Extensive gene deletions in Japanese patients with Diamond-Blackfan anemia

Fifty percent of Diamond-Blackfan anemia (DBA) patients possess mutations in genes coding for ribosomal proteins (RPs). To identify new mutations, we investigated large deletions in the RP genes RPL5, RPL11, RPL35A, RPS7, RPS10, RPS17, RPS19, RPS24, and RPS26. We developed an easy method based on quantitative-PCR in which the threshold cycle correlates to gene copy number. Using this approach, we were able to diagnose 7 of 27 Japanese patients (25.9%) possessing mutations that were not detected by sequencing. Among these large deletions, similar results were obtained with 6 of 7 patients screened with a single nucleotide polymorphism array. We found an extensive intragenic deletion in RPS19, including exons 1-3. We also found 1 proband with an RPL5 deletion, 1 patient with an RPL35A deletion, 3 with RPS17 deletions, and 1 with an RPS19 deletion. In particular, the large deletions in the RPL5 and RPS17 alleles are novel. All patients with a large deletion had a growth retardation phenotype. Our data suggest that large deletions in RP genes comprise a sizable fraction of DBA patients in Japan. In addition, our novel approach may become a useful tool for screening gene copy numbers of known DBA genes.     

Safety and effectiveness of switching from infliximab to etanercept in patients with rheumatoid arthritis: results from a large Japanese postmarketing surveillance study

Finding an effective treatment strategy for rheumatoid arthritis (RA) patients who have not benefited from previous tumor necrosis factor–α antagonist treatment is important for minimizing RA disease activity and improving patient outcomes. The aim of this study was to compare the safety and effectiveness of etanercept in patients with and without infliximab (IFX) treatment experience. Patients (n?=?7,099) from a large postmarketing observational study of etanercept use in Japan were divided into 2 cohorts based on previous IFX use (pre-IFX and non-IFX). Baseline characteristics were assessed in each cohort. Adverse events (AEs) and European League Against Rheumatism (EULAR) responses were monitored every 4?weeks for 24?weeks. At baseline, pre-IFX patients were younger and had fewer comorbidities and a shorter RA duration than non-IFX patients. During the study, pre-IFX patients received concomitant methotrexate more often than non-IFX patients. The incidence of AEs and serious AEs were significantly lower in pre-IFX patients, as was the percentage of patients who discontinued treatment. Both cohorts had significant improvement (P?<?0.001) in EULAR responses at the end of the treatment period. This study demonstrated that etanercept was effective and well tolerated in active RA patients with and without prior IFX treatment.     

Plasma cells and the chronic nonsuppurative destructive cholangitis of primary biliary cirrhosis

There has been increased interest in the role of B cells in the pathogenesis of primary biliary cirrhosis (PBC). Although the vast majority of patients with this disease have anti-mitochondrial antibodies, there is no correlation of anti-mitochondrial antibody titer and/or presence with disease severity. Furthermore, in murine models of PBC, it has been suggested that depletion of B cells may exacerbate biliary pathology. To address this issue, we focused on a detailed phenotypic characterization of mononuclear cell infiltrates surrounding the intrahepatic bile ducts of patients with PBC, primary sclerosing cholangitis, autoimmune hepatitis, chronic hepatitis C, and graft-versus-host disease, including CD3, CD4, CD8, CD20, CD38, and immunoglobulin classes, as well as double immunohistochemical staining for CD38 and IgM. Interestingly, CD20 B lymphocytes, which are a precursor of plasma cells, were found in scattered locations or occasionally forming follicle-like aggregations but were not noted at the proximal location of chronic nonsuppurative destructive cholangitis. In contrast, there was a unique and distinct coronal arrangement of CD38 cells around the intrahepatic ducts in PBC but not controls; the majority of such cells were considered plasma cells based on their expression of intracellular immunoglobulins, including IgM and IgG, but not IgA. Patients with PBC who manifest this unique coronal arrangement were those with significantly higher titers of anti-mitochondrial antibodies. CONCLUSION: These data collectively suggest a role for plasma cells in the specific destruction of intrahepatic bile ducts in PBC and confirm the increasing interest in plasma cells and autoimmunity.     

Peroxisome proliferator-activated receptor alpha induction of uncoupling protein 2 protects against acetaminophen-induced liver toxicity

Acetaminophen (APAP) overdose causes acute liver failure in humans and rodents due in part to the destruction of mitochondria as a result of increased oxidative stress followed by hepatocellular necrosis. Activation of the peroxisome proliferator-activated receptor alpha (PPARα), a member of the nuclear receptor superfamily that controls the expression of genes encoding peroxisomal and mitochondrial fatty acid β-oxidation enzymes, with the experimental ligand Wy-14,643 or the clinically used fibrate drug fenofibrate, fully protects mice from APAP-induced hepatotoxicity. PPARα-humanized mice were also protected, whereas Ppara-null mice were not, thus indicating that the protection extends to human PPARα and is PPARα-dependent. This protection is due in part to induction of the PPARα target gene encoding mitochondrial uncoupling protein 2 (UCP2). Forced overexpression of UCP2 protected wildtype mice against APAP-induced hepatotoxicity in the absence of PPARα activation. Ucp2-null mice, however, were sensitive to APAP-induced hepatotoxicity despite activation of PPARα with Wy-14,643. Protection against hepatotoxicity by UCP2-induction through activation of PPARα is associated with decreased APAP-induced c-jun and c-fos expression, decreased phosphorylation of JNK and c-jun, lower mitochondrial H(2)O(2) levels, increased mitochondrial glutathione in liver, and decreased levels of circulating fatty acyl-carnitines. These studies indicate that the PPARα target gene UCP2 protects against elevated reactive oxygen species generated during drug-induced hepatotoxicity and suggest that induction of UCP2 may also be a general mechanism for protection of mitochondria during fatty acid β-oxidation.     

Maturity-dependent fractionation of neutrophil progenitors: a new method to examine in vivo expression profiles of differentiation-regulating genes

To investigate differentiation-dependent gene expression during granulopoiesis, we established a new method to isolate six sequential differentiation stages of neutrophil progenitors from bone marrow. Neutrophil progenitors were divided into three populations by density centrifugation, followed by depletion of other lineages, and further separated by fluorescence-activated cell sorting based on the expressions of CD34, CD11b, and CD16: CD34(+) fraction from a low-density population (F1), CD11b(-)/CD16(-) (F2), CD11b(+)/CD16(-) (F3), and CD11b(+)/CD16(low) (F4) fractions with intermediate density, and CD11b(+)/CD16(int) (F5) and CD11b(+)/CD16(high) (F6) fractions from a high-density population. To examine whether this fractionation was applicable to the study of in vivo gene expression profiles during granulopoiesis, we analyzed messenger RNA levels of AML-1 and CCAAT/enhancer binding protein (EBP)-ε and two target genes of C/EBP-ε, granulocyte-macrophage colony-stimulating factor receptor common β subunit and lactoferrin, in the six fractions and peripheral blood-derived neutrophils (F7). Expression of AML-1 and C/EBP-ε peaked at F1 and F4, respectively, followed by a gradual decrease. Although granulocyte-macrophage colony-stimulating factor receptor common β subunit messenger RNA levels remained low from F1 through F6 and elevated at F7, lactoferrin messenger RNA showed a drastic increase at F3 and dropped at F5. The difference in the expression profiles of the two C/EBP-ε target genes suggests the involvement of regulators other than C/EBP-ε in the induction of the two genes. The new fractionation method is able to provide new information on maturation-dependent gene expression during granulopoiesis.     

Neuroendocrine carcinoma of the stomach: clinicopathological and immunohistochemical evaluation

Neuroendocrine carcinoma (NEC) of the stomach is an uncommon disease. Because of its rarity, the clinicopathological features are unclear, and there is no consensus on the optimal treatment strategy. This study included five consecutive patients with gastric NEC who underwent surgery from July 2001 to August 2011. Clinical presentation, tumor location, tumor morphology and size, pathology and immunohistochemistry results, and treatment outcome were analyzed retrospectively and discussed. The study cohort of four men and one woman ranged in age from 52 to 84 years, with a median age of 72 years. Positive rates of neuroendocrine markers were 40 % for chromogranin A, 60 % for synaptophysin, 60 % for CD56, 40 % for neuron-specific enolase, and 100 % for p53 protein. Median number of lymph node metastases per patient was 10, with severe lymphatic and venous infiltration, and high Ki-67 labeling index (60–90 %) reported for all patients. Median tumor size was 6 cm. Stage IV disease was diagnosed in three patients; the other two patients showed stage IIIA tumors. After a mean follow-up of 29.8 months, two of the five patients had died of the disease. Although rare, gastric NECs deserve particular attention because of their strong malignant potential associated with an extremely poor prognosis. Such carcinomas demand an aggressive surgical approach followed by chemotherapy and multimodality adjuvant therapy.     

Helicobacter pylori infection and gastric carcinogenesis in rodent models

Helicobacter pylori infection is an important factor for gastric carcinogenesis in human. In carcinogen-treated Mongolian gerbils, H. pylori infection enhances stomach carcinogenesis, while infection alone induced severe hyperplasia called heterotopic proliferative glands. A high-salt diet or early acquisition of the bacteria exacerbates inflammation and carcinogenesis. Oxygen radical scavengers or anti-inflammatory chemicals as well as eradication of H. pylori are effective to prevent carcinogenesis. H. pylori-associated inflammation induces intestinal metaplasia and intestinalization of stomach cancers independently. It is necessary to control cancer development not only in H. pylori-positive cases but also in H. pylori-negative metaplastic gastritis.     

Influence of preoperative dental procedures on the prognosis of patients with squamous cell carcinoma of the gingiva

Our aim was to investigate the prognosis of patients with squamous cell carcinoma (SCC) of the gingiva who had preoperative dental operations. We studied 102 patients who were being operated on for SCC of the gingiva with special reference to the effects of preoperative dental operations on the prognosis. Twenty-six patients had dental procedures such as tooth extraction, or incision, or curettage before they visited our hospital, while the remaining 76 had no such interventions. The percentage of patients with advanced T stage disease (T3 or T4) was higher among those who had interventions (17/26, 65%) than among those who had not (35/76, 46%). The difference was not significant. Histopathologically invaded nodes were detected in half the patients in the intervention group (13/26), while they were found in only 18/76 (24%) of those in the no intervention group (p < 0.02). The incidence of nodal metastases with extranodal spread was significantly higher in the intervention group than in the no intervention group (p < 0.05), and those in the intervention group were more likely to develop distant metastases than those in the other group (p < 0.001). The 5-year survival in the two groups was 65% and 92%, respectively (p < 0.01). Preoperative dental operations such as tooth extraction, incision, or curettage possibly lead to regional and distant metastases and therefore a poor prognosis in patients with SCC of the gingiva.