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- Helgadottir, H., et al.
(författare)
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Efficacy of novel immunotherapy regimens in patients with metastatic melanoma with germline CDKN2A mutations
- 2020
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Ingår i: Journal of Medical Genetics. - : BMJ. - 0022-2593 .- 1468-6244. ; 57:5, s. 316-321
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Tidskriftsartikel (refereegranskat)abstract
- Background Inherited CDKN2A mutation is a strong risk factor for cutaneous melanoma. Moreover, carriers have been found to have poor melanoma-specific survival. In this study, responses to novel immunotherapy agents in CDKN2A mutation carriers with metastatic melanoma were evaluated. Methods CDKN2A mutation carriers that have developed metastatic melanoma and undergone immunotherapy treatments were identified among carriers enrolled in follow-up studies for familial melanoma. The carriers' responses were compared with responses reported in phase III clinical trials for CTLA-4 and PD-1 inhibitors. From publicly available data sets, melanomas with somatic CDKN2A mutation were analysed for association with tumour mutational load. Results Eleven of 19 carriers (58%) responded to the therapy, a significantly higher frequency than observed in clinical trials (p=0.03, binomial test against an expected rate of 37%). Further, 6 of the 19 carriers (32%) had complete response, a significantly higher frequency than observed in clinical trials (p=0.01, binomial test against an expected rate of 7%). In 118 melanomas with somatic CDKN2A mutations, significantly higher total numbers of mutations were observed compared with 761 melanomas without CDKN2A mutation (Wilcoxon test, p<0.001). Conclusion Patients with CDKN2A mutated melanoma may have improved immunotherapy responses due to increased tumour mutational load, resulting in more neoantigens and stronger antitumorous immune responses.
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| 2. |
- Mitra, Shamik, et al.
(författare)
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Analysis of DNA methylation patterns in the tumor immune microenvironment of metastatic melanoma
- 2020
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Ingår i: Molecular Oncology. - : Wiley. - 1574-7891 .- 1878-0261. ; 14:5, s. 933-950
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Tidskriftsartikel (refereegranskat)abstract
- The presence of immune cells in the tumor microenvironment has been associated with response to immunotherapies across several cancer types, including melanoma. Despite its therapeutic relevance, characterization of the melanoma immune microenvironments remains insufficiently explored. To distinguish the immune microenvironment in a cohort of 180 metastatic melanoma clinical specimens, we developed a method using promoter CpG methylation of immune cell type-specific genes extracted from genome-wide methylation arrays. Unsupervised clustering identified three immune-methylation clusters with varying levels of immune CpG methylation that are related to patient survival. Matching protein and gene expression data further corroborated the identified epigenetic characterization. Exploration of the possible immune exclusion mechanisms at play revealed likely dependency on MITF protein level and PTEN loss-of-function events for melanomas unresponsive to immunotherapies (immune-low). To understand if melanoma tumors resemble other solid tumors in terms of immune-methylation characteristics, we explored 15 different solid tumor cohorts from TCGA. Low-dimensional projection based on immune cell type-specific methylation revealed grouping of the solid tumors in line with melanoma immune-methylation clusters rather than tumor types. Association of survival outcome with immune cell type-specific methylation differed across tumor and cell types. However, in melanomas immune-cell type-specific methylation was associated with inferior patient survival. Exploration of the immune-methylation patterns in a pan-cancer context suggested that specific immune-microenvironments might occur across the cancer spectrum. Together, our findings underscore the existence of diverse immune microenvironments, which may be informative for future immunotherapeutic applications.
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