title: Bmi-1 expression predicts prognosis in salivary adenoid cystic carcinoma and correlates with epithelial-mesenchymal transition-related factors.
abstract: Salivary adenoid cystic carcinoma (AdCC) is known for its high propensity to invade and metastasize. Bmi-1 acts as an oncogene by controlling cell cycle and self-renewal of adult stem cells, and its overexpression correlates with metastasis and poor prognosis in several cancers. Epithelial-mesenchymal transition (EMT) plays a central role in cancer metastasis. A key step in EMT is the down-regulation of E-cadherin that can be repressed by the transcriptional factors, such as Snail and Slug. In the present study, we investigated Bmi-1, Snail, Slug, and E-cadherin expression by immunohistochemistry in 102 patients with AdCC and analyzed statistically whether their expression correlated with clinicopathologic factors and prognosis. Reverse transcription-polymerase chain reaction was also performed in 22 tumor tissues and the adjacent noncancerous tissues to confirm Bmi-1 status in AdCCs. Our data demonstrated significant associations between the tumor metastasis and the expression of Bmi-1, Snail, Slug, and E-cadherin. Furthermore, a high level of Bmi-1 was not only correlated with the overexpression of Snail and Slug but also indicated an unfavorable metastasis-free survival and served as a high-risk marker for AdCC. In addition, Bmi-1 messenger RNA level was found much higher in AdCC tissues than in the adjacent noncancerous salivary gland tissues. Our results suggest that Bmi-1 may play a crucial role in AdCC progression by interaction with EMT-related markers and predict poor survival.
authors.affiliation: Department of Oral Pathology, Peking University School and Hospital of Stomatology, Beijing 100081, PR China.
authors.forename: Chun
authors.initials: C
authors.lastname: Yi
authors.affiliation: Department of Oral Pathology, Peking University School and Hospital of Stomatology, Beijing 100081, PR China.
authors.forename: Bin-Bin
authors.initials: BB
authors.lastname: Li
authors.affiliation: Department of Oral Pathology, Peking University School and Hospital of Stomatology, Beijing 100081, PR China. Electronic address: zhoucx2008@126.com.
authors.forename: Chuan-Xiang
authors.initials: CX
authors.lastname: Zhou
mesh_terms: D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism; D003528:Carcinoma, Adenoid Cystic / Q000175:diagnosis* / Q000378:metabolism*; D045744:Cell Line, Tumor; D058750:Epithelial-Mesenchymal Transition / Q000502:physiology*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods; D008297:Male; D008875:Middle Aged; D063150:Polycomb Repressive Complex 1 / Q000378:metabolism*; D011379:Prognosis; D012468:Salivary Gland Neoplasms / Q000175:diagnosis / Q000378:metabolism*; D014157:Transcription Factors / Q000378:metabolism
chemical_list: C069077:BMI1 protein, human; D014408:Biomarkers, Tumor; D014157:Transcription Factors; D063150:Polycomb Repressive Complex 1
keywords: Bmi-1; EMT; Metastasis; Salivary adenoid cystic carcinoma