Biomedical subjects

Daisuke Yamada

Publications and source records attributed to Daisuke Yamada.

16 recordsLinked to original sources

PubMed2006

Effect of beta-lactotensin on acute stress and fear memory.

beta-Lactotensin (beta-LT) is a bioactive peptide derived from bovine milk beta-lactoglobulin and is a natural ligand for neurotensin receptors. We examined the effect of beta-LT on restraint stress and fear memory in mice. Mice subjected to acute restraint stress exhibited a decreased number of head-dips and increased head-dip latency compared to non-stressed controls in the hole-board test, reflecting increased stress-induced behaviors. However, prior administration of beta-LT improved the behaviors caused by stress. The anti-stress effect of beta-LT was blocked by levocabastine, a neurotensin receptor subtype 2 (NTR2) antagonist. In the fear-conditioning test, the duration of freezing responses by cued fear conditioning was significantly reduced in mice administered beta-LT compared with control mice. These results suggest that beta-LT has an anti-stress effect and promotes the extinction of fear memory, which may be mediated by NTR2.

Animals↗

PubMed2006

Overexpression of c-met in the early stage of pancreatic carcinogenesis; altered expression is not sufficient for progression from chronic pancreatitis to pancreatic cancer.

AIM: To investigate c-met expression during early pancreatic carcinogenesis. METHODS: We used 46 bulk tissues and 36 micro-dissected samples, including normal pancreas, chronic pancreatitis, and pancreatic cancer, for quantitative real-time reverse transcription-polymerase chain reaction. RESULTS: In bulk tissue analyses, pancreatic cancer tissues expressed significantly higher levels of c-met than did chronic pancreatitis and normal pancreas tissues. c-met levels did not differ between chronic pancreatitis and normal pancreas tissues. In microdissection-based analyses, c-met was expressed at higher levels in microdissected pancreatic cancer cells and pancreatitis-affected epithelial cells than in normal ductal epithelial cells (both, P < 0.01). Interestingly, pancreatitis-affected epithelial cells expressed levels of c-met similar to those of pancreatic cancer cells. CONCLUSION: Overexpression of c-met occurs during the early stage of pancreatic carcinogenesis, and a single alteration of c-met expression is not sufficient for progression of chronic pancreatitis-affected epithelial cells to pancreatic cancer cells.

Biomarkers, Tumor↗

PubMed2006

Hypermethylation of the TSLC1/IGSF4 promoter is associated with tobacco smoking and a poor prognosis in primary nonsmall cell lung carcinoma.

BACKGROUND: The tumor suppressor gene TSLC1/IGSF4 on chromosomal region 11q23 is frequently inactivated by promoter methylation in various cancers, including nonsmall cell lung carcinoma (NSCLC). Several studies have demonstrated that the hypermethylation of the CpG islands of genes, including tumor suppressors, is associated with exposure to tobacco smoke. The purpose of this study was to investigate the possible association of TSLC1/IGSF4 methylation with tobacco smoking as well as with the clinical characteristics of tumors using a large number of primary NSCLC. METHODS: The promoter methylation of TSLC1/IGSF4 was analyzed in 103 primary NSCLC. TSLC1/IGSF4 expression was examined by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry, whereas its methylation status was determined by bisulfite single-strand conformation polymorphism (SSCP) coupled with bisulfite sequencing. RESULTS: The TSLC1/IGSF4 promoter was methylated in 45 (44%) of 103 primary NSCLC. Methylation was observed in all histologic subtypes of NSCLC, including adenocarcinoma (29 of 68, 43%), squamous cell carcinoma (14 of 26, 54%), adenosquamous carcinoma (1 of 2, 50%), and large cell carcinoma (1 of 7, 14%). The incidence of methylation in tumors was significantly higher in male patients than in female patients (P = .027). The TSLC1/IGSF4 methylation was preferentially observed in heavy smokers (smoking index > or = 800) (P = .0054). Furthermore, in smokers the methylation was significantly associated with pack-years smoked (P = .034) and cigarettes per day (P = .021). The TSLC1/IGSF4 methylation was also significantly associated with a shorter disease-free survival (P = .049), providing an independent prognostic factor (P = .038) in adenocarcinoma patients. CONCLUSIONS: TSLC1/IGSF4 methylation is associated with tobacco smoking and could be an indicator of poor prognosis.

Aged↗

PubMed2006

Quantitative analysis of human telomerase reverse transcriptase in pancreatic cancer.

Although telomerase activity is a promising diagnostic marker, clinical introduction of this marker for cancer diagnosis is still problematic due to the lack of means of evaluating sample quality. Human telomerase reverse transcriptase (hTERT), one of the subunits of telomerase, is also a promising diagnostic marker. In the present study, we did large-scale analysis of 88 pancreatic juice samples to determine the feasibility of quantitative analysis of hTERT mRNA for diagnosis of pancreatic cancer. We found significant differences in hTERT expression among carcinoma-derived, intraductal papillary mucinous neoplasm (IPMN)-derived, and chronic pancreatitis-derived juice samples. Results showed that quantitative analyses of hTERT mRNAs are more useful in discriminating carcinoma from IPMN than from chronic pancreatitis. When the specificity was set at 100%, the sensitivity for differentiation between carcinoma and IPMN was 43.5%, whereas the sensitivity of cytologic examination was 22.0%. There were significant differences in hTERT expression among carcinoma cells, IPMN cells, and normal ductal cells isolated from pancreatic tissues by microdissection. Lymphocytes and hyperplastic epithelial cells isolated from tissues with the histologic appearance of pancreatitis showed various expression levels of hTERT. Our results suggest that quantitative analysis of hTERT mRNA in pancreatic juice is advantageous over cytologic analysis for differentiation between carcinoma and IPMN but probably not for differentiation between carcinoma and chronic pancreatitis.

DNA-Binding Proteins↗

PubMed2006

Promoter hypermethylation of the potential tumor suppressor DAL-1/4.1B gene in renal clear cell carcinoma.

Renal clear cell carcinoma (RCCC) is a malignant tumor with poor prognosis caused by the high incidence of metastasis to distal organs. Although metastatic RCCC cells frequently show aberrant cytoskeletal organization, the underlying mechanism has not been elucidated. DAL-1/4.1B is an actin-binding protein implicated in the cytoskeleton-associated processes, while its inactivation is frequently observed in lung and breast cancers and meningiomas, suggesting that 4.1B is a potential tumor suppressor. We studied a possible involvement of 4.1B in RCCCs and evaluated it as a clinical indicator. 4.1B protein was detected in the proximal convoluted tubules of human kidney, the presumed cell of origin of RCCC. On the other hand, loss or marked reduction of its expression was observed in 10 of 19 (53%) renal cell carcinoma (RCC) cells and 12 of 19 (63%) surgically resected RCCC by reverse transcription-PCR. Bisulfite sequencing or bisulfite SSCP analyses revealed that the 4.1B promoter was methylated in 9 of 19 (47%) RCC cells and 25 of 55 (45%) surgically resected RCCC, and inversely correlated with 4.1B expression (p < 0.0001). Aberrant methylation appeared to be a relatively early event because more than 40% of the tumors with pT1a showed hypermethylation. Furthermore, 4.1B methylation correlated with a nuclear grade (p = 0.017) and a recurrence-free survival (p = 0.0036) and provided an independent prognostic factor (p = 0.038, relative risk 10.5). These results indicate that the promoter methylation of the 4.1B is one of the most frequent epigenetic alterations in RCCC and could predict the metastatic recurrence of the surgically resected RCCC.

Aged↗

PubMed2006

Quantitative analysis of MUC1 and MUC5AC mRNA in pancreatic juice for preoperative diagnosis of pancreatic cancer.

Pancreatic juice is a promising type of diagnostic sample for pancreatic cancer, and members of the mucin (MUC) family are diagnostic candidates. To evaluate the utility of MUC family members as diagnostic markers, we measured MUC mRNA expression in pancreatic tissues and pancreatic juice obtained from patients with different pancreatic diseases as well as in pancreatic cancer cell lines by real-time PCR. Furthermore, to support the possibility of early diagnosis by quantification of MUC1 and MUC5AC, immunohistochemistry and microdissection-based quantitative analysis of mRNA were carried out. There was no significant correlation between MUC1 and MUC5AC expression in cell lines. When beta-actin was used as a reference gene, median MUC1 and MUC5AC mRNA expression levels were remarkably greater in tumoral tissues than in non-tumoral tissues, but median MUC4 and MUC6 mRNA expression levels were not. Receiver operating characteristic curve analysis showed that quantitative analysis of MUC1 and MUC5AC mRNA in pancreatic juice is better diagnostic modality than that of MUC4 and MUC6 mRNA. Immunohistochemistry showed that MUC1 and MUC5AC were highly expressed in invasive ductal carcinomas (IDC) and moderately expressed in high-grade pancreatic intraepithelial neoplasia (PanIN); no staining was observed in normal ducts. Analysis of cells isolated by microdissection showed stepwise upregulation of MUC1 and MUC5AC in the development of high-grade PanIN to IDC. Our results suggest that MUC1 and MUC5AC are upregulated stepwise in pancreatic carcinogenesis and that quantitative assessment of MUC1 and MUC5AC mRNA in pancreatic juice has high potential for preoperative diagnosis of pancreatic cancer.

Biomarkers, Tumor↗

PubMed2006

Born to bind: the BTB protein-protein interaction domain.

The BTB domain is a protein-protein interaction motif that is found throughout eukaryotes. It determines a unique tri-dimensional fold with a large interaction surface. The exposed residues are highly variable and can permit dimerization and oligomerization, as well as interaction with a number of other proteins. BTB-containing proteins are numerous and control cellular processes that range from actin dynamics to cell-cycle regulation. Here, we review findings in the field of transcriptional regulation to illustrate how the high variability of the BTB has allowed related transcription factors to evolve different functional abilities. We then report how recent work has showed that, in spite of their high sequence divergence and apparently unrelated functions, many BTB-containing proteins have at least one shared role: the recruitment of degradation targets to E3 ubiquitin ligase complexes. Taken together, these findings illustrate diverse and convergent functions of a versatile protein-protein interaction domain.

Amino Acid Sequence↗

PubMed2006

Strategy for prevention of local recurrence of pancreatic cancer after pancreatectomy: antitumor effect of gemcitabine mixed with fibrin glue in an orthotopic nude mouse model.

BACKGROUND: Pancreatic cancer frequently recurs after operative treatment, resulting in a poor prognosis. Inhibition of proliferation of residual cancer cells is important for improved survival of patients with pancreatic cancer. Fibrin glue (FG) is a biocompatible, adherent hemostat that can deliver high concentrations of anticancer drugs to residual cancer cells. The aim of this study was to evaluate the local antitumor effect of a mixture of gemcitabine (GEM) and FG on pancreatic cancer cells implanted orthotopically in nude mice. METHODS: SUIT-2 human pancreatic cells were injected into the tail of the pancreas of nude mice. Seven days later, groups of mice were treated with 80 mg/kg GEM mixed with 0.5 mL fibrin glue (GEM + FG), 0.5 mL FG alone (FG), single intraperitoneal (i.p.) injection of 80 mg/kg GEM (GEM1), i.p. injection of 80 mg/kg GEM weekly for 3 weeks (GEM1,2,3), GEM + FG followed by weekly GEM injections for 2 weeks (GEM + FG + GEM2,3), or i.p. injection of PBS weekly for 3 weeks (controls). RESULTS: Twenty-eight days after cell injections, tumor volumes of groups treated with GEM + FG + GEM2,3, GEM1,2,3, GEM + FG, GEM1, and FG were decreased by 84%, 70%, 62%, 37%, and 10%, respectively, compared to that of control mice. GEM + FG + GEM2,3 had the strongest anticancer effect compared to all other groups (P < .05). Additionally, GEM + FG showed a more potent antitumor effect compared to GEM1 (P < .05). Survival of mice treated with GEM + FG + GEM2,3 was longer than that of mice in all other groups (P < .05). CONCLUSIONS: A mixture of GEM and FG was effective in inhibiting the growth of orthotopically implanted pancreatic neoplasms in nude mice. This procedure may be useful clinically to prevent the local recurrence of pancreatic cancer after pancreatectomy.

Animals↗

PubMed2006

A family of human zinc finger proteins that bind methylated DNA and repress transcription.

In vertebrates, densely methylated DNA is associated with inactive transcription. Actors in this process include proteins of the MBD family that can recognize methylated CpGs and repress transcription. Kaiso, a structurally unrelated protein, has also been shown to bind methylated CGCGs through its three Krüppel-like C2H2 zinc fingers. The human genome contains two uncharacterized proteins, ZBTB4 and ZBTB38, that contain Kaiso-like zinc fingers. We report that ZBTB4 and ZBTB38 bind methylated DNA in vitro and in vivo. Unlike Kaiso, they can bind single methylated CpGs. When transfected in mouse cells, the proteins colocalize with foci of heavily methylated satellite DNA and become delocalized upon loss of DNA methylation. Chromatin immunoprecipitation suggests that both of these proteins specifically bind to the methylated allele of the H19/Igf2 differentially methylated region. ZBTB4 and ZBTB38 repress the transcription of methylated templates in transfection assays. The two genes have distinct tissue-specific expression patterns, but both are highly expressed in the brain. Our results reveal the existence of a family of Kaiso-like proteins that bind methylated CpGs. Like proteins of the MBD family, they are able to repress transcription in a methyl-dependent manner, yet their tissue-specific expression pattern suggests nonoverlapping functions.

Amino Acid Sequence↗

PubMed2006

Disruption of spermatogenic cell adhesion and male infertility in mice lacking TSLC1/IGSF4, an immunoglobulin superfamily cell adhesion molecule.

TSLC1/IGSF4, an immunoglobulin superfamily molecule, is predominantly expressed in the brain, lungs, and testes and plays important roles in epithelial cell adhesion, cancer invasion, and synapse formation. We generated Tslc1/Igsf4-deficient mice by disrupting exon 1 of the gene and found that Tslc1(-/-) mice were born with the expected Mendelian ratio but that Tslc1(-/-) male mice were infertile. In 11-week-old adult Tslc1(-/-) mice, the weight of a testis was 88% that in Tslc1(+/+) mice, and the number of sperm in the semen was approximately 0.01% that in Tslc1(+/+) mice. Histological analysis revealed that the round spermatids and the pachytene spermatocytes failed to attach to the Sertoli cells in the seminiferous tubules and sloughed off into the lumen with apoptosis in the Tslc1(-/-) mice. On the other hand, the spermatogonia and the interstitial cells, including Leydig cells, were essentially unaffected. In the Tslc1(+/+) mice, TSLC1/IGSF4 expression was observed in the spermatogenic cells from the intermediate spermatogonia to the early pachytene spermatocytes and from spermatids at step 7 or later. These findings suggest that TSLC1/IGSF4 expression is indispensable for the adhesion of spermatocytes and spermatids to Sertoli cells and for their normal differentiation into mature spermatozoa.

Animals↗

PubMed2005

Promoter methylation of DAL-1/4.1B predicts poor prognosis in non-small cell lung cancer.

PURPOSE: DAL-1/4.1B is an actin-binding protein originally identified as a molecule whose expression is down-regulated in lung adenocarcinoma. We have previously shown that a lung tumor suppressor, TSLC1, associates with DAL-1, suggesting that both proteins act in the same cascade. The purpose of this study is to understand the molecular mechanisms and clinical significance of DAL-1 inactivation in lung cancer. EXPERIMENTAL DESIGN: We studied aberration of the DAL-1 in 103 primary non-small cell lung cancers (NSCLC) and 18 lung cancer cells. Expression and allelic and methylation status of DAL-1 was examined by reverse transcription-PCR, microsatellite analysis, and bisulfite sequencing or bisulfite single-strand conformational polymorphism, respectively. RESULTS: Loss of DAL-1 expression was strongly correlated with promoter methylation in lung cancer cells, whereas DAL-1 expression was restored by a demethylating agent, 5-aza-2'-deoxycytidine. The DAL-1 promoter was methylated in 59 (57%) primary NSCLC tumors, 37% of which were associated with loss of heterozygosity around the DAL-1 on chromosomal region 18p11.3. In squamous cell carcinomas, DAL-1 methylation was observed in 9 of 10 tumors at stage I, whereas the incidence of methylation gradually increased in adenocarcinomas as they progressed [13 of 36 (36%), 4 of 12 (33%), 14 of 17 (82%), and 3 of 3 (100%) tumors at stages I, II, III, and IV, respectively; P = 0.0026]. Furthermore, in adenocarcinomas, disease-free survival and overall survival were significantly shorter in patients with tumors harboring the methylated DAL-1 (P = 0.0011 and P = 0.045, respectively). CONCLUSIONS: DAL-1 methylation is involved in the development and progression of NSCLC and provides an indicator for poor prognosis.

Aged↗

PubMed2004

Three-component coupling based on the "cation pool" method.

Sequential one-pot three-component coupling reactions have been developed based on the "cation pool" method. An N-acyliminium ion generated by the "cation pool" method adds to an electron-rich carbon-carbon double bond, such as enamine derivatives and vinyl sulfides, to form the second "cation pool". The addition of nucleophiles such as allylsilanes, enol silyl ethers, Grignard reagents, and organoaluminum compounds led to the formation of the corresponding three-component coupling products.

Journal Article↗

PubMed2004

Comprehensive search for chicken W chromosome-linked genes expressed in early female embryos from the female-minus-male subtracted cDNA macroarray.

In order to seek chicken W chromosome-linked genes expressed significantly earlier than the time of gonadal differentiation, female-minus-male-subtracted cDNA macroarrays were prepared from day 2 (Hamburger-Hamilton stages 12-13), day 3 (stages 19-20) and day 4 (stages 24-25) embryos. From a total of 15-744 macroarrayed cDNA clones, 610 clones exhibiting significantly female-specific expression were selected. When each one of the 610 cDNA clones was used as a probe in Southern blot hybridization with male or female chicken genomic DNA, 62 clones, grouped into eight (A-H) types according to their patterns of hybridization, were considered to be derived from W chromosome-linked genes. When representative cDNA clones in each type were sequenced, clones derived from two known W-linked genes; SPIN-W and ATP5A1W , and from two hitherto unknown W-linked genes, represented by 2d-2D9 and 2d-2F9 clones, were identified and their localizations on the W chromosome were confirmed by fluorescence in-situ hybridization. The 2d-2D9 sequence has no significant homology with other genes in databases but 2d-2F9 has a region which shows partial homology to the consensus sequence of the AAA ATPase superfamily. Both 2d-2D9 and 2d-2F9 sequences are found in contigs of undetermined chromosome-linkage in the Draft Chicken Genome Sequence.

Animals↗

PubMed2003

Retroperitoneoscopic nephropexy for symptomatic nephroptosis.

PURPOSE: Recently, laparoscopic nephropexy has been performed using a transperitoneal approach. We evaluated the efficacy of a retroperitoneoscopic technique for symptomatic nephroptosis. PATIENTS AND METHODS: Three men and two women with right nephroptosis underwent retroperitoneal laparoscopic nephropexy. Their symptoms were right flank pain, gross hematuria, or both. The mean body mass index was 18.7. Surgery consisted of complete dissection of the kidney, after which three sutures were placed between the renal capsule at the posterior lateral edge and the psoas or quadratus lumborum muscle. Silk sutures were used in all five patients. RESULTS: Retroperitoneoscopic nephropexy was successful with no intraoperative complications. The mean operative time was 167 minutes, and the mean estimated blood loss was <10 mL in all five patients. The mean convalescence period was 19.6 days. A postoperative urogram with the patients both supine and erect revealed an improvement in renal function, decreased displacement of the kidney (less than one vertebral body), or both. All patients were satisfied with the clinical outcome during an average of 18 months of follow-up. CONCLUSIONS: Retroperitoneoscopic nephropexy is feasible for patients with symptomatic nephroptosis. We recommend nonabsorbable materials such as silk for fixation of the kidney to the psoas or quadratus lumborum muscle.

Adult↗

PubMed2002

[Pulmonary embolism (PE) associated with urological surgery and angiography].

As a result of the Westernization of life style in Japan, the incidence of pulmonary embolism (PE) has been increasing, mainly after surgery and vessel catheterization. We encountered 4 cases of PE associated with urological surgery and angiography during the 3 and half years since 1995; one occurred after nephrouretectomy, one after TUR-P, and two after abdominal angiography. Three patients recovered from PE, but the other is still on a respirator. As risk factors of PE, 3 patients were over 60 years old, one was obese, two had hypertension, and one had atrial fibrillation (Af). Three patients were given tranexamic acid (AMCA). Prophylactic procedures against PE, such as intermittent compression devices for the lower extremities and low-molecule heparinization, are recommended for high-risk patients. AMCA should be used with care in patients who undergo surgery and angiography.

Aged↗

PubMed2002

[The analysis of thymidine phosphorylase examined by ELISA in bladder cancer].

PURPOSE: Some reports suggest that the high level expression of thymidine phosphorylase (TP), which is known as one of angiogenic factors, is related to high malignancy and also poor prognosis in the field of gastrointestinal cancer. So the authors investigated the expression of TP in bladder cancer. MATERIALS AND METHODS: The expression of TP in cancer tissues and normal tissues, which were obtained during transurethral resection of the tumor of 66 patients with initial primary bladder cancer, was examined by enzyme-linked immunosorbent assay (ELISA). And relationship of the TP expression and clinicopathologic factors was investigated. RESULTS: The level of TP expression was significantly high in cancer tissues compared with normal tissues (P < 0.0001). About the level of TP expression of cancer tissues, there was a significant difference between G1 and G3 in grade (P = 0.0099), Ta and T2 or greater (P = 0.0059), Ta, T1 and T2 or greater (P = 0.0157) in T stage, papillary and non-papillary in surface form (P = 0.0056), pedunculated and sessile in tumor shape (P = 0.0458), and 1 cm or under and 3 cm or greater in size (P = 0.0267). The level was higher in latter, respectively. About the level of TP expression of normal tissues, the level was significantly higher in the cases with sessile tumor than the cases with pedunculated tumor (P = 0.0078). CONCLUSION: There is correlation between the level of TP expression of cancer tissues and their grade of malignancy, so we can expect that the level of TP expression of cancer tissues will be a prognostic factor. And what does it mean in the fact that the level of TP expression of normal tissues in patients with sessile tumor is higher? It should be clear after accumulation of the cases and collecting the episodes in the follow-up period.

Carcinoma, Transitional Cell↗