TY - JOUR AU - Chiu, Hui-Fang AU - Yang, Chang-Shyue AU - Chi, Hsien-I AU - Han, Yi-Chun AU - Shen, You-Cheng AU - Venkatakrishnan, Kamesh AU - Wang, Chin-Kun PY - 2017/03/07 Y2 - 2024/03/29 TI - Cyclooxygenase-2 expression in oral precancerous and cancerous conditions and its inhibition by caffeic acid phenyl ester-enriched propolis in human oral epidermal carcinoma KB cells JF - Archives of Biological Sciences JA - Arch Biol Sci VL - 69 IS - 1 SE - Articles DO - UR - https://www.serbiosoc.org.rs/arch/index.php/abs/article/view/377 SP - 83-91 AB - <p>Oral cancer accounts for 3-5% of all cancers worldwide. The present study was undertaken to investigate the correlation between overexpression of cyclooxygenase-2 (COX-2) and various grades of oral cancer, and to ascertain the inhibitory effect of propolis in the human oral carcinoma cell line. For <em>ex vivo </em>studies, 45 patients with oral submucous fibrosis (OSF; n=15), oral leukoplakia (OLP; n=18) and oral squamous cell carcinoma (OSCC; n=18) were recruited, and a biopsy was done to determine COX-2 protein expression by Western blotting and immunohistochemistry (IHC). For the <em>in vitro</em> study, COX-2 levels were measured in human oral epidermal carcinoma cell line by immune blotting and IHC. The results of <em>ex vivo</em> studies by Western blotting revealed that COX-2 protein levels were highly upregulated in OSCC tissue, followed by OLP and OSF. The levels of COX-2 expression also showed a positive correlation with the grade (severity) of each oral precancerous and cancerous condition. Immunohistochemistry analysis revealed the presence of intense COX-2 staining in the cells of OSCC tissue, equivalent to the OLP and OSF specimens. In the <em>in vitro</em> study of oral carcinoma KB cells, Western blotting and IHC analysis showed that caffeic acid phenyl ester (CAPE)-rich propolis and celecoxib, a standard COX-2 inhibitor, markedly downregulated COX-2 expression. These results suggest that propolis exhibits a chemopreventive potential by lowering COX-2 expression in the oral carcinoma KB cell line. Hence, propolis might be used as an adjuvant therapy for treating oral cancer with standard chemotherapy drugs.</p><p><strong>DOI:</strong> <a href="http://doiserbia.nb.rs/Article.aspx?id=0354-46641600081C" target="_blank">10.2298/ABS160324081C</a></p><p><strong>Received:</strong> March 24, 2016; <strong>Revised:</strong> May 23, 2016; <strong>Accepted:</strong> May 24, 2016; <strong>Published online:</strong> September 19, 2016</p><p><strong>How to cite this article:</strong> Venkatakrishnan K, Wang CK. Cyclooxygenase-2 expression in oral precancerous and cancerous conditions and its inhibition by caffeic acid phenyl ester-enriched propolis in human oral epidermal carcinoma KB cells. Arch Biol Sci. 2017;69(1):83-91.</p> ER -