irradiation on the ability of human lymphocytes to induce a proliferative response in mixed lymphocyte culture (HLA-D) and on the serologic reactivity of B lymphocyte HLA-DR antigens. We found (1) no alteration in the serologic definition of DR antigens despite the abrogation of the induction of proliferative responses in mixed lymphocyte culture, (2) no evidence that ultraviolet light (UVL) stimulated suppressor cells contributed to the loss of allostimulation, and (3) no evidence that the abrogation of the induction of proliferative responses could be modified by increasing the number of UVL exposed lymphocytes in mixed lymphocyte culture. These findings suggest that HLA-D and HLA-DR antigens are different molecularly, but are also consistent with the concept that certain active metabolic processes are required of stimulator cells for allostimulation and that these processes are UVL sensitive.

Immunological suppressor cell activity in insulin dependent diabetes

We have measured suppressor activity of the peripheral blood lymphocytes and monocytes from 13 insulin dependent diabetics with established disease for two or more years. A statistically significant increase in suppressor T-lymphocyte activity was demonstrated in patients who had a positive response in this assay. There was no alteration in the activity of prostaglandin synthetase dependent mononuclear cell activity. There was no correlation of lymphocyte suppressor activity with HLA type of these patients. These results may contribute to the understanding of the propensity for infection in patients with insulin dependent diabetes.

Diminished antiviral effect of human interferon in the presence of therapeutic concentrations of antineoplastic agents

Antiviral activity of human interferon has been found to be diminished in the presence of therapeutic concentrations of certain drugs used to treat neoplastic diseases.

Long-term survivors of high-grade malignant astrocytomas

This report descibes our experience with 40 evaluable patients with high-grade malignant astrocytomas. Eleven patients were treated with surgery and radiotherapy; 29 patients were treated with surgery, radiotherapy, and BCNU chemotherapy. Ten of these 29 patients are two-year survivors. Their mean survival is over 57.3 months, and they have been off chemotherapy for one to 27 months, mean 13.7 months. Seven of these patients received 800 to 1,100 mg/m2 of BCNU; three other long survivors received greater amounts of BCNU. Our current recommendation is that patients with high-grade malignant astrocytomas be treated with surgery, radiotherapy, and at least 800 mg/m2 of BCNU.

Remission of pure red cell aplasia associated with nonthymic malignancy

Two patients with acquired pure red cell aplasia associated with malignancy are presented. One patient has breast cancer and the other had poorly differentiated nodular lymphoma; neither patient had evidence of a serum inhibitor of hemoglobin synthesis and both achieved complete hematologic remission following prolonged immunosuppressive therapy. The literature describing the association of pure red cell aplasia and nonthymic malignancy is reviewed and potential for responsiveness discussed.

Prothrombin time after heparin removal. Application to monitoring simultaneous anticoagulation with heparin and coumarins

Coumarin-anticoagulated plasmas from 31 subjects comprising two study groups were passed through epichlorohydrin triethanolamine cellulose (ECTEOLA) chromatography columns. Group I plasmas, which were run with nothing added, had mean prothrombin times of 21.6 +/- 5.4 sec prior to and 22.4 +/- 5.6 sec following exposure to these columns (r = 0.9449; t = 1.8307, P less than 0.100). The mean prothrombin time for Group II, 18.2 +/- 4.9 sec, lengthened with 5 u/ml heparin to 35.5 +/- 16.2 sec, and returned to 19.2 +/- 5.0 (r = 0.9763) after chromatography. Therefore, it appears that coumarin anticoagulation had no significant influence upon the capacity of ECTEOLA effectively to remove heparin in therapeutic doses. This means that virtually all prothrombin time reagent systems can be employed to monitor concurrent heparin and coumarin anticoagulation. In addition, quality control of the combined technic is simpler, and the technic more sensitive to low levels of fibrinogen and factor V.

Septicemia in acute leukemia

We have surveyed septicemic episodes occuring in individuals with acute leukemia and have found two factors favorably influencing survival, mainly granulocyte counts over 1,000 mm3 and gram-positive bacteremias. In contrast, blood cultures persistently positive for longer than 48 hours were a bad prognosticator. Significantly, patients with gram-positive bacteremia had received less antibiotics in the week prior to septicemia than had patients with gram-negative bacteremia.