{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T11:51:06Z","timestamp":1782215466893,"version":"3.54.5"},"reference-count":21,"publisher":"Termedia Sp. z.o.o.","issue":"3","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pol J Pathol"],"abstract":"<jats:p>Malignant melanoma is an aggressive skin cancer, with immune evasion mechanisms contributing to tumour progression. This study evaluated the\u00a0relationship between mismatch repair (MMR) protein loss and the\u00a0expression of\u00a0immune checkpoint molecules programmed death ligand 1 (PD-L1) and galectin-9.&lt;br \/&gt;\nNinety melanoma cases (60 primary, 30 metastatic) were analysed by immunohistochemistry for MMR proteins, PD-L1, and galectin-9. Associations with clinicopathological features and overall survival (OS) were assessed.&lt;br \/&gt;\nMismatch repair protein loss occurred in 5% of\u00a0primary and 16.7% of\u00a0metastatic melanomas (p = 0.015). Programmed death ligand 1 was positive in 18.8% of\u00a0cases, with higher expression in metastatic tumours, but this was not statistically significant (p = 0.106). All PD-L1 positive tumours retained MMR proteins. Galectin-9 expression tended to be higher in tumours with MMR loss and in PD-L1-positive cases, but correlations were not significant. Median OS was  26.0 months, and no variable significantly affected survival in multivariate analysis.&lt;br \/&gt;\nMismatch repair loss was more frequent in metastatic melanomas and associated with higher galectin-9 expression, whereas PD-L1 showed no clear link with MMR status. None of\u00a0the\u00a0associations reached statistical significance, emphasising the\u00a0descriptive and exploratory nature of\u00a0the\u00a0study. &lt;br \/&gt;\nThese findings outline biomarker expression patterns in melanoma and support further investigation in larger cohorts, including patients treated with immune checkpoint inhibitors, to clarify their potential clinical relevance.<\/jats:p>","DOI":"10.5114\/pjp.2025.155817","type":"journal-article","created":{"date-parts":[[2025,11,5]],"date-time":"2025-11-05T09:13:21Z","timestamp":1762334001000},"page":"239-247","source":"Crossref","is-referenced-by-count":0,"title":["Unravelling the\u00a0link between mismatch repair protein deficiency and immune checkpoint markers \u2013 programmed death ligand 1 and galectin-9 expression in malignant melanoma"],"prefix":"10.5114","volume":"76","author":[{"given":"Gizem","family":"Teoman","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Mustafa Emre","family":"Ercin","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Safak","family":"Ersoz","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Savas","family":"Yayli","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Murat","family":"Livaoglu","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"3061","published-online":{"date-parts":[[2025,11,5]]},"reference":[{"key":"ref-1687842","doi-asserted-by":"crossref","unstructured":"Dzwierzynski WW. 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J Am Acad Dermatol 2013; 68: 509-510.","DOI":"10.1016\/j.jaad.2012.09.054"},{"key":"ref-1687849","doi-asserted-by":"crossref","unstructured":"Shimozaki K, Hayashi H, Tanishima S, Horie S, Chida A, Tsugaru K, et al. Concordance analysis of\u00a0microsatellite instability status between polymerase chain reaction based testing and next generation sequencing for solid tumors. Sci Rep 2021; 11: 20003.","DOI":"10.1038\/s41598-021-99364-z"},{"key":"ref-1687850","doi-asserted-by":"crossref","unstructured":"Nebot-Bral L, Coutzac C, Kannouche PL, Chaput N. Why is immunotherapy effective (or not) in patients with MSI\/MMRD tumors? Bull Cancer 2019; 106: 105-113.","DOI":"10.1016\/j.bulcan.2018.08.007"},{"key":"ref-1687851","doi-asserted-by":"crossref","unstructured":"Sunshine JC, Nguyen PL, Kaunitz GJ, Cottrell TR, Berry S, Esandrio J, et al. PD-L1 expression in melanoma: a\u00a0quantitative immunohistochemical antibody comparison. Clin Cancer Res 2017; 23: 4938-4944.","DOI":"10.1158\/1078-0432.CCR-16-1821"},{"key":"ref-1687852","doi-asserted-by":"crossref","unstructured":"Zhang M, Liu C, Li Y, Li H, Zhang W, Liu J, et al. Galectin-9 in cancer therapy: from immune checkpoint ligand to promising therapeutic target. Front Cell Dev Biol 2023; 11: 1332205.","DOI":"10.3389\/fcell.2023.1332205"},{"key":"ref-1687853","doi-asserted-by":"crossref","unstructured":"Maule JG, Clinton LK, Graf RP, Xiao J, Oxnard GR, Ross JS, et al. Comparison of\u00a0PD-L1 tumor cell expression with 22C3, 28-8, and SP142 IHC assays across multiple tumor types.  J Immunother Cancer 2022; 10: e005573.","DOI":"10.1136\/jitc-2022-005573"},{"key":"ref-1687854","doi-asserted-by":"crossref","unstructured":"Saygin I, \u00c7ak\u0131r E, Kazaz SN, G\u00fcvercin AR, Ey\u00fcbo\u011flu \u0130, Ustao\u011flu MM. Immunohistochemical analysis of\u00a0the\u00a0immune checkpoint molecule Galectin-9 in meningiomas. Cukurova Med  J 2024; 49: 600-606.","DOI":"10.17826\/cumj.1455861"},{"key":"ref-1687855","doi-asserted-by":"crossref","unstructured":"Mestrallet G, Brown M, Bozkus CC, Bhardwaj N. Immune escape and resistance to immunotherapy in mismatch repair deficient tumors. Front Immunol 2023; 14: 1210164.","DOI":"10.3389\/fimmu.2023.1210164"},{"key":"ref-1687856","doi-asserted-by":"crossref","unstructured":"Russell BL, Sooklal SA, Malindisa ST, Daka LJ, Ntwasa M. The\u00a0tumor microenvironment factors that promote resistance to immune checkpoint blockade therapy. Front Oncol 2021; 11: 641428.","DOI":"10.3389\/fonc.2021.641428"},{"key":"ref-1687857","doi-asserted-by":"crossref","unstructured":"Diaz LA,\u00a0Le DT. PD-1 blockade in tumors with mismatch- repair deficiency. N Engl J Med 2015; 372: 2509-2520.","DOI":"10.1056\/NEJMoa1500596"},{"key":"ref-1687858","doi-asserted-by":"crossref","unstructured":"Luke JJ, Flaherty KT, Ribas A, Long GV. 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Arch Bronconeumol 2025; S0300-2896(25)00116-4.","DOI":"10.1183\/13993003.congress-2025.PA3553"},{"key":"ref-1687861","doi-asserted-by":"crossref","unstructured":"Enninga EA, Nevala WK, Holtan SG, Leontovich AA, Markovic SN. Galectin-9 modulates immunity by promoting Th2\/M2 differentiation and impacts survival in patients with metastatic melanoma. Melanoma Res 2016; 26: 429-441.","DOI":"10.1097\/CMR.0000000000000281"},{"key":"ref-1687862","doi-asserted-by":"crossref","unstructured":"Wang L, Zhang C, Ji J, Jiao Q. Galectin-9: diverse roles in skin disease. Front Allergy 2025; 6: 1614277.","DOI":"10.3389\/falgy.2025.1614277"}],"container-title":["Polish Journal of Pathology"],"original-title":[],"link":[{"URL":"https:\/\/www.polishjournalofpathology.com\/pdf-211334-136507","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/www.polishjournalofpathology.com\/pdf-211334-136507","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,6,23]],"date-time":"2026-06-23T11:16:05Z","timestamp":1782213365000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.polishjournalofpathology.com\/Unravelling-the-link-between-mismatch-repair-protein-deficiency-and-immune-checkpoint,211334,0,2.html"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,11,5]]},"references-count":21,"journal-issue":{"issue":"3","published-print":{"date-parts":[[2025]]}},"alternative-id":["211334"],"URL":"https:\/\/doi.org\/10.5114\/pjp.2025.155817","relation":{},"ISSN":["1233-9687","2084-9869"],"issn-type":[{"value":"1233-9687","type":"print"},{"value":"2084-9869","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,11,5]]}}}