Effects of interleukin-1 and interleukin-1 receptor antagonist in AIDS-Kaposi's sarcoma

Cytokine/Chemokine responses in activated CD4+ and CD8+ T cells isolated from peripheral blood, bone marrow, and axillary lymph nodes during acute simian immunodeficiency virus infection

Understanding the cytokine/chemokine networks in CD4(+) and CD8(+) T cells during the acute phase of infection is crucial to design therapies for the control of early human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) replication. Here, we measured early changes in CD4(+) and CD8(+) T cells in the peripheral blood (PB), bone marrow (BM), and axillary lymph node (ALN) tissue of rhesus macaques infected with SIVMAC251. At 21 days after infection, all tissues showed a statistically significant loss of CD4(+) T cells along with immune activation of CD8(+) T cells in PB and ALN tissue. Twenty-eight different cytokines/chemokines were quantified in either anti-CD3/28 antibody- or staphylococcal enterotoxin B-stimulated single-positive CD4(+) and CD8(+) T cells. PB CD4(+) T cells produced predominantly interleukin-2 (IL-2), whereas CD4(+) and CD8(+) T-cell subsets in tissues produced β-chemokines both before and 21 days after SIV infection. Tissues generally exhibited massive upregulation of many cytokines/chemokines following infection, possibly in an attempt to mitigate the loss of CD4(+) T cells. There was no evidence of a T-helper 1 (TH1)-to-TH2 shift in CD4(+) T cells or a T-cytotoxic 1 (TC1)-to-TC2 cytokine shift in CD8(+) T cells in PB, BM, and ALN T-cell subsets during the acute phase of SIV infection. Despite the upregulation of several important effector cytokines/chemokines (IL-2, IL-12, IL-17, gamma interferon, granulocyte-macrophage colony-stimulating factor) by CD4(+) and CD8(+) T cells, upregulation of β-chemokines (CCL2 and CCL22), basic fibroblast growth factor (FGF-basic), hepatocyte growth factor (HGF), and migration inhibition factor (MIF) may provide a poor prognosis either by inducing increased virus replication or by other unknown mechanisms. Therefore, drugs targeting β-chemokines (CCL2 and CCL22), FGF-basic, HGF, or MIF might be important for developing effective vaccines and therapeutics against HIV.

IMPORTANCE

Human immunodeficiency virus (HIV)/simian immunodeficiency virus (SIV) infection results in early depletion of CD4(+) T cells and dysregulation of protective immune responses. Therefore, understanding the cytokine/chemokine networks in CD4(+) and CD8(+) T cells in different tissues during the acute phase of infection is crucial to the design of therapies for the control of early viral replication. Here, we measured early changes in CD4(+) and CD8(+) T cells in peripheral blood (PB), bone marrow (BM), and axillary lymph node (ALN) tissue of rhesus macaques infected with SIVMAC251. There was no evidence of a T-helper 1 (TH1)-to-TH2 shift in CD4(+) T cells or a T-cytotoxic 1 (TC1)-to-TC2 cytokine shift in CD8(+) T cells in PB, BM, and ALN T-cell subsets during the acute phase of SIV infection. Despite the upregulation of several important effector cytokines/chemokines by CD4(+) and CD8(+) T cells, upregulation of β-chemokines, fibroblast growth factor-basic, hepatocyte growth factor, and migration inhibition factor may provide a poor prognosis.

Therapy of AIDS-associated Kaposi's sarcoma: targeting pathogenetic mechanisms

Only a small number of the many agents with the potential to inhibit factors known to stimulate KS growth have been tested clinically, and many were investigated at a time when treatment options for HIV infection were relatively ineffective. The failure of some of these agents to induce KS regression may not signify failure to achieve a relevant biologic effect in all cases, but may simply mean that in a neoplasm that expresses a broad array of growth factors, inhibition of a single factor may be insufficient to achieve tumor regression. Moreover, agents that inhibit angiogenesis may be expected to stabilize tumors rather then eradicate them, but tumor stabilization is a difficult endpoint to quantify. In fact, given the redundancy of growth factors believed to be involved in KS development, it is perhaps remarkable that members of several classes of agents (eg, a synthetic retinoid, an MMPI, thalidomide, IL-12) have induced KS regression in a substantial minority of patients. It is likely, however, that drug combinations that target several pathogenetic mechanisms will be more effective than will single drugs in suppressing KS growth. A particular need. especially in the early evaluation of therapies aimed at specific pathogenic targets, is the development of assays to measure specific biologic effects (eg, changes in the activity of signal transduction pathways within tumor biopsy specimens) related to the agent's putative mechanism of action. Greater availability and clinical application of these types of markers of biologic efficacy may speed the identification of potentially active agents that could then be "fast tracked" into larger efficacy trials and combination studies.

Interleukin-1 beta increases the BCL-2/BAX ratio in Kaposi's sarcoma cells

Interleukin-1 (IL-1) is a multifunctional cytokine known to act as a growth factor for AIDS-KS cells. In addition to its mitogenic effects, we found that IL-1 induced the protection of KS cells from apoptotic death induced by serum deprivation in a dose-dependent manner. AIDS-KS cells as well as cells derived from iatrogenic and sporadic KS exhibited a similar response to IL-1, which stresses the key role of this cytokine in the pathogenesis of KS regardless of its epidemiological form. Using both an immunohistochemical and an immunoblot approach, we found that IL-1 increased the expression of Bcl-2 and decreased that of Bax, while having no effect on the expression of Bclx(L), Fas and CD40. The effects of IL-1 were inhibited by IL-1ra, suggesting that imbalance between these two counter-acting cytokines may contribute to the altered accumulation of KS spindle cells. Our findings may provide a link between KS cell escape from apoptosis and the immune dysregulation known to be associated with KS.

Contradictory Concepts in the Etiology and Regression of Kaposi's Sarcoma. The Ferenc Györkey Memorial Lecture

The Introduction is an overview of 3 decades of works performed by Professor Ferenc Györkey (in many cases in collaboration with the author) and aimed at the elucidation of viral participation in the etiology of arteriosclerosis, SLE, hairy cell leukemia, HD, AIDS and KS. Controversial issues surrounding the etiology, treatment and regression of KS are discussed in terms of paracrine and autocrine loops of growth factors; protooncogene-oncogene activations, immunosuppression and retro- and/or herpesviral etiology. In regressing KS lesions the roles played by Fas, Bcl-2, Bax, TNFß; apoptotic-antiapoptotic events; and antiangiogenesis agents especially that of Hu-r-IFNa are elaborated on.

An IL6 promoter polymorphism is associated with a lifetime risk of development of Kaposi sarcoma in men infected with human immunodeficiency virus

Kaposi sarcoma (KS) is an angioproliferative inflammatory condition that occurs commonly in patients infected with human immunodeficiency virus (HIV). Inflammatory cytokines and growth factors promote the development of KS. Because physiologically important cytokine polymorphisms modulate host inflammatory responses, we investigated the association between KS and common regulatory polymorphisms in 5 proinflammatory cytokine genes encoding interleukin (IL) IL-1α, IL-1β, tumor necrosis factor (TNF) α, TNF-β, and IL-6 and in the IL-1 receptor antagonist (IL1RN). We also examined the contribution of stromal-derived factor 1 and chemokine receptor 5 (Δ32) polymorphisms to KS development. The population consisted of 115 HIV-infected men with KS and 126 deceased HIV-infected men without KS. The only strong association was observed between an IL6promoter polymorphism (G-174C) and susceptibility to KS in HIV-infected men (P = .0035). Homozygotes for IL6 allele G, associated with increased IL6 production, were overrepresented among patients with KS (P = .0046), whereas allele C homozygotes were underrepresented (P = .0062). Substantial in vitro evidence indicates that IL-6 contributes to the pathogenesis of KS. Our results show thatIL6 promoter genotypes associated with altered gene expression are risk factors for development of KS. Identification of a genetic risk factor for development of KS has important clinical implications for prevention and therapy.

An IL6 promoter polymorphism is associated with a lifetime risk of development of Kaposi sarcoma in men infected with human immunodeficiency virus

Kaposi sarcoma (KS) is an angioproliferative inflammatory condition that occurs commonly in patients infected with human immunodeficiency virus (HIV). Inflammatory cytokines and growth factors promote the development of KS. Because physiologically important cytokine polymorphisms modulate host inflammatory responses, we investigated the association between KS and common regulatory polymorphisms in 5 proinflammatory cytokine genes encoding interleukin (IL) IL-1α, IL-1β, tumor necrosis factor (TNF) α, TNF-β, and IL-6 and in the IL-1 receptor antagonist (IL1RN). We also examined the contribution of stromal-derived factor 1 and chemokine receptor 5 (Δ32) polymorphisms to KS development. The population consisted of 115 HIV-infected men with KS and 126 deceased HIV-infected men without KS. The only strong association was observed between an IL6promoter polymorphism (G-174C) and susceptibility to KS in HIV-infected men (P = .0035). Homozygotes for IL6 allele G, associated with increased IL6 production, were overrepresented among patients with KS (P = .0046), whereas allele C homozygotes were underrepresented (P = .0062). Substantial in vitro evidence indicates that IL-6 contributes to the pathogenesis of KS. Our results show thatIL6 promoter genotypes associated with altered gene expression are risk factors for development of KS. Identification of a genetic risk factor for development of KS has important clinical implications for prevention and therapy.

Interleukin-1 receptor antagonist as a treatment of HIV infection

The human immunodeficiency virus (HIV) apparently utilizes human chromosome 2, interleukin-1 (IL-1), glucocorticoid hormones, and viral Tat protein to accelerate its replication and the synthesis of all HIV proteins. HIV Tat protein binds to the long terminal repeat (LTR) ribonucleic acid, including the trans-acting responsive (TAR) sequence and the promoter region to increase HIV replication. Tat-TAR transactivation requires a factor encoded on the long arm of chromosome 2. The interaction of HIV with chromosome 2 may also cause the observed inhibition of interleukin-1 receptor antagonist (IL-1RA), thus increasing the production of IL-1. IL-1, in turn, stimulates the HIV-1 enhancer region of the LTR, thus increasing HIV gene expression and replication. IL-1 also induces glucocorticoid hormone synthesis which stimulates HIV in the virion infectivity factor (Vif) region, thus increasing HIV infectivity. It is, thus, proposed that IL-1RA not only may serve to inhibit HIV-induced IL-1, but may be the unidentified human chorionic gonadotropin-associated factor recently found to have anti-HIV and anti-Kaposi's sarcoma activity.

Results of a randomized study of IM862 nasal solution in the treatment of AIDS-related Kaposi's sarcoma

PURPOSE

Although advances have been made in the treatment of AIDS-related Kaposi's sarcoma (AIDS-KS) with systemic chemotherapy, less toxic therapies are needed. IM862 is a naturally occurring peptide with antiangiogenic properties and was thus studied in patients with AIDS-KS.

PATIENTS AND METHODS

IM862 was given as intranasal drops at a dose of 5 mg. Patients were randomized to two dosing schedules given in repeated cycles until disease progression or unacceptable toxicity: 5 days of therapy followed by 5 days off (n = 18) and every other day dosing (n = 26).

RESULTS

Forty-two male patients and two female patients with a median age of 38 years (range, 22 to 53 years) were accrued. Twenty-one patients (47%) had more than 50 mucocutaneous lesions, 14 (32%) had lymphedema, and none had visceral involvement. Thirty-three patients (75%) had received prior systemic chemotherapy. Twenty-four patients (55%) had CD4(+) lymphocyte count </= 200/mm(3). All but five patients were being treated with concurrent protease inhibitor(s), for a median of 10 months (range, 0 to 24 months). Major responses were documented in 36%, with five complete and 11 partial remissions, occurring after a median of 6 weeks (range, 3 to 26 weeks) and lasting a median of 33+ weeks (range, 12+ to 95+ weeks). Twenty-one patients had stable disease for periods of 7 to 72+ weeks. Adverse effects to IM862 were limited to mild and transient headache, fatigue, tingling, and nausea. No hematologic adverse effects attributed to treatment were reported.

CONCLUSION

IM862 given as intranasal drops is well tolerated and has antitumor activity in patients with AIDS-KS. A randomized double-blinded study to define the activity of IM862 in patients with AIDS-KS is in progress.

Interleukin-4 receptor-directed cytotoxin therapy of AIDS-associated Kaposi's sarcoma tumors in xenograft model

The elusive and enigmatic origin of AIDS-associated Kaposi's sarcoma (AIDS-KS) makes it a complex tumor and therefore difficult to treat. Here we demonstrate that AIDS-KS cells express surface interleukin-4 (IL-4) receptors, and that IL-4 toxin (IL-4(38-37)-PE38KDEL) is specifically cytotoxic to these cells. Intratumoral, intraperitoneal and intravenous administration of IL-4 toxin in nude mice with established subcutaneous AIDS-KS tumors caused considerable anti-tumor activity in a dose-dependent manner, with highest dose producing durable complete responses. Metabolic changes, including cachexia and lymphopenia, induced by KS tumors were prevented by IL-4 toxin treatment. This report establishes IL-4(38-37)-PE38KDEL as an experimental therapeutic agent for the treatment of AIDS-KS.

Phase I/II trial of the type I soluble recombinant human interleukin-1 receptor in HIV-1-infected patients

Interleukin-1 (IL-1) produced in peripheral blood mononuclear cell (PBMC) cultures or added exogenously has been shown to upregulate HIV expression in vitro. Inhibition of IL-1 in HIV-infected individuals may inhibit HIV activation and slow disease progression. Recombinant human IL-1 receptor (rHu-IL-1R), the soluble extracellular portion of the human type I IL-1 receptor, inhibits HIV expression in acutely infected primary PBMCs and in the chronically infected promonocytic cell line, U1. We, therefore, conducted a phase I/II trial of the soluble rHu-IL-1R in HIV-1-infected individuals with CD4 T cell counts <300/microl to evaluate its safety and activity. Twelve evaluable patients were enrolled at three rHu-IL-1R dose levels:125 (n=3), 500 (n=3), and 1250 (n=6) microg/m2 per dose by subcutaneous (s.c.) injection three times a week for 8 weeks, followed by a 4 week observation period. rHu-IL-1R was safe and well tolerated. There were no deaths, no treatment-related grade 3/4 events, and no premature study discontinuations because of adverse events. The maximum tolerated dose was not reached. Seven patients reported improvements in one or more symptoms, including weight gain (3), improved energy level (4), decreased diarrhea (1), decreased night sweats (1), improvement in psoriatic arthritis (1), and improvement in a nonspecific chronic diffuse skin rash (1). Of 3 evaluable patients with Kaposi's sarcoma, 1 remained stable and 2 showed minimal progression. No consistent trends in absolute CD4 counts or percentages, quantitative HIV cultures, or serum p24 antigen, beta2-microglobulin, or triglyceride levels were observed. rHu-IL-1R is safe and well tolerated at the doses tested but induced no consistent changes in objective markers of HIV disease. Symptomatic improvements will require confirmation in randomized, placebo-controlled trials.

Induction of interleukin-1 and glucocorticoid hormones by HIV promotes viral replication and links human chromosome 2 to AIDS pathogenesis: genetic mechanisms and therapeutic implications

Human immunodeficiency virus may regulate its replication by stimulating the synthesis of interleukin-1. Interleukin-1, in turn, has the ability to stimulate the human immunodeficiency virus enhancer region. The human genes responsible for interleukin-1 and interleukin-1 receptor antagonist synthesis are located on the long arm of chromosome 2. Coincidentally, the trans-activation responsive ribonucleic acid element in the R region of the long terminal repeat of human immunodeficiency virus-1 has been found to interact directly with a factor present on the long arm of chromosome 2 to facilitate transactivation by the human immunodeficiency virus Tat protein. The human CD26 gene is also located on the long arm of chromosome 2. CD26 is a lymphocyte cell surface antigen that is stimulated by interleukin-1 and serves with CD4 as a coreceptor that interacts with the V3 loop in gp120 of human immunodeficiency virus. The human immunodeficiency virus-induced interleukin-1 excess, thus, serves human immunodeficiency virus by enhancing replication, and by increasing human immunodeficiency virus infectivity via activation of CD26. IL-1 also adversely affects acquired immune deficiency syndrome-related Kaposi's sarcoma. Several genetic treatments for human immunodeficiency virus infection are proposed.

Glucocorticoids Induce Kaposi's Sarcoma Cell Proliferation Through the Regulation of Transforming Growth Factor-β

Glucocorticoid (GC) use is known to induce or enhance the growth of Kaposi's sarcoma (KS) in many clinical settings including human immunodeficiency virus infection, collagen vascular disease, lymphoproliferative disorders, and renal transplantation. Because GCs may induce immune suppression and thus tumor growth, we determined whether GCs had a direct effect on KS growth. We found that GCs directly induce the growth of KS cell lines. In examining the mechanism of action of GCs, we did not observe induction of known autocrine growth factors for KS including interleukin-1 (IL-1), IL-6, oncostatin-M, basic fibroblast growth factor (bFGF ), and vascular endothelial growth factor (VEGF ). We thus examined factor(s) that inhibit KS growth. Transforming growth factor-β (TGF-β) is produced by KS cells and has pleiotropic effects, including inhibiting the growth of hematopoietic and endothelial cells. We show that TGF-β is produced by KS cells in both the latent and active forms, and that TGF-β is an autocrine growth inhibitory factor. We then studied the effects of GCs on the regulation of TGF-β and found that GCs do not inhibit TGF-β transcription, but significantly inhibit TGF-β activation. This effect is mediated through regulation of the TGF-β activation pathway. TGF-β is activated by plasmin which is positively regulated by plasminogen activator (PA) and PA receptor (PAR), and negatively regulated by plasminogen activator inhibitor (PAI). GCs downregulated PAR and upregulated PAI. Thus, glucocorticoids enhance KS cell growth through the regulation of TGF-β activation.

Glucocorticoids Induce Kaposi's Sarcoma Cell Proliferation Through the Regulation of Transforming Growth Factor-β

Glucocorticoid (GC) use is known to induce or enhance the growth of Kaposi's sarcoma (KS) in many clinical settings including human immunodeficiency virus infection, collagen vascular disease, lymphoproliferative disorders, and renal transplantation. Because GCs may induce immune suppression and thus tumor growth, we determined whether GCs had a direct effect on KS growth. We found that GCs directly induce the growth of KS cell lines. In examining the mechanism of action of GCs, we did not observe induction of known autocrine growth factors for KS including interleukin-1 (IL-1), IL-6, oncostatin-M, basic fibroblast growth factor (bFGF ), and vascular endothelial growth factor (VEGF ). We thus examined factor(s) that inhibit KS growth. Transforming growth factor-β (TGF-β) is produced by KS cells and has pleiotropic effects, including inhibiting the growth of hematopoietic and endothelial cells. We show that TGF-β is produced by KS cells in both the latent and active forms, and that TGF-β is an autocrine growth inhibitory factor. We then studied the effects of GCs on the regulation of TGF-β and found that GCs do not inhibit TGF-β transcription, but significantly inhibit TGF-β activation. This effect is mediated through regulation of the TGF-β activation pathway. TGF-β is activated by plasmin which is positively regulated by plasminogen activator (PA) and PA receptor (PAR), and negatively regulated by plasminogen activator inhibitor (PAI). GCs downregulated PAR and upregulated PAI. Thus, glucocorticoids enhance KS cell growth through the regulation of TGF-β activation.

Vascular endothelial growth factor/vascular permeability factor is an autocrine growth factor for AIDS-Kaposi sarcoma

Kaposi sarcoma (KS) is the most common tumor associated with HIV-1 infection and develops in nearly 30% of cases. The principal features of this tumor are abnormal vascularization and the proliferation of endothelial cells and spindle (tumor) cells. KS-derived spindle cells induce vascular lesions and display enhanced vascular permeability when inoculated subcutaneously in the nude mouse. This finding suggests that angiogenesis and capillary permeability play a central role in the development and progression of KS. In this study, we show that AIDS-KS cell lines express higher levels of vascular endothelial growth factor/vascular permeability factor (VEGF/VGF) than either human umbilical vein endothelial cells or human aortic smooth muscle cells. AIDS-KS cells and primary tumor tissues also expressed high levels of Flt-1 and KDR, the receptors for VEGF, while the normal skin of the same patients did not show any expression. We further demonstrate that VEGF antisense oligonucleotides AS-1 and AS-3 specifically block VEGF mRNA and protein production and inhibit KS cell growth in a dose-dependent manner. Furthermore, growth of KS cells in nude mice was specifically inhibited by VEGF antisense oligonucleotides. These results show that VEGF is an autocrine growth factor for AIDS-KS cells. To our knowledge, this is the first report that shows that VEGF acts as a growth stimulator in a human tumor. Inhibitors of VEGF or its cognate receptors may thus be candidates for therapeutic intervention.

Advances in Kaposi's sarcoma

KS remains a challenge to clinicians and investigators more than a century after its initial description. Debate continues as to the cell of origin, as well as whether or not it is a true cancer. KS appears to be an opportunistic neoplasm, which in its earliest phase retains some features of a benign hyperproliferative process, but in its late stages behaves like an aggressive malignancy. Pathogenesis seems to involve a predisposed individual (genetically susceptible or immunologically compromised) who comes into contact with an infectious agent, most likely a virus. Cytokines appear to play a major role in the growth of the tumor. The exact role of the KSHV in this process will likely be the subject of much investigation in the future.

Human herpesvirus 8 encodes a homolog of interleukin-6

Kaposi's sarcoma is a multifocal lesion that is reported to be greatly influenced by cytokines such as interleukin-6 (IL-6) and oncostatin M. DNA sequences of a novel human gammaherpesvirus, termed human herpesvirus 8 (HHV-8) or Kaposi sarcoma-associated herpesvirus, have been identified in all epidemiological forms of Kaposi's sarcoma with high frequency. The presence of HHV-8 DNA is also clearly associated with certain B-cell lymphomas (body cavity-based lymphomas) and multicentric Castleman's disease. Sequence analysis of a 17-kb fragment revealed that adjacent to a block of conserved herpesvirus genes (major DNA-binding protein, glycoprotein B, and DNA polymerase), the genome of HHV-8 encodes structural homolog of IL-6. This cytokine is involved not only in the pathogenesis of Kaposi's sarcoma but also in certain B-cell lymphomas and multicentric Castleman's disease. The viral counterpart of IL-6 (vIL-6) has conserved important features such as cysteine residues involved in disulfide bridging or an amino-terminal signal peptide. Most notably, the region known to be involved in receptor binding is highly conserved in vIL-6. This conservation of essential features and the remarkable overlap between diseases associated with HHV-8 and diseases associated with IL-6 disregulation clearly suggest that vIL-6 is involved in HHV-8 pathogenesis.

The effects of preparations of human chorionic gonadotropin on AIDS-related Kaposi's sarcoma

BACKGROUND

Kaposi's sarcoma is the most common cancer in patients with the acquired immunodeficiency syndrome (AIDS). Recently, certain preparations of human chorionic gonadotropin (hCG) have been shown to inhibit the growth of Kaposi's sarcoma cell lines in vitro and in immunodeficient mice.

METHODS

After in vitro evaluation of four commercially available hCG preparations, the most active product was evaluated in 36 patients with AIDS-related Kaposi's sarcoma. In a phase 1-2 trial, 24 patients received intralesional injections of hCG three times a week for two weeks at doses of 250, 500, 1000, or 2000 IU (6 patients each). In each patient three nodular lesions were injected, two with the drug and one with diluent alone. In a double-blind trial, 12 additional patients were randomly assigned to receive intralesional injections of 2000 IU of hCG or diluent alone (6 patients each; two lesions per patient). At the conclusion of therapy, the lesions were measured, their gross appearance assessed, and biopsy specimens evaluated.

RESULTS

A.P.L. (Wyeth-Ayerst), which had the most in vitro activity against Kaposi's sarcoma cell lines, was selected for the clinical investigation. Treatment with A.P.L. was well tolerated at all doses. In the cohorts given 250, 500, 1000, and 2000 IU, 1, 5, 5, and 10 of the 12 injected lesions responded, respectively (P=0.03 for trend). Complete tumor regression was observed in one lesion each at the 250-IU and 500-IU doses, in two lesions given the 1000-IU dose, and in five lesions given the 2000-IU dose. In the double-blind study, none of the 12 lesions in the six patients injected with diluent had responses, as compared with 10 of the 12 lesions in the six patients injected with hCG (P=0.015). Microscopical evidence of apoptosis was observed only in hCG-treated lesions. The percentage of cells that died increased in a dose-dependent manner (P<0.001). Serum levels of follicle-stimulating hormone (P=0.002) and luteinizing hormone (P=0.001) declined after the last injection of hCG, but there was no effect on these hormones in the diluent-treated patients.

CONCLUSIONS

The intralesional injection of hCG induces the regression of AIDS-related Kaposi's sarcoma lesions in a dose-dependent manner. The response of these tumors appears to be mediated by the induction of apoptosis.

Low dose methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone with zalcitabine in patients with acquired immunodeficiency syndrome-related lymphoma. Effect on human immunodeficiency virus and serum interleukin-6 levels over time

BACKGROUND

Use of multiagent chemotherapy has been associated with complete remission (CR) in approximately 50% of patients with newly diagnosed acquired immunodeficiency syndrome (AIDS)-lymphoma, although additional AIDS-related complications may occur. Both chemotherapy and antiretroviral therapy were employed in an attempt to ascertain if the combination was safe, and associated with changes in human immunodeficiency virus (HIV) p24 antigen levels during the course of treatment.

METHODS

Low dose methotrexate, bleomycin, doxorubicin, cyclophosphamide, vincristine, and dexamethasone(M-BACOD) chemotherapy and zalcitabine (ddC) were employed in 28 patients. Since both vincristine and zalcitabine may cause peripheral neuropathy, a Phase I/II study design was employed. Serum was analyzed for immune complex dissociated (ICD) HIV p24 antigen and interleukin (IL)-6 levels during therapy.

RESULTS

CR was achieved in 14 of 25 patients (56%), with partial response (PR) in 5 (20%). CRs were equivalent in patients with good or poor prognostic indicators, including a history of AIDS prior to lymphoma (CR = 60%); and/or CD4 lymphocytes < 200/mm3 (CR = 53%). Five patients with a CR subsequently relapsed (36%); median survival of CR patients was 29.2 months (4.1-61+), whereas that of all of the treated patients was 8.1 months. No significant peripheral neuropathy or other toxicity was observed. Serum ICD p24 antigen levels either fell (7/14) or remained consistently negative (2/14) in 9 of 14 patients (64%), whereas 36% experienced an increase. Elevated serum IL-6 levels at diagnosis were associated with systemic "B" symptoms (P = 0.023), whereas changes in IL-6 correlated with response to therapy over time (P = 0.006).

CONCLUSIONS

Combination antineoplastic and zalcitabine antiretroviral therapy may be safely administered to patients with AIDS-related lymphoma, resulting in CR in 56%, lack of significant neurotoxicity, and favorable effect on HIV p24 antigen in 50%. Elevation of serum IL-6 is associated with systemic "B" symptoms, whereas changes in serum IL-6 may correlate with response.