AXIN1 mutations in hepatocellular carcinomas, and growth suppression in cancer cells by virus-mediated transfer of AXIN1.

The Wnt signaling pathway is essential for development and organogenesis. Wnt signaling stabilizes beta-catenin, which accumulates in the cytoplasm, binds to 1-cell factor (TCF; also known as lymphocyte enhancer-binding factor, LEF) and then upregulates downstream genes. Mutations in CTNNB1 (encoding beta-catenin) or APC (adenomatous polyposis coli) have been reported in human neoplasms including colon cancers and hepatocellular carcinomas (HCCs). Because HCC5 tend to show accumulation of beta-catenin more often than mutations in CTNNB1, we looked for mutations in AXIN1, encoding a key factor for Wnt signaling, in 6 HCC cell lines and 100 primary HCC5. Among the 4 cell lines and 87 HCC5 in which we did not detect CTNNB1 mutations, we identified AXIN1 mutations in 3 cell lines and 6 mutations in 5 of the primary HCCs. In cell lines containing mutations in either gene, we observed increased DNA binding of TCF associated with beta-catenin in nuclei. Adenovirus mediated gene transfer of wild-type AXINI induced apoptosis in hepatocellular and colorectal cancer cells that had accumulated beta-catenin as a consequence of either APC, CTNNB1 or AXIN1 mutation, suggesting that axin may be an effective therapeutic molecule for suppressing growth of hepatocellular and colorectal cancers.

Relationship between perceived softness of bilayered skin models and their mechanical properties measured with a dual-sensor probe.

The development of a sensor system that can predict the subjective softness of human skin is an important goal for the cosmetics industry. Here, we first carried out a subjective softness evaluation test using 65 skin models consisting of polyurethane bilayers with different thickness of the superficial layer and different degree of cross-polymerization of the basal layer. The results showed that perceived softness was dependent on the mechanical properties of both the superficial and basal layers. Then, we used a recently developed tactile sensor system composed of a piezoelectric tactile sensor and a load cell to measure mechanical softness parameters of the superficial layer and the whole model, respectively. Statistical analysis showed that the data obtained from these two sensors were well correlated with the perceived softness of the prepared models. These results suggest that it may be feasible to predict the subjective softness of human skin in vivo from non-invasive mechanical softness measurements of the superficial skin layer and whole skin obtained with our new dual-probe sensor system.

Effects of oxidative treatments on human hair keratin films.

The effects of hydrogen peroxide and commercial bleach on hair and human hair keratin films were examined by protein solubility, scanning electron microscopy (SEM), immunofluorescence microscopy, immunoblotting, and Fourier-transform infrared spectroscopy. Protein solubility in solutions containing urea decreased when the keratin films were treated with hydrogen peroxide or bleach. Oxidative treatments promoted the urea-dependent morphological change by turning films from opaque to transparent in appearance. Immunofluorescence microscopy and immunoblotting showed that the oxidation of amino acids and proteins occurred due to the oxidative treatments, and such occurrence was more evident in the bleach-treated films than in the hydrogen peroxide-treated films. Compared with hair samples, the formation of cysteic acid was more clearly observed in the keratin films after the oxidative treatments.

Sex difference in human fingertip recognition of micron-level randomness as unpleasant.

We investigated sex difference in evaluation, using the human fingertip, of the tactile impressions of three different micron-scale patterns laser-engraved on plastic plates. There were two ordered (periodical) patterns consisting of ripples on a scale of a few micrometres and one pseudo-random (non-periodical) pattern; these patterns were considered to mimic the surface geometry of healthy and damaged human hair, respectively. In the first experiment, 10 women and 10 men ran a fingertip over each surface and determined which of the three plates felt most unpleasant. All 10 female participants reported the random pattern, but not the ordered patterns, as unpleasant, whereas the majority of the male participants did not. In the second experiment, 9 of 10 female participants continued to report the pseudo-random pattern as unpleasant even after their fingertip had been coated with a collodion membrane. In the third experiment, participants were asked to evaluate the magnitude of the tactile impression for each pattern. The results again indicated that female participants tend to report a greater magnitude of unpleasantness than male participants. Our findings indicate that the female participants could readily detect microgeometric surface characteristics and that they evaluated the random pattern as more unpleasant. Possible physical and perceptual mechanisms involved are discussed.

Molecular cloning of a candidate tumor suppressor gene, DLC1, from chromosome 3p21.3.

The short arm of chromosome 3 is thought to contain multiple tumor suppressor genes, because one copy of this chromosomal arm frequently is missing in carcinomas that have arisen in a variety of tissues. We have isolated a novel gene encoding a 1755-amino acid polypeptide, through large-scale sequencing of genomic DNA at 3p21.3. Mutational analysis of this gene by reverse transcription-PCR revealed the lack of functional transcripts and an increase of nonfunctional RNA transcripts in a significant proportion (33%) of cancer cell lines and primary cancers (4 of 14 esophageal cancer cell lines, 2 of 2 renal cancer cell lines, 11 of 30 primary non-small cell lung cancers, and 3 of 10 primary squamous cell carcinomas of the esophagus). However, no alterations of the gene itself were detected in any of the cancers examined. Introduction of the cDNA significantly suppressed the growth of four different cancer cell lines, two of which produced no normal transcript on their own. No such effect occurred when antisense cDNA, cDNA corresponding to an aberrant transcript, or the vector DNA alone were transfected. These data suggest that aberrant transcription of this gene, designated DLC1 (deleted in lung cancer 1), may be involved in carcinogenesis of the lung, esophagus, and kidney.

Isolation and characterization of a novel human gene, DRCTNNB1A, the expression of which is down-regulated by beta-catenin.

Beta-catenin plays significant roles in cell-to-cell adhesion and the Wnt/Wg signal transduction pathway. Accumulation of this protein in the cytoplasm and nucleus as a result of mutations of the adenomatous polyposis coli tumor suppressor gene or of the beta-catenin gene itself is often seen in a wide variety of tumors including carcinomas of the colon, liver, uterus, and brain. Interaction of accumulated beta-catenin with Tcf/Lef transcription factors is known to deregulate expression of some downstream genes, but the precise mechanisms whereby beta-catenin contributes to carcinogenesis remain to be disclosed. Here we report isolation of a novel murine gene, Drctnnb1a (down-regulated by Ctnnb1, a), the expression of which was experimentally down-regulated in response to the activated form of beta-catenin. To investigate a possible role of DRCTNNB1A in cancers, we also isolated the human homologue, DRCTNNB1A, the deduced product of which was 91% identical to the murine protein. The transcript was expressed in all human tissues examined, and we assigned the genomic location of DRCTNNB1A to chromosomal band 7p15.3 by in situ hybridization. Expression of DRCTNNB1A in SW480 colon cancer cells was significantly increased in response to reduction of intracellular beta-catenin by adenovirus-mediated transfer of the beta-catenin-binding domain of the adenomatous polyposis coli gene into the cells. Furthermore, we documented reduced expression of DRCTNNB1A in 12 of 15 primary colorectal cancers examined, compared with corresponding adjacent noncancerous mucosae. Our results implied that DRCTNNB1A is one of the genes involved in the beta-catenin-Tcf/Lef signaling pathway, and that reduced expression of DRCTNNB1A may have some role in colorectal carcinogenesis.

Absence of genetic alteration at codon 531 of the human c-src gene in 479 advanced colorectal cancers from Japanese and Caucasian patients.

Activation of c-src, a cellular human gene homologous in sequence to the v-src gene of Rous sarcoma virus, had been thought to play an important role in the progression of several types of human cancers, without having undergone any genetic changes. However, recently truncating mutations at codon 531 of the c-src gene were reported in 12% of the advanced colon cancers, and it was also demonstrated that this change was activating, transforming, tumorigenic, and metastasis promoting. To investigate whether the codon 531-specific mutation could be involved in the carcinogenesis of colorectal cancer in the Japanese and Caucasian populations, we examined a total of 479 advanced colorectal cancers from 421 Japanese patients (46 of them with liver or lung metastases) and from 58 Caucasian patients (11 of them with liver metastases). Using the PCR-RFLP assay and additional single-strand conformation polymorphism analysis, we detected no genetic alteration in any of the advanced colorectal cancers. Our results suggest that the codon 531-specific mutational activation of c-src is unlikely to play a significant role in the malignant progression of colorectal cancers among most Japanese and Caucasian patients.

A novel "permanent" acid-type hair color made possible with dye-metal ion complex technology.

The advantages and disadvantages of oxidative permanent and acid-type semi-permanent hair colors are evident. The former provides a longlasting "permanent" color, while the latter imparts less damage to the hair. We developed a novel acid-type hair color technology that can allow an acid dye and a metal ion to form a complex inside the hair similar to the oxidative hair color. It is well known that acid dye diffuses into the hair and creates an ionic bond with the positively charged amino acid residues of hair protein. However, the dye can be extracted easily from the hair by daily shampooing due to the weakness of the bond. In order to strengthen this bond and to prevent the extraction of the dye by shampooing, an aluminum chloride ion was chosen as the metal ion component to form the dye-metal complex. A proper composition of penetration enhancers, benzyl alcohol and ethyl alcohol, was required to allow acid dyes to interact with the aluminum chloride ion after each component penetrates deeply into the hair to form a complex inside the hair. To provide color brightness and a color longevity effect to hair color, glycolic acid was also selected due to the observation that a weak acid with a small molecular weight would enhance those effects.

[Ruptured dissecting aneurysm of the vertebral artery concurrent with contralateral intracerebellar hemorrhage].

A case of a dissecting vertebral aneurysm concurrent with contralateral cerebellar hemorrhage is reported. A 69-year-old man was referred to our hospital for treatment of subarachnoid hemorrhage (SAH). On admission, CT scanning showed SAH and left cerebellar hematoma. Angiography was performed and it revealed a dissecting aneurysm of the right vertebral artery. Proximal clipping of the right vertebral dissecting artery was performed through right suboccipital craniotomy. During the operation, the cerebellar hemisphere gradually became firm, but the operation was finished without any complications. After the operation, the patient's consciousness level decreased from somnolence to semicomatose for a period of 2 hours 30 min. CT scanning showed the left cerebellar hematoma expanding. The cerebellar hematoma was evacuated immediately by midline suboccipital craniectomy, and the patient's consciousness level improved. In such a case, care must be taken to discover the cause of the expansion and to prevent concurrent hematoma during the operation. Through this case, discussion was held concerning the pitfalls of treatment of aneurysmal subarachnoid hemorrhage concurrent with intracerebral hematoma in the remote region.

[L-dopa effective parkinsonism appeared after shunt revision of the aqueductal stenosis: report of two cases].

We present a two cases of parkinsonism that appeared after shunt revision in obstructive hydrocephalus patients. Case 1 was a 59-year-old man and case 2 was a 32-year-old woman. Parkinsonism appeared in both cases after 3 or 4 shunt revisions within a period of three months. Treatment with bromocriptine, amantadine and L-dops had no effect, but the parkinsonism dramatically improved with administration of L-dopa. It was thought that repeated dilatation and collapse of the third ventricle in a short period of time might have caused concussion of the nigrostriatal pathway, resulting in reversible function loss of the nigrostriatal pathway.

Isolation and mutational analysis of a novel human cDNA, DEC1 (deleted in esophageal cancer 1), derived from the tumor suppressor locus in 9q32.

The long arm of chromosome 9 is thought to contain one or more putative tumor suppressor genes that are mutated in squamous cell carcinomas. This region shows frequent loss of heterozygosity (LOH) in carcinomas arising in several developmentally related tissues, including the esophagus, head and neck, lung, and urinary bladder. We previously delineated the commonly deleted region in a panel of esophageal squamous cell carcinomas to a approximately 200 kb genomic segment at 9q32. Here we report the isolation of a novel gene, DEC1 (deleted in esophageal cancer 1), from the target region. Mutational analysis of this gene by reverse-transcriptase polymerase chain reaction disclosed significantly reduced expression of DEC1 in 8 of 13 (62%) esophageal cancer cell lines and in 16 of 30 (53%) primary squamous cell carcinomas of the esophagus. However, no genetic alteration was detected in any of the cancers examined. Introduction of DEC1 cDNA into 3 cancer cell lines that lacked expression of DEC1 significantly suppressed cell growth, whereas antisense cDNA or the vector DNA alone did not. Given the reduced expression of the DEC1 gene in esophageal cancer, the high frequency of LOH at 9q32 in esophageal carcinomas, and the fact that the DEC1 cDNA can suppress growth of some cancer cells in vitro, we suggest that the DEC1 gene is a candidate tumor suppressor in 9q32. Genes Chromosomes Cancer 27:169-176, 2000.

Isolation and characterization of a human cDNA homologous to the Xenopus laevis XCAP-C gene belonging to the structural maintenance of chromosomes (SMC) family.

We have isolated a human cDNA encoding a protein of 1288 amino acids that shows 77% identity in amino acid sequence to XCAP-C, Xenopus chromosome-associated polypeptide-C, belonging to the family of structural maintenance of chromosomes (SMC), which is known to play a crucial role in the proper condensation and segregation of mitotic chromosomes. In particular, an almost 200-amino-acid domain in the N-terminal, including an NTP-binding motif and that in the C-terminal domain, including a DA-box, were well conserved and showed 95% identity between human and frog, indicating that these two domains are functionally very important. The transcript of this gene was expressed ubiquitously in various human tissues, but thymus, testis, and colon seemed to express this gene more abundantly. We also determined its chromosomal location at 3q26.1 by fluorescence in situ hybridization.

Isolation of a novel human gene, ARHGAP9, encoding a rho-GTPase activating protein.

Members of the Rho family of small guanosine triphosphatases (Rho-GTPases) have emerged as key coordinators of signaling pathways leading to remodeling of the actin cytoskeleton, a process that plays a critical role in cell adhesion and migration. However, the precise regulatory mechanisms remain to be elucidated. Here we report isolation of a novel human gene, ARHGAP9, which encodes a protein containing a Rho-GTPase activating protein (Rho-GAP) domain, a src-homology 3 (SH3) domain, a pleckstrin homology (PH) region, and a WW domain. In vitro, the recombinant protein revealed substantial GAP activity toward Cdc42Hs and Rac1, and less toward RhoA. The transcript was predominantly expressed in peripheral blood leukocytes, spleen, and thymus. Exogenous expression of the entire coding region of ARHGAP9 into human leukemia KG-1 cells repressed adhesion of the cells to fibronectin and collagen IV. Our results indicate that ARHGAP9 is involved in regulating adhesion of hematopoietic cells to extracellular matrix.

Isolation and characterization of human NBL4, a gene involved in the beta-catenin/tcf signaling pathway.

beta-Catenin, a key regulator of cellular proliferation, is often mutated in various types of human cancer. To investigate cellular responses related to the beta-catenin signaling pathway, we applied a differential display method using mouse cells transfected with an activated form of mutant beta-catenin. This analysis and subsequent northern-blot hybridization confirmed that expression of a murine gene encoding NBL4 (novel band 4.1-like protein 4) was up-regulated by activation of beta-catenin. To examine a possible role of NBL4 in cancer, we isolated the human homologue of the murine NBL4 gene by matching mNBL4 against the human EST (expressed sequence tag) database followed by 5' rapid amplification of cDNA ends (5'RACE). The cDNA of hNBL4 encoded a protein of 598 amino acids that shared 87% identity in amino acid sequence with murine NBL4 and 71% with zebrafish NBL4. A 2.2-kb hNBL4 transcript was expressed in all human tissues examined with high levels of expression in brain, liver, thymus and peripheral blood leukocytes and low levels of expression in heart, kidney, testis and colon. We determined its chromosomal localization at 5q22 by fluorescence in situ hybridization. Expression of hNBL4 was significantly reduced when beta-catenin was depleted in SW480 cells, a human cancer cell line that constitutionally accumulates beta-catenin. The results support the view that NBL4 is an important component of the beta-catenin / Tcf pathway and is probably related to determination of cell polarity or proliferation.