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1.
JAMA ; 319(11): 1143-1157, 2018 03 20.
Artículo en Inglés | MEDLINE | ID: mdl-29558557

RESUMEN

Importance: Exposure to UV radiation, especially in childhood, increases skin cancer risk. Objective: To systematically review the evidence on the benefits and harms of behavioral counseling for skin cancer prevention to inform the US Preventive Services Task Force (USPSTF). Data Sources: Cochrane Central Register of Controlled Trials, MEDLINE, and PubMed were searched for studies published from January 2009 to March 31, 2016, for skin cancer prevention and from August 2005 to March 31, 2016, for skin self-examination. Surveillance in targeted publications was conducted through February 14, 2018. Studies included in previous USPSTF reports were reevaluated for inclusion. Study Selection: Fair- and good-quality studies of primary care-relevant behavioral interventions focused on improving skin cancer outcomes, intermediate outcomes, or skin cancer prevention and self-examination behaviors. Data Extraction and Synthesis: Two investigators independently reviewed abstracts and full-text articles and extracted data into evidence tables. Results were qualitatively summarized but not pooled because of heterogeneity of measures. Main Outcomes and Measures: Skin cancer, sunburn, precursor skin lesions, sun protection behaviors, and any harms from interventions. Results: Twenty-one trials in 27 publications were included (N = 20 561). No studies assessed skin cancer outcomes in pediatric populations; 1 adult trial (n = 1356) promoting skin self-examination found no significant difference in participants diagnosed with melanoma in the intervention group vs the control group at 12-month follow-up (0 vs 1 diagnosis). There was no consistent improvement in prevention of sunburn for children (3 trials [n = 2508]) or adults (6 trials [n = 3959]). There were small to moderate increases in sun protection behavior in pediatric populations (6 trials [n = 4252]) and adults (12 trials [n = 13 099]) and small increases in skin self-examination in adults (11 trials [n = 7771]; odds ratios, 1.16-2.6). One of 3 trials of indoor tanning found an intervention effect; an appearance-focused intervention (n = 430) resulted in a smaller increase in mean indoor tanning sessions at 6 months in the intervention group vs the control group. Harms were rarely reported: 1 trial of skin self-examination (n = 1356) found an increase in skin procedures in the intervention group vs the control group at 6 months (8.0% vs 3.6%, P < .001) but not between 6 and 12 months (3.9% vs 3.3%, P = .50), and 1 trial (n = 217) found no between-group difference in skin cancer worry (28.9% vs 18.4%, P = .16). Conclusions and Relevance: Behavioral interventions can increase sun protection behavior, but there is no consistent evidence that interventions are associated with a reduction in the frequency of sunburn in children or adults and minimal evidence on skin cancer outcomes. Intervention can increase skin self-examination in adults but may lead to increased skin procedures without detecting additional atypical nevi or skin cancers.


Asunto(s)
Consejo/métodos , Conductas Relacionadas con la Salud , Neoplasias Cutáneas/prevención & control , Quemadura Solar/prevención & control , Adolescente , Adulto , Niño , Humanos , Lesiones Precancerosas/prevención & control , Factores de Riesgo , Autoexamen/efectos adversos , Pigmentación de la Piel , Protectores Solares
2.
Sci Immunol ; 2(8)2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28367538

RESUMEN

Adoptively transferred tumor-specific cells can mediate tumor regression in cancers refractory to conventional therapy. Autologous polyclonal tumor-specific cytotoxic T cells (CTL) generated from peripheral blood and infused into patients with metastatic melanoma show enhanced persistence, compared to equivalent numbers of more extensively expanded monoclonal CTL, and are associated with complete remissions (CR) in select patients. We applied high-throughput T cell receptor Vß sequencing (HTTCS) to identify individual clonotypes within CTL products, track them in vivo post-infusion and then deduce the pre-adoptive transfer (endogenous) frequencies of cells ultimately responsible for tumor regression. The summed in vivo post-transfer frequencies of the top 25 HTTCS-defined clonotypes originally detected in the infused CTL population were comparable to enumeration by binding of antigen peptide-HLA multimers, revealing quantitative HTTCS is a reliable, multimer-independent alternative. Surprisingly, the polyclonal CTL products were composed predominantly of clonotypes that were of very low frequency (VLF) in the endogenous samples, often below the limit of HTTCS detection (0.001%). In patients who achieved durable CRs, the composition of transferred CTLs was dominated (57-90%) by cells derived from a single VLF clonotype. Thus, HTTCS now reveals that tumor-specific CTL enabling long-term tumor control originate from endogenous VLF populations that exhibit proliferative/survival advantages. Along with results indicating that naïve cell populations are most likely to contain cells that exist at VLF within the repertoire, our results provide a strong rationale for favoring T cells arising from VLF populations and with early-differentiation phenotypes when selecting subset populations for adoptive transfer.

3.
J Exp Med ; 213(7): 1133-9, 2016 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-27242164

RESUMEN

Adoptive transfer of peripheral blood-derived, melanoma-reactive CD8(+) cytotoxic T lymphocytes (CTLs) alone is generally insufficient to eliminate bulky tumors. Similarly, monotherapy with anti-CTLA4 infrequently yields sustained remissions in patients with metastatic melanoma. We postulated that a bolus of enhanced IL-21-primed polyclonal antigen-specific CTL combined with CTLA4 blockade might boost antitumor efficacy. In this first-in-human case study, the combination successfully led to a durable complete remission (CR) in a patient whose disease was refractory to both monoclonal CTL and anti-CTLA4. Long-term persistence and sustained anti-tumor activity of transferred CTL, as well as responses to nontargeted antigens, confirmed mutually beneficial effects of the combined treatment. In this first-in-human study, Chapuis et al. demonstrate that the combination of adoptive cellular therapy with CTLA4 blockade induces long-term remission in a melanoma patient resistant to both modalities administered serially and individually.


Asunto(s)
Traslado Adoptivo/métodos , Linfocitos T CD8-positivos/trasplante , Antígeno CTLA-4/inmunología , Interleucinas/inmunología , Melanoma , Femenino , Humanos , Masculino , Melanoma/inmunología , Melanoma/terapia , Persona de Mediana Edad , Metástasis de la Neoplasia
4.
J Clin Oncol ; 34(31): 3787-3795, 2016 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-27269940

RESUMEN

Purpose Peripheral blood-derived antigen-specific cytotoxic T cells (CTLs) provide a readily available source of effector cells that can be administered with minimal toxicity in an outpatient setting. In metastatic melanoma, this approach results in measurable albeit modest clinical responses in patients resistant to conventional therapy. We reasoned that concurrent cytotoxic T-cell lymphocyte antigen-4 (CTLA-4) checkpoint blockade might enhance the antitumor activity of adoptively transferred CTLs. Patients and Methods Autologous MART1-specific CTLs were generated by priming with peptide-pulsed dendritic cells in the presence of interleukin-21 and enriched by peptide-major histocompatibility complex multimer-guided cell sorting. This expeditiously yielded polyclonal CTL lines uniformly expressing markers associated with an enhanced survival potential. In this first-in-human strategy, 10 patients with stage IV melanoma received the MART1-specific CTLs followed by a standard course of anti-CTLA-4 (ipilimumab). Results The toxicity profile of the combined treatment was comparable to that of ipilimumab monotherapy. Evaluation of best responses at 12 weeks yielded two continuous complete remissions, one partial response (PR) using RECIST criteria (two PRs using immune-related response criteria), and three instances of stable disease. Infused CTLs persisted with frequencies up to 2.9% of CD8+ T cells for as long as the patients were monitored (up to 40 weeks). In patients who experienced complete remissions, PRs, or stable disease, the persisting CTLs acquired phenotypic and functional characteristics of long-lived memory cells. Moreover, these patients also developed responses to nontargeted tumor antigens (epitope spreading). Conclusion We demonstrate that combining antigen-specific CTLs with CTLA-4 blockade is safe and produces durable clinical responses, likely reflecting both enhanced activity of transferred cells and improved recruitment of new responses, highlighting the promise of this strategy.


Asunto(s)
Antígeno CTLA-4/inmunología , Inmunoterapia Adoptiva/métodos , Interleucinas/inmunología , Ipilimumab/uso terapéutico , Melanoma/terapia , Linfocitos T Citotóxicos/inmunología , Adulto , Anciano , Antineoplásicos Inmunológicos/uso terapéutico , Terapia Combinada , Femenino , Humanos , Ipilimumab/inmunología , Masculino , Melanoma/inmunología , Persona de Mediana Edad , Inducción de Remisión
5.
J Immunother Cancer ; 2(1): 36, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25317334

RESUMEN

BACKGROUND: Adoptive T cell therapy represents an attractive modality for the treatment of patients with cancer. Peripheral blood mononuclear cells have been used as a source of antigen specific T cells but the very low frequency of T cells recognizing commonly expressed antigens such as NY-ESO-1 limit the applicability of this approach to other solid tumors. To overcome this, we tested a strategy combining IL-21 modulation during in vitro stimulation with first-in-class use of tetramer-guided cell sorting to generate NY-ESO-1 specific cytotoxic T lymphocytes (CTL). METHODS: CTL generation was evaluated in 6 patients with NY-ESO-1 positive sarcomas, under clinical manufacturing conditions and characterized for phenotypic and functional properties. RESULTS: Following in vitro stimulation, T cells stained with NY-ESO-1 tetramer were enriched from frequencies as low as 0.4% to >90% after single pass through a clinical grade sorter. NY-ESO-1 specific T cells were generated from all 6 patients. The final products expanded on average 1200-fold to a total of 36 billion cells, were oligoclonal and contained 67-97% CD8(+), tetramer(+) T cells with a memory phenotype that recognized endogenous NY-ESO-1. CONCLUSION: This study represents the first series using tetramer-guided cell sorting to generate T cells for adoptive therapy. This approach, when used to target more broadly expressed tumor antigens such as WT-1 and additional Cancer-Testis antigens will enhance the scope and feasibility of adoptive T cell therapy.

6.
PLoS One ; 9(5): e96565, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24794217

RESUMEN

OBJECTIVE: The immune response to pancreatic ductal adenocarcinoma (PDA) may play a role in defining its uniquely aggressive biology; therefore, we sought to clearly define the adaptive immune infiltrate in PDA. DESIGN: We used immunohistochemistry and flow cytometry to characterize the immune infiltrate in human PDA and compared our findings to the patients' peripheral blood. RESULTS: In contrast to the myeloid cell predominant infiltrate seen in murine models, T cells comprised the majority of the hematopoietic cell component of the tumor stroma in human PDA. Most intratumoral CD8+ T cells exhibited an antigen-experienced effector memory cell phenotype and were capable of producing IFN-γ. CD4+ regulatory T cells (Treg) and IL-17 producing T helper cells were significantly more prevalent in tumor than in blood. Consistent with the association with reduced survival in previous studies, we observed higher frequencies of both myeloid cells and Treg in poorly differentiated tumors. The majority of intratumoral T cells expressed the co-inhibitory receptor programmed death-1 (PD-1), suggesting one potential mechanism through which PDA may evade antitumor immunity. Successful multimodal neoadjuvant therapy altered the immunoregulatory balance and was associated with reduced infiltration of both myeloid cells and Treg. CONCLUSION: Our data show that human PDA contains a complex mixture of inflammatory and regulatory immune cells, and that neoadjuvant therapy attenuates the infiltration of intratumoral cells associated with immunosuppression and worsened survival.


Asunto(s)
Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/inmunología , Antineoplásicos/uso terapéutico , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/inmunología , Terapia Neoadyuvante/métodos , Páncreas/patología , Adenocarcinoma/patología , Adulto , Anciano , Anciano de 80 o más Años , Linfocitos T CD4-Positivos/efectos de los fármacos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/patología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/patología , Carcinoma Ductal Pancreático/patología , Femenino , Factor Estimulante de Colonias de Granulocitos y Macrófagos/inmunología , Humanos , Interferón gamma/inmunología , Interleucina-17/inmunología , Masculino , Persona de Mediana Edad , Páncreas/efectos de los fármacos , Páncreas/inmunología , Receptor de Muerte Celular Programada 1/inmunología , Linfocitos T Reguladores/efectos de los fármacos , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/patología , Microambiente Tumoral/efectos de los fármacos
7.
Cancer Immunol Res ; 2(1): 27-36, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24432305

RESUMEN

Merkel cell carcinoma (MCC) is an aggressive skin cancer that typically requires the persistent expression of Merkel cell polyomavirus (MCPyV) oncoproteins that can serve as ideal immunotherapeutic targets. Several immune evasion mechanisms are active in MCC including down-regulation of HLA class-I expression on tumor cells and dysfunctional endogenous MCPyV-specific CD8 T cell responses. To overcome these obstacles, we combined local and systemic immune therapies in a 67-year-old man, who developed metastatic MCPyV-expressing MCC. Intralesional IFNß-1b or targeted single-dose radiation was administered as a pre-conditioning strategy to reverse the down-regulation of HLA-I expression noted in his tumors and to facilitate the subsequent recognition of tumor cells by T cells. This was followed by the adoptive transfer of ex vivo expanded polyclonal, polyomavirus-specific T cells as a source of reactive antitumor immunity. The combined regimen was well-tolerated and led to persistent up-regulation of HLA-I expression in the tumor and a durable complete response in two of three metastatic lesions. Relative to historical controls, the patient experienced a prolonged period without development of additional distant metastases (535 days compared to historic median of 200 days, 95% confidence interval = 154-260 days). The transferred CD8(+) T cells preferentially accumulated in the tumor tissue, remained detectable and functional for >200 days, persisted with an effector phenotype, and exhibited evidence of recent in vivo activation and proliferation. The combination of local and systemic immune stimulatory therapies was well-tolerated and may be a promising approach to overcome immune evasion in virus-driven cancers.


Asunto(s)
Carcinoma de Células de Merkel/inmunología , Carcinoma de Células de Merkel/terapia , Antígenos de Histocompatibilidad Clase I/inmunología , Inmunoterapia Adoptiva , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/terapia , Especificidad del Receptor de Antígeno de Linfocitos T/inmunología , Subgrupos de Linfocitos T/inmunología , Anciano , Antígenos Transformadores de Poliomavirus/inmunología , Antígenos Transformadores de Poliomavirus/metabolismo , Carcinoma de Células de Merkel/diagnóstico , Carcinoma de Células de Merkel/patología , Regulación hacia Abajo , Antígenos de Histocompatibilidad Clase I/metabolismo , Humanos , Inmunohistoquímica , Masculino , Poliomavirus de Células de Merkel/inmunología , Metástasis de la Neoplasia , Neoplasias Cutáneas/diagnóstico , Neoplasias Cutáneas/patología , Linfocitos T Citotóxicos/inmunología , Resultado del Tratamiento
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