Table of Contents
Definition / general | Terminology | Pathophysiology | Clinical features | Uses by pathologists | Microscopic (histologic) images | Positive staining - normal | Positive staining - disease | Negative stainingCite this page: Pernick N. CD26. PathologyOutlines.com website. http://www.pathologyoutlines.com/topic/cdmarkerscd26.html. Accessed March 20th, 2019.
Definition / general
- Widely expressive dipeptidase with various clinical features (see below)
Terminology
- Also called dipeptidyl-peptidase IV, DPP4, DDPIV, adenosine deaminase complexing protein 2 (OMIM #102720)
Pathophysiology
- Costimulatory molecule in T cell activation and proliferation
- Also regulates various chemokines and cytokines
- Cleaves amino-terminal dipeptides
- Key role in cell adhesion and invasion (BMC Cancer 2013;13:517), plays a role in cell spreading and migration
- Either soluble in plasma or present on cell surface
Clinical features
- Acute kidney transplant rejection: associated with increased serum CD26, and CD26 inhibition reduces acute and accelerated rejection (Adv Exp Med Biol 2003;524:133)
- Colorectal carcinoma: marker of poor prognosis (PLoS One 2014;9:e98582, PLoS One 2014;9:e107470)
- Endometrial carcinoma: reduced expression (Am J Obstet Gynecol 2003;188:670)
- HIV infection: may have protective role (Virol J 2010;7:343)
- Lung: soluble CD26 in serum/pleural fluid may distinguish pleural mesothelioma (lower values) from pulmonary adenocarcinoma (PLoS One 2014;9:e115647)
- Lung: may function as tumor suppressor in non small cell lung carcinoma (Int J Cancer 2004;109:855)
- Lymphoma, T cell: absence of CD26 staining on peripheral blood CD4+ T cells by flow cytometry may be useful for diagnosis (Am J Clin Pathol 2001;115:885, but see Am J Clin Pathol 2008;129:146)
- Pregnancy: blastocyst implantation may occur by binding of endometrial CD26 to embryonal fibronectin (Mol Hum Reprod 2006;12:491)
- Prostate cancer: possible poor prognostic marker (J Res Med Sci 2013;18:647)
- Thyroid carcinoma: increased expression (Diagn Cytopathol 2002;26:366, Am J Clin Pathol 1991;96:306)
- In initial study, CD26high T cells elicit tumor immunity against multiple malignancies via enhanced migration and persistence (Nat Commun 2017;8:1961)
Uses by pathologists
- No significant uses at this time
Microscopic (histologic) images
Images hosted on other servers:
Colon: normal
Kidney: proximal tubules
Prostate: carcinoma
Positive staining - normal
- Activated T and B cells, basophils, macrophages, NK cells, thymocytes (mature)
- Epithelium: endometrium, hepatocytes, lung, prostate, renal proximal tubular cells, small intestine
- Also cytotrophoblast and extravillous trophoblast (J Clin Endocrinol Metab 2002;87:4287), biliary canaliculae, endothelial cells, fibroblasts, mesothelial cells (Oncology 2002;63:158), splenic sinus lining cells
Positive staining - disease
- Esophageal adenocarcinoma and Barrett's metaplasia (Hum Pathol 1999;30:1291)
- Prostate carcinoma, thyroid anaplastic carcinoma (reduced expression in undifferentiated vs. differentiated areas (Am J Clin Pathol 2006;125:399)
- Wilm's tumor (Hum Pathol 1990;21:536)
Negative staining
- Normal thyroid gland, T cells in peripheral blood of mycosis fungoides / cutaneous T cell lymphoma (40%, BMC Clin Pathol 2002;2:5)
