Laminins are the major cell-adhesive proteins in the basement membrane, consisting of three subunits termed ␣, ␤, and ␥. The putative binding site for integrins has been mapped to the G domain of the ␣ chain, although trimerization with ␤ and ␥ chains is necessary for the G domain to exert its integrin binding activity. The mechanism underlying the requirement of ␤ and ␥ chains in integrin binding by laminins remains poorly understood. Here, we show that the C-terminal region of the ␥ chain is involved in modulation of the integrin binding activity of laminins. We found that deletion of the C-terminal three but not two amino acids within the ␥1 chain completely abrogated the integrin binding activity of laminin-511. Furthermore, substitution of Gln for Glu-1607, the amino acid residue at the third position from the C terminus of the ␥1 chain, also abolished the integrin binding activity, underscoring the role of Glu-1607 in integrin binding by the laminin. We also found that the conserved Glu residue of the ␥2 chain is necessary for integrin binding by laminin-332, suggesting that the same mechanism operates in the modulation of the integrin binding activity of laminins containing either ␥1 or ␥2 chains. However, the peptide segment modeled after the C-terminal region of ␥1 chain was incapable of either binding to integrin or inhibiting integrin binding by laminin-511, making it unlikely that the Glu residue is directly recognized by integrin. These results, together, indicate a novel mechanism operating in ligand recognition by laminin binding integrins.Laminins are a family of glycoproteins present in the basement membrane (1-3). All laminins are large heterotrimeric glycoproteins composed of ␣, ␤, and ␥ chains that assemble into a cross-shaped structure. To date, five ␣ chains (␣1-␣5), three ␤ chains (␤1-␤3), and three ␥ chains (␥1-␥3) have been identified, combinations of which yield at least 15 isoforms with distinct subunit compositions (4). Laminins contribute to basement membrane architecture and influence cell adhesion, spreading, and migration through binding to their cell surface receptors, particularly the integrin family of cell adhesion receptors (5-9).Integrins play important roles in cell-matrix adhesion and signaling events regulating proliferation and differentiation of cells. Among the various integrin family members, ␣6␤1, ␣6␤4, ␣3␤1, and ␣7␤1 have been shown to be the major laminin receptors expressed in many cell types (10). Binding sites for these integrins have been mapped to the C-terminal globular (G) 3 domain of the laminin ␣ chains (6, 11-15). The G domain consists of five tandemly repeated LG modules of ϳ200 amino acid residues, designated LG1 through LG5. By analogy with the identification of the Arg-Gly-Asp (RGD) cell-adhesive motif in fibronectin, many attempts have been made to identify specific sequences mimicking the integrin binding activity of laminins. However, neither recombinant fragments of the G domain nor synthetic peptides modeled after the sequences in the G domain ...

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We found, using a BLAST search, a novel human gene (GenBank TM accession number BC029564) that possesses ␤3-glycosyltransferase motifs. The full-length open reading frame consists of 500 amino acids and encodes a typical type II membrane protein. This enzyme has a domain containing ␤1,3-glycosyltransferase motifs, which are widely conserved in the ␤1,3-galactosyltransferase and ␤1,3-N-acetylglucosaminyltransferase families. The putative catalytic domain was expressed in human embryonic kidney 293T cells as a soluble protein. Its N-acetylgalactosaminyltransferase activity was observed when N-acetylglucosamine (GlcNAc) ␤1-O-benzyl was used as an acceptor substrate. The enzyme product was determined to have a ␤1,3-linkage by NMR spectroscopic analysis, and was therefore named ␤1,3-Nacetylgalactosaminyltransferase-II (␤3GalNAc-T2). The acceptor substrate specificity of ␤3GalNAc-T2 was examined using various oligosaccharide substrates. Gal-␤1-3(GlcNAc␤1-6)GalNAc␣1-O-para-nitrophenyl (core 2-pNP) was the best acceptor substrate for ␤3GalNAc-T2, followed by GlcNAc␤1-4GlcNAc␤1-O-benzyl, and GlcNAc␤1-6GalNAc␣1-O-para-nitrophenyl (core 6-pNP), among the tested oligosaccharide substrates. Quantitative real time PCR analysis revealed that the ␤3Gal-NAc-T2 transcripts was restricted in its distribution mainly to the testis, adipose tissue, skeletal muscle, and ovary. Its putative orthologous gene, m␤3GalNAc-T2, was also found in a data base of mouse expressed sequence tags. In situ hybridization analysis with mouse testis showed that the transcripts are expressed in germ line cells. ␤3GalNAc-T2 efficiently transferred GalNAc to N-glycans of fetal calf fetuin, which was treated with neuraminidase and ␤-galactosidase. However, it showed no activity toward any glycolipid examined. Although the GalNAc␤1-3GlcNAc␤1-R structure has not been reported in humans or other mammals, we have discovered a novel human glycosyltransferase producing this structure on N-and O-glycans.

Gender identity disorder (GID) is a condition where an individual experiences significant gender dysphoria or discontent due to the divergence between their biological sex and their actually perceived sex. The concept of GID was introduced in the 20 th century [1], and the affected patients usually indicate an apparently normal somatic sexual differentiation and hope to live as the member of the opposite gender to their innate one. The number of patients diagnosed with the condition has been increasing in the past decade. Currently, a broad approach toward to treatment of GID is conducted from various aspects of law, sociology, psychol- Abstract. Gender identity disorder (GID) is a conflict between a person's actual physical gender and the one they identify him or herself with. Testosterone is the key agent in the medical treatment of female to male GID patients. We conducted a dose-response analysis of testosterone replacement therapy (TRT) in 138 patients to determine the onset of the therapeutic effects. The TRT consisted of intramuscular injection of testosterone enanthate and patients were divided into three groups; 250 mg every two weeks, 250 mg every three weeks and 125 mg every two weeks. The onset of deepening of voice, increase in facial hair and cessation of menses was evaluated in each group. At one month after the start of TRT, the onset of these physical changes was more prevalent in the group receiving the higher dose of testosterone, and there were dosedependent effects observed between the three treatment groups. On the other hand, at six months after the start of TRT, most of the patients had achieved treatment responses and there were no dose-dependent effects with regard to the percentage of patients with therapeutic effects. No significant side effects were observed in any of the treatment groups. We demonstrated that the early onset of the treatment effects of TRT is dose-dependent, but within six months of starting TRT, all three doses were highly effective. Current study provides useful information to determine the initial dose of TRT and to suggest possible changes that should be made in the continuous dosage for long term TRT.Key words: Gender identity disorder, Testosterone, Female to male, Dose response analysis, Estradiol ogy and medicine to effectively manage the disorder.The aim of the treatment for GID patients is to provide relief from the dichotomy between body habitus and sex identity by the induction of desired mental changes and maintenance of an acceptable physical state of the opposite sex. With regard to the history of the medical approach towards GID, surgical intervention was first conducted in 1907, and hormone therapy using testosterone replacement in female to male GID was started from 1935 after the discovery of testosterone [2]. Currently, the treatment for GID consists of psychotherapy, hormone replacement therapy and sex reassignment surgery. The therapeutic strategy is often determined, and therapies are started, by incorporating the patient's preferences or base...

OBJECTIVEThere remains a large discrepancy among surgeons in expectations of vestibular schwannoma (VS) growth. The anticipated growth rate of a VS and its potential clinical impact are important factors when deciding whether to observe the lesion over time or to intervene. Previous studies of VS natural growth remain limited, mostly confined to linear measurements, often without high-resolution, thin-sequence imaging. The present study comprehensively assessed natural tumor growth rates using volumetric measurements.METHODSBetween 2012 and 2018, 212 treatment-naïve patients diagnosed with a unilateral VS were evaluated. A total of 699 MR images were assessed, with a range of 2–11 MR images per patient. All MR images preceded any intervention, with patients subsequently being observed through completion of data analysis (36%) or treated with stereotactic radiosurgery (32%) or microsurgical resection (32%). To determine precise tumor volumes, the tumor area was outlined on every slice, and the products of the area and slice thickness were summed (99% of scans were ≤ 1-mm slice thickness). A multilevel model with random effects was used to assess the mean volume change over time. Each tumor was categorized as one of the following: growing (volume increase by more than 20% per year), fast growing (volume increase by more than 100% per year), stable (volume change between 20% decrease and 20% increase per year), and shrinking (volume decrease by more than 20% per year).RESULTSThe mean VS volumetric growth rate was 33.5% per year (95% CI 26.9%–40.5%, p < 0.001). When assessing the frequencies of individual tumor annual growth rates, 66% demonstrated growth (30% fast growing), 33% were stable, and 1% exhibited shrinking over an average interval of 25 months. Larger tumors were associated with increased absolute growth, but there was no relationship between tumor size and proportional growth rate. There was also no relationship between patient age and tumor growth rate.CONCLUSIONSThis study comprehensively assessed VS volumetric growth rates using high-resolution images and was conducted in a large and diverse patient sample. The majority of the tumors exhibited growth, with about one-third growing at a rate of 100% per year. These findings may contribute to a consensus understanding of tumor behavior and inform clinical decisions regarding whether to intervene or observe.

Stress-inducible transcription factors play a pivotal role in cellular adaptation to environment to maintain homeostasis and integrity of the genome. Activating transcription factor 3 (ATF3) is induced by a variety of stress and inflammatory conditions and is over-expressed in many kinds of cancer cells. However, molecular mechanisms underlying pleiotropic functions of ATF3 have remained elusive. Here we employed systems analysis to identify genome-wide targets of ATF3 that is either induced by an alkylating agent methyl methanesulfonate (MMS) or over-expressed in a prostate tumour cell line LNCaP. We show that stress-induced and cancer-associated ATF3 is recruited to 5,984 and 1,423 targets, respectively, in the human genome, 89% of which are common. Notably, ATF3 targets are highly enriched for not only ATF/CRE motifs but also binding sites of several other stress-inducible transcription factors indicating an extensive network of stress response factors in transcriptional regulation of target genes. Further analysis of effects of ATF3 knockdown on these targets revealed that stress-induced ATF3 regulates genes in metabolic pathways, cell cycle, apoptosis, cell adhesion, and signalling including insulin, p53, Wnt, and VEGF pathways. Cancer-associated ATF3 is involved in regulation of distinct sets of genes in processes such as calcium signalling, Wnt, p53 and diabetes pathways. Notably, stress-induced ATF3 binds to 40% of p53 targets and activates pro-apoptotic genes such as TNFRSF10B/DR5 and BBC3/PUMA. Cancer-associated ATF3, by contrast, represses these pro-apoptotic genes in addition to CDKN1A/p21. Taken together, our data reveal an extensive network of stress-inducible transcription factors and demonstrate that ATF3 has opposing, cell context-dependent effects on p53 target genes in DNA damage response and cancer development.

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The pseudokinase Trib1 functions as a myeloid oncogene that recruits the E3 ubiquitin ligase COP1 to C/EBPa and interacts with MEK1 to enhance ERK phosphorylation. Close genetic effect of Trib1 on Hoxa9 has been observed in myeloid leukemogenesis where Trib1 overexpression significantly accelerates Hoxa9-induced leukemia onset. However, the mechanism underlying how Trib1 functionally modulates Hoxa9 transcription activity is unclear. Herein, we provide evidence that Trib1 modulates Hoxa9-associated super-enhancers. ChIP-seq analysis identified increased histone H3K27Ac signals at super-enhancers of the Erg, Spns2, Rgl1, and Pik3cd loci, as well as increased mRNA expression of these genes. Modification of super-enhancer activity was mostly achieved via the degradation of C/EBPa p42 by Trib1, with a slight contribution from the MEK/ERK pathway. Silencing of Erg abrogated the growth advantage acquired by Trib1 overexpression, indicating that Erg is a critical downstream target of the Trib1/Hoxa9 axis. Moreover, treatment of acute myeloid leukemia (AML) cells with the BRD4 inhibitor JQ1 showed growth inhibition in a Trib1/Erg-dependent manner both in vitro and in vivo. Upregulation of ERG by TRIB1 was also observed in human AML cell lines, suggesting that Trib1 is a potential therapeutic target of Hoxa9-associated AML. Taken together, our study demonstrates a novel mechanism by which Trib1 modulates chromatin and Hoxa9-driven transcription in myeloid leukemogenesis.