title: Overexpression of CD26/DPPIV in mesothelioma tissue and mesothelioma             cell lines.
abstract: Mesothelioma, a highly aggressive cancer with poor prognosis and refractory             to currently available therapies show increasing trends of its incidence in Japan             and other developing countries. Although surgery is a gold standard for patients             with early mesothelioma, most patients with advanced disease are not suitable             for surgical resection and have option of palliative chemotherapy alone. One of             the new treatment strategies for mesothelioma, the humanized anti-CD26 monoclonal             antibody therapy is under development. CD26, a 110-kDa transmembrane glycoprotein             with known dipeptidyl peptidase IV activity, plays a role in tumor development             and its expression was reported in various human malignancies. This study determined             the preliminary selection criteria for humanized monoclonal anti-CD26 antibody             therapy. Eighty-one epithelioid (49 differentiated and 32 less differentiated),             34 sarcomatoid, 19 biphasic mesothelioma and 8 mesothelioma cell lines were immunohistochemically             examined using 8 different commercially available anti-CD26 antibodies for membranous             and cytoplasmic expression. The cytoplasmic expression of CD26 was observed in             all histological types of mesothelioma, while the membranous expression of CD26             was found in 88% of differentiated and 69% of less differentiated epithelioid             mesothelioma, and none of sarcomatoid mesothelioma with anti-CD26 antibodies with             rabbit polyclonal anti-DPP4 antibody and similar results were also obtained with             goat polyclonal anti-DPP4/CD26 antibody. These antibodies absorbed with soluble             human CD26 proteins do not show CD26 expression in mesothelioma tissue, suggesting             these two antibodies localize true CD26 protein. Seven mesothelioma cell lines,             including sarcomatoid types, also showed membranous expression of CD26 in cellblock             preparation. CD26 vector transfection to CD26-negative MSTO-211H cells showed             membranous expression of CD26 by flow cytometry, but not in tumor developed in             NOD/SCID mice with inoculation of CD26 vector transfected MSTO-211H cells. We             found that both rabbit and goat polyclonal antibodies are suitable for immunohistochemical             evaluation of membranous expression of CD26 in mesothelioma.
authors: Department of Pathology, Graduate School of Biomedical Sciences, Hiroshima University, 1-2-3 Kasumi, Minami-ku, Hiroshima, 734-8551, Japan. amatya@hiroshima-u.ac.jp
authors: Vishwa Jeet
authors: VJ
authors: Amatya
authors: Yukio
authors: Y
authors: Takeshima
authors: Kei
authors: K
authors: Kushitani
authors: Taketo
authors: T
authors: Yamada
authors: Chikao
authors: C
authors: Morimoto
authors: Kouki
authors: K
authors: Inai
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D061067:Antibodies, Monoclonal, Humanized / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000627:therapeutic use; D045744:Cell Line, Tumor; D002462:Cell Membrane / Q000378:metabolism*; D018819:Dipeptidyl Peptidase 4 / Q000235:genetics / Q000378:metabolism*; D005260:Female; D015870:Gene Expression; D006801:Humans; D008297:Male; D008654:Mesothelioma / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D016513:Mice, SCID; D008875:Middle Aged; D009368:Neoplasm Transplantation; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D055815:Young Adult
chemical_list: D061067:Antibodies, Monoclonal, Humanized; D000970:Antineoplastic Agents; D011994:Recombinant Proteins; C042807:DPP4 protein, human; D018819:Dipeptidyl Peptidase 4