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Pancreatic cancer has a high mortality rate due to metastasis. Whereas KRAS is mutated in most pancreatic cancer patients, controlling KRAS or its downstream effectors has not been succeeded clinically. ARL4C is a small G protein whose expression is induced by the Wnt and EGF-RAS pathways. In the present study, we found that ARL4C is frequently overexpressed in pancreatic cancer patients and showed that its localization to invasive pseudopods is required for cancer cell invasion. IQGAP1 was identified as a novel interacting protein for ARL4C. ARL4C recruited IQGAP1 and its downstream effector, MMP14, to invasive pseudopods. Specific localization of ARL4C, IQGAP1, and MMP14 was the active site of invasion, which induced degradation of the extracellular matrix. Moreover, subcutaneously injected antisense oligonucleotide against ARL4C into tumor-bearing mice suppressed metastasis of pancreatic cancer. These results suggest that ARL4C-IQGAP1-MMP14 signaling is activated at invasive pseudopods of pancreatic cancer cells. [ABSTRACT FROM AUTHOR]

Characterization of mine waste rocks and prediction of acid mine drainage (AMD) play an important role in preventing AMD. Although high-tech analytical methods have been highlighted for mineral characterization and quantification, simple testing methods are still practical ways to perform in a field laboratory in mines. Thus, this study applied some simple testing methods to the characterization of mine wastes and AMD prediction in addition to a leaching test and the sequential extraction test with HCl, HF, and HNO3, which have not been applied for these purposes, focusing on the form of sulfur and the neutralization effects of carbonates. The results of the Acid Buffering Characteristic Curve test supported the changing trend of the pH attributing carbonates only during the first 10 leaching cycles in the leaching test. The change in the Net Acid Generating (NAG) pH in the sequential NAG test reflected the solubility of sulfur in the rocks, providing information on the form of sulfur in the rocks and the acid-producing potential over time. Consequently, the sequential NAG test and sequential extraction with the acids in combination with the current standards tests (Acid Base Accounting and NAG tests) provided important information for preventing AMD. [ABSTRACT FROM AUTHOR]

Epithelial tubular morphogenesis (tubulogenesis) is a fundamental morphogenetic process of many epithelial organs. In this developmental process, epithelial cells migrate, proliferate, polarize and differentiate towards surrounding mesenchymal tissue to form tubule structures. Although epithelial tissue structures are basically stable in the postnatal period, epithelial cells regain highly proliferative and invasive potentials within mesenchymal tissue during tumour formation (tumourigenesis). Therefore, there must be a common molecular basis orchestrating the cellular behaviours involved in both tubulogenesis and tumourigenesis. ADP-ribosylation factor (Arf)-like protein 4c (Arl4c), which belongs to the small GTP-binding protein family, is expressed by the simultaneous activation of Wnt--β-catenin and growth factor--Ras-mitogen-activated protein kinase signalling, was identified as an essential regulator of tubulogenesis. Arl4c expression was also involved in the tumour formation of colorectal and lung cancers. In this review, we focus on Arl4c as a novel Wnt signal target molecule that links epithelial tubulogenesis to tumourigenesis. [ABSTRACT FROM AUTHOR]

Prickle is known to be involved in planar cell polarity, including convergent extension and cell migration; however, the detailed mechanism by which Prickle regulates cellular functions is not well understood. Here, we show that Prickle1 regulates front-rear polarization and migration of gastric cancer MKN1 cells. Prickle1 preferentially accumulated at the cell retraction site in close proximity to paxillin at focal adhesions. Prickle1 dynamics correlated with those of paxillin during focal adhesion disassembly. Furthermore, Prickle1 was required for focal adhesion disassembly. CLASPs (of which there are two isoforms, CLASP1 and CLASP2, in mammals) and LL5β (also known as PHLDB2) have been reported to form a complex at cell edges and to control microtubule-dependent focal adhesion disassembly. Prickle1 was associated with CLASPs and LL5β, and was required for the LL5β-dependent accumulation of CLASPs at the cell edge. Knockdown of CLASPs and LL5β suppressed Prickle1- dependent cell polarization and migration. Prickle1 localized to the membrane through its farnesyl moiety, and the membrane localization was necessary for Prickle1 to regulate migration, to bind to CLASPs and LL5β, and to promote microtubule targeting of focal adhesions. Taken together, these results suggest that Prickle1 promotes focal adhesion disassembly during the retraction processes of cell polarization and migration. [ABSTRACT FROM AUTHOR]

Growth factor signaling is involved in the development of various organs, but how signaling regulates organ morphogenesis and differentiation in a coordinated manner remains to be clarified. Here, we show how WNT signaling controls epithelial morphogenetic changes and differentiation using the salivary gland as a model. Experiments using genetically manipulated mice and organ cultures revealed that WNT signaling at an early stage (E12-E15) of submandibular salivary gland (SMG) development inhibits end bud morphogenesis and differentiation into proacini by suppressing Kit expression through the upregulation of the transcription factor MYB, and concomitantly increasing the expression of distal progenitor markers. In addition, WNT signaling at the early stage of SMG development promoted end bud cell proliferation, leading to duct formation. WNT signaling reduction at a late stage (E16-E18) of SMG development promoted end bud maturation and suppressed duct formation. Thus, WNT signaling controls the timing of SMG organogenesis by keeping end bud cells in an undifferentiated bipotent state. [ABSTRACT FROM AUTHOR]

Aim. To gain an insight into the effect of HCV replication-associated interference with the IFN system on hepatic mRNA expression involved in IFN production. Methods. Relative mRNA expression of TLR3/RIG-I signaling genes involved in IFN-β production was correlated with positive- and negative-strand HCV RNAs in pretreatment liver tissues responsive and nonresponsive to peginterferon and ribavirin for chronic hepatitis C genotype 1. Treatment response was analyzed for per protocol population at weeks 12 (n = 45) and 24 (n = 40) and at 24 weeks after treatment (n = 38). Results. HCV replication had no relation to the expression of TLR3, RIG-I, TRIF, IPS-1, IRF3, and IFN-β mRNAs in responders. In striking contrast, positive- and/or negative-strand HCV showed positive correlations with TLR3, RIG-I, TRIF, IPS-1, and IRF3 mRNAs in week-12 nonresponders; with RIG-I, TRIF, IPS- 1, and IRF3 mRNAs in week-24 nonresponders; and with TLR3, RIG-I, and IRF3 mRNAs in posttreatment nonresponders. Thus mRNA expression of TLR3/RIG-I signaling genes was increased in relation to viral replication in nonresponders. Conclusions. The findings in IFN nonresponders may imply a host feedback response to severe impairment of the IFN system associated with HCV replication. [ABSTRACT FROM AUTHOR]

A 920-MHz high-resolution NMR spectrometer has been operating at the Tsukuba Magnet Laboratory (TML) since April 2002. It has proved its effectiveness by determining the 3-D structures of protein molecules. To accelerate studies in structural biology and solid-state NMR, a second high-field NMR magnet was developed and installed at TML. Although its basic design was the same as that of the first magnet, some improvements were made. For the innermost coil, a 16% Sn-bronze-Processed (Nb, Ti)3 Sn conductor was employed. The increase in the critical current density above that of a 15% Sn-bronze-Processed (Nb, Ti)3 Sn conductor made it possible to reduce the conductor size from 3.5 mm × 1.75 mm in the first magnet to 2.80 mm × 1.83 mm in the second. At the same operating current of the first magnet, the second magnet is expected to operate at 930 MHz. The liquid helium reservoir and the superfluid helium cooler, which were separated in the first system, were united in the same chamber in the new magnet. The latter magnet was energized up to 21.9 T without quenching in March 2004 and has operated in a persistent-mode at that field. It will be utilized mainly for solid-state NMR measurements. [ABSTRACT FROM AUTHOR]

Photo-responsive gel droplets having nano- or pico-L volume that showed photo-induced gel–sol transition were successfully developed, for which the inter-droplet mass transport and the subsequent enzymatic reactions in the interior of the gel droplets were photo-triggered. [ABSTRACT FROM AUTHOR]

Objectives: It can be difficult to differentiate diffuse malignant peritoneal mesothelioma (DMPM) from reactive mesothelial hyperplasia (RMH) or peritoneal dissemination of gynecologic malignancies, such as epithelial ovarian cancer (EOC), which cause a large amount of ascites. Detection of the homozygous deletion of p16/CDKN2A (p16 by fluorescence in situ hybridization (FISH) is an effective adjunct in the diagnosis of malignant pleural mesothelioma. The aim of this study was to investigate the ability of the p16 FISH assay to differentiate DMPM from RMH and EOC. Methods: p16 FISH was performed in 28 DMPMs (successful in 19), 30 RMHs, and 40 EOC cases. The cutoff values of p16 FISH were more than 10% for homozygous deletion and more than 40% for heterozygous deletion. Results: According to the above criteria, nine (47.4%) of 19 successful DMPM cases were homozygous deletion positive, and three (15.8%) of 19 were heterozygous deletion positive, whereas all RMH cases were negative for the p16 deletion. In all four major histologic subtypes of EOC, neither p16 homozygous nor heterozygous deletions were detected. To differentiate DMPM from RMH or EOC, the sensitivity of the p16 homozygous deletion was 32% (9/28), and the specificity was 100%. Conclusions: Our study suggests that p16 FISH analysis is useful in differentiating DMPM from RMH and EOC when homozygous deletion is detected. [ABSTRACT FROM AUTHOR]

Glypicans are members of the heparan sulfate proteoglycans (HSPGs) and are involved in various growth factor signaling mechanisms. Although HSPGs affect the β-catenin-dependent and -independent pathways of Wnt signaling, how they regulate distinct Wnt pathways is not clear. It has been suggested that the β-catenin-dependent pathway is initiated through receptor endocytosis in lipid raft microdomains and the independent pathway is activated through receptor endocytosis in non-lipid raft microdomains. Here, evidence is presented that glypican-4 (GPC4) is localized to both membrane microdomains and that the localization affects its ability to regulate distinct Wnt pathways. GPC4 bound to Wnt3a and Wnt5a, which activate the β-catenin-dependent and -independent pathways, respectively, and colocalized with Wnts on the cell surface. LRP6, one of Wnt3a coreceptors, was present in lipid raft microdomains, whereas Ror2, one of Wnt5a coreceptors, was localized to non-lipid raft microdomains. Expression of GPC4 enhanced the Wnt3adependent β-catenin pathway and the Wnt5a-dependent β-catenin-independent pathway, and knockdown of GPC4 suppressed both pathways. A GPC4 mutant that was localized to only non-lipid raft microdomains inhibited the β-catenin-dependent pathway but enhanced the β-catenin-independent pathway. These results suggest that GPC4 concentrates Wnt3a and Wnt5a to the vicinity of their specific receptors in different membrane microdomains, thereby regulating distinct Wnt signaling. [ABSTRACT FROM AUTHOR]

Cytoskeleton-associated protein 4 (CKAP4) is a palmitoylated type II transmembrane protein localized to the endoplasmic reticulum (ER). Here, we found that knockout (KO) of CKAP4 in HeLaS3 cells induces the alteration of mitochondrial structures and increases the number of ER–mitochondria contact sites. To understand the involvement of CKAP4 in mitochondrial functions, the binding proteins of CKAP4 were explored, enabling identification of the mitochondrial porin voltage-dependent anion-selective channel protein 2 (VDAC2), which is localized to the outer mitochondrial membrane. Palmitoylation at Cys100 of CKAP4 was required for the binding between CKAP4 and VDAC2. In CKAP4 KO cells, the binding of inositol trisphosphate receptor (IP3R) and VDAC2 was enhanced, the intramitochondrial Ca2+ concentration increased and the mitochondrial membrane potential decreased. In addition, CKAP4 KO decreased the oxidative consumption rate, in vitro cancer cell proliferation under low-glucose conditions and in vivo xenograft tumor formation. The phenotypes were not rescued by expression of a palmitoylation-deficient CKAP4 mutant. These results suggest that CKAP4 plays a role in maintaining mitochondrial functions through the binding to VDAC2 at ER–mitochondria contact sites and that palmitoylation is required for this novel function of CKAP4. [ABSTRACT FROM AUTHOR]

Recent development in the superconducting REBCO joints is an encouraging prospect for realizing an HTS magnet in persistent current mode operation. In our ongoing project, we are developing a cryocooled 1 T REBCO magnet system with joints to demonstrate the joint performance in an operating condition expected, for example, for an MRI. Preliminarily, the small test coils have been fabricated to verify the winding method. Additionally, we have designed and manufactured the new leads structures for feeding the conductor from the winding to the joints. [ABSTRACT FROM AUTHOR]

Mitochondria are important cellular organelles that function as control centers of the energy supply for highly proliferative cancer cells and regulate apoptosis after cancer chemotherapy. Cisplatin is one of the most important chemotherapeutic agents and a key drug in therapeutic regimens for a broad range of solid tumors. Cisplatin may directly interact with mitochondria, which can induce apoptosis. The direct interactions between cisplatin and mitochondria may account for our understanding of the clinical activity of cisplatin and development of resistance. However, the basis for the roles of mitochondria under treatment with chemotherapy is poorly understood. In this review, we present novel aspects regarding the unique characteristics of the mitochondrial genome in relation to the use of platinum-based chemotherapy and describe our recent work demonstrating the importance of the mitochondrial transcription factor A (mtTFA) expression in cancer cells. [ABSTRACT FROM AUTHOR]

Abstract Case report  We report a case of a nonfunctioning pancreatic endocrine tumor arising from intracranial ectopic pancreatic tissue. History  An 11-year-old girl was admitted to our hospital with a brain tumor. Hydrocephalus and brain malformation were apparent at birth. We first identified a mass-like lesion in the child’s brain at age 4 months. We monitored the lesion yearly by magnetic resonance imaging (MRI) until she reached age 11 years. Gadolinium-enhanced MRI showed the lesion to be a tumor, which was resected. Pathology  Examination of surgical specimens revealed a mature pancreatic tissue. We also identified monotonous neoplastic cells with round nuclei and positive immunoreactivity for synaptophysin, chromogranin A, and neurospecific enolase. However, these cells were negative for pancreatic endocrine markers. We diagnosed nonfunctioning pancreatic endocrine tumor arising from intracranial ectopic pancreatic tissue. Conclusion  Migrating pancreatic elements may have induced brain malformation during embryonic development and subsequently become malignant. [ABSTRACT FROM AUTHOR]