RESUMEN
Taste buds develop in different regions of the mammal oral cavity. Adult stem cells in various organs including the tongue papillae are marked by leucine-rich repeat-containing G protein-coupled receptor 5 (Lgr5) and its homolog, Lgr6. Recent studies have reported that adult taste stem/progenitor cells in circumvallate papilla (CVP) on the posterior tongue are Lgr5-positive. In this study, we confirm the Lgr5 expression pattern during CVP development. A previous study reported that mesenchymal Fgf10 is necessary for maintaining epithelial Lgr5-positive stem/progenitor cells. To confirm the interaction between Lgr5-positive CVP epithelium and mesenchymal factor FGF10, reverse recombination (180-degree) was performed after tongue epithelium detachment. FGF10 protein-soaked bead implantation was performed after reverse recombination to rescue CVP development. Moreover, we reduced mesenchymal Fgf10 by BIO and SU5402 treatment which disrupted CVP morphogenesis. This study suggests that the crosstalk between epithelial Lgr5 and mesenchymal Fgf10 plays a pivotal role in CVP epithelium invagination during mouse tongue CVP development by maintaining Lgr5-positive stem/progenitor cells.
RESUMEN
BACKGROUND/AIMS: The tumor-node-metastasis (TNM) staging is an useful system to assess the prognosis of any solid cancer. As new TNM staging classification of 7th stomach cancer was revised in 2009, we evaluated the prognostic predictability of the 7th International Union Against Cancer/American Joint Committee on Cancer (UICC/AJCC) TNM classification compared to 6th UICC/AJCC TNM classification in gastric cancer. METHODS: From January 2000 to December 2009, 5-year survival rates of 266 patients with gastric cancer were calculated by the 6th and 7th UICC/AJCC TNM classification. RESULTS: Using the 7th UICC/AJCC TNM classification, there was no significant difference in the 5-year cumulative survival rates (5 YSR) between stage IIA and IIB, IIB and IIIA, and IIIA and IIIB (70% vs. 71%, p=0.530; 71% vs. 80%, p=0.703; 80% vs. 75%, p=0.576, respectively) though significant differences of the survival rates were observed among stages of 6th edition. Using T stage of 7th edition, 5 YSR was not different between T2 and T3 (86% vs. 82%, p=0.655). Using N stage of 7th edition, 5 YSR were not different between N1 and N2, N3a and N3b (79% vs. 81%, p=0.506; 41% vs. 17%, p=0.895, respectively). CONCLUSIONS: The 7th UICC/AJCC TNM classification had poor prognostic predictability in gastric cancer compared to the 6th edition.
