The brain hypothalamus contains certain secreted molecules that are important in regulating feeding behaviour. Here we show that nesfatin, corresponding to NEFA/nucleobindin2 (NUCB2), a secreted protein of unknown function, is expressed in the appetite-control hypothalamic nuclei in rats. Intracerebroventricular (i.c.v.) injection of NUCB2 reduces feeding. Rat cerebrospinal fluid contains nesfatin-1, an amino-terminal fragment derived from NUCB2, and its expression is decreased in the hypothalamic paraventricular nucleus under starved conditions. I.c.v. injection of nesfatin-1 decreases food intake in a dose-dependent manner, whereas injection of an antibody neutralizing nesfatin-1 stimulates appetite. In contrast, i.c.v. injection of other possible fragments processed from NUCB2 does not promote satiety, and conversion of NUCB2 to nesfatin-1 is necessary to induce feeding suppression. Chronic i.c.v. injection of nesfatin-1 reduces body weight, whereas rats gain body weight after chronic i.c.v. injection of antisense morpholino oligonucleotide against the gene encoding NUCB2. Nesfatin-1-induced anorexia occurs in Zucker rats with a leptin receptor mutation, and an anti-nesfatin-1 antibody does not block leptin-induced anorexia. In contrast, central injection of alpha-melanocyte-stimulating hormone elevates NUCB2 gene expression in the paraventricular nucleus, and satiety by nesfatin-1 is abolished by an antagonist of the melanocortin-3/4 receptor. We identify nesfatin-1 as a satiety molecule that is associated with melanocortin signalling in the hypothalamus.

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Early hepatocellular carcinoma (HCC) has been defined as a well-differentiated cancer containing Glisson's triad, but it remains unknown whether this lesion is curable. We prospectively studied 70 patients (enrolled from 1,172 referrals between 1982 and 1991) who had a diagnosis of a single HCC 2 cm or less in diameter (Stage T1) and who underwent curative hepatectomy and long-term follow-up (range, 0.2 to 14.3 years). Patients were eligible for surgery if they had a tumor that met the diagnostic criteria for HCC and were in Child-Pugh class A (n ‫؍‬ 59) or B (n ‫؍‬ 11) status. Among the 70 patients, there was 1 operative death. Based on our typing system, the tumors were assigned as early HCC (n ‫؍‬ 15), overt HCC (n ‫؍‬ 52), and non-HCC tumor (n ‫؍‬ 3). The rate of microscopic regional spread was lower in early HCCs than in overt HCCs (7% vs. 42%; P ‫؍‬ .01). The early HCC group had a longer time to recurrence than did the overt HCC group (3.9 vs. 1.7 years; P F .001) and had no local recurrence. After a median follow-up of 6.3 years, both overall survival and recurrence-free survival in the early HCC group were significantly better than those in the overt HCC group (P ‫؍‬ .01; P ‫؍‬ .001). In these two groups, the 5-year rates of overall survival were 93% and 54% (P ‫؍‬ .01), and those of recurrence-free survival were 47% and 16% (P ‫؍‬ .05), respectively; a significant survival benefit persisted over a decade (57% vs. 21%; P ‫؍‬ .05). The early HCC group was at a lower risk of recurrence (relative risk, 0.31; 95% CI, 0.15 to 0.65; P ‫؍‬ .002) and death (relative risk, 0.26; 95% CI, 0.09 to 0.73; P ‫؍‬ .01) than was the overt HCC group. Early HCC is a distinct clinical entity with a high rate of surgical cure, thereby justifying its definition. It can be a lesion that corresponds to ''Stage 0'' cancer in other organs. (HEPATOLOGY 1998;28:1241-1246

Insulin stimulates glucose transporter (GLUT) 4 vesicle translocation from intracellular storage sites to the plasma membrane in 3T3L1 adipocytes through a VAMP2-and syntaxin 4-dependent mechanism. We have observed that Munc18c, a mammalian homolog of the yeast syntaxin-binding protein n-Sec1p, competed for the binding of VAMP2 to syntaxin 4. Consistent with an inhibitory function for Munc18c, expression of Munc18c, but not the related Munc18b isoform, prevented the insulin stimulation of GLUT4 and IRAP/vp165 translocation to the plasma membrane without any significant effect on GLUT1 trafficking. As expected, overexpressed Munc18c was found to co-immunoprecipitate with syntaxin 4 in the basal state. However, these complexes were found to dissociate upon insulin stimulation. Furthermore, endogenous Munc18c was predominantly localized to the plasma membrane and its distribution was not altered by insulin stimulation. Although expression of enhanced green fluorescent protein-Munc18c primarily resulted in a dispersed cytosolic distribution, co-expression with syntaxin 4 resulted in increased localization to the plasma membrane. Together, these data suggest that Munc18c inhibits the docking/fusion of GLUT4-containing vesicles by blocking the binding of VAMP2 to syntaxin 4. Insulin relieves this inhibition by inducing the dissociation of Munc18c from syntaxin 4 and by sequestering Munc18c to an alternative plasma membrane binding site.The binding of insulin to its heterotetrameric integral-membrane receptor activates its intracellular tyrosine kinase domain and thereby triggers a signaling cascade resulting in the translocation and fusion of intracellular GLUT4 1 isoform-containing vesicles to the plasma membrane (1-3). Although most cell types also constitutively express the GLUT1 isoform at the cell surface, the insulin-stimulated increase in plasma membrane-associated GLUT4 protein accounts for the majority of post-prandial glucose disposal in both muscle and adipose tissue (4).The insulin-stimulated translocation of these GLUT4-containing vesicles has several features in common with the regulated exocytosis pathway of synaptic vesicle trafficking in neurotransmitter release (5). The machinery involved in the regulation of synaptic vesicle priming/docking/fusion entails the pairing of protein complexes in the vesicle compartment (v-SNAREs, for vesicle SNAP receptors) with their cognate receptor complexes at the target membrane (t-SNAREs, for target membrane SNAP receptors). Recently, several of the vand t-SNARE proteins have been identified that specifically participate in the insulin-regulated docking and fusion of GLUT4 vesicles with the adipocyte plasma membrane. GLUT4 vesicles co-purify with both the VAMP2 and VAMP3 v-SNARE isoforms and specific proteolytic cleavage of VAMP2, expression of a dominant-interfering VAMP2 mutant or inhibitory peptides impairs insulin-stimulated GLUT4 translocation (6 -11). In addition, transferrin-horseradish peroxidase ablation of recycling endosomes resulted in a selective loss ...

The prognosis of pancreatic cancer is defined by the histology and extent of disease. Preoperative histologic diagnosis and diagnostic imaging are fundamentals in managing the disease, but it is not rare to find unexpected peritoneal dissemination or liver metastasis at the time of operation. The overall resectability rate of pancreatic cancer is 40% in Japan. Resecting the portal vein and peripancreatic plexus were performed on 40% of the patients who underwent pancreatectomy for invasive cancer in the head of the pancreas. Long-term survival was only found in patients who underwent pancreatectomy. Radical lymph node dissection, or combined resection of the large vessels, did not seem to improve survival further than the standard resection. Multidisciplinary treatments combined with surgery were performed, and various effects of postoperative chemotherapy after pancreatectomy, intraoperative- and postoperative-radiation therapy, or postoperative chemotherapy for unresectable tumor, were shown. Development of unconventional therapies and refinement of the conventional therapy should be promoted on a randomized prospective trial basis. To promote this effort, which requires the international comparisons and cooperation, JPS developed a computerized JPS registration system downloadable from the JPS website (http://www.kojin.or.jp/suizou/index.html).

BACKGROUNDIt is not rare to find satellite lesions in patients with small hepatocellular carcinoma (HCC). The purpose of this study was to elucidate the factors associated with satellite lesions in these patients.METHODSWe investigated the prevalence of satellite lesions, the relationship of clinicopathologic factors to satellite lesions, and the distance from the main tumor to the satellite lesion in 149 patients. Patients, who had a solitary HCC of 3.0 cm or less in diameter but no satellite lesions on preoperative imaging procedures, underwent potentially curative resection. The main tumors were macroscopically classified into four groups: early HCC, a vaguely nodular type showing preservation of the preexisting liver structure; single nodular type; single nodular type with extranodular growth; and confluent multinodular type.RESULTSOf 149 resected specimens, 28 (19%) showed satellite lesions. Of the clinicopathologic factors investigated, the macroscopic type and tumor differentiation were significantly associated with the prevalence of satellite lesions. Both the single nodular type with extranodular growth and the confluent multinodular type showed satellite lesions more frequently than the early HCC and the single nodular type. A significantly higher prevalence of satellite lesions was observed in poorly differentiated HCC than in well and moderately differentiated HCC. The satellite lesions were located 0.5 cm or less from the main tumor in 8 (33%) specimens, 0.6–1.0 cm in 12 (50%), and 1.1–2.0 cm in 4 (17%). No identifiable factors were significantly related to the distance from the main tumor to the satellite lesion. However, all satellite lesions located more than 1.0 cm from the main tumor coexisted with poorly differentiated HCC, which were the single nodular type with extranodular growth or the confluent multinodular type.CONCLUSIONIn the single nodular type with extranodular growth, confluent multinodular type, and poorly differentiated HCC, extensive treatment achieving a large safety margin and/or frequent posttreatment follow‐up examinations may be needed because of the high prevalence of satellite lesions. Cancer 2002;95:1931–7. © 2002 American Cancer Society.DOI 10.1002/cncr.10892

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In addition to tyrosine phosphorylation of the 66-, 52-, and 46-kDa Shc isoforms, epidermal growth factor (EGF) treatment of Chinese hamster ovary cells expressing the human EGF receptor also resulted in the serine/ threonine phosphorylation of approximately 50% of the 66-kDa Shc proteins. The serine/threonine phosphorylation occurred subsequent to tyrosine phosphorylation and was prevented by pretreatment of the cells with the MEK-specific inhibitor PD98059. Surprisingly, only the gel-shifted 66-kDa Shc isoform (serine/threonine phosphorylated) was tyrosine phosphorylated and associated with Grb2. In contrast, only the non-serine/threonine-phosphorylated fraction of 66-kDa Shc was associated with the EGF receptor. To assess the relationship between the three Shc isoforms in EGF-stimulated signaling, the cDNA encoding the 66-kDa Shc species was cloned from a 16-day-old mouse embryo library. Sequence alignment confirmed that the 66-kDa Shc cDNA resulted from alternative splicing of the primary Shc transcript generating a 110-amino acid extension at the amino terminus. Co-immunoprecipitation of Shc and Grb2 from cells overexpressing the 52/46-kDa Shc isoforms versus the 66-kDa Shc species directly demonstrated a competition of binding for a limited pool of Grb2 proteins. Furthermore, expression of the 66-kDa Shc isoform markedly accelerated the inactivation of ERK following EGF stimulation. Together, these data indicate that the serine/threonine phosphorylation of 66-kDa Shc impairs its ability to associate with the tyrosine-phosphorylated EGF receptor and can function in a dominant-interfering manner by inhibiting EGF receptor downstream signaling pathways.The epidermal growth factor (EGF) 1 receptor is one member of a large family of receptor tyrosine kinases that undergoes ligand-stimulated autophosphorylation and can tyrosine phosphorylate a distinct set of endogenous protein substrates (1-5). The phosphorylation of these tyrosine residues generates recognition motifs for Src homology 2 (SH2) and phosphotyrosine binding (PTB) domains present in various intracellular signaling molecules (6 -12). The association of tyrosine-phosphorylated receptors and substrates with these effector proteins generates multisubunit signaling complexes responsible for downstream biological responsiveness. One important proximal target for the EGF receptor was originally identified as a series of proteins (66, 52, and 46 kDa), termed Shc for Src homology 2/␣-collagen related (13). Although the carboxyl-terminal SH2 domain was originally presumed to be responsible for its association with the tyrosine-phosphorylated EGF receptor, recent studies have demonstrated that the amino-terminal PTB domain is primarily responsible for EGF receptor association (14 -16). Thus, it is now thought that the Shc SH2 domain appears to play a secondary role by enhancing the affinity of interaction between the Shc proteins and the tyrosine-phosphorylated EGF receptor (8,13,15,(17)(18)(19)(20).In addition to the binding of Shc to the activated EGF recep...