{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,28]],"date-time":"2026-01-28T07:38:37Z","timestamp":1769585917441,"version":"3.49.0"},"reference-count":41,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,2,23]],"date-time":"2023-02-23T00:00:00Z","timestamp":1677110400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Research foundation grant","award":["SCHR 1288\/6-1."],"award-info":[{"award-number":["SCHR 1288\/6-1."]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JCM"],"abstract":"<jats:p>Solid tumors have an altered metabolism with a so-called inside-out pH gradient (decreased pHe &lt; increased pHi). This also signals back to tumor cells via proton-sensitive ion channels or G protein-coupled receptors (pH-GPCRs) to alter migration and proliferation. Nothing, however, is known about the expression of pH-GPCRs in the rare form of peritoneal carcinomatosis. Paraffin-embedded tissue samples of a series of 10 patients with peritoneal carcinomatosis of colorectal (including appendix) origin were used for immunohistochemistry to study the expression of GPR4, GPR65, GPR68, GPR132, and GPR151. GPR4 was just expressed weakly in 30% of samples and expression was significantly reduced as compared to GPR56, GPR132, and GPR151. Furthermore, GPR68 was only expressed in 60% of tumors and showed significantly reduced expression as compared to GPR65 and GPR151. This is the first study on pH-GPCRs in peritoneal carcinomatosis, which shows lower expression of GPR4 and GPR68 as compared to other pH-GPCRs in this type of cancer. It may give rise to future therapies targeting either the TME or these GPCRs directly.<\/jats:p>","DOI":"10.3390\/jcm12051803","type":"journal-article","created":{"date-parts":[[2023,2,24]],"date-time":"2023-02-24T01:37:52Z","timestamp":1677202672000},"page":"1803","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Expression of pH-Sensitive GPCRs in Peritoneal Carcinomatosis of Colorectal Cancer\u2014First Results"],"prefix":"10.3390","volume":"12","author":[{"given":"Philipp","family":"von Breitenbuch","sequence":"first","affiliation":[{"name":"Department of Surgery, Elblandklinikum Radebeul, 01445 Radebeul, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bernadett","family":"Kurz","sequence":"additional","affiliation":[{"name":"Department of Dermatology, University Medical Center Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Susanne","family":"Wallner","sequence":"additional","affiliation":[{"name":"Department of Dermatology, University Medical Center Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Florian","family":"Zeman","sequence":"additional","affiliation":[{"name":"Center for Clinical Studies, University Medical Center Regensburg, 93053 Regensburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6761-0247","authenticated-orcid":false,"given":"Christoph","family":"Brochhausen","sequence":"additional","affiliation":[{"name":"Institute of Pathology, University Medical Center Regensburg, 93053 Regensburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hans-J\u00fcrgen","family":"Schlitt","sequence":"additional","affiliation":[{"name":"Department of Surgery, University Medical Center Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2820-1942","authenticated-orcid":false,"given":"Stephan","family":"Schreml","sequence":"additional","affiliation":[{"name":"Department of Dermatology, University Medical Center Regensburg, Franz-Josef-Strau\u00df-Allee 11, 93053 Regensburg, Germany"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,2,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"786","DOI":"10.1038\/nrc1713","article-title":"The role of disturbed pH dynamics and the Na+\/H+ exchanger in metastasis","volume":"5","author":"Cardone","year":"2005","journal-title":"Nat. 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