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The present study was directed towards the identification of novel factors involved in the transformation process leading to the formation of gastric cancer. A cDNA library from human gastric cancer cells was constructed using a retroviral vector. Functional cloning was performed by screening for transformation activity in transduced NIH3T3 cells. Six cDNA clones were isolated, including one encoding the elongation factor 1α α α α subunit, which was already known to play a role in tumorigenesis. One cDNA (clone 56.2), which was repeatedly isolated during the course of screening, encoded a protein identical to a G-protein-coupled receptor protein, GPR35. In addition, another cDNA clone (72.3) was found to be an alternatively spliced product of the GPR35 gene, whereby 31 amino acids were added to the N-terminus of GPR35. Hence, the proteins encoded by clones 56.2 and 72.3 were designated GPR35a and GPR35b, respectively. RT-PCR experiments revealed that GPR35 gene expression is low or absent in surrounding non-cancerous regions, while both mRNAs were present in all of the gastric cancers examined. The level of 72.3-encoded mRNA was consistently significantly higher than that of 56.2 encoded mRNA. An expression pattern similar to that observed in gastric cancers was detected in normal intestinal mucosa. Based on the apparent transformation activities of the two GPR35 clones in NIH3T3 cells, and the marked up-regulation of their expression levels in cancer tissues, it is speculated that these two novel isoforms of GPR35 are involved in the course of gastric cancer formation. (Cancer Science 2004; 95: 131-135)

, however, is regarded to be the key factor that prevents the rehydrogenation of dodecaborates.12 In order to elucidate the mechanism as well as to provide effective solutions to this problem, a novel solvent-free synthesis route of anhydrous M 2/n B 12 H 12 (here M means Li, Na, and K) has been developed. 13 Thermal stability and transformations of the anhydrous single phase Li 2 B 12 H 12 suggested the formation of the high temperature polymorph of Li 2 B 12 H 12 during the dehydrogenation of LiBH 4 , while concurrently emphasized the importance of further investigation on the decomposition mechanism of metal borohydrides and metal dodecaborates.14 The high stability of icosahedral [B 12 H 12 ] 2− , on the other hand, favors its potential application as solid electrolyte. Recently, Na + conductivity of Na 2 B 12 H 12 was reported to be 0.1 S/cm above its order−disorder phase transition at ∼529 K, 3 which is comparable to that of a polycrystalline β″-Al 2 O 3 (0.24 S/cm at 573 K) solid state Na-electrolyte. 15 Mechanistic understanding on the diffusion behavior of cation and further improvement of ionic conductivity at a lower temperature, however, are important in order to facilitate the practical application of metal dodecaborates as superionic conductors.Bimetallic compounds composed of two different metal elements often show different crystal structures and interesting chemical and physical properties, which are often distinguished from those of the monometallic counterparts. For example, bimetallic borohydrides have been proven as a way to tune the thermodynamics of metal borohydride decomposition.16−18 To our best knowledge, there has been no report of improving the ionic conductivity of M 2/n B 12 H 12 by introducing another metal to form a bimetallic dodecaborate, and we hypothesized that the coexistence of bimetallic elements could have a synergetic effect on the mobility change of each ion. LiNaB 12 H 12 was prepared through sintering of LiBH 4 , NaBH 4 , and B 10 H 14 with a stoichiometric molar ratio of 1:1:1. The successful synthesis was confirmed by X-ray diffraction, Raman spectra, and solid state nuclear magnetic resonance (NMR) measurements (see Supporting Information Figure S1).

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