Expression of Stem Cell Marker ALDH1 in Cervical Intraepithelial Neoplasia
Ping Gong, Juan Palazzo. Thomas Jefferson University Hospital, Philadelphia, PA
Background: Cervical cancer is the second most common type of cancer in women worldwide. The human papilloma virus (HPV) has recently been shown to specifically target cervical cancer stem cell (CSC) s. The ability to identify and characterize CSCs is crucial for understanding cervical cancer. Aldehyde degydrogenase (ALDH) 1, a detoxifying enzyme responsible for the oxidation of intracellular aldehydes, has been shown to be a stem cell marker in several tissue types and tumors. We investigated the expression pattern of ALDH1 in cervical intraepithelial neoplasia (CIN) and its possible role in carcinogenesis.
Design: Fifty-six cervical biopsy specimens with the diagnoses of normal cervical mucosa, koilocytosis, CIN1, CIN2, and CIN3 were collected from the pathology files at Thomas Jefferson University Hospital. All diagnoses were confirmed by at least two experienced pathologists. Immunohistochemical staining for ALDH1 was performed following a previously published protocol. Any cytoplasmic staining of ALDH1 in the epithelial cells was considered positive. Positive and negative controls were used in each study.
Results: Normal cervical mucosa had no ALDH1 expression. In koilocytosis, 2 of 7 cases showed ALDH1+ cells limited to the basal layer. In CIN1, 11 of 20 cases showed ALDH1+ cells limited to the lower 1/3 of epithelium and the other 9 cases were negative for ALDH1. In CIN2, 7 of the 13 cases showed positive cells limited to the basal layer, 4 cases showed positive cells extending to the mid and upper 1/3 of the mucosa. Two cases were negative for ALDH1. All CIN3/carcinoma in situ (CIS) cases were positive for ALDH1. Three of 6 cases show positive cells extending up to mid 1/3 of mucosa and the other three cases show positive cells extending up to the upper 1/3 of mucosa.
Conclusions: Cervical dysplasias show positive staining for ALDH1 compared to normal cervical mucosa. ALDH1 expression and distribution parallels the degree of cervical dysplasia. CSCs, as detected by ALDH1 expression, may play a role in the progression of cervical intraepithelial neoplasia and carcinogenesis.
Category: Gynecologic & Obstetrics
Tuesday, March 20, 2012 1:00 PM
Poster Session IV # 120, Tuesday Afternoon