Survival rates of early-stage HCV-related liver cirrhosis patients without hepatocellular carcinoma are decreased by alcohol

Although alcohol abuse is the most common cause of liver cirrhosis in the United States, the enhancing effects of alcohol on the long-term prognosis of hepatitis C virus (HCV) related liver cirrhosis has not been clarified. To investigate how alcohol abuse influences the prognosis of hepatitis virus related liver cirrhosis, we studied 716 Japanese patients. Cumulative survival and hepatocellular carcinoma (HCC) development rates were analyzed in alcohol abusive, cirrhotic patients with or without hepatitis virus infection. Patients who abused alcohol were younger (p<0.0001) than HCV infected, non-abusive patients. The overall survival rate among patients with alcoholic cirrhosis (Al group), HCV related cirrhosis (HCV group), and HCV infected + alcoholic cirrhosis (HCV + Al group), showed no significant differences, although the 10-year cumulative survival rate of Al group was the highest of the three groups. The HCC development rate of Al group was the lowest. In addition, alcohol abuse decreased the survival rates of HCV group in the early stage with no HCC (p = 0.0028). In conclusion, alcohol abuse might affect the progression of liver damage in HCV infected patients with liver cirrhosis in the early stage, although the influence of alcohol abuse on the long term prognosis seems to be rather small

Restriction-modification system with methyl-inhibited base excision and abasic-site cleavage activities

The restriction-modification systems use epigenetic modification to distinguish between self and nonself DNA. A modification enzyme transfers a methyl group to a base in a specific DNA sequence while its cognate restriction enzyme introduces breaks in DNA lacking this methyl group. So far, all the restriction enzymes hydrolyze phosphodiester bonds linking the monomer units of DNA. We recently reported that a restriction enzyme (R.PabI) of the PabI superfamily with half-pipe fold has DNA glycosylase activity that excises an adenine base in the recognition sequence (5′-GTAC). We now found a second activity in this enzyme: at the resulting apurinic/apyrimidinic (AP) (abasic) site (5′-GT#C, # = AP), its AP lyase activity generates an atypical strand break. Although the lyase activity is weak and lacks sequence specificity, its covalent DNA–R.PabI reaction intermediates can be trapped by NaBH[subscript 4] reduction. The base excision is not coupled with the strand breakage and yet causes restriction because the restriction enzyme action can impair transformation ability of unmethylated DNA even in the absence of strand breaks in vitro. The base excision of R.PabI is inhibited by methylation of the target adenine base. These findings expand our understanding of genetic and epigenetic processes linking those in prokaryotes and eukaryotes

Identification of Dietary Phytochemicals Capable of Enhancing the Autophagy Flux in HeLa and Caco-2 Human Cell Lines

Autophagy is a major degradation system for intracellular macromolecules. Its decline with age or obesity is related to the onset and development of various intractable diseases. Although dietary phytochemicals are expected to enhance autophagy for preventive medicine, few studies have addressed their effects on the autophagy flux, which is the focus of the current study. Herein, 67 dietary phytochemicals were screened using a green fluorescent protein (GFP)-microtubule-associated protein light chain 3 (LC3)-red fluorescent protein (RFP)-LC3ΔG probe for the quantitative assessment of autophagic degradation. Among them, isorhamnetin, chrysoeriol, 2,2′,4′-trihydroxychalcone, and zerumbone enhanced the autophagy flux in HeLa cells. Meanwhile, analysis of the structure–activity relationships indicated that the 3′-methoxy-4′-hydroxy group on the B-ring in the flavone skeleton and an ortho-phenolic group on the chalcone B-ring were crucial for phytochemicals activities. These active compounds were also effective in colon carcinoma Caco-2 cells, and some of them increased the expression of p62 protein, a typical substrate of autophagic proteolysis, indicating that phytochemicals impact p62 levels in autophagy-dependent and/or -independent manners. In addition, these compounds were characterized by distinct modes of action. While isorhamnetin and chrysoeriol enhanced autophagy in an mTOR signaling-dependent manner, the actions of 2,2′,4′-trihydroxychalcone and zerumbone were independent of mTOR signaling. Hence, these dietary phytochemicals may prove effective as potential preventive or therapeutic strategies for lifestyle-related diseases

Interplay of a non-conjugative integrative element and a conjugative plasmid in the spread of antibiotic resistance via suicidal plasmid transfer from an aquaculture Vibrio isolate

The capture of antimicrobial resistance genes (ARGs) by mobile genetic elements (MGEs) plays a critical role in resistance acquisition for human-associated bacteria. Although aquaculture environments are recognized as important reservoirs of ARGs, intra- and intercellular mobility of MGEs discovered in marine organisms is poorly characterized. Here, we show a new pattern of interspecies ARGs transfer involving a ‘non-conjugative’ integrative element. To identify active MGEs in a Vibrio ponticus isolate, we conducted whole-genome sequencing of a transconjugant obtained by mating between Escherichia coli and Vibrio ponticus. This revealed integration of a plasmid (designated pSEA1) into the chromosome, consisting of a self-transmissible plasmid backbone of the MOBH group, ARGs, and a 13.8-kb integrative element Tn6283. Molecular genetics analysis suggested a two-step gene transfer model. First, Tn6283 integrates into the recipient chromosome during suicidal plasmid transfer, followed by homologous recombination between the Tn6283 copy in the chromosome and that in the newly transferred pSEA1. Tn6283 is unusual among integrative elements in that it apparently does not encode transfer function and its excision barely generates unoccupied donor sites. Thus, its movement is analogous to the transposition of insertion sequences rather than to that of canonical integrative and conjugative elements. Overall, this study reveals the presence of a previously unrecognized type of MGE in a marine organism, highlighting diversity in the mode of interspecies gene transfer

Interplay of a non-conjugative integrative element and a conjugative plasmid in the spread of antibiotic resistance via suicidal plasmid transfer from an aquaculture Vibrio isolate

<div><p>The capture of antimicrobial resistance genes (ARGs) by mobile genetic elements (MGEs) plays a critical role in resistance acquisition for human-associated bacteria. Although aquaculture environments are recognized as important reservoirs of ARGs, intra- and intercellular mobility of MGEs discovered in marine organisms is poorly characterized. Here, we show a new pattern of interspecies ARGs transfer involving a ‘non-conjugative’ integrative element. To identify active MGEs in a <i>Vibrio ponticus</i> isolate, we conducted whole-genome sequencing of a transconjugant obtained by mating between <i>Escherichia coli</i> and <i>Vibrio ponticus</i>. This revealed integration of a plasmid (designated pSEA1) into the chromosome, consisting of a self-transmissible plasmid backbone of the MOB_H group, ARGs, and a 13.8-kb integrative element Tn<i>6283</i>. Molecular genetics analysis suggested a two-step gene transfer model. First, Tn<i>6283</i> integrates into the recipient chromosome during suicidal plasmid transfer, followed by homologous recombination between the Tn<i>6283</i> copy in the chromosome and that in the newly transferred pSEA1. Tn<i>6283</i> is unusual among integrative elements in that it apparently does not encode transfer function and its excision barely generates unoccupied donor sites. Thus, its movement is analogous to the transposition of insertion sequences rather than to that of canonical integrative and conjugative elements. Overall, this study reveals the presence of a previously unrecognized type of MGE in a marine organism, highlighting diversity in the mode of interspecies gene transfer.</p></div

R-mini CHP in ≥80-year-old Patients with Diffuse Large B-cell Lymphoma: A Multicenter, Open-label, Single-arm Phase II Trial Protocol

In very-elderly diffuse large B-cell lymphoma (DLBCL) patients, treatment intensities must be lowered due to the risks of comorbidities and organ function deterioration, and treatment outcomes are worse compared to younger patients. Very-elderly patients are often excluded from DLBCL clinical trials, and optimal treatments and dosages are not established. In this clinical trial, we examined the efficacy and safety of 6 courses of R-mini CHP therapy (cf., CHOP [cyclophosphamide, doxorubicin, vincristine, and prednisone]) in which vincristine is omitted to avoid the peripheral neuropathy that reduces elderly patients’ quality of life, as remission induction therapy in DLBCL patients aged≥80 years

Cell Type-Specific Transcriptome of Brassicaceae Stigmatic Papilla Cells From a Combination of Laser Microdissection and RNA Sequencing

Pollination is an early and critical step in plant reproduction, leading to successful fertilization. It consists of many sequential processes, including adhesion of pollen grains onto the surface of stigmatic papilla cells, foot formation to strengthen pollen-stigma interaction, pollen hydration and germination, and pollen tube elongation and penetration. We have focused on an examination of the expressed genes in papilla cells, to increase understanding of the molecular systems of pollination. From three representative species of Brassicaceae (Arabidopsis thaliana, A. halleri and Brassica rapa), stigmatic papilla cells were isolated precisely by laser microdissection, and cell type-specific gene expression in papilla cells was determined by RNA sequencing. As a result, 17,240, 19,260 and 21,026 unigenes were defined in papilla cells of A. thaliana, A. halleri and B. rapa, respectively, and, among these, 12,311 genes were common to all three species. Among the17,240 genes predicted in A. thaliana, one-third were papilla specific while approximately half of the genes were detected in all tissues examined. Bioinformatics analysis revealed that genes related to a wide range of reproduction and development functions are expressed in papilla cells, particularly metabolism, transcription and membrane-mediated information exchange. These results reflect the conserved features of general cellular function and also the specific reproductive role of papilla cells, highlighting a complex cellular system regulated by a diverse range of molecules in these cells. This study provides fundamental biological knowledge to dissect the molecular mechanisms of pollination in papilla cells and will shed light on our understanding of plant reproduction mechanism

Lysophosphatidic acid stimulates the proliferation and motility of malignant pleural mesothelioma cells through lysophosphatidic acid receptors, LPA1 and LPA2

金沢大学がん研究所分子標的がん医療研究開発センターLysophosphatidic acid (LPA) is one of the simplest natural phospholipids. This phospholipid is recognized as an extracellular potent lipid mediator with diverse effects on various cells. Although LPA is shown to stimulate proliferation and motility via LPA receptors, LPA1 and LPA2, in several cancer cell lines, the role of LPA and LPA receptors for malignant pleural mesothelioma (MPM) has been unknown. MPM is an aggressive malignancy with a poor prognosis and the incidence is increasing and is expected to increase further for another 10-20 years worldwide. Therefore, the development of novel effective therapies is needed urgently. In this study, we investigated the effect of LPA on the proliferation and motility of MPM cells. We found that all 12 cell lines and four clinical samples of MPM expressed LPA1, and some of them expressed LPA2, LPA3, LPA4 and LPA5. LPA stimulated the proliferation and motility of MPM cells in a dose-dependent manner. Moreover, LPA-induced proliferation was inhibited by Ki16425, an inhibitor of LPA1, and small interfering RNA against LPA1, but not LPA2. Interestingly, LPA-induced motility was inhibited by small interfering RNA against LPA2, but not LPA1, unlike a number of previous reports. These results indicate that LPA is a critical factor on proliferation though LPA1, and on motility though LPA2 in MPM cells. Therefore, LPA and LPA receptors, LPA2 as well as LPA1, represent potential therapeutic targets for patients with MPM. © 2008 Japanese Cancer Association

Intensification therapy with anti-parathyroid hormone-related protein antibody plus zoledronic acid for bone metastases of small cell lung cancer cells in severe combined immunodeficient mice

金沢大学附属病院がん高度先進治療センターBone metastases occur in more than one-third of patients with advanced lung cancer and are difficult to treat. We showed previously the therapeutic effect of a third-generation bisphosphonate, minodronate, and antiparathyroid hormone-related protein (PTHrP) neutralizing antibody on bone metastases induced by the human small cell lung cancer cell line, SBC-5, in natural killer cell-depleted severe combined immunodeficient mice. The purpose of our current study was to examine the effect of the combination of PTHrP antibody and zoledronic acid, which has been approved to treat bone metastases, against bone metastases produced by SBC-5 cells expressing PTHrP. Treatment with PTHrP antibody and/or zoledronic acid did not affect the proliferation of SBC-5 cells in vitro. Repeated treatments with either PTHrP antibody or zoledronic acid inhibited the formation of osteolytic bone metastases of SBC-5 cells but had no effect on metastases to visceral organs. Importantly, combined treatment with PTHrP antibody and zoledronic acid further inhibited the formation of bone metastases. Histologic assays showed that, compared with either PTHrP antibody or zoledronic acid alone, their combination decreased the number of tumor-associated osteoclasts and increased the number of apoptotic tumor cells. These findings suggest that this novel dual-targeting therapy may be useful for controlling bone metastases in a subpopulation of small cell lung cancer patients. Copyright © 2009 American Association for Cancer Research.全文公開20100