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We examined nucleotide sequences of Epstein-Barr virus (EBV)-positive Hodgkin/Reed-Sternberg (HRS)-like B cells in a case of diffuse large B-cell lymphoma (DLBCL) and a case of adult T-cell lymphoma (ATL) for single-cell polymerase chain reaction of the immunoglobulin heavy-chain gene variable region (VH gene). HRS-like B cells were scattered in the area irrelevant to the lymphoma infiltrates of DLBCL and in the lymphoma area of ATL. HRS-like B cells were positive for CD20 and CD30 but negative for CD15. EBV presented in HRS-like B cells in both cases but not in any lymphoma cells. VH genes of five HRS-like B cells analyzed in DLBCL were polyclonal and showed in-frame sequences with 0% to 2.8% somatic mutation frequency. In an ATL, VH genes of five HRS-like B cells analyzed were polyclonal and somatically mutated. Four cells carried in-frame rearrangements with 3.5% to 17.7% mutation frequency. One of the VH genes has a one-codon deletion. From the fifth cell, an out-of-frame rearrangement with an insertion and a deletion was obtained. Thus, we showed polyclonal EBV-positive HRS-like B cells in both DLBCL and ATL and that whereas EBV-positive, HRS-like B cells in DLBCL exhibited unmutated and mutated VH gene, those in ATL were found to have a somatically mutated VH gene with/without deletions and/or insertions. The HRS-like B cells may appear because of active EBV infection in a patient who is immunosuppressed from the primary lymphoma.

We have studied the expression of MIB-1 and prognosis in cyclin D1(CyD1) + and CyD1 m mantle cell lymphoma (MCL), and compared them to B-CLL/SLL. All cases were assigned to four groups by immunoreactivity and primary sites: (1) CyD1 + nodal MCL, 11 cases: (2) CyD1 + extranodal MCL (multiple lymphomatous polyposis, (MLP)) three cases: (3) CyD1 m nodal MCL, three cases: and (4) CyD1 m B-CLL/SLL, seven cases. The average of MIB-1 labeling indexes of the four groups were 30.66, 8.70, 9.30 and 4.66, respectively. The CyD1 m group consisting of nodal MCL and CLL/SLL had a significantly longer median survival time (69 months) than the CyD1 + group consisting of nodal MCL and MLP (22 months, P =0.01 ). These data indicate that CyD1 m nodal MCL may show a lower MIB-1 labeling index, and has a better prognosis, than CyD1 + nodal MCL. In addition, a large difference in the average of MIB-1 labeling indexes between nodal MCL and MLP in the CyD1 + group was found.

This paper examines the international portfolio flows of European Union. Our analysis includes three dimensions: (1) the level of countries portfolio investment concentration (those who invest evenly among counterparties versus those who invest more heavily in some counterparties); (2) the share of total portfolio investment assets invested at the destination; and (3) pre- and during the crisis periods. We find that portfolio investment positions respond differently to macroeconomic variables depending on the level of investment concentration and the share of invested assets. In particular, variables of health of the financial system become important determinants for portfolio investment during the crisis.

The MRI findings of amyloid arthropathy associated with primary amyloidosis are presented here possibly for the first time in the literature. Two types of lesions are noted: (1) capsular and tendon lesions; these regions are thickened, hypointense and enhanced by gadolinium (Gd) on T1 weighted imaging (T1WI), and hyperintense on T2 weighted imaging (T2WI), and (2) periarticular and osseous lesions; these regions appear to be tumor-forming and hypointense on both T1WI and T2WI and are not enhanced by Gd. It is necessary to differentiate these findings from other diseases such as chondrosarcoma, rhabdomyosarcoma and chronic inflammatory lesions such as tuberculosis.

We have analyzed the immunoglobulin heavy chain (VH) gene variable regions (CDR2 and FW3) of 101 Japanese cases with peripheral B cell neoplasms. When all except one case with a deletion were graphed by frequency of replacement mutation, the 100 cases could be separated into two groups: 24 cases with zero, one and two mutations (germline or low frequency of somatic mutation); and 76 cases with three or more mutations (medium to high frequency of somatic mutation). While most mantle cell lymphoma cases (11/13) showed germline or low frequency of somatic mutation, all cases of mucosa-associated lymphoid tissue (MALT) lymphoma (11/11), follicular lymphoma (three of three cases), plasma cell myeloma (seven of seven cases) and most cases of diffuse large B cell lymphoma (DLBCL; 42/47) belonged to the latter group. These 76 cases, therefore, may be considered to show somatic hypermutation. More than half of chronic lymphocytic leukemia/small lymphocytic lymphoma cases (CLL/SLL; eight of 13) showed a hypermutated VH gene and the ratio of replacement mutation : silent mutation in CDR2 of CLL/SLL was considerably higher compared with DLBCL and MALT lymphoma, showing somatic hypermutation. When comparing VH gene type of B cell-CLL (B-CLL) among our series and those in the literature, more cases of CD5+ B-CLL in the Western literature have the VH5 and VH6 family types, while more cases in Japan are reported to have VH4 family. The occurrence of VH families in B-CLL between Japanese and Western people seems to be comparable.

The Rho family of low-molecular-weight G proteins, which consists of the Rho, Rac, and Cdc42 subfamilies, regulates the actin cytoskeleton (Hall 1998). Microinjection of constitutive active forms of these proteins into serum-starved fibroblasts demonstrated that Rho stimulates the organization of actin stress fibers, Rac stimulates the formation of lamellipodia or membrane ruffling, and Cdc42 induces the formation of filopodia (Nobes and Hall 1995). Like other G proteins, the Rho-family proteins are activated by guanine nucleotide exchange proteins (GEPs) and inactivated by GTPase-activating proteins (GAPs) (Lamarche and Hall 1994; Nobes and Hall 1994). The catalytic domains of GEPs for Rho share amino-acid sequences with the Dbl-oncogene product; thus, this domain is designated as the Dbl-homology domain (Cerione and Zheng 1996). It has been also reported that PIP2 and lipid kinases bind to and activate Rho family members (Tolias et al. 1995, 1998; Zheng et al. 1996). A third group of Rho regulator is RhoGDI, a GDP-dissociation inhibitor of Rho (Sasaki and Takai 1998). RhoGDI binds to GDP-bound Rho proteins and retains them in the cytoplasm in an inactive form (Sasaki et al. 1993). CrkII is a cellular homolog of the v-Crk oncogene product and consists almost entirely of SH2 and SH3 domains (Matsuda et al. 1992). Two major CrkII SH2-binding proteins are paxillin and p130Cas, both of which are components of focal adhesions (for review, see Kiyokawa et al. 1997). More recently, it has been shown that CrkII–p130Cas complexes regulate integrin-mediated cell movement and spreading (Vuori et al. 1996; Klemke et al. 1998). The amino-terminal SH3 domain of CrkII binds to several proteins; among the most prominent are C3G and DOCK180 (Matsuda and Kurata 1996). Homologs of DOCK180 have recently been isolated from Drosophila melanogaster and Caenorhabditis elegans and designated as mbc and ced-5, respectively (Erickson et al. 1997; Wu and Horvitz 1998). ced-5 mutants are defective in the engulfment of cell corpses and the migration of the gonadal distal tip cells. The latter phenotype was rescued by the expression of human DOCK180. mbc was originally isolated as a gene that was essential for muscle development, suggesting that mbc is also involved in cellular motility. Human DOCK180 also appears to be involved in cytoskeletal reorganization. Expression of membrane-targeted DOCK180 induced spreading of NIH-3T3 cells (Hasegawa et al. 1996). DOCK180 forms a complex with CrkII and p130Cas only after integrin stimulation of NIH-3T3 cells. Expression of DOCK180 with CrkII and p130Cas induces cell spreading and accumulation of DOCK180 at focal adhesions (Kiyokawa et al. 1998). However, the biochemical function of DOCK180 is unknown. Here, we demonstrate that DOCK180 activates and associates with the Rac1 GTPase and that DOCK180 requires Rac1 for the induction of cell spreading in NIH-3T3 cells.

CrkII adaptor protein becomes tyrosine-phosphorylated upon various types of stimulation. We examined whether tyrosine 221, which has been shown to be phosphorylated by c-Abl, was phosphorylated also by other tyrosine kinases, such as epidermal growth factor (EGF) receptor. For this purpose, we developed an antibody that specifically recognizes Tyr221-phosphorylated CrkII, and we demonstrated that CrkII was phosphorylated on Tyr221 upon EGF stimulation. When NRK cells were stimulated with EGF, the tyrosine-phosphorylated CrkII was detected at the periphery of the cells, where ruffling is prominent, suggesting that signaling to CrkII may be involved in EGF-dependent cytoskeletal reorganization. The EGF-dependent phosphorylation of CrkII was also detected in a c-Abl-deficient cell line. Moreover, recombinant CrkII protein was phosphorylated in vitro by EGF receptor. These results strongly suggest that EGF receptor directly phosphorylates CrkII. Mutational analysis revealed that the src homology 2 domain was essential for the phosphorylation of CrkII by EGF receptor but not by c-Abl, arguing that these kinases phosphorylate CrkII by different phosphorylation mechanisms. Finally, we found that the CrkII protein phosphorylated upon EGF stimulation did not bind to the phosphotyrosine-containing peptide and that CrkII initiated dissociation from EGF receptor within 3 min even with the sustained tyrosine phosphorylation of EGF receptor. This result implicated phosphorylation of Tyr221 in the negative regulation of the src homology 2-mediated binding of CrkII to EGF receptor.

Relationship and histogenesis of Hodgkin's disease (HD) and anaplastic large cell lymphoma (ALCL) still remain unclear. Recently, Reed-Sternberg cells or Hodgkin cells in HD with B cell phenotype (B-HD) are considered to originate from germinal center B cells, ALCLs of B cell phenotype (B-ALCL) are involved in diffuse large B cell lymphoma (DLBCL) as anaplastic variant, but an origin of tumor cells of B-ALCL has not been elucidated. We have therefore investigated somatic mutation of the lg heavy chain (IgH) genes among 17 cases of B-ALCL to clarify whether there is a difference in characteristic and origin of tumor cells between B-ALCL, B-HD and DLBCL. Amplificates of IgH variable (V) region of 10 cases by the polymerase chain reaction method were sequenced and compared with reported germ line configurations. Nine cases (90%) with heavily somatic mutations were found. A case with an out-of-frame rearrangement and a case with 9 base pairs insertion were included. The mutation pattern revealed the tumor cells were selected for antibody expression and discriminated from B-HD. These findings suggest the tumor cells of B-ALCL are derived from germinal center or postgerminal center (memory and effector) B cells and an origin of B-ALCL is not different from DLBCL.

The clinicopathological features, the immunophenotype, and the presence of Epstein-Barr virus (EBV)-associated genomes and gene products were examined in 17 cases of CD30 + anaplastic large cell lymphoma (ALCL) of B-cell type. Microscopically, the 17 cases were divided into ten cases of the monomorphic type and seven cases of the pleomorphic type. EBV was detected in 6 of 17 cases (38 per cent) by RNA in situ hybridization (ISH) with EBV-encoded RNA (EBER1). EBER1 + cases consisted of two cases (20 per cent) of the monomorphic type and four cases (57 per cent) of the pleomorphic type. The five EBER1 + cases showed clonality of the EBV genome by Southern blotting, consistent with the presence of EBV in a monoclonal proliferation. The EBV-encoded latent membrane protein 1 (LMP1) was found in all six EBER1 + cases and EBV-encoded nuclear antigen 2 (EBNA2) was present in two cases by immunohistochemistry. No expression of LMP1 or EBNA2 was observed in the EBER1 - cases. The EBER1 + cases had a tendency for a more favourable prognosis than the EBER1 - cases. It is concluded that EBV has an association with CD30+ ALCL of B-cell type in the Japanese population studied, and especially with the large pleomorphic type. EBV infection may play a pathoaetiological role and may influence clinical behaviour.

CRK protein, together with GRB2/ASH and Nck proteins, belongs to the adaptor-type Src homology (SH)2-containing molecules, which transduce signals from tyrosine kinases. Here another guanine nucleotide-releasing protein (GNRP), C3G, has been identified as a CRK SH3-binding protein. The nucleotide sequence of a 4.1-kb C3G cDNA contains a 3.2-kb open reading frame encoding a 121-kDa protein, and antibodies against C3G have been shown to detect a protein of 130-140 kDa. The carboxyl terminus of C3G has a peptide sequence homologous to GNRPs for Ras, and the expression of this carboxyl terminus region suppresses the loss of CDC25 function in the yeast Saccharomyces cerevisiae. The C3G protein expressed in Escherichia coli binds to CRK and GRB2/ASH proteins. Mutational analysis of C3G assigns the SH3 binding region to a 50-amino acid region containing a proline-rich sequence. The mRNAs of both the C3G and CRK proteins are expressed ubiquitously in human adult and fetal tissues. The results of these studies suggest that the complex of CRK and C3G, or GRB2/ASH and C3G, may transduce the signals from tyrosine kinases to Ras in a number of different tissues.

Epidermal growth factor (EGF) receptor (EGFR) can induce cell growth and transformation in a ligand-dependent manner. To examine whether the autophosphorylation of EGFR correlates with the capacity of the activated EGFR to induce cell growth and transformation, we truncated the human EGFR just after residue 1011, removing all three major autophosphorylation sites (DEL1011). Further, a point mutation was introduced at another autophosphorylation site, Tyr-992-->Phe (DEL1011+F992). The wild-type and mutant receptors were stably expressed in a NIH 3T3 variant cell line that expresses an extremely low level of endogenous EGFR and does not grow with EGF. As expected, DEL1011 and DEL1011+F992 were found to be severely impaired in EGF-induced autophosphorylation, due to the deletion of the appropriate target tyrosines. However, mutant receptors still could induce EGF-dependent DNA synthesis, morphological transformation, and anchorage-independent growth, although the extent of these was significantly reduced when compared with wild-type EGFR. EGF-induced tyrosine phosphorylation of Ras-GTPase activating protein-associated protein p62 and phospholipase C gamma 1 was dramatically reduced in the cells expressing DEL1011 and DEL1011+F992. On the other hand, tyrosine phosphorylation of Shc, complex formation of Shc-Grb2/Ash, and activation of microtubule-associated protein kinase were still fully induced upon EGF stimulation without binding of Shc or Grb2/Ash to the mutant receptor. Thus, tyrosine phosphorylation of Shc may play a crucial role for activating Ras and generating mitotic signals by the activated EGFR mutant.

AIM: To compare the outcome of surgical treatment of colorectal adenocarcinoma in elderly and younger patients. METHODS: The outcomes of 122 patients with colorectal adenocarcinoma who underwent surgical treatment between January 2004 and June 2009 were analyzed. The clinicopathological and blood biochemistry data of the younger group (< 75 years) and the elderly group (≥ 75 years) were compared. RESULTS: There were no significant differences between the two groups in operation time, intraoperative blood loss, hospital stay, time to resumption of oral intake, or morbidity. The elderly group had a significantly higher rate of hypertension and cardiovascular disease. The perioperative serum total protein and albumin levels were significantly lower in the elderly than in the younger group. The serum carcinoembryonic antigen level was lower in the elderly than in the younger group, and there was a significant decreasing trend after the operation in the elderly group. CONCLUSION: The short-term outcomes of surgical treatment in elderly patients with colorectal adenocarcinoma were acceptable. Surgical treatment in elderly patients was considered a selectively effective approach.

An involvement of protein tyrosine kinase in the transduction of the signals initiated by nerve growth factor (NGF) was investigated. A tyrosine kinase inhibitor, herbimycin, inhibited neurite outgrowth of rat pheochromocytoma PC12 cells induced by NGF but not that by dibutyryl-cAMP. Herbimycin and genistein blocked NGF-dependent activation of ras p21 whose essential function in neuronal differentiation has been reported. These observations suggested that tyrosine kinase activity is involved in the signaling pathways. K-252a, by contrast, inhibited NGF-induced but not EGF-dependent activation of ras p21. Tyrosine kinase activity of gp140trk, a constituent of NGF receptor, is activated by NGF for much a longer period compared to the activation of EGF receptor autokinase activity by EGF. We further demonstrated that autophosphorylation of gp140trk is selectively inhibited by K-252a.

Dialkoxyborylbis(bromozincio)methane was prepared from dialkoxyboryldibromomethane by the Pb-catalyzed reaction with zinc. The dialkoxyborylbis(bromozincio)methane afforded vinylboranes by TiCl4-mediated reaction with aldehydes or ketones. The reagent also coupled doubly with an equivalent organic halide under an influence of transition metal salts.

Human DOCK180, which was originally identified as a major protein bound to the Crk oncogene product, is an archetype of the CDM family of proteins, including Ced-5 of Caenorhabditis elegans and Mbc of Drosophila melanogaster. After DOCK180, at least three putative human proteins that manifest high amino acid sequence similarity to DOCK180 have been registered in the GenBank/EMBL database. We have designated one of them, KIAA0209, as DOCK2 and characterize here. DOCK2 mRNA was expressed mostly in peripheral blood cells, followed by slight expression in the spleen and thymus, whereas DOCK180 was expressed in all tissues tested except in peripheral blood cells. Immunostaining of human cadaver tissues revealed that the expression of DOCK2 was limited to the lymphocytes and macrophages of various organs. DOCK2 bound to and activated Rac1, as did DOCK180; however, DOCK2 did not bind to CrkII, which transduces signals at focal adhesions. Thus, DOCK180 and DOCK2 are regulators of Rac and function in adherent and non-adherent cells, respectively.

Background Lymphomatosis cerebri (LC) is a rare subtype of primary central nervous system malignant lymphoma. The typical features of this disease exhibited on magnetic resonance imaging (MRI) without contrast enhancement are similar to those observed with diffuse leukoencephalopathy, mimicking white matter disorders such as encephalitis. Clinical features and examination findings that are suggestive of inflammatory diseases may indeed confound the diagnosis of LC. Case presentation A 66-year-old woman with continuous fever over a two-month period developed left hemiparesis despite presenting in an alert state with normal cognitive function. Sampling tests showed autoantibodies in the serum and inflammatory changes in the cerebrospinal fluid. The results from an MRI demonstrated multiple non-enhanced brain lesions in the splenium of the corpus callosum and deep white matter. Single photon emission computed tomography revealed increases in blood flow in the basal ganglia, thalamus and brainstem. No systemic malignancies were found. The patient was suspected of having a diagnosis of nonvasculitic autoimmune inflammatory meningoencephalitis and treated with intravenous methylprednisolone pulse therapy. Her fever transiently dropped to within the normal range. However, she had a sudden seizure and a second MRI exhibited infiltrative lesions gradually extending throughout the whole brain. We performed a brain biopsy, and LC was histologically diagnosed. The patient received whole-brain radiation therapy, which diminished the fever and seizures. The patient died one year after the initial onset of fever. Conclusions The present case yields an important consideration that brain neoplasms, especially LC, cannot be ruled out, even in cases with clinical characteristics and examinations consistent with inflammatory diseases. Careful follow-up and histological study are vital for the correct diagnosis of LC.