Original Article Piwil2 expressed in various stages of cervical neoplasia is a potential complementary marker for p16INK4a
Gang He, Li Chen, Yin Ye, Yi Xiao, Keding Hua, David Jarjoura, Toru Nakano, Sanford H. Barsky, Rulong Shen, Jian-Xin Gao
Department of Pathology, Comprehensive Cancer Center, and Biostatistic Center, Ohio State University Medical Center, Columbus, OH 43210; Department of Molecular Cell Biology, Research Institute for Microbial Diseases, Osaka University, Osaka, Japan.
Received March 17, 2010; accepted March 22, 2010; available online March 25, 2010
Abstract: Generally, cancers may undergo the developmental stages of benign proliferation, precancer and invasive cancer. Identification of biomarkers that are expressed throughout the developmental stages will facilitate detection, prevention and therapy of cancer. Piwil2, a member of AGO/PIWI family of proteins, has been suggested to be associated with tumor development. Here we reported that piwil2 can be detected by immunohistochemistry (IHC) in various stages of human cervical squamous cell carcinomas and adenocarcinomas. Interestingly, piwil2 was also detected in some metaplastic epithelial cells as well as histologically “normal” appearing tissues adjacent to malignant lesions. While all the premalignant and malignant lesions expressed varying levels of piwil2, p16INK4a (p16), a surrogate indicator of high-risk human papillomavirus (HR-HPV) infection, was detected in only 84.62% of the specimens. In Papanicolaou (Pap) test, piwil2 was also detected in atypical glandular cells (AGC), low-grade (LSIL) and high-grade squamous intraepithelial lesions (HSIL), whereas p16 was not always concomitantly detected in the same specimens. The results suggest that piwil2 might play important roles throughout the process of cervical cancer development and have potential to be used as a complementary marker for p16INK4a. It is worth further study to improve the sensitivity and specificity of current screening methods for cervical cancers. (AJTR1003004).
Key words: Piwil2, Cervical cancer; p16, Field cancerization; Tumor development
Address all correspondence to: Jian-Xin Gao M.D., Ph.D. Department of Pathology Comprehensive Cancer Center Ohio State University Medical Center 129 Hamilton Hall 1645 Neil Avenue Columbus, OH, 43210 Phone: 614-247-2341 Fax: 614-292-7027 E-mail: Jian-Xin.Gao@osumc.edu