Expression of the p73 protein in rectal cancers with or without preoperative radiotherapy
2006 (English)In: International Journal of Radiation Oncology, Biology, Physics, ISSN 0360-3016, Vol. 65, no 4, 1143-1148 p.Article in journal (Refereed) Published
Purpose: To investigate p73 expression in normal mucosa, primary tumor, and metastasis in relation to radiotherapy (RT) response and clinicopathologic/biologic variables in rectal cancers.
Methods and Materials: p73 was immunohistochemically examined on biopsies (unirradiated, n = 102), distant (from the large bowel, n = 82), and adjacent (adjacent to primary tumor, n = 89) normal mucosa samples, primary tumors (n = 131), and lymph node metastasis (n = 32) from rectal cancer patients participating in a clinical trial of preoperative RT. Seventy-four patients received surgery alone and 57 received additional RT.
Results: Cytoplasmic p73 was increased in the primary tumor compared with the distant or adjacent mucosa (p ≤ 0.0001). Nuclear (p = 0.02) and cytoplasmic (p = 0.003) p73 was higher in irradiated distant mucosa samples than in unirradiated ones, and nuclear p73 tended to be increased in irradiated primary tumors compared with unirradiated ones (p = 0.06). p73 was positively related to cyclooxygenase-2 expression in irradiated tumors (p = 0.03). p73-negative tumors tended to have a lower local recurrence after RT compared with unirradiated cases (p = 0.06).
Conclusions: Normal epithelial cells seem more sensitive to RT than tumor cells regarding p73 expression. Patients with p73-negative rectal tumors may have a lower risk of local recurrence after RT.
Place, publisher, year, edition, pages
Elsevier , 2006. Vol. 65, no 4, 1143-1148 p.
p73; Radiotherapy; Local recurrence; Rectal cancer; Immunohistochemistry
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-18430DOI: 10.1016/j.ijrobp.2006.02.028PubMedID: 16750334OAI: oai:DiVA.org:liu-18430DiVA: diva2:219161