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121.
Involvement of an autocrine stromal cell derived factor-1/CXCR4 system on the distant metastasis of human oral squamous cell carcinoma 总被引:10,自引:0,他引:10
Uchida D Onoue T Tomizuka Y Begum NM Miwa Y Yoshida H Sato M 《Molecular cancer research : MCR》2007,5(7):685-694
We have previously shown that a stromal cell-derived factor-1 (SDF-1; CXCL12)/CXCR4 system is involved in the establishment of lymph node metastasis, but not in that of distant metastasis, in oral squamous cell carcinoma (SCC). In this study, we investigated the role of the autocrine SDF-1/CXCR4 system, with a focus on distant metastasis in oral SCC cells. The immunohistochemical staining of SDF-1 and CXCR4 using primary oral SCCs and metastatic lymph nodes showed a significantly higher number of SDF-1-positive cases among the metastatic lymph nodes than among the primary oral SCCs, which was associated with a poor survival rate among those of the former group. The forced expression of SDF-1 in B88 cells, which exhibit functional CXCR4 and lymph node metastatic potential (i.e., the autocrine SDF-1/CXCR4 system), conferred enhanced cell motility and anchorage-independent growth potential onto the cells. Orthotopic inoculation of the transfectant into nude mice was associated with an increase in the number of metastatic lymph nodes and more aggressive metastatic foci in the lymph nodes. Furthermore, the SDF-1 transfectant (i.e., the autocrine SDF-1/CXCR4 system) exhibited dramatic metastasis to the lung after i.v. inoculation, whereas the mock transfectant (i.e., the paracrine SDF-1/CXCR4 system) did not. Under the present conditions, AMD3100, a CXCR4 antagonist, significantly inhibited the lung metastasis of the SDF-1 transfectant, ameliorated body weight loss, and improved the survival rate of tumor-bearing nude mice. These results suggested that, in cases of oral SCC, the paracrine SDF-1/CXCR4 system potentiates lymph node metastasis, but distant metastasis might require the autocrine SDF-1/CXCR4 system. 相似文献
122.
Taking advantage of the phenomenon of bioluminescence resonance energy transfer (BRET), we developed a bioluminescent probe composed of EYFP and Renilla reniformis luciferase (RLuc)--BRET-based autoilluminated fluorescent protein on EYFP (BAF-Y)--for near-real-time single-cell imaging. We show that BAF-Y exhibits enhanced RLuc luminescence intensity and appropriate subcellular distribution when it was fused to targeting-signal peptides or histone H2AX, thus allowing high spatial and temporal resolution microscopy of living cells. 相似文献
123.
Enoki N Kiyoshima T Sakai T Kobayashi I Takahashi K Terada Y Sakai H 《Journal of molecular histology》2007,38(4):321-332
This study investigated the age-dependent changes in the number of BrdU- and TUNEL-positive cells in murine gingival tissue
and submandibular gland, and compared the findings with those in other tissues and organs. The cell proliferative activity
was decreased after 20 weeks of age in epithelial cells of the gingiva, tongue, buccal mucosa and skin. A decreased cell proliferative
activity was also associated with aging in the liver and kidney parenchymal cells. Meanwhile, cell death showed peculiar changes
in gingival subepithelial tissue, and mucous and serous acini of the submandibular gland. An increase of TUNEL-positive cells
was demonstrated in gingival subepithelial tissue after 20-week-old of age. A significant increase of TUNEL-positive cells
was also found in the mucous acinar cells in the 20-week-old mice and in the serous acini after 20 weeks. The fluctuation
in the number of TUNEL-positive cells in the subepithelial tissue of the skin, and BrdU- and TUNEL-positive staining ratios
in the liver was smaller than that in other tissue and organs throughout life. This study may provide useful information for
better understanding the influence of aging on the functional alteration that occurs in the gingival tissue and submandibular
gland of the elderly. 相似文献
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127.
Jin‐Shu Yang Hiromichi Nagasawa Yoshihiro Fujiwara Shinji Tsuchida Wei‐Jun Yang 《Zoologica scripta》2010,39(6):621-630
Yang, J.‐S., Nagasawa, H., Fujiwara, Y., Tsuchida, S. & Yang, W.‐J. The complete mitogenome of the hydrothermal vent crab Gandalfus yunohana (Crustacea: Decapoda: Brachyura): a link between the Bythograeoidea and Xanthoidea. —Zoologica Scripta, 39, 621–630. Metazoan mitochondrial genomes (mitogenomes) are often used for all‐level phylogenetic analyses and evolution modelling. Although mitochondrial fragments facilitate studying the occurrence and dispersal of hydrothermal‐vent species, few complete mitogenomes have been determined for comprehensive analyses. We determined the complete nucleotide sequence of the bythograeid crab Gandalfus yunohana. The G. yunohana mitogenome is 15 567 bp in length and with an AT content of 69.9%. A putative control region of 625 bp was identified due to its position (between rrnS and trnI) and AT richness (72.8%), which exhibits high similarity with that of the Australian giant crab Pseudocarcinus gigas. The mitochondrial gene order is identical to the typical brachyuran mode. Codon usage, nucleotide composition and bias are well conserved as the Brachyura. Phylogenetic analyses from protein‐coding genes indicated its closest relationship with P. gigas. All the results support the close evolution distance between the Bythograeoidea and Xanthoidea, which might imply the possible origin that the only superfamily of vent crabs underwent. The G. yunohana mitogenome exhibits highly conserved characteristics with those of other decapods, especially its close relative brachyurans. A recent origin rather than the relic fauna was suggested. The present study will supply considerable data of use for both genomics and evolutionary research on hydrothermal vent ecosystems. 相似文献
128.
The induction of 2-amino-Delta(2)-thiazoline-4-carboxylic acid hydrolase (ATCase) and N-carbamoylcysteine amidohydrolase (NCCase), both of which are involved in the conversion step of 2-amino-Delta(2)-thiazoline carboxylic acid (ATC) to cysteine, was studied with Pseudomonas putida AJ3865. We found that L-ATC induced L-ATCase and L-NCCase, but that D-ATC induced only L-NCCase, whereas L- or D-NCC and thiazoline derivatives did not induce both enzymes. The bacterium showed neither D-ATCase nor D-NCCase activities, indicating that the role of L-ATC and D-ATC was different in the enzyme induction. We also found new inducers, d- and l-methionine, S-methyl-L-cysteine, cysteic acid, and 2-aminoethane sulfonic acid. However, the induction level of both enzymes by new inducers was much lower than those by L-ATC and D-ATC. Furthermore, the induction rate of both enzymes was synergistically increased only under a combination of D,L-ATC and new inducers. S-Compounds, however, such as new inducers except S-methyl-L-cysteine, inhibited both enzyme activities. This is the first report on the new inducers, synergistic induction, and the new inhibitors of L-ATCase and L-NCCase. 相似文献
129.
130.
Takami H Nakasone K Ogasawara N Hirama C Nakamura Y Masui N Fuji F Takaki Y Inoue A Horikoshi K 《Extremophiles : life under extreme conditions》1999,3(1):29-34
The nucleotide sequences of three independent fragments (designated no. 3, 4, and 9; each 15–20 kb in size) of the genome
of alkaliphilic Bacillus sp. C-125 cloned in a λ phage vector have been determined. Thirteen putative open reading frames (ORFs) were identified in
sequenced fragment no. 3 and 11 ORFs were identified in no. 4. Twenty ORFs were also identified in fragment no. 9. All putative
ORFs were analyzed in comparison with the BSORF database and non-redundant protein databases. The functions of 5 ORFs in fragment
no. 3 and 3 ORFs in fragment no. 4 were suggested by their significant similarities to known proteins in the database. Among
the 20 ORFs in fragment no. 9, the functions of 11 ORFs were similarly suggested. Most of the annotated ORFs in the DNA fragments
of the genome of alkaliphilic Bacillus sp. C-125 were conserved in the Bacillus subtilis genome. The organization of ORFs in the genome of strain C-125 was found to differ from the order of genes in the chromosome
of B. subtilis, although some gene clusters (ydh, yqi, yer, and yts) were conserved as operon units the same as in B. subtilis.
Received: April 17, 1998 / Accepted: June 23, 1998 相似文献