PubMed Health⌕ Search

Biomedical subjects

Hiroyuki Kubo

Publications and source records attributed to Hiroyuki Kubo.

13 recordsLinked to original sources
PubMed2006

Oxidative stress induces ADAM9 protein expression in human prostate cancer cells.

The ADAM (a disintegrin and metalloprotease) family is a group of transmembrane proteins containing cell adhesive and proteolytic functional domains. Microarray analysis detected elevated ADAM9 during the transition of human LNCaP prostate cancer cells from an androgen-dependent to an androgen-independent and metastatic state. Using a prostate tissue array (N = 200), the levels of ADAM9 protein expression were also elevated in malignant as compared with benign prostate tissues. ADAM9 protein expression was found in 43% of benign glands with light staining and 87% of malignant glands with increasing intensity of staining. We found that ADAM9 mRNA and protein expressions were elevated on exposure of human prostate cancer cells to stress conditions such as cell crowding, hypoxia, and hydrogen peroxide. We uncovered an ADAM9-like protein, which is predominantly induced together with the ADAM9 protein by a brief exposure of prostate cancer cells to hydrogen peroxide. Induction of ADAM9 protein in LNCaP or C4-2 cells can be completely abrogated by the administration of an antioxidant, ebselen, or genetic transfer of a hydrogen peroxide degradative enzyme, catalase, suggesting that reactive oxygen species (ROS) are a common mediator. The induction of ADAM9 by stress can be inhibited by both actinomycin D and cycloheximide through increased gene transcription and protein synthesis. In conclusion, intracellular ROS and/or hydrogen peroxide, generated by cell stress, regulate ADAM9 expression. ADAM9 could be responsible for supporting prostate cancer cell survival and progression. By decreasing ADAM9 expression, we observed apoptotic cell death in prostate cancer cells.

ADAM Proteins↗
PubMed2006

Identification of differentially expressed genes in human bladder cancer through genome-wide gene expression profiling.

Large-scale gene expression profiling is an effective strategy for understanding the progression of bladder cancer (BC). The aim of this study was to identify genes that are expressed differently in the course of BC progression and to establish new biomarkers for BC. Specimens from 21 patients with pathologically confirmed superficial (n = 10) or invasive (n = 11) BC and 4 normal bladder samples were studied; samples from 14 of the 21 BC samples were subjected to microarray analysis. The validity of the microarray results was verified by real-time RT-PCR. Of the 136 up-regulated genes we detected, 21 were present in all 14 BCs examined (100%), 44 in 13 (92.9%), and the other 71 in 12 BCs (85.7%). Of 69 down-regulated genes, 25 were found in all 14 BCs (100%), 22 in 13 (92.9%), and the other 22 in 12 BCs (85.7%). Functional annotation revealed that of the up-regulated genes, 36% were involved in metabolism and 14% in transcription and processing; 25% of the down-regulated genes were linked to cell adhesion/surface and 21% to cytoskeleton/cell membrane. Real-time RT-PCR confirmed the microarray results obtained for the 6 most highly up- and the 2 most highly down-regulated genes. Among the 6 most highly up-regulated genes, CKS2 was the only gene with a significantly greater level of up-regulation in invasive than in superficial BC (p = 0.04). To confirm this result, we subjected all 21 BC samples to real-time PCR assay for CKS2. We found a considerable difference between superficial and invasive BC (p = 0.001). Interestingly, there was a considerable difference between the normal bladder and invasive BC (p = 0.001) and less difference between the normal bladder and superficial BC (p = 0.005). We identified several genes as promising candidates for diagnostic biomarkers of human BC and the CKS2 gene not only as a potential biomarker for diagnosing, but also for staging human BC. This is the first report demonstrating that CKS2 expression is strongly correlated with the progression of human BC.

Aged↗
PubMed2005

p16INK4a and p14ARF methylation as a potential biomarker for human bladder cancer.

Promoter hypermethylation is one of the putative mechanisms underlying the inactivation of negative cell-cycle regulators. We examined whether the methylation status of p16(INK4a) and p14(ARF), genes located upstream of the RB and p53 pathway, is a useful biomarker for the staging, clinical outcome, and prognosis of human bladder cancer. Using methylation-specific PCR (MSP), we examined the methylation status of p16(INK4a) and p14(ARF) in 64 samples from 45 bladder cancer patients (34 males, 11 females). In 19 patients with recurrent bladder cancer, we examined paired tissue samples from their primary and recurrent tumors. The methylation status of representative samples was confirmed by bisulfite DNA sequencing analysis. The median follow-up duration was 34.3 months (range 27.0-100.1 months). The methylation rate for p16(INK4a) and p14(ARF) was 17.8% and 31.1%, respectively, in the 45 patients. The incidence of p16(INKa) and p14(ARF) methylation was significantly higher in patients with invasive (>or=pT2) than superficial bladder cancer (pT1) (p=0.006 and p=0.001, respectively). No MSP bands for p16(INK4a) and p14(ARF) were detected in the 8 patients with superficial, non-recurrent tumors. In 19 patients with tumor recurrence, the p16(INK4a) and p14(ARF) methylation status of the primary and recurrent tumors was similar. Of the 22 patients who had undergone cystectomy, 8 (36.4%) manifested p16(INKa) methylation; p16(INK4a) was not methylated in 23 patients without cystectomy (p=0.002). Kaplan-Meier analysis revealed that patients with p14(ARF) methylation had a significantly poorer prognosis than those without (p=0.029). This is the first study indicating that MSP analysis of p16(INK4a) and p14(ARF) genes is a useful biomarker for the pathological stage, clinical outcome, and prognosis of patients with bladder cancer.

Aged↗
PubMed2005

Fluorescent imprinted polymers prepared with 2-acrylamidoquinoline as a signaling monomer.

[structure: see text] A cyclobarbital-selective molecularly imprinted polymer was prepared using a fluorescent functional monomer, 2-acrylamidoquinoline. This monomer was designed to increase in fluorescence intensity upon hydrogen bonding to the cyclobarbital guest. The resultant imprinted polymers exhibited the enhancement of the fluorescence intensity when cyclobarbital was bound. Our results show that this fluorescent responsive imprinting method could be useful in the development of sensors for quantification of nonfluorescent compounds.

Acrylamides↗
PubMed2005

Expression profiling using a tumor-specific cDNA microarray predicts the prognosis of intermediate risk neuroblastomas.

To predict the prognosis of neuroblastoma patients and choose a better therapeutic protocol, we developed a cDNA microarray carrying 5340 genes obtained from primary neuroblastomas and examined 136 tumor samples. We made a probabilistic output statistical classifier that provided a high accuracy in prognosis prediction (89% at 5 years) and a highly reliable method to validate it. Kaplan-Meier analysis indicated that the patients in an intermediate group defined by existing markers are divided by microarray into two further groups with 5 year survivals for 36% and 89% of patients (p < 10(-4)), i.e., with unfavorably and favorably predicted neuroblastomas, respectively. According to these results, we developed a gene subset chip for a clinical tool, for which our classifier exhibited 88% prediction accuracy.

Algorithms↗
PubMed2003

Phase I dose escalation clinical trial of adenovirus vector carrying osteocalcin promoter-driven herpes simplex virus thymidine kinase in localized and metastatic hormone-refractory prostate cancer.

Osteocalcin (OC), a major noncollagenous bone matrix protein, is expressed prevalently in prostate cancer epithelial cells, adjacent fibromuscular stromal cells, and osteoblasts in locally recurrent prostate cancer and prostate cancer bone metastasis [Matsubara, S., Wada, Y., Gardner, T.A., Egawa, M., Park, M.S., Hsieh, C.L., Zhau, H.E., Kao, C., Kamidono, S., Gillenwater, J.Y., and Chung, L.W. (2001). Cancer Res. 61, 6012-6019]. We constructed an adenovirus vector carrying osteocalcin promoter-driven herpes simplex virus thymidine kinase (Ad-OC-hsv-TK) to cotarget prostate cancer cells and their surrounding stromal cells. A phase I dose escalation clinical trial of the intralesional administration of Ad-OC-hsv-TK followed by oral valacyclovir was conducted at the University of Virginia (Charlottesville, VA) in 11 men with localized recurrent and metastatic hormone-refractory prostate cancer (2 local recurrent, 5 osseous metastasis, and 4 lymph node metastasis) in order to determine the usefulness of this vector for the palliation of androgen-independent prostate cancer metastasis. This is the first clinical trial in which therapeutic adenoviruses are injected directly into prostate cancer lymph node and bone metastasis. Results show that (1). all patients tolerated this therapy with no serious adverse events; (2). local cell death was observed in treated lesions in seven patients (63.6%) as assessed by TUNEL assay, and histomorphological change (mediation of fibrosis) was detected in all posttreated specimens; (3). one patient showed stabilization of the treated lesion for 317 days with no alternative therapy. Of the two patients who complained of tumor-associated symptoms before the treatment, one patient with bone pain had resolution of pain, although significant remission of treated lesions was not observed by image examination; (4). CD8-positive T cells were predominant compared with CD4-positive T cells, B cells (L26 positive), and natural killer cells (CD56 positive) in posttreated tissue specimens; (5). levels of HSV TK gene transduction correlated well with coxsackie-adenovirus receptor expression but less well with the titers of adenovirus injected; and (6). intrinsic OC expression and the efficiency of HSV TK gene transduction affected the levels of HSV TK protein expression in clinical specimens. Our data suggest that this form of gene therapy requires further development for the treatment of androgen-independent prostate cancer metastasis although histopathological and immunohistochemical evidence of apoptosis was observed in the specimens treated. Further studies including the development of viral delivery will enhance the efficacy of Ad-OC-hsv-TK.

Adenoviridae↗
PubMed2003

Design and feasibility assessment of topically applied drug formulations for electroporation.

Few studies have been reported on the design of topical formulations consisting of electrodes and active drugs for electroporation as a means to increase skin permeability of the drugs, although many studies were reported for the effect of this physical means using aqueous drug solutions. We, therefore, designed a prototypic reservoir and matrix topical formulations that are suitable for electroporation in the present study. Plate-plate Ag electrodes and sodium diclofenac were used as model electrodes and the drug, respectively. The in vitro skin permeations of the drug obtained from the reservoir and matrix formulations were slightly higher than that from an aqueous suspension. This may be due to slightly higher electric field in the skin barrier for the presently designed formulations than that for the aqueous suspension. The present feasibility test suggests that these reservoirs and matrix formulations are useful prototypic topical formulations for electroporation application to improve the drug permeability through skin.

Administration, Topical↗
PubMed2002

Synthesis of alpha-lactosyl-(1-->3)-L-glycero-alpha-D-manno-heptopyranoside, a partial oligosaccharide structure expressed within the lipooligosaccharide produced by Neisseria gonorrhoeae strain 15253.

The glycosyl donor, hepta-O-benzyl-beta-lactosyl trichloroacetimidate (4) was prepared by treating hepta-O-benzyl-lactose with trichloroacetonitrile in the presence of potassium carbonate. The acceptor, methyl 2-O-benzyl-4,6-O-benzylidene-7,8-dideoxy-alpha-D-manno-oct-7-enopyranoside (8) was synthesized by hydrolysis of a 3,4-butane diacetal of methyl L-glycero-alpha-D-manno-oct-enopyranoside and subsequent benzylidenation. Glycosidation of the donor 4 with the acceptor 8 in 1,4-dioxane using Me(3)SiOTf as a promoter for 1 h at room temperature gave methyl (2,3,4,6-tetra-O-benzyl-beta-D-galactopyranosyl)-(1-->4)-(2,3,6-tri-O-benzyl-alpha-D-glucopyranosyl)-(1-->3)-2-O-benzyl-4,6-O-benzylidene-7,8-dideoxy-alpha-D-manno-oct-7-enopyranoside (9) as a major product (59%). The oct-enopyranoside moiety of the trisaccharide 9 was converted to a heptopyranoside (80%) by oxidative cleavage with OsO(4)-NaIO(4) and subsequent reduction. Hydrogenolysis of the resulting trisaccharide and subsequent acetylation gave the peracetate of alpha-lactosyl-(1-->3)-Hep. Deacetylation of the peracetate afforded the title trisaccharide.

Epitopes↗
PubMed2002

Primary malignant melanoma of the male urethra.

We report a case of primary malignant melanoma of the male urethra in a patient whose penile shaft was successfully preserved, but who proceeded to acute renal failure (ARF) after interferon (IFN)-beta adjuvant immunotherapy. Primary malignant melanoma of the male urethra is rare and usually shows highly malignant potential. Therefore, urologists must often perform phallectomy, which impacts on the patient both sexually and mentally. A 64-year-old man presented at Saiseikai Sendai Hospital with asymptomatic gross hematuria and was diagnosed as distal urethral tumor. We predicted the highly malignant potential of this tumor from the urethroscopic finding and from urinary cytological examination. We did not select trans-urethral resection (TUR), but selected partial urethrectomy. This patient proceeded to ARF 1 month after natural IFN-beta treatment as an adjuvant immunotherapy. As IFN-beta rarely induces the delayed renal failure, urologists should be aware of renal dysfunction after IFN-beta therapy for the treatment of malignant melanoma.

Acute Kidney Injury↗
PubMed2002

Reversal of P-glycoprotein-mediated paclitaxel resistance by new synthetic isoprenoids in human bladder cancer cell line.

We isolated a paclitaxel-resistant cell line (KK47/TX30) from a human bladder cancer cell line (KK47/WT) in order to investigate the mechanism of and reversal agents for paclitaxel resistance. KK47/TX30 cells exhibited 700-fold resistance to paclitaxel and cross-resistance to vinca alkaloids and topoisomerase II inhibitors. Tubulin polymerization assay showed no significant difference in the ratio of polymerized alpha- and beta-tubulin between KK47/WT and KK47/TX30 cells. Western blot analysis demonstrated overexpression of P-glycoprotein (P-gp) and lung resistance-related protein (LRP) in KK47/TX30 cells. Drug accumulation and efflux studies showed that the decreased paclitaxel accumulation in KK47/TX30 cells was due to enhanced paclitaxel efflux. Cell survival assay revealed that verapamil and cepharanthine, conventional P-gp modulators, could completely overcome paclitaxel resistance. To investigate whether new synthetic isoprenoids could overcome paclitaxel resistance, we synthesized 31 isoprenoids based on the structure of N-solanesyl-N,N'-bis(3,4-dimethoxybenzyl)ethylenediamine (SDB), which could reverse multidrug resistance (MDR), as shown previously. Among those examined, trans-N,N'-bis(3,4-dimethoxybenzyl)-N-solanesyl-1,2-diaminocyclohexane (N-5228) could completely reverse paclitaxel resistance in KK47/TX30 cells. N-5228 inhibited photoaffinity labeling of P-gp by [(3)H]azidopine, suggesting that N-5228 could bind to P-gp directly and could be a substrate of P-gp. Next, we investigated structural features of these 31 isoprenoids in order to determine the structural requirements for the reversal of P-gp-mediated paclitaxel resistance, suggesting that the following structural features are important for overcoming paclitaxel resistance: (1) a basic structure of 8 to 10 isoprene units, (2) a cyclohexane ring or benzene ring within the framework, (3) two cationic sites in close proximity to each other, and (4) a benzyl group with 3,4-dimethoxy functionalities, which have moderate electron-donating ability. These findings may provide valuable information for the development of P-gp-mediated MDR-reversing agents.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMedDate not supplied

Evaluation of genetic mutations of tumor suppresser genes in colorectal cancer patients.

BACKGROUND/AIMS: The mutation of tumor suppresser genes of colorectal cancer was evaluated to clarify its significance in the clinical management of colorectal cancer patients. METHODOLOGY: Polymerase chain reaction amplification was performed to investigate the loss of heterozygosity (LOH) of the DCC (deleted-in-colorectal-carcinoma) gene and p53 gene in 76 colorectal cancers. RESULTS: Thirty-five of 76 tumors showed LOH at the p53 locus. LOH at the DCC locus was observed in 30 of 76 tumors. Tumors with DCC LOH had a significantly higher rate of p53 LOH. DCC LOH was associated with both liver metastasis and lymph node metastasis. Moreover, younger patients and patients with a well-differentiated adenocarcinoma had a higher risk of liver and lymph node metastasis when the tumor had DCC LOH. The association between liver or lymph node metastasis and clinicopathological factors was stronger in tumors with smaller size and negative serosal invasion. CONCLUSIONS: The careful exploration of the liver and regional lymph nodes is advocated when the tumor has a DCC alteration, even at an early stage of the disease and especially in younger patients and patients with a well-differentiated carcinoma. The assessment of DCC LOH may be useful for selecting patients for extensive surgical intervention or adjuvant chemotherapy.

Adult↗