MATERIALS AND RESULTS: Thirty-five paraffin-embedded ameloblastoma cases, ameloblastoma-derived cell lines (AM-1), and primary cultures of ameloblastoma stromal fibroblasts (ASF) were used. Immunohistochemistry, MTT assay, Western blotting, and RT-PCR were performed on these samples. Parenchyma-stromal CCN2 overexpression correlated significantly with fibrous-type stroma, but not with myxoid-type stroma, suggesting a role of CCN2 in fibrosis (P < 0.05). Recombinant CCN2 induction of enhanced ASF proliferation in AM-1 medium supports this view. Conversely, BMP4 and TGF-β were expressed in myxoid-type fibroblasts, but little expression was found in parenchyma. RANKL-positive and CD68-positive stromal cell populations were significantly greater in myxoid-type tumor areas than in fibrous-type tumor areas, while a higher Ki-67 labeling index was recorded in ameloblastoma with fibrous-type stroma. These data suggest that stromal properties influence bone resorption-related activities and growth rates, respectively.
CONCLUSIONS: These results suggest that the effects of secreted growth factors are governed by ameloblastoma parenchyma-stromal interactions. CCN2 promotes fibrogenesis independent of TGF-β signaling. Absence of CCN2 expression is associated with a phenotypic switch to a myxoid-type microenvironment that is conducive for TGF-β/BMP4 signaling to promote osteoclastogenesis.
METHODS: Hepatotoxicity was induced in adult female Wistar rats using carbon tetrachloride (CCl4 ). Thirty-six rats were randomly divided into six groups with six rats in each group: Group 1 (normal control group), Group 2 (received only CCl 4 ), Group 3 (CCl 4 +low dose BM-MSCs), Group 4 (CCl 4 +high dose BM-MSCs), Group 5 (CCl 4 + silymarin), Group 6 (CCl 4 +silymarin+high dose BM-MSCs). Thirty days after the treatment, blood samples were collected for hepatocyte growth factor estimation. The rats were then killed, bone marrow was extracted for chromosomal aberration assay. Liver tissue was processed for evaluating the DNA fragmentation assay, histopathology, and scanning electron microscopy study.
RESULTS: Combination treatment of silymarin and high dose BM-MSCs significantly (P
Materials and Methods: We examined RANKL expression in 39 patients (21 males, 18 females) by immunohistochemistry. Four patients (10%) were presented with tumor recurrence, eight patients (20%) were complicated with lung metastasis, and two patients (5%) were presented with both recurrence and lung metastasis. Positive RANKL expression was assessed according to a scoring system evaluating the percentage of the immunostained epithelial area and the staining intensity. The cumulative score was calculated to determine the final score value. Data were analyzed using PASW version 18.0 and independent t-test between nonrecurrence/recurrence groups, and nonlung metastasis/lung metastasis groups. Significance was set at P < 0.05.
Results: Thirty-two patients (82%) scored 3 in RANKL-staining percentage from whole stromal cell population (>75%), 6 patients scored 2, and 1 patient scored 1. Nine patients (23%) scored 3 in RANKL-staining intensity (most intense), 19 patients (48%) scored 2, and 11 patients (29%) scored 1. Twenty six patients (67%) had strong RANKL expression (total score of 5-6), 12 patients (31%) showed moderate score (3-4) whereas only 1 patient (2%) showed weak RANKL expression. Together, the mean value of RANKL-staining percentage was 2.79, intensity 1.95 and the total score 4.77. The mean RANKL-staining percentage between recurrence and nonrecurrence groups was statistically significant (P = 0.009). There was no significant difference in the mean staining intensity and total score between nonrecurrence and recurrence groups, and staining percentage staining intensity and a total cumulative score of RANKL expression between lung metastasis and nonlung metastasis groups.
Conclusion: RANKL expression is generally high in Stage III GCT and is a reliable prognostic marker in predicting the risk of local recurrence however not in lung metastasis.