{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,23]],"date-time":"2026-10-23T21:07:31Z","timestamp":1792789651980,"version":"4.5.0"},"reference-count":43,"publisher":"MDPI AG","issue":"19","license":[{"start":{"date-parts":[[2026,10,1]],"date-time":"2026-10-01T00:00:00Z","timestamp":1790812800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Danish Cancer Society","id":[{"id":"https:\/\/ror.org\/03ytt7k16","id-type":"ROR","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/03ytt7k16","id-type":"ROR","asserted-by":"publisher"}]},{"name":"The Danish Lymphoma Group"},{"name":"Department of Clinical Medicine at Aarhus University","id":[{"id":"https:\/\/ror.org\/01aj84f44","id-type":"ROR","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/01aj84f44","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Thora and Viggo Groves Memorial Foundation"},{"name":"Rieck-Andersen\u2019s Family Foundation"},{"name":"Eva and Henry Fr\u00e6nkels Mindefond Memorial Foundation","id":[{"id":"https:\/\/ror.org\/02f0jr828","id-type":"ROR","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/04wf7sx08","id-type":"ROR","asserted-by":"publisher"}]},{"name":"NEYE Foundation"},{"name":"The Harboe Foundation"},{"id":[{"id":"https:\/\/ror.org\/059hdm253","id-type":"ROR","asserted-by":"publisher"}]},{"name":"The Family Erichsen\u2019s Memorial Foundation","id":[{"id":"https:\/\/ror.org\/0275xpz44","id-type":"ROR","asserted-by":"crossref"}]},{"id":[{"id":"https:\/\/ror.org\/03njeds29","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Doctor Sofus Carl Emil Friis and Wife Olga Doris Friis\u2019 Grant"},{"name":"Farmer of \u201c\u00d8lufg\u00e5rd\u201d Peder Nielsen Kristensens Memorial Foundation"},{"name":"Arvid Nielssons Foundation"},{"id":[{"id":"https:\/\/ror.org\/00a59ax11","id-type":"ROR","asserted-by":"publisher"}]},{"name":"Danielsens Foundation"},{"name":"Merchant L.F. Foghts Foundation,"},{"name":"King Christian X's Foundation"},{"name":"Merchant Einar Willumsen\u2019s Memorial Foundation."}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Mol. Sci.","IJMS"],"abstract":"<jats:p>Follicular lymphoma (FL) is an indolent B-cell malignancy typically associated with favourable outcomes and prolonged survival. However, histological transformation (HT) occurs in a subset of patients and significantly worsens survival outcomes, markedly altering the disease course. Currently, no clinical or molecular predictors of HT are available. We sought to evaluate the potential of Serpin family E member 1 (PAI-1) as a prognostic biomarker of HT in FL, with expression levels assessed by immunohistochemistry and quantified using digital image analysis. PAI-1 expression was evaluated in diagnostic lymphoma biopsies from 30 FL patients with no record of subsequent HT with a minimum follow-up of 10 years, ranging from 10.1 to 24.8 years (non-transforming FL, nt-FL), and 18 patients with subsequent HT occurring 0.7 to 14.6 years after diagnosis (subsequently transforming FL, st-FL); furthermore, the paired high-grade biopsy from the time of HT (transformed FL, tFL) was included. No significant differential expression patterns were identified comparing nt-FL, st-FL and tFL samples. However, high intrafollicular PAI-1 expression at FL diagnosis correlated with no transformation events observed. We believe high intrafollicular PAI-1 expression at presentation might define a minor subgroup of FL patients with reduced risk of HT.<\/jats:p>","DOI":"10.3390\/ijms27198814","type":"journal-article","created":{"date-parts":[[2026,10,2]],"date-time":"2026-10-02T09:10:48Z","timestamp":1790932248000},"page":"8814","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Intrafollicular PAI-1 Expression Is Associated with Absence of Histological Transformation During Long-Term Follow-Up in Follicular Lymphoma"],"prefix":"10.3390","volume":"27","author":[{"ORCID":"https:\/\/orcid.org\/0009-0001-4076-6516","authenticated-orcid":false,"given":"Cecilie","family":"Dohrmann","sequence":"first","affiliation":[{"name":"Department of Haematology, Aarhus University Hospital, 8200 Aarhus, Denmark"},{"name":"Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4086-5183","authenticated-orcid":false,"given":"Marie Hairing","family":"Enemark","sequence":"additional","affiliation":[{"name":"Department of Haematology, Aarhus University Hospital, 8200 Aarhus, Denmark"},{"name":"Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Caroline Maren Stengaard","family":"Jensen","sequence":"additional","affiliation":[{"name":"Department of Haematology, Aarhus University Hospital, 8200 Aarhus, Denmark"},{"name":"Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristina Lystlund","family":"Lauridsen","sequence":"additional","affiliation":[{"name":"Department of Pathology, Aarhus University Hospital, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Trine Lindhardt","family":"Plesner","sequence":"additional","affiliation":[{"name":"Department of Pathology, Copenhagen University Hospital, 2100 Copenhagen, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2158-3885","authenticated-orcid":false,"given":"Stephen Jacques","family":"Hamilton-Dutoit","sequence":"additional","affiliation":[{"name":"Department of Pathology, Aarhus University Hospital, 8200 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5089-3271","authenticated-orcid":false,"given":"Maja","family":"Ludvigsen","sequence":"additional","affiliation":[{"name":"Department of Haematology, Aarhus University Hospital, 8200 Aarhus, Denmark"},{"name":"Department of Clinical Medicine, Aarhus University, 8000 Aarhus, Denmark"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,10,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e473","DOI":"10.3747\/co.26.4625","article-title":"Incidence and mortality trends and geographic patterns of follicular lymphoma in Canada","volume":"26","author":"Le","year":"2019","journal-title":"Curr. 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