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DuPont Guerry

Publications and source records attributed to DuPont Guerry.

At least 19 recordsLinked to original sources
PubMed2006

Identifying individuals at high risk of melanoma: a practical predictor of absolute risk.

PURPOSE: We developed a model to estimate the 5-year absolute risk of melanoma to efficiently identify individuals at increased risk of melanoma for potential interventions. PATIENTS AND METHODS: We used data from a case-control study with 718 non-Hispanic white patients with invasive cutaneous melanoma from melanoma clinics in Philadelphia, PA and San Francisco, CA; matched controls were 945 patients from outpatient clinics with similar catchment areas. All participants underwent extensive interviews and skin examinations. We selected easily obtained clinical characteristics and responses to simple questions for study in order to develop sex-specific relative risk models. These models were combined with incidence and mortality rates by United States geographic areas to develop estimates of the absolute risk of developing melanoma within 5 years. RESULTS: Relative risk models yielded an attributable risk of 86% for men and 89% for women, using at most seven variables. Attributable risks did not vary by age, ultraviolet B flux or hours outdoors. The absolute individual risks varied widely, depending on age, other host characteristics, and geographic area. Individual absolute risk can be estimated using a program available online. CONCLUSION: Our procedures allow for estimating the absolute risk of developing melanoma to assist in the identification of patients at high risk. Such high-risk individuals could undergo interventions including a complete skin examination, counseling to avoid sun exposures, regular self and professional surveillance, or participation in prevention trials. It is important to emphasize that these projections are not intended to identify current melanoma cases.

Adult↗
PubMed2006

Human leukocyte antigen-A2-restricted CTL responses to mutated BRAF peptides in melanoma patients.

Mutated BRAF (BRAF(V600E)) is a potential immunotherapeutic target for melanoma because of its tumor specificity and expression in the majority of these lesions derived from different patients. BRAF(V600E) is expressed intracellularly and not on the cell surface, therefore providing a target for T cells but not B cells. Demonstration of patients' T cell responses to BRAF(V600E) would suggest the feasibility of active specific immunotherapy targeting the mutation in these patients. In the present study, BRAF(V600E) peptides with putative binding sites for human leukocyte antigen (HLA)-A2 were used to stimulate T lymphocytes of HLA-A2-positive melanoma patients. Four of five patients with BRAF(V600E)-positive lesions showed lymphoproliferative responses to BRAF(V600E) peptide stimulation. These responses were specific for the mutated epitope and HLA-A2 was restricted in three patients. Lymphocytes from these three patients were cytotoxic against HLA-A2-matched BRAF(V600E)-positive melanoma cells. None of the four patients with BRAF(V600E)-negative lesions and none of five healthy donors had lymphoproliferative responses specific for the mutated epitope. The high prevalence (approximately 50%) of HLA-A2 among melanoma patients renders HLA-A2-restricted BRAF(V600E) peptides attractive candidate vaccines for these patients.

Binding Sites↗
PubMed2006

Predictors of regional nodal disease in patients with thin melanomas.

BACKGROUND: Most melanoma patients present with thin ( 0, vertical growth phase (VGP), male sex, and ulceration were statistically significant predictors of RND. Patients at the highest risk according to a classification tree analysis (VGP and MR>0) had an RND rate of 11.9%. The regression model developed predicted well the SLN status in the validation sample. CONCLUSIONS: Investigation of a large pre-SLN population identified MR>0, ulceration, VGP, and male sex as independently predictive of RND in patients with thin melanomas. These factors may help to identify subgroups of these patients that have clinically significant risks of SLN positivity.

Female↗
PubMed2006

Migration of cytotoxic T lymphocytes toward melanoma cells in three-dimensional organotypic culture is dependent on CCL2 and CCR4.

Studies in experimental animal models have demonstrated that chemokines produced by tumor cells attract chemokine receptor-positive T lymphocytes into the tumor area. However, in cancer patients, the role of chemokines in T lymphocyte trafficking toward human tumor cells is relatively unexplored. In the present study, the migration of a melanoma patient's CTL toward autologous tumor cells has been studied in a novel three-dimensional organotypic melanoma culture. In this model, CTL migrated toward tumor cells, resulting in tumor cell apoptosis. CTL migration was mediated by the CC chemokine receptor (CCR)4 expressed by the CTL and the CC chemokine ligand (CCL)2 secreted by the tumor cells, as evidenced by blockage of CTL migration by CCL2 or antibodies to CCL2 or CCR4. These results were confirmed in a Transwell migration assay in which the CTL actively migrated toward isolated CCL2 and migration was inhibited by anti-CCR4 antibody. These studies, together with previous studies in mice indicating regression of CCL2-transduced tumor cells, suggest that CCL2 may be useful as an immunotherapeutic agent for cancer patients.

Animals↗
PubMed2005

CD8+, HLA-unrestricted, cytotoxic T-lymphocyte line against malignant melanoma.

A CD8+ cytotoxic T lymphocyte (CTL) line was derived from the peripheral blood mononuclear cells of a patient with primary melanoma. The CD8+ CTL line specifically lysed the autologous primary melanoma cells and not the natural killer cell-sensitive K562 cells or lymphokine activated killer cell-sensitive DAUDI cells. When a large panel of human leukocyte antigen (HLA)-matched and -unmatched allogeneic melanoma, glioma, breast and colorectal carcinoma cells was tested as targets in cytolysis assays, 4 HLA-matched and two HLA-unmatched allogeneic metastatic melanoma lines were lysed by the CD8+ CTL. Lysis of autologous and allogeneic melanoma cells was dependent on the effector-to-target cell ratio. Lysis of autologous melanoma cells was not blocked by anti-HLA class I or class II antibodies, confirming that the cytolytic activity of the CD8+ CTL was HLA-unrestricted. CTL lysis of autologous melanoma cells was CD3 (T cell receptor) dependent and FAS-FAS-L, and CD1 independent. Identification of the melanoma-associated antigen recognized by the HLA-unrestricted CTL may provide a vaccine for a broad population of melanoma patients.

Journal Article↗
PubMed2005

CXC chemokine ligand 12 (stromal cell-derived factor 1 alpha) and CXCR4-dependent migration of CTLs toward melanoma cells in organotypic culture.

Studies in experimental animal models have demonstrated that chemokines produced by tumor cells attract chemokine receptor-positive T lymphocytes into the tumor area, which may lead to tumor growth inhibition in vitro and in vivo. However, in cancer patients, the role of chemokines in T lymphocyte trafficking toward human tumor cells is relatively unexplored. In the present study, the role of chemokines and their receptors in the migration of a melanoma patient's CTL toward autologous tumor cells has been studied in a novel organotypic melanoma culture, consisting of a bottom layer of collagen type I with embedded fibroblasts followed successively by a tumor cell layer, collagen/fibroblast separating layer, and, finally, a top layer of collagen with embedded fibroblasts and T cells. In this model, CTL migrated from the top layer through the separating layer toward tumor cells, resulting in tumor cell apoptosis. CTL migration was mediated by chemokine receptor CXCR4 expressed by the CTL and CXCL12 (stromal cell-derived factor 1alpha) secreted by tumor cells, as evidenced by blockage of CTL migration by Abs to CXCL12 or CXCR4, high concentrations of CXCL12 or small molecule CXCR4 antagonist. These studies, together with studies in mice indicating regression of CXCL12-transduced tumor cells, followed by regression of nontransduced challenge tumor cells, suggest that CXCL12 may be useful as an immunotherapeutic agent for cancer patients, when transduced into tumor cells, or fused to anti-tumor Ag Ab or tumor Ag.

Adult↗
PubMed2005

Mitotic rate as a predictor of sentinel lymph node positivity in patients with thin melanomas.

BACKGROUND: Lymphatic mapping and sentinel lymphadenectomy (LM/SL) provide important prognostic information for patients with early-stage melanoma. Although the use of this technique in patients with thin melanomas (< or =1.00 mm) is not routine, risk factors that may predict sentinel lymph node (SLN) positivity in this patient population are under investigation. We sought to determine whether mitotic rate (MR) is associated with SLN positivity in thin-melanoma patients and, therefore, whether it may be used to risk-stratify and select patients for LM/SL. METHODS: Clinical and histopathologic variables were reviewed for 181 patients with thin melanomas who underwent LM/SL from January 1996 through January 2004. Univariate and multivariate logistic regression analyses were performed to identify factors associated with SLN positivity. Risk groups were defined on the basis of the development of a classification tree. RESULTS: The overall SLN positivity rate was 5%. All patients with positive SLNs had an MR of >0. By univariate analysis, MR and thickness were significant predictors of SLN positivity. The association between MR and SLN positivity remained significant controlling for each of the other variables evaluated. On the basis of a classification tree, patients with an MR >0 and tumor thickness > or =.76 mm were identified as a higher-risk group, with an SLN positivity rate of 12.3%. CONCLUSIONS: In patients with thin melanomas, MR >0 seems to be a significant predictor of SLN positivity that may be used to risk-stratify and select patients for LM/SL. To confirm these results, the predictive value of MR for SLN positivity needs to be validated in other populations of thin-melanoma patients.

Female↗
PubMed2004

Thin primary cutaneous malignant melanoma: a prognostic tree for 10-year metastasis is more accurate than American Joint Committee on Cancer staging.

PURPOSE: The majority of invasive primary melanomas are thin (< or = 1.00 mm). Since the current staging system imperfectly predicts outcome in patients with such lesions, we sought to develop a more effective classification scheme to better identify both patients at high risk of metastasis who are candidates for further staging and therapy and those with little risk. PATIENTS AND METHODS: This prospective cohort study included 884 patients who had thin invasive melanomas. A tree-structured analysis of 10-year metastasis was used to develop a new classification scheme. RESULTS: The overall 10-year metastasis rate was 6.5% (95% CI, 4.8% to 8.1%). The prognostic tree defined four risk groups: high-risk: men with vertical growth phase (VGP) lesions that had mitotic rates (MRs) greater than 0, and for whom the 10-year metastasis rate was 31% (22% to 42%; n = 90); moderate-risk: women with VGP lesions that had MRs greater than 0 and for whom the rate was 13% (9% to 18%; n = 136); low-risk: patients with VGP lesions that had MR of 0 for whom the rate was 4% (2% to 7%; n = 247); and minimal-risk: patients with invasive lesions without VGP for whom the rate was 0.5% (0% to 1.2%; n = 411). Survival curves differed significantly among the four groups (P <.001). CONCLUSION: Growth phase, mitotic rate, and sex are important prognostic factors for patients with thin melanomas, and they identify subgroups at substantial risk for metastasis. After validation in other populations, the proposed prognostic tree will be useful in the design of clinical trials and clinical management.

Aged↗
PubMed2004

Assessment of polymorphic variants in the melanocortin-1 receptor gene with cutaneous pigmentation using an evolutionary approach.

The melanocortin-1 receptor gene (MC1R) encodes a membrane-bound receptor protein that is central to melanin synthesis. The coding region of MC1R is highly polymorphic and associations of variants with pigmentation phenotypes and risk for cutaneous neoplasms have been reported. We sought to determine the distribution and frequency of MC1R variants and their relationship to pigmentation characteristics in 179 Caucasian controls from the United States. One hundred thirty-five (75.4%) subjects carried one or more variants, and we determined that carriage of the previously designated "red hair color" (RHC) alleles, R151C, R160W, and D294H was strongly associated with fair pigmentation phenotypes including light hair and eye color, tendency to burn, decreased tendency to tan, and freckling. We used SIFT software to define MC1R protein positions that were predicted intolerant to amino acid substitutions; detected variants that corresponded to intolerant substitutions were D84E, R142H, R151C, I155T, R160W, and D294H. Carriage of one or more of these putative functionally important variants or the frameshift variant ins86A was significantly associated with fair pigmentation phenotypes. Analyses limited to carriage of ins86A and the three non-RHC alleles identified by SIFT were attenuated and no longer reached statistical significance. This is the first study to describe MC1R variants among control subjects from the U.S. Our results indicate that the frequency of variants is similar to that previously observed among non-U.S. Caucasians. Risk variants defined by either the published literature or by evolutionary criteria are strongly and significantly associated with all fair pigmentation phenotypes that were measured.

Adult↗
PubMed2004

Diet and melanoma in a case-control study.

BACKGROUND: Malignant melanoma has been one of the most rapidly increasing cancers within the United States with few modifiable risk factors. This study investigates risk related to dietary factors, which are potentially modifiable. METHODS: Newly diagnosed patients with melanoma (n = 502) were recruited from pigment lesion clinics and controls (n = 565) were recruited from outpatient clinics. To investigate the relationship between melanoma and dietary factors in this case-control study, study subjects were requested to complete a food frequency questionnaire, which assessed diet over the previous year. Using logistic regression, odds ratios (ORs) for melanoma were computed for nutrient and alcohol intake. RESULTS: Persons in high versus low quintiles of energy-adjusted vitamin D, alpha-carotene, beta-carotene, cryptoxanthin, lutein, and lycopene had significantly reduced risk for melanoma (ORs < or = 0.67), which remained after adjustment for presence of dysplastic nevi, education, and skin response to repeated sun exposure. Addition of micronutrients from supplements did not add an additional reduction in risk. High alcohol consumption was associated with an increased risk for melanoma, which remained after adjustment for confounders [OR (95% confidence interval) in highest versus lowest quintiles, 1.65 (1.09-2.49)]. CONCLUSIONS: Diets consisting of foods rich in vitamin D and carotenoids and low in alcohol may be associated with a reduction in risk for melanoma. These analyses should be repeated in large, prospective studies.

Adult↗
PubMed2003

Recombinant CD63/ME491/neuroglandular/NKI/C-3 antigen inhibits growth of established tumors in transgenic mice.

Attempts to vaccinate against tumors can be hindered by the induction of immunological tolerance to the target Ag as a result of Ag expression on normal tissues. In this study, we find that transgenic mice expressing the melanoma-associated Ag CD63/ME491/neuroglandular/NKI/C-3 on their normal tissues do, in fact, exhibit immunological tolerance to the Ag, recapitulating the conditions in cancer patients. In these mice, growth of murine melanoma cells expressing the Ag after gene transfer was inhibited by immunization with Ag-expressing recombinant vaccinia virus combined with IL-2, but not by immunization with the protein alone, anti-idiotypic Abs, or irradiated tumor cells. The effect of the recombinant virus was demonstrated both for nonestablished and established tumors. Infiltration with both CD4(+) and CD8(+) T lymphocytes was significantly more extensive in tumors from experimental mice than in tumors from control mice. MHC class I-positive, but not class I-negative, tumors were inhibited by the vaccine, suggesting that MHC class I-restricted T lymphocytes play a role in the antitumor effects. Abs did not appear to be involved in the vaccine effects. CD63 was immunogenic in 2 of 13 melanoma patients, pointing to the potential of this Ag, combined with IL-2, as a vaccine for melanoma patients.

Animals↗
PubMed2003

A CD4+, HLA-DR7-restricted T-helper lymphocyte clone recognizes an antigen shared by human malignant melanoma and glioma.

CD4(+) Th cells that are restricted by MHC class II molecules play an important role in the induction of antitumor immune responses. We have established a stable CD4(+) Th cell clone (Th35-1A) from the PBMCs of a patient with primary cutaneous melanoma. The Th cell clone is noncytolytic and proliferates specifically in the presence of irradiated autologous melanoma cells or autologous EBV-transformed B cells pulsed with melanoma tumor cell lysates. Th35-1A produces IFN-gamma (a Th1-type cytokine) after autologous tumor cell stimulation, and its proliferative reactivity is HLA class II-restricted. Th cells showed helper activity for PWM responses of PBMCs. Using a panel of HLA class II-matched and unmatched EBV-B cells as APCs and allogeneic melanoma tumor cell lysate as stimulant, DR7 was delineated as the HLA class II restriction element used by the Th cell clone. In agreement with these results, transfection of an allogeneic melanoma cell line with HLA-DR7 isolated from autologous EBV-B cells rendered the cell line stimulatory for Th35-1A cells. Specificity studies using autologous EBV-B cells (EBV-B35) pulsed with a panel of allogeneic tumor cell lysates of various tissue origins indicated that the Th cell clone recognizes an antigen shared by melanoma and glioma cells. The availability of the Th cell clone may lead to the development of new therapies against melanoma, using adoptive Th cell transfer and/or active immunization with a shared Th cell antigen.

Antibodies, Monoclonal↗
PubMed2002

Average midrange ultraviolet radiation flux and time outdoors predict melanoma risk.

Sunlight is the major environmental risk factor for melanoma. Descriptive studies have shown latitudinal variation in population incidence and mortality rates [D. C. Whiteman and A. C. Green, Int. J. Dermatol., 38: 481-489, 1999, and B. K. Armstrong, Australian J. Dermatol., 38 (Suppl. 1): 51-56, 1997]. In analytic studies, individual exposure has been particularly difficult to quantify. Lifetime residential history was coupled with levels of midrange UV radiation (UVB flux) to provide a measure of individual exposure to sunlight thought to be less subject to misclassification and recall bias. Data were analyzed from 718 non-Hispanic white patients with invasive cutaneous melanoma from melanoma clinics in Philadelphia and San Francisco. Matched controls were 945 patients from outpatient clinics with similar catchment areas. The association of melanoma risk and history of UVB flux along with the usual outdoor exposure risk factors were studied. A 10% increase in the average annual UVB flux was associated with a 19% [95% confidence interval (CI), 5-35%] increase in individual odds for melanoma for men and 16% (95% CI, 2-32%) for women. In men, a 10% increase in hours outdoors was associated with a 2.8% (95% CI, 1.2-4.5%) increase in odds. Even in women who could develop a deep tan, a 10% increase in hours outdoors was associated with a 5.8% increase in odds (95% CI, 1.4-10.4%). The association between melanoma risk and average annual UVB flux was strong and consistent for men and for women. The association with total adult hours outdoors was notable for men of all skin types and women who develop a suntan.

Adult↗
PubMed2002

Multiple primary melanoma revisited.

BACKGROUND: Incidence of cutaneous melanoma continues to increase in the Caucasian population worldwide. Approximately 5% of melanoma patients develop additional primary melanoma. This rate is significantly higher than the estimated lifetime risk of an individual for developing the disease (1.4%). These features suggest that a genetic predisposition may underlie multiple primary melanomas (MPMs). Prior studies had identified CDKN2A mutations in a few MPM individuals. The objectives of this study were to determine the frequency of family history of melanoma in MPM cases, to characterize other clinical features including history of other cancer, and to determine the association with functional CDKN2A mutations. METHODS: This study used a case series design. All living patients who had been seen in the Pigmented Lesion Clinic at the University of Pennsylvania and who had more than one primary invasive malignant melanoma or an invasive primary followed by an in situ melanoma were eligible for participation. RESULTS: Individuals with MPM frequently had a family history of melanoma, dysplastic nevi (DN), and/or another cancer including basal cell carcinoma (BCC), and squamous cell carcinoma breast cancer, and a personal history of DN, and basal cell carcinoma. Germline mutations in CDKN2A gene were identified in 8 of 96 MPM cases (8.3%, 95% confidence interval, 6.7-9.9%). CONCLUSIONS: These data indicate that the presence of MPM is associated with a modest incidence of a family history of melanoma, DN, or BCC and a small association with CDKN2A mutations. Therefore, in addition to the MPM index case, other family members can benefit from screening and regular surveillance for melanoma, DN, and BCC.

Adolescent↗
PubMed2002

A polymorphism in the agouti signaling protein gene is associated with human pigmentation.

In mice and humans, binding of alpha-melanocyte--stimulating hormone to the melanocyte-stimulating--hormone receptor (MSHR), the protein product of melanocortin-1 receptor (MC1R) gene, leads to the synthesis of eumelanin. In the mouse, ligation of MSHR by agouti signaling protein (ASP) results in the production of pheomelanin. The role of ASP in humans is unclear. We sought to characterize the agouti signaling protein gene (ASIP) in a group of white subjects, to assess whether ASIP was a determinant of human pigmentation and whether this gene may be associated with increased melanoma risk. We found no evidence of coding-region sequence variation in ASIP, but detected a g.8818A-->G polymorphism in the 3' untranslated region. We genotyped 746 participants in a study of melanoma susceptibility for g.8818A-->G, by means of polymerase chain reaction and restriction fragment--length polymorphism analysis. Among the 147 healthy controls, the frequency of the G allele was.12. Carriage of the G allele was significantly associated with dark hair (odds ratio 1.8; 95% confidence interval [CI] 1.2--2.8) and brown eyes (odds ratio 1.9; 95% CI 1.3--2.8) after adjusting for age, gender, and disease status. ASIP g.8818A-->G was not associated independently with disease status. This is the first report of an association of ASIP with specific human pigmentation characteristics. It remains to be investigated whether the interaction of MC1R and ASIP can enhance prediction of human pigmentation and melanoma risk.

Aging↗
PubMed2002

Pathology review of cases presenting to a multidisciplinary pigmented lesion clinic.

OBJECTIVES: To determine if pathology review, within the context of a multidisciplinary pigmented lesion clinic, results in changes in diagnosis of melanocytic lesions and to ascertain if the change in diagnosis altered clinical management and outcome. METHODS: Retrospective review of pathology reports, progress notes, and diagnoses entered in the University of Pennsylvania (Philadelphia) Pigmented Lesion Clinic database. RESULTS: A total of 5136 primary melanocytic lesions from patients referred to the pigmented lesion clinic between 1991 and 1999 were reviewed by a single pathologist. Of these, 559 (11%) had diagnoses that were changed significantly from the submitting diagnosis, with 120 (2.3%) undergoing a "critical" revision, 63 (1.2%) defined as a change from malignant to benign, and 57 (1.1%) from benign to malignant; 171 (3.3%) remained within the same category (benign or malignant) but had a downgrade in diagnosis (less severe) that would have a significant impact on treatment, prognosis, and research. Likewise, 268 (5.2%) remained within the same category but had an upgrade in diagnosis (more severe) that would have a significant impact on the same parameters. In addition, 257 reexcisions of melanocytic lesions were reviewed, of which 15 (5.8%) were changed from clear to involved margins, while another 16 (6.2%) were changed from involved to clear margins, for a total of 12%. Of the lesions with a critical revision, follow-up was obtained in 98 (83%). The patients in the malignant-to-benign category were followed up for an average of 2.6 years while those in the benign-to-malignant category were followed up for an average of 4.2 years. The change of diagnosis from malignant to benign resulted in 9 patients (17%) being spared a reexcision while 12 patients (23%) were downgraded from a radical to moderate reexcision. The change in diagnosis from benign to malignant resulted in 45 patients (98%) requiring a reexcision after review. Twenty-five of these patients were found to have residual disease in their reexcision specimens or had already had recurrence at the excision site. Furthermore, 7 patients (15%) underwent lymph node dissection or sentinel lymph node biopsy after review. However, none of the nodes were positive for metastatic disease. During this time, 8 patients (17%) in the benign-to-malignant category, and 1 patient (1.9%) in the malignant-to-benign category (who had previously had 4 primary melanomas) developed metastatic disease. CONCLUSIONS: Pathology review of primary melanocytic lesions, within the context of a multidisciplinary pigmented lesion clinic, results in changes in diagnosis in a significant proportion of cases. These changes have important implications for clinical decision making, patient outcome, and research data collection.

Diagnosis, Differential↗