In Japan, systemic chemotherapy is the standard treatment for unresectable, advanced, or recurrent gastric cancer. However, numerous patients with gastric cancer do not receive late-line treatment because of the rapid progression of gastric cancer. Additionally, late-line treatments, such as nivolumab, trifluridine tipiracil (FTD/TPI), or irinotecan, have limited effects on improving clinical symptoms and delaying the onset of symptoms associated with cancer progression.
View Article and Find Full Text PDFLong interspersed nuclear element (LINE) is known to be transposed by reverse transcription using its RNA transcript. Recognition of the 3' stem-loop of LINE RNA by its reverse transcriptase (RT) is an important step of the retrotransposition. Our previous study revealed that the second G residue (G8) in the GGAUA loop of a 17mer LINE RNA from eel, UnaL2-17, is recognized by its RT and the U residue (U10) in the same loop is required to maintain the loop structure (Baba S, Kajikawa M, Okada N, Kawai G.
View Article and Find Full Text PDFGastric Cancer
July 2017
Background: Postoperative malnutrition after gastrectomy is deemed inevitable, which could have prejudicial influence on survival for gastric cancer patients. A prospective feasibility study was conducted to evaluate the efficacy of postoperative oral nutritional supplements.
Methods: Stage I-III gastric cancer patients who underwent distal or total gastrectomy received oral administration of Racol NF (Otsuka Pharmaceutical Factory, Japan), a liquid enteral nutritional formula, as a supplement to regular meals.
Long interspersed elements (LINEs), or non-long-terminal repeat (LTR) retrotransposons, are mobile genetic elements that exist in the genomic DNA of most eukaryotes, comprising a considerable portion of the host chromosomes. LINEs constitute endogenous mutagens that cause insertional mutations in host chromosomes and have a large impact on host genome evolution. Despite their importance, however, the molecular mechanism of LINE retrotransposition is not fully understood.
View Article and Find Full Text PDFA man in his thirties visited our hospital for an evaluation of a 12×10-mm pancreatic solid tumor that was accidentally detected on computed tomography performed for follow-up of familial adenomatous polyposis (FAP). We diagnosed the patient with a solid pseudopapillary neoplasm (SPN) based on endoscopic ultrasound-guided fine-needle aspiration, and he underwent pancreaticoduodenectomy. Small SPN tumors appear as solid tumors, without typical features of SPN, making the definitive diagnosis more difficult.
View Article and Find Full Text PDFNucleic Acids Res
December 2014
To elucidate the molecular mechanism of the integration of long interspersed elements (LINEs), we characterized the 5' ends of more than 200 LINE de novo retrotransposition events into chicken DT40 or human HeLa cells. Human L1 inserts produced 15-bp target-site duplications (TSDs) and zebrafish ZfL2-1 inserts produced 5-bp TSDs in DT40 cells, suggesting that TSD length depends on the LINE species. Further analysis of 5' junctions revealed that the 5'-end-joining pathways of LINEs can be divided into two fundamental types-annealing or direct.
View Article and Find Full Text PDFLINEs mobilize their own copies via retrotransposition. LINEs can be divided into two types. One is a stringent type, which constitutes a majority of LINEs.
View Article and Find Full Text PDFThe Long interspersed element 1 (LINE1 or L1) retrotransposon constitutes 17% of the human genome. There are currently 80-100 human L1 elements that are thought to be active in any diploid human genome. These elements can mobilize into new locations of the genome, resulting in changes in genomic information.
View Article and Find Full Text PDFWe report a rare case of intraductal papillary mucinous carcinoma (IPMC) with acute obstructive suppurative pancreatic ductitis (AOSPD), liver abscess, and pancreatobiliary fistula formation. A man in his sixties was admitted to our hospital with a chief complain of high grade fever and anorexia. CT and MRI revealed a multilocular cystic lesion in the pancreatic head, fistula formation between the common bile duct and this cystic lesion, and multiple liver abscess.
View Article and Find Full Text PDFThe zebrafish long interspersed element (LINE), ZfL2-1, which belongs to the L2 clade, contains two open reading frames, ORF1 and ORF2. ORF1 encodes a protein containing a coiled-coil motif and an esterase domain, whereas ORF2 encodes a protein containing an endonuclease and a reverse transcriptase domain. To elucidate the functional significance of ORF1 in retrotransposition, we constructed many variants of ZfL2-1 and examined their retrotransposition ability.
View Article and Find Full Text PDFLong interspersed elements (LINEs) are transposable elements that exist in the chromosomal DNA of most eukaryotes; as such, they have a large impact on the genome evolution of their hosts. LINEs mobilize by a mechanism called retrotransposition in which the LINE RNA is reverse-transcribed into DNA and then integrated into the host chromosome. The integration of the 3' end of the LINE element simultaneously occurs with the initiation of reverse transcription; this process is called target-primed reverse transcription and is one of the important characteristics of LINEs.
View Article and Find Full Text PDFLong interspersed elements (LINEs) are mobile elements that comprise a large proportion of many eukaryotic genomes. Although some LINE-encoded open reading frame 1 proteins (ORF1ps) were suggested to be required for LINE mobilization through binding to their RNA, their general role is not known. The ZfL2-1 ORF1p, which belongs to the esterase-type ORF1p, is especially interesting because it has no known RNA-binding domain.
View Article and Find Full Text PDFLong interspersed elements (LINEs) are transposable elements that proliferate within eukaryotic genomes, having a large impact on eukaryotic genome evolution. LINEs mobilize via a process called retrotransposition. Although the role of the LINE-encoded protein(s) in retrotransposition has been extensively investigated, the participation of host-encoded factors in retrotransposition remains unclear.
View Article and Find Full Text PDFThis is an account of a case of primary adenocarcinoma of the small intestine successfully treated with chemotherapy. A 46-year-old man was admitted with a complaint of severe abdominal distension. Abdominal computerized tomography revealed bowel obstruction, and this was found at surgery to be due to a tumor at the jejunum 100 cm distal from the Treitz ligament.
View Article and Find Full Text PDFLong interspersed elements (LINEs) are autonomous transposable elements that proliferate via retrotransposition, which involves reverse transcription of LINE RNAs. It is anticipated that LINE retrotransposition requires both LINE-encoded proteins and host-encoded proteins. However, identification of the host factors, their roles, and the steps at which they act on retrotransposition are poorly understood because of the lack of an appropriate genetic system to study LINE retrotransposition in a series of mutant hosts.
View Article and Find Full Text PDFThe biosynthesis of female moth sex pheromone blends is controlled by a number of different enzymes, many of which are encoded by members of multigene families. One such multigene family, the acyl-CoA desaturases, is composed of certain genes that function as key players in moth sex pheromone biosynthesis. Although much is known regarding the function of some of these genes, very little is known regarding how novel genes have evolved within this family and how this might impact the establishment of new sex pheromone blends within a species.
View Article and Find Full Text PDFLong interspersed elements (LINEs) are transposable elements that exist in many kinds of eukaryotic genomes, where they have a large effect on genome evolution. There are several thousands to hundreds of thousands of LINE copies in each eukaryotic genome. LINE elements are amplified by a mechanism called retrotransposition, in which a LINE-encoded protein reverse transcribes (copies) its own RNA.
View Article and Find Full Text PDFAutonomous non-long-terminal-repeat retrotransposons (NLRs) proliferate by retrotransposition via coordinated reactions of target DNA cleavage and reverse transcription by a mechanism called target-primed reverse transcription (TPRT). Whereas this mechanism guarantees the covalent attachment of the NLR and its target site at the 3' junction, mechanisms for the joining at the 5' junction have been conjectural. To better understand the retrotransposition pathways, we analyzed target-NLR junctions of zebrafish NLRs with a new method of identifying genomic copies that reside within other transposons, termed "target analysis of nested transposons" (TANT).
View Article and Find Full Text PDFThe eel long interspersed element (LINE) UnaL2 and its partner short interspersed element (SINE) share a conserved 3' tail that is critical for their retrotransposition. The predicted secondary structure of the conserved 3' tail of UnaL2 RNA contains a stem region with a putative internal loop. Deletion of the putative internal loop region abolishes UnaL2 mobilization, indicating that this putative internal loop is required for UnaL2 retrotransposition; the exact role of the putative internal loop in retrotransposition, however, has not been elucidated.
View Article and Find Full Text PDFNihon Shokakibyo Gakkai Zasshi
May 2006
Extra-ampullary duodenal endocrine cell carcinoma is extremely rare. A 65-year-old woman visited our hospital, complaining of epigastralgia, anorexia and vomiting. She was admitted for suspected duodenal or pancreas head tumor by abdominal CT.
View Article and Find Full Text PDFSmaI is a short interspersed element (SINE) of the salmon genome, and is derived from tRNA(Lys). We probed the secondary structure of SmaI SINE RNA by enzymatic cleavage and found that the RNA structure comprises three separate domains. The 5'-terminal region (the 5' domain) forms a tRNA-like cloverleaf structure, whereas the 3'-terminal region (the 3' domain) forms an extended stem-loop.
View Article and Find Full Text PDFLong interspersed elements (LINEs) are a type of retroposon and are widely distributed in most eukaryotic genomes. LINEs are classified into two groups, the stringent type and relaxed type, based on the recognition of the 3' tail of their own RNA by reverse transcriptase (RT) during retrotransposition. Although most LINEs are thought to belong to the stringent type, retrotransposition studies of the stringent type LINEs are relatively limited compared with those of the relaxed type.
View Article and Find Full Text PDFThis is a phase I study to determine the maximum tolerated dose (MTD) and toxicity of a combination of TS-1 and weekly cisplatin (CDDP) in advanced gastric cancer patients. TS-1 was administered orally twice daily after meals, at a standard dose of 80 mg/m2. One course consisted of 21 days' consecutive administration followed by 14 days' rest.
View Article and Find Full Text PDFLong interspersed elements (LINEs) and short interspersed elements (SINEs) are retrotransposons. These elements can mobilize by the "copy-and-paste" mechanism, in which their own RNA is reverse-transcribed into complementary DNA (cDNA). LINEs and SINEs not only are components of eukaryotic genomes but also drivers of genomic evolution.
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