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Motoshi Kawahara

Publications and source records attributed to Motoshi Kawahara.

12 recordsLinked to original sources
PubMed2006

Smoking influences aberrant CpG hypermethylation of multiple genes in human prostate carcinoma.

BACKGROUND: Aberrant CpG methylation profiles of gene promoters and their correlation with advanced pathologic features have been well investigated in prostate carcinoma (PC). Several case-control and prospective studies have revealed a positive association between current smoking and PC. The authors hypothesized that smoking influences both progression and prognosis of PC through CpG hypermethylation of related genes. METHODS: A total of 164 PC patients (52 current, 30 former, and 82 never smokers) and 69 benign prostatic hyperplasia (BPH) patients were examined by methylation-specific PCR (MSP) for 3 genes: adenomatous polyposis coli (APC), glutathione S-transferase pi (GSTP1), and multidrug resistance one (MDR1). The methylation status of representative samples was confirmed by bisulfite DNA sequencing analysis. The newly defined methylation score (M-score) of each sample is the sum of the corresponding log hazard ratio (HR) coefficients derived from multivariate logistic regression analysis for pathology (BPH vs. PC), and was related to clinical and pathologic outcome including smoking status. RESULTS: The M-score was significantly higher in the current smokers than in never smokers (P = 0.008). Spearman rank correlation test demonstrated a significant correlation between pack-years smoked and M-score in PCs (P = 0.039). Significant correlation of the M-score methylation was observed with high pT category (P < 0.001), high Gleason sum (P < 0.001), high preoperative prostate-specific antigen (PSA) (P = 0.041), and advanced pathologic features. In addition, Gleason sum was significantly associated with PSA failure-free probability as a poor outcome (P = 0.020). CONCLUSIONS: This is the first study to demonstrate significant correlation of the methylation status of multigenes with smoking status in PC. Smoking status may influence both progression and prognosis of PC through CpG hypermethylation of related genes.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2006

[Antimicrobial susceptibilities of organisms isolated from patients with urinary tract infections in 2002].

Using the agar dilution method, the antibacterial activity of 18 antibiotics inclusive of 4 carbapenems were investigated against 101 strains of urinary pathogens isolated from patients with urinary tract infections who visited the Department of Urology at Kagoshima University Hospital, between January and December 2002. 4 strains of Staphylococcus aureus, 3 strains of Staphylococcus spp. (exclusive of S. aureus), 14 strains of Enterococcus faecalis, 3 strains of Enterococcus spp. (exclusive of E. faecalis), 41 strains of Escherichia coli, 21 strains of Enterobacteriaceae (exclusive of E. coli), 12 strains of Pseudomonas aeruginosa and 3 strains of glucose-nonfermentative Gram-negative rods (exclusive of P. aeruginosa) were examined. 1. Against clinical isolates of Gram-positive bacteria, vancomycin and teicoplanin were active. Additionally, arbekacin was active against S. aureus clinical isolates and ampicillin was active against E. faecalis clinical isolates. Carbapenems were active against clinical isolates of Gram-positive bacteria, except for multi-drug resistant strains of Gram-positive bacteria, such as methicillin-resistant S. aureus. 2. As for clinical isolates of Gram-negative bacteria, meropenem was most active against Enterobacteriaceae among 13 antibiotics tested. Against P. aeruginosa clinical isolates, MIC90 of meropenem was the lowest among 13 antibiotics tested. In addition, resistant rate of meropenem and biapenem against P. aeruginosa clinical isolates was lower than those of the other carbapenems tested. 3. As main urinary pathogens showed no remarkable increase in resistance to carbapenems, it can be stated that carbapenems retain their position as the drug of first choice for severe infection.

Anti-Bacterial Agents↗
PubMed2006

Molecular basis for the involvement of thymidine phosphorylase in cancer invasion.

Thymidine phosphorylase (TP), also known as platelet-derived endothelial cell growth factor (PD-ECGF), has been implicated in bladder cancer angiogenesis and invasion. However, the molecular basis of its role in invasion remains unclear. We investigated the expression of TP and 10 invasion-related genes in bladder cancers from 72 randomly selected patients by real-time two-step RT-PCR assay. We found that the expression levels of TP, MMP-9, uPA, and MMP-2 were significantly higher in invasive tumors than those in superficial tumors. Also, the expression level of TP significantly correlated with that of uPA, MMP-1, MMP-9, PAI-1 and VEGF. KK47/TP cells, bladder cancer cells that overexpress TP, had a higher expression of MMP-7 and MMP-9 than KK/CV cells that express lower level of TP in hypoxic condition. PC/TP cells, prostate cancer cells that overexpress TP, also had a higher expression of MMP-1 and MMP-7 than PC/CV cells that express no detectable TP. Taken together these data indicate that TP enhances the invasion of tumor cells through the induction of invasion-related genes.

Cell Line, Tumor↗
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

Multigene methylation analysis for detection and staging of prostate cancer.

PURPOSE: Aberrant gene promoter methylation profiles have been well-studied in human prostate cancer. Therefore, we rationalize that multigene methylation analysis could be useful as a diagnostic biomarker. We hypothesize that a new method of multigene methylation analysis could be a good diagnostic and staging biomarker for prostate cancer. EXPERIMENTAL DESIGN: To test our hypothesis, prostate cancer samples (170) and benign prostatic hyperplasia samples (69) were examined by methylation-specific PCR for three genes: adenomatous polyposis coli (APC), glutathione S-transferase pi (GSTP1), and multidrug resistance 1 (MDR1). The methylation status of representative samples was confirmed by bisulfite DNA sequencing analysis. We further investigated whether methylation score (M score) can be used as a diagnostic and staging biomarker for prostate cancer. The M score of each sample was calculated as the sum of the corresponding log hazard ratio coefficients derived from multivariate logistic regression analysis of methylation status of various genes for benign prostatic hyperplasia and prostate cancer. The optimal sensitivity and specificity of the M score for diagnosis and for staging of prostate cancer was determined by receiver-operator characteristic (ROC) curve analysis. A pairwise comparison was employed to test for significance using the area under the ROC curve analysis. For each clinicopathologic finding, the association with prostate-specific antigen (PSA) failure-free probability was determined using Kaplan-Meier curves and a log-rank test was used to determine significance. The relationship between M score and clinicopathologic findings was analyzed by either the Mann-Whitney U test, Kruskal-Wallis test, or the Spearman rank correlation test. RESULTS: The frequency of positive methylation-specific PCR bands for APC, GSTP1, and MDR1 genes in prostate cancer samples was 64.1%, 54.0%, and 55.3%, respectively. In benign prostatic hyperplasia samples, it was 8.7%, 5.8%, and 11.6%, respectively. There was a significant correlation of M score with high pT category (P < 0.001), high Gleason sum (P < 0.001), high preoperative PSA (P = 0.027), and advanced pathologic features. For all patients, the M score had a sensitivity of 75.9% and a specificity of 84.1% as a diagnostic biomarker using a cutoff value of 1.0. In patients with low or borderline PSA levels (<10.0 ng/mL), the M score was significantly higher in prostate cancers than in benign prostatic hyperplasias (2.635 +/- 0.200 and 0.357 +/- 0.121, respectively). ROC curve analysis revealed that the M score had a sensitivity of 65.4% and a specificity of 94.2% when 1.0 was used as a cutoff value. For all patients, M score can distinguish organ-confined (< or =pT(2)) from locally advanced cancer (> or =pT(3)) with a sensitivity of 72.1% and a specificity of 67.8%. Moreover, considering patients with PSA levels of <10 ng/mL, the M score has a sensitivity of 67.1% and a specificity of 85.7%. The ROC curve analysis showed a significant difference between M score and PSA (P = 0.010). CONCLUSIONS: This is the first report demonstrating that M score is a new method for multigene methylation analysis that can serve as a good diagnostic and staging biomarker for prostate cancer.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2005

Ethnic group-related differences in CpG hypermethylation of the GSTP1 gene promoter among African-American, Caucasian and Asian patients with prostate cancer.

The incidence and mortality of prostate cancer (PC) is approximately 2-fold higher among African-Americans as compared to Caucasians and very low in Asian. We hypothesize that inactivation of GSTP1 genes through CpG methylation plays a role in the pathogenesis of PC, and its ability to serve as a diagnostic marker that differs among ethnic groups. GSTP1 promoter hypermethylation and its correlation with clinico-pathological findings were evaluated in 291 PC (Asian = 170; African-American = 44; Caucasian = 77) and 172 benign prostate hypertrophy samples (BPH) (Asian = 96; African-American = 38; Caucasian = 38) using methylation-specific PCR. In PC cells, 5-aza-dC treatment increased expression of GSTP1 mRNA transcripts. The methylation of all CpG sites was found in 191 of 291 PC (65.6%), but only in 34 of 139 BPH (24.5%). The GSTP1 hypermethylation was significantly higher in PC as compared to BPH in each ethnic group (p < 0.0001). Logistic regression analysis (PC vs. BPH) showed that African-Americans had a higher hazard ratio (HR) (13.361) compared to Caucasians (3.829) and Asian (8.603). Chi-square analysis showed correlation of GSTP1 hypermethylation with pathological findings (pT categories and higher Gleason sum) in Asian PC (p < 0.0001) but not in African-Americans and Caucasian PC. Our results suggest that GSTP1 hypermethylation is a sensitive biomarker in African-Americans as compared to that in Caucasians or Asian, and that it strongly influences tumor progression in Asian PC. Ours is the first study investigating GSTP1 methylation differences in PC among African-American, Caucasian and Asian.

Adult↗
PubMed2004

CpG hypermethylation of MDR1 gene contributes to the pathogenesis and progression of human prostate cancer.

Multidrug resistance 1 (MDR1) gene encodes for P-glycoprotein (P-gp), a Mr 170,000 transmembrane calcium-dependent efflux pump that is inactivated in prostate cancer. We hypothesize that inactivation of the MDR1 gene through CpG methylation contributes to the pathogenesis and progression of prostate cancer. To test this hypothesis, CpG methylation status of the MDR1 promoter and its correlation with clinicopathological findings were evaluated in 177 prostate cancer samples and 69 benign prostate hypertrophy (BPH) samples. Cellular proliferation index and apoptotic index were determined by proliferating cell nuclear antigen (PCNA) and single-strand DNA immunostaining, respectively. After 5-aza-2'-deoxycytidine treatment, increased expression of MDR1 mRNA transcript was found in prostate cancer cell lines (DU145, DuPro, and ND1). MDR1 methylation frequency was significantly higher in prostate cancer samples compared with BPH samples (54.8 versus 11.6%, respectively, P < 0.001). Logistic regression analysis revealed that PC patients are 11.5 times more likely to have MDR1 methylation than BPH patients (95% confidence interval 4.87-27.0) and that MDR1 methylation is independent of the age. Significant correlation of MDR1 methylation was observed with high pT category (P < 0.001), high Gleason sum (P = 0.008), high preoperative prostate-specific antigen (P = 0.01), and advancing pathological features. In addition, PCNA-labeling index were significantly higher in methylation-specific PCR (MSP)-positive than in MSP-negative prostate cancer samples (P = 0.048). In contrast, no significant difference in apoptotic index was found between MSP-positive and -negative prostate cancer samples. These findings suggest that CpG hypermethylation of MDR1 promoter is a frequent event in prostate cancer and is related to disease progression via increased cell proliferation in prostate cancer cells.

Aged↗
PubMed2004

Renal silica calculi in an infant.

We report on a rare case of urinary silica calculi in a 10-month-old boy. The boy showed acute pyelonephritis with left hydronephrosis. Ultrasonography and computed tomography revealed a calculus at the left ureteropelvic junction and three additional calculi in the left renal pelvis. Because his acute pyelonephritis was refractory to conventional chemotherapy, the patient underwent successful left percutaneous nephrostomy followed by percutaneous nephrolithotripsy for the renal calculi. All stones disappeared and his postoperative course was uneventful. On infrared spectrophotometry, the wavelength pattern of the stones exhibited two peaks at 1100 and 1650 cm(-1), consistent with the determination that the calculi consisted of a mixture of silicate (78%) and calcium oxalate (22%). We consider that the etiology of the calculi in this child can be ascribed to the silicate-rich water used to dilute milk. In Japan, 46 adult patients with urinary silicate calculi have been reported in the literature; however, there is no report of the disease in an infant in Japan.

Combined Modality Therapy↗
PubMed2002

Endoscopic removal of intravesical thermometer using a rigid nephroscope and forceps.

Intravesical thermometers are occasionally encountered in urologic practice. In the present paper, we describe the removal of a thermometer from the bladder of a woman who presented with irritable bladder symptoms. The thermometer was removed intact transurethrally using a rigid nephroscope and forceps, even though both ends of the thermometer were embedded in the bladder wall. Our retrieval technique may be of general use in such cases, and it should be attempted before resorting to open surgery.

Adult↗
PubMed2002

An epidemiologic survey of methicillin-resistant Staphylococcus aureus by combined use of mec-HVR genotyping and toxin genotyping in a university hospital in Japan.

OBJECTIVE: To evaluate the usefulness of an assay using two polymerase chain reaction-based genotyping methods in the practical surveillance of methicillin-resistant Staphylococcus aureus (MRSA). METHODS: Nosocomial infection and colonization were surveyed monthly in a university hospital in Japan for 20 months. Genotyping with mec-HVR is based on the size of the mec-associated hypervariable region amplified by polymerase chain reaction. Toxin genotyping uses a multiplex polymerase chain reaction method to amplify eight staphylococcal toxin genes. RESULTS: Eight hundred nine MRSA isolates were classified into 49 genotypes. We observed differing prevalences of genotypes for different hospital wards, and could rapidly demonstrate the similarity of genotype for outbreak isolates. The incidence of genotype D: SEC/TSST1 was significantly higher in isolates causing nosocomial infections (49.5%; 48 of 97) than in nasal isolates (31.4%; 54 of 172) (P = .004), suggesting that this genotype may represent the nosocomial strains. CONCLUSION: The combined use of these two genotyping methods resulted in improved discriminatory ability and should be further investigated.

Bacterial Toxins↗
PubMed1999

Activities of beta-lactams, fluoroquinolones, amikacin and fosfomycin alone and in combination against Pseudomonas aeruginosa isolated from complicated urinary tract infections.

Using the checkerboard titration method as well as the time-kill curve technique, we investigated the activities of beta-lactams, fluoroquinolones, amikacin, and fosfomycin alone and in combination against Pseudomonas aeruginosa isolated from patients with complicated urinary tract infections. In the checkerboard titration studies, none of 21 combinations demonstrated antagonism against 26 strains tested, and the mean fractional inhibitory concentration (FIC) indices for these combinations ranged between 0.4694 and 0.9828. Corresponding to the respective FIC indices, the bactericidal activity determined in combinations of meropenem with ciprofloxacin or amikacin and ceftazidime with ciprofloxacin at sub-minimum inhibitory concentrations (MICs) produced a great reduction in bacterial counts (>/=2 log10 CFU/ml) within 6 h of administration against most of the strains, including strains resistant to one or both drugs, and these synergistic effects were confirmed morphologically by scanning electron microscopy. In time-lag combinations, the first administration of ciprofloxacin or amikacin supplemented by meropenem with 1-h lag diminished bactericidal activity, in comparison with the simultaneous administration of the drugs. These results suggest that simultaneous combinations of beta-lactams with fluoroquinolones or amikacin may be useful alternatives for the treatment of serious infections due to P. aeruginosa.

Journal Article↗