{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,10]],"date-time":"2026-02-10T02:28:02Z","timestamp":1770690482210,"version":"3.49.0"},"reference-count":39,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2021,6,18]],"date-time":"2021-06-18T00:00:00Z","timestamp":1623974400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>Tumor resection represents the only curative treatment option for patients with biliary tract cancers (BTCs), including intrahepatic cholangiocarcinoma (CCA), perihilar and extrahepatic CCA and gallbladder cancer. However, many patients develop early tumor recurrence and are unlikely to benefit from surgery. Therefore, markers to identify ideal surgical candidates are urgently needed. Circulating programmed cell death 1 ligand 1 (PD-L1) has recently been associated with different malignancies, including pancreatic cancer which closely resembles BTC in terms of patients\u2019 prognosis and tumor biology. Here, we aim at evaluating a potential role of circulating PD-L1 as a novel biomarker for resectable BTC. Methods: Serum levels of PD-L1 were analyzed by ELISA in 73 BTC patients and 42 healthy controls. Results: Circulating levels of preoperative PD-L1 were significantly lower in patients with BTC compared to controls. Patients with low PD-L1 levels displayed a strong trend towards an impaired prognosis, and circulating PD-L1 was negatively correlated with experimental markers of promalignant tumor characteristics such as CCL1, CCL21, CCL25 and CCL26. For 37 out of 73 patients, postoperative PD-L1 levels were available. Interestingly, after tumor resection, circulating PD-L1 raised to almost normal levels. Notably, patients with further decreasing PD-L1 concentrations after surgery showed a trend towards an impaired postoperative outcome. Conclusion: Circulating PD-L1 levels were decreased in patients with resectable BTC. Lack of normalization of PD-L1 levels after surgery might identify patients at high risk for tumor recurrence or adverse outcome.<\/jats:p>","DOI":"10.3390\/ijms22126569","type":"journal-article","created":{"date-parts":[[2021,6,18]],"date-time":"2021-06-18T11:19:20Z","timestamp":1624015160000},"page":"6569","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Levels of Circulating PD-L1 Are Decreased in Patients with Resectable Cholangiocarcinoma"],"prefix":"10.3390","volume":"22","author":[{"given":"Christoph","family":"Roderburg","sequence":"first","affiliation":[{"name":"Department of Hepatology & Gastroenterology, Campus Virchow Klinikum and Campus Charit\u00e9 Mitte, Charit\u00e9 University Medicine Berlin, 13353 Berlin, Germany"},{"name":"Clinic for Gastroenterology, Hepatology and Infectious Diseases, University Hospital D\u00fcsseldorf, Medical Faculty of Heinrich Heine University D\u00fcsseldorf, 40225 D\u00fcsseldorf, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2799-2287","authenticated-orcid":false,"given":"Sven H.","family":"Loosen","sequence":"additional","affiliation":[{"name":"Clinic for Gastroenterology, Hepatology and Infectious Diseases, University Hospital D\u00fcsseldorf, Medical Faculty of Heinrich Heine University D\u00fcsseldorf, 40225 D\u00fcsseldorf, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jan","family":"Bednarsch","sequence":"additional","affiliation":[{"name":"Department of Visceral and Transplantation Surgery, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Patrick H.","family":"Alizai","sequence":"additional","affiliation":[{"name":"Department of Visceral and Transplantation Surgery, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1670-7487","authenticated-orcid":false,"given":"Anjali A.","family":"Roeth","sequence":"additional","affiliation":[{"name":"Department of Visceral and Transplantation Surgery, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sophia M.","family":"Schmitz","sequence":"additional","affiliation":[{"name":"Department of Visceral and Transplantation Surgery, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mihael","family":"Vucur","sequence":"additional","affiliation":[{"name":"Clinic for Gastroenterology, Hepatology and Infectious Diseases, University Hospital D\u00fcsseldorf, Medical Faculty of Heinrich Heine University D\u00fcsseldorf, 40225 D\u00fcsseldorf, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8149-8087","authenticated-orcid":false,"given":"Mark","family":"Luedde","sequence":"additional","affiliation":[{"name":"KGP Bremerhaven, 27568 Bremerhaven, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pia","family":"Paffenholz","sequence":"additional","affiliation":[{"name":"Department of Urology, University Hospital Cologne, Kerpener Stra\u00dfe 62, 50937 Cologne, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6206-0226","authenticated-orcid":false,"given":"Frank","family":"Tacke","sequence":"additional","affiliation":[{"name":"Department of Hepatology & Gastroenterology, Campus Virchow Klinikum and Campus Charit\u00e9 Mitte, Charit\u00e9 University Medicine Berlin, 13353 Berlin, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Christian","family":"Trautwein","sequence":"additional","affiliation":[{"name":"Department of Medicine III, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tom F.","family":"Ulmer","sequence":"additional","affiliation":[{"name":"Department of Visceral and Transplantation Surgery, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ulf Peter","family":"Neumann","sequence":"additional","affiliation":[{"name":"Department of Visceral and Transplantation Surgery, University Hospital RWTH Aachen, Pauwelsstrasse 30, 52074 Aachen, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tom","family":"Luedde","sequence":"additional","affiliation":[{"name":"Clinic for Gastroenterology, Hepatology and Infectious Diseases, University Hospital D\u00fcsseldorf, Medical Faculty of Heinrich Heine University D\u00fcsseldorf, 40225 D\u00fcsseldorf, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2168","DOI":"10.1016\/S0140-6736(13)61903-0","article-title":"Cholangiocarcinoma","volume":"383","author":"Razumilava","year":"2014","journal-title":"Lancet"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1111\/liv.14100","article-title":"Medical treatment for cholangiocarcinoma","volume":"39","author":"Adeva","year":"2019","journal-title":"Liver Int."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"590","DOI":"10.1245\/s10434-007-9687-y","article-title":"Prognosis of perihilar cholangiocarcinoma: Hilar bile duct cancer versus intrahepatic cholangiocarcinoma involving the hepatic 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Care"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/22\/12\/6569\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T06:18:40Z","timestamp":1760163520000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/22\/12\/6569"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,18]]},"references-count":39,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2021,6]]}},"alternative-id":["ijms22126569"],"URL":"https:\/\/doi.org\/10.3390\/ijms22126569","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,6,18]]}}}