An unusual case of spontaneous remission of Hodgkin's disease after a single cycle of COPP-ABV chemotherapy followed by infectious complications

Vanishing bile duct syndrome and immunodeficiency preceding the diagnosis of Hodgkin lymphoma

Vanishing bile duct syndrome (VBDS) in association with Hodgkin lymphoma (HL) is well described but not well understood. We report an unusual case of a 75-year-old patient presenting with biopsy-proven VBDS and immunodeficiency, without identifiable cause, which showed a waxing and waning course, culminating in the development of HL 18 months later. To our knowledge, this is the first adult case in which VBDS preceded the diagnosis of HL by such a long period.

Molecular mimicry of MAGE-A6 and Mycoplasma penetrans HF-2 epitopes in the induction of antitumor CD8+ T-cell responses

A promising vaccine strategy for the treatment of cancer involves the use of vaccines incorporating tumor antigen-derived synthetic peptides that can be coordinately recognized by specific CD4⁺ and CD8⁺ T-cells. Previously, we reported that a MAGE-A6-derived peptide (MAGE-A6_172-187) and its highly-immunogenic and cross-reactive homolog derived from Mycoplasma penetrans HF-2 permease (HF-2_216-229) are promiscuously presented by multiple HLA-DR alleles to responder CD4⁺ T-cells obtained from healthy donors and melanoma patients. Here, we investigated whether these same peptides could concomitantly stimulate cross-reactive MAGE-A6-specific CD8⁺ T-cell responses in vitro using cells isolated from HLA-A*0201 (HLA-A2)⁺ healthy individuals and patients with melanoma. We now show that MAGE-A6_172-187 and, even more so, HF-2_216-229, induce memory CD8⁺ T cells that recognize HLA-A2⁺ MAGE-A6⁺ tumor target cells. The immunogenicity of these peptides was at least partially attributed to their embedded MAGE-A6_176-185 and HF-2_220-229 "homologous" sequences. The functional avidity of HF-2_216-229 peptide-primed CD8⁺ T cells for the MAGE-A6_172-187 peptide was more than 100-fold greater than that of CD8⁺ T cells primed with the corresponding MAGE-A6 peptide. Additionally, these 2 peptides were recognized in interferon γ (IFNγ) and granzyme B ELISPOT assays by CD8⁺ T-cell clones displaying variable T-cell receptor (TCR) Vβ usage. These data suggest that the immune cross-reactivity of the MAGE-A6_172-187 and HF-2_216-229 peptides extends to CD8⁺ T cells, at least in HLA-A2⁺ donors, and supports the potential translational utility of these epitopes in clinical vaccine formulations and for immunomonitoring of cancer patients.

Predictors of successful cancer prevention programs

Finding the optimal use of health-care resources requires the reliable estimation of costs and consequences. Acquiring these estimates may not be difficult for some common treatments. More difficult is the optimization of resources in the area of diagnostics. Only a few attempts have been made to optimize the use of resources in the area of prevention. Several aspects have to be considered when optimizing the resources for prevention: (1) participation rates in structured prevention programs are low, (2), acquiring data on follow-up and outcomes is difficult, (3) there are concerns about the quality of information available to public, and (4), the public is often unaware of scientific assessments of prevention programs. As prevention programs are costly long-term projects, a strategy to select these programs according to possible predictors of success might be useful. The few analyses of cancer prevention in the literature have been directed towards the most common malignant diseases (as assessed by incidence) such as cancer of the breast, colon, lung and prostate. We argue that incidence is a poor marker for selecting secondary prevention programs. Incidence may be a misleading indicator for two reasons: incidence of disease does not predict efficiency of management or good health outcomes, and incidence does not separate clinically significant from non-significant disease. The traditional strategy is based on the assumption that more screening increases the chance of cure. We propose an alternative outcomes model that suggests better disease management justifies new prevention programs. Indicators for better disease management are effective and efficient treatments as well as high-quality screening (sensitivity and specificity) techniques and possibly "side-effects of prevention programs," which provide early signs of success to motivate the patient's participation, to keep up with the program and finally to succeed.

Allogeneic transplantation for Hodgkin lymphoma

The majority of patients with Hodgkin lymphoma (HL) can now expect to be cured with conventional chemo- and/or radio-therapy. However, a subgroup still exists that have poor outcomes, even following dose escalation and autologous stem cell transplantation. Furthermore, patients relapsing after autografting have limited therapeutic options available. Whilst the application of allogeneic transplantation strategies has historically been limited by prohibitive transplant-related mortality, the exploration of reduced intensity approaches has demonstrated the feasibility of delivering allogeneic immunotherapies with more acceptable mortality rates. Although its role remains controversial, we are beginning to re-evaluate the use of allogeneic transplantation in the management of patients with HL and to address a number of critical questions. These include whether a clinically relevant graft-versus-tumour response occurs in HL, and whether subgroups of patients who might benefit from allogeneic approaches can be identified in order to inform development of rational clinical studies. This review focuses on evaluating recent experience with reduced intensity allogeneic approaches in HL in order to inform opinion on its current role and to highlight areas for future investigation.

A mycoplasma peptide elicits heteroclitic CD4+ T cell responses against tumor antigen MAGE-A6

PURPOSE

Although T-helper (Th) epitopes have been previously reported for many tumor antigens, including MAGE-A6, the relevant HLA-DR alleles that present these peptides are expressed by only a minority of patients. The identification of tumor antigenic epitopes presented promiscuously by many HLA-DR alleles would extend the clinical utility of these peptides in vaccines and for the immunomonitoring of cancer patients.

EXPERIMENTAL DESIGN

A neural network algorithm and in vitro sensitization assays were employed to screen candidate peptides for their immunogenicity.

RESULTS

The MAGE-A6(140-170), MAGE-A6(172-187), and MAGE-A6(280-302) epitopes were recognized by CD4+ T cells isolated from the majority of normal donors and melanoma patients evaluated. Peptide-specific CD4+ T cells also recognized autologous antigen-presenting cell pulsed with recombinant MAGE-A6 (rMAGE) protein, supporting the natural processing and MHC presentation of these epitopes. Given the strong primary in vitro sensitization of normal donor CD4+ T cells by the MAGEA6(172-187) epitope, suggestive of potential cross-reactivity against an environmental stimulus, we identified a highly homologous peptide within the Mycoplasma penetrans HF-2 permease (MPHF2) protein. MPHF2 peptide-primed CD4+ T cells cross-reacted against autologous APC pulsed with the MAGE-A6(172-187) peptide or rMAGE protein and recognized HLA-matched MAGE-A6+ melanoma cell lines. These responses seemed heteroclitic in nature because the functional avidity of MPHF2 peptide-primed CD4+ T cells for the MAGE-A6(172-187) peptide was approximately 1,000 times greater than that of CD4+ T cells primed with the corresponding MAGE-A6 peptide.

CONCLUSIONS

We believe that these novel "promiscuous" MAGE-A6/MPHF2 Th epitopes may prove clinically useful in the treatment and/or monitoring of a high proportion of cancer patients.

Correlation of T-cell immune response with spontaneous resolution and subsequent relapse of Hodgkin's lymphoma

To our knowledge, there has been no report of spontaneous regression in a non-immunocompromised adult with classical Hodgkin's lymphoma (HL) in the absence of chemotherapy. We describe spontaneous regression and subsequent relapse of Epstein - Barr virus (EBV)-positive HL in an otherwise healthy male adult. The clinical course was associated with an increase in regulatory T-cell markers within the peripheral blood and diseased lymph node at the time of relapse and with a concomitant reduction in cellular immunity against relevant EBV latent membrane protein tumor-associated antigens. Our findings are in keeping with previous observations that implicate impaired cellular immunity in the immunopathogenesis of EBV-positive HL.

Evidence that amphotericin B mediates reactivation of latent Epstein-Barr virus in Hodgkin's lymphoma allowing cytotoxicity by acyclovir

This brief communication focuses on aspects of a recent case report (Yonsei Med J 2005;46:425-30) on a full and sustained remission of Hodgkin's lymphoma (HL) after a single day of chemotherapy. A septic episode required stopping chemotherapy and starting amphotericin B and acyclovir. Remission evidence was seen within days of starting these. A review of research supporting the notion that amphotericin B can reactivate latent Epstein-Barr virus and thus allow acyclovir to kill infected HL cells is given. Experimental work is required to confirm or refute this possibility. If successful, amphotericin B and acyclovir treatment could be extended to other EBV-driven cancers such as Burkitt's lymphoma, nasopharyngeal carcinoma and the occasional EBV-related epithelial cancer of the breast, colon, prostate, and others.