Tumor regressions observed in patients with metastatic melanoma treated with an antigenic peptide encoded by gene MAGE-3 and presented by HLA-A1

Thirty-nine tumor-bearing patients with metastatic melanoma were treated with 3 subcutaneous injections of the MAGE-3.A1 peptide at monthly intervals. No significant toxicity was observed. Of the 25 patients who received the complete treatment, 7 displayed significant tumor regressions. All but one of these regressions involved cutaneous metastases. Three regressions were complete and 2 of these led to a disease-free state, which persisted for more than 2 years after the beginning of treatment. No evidence for a cytolytic T lymphocyte (CTL) response was found in the blood of the 4 patients who were analyzed, including 2 who displayed complete tumor regression. Our results suggest that injection of the MAGE-3.A1 peptide induced tumor regression in a significant number of the patients, even though no massive CTL response was produced.

Molecular basis for the relationship between thrombosis and cancer

Cancer patients are highly susceptible to thromboembolic complications, which some have estimated accounts for a significant percentage of the morbidity and mortality of the disease. Not all of the mechanisms for the production of the hypercoagulable state characteristic of cancer are entirely understood. Those that are known seem to interdigitate the biology of cancer with the major regulatory pathways that mediate blood coagulation, platelet-vessel wall interaction, fibrinolysis and inflammatory cytokine production. In other words, the events responsible for thrombosis in cancer appears to be a result of an over exuberant host response in an attempt to delimit tumor growth. In this brief review, therefore, we attempt to put into the context of tumor growth, angiogenesis and metastasis the current information about the pathogenesis of venous thromboembolism (VTE).

Persistent clinical response to the anti-TNF-alpha antibody infliximab in patients with ankylosing spondylitis over 3 years

OBJECTIVE

Infliximab, a monoclonal antibody against tumour necrosis factor alpha (TNF-alpha), is approved in Europe for the treatment of patients with active ankylosing spondylitis (AS) who have responded inadequately to conventional therapy. This report provides analyses from a 3-yr extension study, as a follow-up to both the 1- and 2-yr open label extensions of the original 3-month randomized controlled trial of infliximab in patients with AS.

METHODS

Of the 49 patients with AS who completed the second year of the study, 46 continued treatment with infliximab 5 mg/kg every 6 weeks up to week 156. The Bath AS Disease Activity Index (BASDAI), the Bath AS Functional Index, the Bath AS Metrology Index, patient's and physician's global assessments, quality of life (Short Form-36), C-reactive protein (CRP) and erythrocyte sedimentation rate were assessed throughout the study period.

RESULTS

The improvement of signs and symptoms observed in the majority of the patients during the first and second year was sustained throughout the third year of the study. Forty-three patients (62% of the 69 patients enrolled at baseline and 93% of the patients who started the third year) completed week 156. In the intention-to-treat analysis, an ASAS '5 out of 6' and ASAS 40% response was seen by 46% and 50% of the patients, respectively. The scores for other efficacy assessments were similar to the values observed at weeks 54 and 102. Median CRP levels remained low (1.5 mg/l at week 156). There were no relevant side-effects and no discontinuation because of drug-related adverse events during the third year of the study.

CONCLUSIONS

Patients with AS receiving infliximab for 3 yr showed a durable clinical response without loss of efficacy. Long-term infliximab treatment was well tolerated by patients in this study.

Recent advances of highly selective CDK4/6 inhibitors in breast cancer

Uncontrolled cell division is the hallmark of cancers. Full understanding of cell cycle regulation would contribute to promising cancer therapies. In particular, cyclin-dependent kinases 4/6 (CDK4/6), which are pivotal drivers of cell proliferation by combination with cyclin D, draw more and more attention. Subsequently, extensive studies were carried out to explore drugs inhibiting CDK4/6 and assess the efficacy and safety of these drugs in cancer, especially breast cancer. Due to the insuperable adverse events and the less activity observed in vivo, the drug development of the initial pan-CDK inhibitor flavopiridol was consequently discontinued, and then highly specific inhibitors were extensively researched and developed, including palbociclib (PD0332991), ribociclib (LEE011), and abemaciclib (LY2835219). Food and Drug Administration has approved palbociclib and ribociclib for the treatment of hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced or metastatic breast cancer, and recent clinical trial data suggest that palbociclib significantly improved clinical outcome when combined with letrozole or fulvestrant. Besides, the favorable effects of abemaciclib on prolonging survival of breast cancer patients have also been observed in clinical trials both for single-agent and combination strategy. In this review, we outline the preclinical and clinical advancement of these three orally bioavailable and highly selective CDK4/6 inhibitors in breast cancer.

Phase 1/2 study of subcutaneous and intradermal immunization with a recombinant MAGE-3 protein in patients with detectable metastatic melanoma

The purpose of this phase 1/2 study was to evaluate toxicity, tumor evolution and immunologic response following administration of a fixed dose of a recombinant MAGE-3 protein by subcutaneous and intradermal routes in the absence of immunologic adjuvant. Thirty-two patients with detectable metastatic melanoma expressing gene MAGE-3 were included and 30 received at least one injection with a fixed dose of a ProtD-MAGE-3 fusion protein. The immunization schedule included 6 intradermal and subcutaneous injections at 3-week intervals. Afterward, patients without major tumor progression who required other treatments received additional vaccinations at increasing time intervals. The vaccine was generally well tolerated. Among the 26 patients who received at least 4 vaccinations, we observed 1 partial response and 4 mixed responses. For these 5 responding patients, time to progression varied from 3.5 to 51+ months. An anti-MAGE-3 CD4 T-lymphocyte response was detected in 1 out of the 5 responding patients. The majority of patients had no anti-MAGE-3 antibody response. The clinical and immunologic responses generated by the vaccine are rather limited. Nevertheless, given the potential antitumor efficacy and the very mild toxicity of vaccinations, further studies combining MAGE proteins and/or peptides with potent immunologic adjuvants are warranted, not only in metastatic melanoma, but also in the adjuvant setting.

Phase I trial of intravenous peptide-pulsed dendritic cells in patients with metastatic melanoma

Sixteen patients with metastatic stage IV melanoma were treated with use of intravenous infusions of dendritic cells (DC) derived by incubation of plastic-adherent peripheral blood mononuclear cells (PBMC) with IL-4 and GM-CSF for 8 days in serumless AIM-V medium, followed by overnight pulsing with peptides. The tyrosinase368-376 (370D) and gp100(209-217 (210M)) peptides restricted to HLA class I A*0201 each differed from wild type by one amino acid modified to increase HLA binding. Median age was 49, with nine men and seven women. All patients, except one, had visceral disease. Patients received escalating doses of peptide-pulsed DCs at 10e7, 3 x 10e7, and 10e8 cells/dose twice at 2 weeks apart, with toxicity and clinical and immune responses as the principal endpoints. The first infusion of DCs was fresh, and frozen DCs were given for the second infusion of each cycle. Mean DC purity by flow cytometry was 49%, with a mean HLA-DR level of 57%, CD86 of 41%, CD58 of 46%, and mean CD14 cells of 0.9%. Toxicity was minimal, with two patients having transient grade III DC-related toxicity. Ten patients received one cycle of treatment and six patients received two cycles of treatment. One patient had a complete remission (CR) of lung and pleural disease after two cycles of DC therapy. Two additional patients had stable disease and two patients had mixed responses. Overall immunity was assessed by recall skin testing with peptides, gamma interferon ELISA assays of peptide specific cytolytic T cell (CTL) stimulated twice with peptide, IL-2, and IL-7 over 24 days, and peptide-specific tetramer assays performed before and after vaccination. Five of 16 patients had an immune response to gp100 or tyrosinase by gamma interferon ELISA assay; four of five were clinically stable or had tumor regression. These data suggest that melanoma antigen peptide-pulsed DC given intravenously are not toxic, and regression or stability of tumor appeared to correlate with the detection of a peptide-specific immune response in the peripheral blood.

Epidermal growth factor receptor signaling and the invasive phenotype of ovarian carcinoma cells

BACKGROUND

Most (70%-100%) ovarian carcinomas express high levels of the epidermal growth factor receptor (EGFR). To examine the relationship between EGFR and the invasive phenotype, we assessed integrin expression, adhesion, matrix metalloproteinase (MMP) activity, and migration in ovarian cancer cells in which EGFR expression was modified.

METHODS

NIH:OVCAR-8 human ovarian carcinoma cells were transfected with an expression vector containing the human EGFR complementary DNA in an antisense orientation (EGFR-antisense cells) or the vector alone (vector control cells). We compared vector control and EGFR-antisense cells for cell morphology and adhesion by light microscopy, expression of alpha(6)- and alpha(3)-integrin subunits by flow cytometry, MMP and tissue inhibitor of MMP (TIMP) activity by zymography, and migration by a wound migration assay. In some experiments, EGFR kinase activity in parental cells was inhibited by treatment with PD153035. All statistical tests were two-sided.

RESULTS

EGFR-antisense cells were morphologically distinct from vector control cells and had a selective decrease in adhesion to laminin-1 that was not observed with vector control cells (P = .008) or on other extracellular matrix substrates. Compared with vector control cells, cell surface alpha(6)-integrin expression decreased by approximately 80% (difference = 78.7%; 95% confidence interval [CI] = 77.8% to 79.6), MMP-9 activity decreased by approximately 50%, and TIMP activity increased by approximately 50% in EGFR-antisense cells. Vector control cells were highly motile (5.51 arbitrary distance unit; 95% CI = 4.98 to 6.04), whereas the EGFR-antisense cells were not (0.99 arbitrary distance units; 95% CI = 0.38 to 1.60). The morphology and integrin profile of NIH:OVCAR-8 parental cells treated with PD153035 were similar to those of the EGFR-antisense cells.

CONCLUSIONS

Reduced EGFR expression in ovarian carcinoma cells decreased their adhesion to laminin-1, expression of the alpha(6)-integrin subunit (a well-characterized laminin-1 receptor), and MMP-9 activity. These data support the hypothesis that EGFR overexpression in ovarian cancer cells results in multiple phenotypic changes that enhance the invasive phenotype.

Tumor-derived TGF-beta reduces the efficacy of dendritic cell/tumor fusion vaccine

Dendritic cell (DC)-based antitumor vaccine is a novel cancer immunotherapy that is promising for reducing cancer-related mortality. However, results from early clinical trials were suboptimal. A possible explanation is that many tumors secrete immunosuppressive factors such as TGF-beta, which may hamper host immune response to DC vaccine. In this study, we demonstrated that TGF-beta produced by tumors significantly reduced the potency of DC/tumor fusion vaccines. TGF-beta-secreting (CT26-TGF-beta) stable mouse colon cancer cell lines were generated using a retroviral vector expressing TGF-beta. A non-TGF-beta-secreting (CT26-neo) cell line was generated using an empty retroviral vector. The efficacies of DC/tumor fusion vaccines were assessed in vitro and in vivo. DC/CT26-TGF-beta fusion cells failed to induce a strong T cell proliferative response in vitro, mainly due to the effect of TGF-beta on T cell responsiveness rather than DC stimulatory capability. Animals vaccinated with DC/CT26-TGF-beta fusion vaccine had lower tumor-specific CTL activity and had significantly lower survival after tumor challenge as compared with animals immunized with DC/CT26-neo hybrids (45 vs 77%, p < 0.05). Ex vivo exposure of DCs to TGF-beta did not appear to lessen the efficacy of DC vaccine. These data suggest that tumor-derived TGF-beta reduces the efficacy of DC/tumor fusion vaccine via an in vivo mechanism. Neutralization of TGF-beta produced by the fusion cells may enhance the effectiveness of DC-based immunotherapy.

A phase I trial of an HLA-A1 restricted MAGE-3 epitope peptide with incomplete Freund's adjuvant in patients with resected high-risk melanoma

Cytolytic and helper T cells recognize small peptide fragments of protein antigens that are intracellularly processed and delivered to the cell surface in conjunction with HLA molecules. In mice, peptide vaccines can protect against lethal virus infections and tumor challenges. To test whether epitope peptides derived from a human tumor antigen can induce immune responses in patients, a vaccine was prepared consisting of an HLA-A1-restricted epitope of the antigen MAGE-3 mixed with a pan-class II epitope peptide PADRE and emulsified with incomplete Freund's adjuvant. Eighteen patients with resected stages III and IV melanoma at high risk for relapse were vaccinated subcutaneously with increasing doses of the MAGE-3 vaccine ranging from 100 to 2,000 micrograms per injection four times, each 4 weeks apart. The purpose of the phase I trial was to assess the toxicity, tolerability, and immune responses to the vaccine. The vaccine was not toxic, with only one case of grade III lethargy, and most patients complaining of grade I or II local pain, swelling, and tenderness at the injection sites. Peripheral blood mononuclear cells (PBMC) were collected from most patients prior to and after vaccination and used for assessment of global levels of immunity prevaccination, and to measure immune responses to the MAGE-3 and PADRE peptides prior to and after vaccination. Significant defects in global immunity shown by anergy to DTH skin testing in 7 of 16 patients and decreased proliferation to PHA (phytohemagglutinin) and CASTA, a Candida albicans protein extract, were observed. Seven of nine patients showed an increased response to PADRE after restimulation in vitro. Five of 14 patients at doses from 100 to 2,000 micrograms demonstrated an immune response to MAGE-3 by cytolysis of MAGE-3-specific target cells. Release of gamma interferon by T cells from 8 patients at the 100, 1,000, or 2,000 micrograms dose was measured after vaccination, and only two of eight patients showed an increase indicating augmented antigen-specific immunity. These data suggest that immune responses can be detected against PADRE and MAGE-3 in vaccinated melanoma patients, albeit with a low frequency of effector cells.

Adjuvant immunization of HLA-A2-positive melanoma patients with a modified gp100 peptide induces peptide-specific CD8+ T-cell responses

PURPOSE

To measure the CD8+ T-cell response to a melanoma peptide vaccine and to compare an every-2-weeks with an every-3-weeks vaccination schedule.

PATIENTS AND METHODS

Thirty HLA-A2-positive patients with resected stage I to III melanoma were randomly assigned to receive vaccinations every 2 weeks (13 vaccines) or every 3 weeks (nine vaccines) for 6 months. The synthetic, modified gp100 peptide, g209-2M, and a control peptide, HPV16 E7, were mixed in incomplete Freund's adjuvant and injected subcutaneously. Peripheral blood mononuclear cells obtained before and after vaccination by leukapheresis were analyzed using a fluorescence-based HLA/peptide-tetramer binding assay and cytokine flow cytometry.

RESULTS

Vaccination induced an increase in peptide-specific T cells in 28 of 29 patients. The median frequency of CD8+ T cells specific for the g209-2M peptide increased markedly from 0.02% before to 0.34% after vaccination (P <.0001). Eight patients (28%) exhibited peptide-specific CD8+ T-cell frequencies greater than 1%, including two patients with frequencies of 4.96% and 8.86%, respectively. Interferon alfa-2b-treated patients also had significant increases in tetramer-binding cells (P <.0001). No difference was observed between the every-2-weeks and the every-3-weeks vaccination schedules (P =.59).

CONCLUSION

Flow cytometric analysis of HLA/peptide-tetramer binding cells was a reliable means of quantifying the CD8+ T-cell response to peptide immunization. This assay may be suitable for use in future trials to optimize different vaccination strategies. Concurrent interferon treatment did not inhibit the development of a peptide-specific immune response and vaccination every 2 weeks, and every 3 weeks produced similar results.

Hypopigmentation associated with an adenovirus-mediated gp100/MART-1-transduced dendritic cell vaccine for metastatic melanoma

BACKGROUND

Reports of vitiligo associated with metastases and rare cases of spontaneous regression of disease have fueled enthusiasm for immunologic approaches to the treatment of advanced melanoma. More recent strategies have focused on using antigen-presenting dendritic cells as vaccines.

OBSERVATIONS

We observed 3 cases of leukoderma associated with a novel adenovirus-mediated gp100/MART-1-transduced dendritic cell (MART indicates melanoma antigen recognized by T cells). All 3 patients had advanced metastatic melanoma. Despite the development of this leukodermic response, all patients experienced disease progression while under treatment.

CONCLUSION

We provide the initial evidence for effective induction of a leukodermic response with a gp100/MART-1-transduced dendritic cell vaccine.

Paraneoplastic ophthalmoplegia and subacute motor axonal neuropathy associated with anti-GQ1b antibodies in a patient with malignant melanoma

A 68 year old woman developed oculomotor paresis shortly after metastatic progression of her melanoma was discovered. She was then immunised with the tumour antigen MAGE-3 in combination with an immunological adjuvant. During immunisation her symptoms worsened and she developed severe, predominantly proximal axonal motor neuropathy and became bedridden. IgM antibodies against gangliosides GM2, GD3, and GQ1b were detected in serum obtained two weeks before and nine weeks after the onset of symptoms. Immunohistochemically, the patient's IgM reacted with the tumour and co-localised with GQ1b. She improved neurologically following steroid treatment and became ambulatory.

Allogeneic human liposomal melanoma vaccine with or without IL-2 in metastatic melanoma patients: clinical and immunobiological effects

The aim of this pilot study was to assess the clinical and immunological effects of human allogeneic liposomal melanoma vaccine alone or combined with Interleukin-2 (IL-2) in patients with metastatic melanoma. Four concurrent treatment arms were included: vaccine alone (A); vaccine combined with systemic IL-2 (B); vaccine combined with low-dose liposomal regional IL-2 (C); and low-dose regional IL-2 as in group C but without vaccine (D). Vaccine was prepared from semisynthetic phospholipids (dimyristol phosphatidylcholine and dimyristol phosphatidylglycerol) and membranes of six human melanoma cell lines. The latter were chosen as expressing MHC class I and II antigens and a "mosaic" of melanoma-associated antigens (MAAs) as detected by MoAbs R24, p97, CF21 and TA99. Nine of the 24 patients had objective clinical responses: of the ten patients treated with liposomal vaccine and low dose regional IL-2 (arm C), three had complete responses (CR) and three had partial responses (PR); of the five patients treated with liposomal, low-dose regional liposomal IL-2 only (arm D), three had PRs. No clinical responses were seen in patients treated by vaccine alone (A) nor in patients treated by vaccine and systemic IL-2 (B). Patients' in vivo and in vitro cellular immune responses were closely monitored. Conversion to positive cutaneous delayed type hypersensitivity (DTH) to membrane vaccine (without liposomes) was induced only in the six clinical responders of arm C. Positive DTH correlated with augmented in vitro proliferative lymphocyte responses stimulated by melanoma cell lines and membrane preparation and with the augmented cytolytic activity against melanoma cell lines.

[TNF blockade in rheumatoid arthritis can cause severe fibrosing alveolitis. Six case reports]

TNF-blockade has been increasingly used in the treatment of rheumatoid arthritis (RA). However, the safety is unclear and an increased risk of both tuberculosis and other infections has been identified. Recently severe fibrosing alveolitis has also been reported in RA-patients treated with TNF-blockade. We report a further six RA patients, who during treatment with infliximab or etanercept developed fulminant lung fibrosis with alveolitis. For four of the patients, the fibrosing alveolitis was fatal. All patients were RF positive and above 60 years and five had mild fibrosis associated with RA before TNF-blockade treatment. Duration of TNF-blockade treatment was for three patients only two months and for the other three, 20-51 months. Age above 60 years and previous lung fibrosis appear to be risk factors for developing fibrosing alveolitis in RA patients treated with TNF-blockade.

Phase I trial of a melanoma vaccine with gp100(280-288) peptide and tetanus helper peptide in adjuvant: immunologic and clinical outcomes

A melanoma vaccine composed of HLA-A2-restricted peptide YLEPGPVTA (gp100(280)), with or without a modified T-helper epitope from tetanus toxoid AQYIKANSKFIGITEL, has been evaluated in a Phase I trial to assess safety and immunological response. The vaccines were administered s.c. in either of two adjuvants, Montanide ISA-51 or QS-21, to 22 patients with high-risk resected melanoma (stage IIB-IV). Local and systemic toxicities were mild and transient. We detected CTL responses to the gp100(280) peptide in peripheral blood in 14% of patients. Helper T-cell responses to the tetanus helper peptide were detected in 79% of patients and had a Th1 cytokine profile. One patient with a CTL response to gp100 had a recurrence in a lymph node 2 years later; her nodes contained CD8+ cells reactive to gp100(280) (0.24%), which proliferated in response to peptide. The overall survival of patients is 75% (95% confidence interval, 57-94%) at 4.7 years follow-up, which compares favorably with expected survival. Four of 14 patients who completed at least six vaccines subsequently developed metastases, all of which were solitary and surgically resectable. They remain alive and clinically free of disease at last follow-up. Data from this trial demonstrate immunogenicity of the gp100(280) peptide and suggest that immune responses may persist long-term in some patients. The frequency and magnitude of the CTL response may be improved with more aggressive vaccination regimens. Although this Phase I study was not intended to evaluate clinical benefit, the excellent survival of patients on this protocol suggests the possibility of a benefit that should be assessed in future studies.

Human tumor gangliosides inhibit murine immune responses in vivo

Gangliosides which are shed by tumor cells clearly inhibit cellular immune responses in vitro. However, the immunosuppressive activity of these molecules have been more difficult to ascertain in vivo. Here we have adapted a murine model to determine the effects of tumor gangliosides in an in vivo microenvironment, the lymph node draining the site of stimulation by allogeneic cells. In this model, allogeneic splenocytes (BALB/c) are s.c. injected into C3H mice. The cellular immune response in the draining popliteal lymph nodes 4 days later is evidenced as an increase in lymph node mass (2-fold), lymphocyte number (6-fold), and lymphocyte DNA synthesis (6-fold). Purified human neuroblastoma gangliosides (10 nmol) coinjected with the stimulating allogeneic cells significantly suppressed this in vivo immune response. The increase in the lymph node mass was reduced by 65% (0.66 versus 1.89 mg), the increase in lymphocyte number (4.0 x 10(6) cells/node) was almost completely inhibited (1.1 x 10(6) cells/node), and in vitro [3H]thymidine uptake by the lymphocytes recovered in vivo was reduced by 80%. In contrast to the inhibition by tumor gangliosides, liposomes of cholesterol:lecithin were not inhibitory. Thus, tumor gangliosides, specifically, modulate cellular immune responses in vivo, which may contribute to the observed enhancement of tumor formation by these molecules.

[Increased risk of infection with biological immunomodifying antirheumatic agents. Clear guidelines are necessary as shown by case reports]

Several potent immunosuppressive drugs have become available in the new millennium for patients with rheumatologic diseases, Crohn's disease and other autoimmune disorders. Five patient cases from Växjö central hospital (uptake area 178 000 individuals) with Listeria meningitis, Pneumocystis jiroveci and tuberculosis pneumonia, Listeria sepsis, Legionella pneumonia and E coli sepsis are described. A doubled risk for infections has previously been observed for RA patients, as compared to healthy individuals. There is clearly an increased risk of tuberculosis (depending on the actual and historic environmental prevalence) for patients on TNF antagonists, and therefore tuberculosis screening is now mandatory before start of therapy. Since TNF has a central role in the immune defence, an increased risk of opportunistic infections like listeriosis. mycobacteriosis, and invasive fungal infections has been established. Eight hospitals in southern Sweden participate in a register for the use of TNF blockers in rheumatologic diseases (South Swedish Arthritis Treatment Group, SSATG). Guidelines for screening and treatment of latent and active tuberculosis, possible prophylactic antibiotic treatment for endocarditis and vaccination programs for patients on TNF antagonists are discussed.

[Clinical experience with TNF-alpha inhibitors in rheumatoid arthritis]

BACKGROUND

Infliximab and etanercept, both tumour necrosis factor-alpha inhibitors, are proven to be effective in patients with rheumatoid arthritis in randomised controlled trials.

MATERIAL AND METHODS

Patients with active rheumatoid arthritis were treated with infliximab (n = 29) or etanercept (n = 24) in clinical hospital practice. They were examined before and during treatment. All patients had tried at least one DMARD before. Details of disease activity were monitored by measuring tender and swollen joints, global and pain patient visual analogue scales, Disease Activity Index Score (DAS 28), the Modified Health Assessment Questionnaire, blood and urine samples, and adverse effects. The patients were monitored regularly for two years or until they stopped treatment.

RESULTS

In the infliximab group we observed statistically significantly better values for all the registered variables after 6 weeks. At the other times of registration the variables were varying a lot; however, DAS 28 scores after baseline were all within the limits of moderate effect. In the etanercept group we observed statistically significantly better values for all the variables except for erythrocyte sedimentation rate after 6 weeks. At the other times of registration all the variables had significantly better values. Adverse effects were reported in 9 patients in the infliximab group and in 5 in the etanercept group, but no serious adverse effects were reported. 18 patients in the infliximab group (61%) and 10 in the etanercept group (42%) had stopped treatment within two years, either because of adverse effects or lack of effect.

CONCLUSION

In this open study of patients with active rheumatoid arthritis, most experienced a rapid effect of infliximab, but a varying effect later on. In the etanercept group the patients experienced both a rapid and sustained effect among those who tolerated the medication. Compared to what several others have reported, a large number of patients stopped treatment; this may reflect limited experience.

Implications of BCRP modulation on PTZ-induced seizures in mice: Role of ko143 and metformin as adjuvants to lamotrigine

Blood-brain barrier (BBB) efflux transporters' overexpression hinders antiepileptic drug brain entry. Breast cancer resistance protein (BCRP) is a major BBB efflux transporter. In the present work, BCRP's role as a mechanism that might contribute to drug-resistant epilepsy (DRE) in a mouse model of acute seizures was studied with further assessment of the effect of its inhibition by ko143 and metformin (MET) on lamotrigine (LTG) bioavailability and efficacy. 42 male mice divided into 6 groups: G1: Normal control, G2: LTG-injected healthy mice: LTG 20 mg/kg i.p., G3: Acute seizures (A.S) mice: Pentylenetetrazole (PTZ) 50 mg/kg i.p., G4: LTG-treated A.S mice: LTG 20 mg/kg + PTZ 50 mg/kg i.p., G5: Ko143 + LTG treated A.S mice: Ko143 15 mg/kg i.p. before LTG + PTZ, G6: MET + LTG treated A.S mice: MET 200 mg/kg i.p. before LTG + PTZ. Seizures severity, serum, brain LTG, and brain BCRP were assessed. PTZ group experienced the highest seizure frequency and brain BCRP expression. Ko143 and MET groups showed a significant decrease in brain BCRP with subsequent improvement in brain LTG level and better seizure control. BCRP has a significant role in epilepsy resistance and its inhibition with ko143 or MET adds value to DRE management.

Enhancement of cellular immunity in melanoma patients immunized with a peptide from MART-1/Melan A

PURPOSE

In this study, we tested the effectiveness of a melanoma-associated antigen-derived peptide, MART-1(27-35), in eliciting cellular immune responses in vivo in the context of a phase I active immunization protocol. This peptide (AAGIGILTV) corresponds to residues 27-35 from the nonmutated melanoma-associated antigen MART-1/Melan A and is recognized by most melanoma-specific, HLA-A*0201-restricted, tumor-infiltrating lymphocytes. To test the in vivo induction of cytotoxic T lymphocyte (CTL) sensitization, we compared CTL reactivity in vitro from peripheral blood mononuclear cell (PBMC) pools obtained before and after vaccination.

PATIENTS AND METHODS

MART-1(27-35) was administered to HLA-A*0201 melanoma patients subcutaneously in an emulsification with incomplete Freund's adjuvant. A vaccination course included four inoculations of peptide at 3-week intervals. PBMC collected by leukapheresis and separated by Ficoll-Hypaque gradient before and after vaccination were analyzed in 18 patients by in vitro sensitization with MART-1(27-35). To induce MART-1(27-35)-specific CTL, PBMC were incubated with 1 microM peptide (on day 0) and interleukin-2 (IL-2) (300 IU/mL, on days 1 and 4 after each stimulation). At weekly intervals, cells were harvested and an aliquot was cryopreserved for later analysis. The remaining cells were replated and restimulated using irradiated autologous PBMC pulsed with 1 microM of relevant peptide. After three restimulations, all samples from one patient were tested simultaneously for HLA-A*0201-restricted anti-MART-1(27-35) reactivity by microcytotoxicity and cytokine (IFN-gamma) release assays.

RESULTS

Toxicities were minimal and consisted of local irritation at the site of vaccine administration. None of the patients sustained a clinical response. The first eight patients were monitored by inducing CTL reactivity from PBMC obtained preimmunization and after two and four vaccinations. Only two prevaccination cultures were reactive to MART-1, compared with five and seven cultures from PBMC obtained after two and four vaccinations, respectively. Thus, an enhancement in cytotoxic activity could be detected in postvaccination CTL cultures, and serial vaccine administrations appeared to boost the detectability of cytotoxicity in vitro. For completeness, the analysis compared prevaccination with postvaccination PBMC cultures. Specific anti-MART-1(27-35) cytotoxicity (> or = 10 lytic units) could be detected in two prevaccination and 12 postvaccination cultures after two in vitro stimulations. In 15 postvaccination CTL cultures, a more than threefold increase in specific release of IFN-gamma was noted, compared with prevaccination.

DISCUSSION

In vivo administration of a melanoma-associated antigen peptide, emulsified in incomplete Freund's adjuvant, could safely augment CTL reactivity against epitopes commonly expressed by melanoma cells. Although the enhancement of CTL reactivity did not achieve tumor regression, it is possible that the use of recombinant immunogens with increased immunomodulatory capabilities in future clinical trials could reach the threshold of CTL activation necessary for tumor regression.

Phase I trial of a MART-1 peptide vaccine with incomplete Freund's adjuvant for resected high-risk melanoma

Twenty-five patients with high-risk resected stages IIB, III, and IV melanoma were immunized with a vaccine consisting of the minimal epitope, immunodominant 9-amino acid peptide derived from the MART-1 tumor antigen (AAGIGILTV) complexed with incomplete Freund's adjuvant. The last three patients received the MART-1(27-35) peptide with incomplete Freund's adjuvant mixed with CRL 1005, a block copolymer adjuvant. Patients were immunized with increasing doses of the MART-1(27-35) peptide in a Phase I trial to evaluate the toxicity, tolerability, and immune responses to the vaccine. Immunizations were administered every 3 weeks for a total of four injections, preceded by leukapheresis to obtain peripheral blood mononuclear cells for immune analyses, followed by a post-vaccine leukapheresis 3 weeks after the fourth vaccination. Skin testing with peptide and standard delayed-type hypersensitivity skin test reagents was also performed before and after vaccinations. Local pain and granuloma formation were observed in the majority of patients, as were fevers or lethargy of grade 1 or 2. No vaccine-related grade III/IV toxicity was observed. The vaccine was felt to be well tolerated. Twelve of 25 patients were anergic to skin testing at the initiation of the trial, and 13 of 25 developed a positive skin test response to the MART-1(27-35) peptide. Immune responses were measured by release of IFN-gamma in an ELISA assay by effector cells after multiple restimulations of peripheral blood mononuclear cells in the presence of MART-1(27-35) peptide-pulsed antigen-presenting cells. An ELISPOT assay was also developed to measure more quantitatively the change in numbers of peptide-specific effector cells after vaccination. Ten of 22 patients demonstrated an immune response to peptide-pulsed targets or tumor cells by ELISA assay after vaccination, as did 12 of 20 patients by ELISPOT. Nine of 25 patients have relapsed with a median of 16 months of follow-up, and 3 patients in this high-risk group have died. Immune response by ELISA correlated with prolonged relapse-free survival. These data suggest a significant proportion of patients with resected melanoma mount an antigen-specific immune response against a peptide vaccine and support further development of peptide vaccines for melanoma.

[Measures for tuberculosis in compromised hosts--mainly on chemoprophylaxis]

As for the measures for tuberculosis in Japan, BCG inoculation and chemoprophylaxis have been done with emphasis placed on children and young people. Since, however, about 90% are older than 30 years and more than 50% are older than 60 years among the new TB patients, measures, particularly chemoprophylaxis aiming at the middle-old aged people are needed in the future. We discuss the method to select cases for chemoprophylaxis as to the cases of diabetes, collagen diseases and lung cancer administered corticosteroid preparations as well as the cases of Crohn's disease and rheumatoid arthritis administered anti-TNF-alpha among compromised hosts. In diabetics, chemoprophylaxis is necessary for those who show healing of TB despite there being no history of TB treatment. Where a corticosteroid preparation, more than 10 mg in terms of prednisolone is administered over a long period of time for collagen disease and lung cancer, chemoprophylaxis is necessary for those who show healing of TB despite there being no history of TB treatment and those who are suspected of having TB infection by a tuberculin test. In the cases of Crohn's disease and rheumatoid arthritis administered anti-TNF-alpha, chemoprophylaxis is necessary for those who show healing of TB despite those who are suspected of having TB infection by a tuberculin test. The administration period of INH as chemoprophylaxis should preferably be set at 9 months instead of 6 months hitherto used.