The Apoptotic Effect of the Hexane Extract of Rheum undulatum L. in Oral Cancer Cells through the Down-regulation of Specificity Protein 1 and Survivin / 한국실험동물학회지

The hexane extract of Rheum undulatum L. (HERL) has been shown to have anti-cancer activity in several cancers in vivo and in vitro. However, the anti-cancer activity of HERL and its molecular mechanism in human oral cancer cells has not been explored. Thus, the aim of this study was to elucidate the growth-inhibitory and apoptosis-inducing effects of HERL in HN22 and SCC15 oral cancer cell lines. This study shows that HERL inhibits oral cancer growth, decreases cell viability, and causes apoptotic cell death in HN22 and SCC15 cells, as characterized by morphological changes, nuclear condensation and fragmentation, the cleavage of PARP and the accumulation of cells in the sub-G1 phase. The treatment of oral cancer cells with HERL also resulted in decreased expression of specificity protein (Sp1) and its downstream protein, survivin. Therefore, our results suggest that the regulation of Sp1 and survivin plays a critical role in HERL-induced apoptosis in human oral cancer cells.

Hexane-Soluble Fraction of the Common Fig, Ficus carica, Inhibits Osteoclast Differentiation in Murine Bone Marrow-Derived Macrophages and RAW 264.7 Cells

Osteoclasts, derived from multipotent myeloid progenitor cells, play homeostatic roles in skeletal modeling and remodeling, but may also destroy bone in pathological conditions such as osteoporosis and rheumatoid arthritis. Osteoclast development depends critically on a differentiation factor, the receptor activator of NF-kappaB ligand (RANKL). In this study, we found that the hexane soluble fraction of the common fig Ficus carica (HF6-FC) is a potent inhibitor of osteoclastogenesis in RANKL-stimulated RAW264.7 cells and in bone marrow-derived macrophages (BMMs). HF6-FC exerts its inhibitory effects by suppression of p38 and NF-kappaB but activation of ERK. In addition, HF6-FC significantly decreased the expression of NFATc1 and c-Fos, the master regulator of osteoclast differentiation. The data indicate that components of HF6-FC may have therapeutic effects on bone-destructive processes such as osteoporosis, rheumatoid arthritis, and periodontal bone resorption.

Fusion of the PLAG1 and CTNNB1 genes in pleomorphic adenoma of the salivary glands

The pleomorphic adenoma is the most common neoplasm involving both the major and minor salivary glands. It is a benign, slowgrowing tumor, but local recurrences can occur. The pleomorphic adenoma gene 1 (PLAG1), which is a novel zinc finger gene, is frequently activated by reciprocal chromosomal translocations involving 8q12 in a subset of salivary gland pleomorphic adenomas. This experimental study was preformed to observe the translocation patterns between PLAG1 gene and the three translocation partner genes. We also have analyzed the presence of PLAG1 transcripts by RT-PCR. CTNNB1/PLAG1 gene fusion was observed in three of nine pleomorphic adnomas. However, LIFR/PLAG1 and SII/PLAG1 gene fusions were not detectable. All of three gene fusions was not detectable in one Warthin's tumor and three inflammatory salivary gland tissues. PLAG1 transcripts were expressed in all inflammatory salivary gland tissues and tumors except for three pleomorphic adenomas. Of particular one pleomorphic adenoma showing CTNNB1/P AG1 gene fusion did not express PLAG1 transcipt. Our data indicate that gene fusion involving PLAG1 is a frequent event in pleomorphic adenoma, but correlation between gene fusion involving PLAG1 and PLAG1 transcription is not definite.