Anti-tyrosinase-related protein-2 immune response in vitiligo patients and melanoma patients receiving active-specific immunotherapy.

Several melanosome glycoproteins have been shown to be antigenic in humans. Correlation of antigen-specific immune responses in patients with the autoimmune disease vitiligo, therapy-induced hypopigmentation, and cutaneous melanoma has not been well studied. We examined antibody responses to a melanocyte autoantigen, tyrosinase-related protein-2 (TRP-2), as it is highly expressed in cutaneous melanoma and melanocytes. TRP-2 recombinant protein was synthesized for western blot and affinity anti-TRP-2 enzyme-linked immunosorbent assay. We demonstrated that patients with malignant melanoma, vitiligo, and active-specific immunotherapy-induced depigmentation had significant anti-TRP-2 IgG titers. The highest level of anti-TRP-2 IgG response was found in vitiligo patients. Induction and enhancement of anti-TRP-2 IgG responses were observed in melanoma patients treated with a polyvalent melanoma cell vaccine containing TRP-2. Active-specific immunotherapy could induce and/or augment the TRP-2 IgG antibody titers. Melanoma patients who developed hypopigmentation and had improved survival after polyvalent melanoma cell vaccine had significantly augmented anti-TRP-2 antibody responses compared with patients with poor prognosis. This study demonstrates that TRP-2 autoantigen is immunogenic in humans. TRP-2 antibody responses provide a linkage between autoimmune responses by vitiligo patients and melanoma patients responding to immunotherapy who have induced hypopigmentation.

Is the survival of melanoma patients receiving polyvalent melanoma cell vaccine linked to the human leukocyte antigen phenotype of patients?

PURPOSE: An allogeneic polyvalent melanoma cell vaccine (PMCV) has been shown to be efficacious in improving overall survival of patients with malignant melanoma in a phase II clinical setting. The PMCV consists of three allogeneic melanoma cell lines. The objectives of the study were to determine (1) whether the survival of melanoma patients who received PMCV was related to the patient's human leukocyte antigen (HLA) class I phenotype matching the HLA class I phenotype of the PMCV, and (2) whether PMCV clinical efficacy was correlated to melanoma patients with a particular HLA phenotype(s). MATERIALS AND METHODS: PMCV was given to 69 melanoma patients with American Joint Committee on Cancer (AJCC) stage I to IV disease status. The PMCV and patients lymphocytes were typed for HLA-A and -B. A correlation was made between the HLA expression of PMCV lines and the HLA of patients to their survival status. A second correlation was made between the HLA of patients and survival independent of the PMCV HLA phenotype. RESULTS: Patients whose HLA phenotype (A3/11 and B7/44) matched the PMCV lines had a better overall survival (P < .029). Analysis of HLA expression of patients independent of PMCV HLA to survival showed that HLA-A25 phenotype patients had a significantly better overall survival (P = .006). HLA-B35 patients had a poorer survival outcome (P = .019). CONCLUSION: The studies indicate that overall survival following PMCV treatment in melanoma patients significantly correlates with their HLA phenotypes. These correlations may be related to the host immune response to the PMCV or due to differences in the clinical course of melanoma in patients with different HLA types.

Detection of occult melanoma cells in blood with a multiple-marker polymerase chain reaction assay.

PURPOSE: The objective of the study was to develop a sensitive multimarker polymerase chain reaction (PCR) assay to detect circulating melanoma cells in patient blood. The rationale was that malignant melanoma is heterogeneous in regards to antigen expression. PATIENTS AND METHODS: A PCR assay that uses four melanoma-associated gene markers (tyrosinase, p97, MUC18, and MAGE-3) was developed. Sensitivity and specificity of the PCR assay for individual markers were assessed using 10 melanoma cell lines and peripheral-blood lymphocytes (PBL) from 39 normal volunteers as controls. The assay's sensitivity and specificity were improved using nested primers and Southern blot analysis. Patients (N = 119) with American Joint Committee on Cancer (AJCC) stages I to IV disease were evaluated for circulating melanoma cells using the four gene markers under optimal conditions. RESULTS: All melanoma-associated gene markers were expressed in at least 80% of the melanoma lines, whereas 37 of 39 normal PBL tested negative for all markers; the remaining two PBL were positive for MUC18. Using four markers in the PCR assay was significantly better than using tyrosinase alone. There was a significant correlation between the number of positive PCR markers, AJCC stage of disease, and progression of disease. In all AJCC stages, there were more PCR-positive patients with disease than without disease. CONCLUSION: A multimarker PCR assay is more reliable and sensitive than a single-marker assay for detection of melanoma cells in blood of patients. This assay can provide important insight into tumor progression kinetics without major surgical or conventional radiologic diagnostic procedures.

Suppressor cell activity in a randomized trial of patients receiving active specific immunotherapy with melanoma cell vaccine and low dosages of cyclophosphamide.

Previous studies have shown that melanoma patients develop an immune response to cell surface melanoma-associated antigens. The presence of this antibody response to cell surface antigens has been correlated with a better clinical outcome when melanoma patients are treated with an allogeneic melanoma cell vaccine (MCV) as an active immunotherapy protocol. It was hypothesized that the inability to consistently induce or enhance existing immune responses to melanoma-associated antigens was related to the downregulation by suppressor cells. Patients received treatments of MCV 3 times in a 4-week interval and then every fourth week. The biological response modifier cyclophosphamide (CYP) is an immunomodulator of suppressor T-cell function. In this study we set out to determine whether CYP given prior to MCV could reduce suppressor cell activity during vaccination. In a randomized trial stage II and III melanoma patients (n = 41) were given MCV alone or in conjunction with CYP at dosages of 300, 150, or 75 mg/m2. CYP was given 3 days prior to each MCV treatment. Suppressor cell activity in patients was monitored by a concanavalin A suppressor assay using peripheral blood lymphocytes from serial phlebotomies during a 12-week period of treatment. In each trial group there were patients who had major reduction in suppressor cell activity (greater than 50%). Overall, the greatest reduction in suppressor cell activity occurred in patients receiving 300 mg/m2 CYP compared to the other CYP dosages or MCV alone. For the first two treatments at all CYP dosages there was a greater number of patients showing reduced suppressor cell activity compared to later treatments. In a comparison of patients receiving MCV alone to MCV + CYP 300 mg/m2 phenotypic analysis of lymphocyte subsets showed significant (P = 0.03) reduction in the CD8+CD11B+ (suppressor) cells of the latter group. These studies suggest that CYP can be used at low dosages in conjunction with MCV to reduce suppressor cell activity.

Detection of malignant melanoma with iodine-123 iodoamphetamine.

Iodoamphetamine (IMP) was shown by in vitro assay to have a high uptake by human melanotic melanoma cells, as compared to amelanotic melanoma cells. Eleven patients with proven malignant melanoma (MM) and 3 normal subjects were imaged at 2-4 hr and 16-24 hr after the i.v. injection 5 mCi (185 MBq) of [123I]IMP. One patient had a recurrent tumor that was subsequently shown to be squamous cell carcinoma. The index lesion was not visualized in the three patients with amelanotic melanomas. The index lesion/lesions were visualized in six of the seven other patients, except for 4/16 nodules in one patient. The seventh patient had a large, necrotic melanotic tumor that was not visualized, but an unsuspected lesion in the iliac nodes was detected. Multiple unsuspected lesions were detected in a second patient. While many lesions were seen at 2-4 hr, all lesions (other than a patient with small bowel disease) were seen best at 16-24 hr. No eye uptake was observed in any patient or control subject. Testicular uptake was seen in all males at 16-24 hr. Iodine-123 IMP appears to be a useful agent for the detection and follow-up of patients with melanotic MM.

Cyclophosphamide-induced alterations in human monocyte functions.

This investigation was designed to study the effects of relatively low doses of cyclophosphamide (CY) on monocyte function in patients with surgically resected melanoma. Monocytes taken from patients 3 days after receiving 300 mg, 150 mg, or 75 mg CY/m2 had decreased interleukin-1 (IL-1) production. Production of tumor necrosis factor (TNF)-like molecules by the same monocytes appeared to be enhanced following 300 mg/m2 CY but not after 150 or 75 mg/m2 CY. In vitro studies of the direct effects of CY metabolites (mafosfamide and 4-hydroperoxycyclophosphamide) on human monocytes showed only concomitant decreases in production of IL-1 and TNF-like molecules. This occurred at concentrations that did not obviously affect viability, although monocyte spreading was inhibited. No evidence was obtained for in vitro enhancement of TNF-production. We conclude that CY can affect monocyte function. In vivo it may have both direct effects leading to decreased TNF and IL-1 production and indirect effects through lymphocytic or haematopoietic systems that activate monocytes to enhanced TNF production. The effects are dose-dependent. These CY-induced changes could be responsible in part for some of the alterations in host immunity and tumor resistance that follows administration of the drug.

Disseminated melanoma presenting as a catastrophic event.

The possibility of a patient with malignant melanoma having a catastrophic event as the presenting sign of tumor dissemination cannot be dismissed. Should such an event occur, it would pose not only a risk to the patient, but also a potential risk to others. Since 1971, 712 patients with malignant melanoma have been evaluated. Twenty patients presented with brain metastases and an additional 12 patients developed brain metastases simultaneously with other organ involvement. Four patients (0.6%) had a catastrophic event, such as a stroke or seizure, with no antecedent symptoms. Microstaging of a primary melanoma by the methods of Clark and Breslow, in addition to the recognition of the presence or absence of regional lymph node metastases, provides reliable information for predicting the probability of tumor dissemination. Patients with deep primary melanomas or with lymph node metastases should be advised regarding their participation in potentially hazardous occupations or recreations.