ABSTRACT
Abstract Multicystic and unicystic ameloblastomas are benign odontogenic tumors that present distinct biological behavior. The investigation of stem cells has become an important branch of tumor biology, with several studies addressing the possible role of these cells in tumor growth, angiogenesis, progression, infiltration and invasiveness. This study evaluated the immunohistochemical expression of CD90(Thy-1) and P75NTR stem cell markers in multicystic and unicystic ameloblastomas. Seventeen (17) samples of ameloblastomas (multicystic, n = 10; unicystic, n = 7) were submitted to immunohistochemical reactions and graded semi-quantitatively. The Kolmogorov-Smirnov test was used to verify possible differences in CD90 and P75NTR expressions between multicystic and unicystic ameloblastomas (p < 0.05). CD90 immunostaining was observed in all multicystic ameloblastoma specimens (n = 10), in the cytoplasm of the fibroblasts and vascular endothelial cells of the tumor stroma, near the neoplastic odontogenic epithelia. The staining of stromal CD90 was significantly higher in multicystic than in unicystic ameloblastomas (p = 0.003). Nuclear P75NTR immunostaining was observed in all ameloblastoma specimens. A significant difference was seen in the epithelial staining of P75NTR between multicystic and unicystic types (p = 0.007). The increased expression of CD90 and P75NTR found in multicystic ameloblastomas suggests a behavioral biological difference between multicystic and unicystic ameloblastomas, as well as a difference in ameloblastoma development.
Subject(s)
Humans , Male , Female , Adolescent , Adult , Young Adult , Neoplastic Stem Cells/metabolism , Ameloblastoma/metabolism , Mandibular Neoplasms/metabolism , Biomarkers, Tumor/metabolism , Receptors, Nerve Growth Factor/metabolism , Thy-1 Antigens/metabolism , Nerve Tissue Proteins/metabolism , Neoplastic Stem Cells/pathology , Immunohistochemistry , Ameloblastoma/pathology , Mandibular Neoplasms/pathology , Paraffin Embedding , Stromal Cells , Statistics, Nonparametric , Endothelial Cells/metabolism , Fibroblasts/metabolism , Middle AgedABSTRACT
PURPOSE: This study examined a rapid isolation method decreasing the time and cost of the clinical application of adipose tissue-derived stem cells (ASCs). MATERIALS AND METHODS: Aliquots (10 g) of the lipoaspirates were stored at 4degrees C without supplying oxygen or nutrients. At the indicated time points, the yield of mononuclear cells was evaluated and the stem cell population was counted by colony forming unit-fibroblast assays. Cell surface markers, stem cell-related transcription factors, and differentiation potentials of ASCs were analyzed. RESULTS: When the lipoaspirates were stored at 4degrees C, the total yield of mononuclear cells decreased, but the stem cell population was enriched. These ASCs expressed CD44, CD73, CD90, CD105, and HLA-ABC but not CD14, CD31, CD34, CD45, CD117, CD133, and HLA-DR. The number of ASCs increased 1x1014 fold for 120 days. ASCs differentiated into osteoblasts, adipocytes, muscle cells, or neuronal cells. CONCLUSION: ASCs isolated from lipoaspirates and stored for 24 hours at 4degrees C have similar properties to ASCs isolated from fresh lipoaspirates. Our results suggest that ASCs can be isolated with high frequency by optimal storage at 4degrees C for 24 hours, and those ASCs are highly proliferative and multipotent, similar to ASCs isolated from fresh lipoaspirates. These ASCs can be useful for clinical application because they are time- and cost-efficient, and these cells maintain their stemness for a long time, like ASCs isolated from fresh lipoaspirates.