Expressions of hepatic genes, especially IGF-binding protein-1, correlating with serum corticosterone in microarray analysis.

Microarray technology was evaluated for usefulness in assessing relationships between serum corticosterone and hepatic gene expression. Nine pairs of female Swiss mice were chosen to provide a wide range of serum corticosterone ratios; cDNA microarray analysis (approximately 8000 genes) was performed on their livers. A statistical method based on calculation of 99% confidence intervals discovered 32 genes which varied significantly among the livers. Five of these ratios correlated significantly with serum corticosterone ratio, including tyrosine aminotransferase, stress-induced protein, pleiotropic regulator 1 and insulin-like growth factor-binding protein-1; the latter has a potential role in cancer development. Secondly, linear regression of gene expression vs corticosterone ratios was screened for those with r> or =0.8 (P<0.01), yielding 141 genes, including some known to be corticosterone regulated and others of interest as possible glucocorticoid targets. Half of these significant correlations involved data sets where no microarray ratio exceeded +/- 1.5. These results showed that microarray may be used to survey tissues for changes in gene expression related to serum hormones, and that even small changes in expression can be of statistical significance in a study with adequate numbers of replicate samples.

Fibrinogen induces IL-8 synthesis in human neutrophils stimulated with formyl-methionyl-leucyl-phenylalanine or leukotriene B(4).

Human exudative neutrophils have greatly increased stores of the neutrophil chemoattractant IL-8 compared with peripheral blood cells, but the mechanism for the increase is not defined. In this report, we show that treatment of peripheral blood neutrophils with the chemotactic peptide fMLP or with leukotriene B(4) or fibrinogen results in little increase in the production of IL-8 by peripheral blood neutrophils. However, a chemotactically active dose of fMLP (5 x 10(-9) M) or leukotriene B(4) (1 x 10(-7) M) in the presence of a physiological concentration (2 mg/ml) of fibrinogen results in a receptor-mediated, pertussis toxin-sensitive, synergistic 30-fold increase in IL-8 synthesis. The levels of IL-8 attained are comparable to those observed in exudative cells. Higher concentrations of fMLP (1 x 10(-7) M) are associated with reduced IL-8 protein synthesis without IL-8 degradation, indicating a sensitive regulatory mechanism for IL-8 production. Treatment of neutrophils with fibrinogen and fMLP resulted in minimal changes in the steady state levels of mRNA for macrophage inflammatory protein-1alpha and -1beta and monocyte chemoattractant protein-1. In contrast, in the presence of fibrinogen, the steady-state level of neutrophil IL-8 mRNA increased 8-fold with 5 x 10(-9) M fMLP but was not decreased with 1 x 10(-7) M fMLP, suggesting that neutrophils are specifically adapted to modulate neutrophil IL-8 synthesis through transcriptional and posttranscriptional mechanisms. The data indicate that fibrinogen can function not only as a substrate in the clotting cascade, but also as an important effector during the evolution of the innate immune response.

Dual control of LIF expression and LIF receptor function regulate Stat3 activation at the onset of uterine receptivity and embryo implantation.

Leukemia inhibitory factor (LIF) expression in the uterus is essential for embryo implantation in mice. Here we describe the spatial and temporal regulation of LIF signaling in vivo by using tissues isolated from uteri on different days over the implantation period. During this time, LIF receptors are expressed predominantly in the luminal epithelium (LE) of the uterus. Isolated epithelium responds to LIF by phosphorylation and nuclear translocation of signal transducer and activator of transcription (Stat) 3, but not by an increase in mitogen-activated protein kinase levels. The related cytokines Il-6, ciliary neurotrophic factor, as well as epidermal growth factor, do not activate Stat3, although epidermal growth factor stimulates mitogen-activated protein kinase. In vivo Stat3 activation is induced by LIF alone, resulting in the localization of Stat3 specifically to the nuclei of the LE coinciding with the onset of uterine receptivity. The responsiveness of the LE to LIF is regulated temporally, with Stat activation being restricted to day 4 of pregnancy despite the presence of constant levels of LIF receptor throughout the preimplantation period. Uterine receptivity is therefore under dual control and is regulated by both the onset of LIF expression in the endometrial glands and the release from inhibition of receptor function in the LE.

A conformational C4 peptide polymer vaccine coupled with live recombinant vector priming is immunogenic but does not protect against rectal SIV challenge.

The conserved, immunogenic CD4 binding site on the viral envelope is an attractive HIV or SIV vaccine candidate. Polymerization of an 18 amino acid segment derived from the C4 domain of SIV gp120 produced a peptide polymer or "peptomer," having an alpha-helical conformation possibly mimicking a proposed structure of the C4 domain in the unbound native protein. The SIV peptomer and native gp120 were compared as subunit boosts following two adenovirus type 5 host range (Ad5hr)-SIVenv recombinant priming immunizations. Both vaccine regimens successfully elicited SIV-specific CTL responses in five of six immunized macaques. Peptomer-boosted macaques exhibited significantly higher envelope-specific T cell proliferative responses than either the gp120-boosted macaques or controls. Peptomer immunization also elicited peptomer and SIV gp120-specific binding antibodies, but only native gp120 boosting elicited SIV neutralizing antibodies. Upon intrarectal challenge with SIVmac32H, all nine macaques became infected. The solely envelope-based vaccine conferred no protection. However, changing the boosting immunogen to the C4 peptomer did not improve protective efficacy in spite of its elicitation of humoral and cellular immune responses, including robust T-helper activity. In spite of the peptomer's strong immunogenicity and potential for induction of broadly protective immune responses, it was not effective as a subunit vaccine.

The development of erectile dysfunction in men treated for prostate cancer.

PURPOSE: Erectile dysfunction is a common side effect in men treated for prostate cancer. Previously published studies document the incidence of erectile dysfunction in men treated for prostate cancer to be between 20% and 88%. To our knowledge a prospective evaluation focused on the development of erectile dysfunction in men treated for prostate cancer has not elucidated components of its chronology or risk factors. MATERIALS AND METHODS: A centralized prospective database of 2,956 patients diagnosed with prostate cancer at a single institution was studied in regard to pretreatment and posttreatment erectile dysfunction. Of these 2,956 patients 802 had sufficient information regarding erectile function and comprise our study population. Factors analyzed in regard to treatment and erectile dysfunction include treatment modality, that is radical prostatectomy, external beam radiation therapy and watchful waiting, and ethnicity, patient age, clinical stage and tumor histological grade. RESULTS: No significant difference was noted in the posttreatment erectile function between patients treated with radical prostatectomy or external beam radiation (10% versus 15%). Patients selecting watchful waiting had the lowest risk of erectile dysfunction. Clinical stage and race were significant predictors for the development of erectile dysfunction in the watchful waiting and external beam radiation treatment groups. CONCLUSIONS: Erectile dysfunction develops in greater than 80% of patients treated for prostate cancer. External beam radiation has the same risk for erectile dysfunction as radical prostatectomy.

Impact of HIV-1 infection and highly active antiretroviral therapy on the kinetics of CD4+ and CD8+ T cell turnover in HIV-infected patients.

To evaluate the effects of HIV infection on T cell turnover, we examined levels of DNA synthesis in lymph node and peripheral blood mononuclear cell subsets by using ex vivo labeling with BrdUrd. Compared with healthy controls (n = 67), HIV-infected patients (n = 57) had significant increases in the number and fraction of dividing CD4(+) and CD8(+) T cells. Higher percentages of dividing CD4(+) and CD8(+) T cells were noted in patients with the higher viral burdens. No direct correlation was noted between rates of T cell turnover and CD4(+) T cell counts. Marked reductions in CD4(+) and CD8(+) T cell proliferation were seen in 11/11 patients 1-12 weeks after initiation of highly active antiretroviral therapy (HAART). These reductions persisted for the length of the study (16-72 weeks). Decreases in naive T cell proliferation correlated with increases in the levels of T cell receptor rearrangement excision circles. Division of CD4(+) and CD8(+) T cells increased dramatically in association with rapid increases in HIV-1 viral loads in 9/9 patients 5 weeks after termination of HAART and declined to pre-HAART-termination levels 8 weeks after reinitiation of therapy. These data are consistent with the hypothesis that HIV-1 infection induces a viral burden-related, global activation of the immune system, leading to increases in lymphocyte proliferation.

Genetic and immunohistochemical analyses of p53 independently predict regional metastasis of gastric cancers.

Either p53 gene mutation or immunohistochemical detection of p53 protein has not been consistently shown to have prognostic significance in human cancers, including gastric carcinomas. One hypothesis to explain this inconsistency is that some p53 mutations and p53 protein accumulation are not indicative of tumor progression. To test this hypothesis, we categorized p53 status in 105 gastric carcinomas according to types of mutations, numerical scores of immunohistochemical staining (IHC), or combinations thereof. The p53 status was then correlated with metastasis to liver or peritoneum. Gastric cancers with no p53 mutations were significantly less likely to metastasize than tumors with mutations. Intermediate IHC scores were inversely associated with metastasis. A substantial number of gastric cancers (31 of 105) showed positive p53 immunostaining without detectable mutations (p53-/IHC+), which suggested an accumulation of wild-type p53 protein, and also a significantly lower risk for metastasis. After adjusting for depth of invasion and lymph node involvement, the p53-/IHC+ combination predicted low metastatic risk better than either p53- or IHC+ with intermediate scores. These findings suggest that an accumulation of wild-type p53 protein occurs in gastric cancer cells and represents a stress-response mechanism that lowers metastatic potential.

Elevations in serum soluble interleukin-2 receptor levels predict relapse in patients with hairy cell leukemia.

PURPOSE: Interferon-alfa, 2'-deoxycoformycin, and 2-chlorodeoxy-adenosine (2-CdA) are effective in the management of patients with hairy cell leukemia. These agents produce remissions in most patients, but relapses occur with all three drugs. The optimal means to follow patients for relapse after treatment has not been determined. METHODS: We retrospectively examined serial serum soluble interleukin-2 receptor levels (sIL-2R) and absolute granulocyte counts in eight patients with relapsed hairy cell leukemia. All were treated with 2-CdA at the time of relapse. Serum samples were available at 3- to 6-month intervals from 5 to 9 years before relapse and 2-CdA treatment RESULTS: sIL-2R levels increase only in patients who go on to relapse. sIL-2R levels doubled a mean of 17.1 months (range, 4-36 months) before absolute granulocyte count decreased by 50%. DISCUSSION: Demonstration of a rising serum sIL-2R level in patients with hairy cell leukemia identified those with an increased risk of relapse who need more frequent observation than patients who maintain a stable sIL-2R level. Early intervention may ameliorate the toxicity of salvage therapy because disease-related neutropenia may be anticipated.

Cross-protection in NYVAC-HIV-1-immunized/HIV-2-challenged but not in NYVAC-HIV-2-immunized/SHIV-challenged rhesus macaques.

OBJECTIVES: Immunization with attenuated poxvirus-HIV-1 recombinants followed by protein boosting had protected four of eight rhesus macaques from HIV-2SBL6669 challenge. The present study was designed to confirm this result and to conduct the reciprocal cross-protection experiment. METHODS: Twenty-four macaques were primed with NYVAC (a genetically attenuated Copenhagen vaccinia strain) recombinants with HIV-1 and HIV-2 env and gag-pol or NYVAC vector alone and boosted with homologous, oligomeric gp160 proteins or adjuvant only. Binding and neutralizing antibodies, cytotoxic T-lymphocytes (CTL) and CD8 T cell antiviral activity (CD8AA) were evaluated. One half of each immunization and control group were intravenously challenged with SHIV(HXB2) the other half was challenged with HIV-2SBL6669,. Protective outcome was assessed by monitoring virus isolation, proviral DNA and plasma viral RNA. RESULTS: Both immunization groups developed homologous binding antibodies; however, homologous neutralizing antibodies were only observed in NYVAC-HIV-2-immunized macaques. While no cross-reactive neutralizing antibodies were detected, both immunization groups displayed cross-reactive CTL. Significant CD8AA was observed for only one NYVAC-HIV-2-immunized macaque. Virological assessments verified that both NYVAC-HIV-1 and NYVAC-HIV-2 immunization significantly reduced viral burdens and partially protected against HIV-2 challenge, although cross-protection was not at the level that had been previously reported. Humoral antibody and/or CTL and CD8AA were associated with protection against homologous HIV-2 challenge, while cellular immune responses seemed more important for cross-protection. No significant protection was observed in the SHIV-challenged macaques, although NYVAC-HIV-1 immunization resulted in significantly lower viral burdens compared with controls. CONCLUSIONS: Further delineation of cross-reactive mechanisms may aid in the development of a broadly protective vaccine.

Treatment with tumor necrosis factor-alpha and granulocyte-macrophage colony-stimulating factor increases epidermal Langerhans' cell numbers in cancer patients.

Dendritic cells (DCs) initiate primary and stimulate secondary T-cell responses. We conducted a phase I trial of tumor necrosis factor (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF) in patients with cancer to increase DCs in peripheral blood or skin based on in vitro data that showed that CD34(+) hematopoietic precursors require these cytokines to mature into functional antigen-presenting DCs. Eleven patients were treated for 7 days with GM-CSF, 125 microg/m(2) twice daily as subcutaneous injections, and TNF-alpha as a continuous infusion at dose levels of 25, 50, or 100 microg/m(2)/day. The maximum tolerated dose of TNF-alpha was 50 microg/m(2)/day with this dose of GM-CSF; dose-limiting toxicities occurred in both patients treated with 100 microg/m(2)/day. One became thrombocytopenic and the other had transient confusion. Epidermal Langerhans' cells were quantitated by S100 staining of skin biopsies and DC precursors in peripheral blood by colony-forming unit dendritic (CFU-dendritic) assays. S100-positive cells in the epidermis doubled after treatment (2.55 S100(+) cells/high-power field before treatment to 6.05 after treatment, p = 0.029). CFU-dendritic in peripheral blood increased after treatment in 3 colorectal cancer patients but not in 3 patients with melanoma. CD11c(+) or CD123(+), HLA-DR(bright), lineage-negative dendritic cell precursors were not increased in peripheral blood mononuclear cells. This trial demonstrates that treatment with TNF-alpha and GM-CSF can increase the number of DCs in the skin and the number of dendritic cell precursors in the blood of some patients with cancer. This approach may increase the efficacy of vaccination to tumor antigens in cancer patients.

Alteration of Met protooncogene product expression and prognosis in breast carcinomas.

OBJECTIVE: To objectively quantify the expression and prognostic implications of the met protooncogene product (Met) in human breast cancer. STUDY DESIGN: One hundred eighty-two cases of primary human breast cancer were collected. Both the normal and tumor portions of the original surgical pathology specimen were immunostained for Met and imaged using laser scanning confocal microscopy. Then the cases were ranked according to relative concentrations of normal and tumor Met expression. Subsequently, they were quantified using image analysis and the results correlated with clinical outcome to determine the prognostic value of relative levels of Met. RESULTS: Using a quantitative index to evaluate the relative levels of Met expression, high levels of Met expression in the tumor as compared with the adjacent normal ducts predicted poor prognosis for overall survival and metastasis-free survival. The risk ratio for elevated Met expression was 3.94 (P = .0009). This new method also allows determination of the clinical relevance of low levels of Met in the tumor. The overall survival between the patient population with higher, lower and unchanged levels of Met in normal tissue as compared to tumor were significantly different (P = .0020). CONCLUSION: Our studies suggest that in a subpopulation of node-negative breast cancer patients, either high or low levels of Met in tumor tissue relative to normal tissue is an indicator of poor overall survival (P = .0068). Thus, Met expression could be useful for identifying node-negative patients who could benefit from adjuvant therapy.

Comparison of the Quantiplex version 3.0 assay and a sensitized Amplicor monitor assay for measurement of human immunodeficiency virus type 1 RNA levels in plasma samples.

This study evaluated correlation and agreement between version 3 of the Quantiplex human immunodeficiency virus type 1 (HIV-1) RNA assay (v3 branched DNA [bDNA]) and a sensitized Amplicor HIV-1 Monitor assay (reverse transcription [RT]-PCR) for the measurement of HIV RNA. Three hundred eighteen samples from 59 randomly selected, HIV-1-seropositive persons on various drug protocols from the National Institute of Allergy and Infectious Diseases HIV outpatient clinic were studied. The results indicate that v3 bDNA and RT-PCR are highly correlated (r = 0.98) and are in good agreement (mean difference in log(10) copies/ml +/- 2 standard deviations = 0.072 +/- 0.371). The relationship between values obtained by both assays is given by the following equation: log(10)v3 bDNA = -0.0915 + 1. 0052. log(10)RT-PCR. This represents a 1.026-fold difference between log(10)RT-PCR values and log(10)v3 bDNA values.

Nasal cytokine and chemokine responses in experimental influenza A virus infection: results of a placebo-controlled trial of intravenous zanamivir treatment.

The local immune response to influenza virus infection was characterized by determining cytokine and chemokine levels in serial nasal lavage fluid samples from 15 volunteers experimentally infected with influenza A/Texas/36/91 (H1N1). The study was part of a randomized double-blind placebo-controlled trial to determine the prophylactic effect of intravenous zanamivir (600 mg 2x/day for 5 days), a highly selective inhibitor of influenza A and B virus neuraminidases, on the clinical symptoms of influenza infection. Nasal lavage fluid levels of interleukin (IL)-6, tumor necrosis factor-alpha, interferon-gamma, IL-10, monocyte chemotactic protein-1, and macrophage inflammatory protein-1alpha and -1beta increased in response to influenza virus infection and correlated statistically with the magnitude and time course of the symptoms. Treatment with zanamivir prevented the infection and abrogated the local cytokine and chemokine responses. These results reveal a complex interplay of cytokines and chemokines in the development of symptoms and resolution of influenza.

Conditioned immune response to interferon-gamma in humans.

We determined whether a classical conditioning paradigm may be used to condition immunologic responses in normal human subjects receiving an optimal immunostimulating dose of recombinant human interferon-gamma (rhIFN-gamma). We conducted a placebo-controlled, double-blind study of 31 normal volunteers in order to determine whether an initially immune-neutral stimulus, oral propylene glycol (PG), could eventually elicit an immune response as a consequence of its being paired with a known immunostimulatory dose and schedule of rhIFN-gamma. Subjects were randomly assigned to one of three groups: (A) rhIFN-gamma injections paired with PG; (B) normal saline injections paired with PG; (C) rhIFN-gamma injections alone. During the 4-week study, subjects received progressively fewer injections so that, by the final week of the study, no injections were given and groups A and B received only PG. The principal outcome measures were serum concentrations of quinolinic acid (QUIN) and neopterin, two nonspecific but sensitive markers of immune activation, and expression of Fc receptors (CD64) on peripheral blood mononuclear cells. RhIFN-gamma injections produced significant and predictable alterations in each of the measured immune parameters. No group B subject made an immune response. Mean serum QUIN levels were significantly higher at the end of week three for subjects in the experimental condition (group A) than for subjects receiving rhIFN-gamma alone (group C) despite receiving identical doses of rhIFN-gamma. Similarly, the predicted decay in mean serum neopterin levels from the end of week 1 to the end of week 2 was seen in group C but not in group A. The exposure of group A to PG blunted the decline of CD64 expression in week four. The data suggest that the pairing of an unconditioned stimulus (rhIFN-gamma) and a conditioned stimulus (PG) permits the conditioned stimulus alone to prolong a cytokine-induced response in normal humans.

The ras oncogene-mediated sensitization of human cells to topoisomerase II inhibitor-induced apoptosis.

BACKGROUND: Among the inhibitors of the enzyme topoisomerase II (an important target for chemotherapeutic drugs) tested in the National Cancer Institute's In Vitro Antineoplastic Drug Screen, NSC 284682 (3'-hydroxydaunorubicin) and NSC 659687 [9-hydroxy-5,6-dimethyl-1-(N-[2(dimethylamino)ethyl]carbamoyl)-6H-pyrido -(4,3-b)carbazole] were the only compounds that were more cytotoxic to tumor cells harboring an activated ras oncogene than to tumor cells bearing wild-type ras alleles. Expression of the multidrug resistance proteins P-glycoprotein and MRP (multidrug resistance-associated protein) facilitates tumor cell resistance to topoisomerase II inhibitors. We investigated whether tumor cells with activated ras oncogenes showed enhanced sensitivity to other topoisomerase II inhibitors in the absence of the multidrug-resistant phenotype. METHODS: We studied 20 topoisomerase II inhibitors and individual cell lines with or without activated ras oncogenes and with varying degrees of multidrug resistance. RESULTS: In the absence of multidrug resistance, human tumor cell lines with activated ras oncogenes were uniformly more sensitive to most topoisomerase II inhibitors than were cell lines containing wild-type ras alleles. The compounds NSC 284682 and NSC 659687 were especially effective irrespective of the multidrug resistant phenotype. The ras oncogene-mediated sensitization to topoisomerase II inhibitors was far more prominent with the non-DNA-intercalating epipodophyllotoxins than with the DNA-intercalating inhibitors. This difference in sensitization appears to be related to a difference in apoptotic sensitivity, since the level of DNA damage generated by etoposide (an epipodophyllotoxin derivative) in immortalized human kidney epithelial cells expressing an activated ras oncogene was similar to that in the parental cells, but apoptosis was enhanced only in the former cells. CONCLUSIONS: Activated ras oncogenes appear to enhance the sensitivity of human tumor cells to topoisomerase II inhibitors by potentiating an apoptotic response. Epipodophyllotoxin-derived topoisomerase II inhibitors should be more effective than the DNA-intercalating inhibitors against tumor cells with activated ras oncogenes.

Ras oncogene-induced sensitization to 1-beta-D-arabinofuranosylcytosine.

Human tumor cells containing ras oncogenes display enhanced sensitivity to 1-beta-D-arabinofuranosylcytosine (Ara-C) and other deoxycytidine analogues (H-M. Koo, et al., Cancer Res., 56: 5211-5216, 1996). Human tumor cell lines with or without a ras oncogene as well as a pair of isogenic cell lines with one containing an activated ras oncogene were used to study the basis for differential sensitivity. We found that human tumor cells containing ras oncogenes upon entry into the S phase of the cell cycle underwent apoptosis in response to Ara-C treatment. By contrast, human tumor cells harboring wild-type ras alleles were only delayed in the S phase when exposed to Ara-C. Thus, the ras oncogene specifically renders human cells more sensitive to Ara-C by preventing S-phase arrest. This may occur by the ras oncogene compromising an S-phase checkpoint.

Phase I trial of anti-CD3-stimulated CD4+ T cells, infusional interleukin-2, and cyclophosphamide in patients with advanced cancer.

PURPOSE: We performed a phase I trial to determine whether in vivo expansion of activated CD4+ T cells was possible in cancer patients. 111Indium labeling was used to observe trafficking patterns of the infused stimulated CD4+ T cells. The influence of cyclophosphamide (CTX) dosing on immunologic outcome was also examined. PATIENTS AND METHODS: Patients with advanced solid tumors or non-Hodgkin's lymphoma received CTX at 300 or 1,000 mg/m2 intravenously (i.v.). Leukapheresis was performed to harvest peripheral-blood mononuclear cells (PBMCs) either just before the CTX dose, or when the patient was either entering or recovering from the leukocyte nadir induced by CTX. An enriched population of CD4+ T cells was obtained by negative selection. The CD4+ T cells were activated ex vivo with anti-CD3, cultured with interleukin-2 (IL-2) for 4 days, and adoptively transferred. After adoptive transfer, patients received IL-2 (9.0 x 10(6) IU/m2/d) by continuous infusion for 7 days. RESULTS: The absolute number of CD4+, CD4+/DR+, and CD4+/CD45RO+ T cells increased in a statistically significant fashion in all cohorts after the first course of therapy. The degree of CD4 expansion was much greater than CD8 expansion, which resulted in a CD4:CD8 ratio that increased in 26 of 31 patients. The greatest in vivo CD4 expansion occurred when cells were harvested as patients entered the CTX-induced nadir. One complete response (CR), two partial responses (PRs), and eight minor responses were observed. Trafficking of 111Indium-labeled CD4 cells to subcutaneous melanoma deposits was also documented. CONCLUSION: CD4+ T cells can be expanded in vivo in cancer patients, which results in increased CD4:CD8 ratios. The timing of pheresis in relation to CTX administration influences the degree of CD4 expansion. Tumor responses with this regimen were observed in a variety of tumors, including melanoma and non-Hodgkin's lymphoma; a high percentage of patients had at least some tumor regression from the regimen that produced the greatest CD4+ T-cell expansion.

A phase II study of carboplatin, cisplatin, interferon-alpha, and tamoxifen for patients with metastatic melanoma.

The purpose of this trial was to determine the toxicity and antineoplastic activity of cisplatin, carboplatin, tamoxifen, and interferon-alpha (IFN-alpha) in patients with advanced melanoma. Eleven patients with metastatic melanoma were enrolled. The patients received carboplatin 400 mg/m2 i.v. on day 0; cisplatin 25 mg/m2 i.v. on days 7, 14, and 21; tamoxifen 20 mg p.o. b.i.d. on days 0-27; and interferon-alpha 5 million units/m2 subcutaneously 3 times per week. Cycles were repeated every 28 days. Patients were assessed for tumor response at the end of 2 cycles. Toxicity was severe, with 14 of 24 cycles given requiring some form of dose reduction. Carboplatin dose reductions were related to bone-marrow toxicity, whereas IFN-alpha caused fatigue, arthralgias, myalgias, and fever. The overall response rate was 18% (2 partial responses [PRs]). The combination of cisplatin, carboplatin, tamoxifen, and IFN-alpha is active in advanced melanoma; however, the toxicity is unacceptable.

Inhibition of Friend virus replication by a compound that reacts with the nucleocapsid zinc finger: anti-retroviral effect demonstrated in vivo.

The zinc finger structure that is found in the nucleocapsid protein of nearly all retroviruses has been proposed as a target for antiviral therapy. Since compounds that chemically attack the cysteines of the finger have been shown to inactivate both human immunodeficiency virus type 1 (HIV-1) and murine leukemia virus (MuLV) in vitro, 14 of these compounds were tested in an MuLV-induced Friend disease model to assess their ability to inhibit retroviral replication in vivo. Of the 14 compounds tested, only Aldrithiol-2 clearly exhibited anti-retroviral activity as measured indirectly by the delay of Friend disease onset (P < 0.05). These results were confirmed by quantitative competitive polymerase chain reaction studies which monitored viral spread by measuring the level of viral DNA in the peripheral blood mononuclear cells of treated mice. Comparison of treated mice with untreated mice revealed that Aldrithiol-2 produced a greater than 2-log reduction in virus levels. These results functionally demonstrate that a zinc finger-attacking compound can inhibit viral replication in vivo. Since only 1 of the 14 compounds studied was effective, this study also shows the importance of in vivo testing of these types of antiviral compounds in an animal model. Given the strict conservation of the metal-coordinating cysteine structure within HIV-1 and MuLV zinc fingers, our results support the proposal that anti-retroviral drugs which target the nucleocapsid zinc finger may be clinically useful against HIV-1.

T cell- and NK cell-independent inhibition of hepatic metastases by systemic administration of an IL-12-expressing recombinant adenovirus.

IL-12 is a potent immunoregulatory cytokine that has been shown to mediate tumor regression in a variety of tumor models. We describe the construction of AdCMV-IL-12, a recombinant adenovirus that encodes both subunits of IL-12 under transcriptional control of the CMV promoter. This recombinant virus efficiently infects a wide variety of cell types leading to the production of high levels of biologically active IL-12. Because the liver is a primary site of infection after i.v.-administered adenovirus, we tested the therapeutic efficacy of this virus in a murine hepatic metastasis tumor model. Systemic administration of AdCMV-IL-12 dramatically inhibited the formation of 3-day Renca hepatic metastases (mean of 16 metastases per liver) compared with the control virus AdCMV-betagal (mean of 209) or vehicle alone (mean of 272). Histologic analysis indicated that metastatic growth inhibition was accompanied by a dramatic perivascular infiltrate consisting of T cells, macrophages, and neutrophils. Therapeutic efficacy was not diminished in animals depleted of CD4+ or CD8+ T cells, or in SCID mice, even after NK cell ablation. In the latter case, a hepatic perivascular infiltrate composed of macrophages and neutrophils was observed after AdCMV-IL-12-treatment, while numerous activated Kupffer cells were noted in the hepatic parenchyma. Analysis of therapy-induced changes in hepatic gene expression demonstrated increased levels of IP-10 and Mig RNAs, but no increase in iNOS, Fas, or FasL RNA levels was observed. Our data suggest a model of metastatic growth inhibition mediated by nonlymphocyte effector cells including macrophages and neutrophils and that may involve anti-angiogenic chemokines.