Search PubMed⌕ Search

Biomedical subjects

Masaki Inoue

Publications and source records attributed to Masaki Inoue.

At least 73 records · Page 4Linked to original sources
PubMed2003

Successful treatment of a symptomatic uterine leiomyoma in a perimenopausal woman with a nonsteroidal aromatase inhibitor.

OBJECTIVE: To assess the management of symptomatic leiomyomas using a nonsteroidal aromatase inhibitor in perimenopausal women. DESIGN: Case report. SETTING: Academic clinical practice. PATIENT(S): A 53-year-old woman suffering from recurrent urinary retention secondary to a uterine leiomyoma. INTERVENTION(S): Fadrozole, orally, 2 mg daily for 8 weeks and then 1 mg daily for 4 weeks. MAIN OUTCOME MEASURE(S): Measurements of leiomyoma volume, and levels of serum E(2), LH, and FSH. RESULT(S): Urinary retention resolved after 2 weeks of treatment and did not recur. Leiomyoma volume estimated by ultrasonography revealed a 71% reduction after 8 weeks of treatment. CONCLUSION(S): Fadrozole was useful for the management of a symptomatic leiomyoma without transient deterioration of symptoms. Clinical trials are warranted.

Aromatase Inhibitors↗
PubMed2003

Fetal DNA levels in maternal blood correlated with fetal prognosis in a case of intervillous hematoma.

Several methods for detection of fetal components in maternal blood have been reported. However, few have proven clinically useful for determining the treatment in cases of placental injuries. Here, we report a case of extensive intervillous hematoma diagnosed at 25 weeks of gestation with severe intrauterine growth restriction and oligohydramnios. Marked elevation of fetal DNA levels was observed in maternal blood. Fetal DNA levels decreased after 27 weeks of gestation, concurrent with recovery of fetal growth. We conservatively managed this case until 30 weeks of gestation, when a male infant was delivered. He weighed 508 g and displayed Apgar scores of 7 at 1 minute and 9 at 5 minutes. Histological examination of the placenta revealed intervillous thrombosis without infarction or inflammatory changes. In this case, decreasing fetal DNA levels in maternal plasma correlated with recovery of fetal growth and provided useful information for fetal management as well as insight into the pathogenesis of placental injuries.

Adult↗
PubMed2003

Genetic polymorphisms of CYP2C8 in Japanese population.

CYP2C8 plays important roles in metabolizing therapeutic drugs and endogenous compounds. Although genetic polymorphisms of CYP2C8 were reported, there is little information on CYP2C8 polymorphisms in the Japanese population. In the present study, we screened for previously described polymorphisms in the coding region of this gene using polymerase chain reaction (PCR)-restriction fragment length polymorphism or allele specific-PCR analyses. Eleven polymorphisms of CYP2C8*2 (I269F), CYP2C8*3 (R139K, K399R), CYP2C8*4 (I264M), CYP2C8*5 (frameshift), T130N, E154D, N193K, K249R, L390S, P404A, and H411L have been comprehensively investigated in at least 200 Japanese individuals. A single subject was heterozygous for CYP2C8*5, and the allele frequency was calculated as 0.0025. The other single nucleotide polymorphisms (SNPs) were not found in the Japanese subjects in the present study. Thus, it appears that the frequencies of these alleles in Japanese are extremely low. In addition, concerning the SNPs of T130N, E154D, N193K, K249R, and H411L, it remains clear that these alleles exist as polymorphisms or represent sequence errors or cloning artifacts. Although several SNPs such as CYP2C8*2, CYP2C8*3, CYP2C8*4, and P404A have been reported to reduce the enzymatic activity, pharmacokinetic abnormalities of drugs metabolized by polymorphic CYP2C8 might be rare in Japanese.

Aryl Hydrocarbon Hydroxylases↗
PubMed2002

Is the telomerase assay useful for screening of endometrial lesions?

Telomerase activation is specifically observed in most cancers but not in normal tissues with some exceptions, such as germ cells or certain tissues with regenerative potential, suggesting a diagnostic opportunity for cancers involving measurement of telomerase activity. Cytologic screening for endometrial cancer has not been well established, due to the complexity of diagnostic criterion. In the present study, we investigated the utility of the telomerase assay for screening endometrial lesions. A total of 100 patients with or without endometrial lesions were examined for telomerase activity by the telomeric repeat amplification protocol (TRAP) assay using endometrial scraping samples and the correlation with cytology was investigated. The TRAP assay revealed frequent telomerase activation in normal endometria at reproductive age, particularly in 67% of proliferative-phase endometria, suggesting that the telomerase assay is not suitable for screening women of reproductive age. However, in postmenopausal women, telomerase activity was rarely detected (8%) in normal endometria, while it was observed in >80% of endometrial cancers or hyperplasias. Interestingly, some cases of endometrial cancer and hyperplasia were misdiagnosed by cytology but correctly detected by the TRAP assay. The sensitivity of the TRAP assay to screen endometrial lesions was 87%, equivalent to that of cytology. Combination of cytology and the TRAP assay increased sensitivity to 100%. We thus concluded that measuring telomerase activity in endometrial scrapings is a useful diagnostic tool for the screening of endometrial lesions in postmenopausal women, particularly when used with cytology to increase screening sensitivity.

Adult↗
PubMed2002

Direct activation of telomerase by EGF through Ets-mediated transactivation of TERT via MAP kinase signaling pathway.

Telomerase is a regulated enzyme and its activity is tightly associated with cell proliferation. The mechanisms of this association are unclear, but specific growth factors may regulate telomerase activity. The present study examines the effect of epidermal growth factor (EGF) on telomerase activity and identifies the signal transduction pathway involved in this process. EGF up-regulated telomerase activity in EGF receptor-positive cells after the activation of telomerase reverse transcriptase (TERT) mRNA expression. This activation was rapid, peaked after 6 or 12 h and was not blocked by the concurrent exposure to cycloheximide, suggesting a direct effect of EGF on TERT transcription. Transient expression assays revealed that EGF activates the hTERT promoter and that the proximal core promoter is responsible for this regulation. The activation of hTERT mRNA expression by EGF was specifically blocked by MEK inhibitor, and in vitro kinase assays demonstrated that ERK is activated in response to EGF. Transient expression assays using mutant reporter plasmids revealed that an ETS motif located in the core promoter of hTERT is required for the EGF-induced transactivation of hTERT. Overexpression of wild type Ets in cells enhanced the EGF effect on hTERT transcription, while that of dominant negative Ets significantly repressed EGF action. These findings suggest that EGF activates telomerase through the direct activation of TERT transcription, in which the Ras/MEK/ERK pathway and Ets factor play major roles. Our data support the notion that growth factors directly regulate telomerase via specific signal transduction pathways.

3T3 Cells↗
PubMed2002

Caspase-8 gene therapy using the human telomerase reverse transcriptase promoter for malignant glioma cells.

Telomerase is a distinctive candidate for targeted gene therapy of malignant gliomas, because the vast majority of malignant gliomas express telomerase activity while normal brain tissues do not. Recently, we developed a telomerase-specific expression system of caspase-8 gene using the promoter of the human telomerase reverse transcriptase (hTERT) gene. However, the transcriptional activity of hTERT-181 promoter (a 181-base pair [bp] region upstream of the transcription start site) was relatively lower in malignant glioma cells than in other tumors such as prostate cancer cells. To establish the hTERT/caspase-8 construct as a novel therapy for malignant gliomas, we need to increase the transcriptional activity of the hTERT promoter in malignant glioma cells. In the present study, we demonstrate that the transcriptional activity of hTERT-378 promoter (a 378-bp region) was 2- to 40-fold higher in hTERT-positive malignant glioma cells (A172, GB-1, T98G, U87-MG, U251-MG, and U373-MG) than that of hTERT-181. We further demonstrate that by using the hTERT-378/caspase-8 construct, apoptosis was restricted to malignant glioma cells, and was not seen in astrocytes or fibroblasts lacking hTERT. Moreover, the growth of subcutaneously established U373-MG tumors in mice was significantly inhibited by seven daily intratumoral injections of hTERT-378/caspase-8 construct and its inhibitory effect persisted during 3 additional weeks without additional treatment. These results suggest that the telomerase-specific expression of caspase-8 under hTERT-378 promoter is a novel targeting approach for the treatment of telomerase-positive malignant gliomas.

Animals↗
PubMed2002

Tamoxifen regulates human telomerase reverse transcriptase (hTERT) gene expression differently in breast and endometrial cancer cells.

Tamoxifen is widely applied as an antiestrogenic agent for adjuvant therapy in the treatment of breast cancer, while its estrogen-agonistic activity occasionally causes proliferative disorders or carcinogenesis at other sites, such as the uterus. We reported that estrogen activates telomerase in breast and endometrial cancer cells. The present study examines the effects of tamoxifen on the gene expression of human telomerase reverse transcriptase (hTERT) in breast and endometrial cancer cells. Tamoxifen inhibited the cell growth of MCF-7 cells, as well as hTERT mRNA expression in the presence of estrogen (E2), antagonizing the E2 effects. In contrast, tamoxifen stimulated the growth of Ishikawa cells and activated hTERT mRNA expression in the absence or presence of E2, exhibiting estrogen-agonistic action. Transient expression assays revealed that these actions of tamoxifen are achieved by transcriptional regulation of the hTERT promoter. An estrogen responsive element (ERE) in the hTERT 5' regulatory region was partly responsible for both the E2-antagonistic and -agonistic actions of tamoxifen. Tamoxifen activated the MAP kinase cascade in Ishikawa cells, but not in MCF-7 cells, and the activation of hTERT mRNA expression was effectively blocked by MEK inhibitor, suggesting that the MAP kinase pathway is involved in the tamoxifen-induced activation of hTERT. These findings indicate that tamoxifen regulates hTERT expression in a cell-type specific manner. Tamoxifen-induced activation of hTERT may be one component of estrogen agonistic function of tamoxifen that is involved in endometrial carcinogenesis induced by this agent.

5' Flanking Region↗
PubMed2002

Complex regulatory mechanisms of telomerase activity in normal and cancer cells: how can we apply them for cancer therapy?

Telomerase activation is observed in almost 90% of human cancers but not in normal tissues of somatic origin and thus is a critical step for multistep carcinogenesis. A more thorough understanding of telomerase regulation may provide not only a molecular basis of cancer progression but also as a way to manipulate telomerase activity as a potential therapeutic modality. Recent progress in studies on telomerase regulation has shown that telomerase activation is achieved at various steps, including transcriptional and post-transcriptional levels of the telomerase reverse transcriptase (hTERT) gene. Although a number of potentially important mechanisms of telomerase activation have been proposed, none of the current models can fully explain tumor-specific activation of telomerase, suggesting a need for further extensive analysis. This review includes a summary of recent works on telomerase regulation and a discussion of how we can overcome this situation.

Alternative Splicing↗
PubMed2002

2-5A antisense therapy directed against human telomerase RNA inhibits telomerase activity and induces apoptosis without telomere impairment in cervical cancer cells.

Human telomerase RNA (hTR), an important component of telomerase, is a possible target of telomerase-based cancer gene therapy. The present study was undertaken to assess the efficacy of antisense hTR therapy using newly developed 2-5A (5'-phosphorylated 2'-5'-linked oligoadenylate)-linked oligonucleotides against cervical cancer cells. ME180 and SiHa cells were treated with 2-5A-linked antisense hTR designed to complement the region of hTR between residues 76 and 94. The hTR expression, telomerase activity, cell viability, and apoptosis were then examined. The 2-5A anti-hTR effectively degraded hTR and inhibited telomerase activity. The 2-5A mutant anti-hTR and the anti-hTR without 2-5A were not capable of inhibiting telomerase activity. Inhibition of telomerase by 2-5A anti-hTR rapidly decreased cell viability only in telomerase-positive cells within 3-6 days after the treatment, when telomere length has not yet been shortened. This inhibition was associated with apoptosis, possibly through activation of caspase family members. These findings suggest that 2-5A-linked antisense-hTR therapy has a potent telomerase-inhibitory effect associated with a cytocidal effect from caspase-induced apoptosis, and may therefore be a potential tool in telomerase-based gene therapy against cervical cancers.

Apoptosis↗
PubMed2002

Direct prediction of amniotic fluid volume in the third trimester by 3-dimensional measurements of intrauterine pockets: a tool for routine clinical use.

OBJECTIVE: To develop an ultrasonographic technique for direct prediction of amniotic fluid volume. STUDY DESIGN: While women with near-term pregnancies were in the supine position, the intrauterine space was divided into 2 hemispheres and each hemisphere was further subdivided into 3 segments. The maximum distances along the 3 axes of amniotic fluid pocket in each segment were measured, and the volume was calculated as a half-ellipsoid or a crescent-cylinder. A sum of these calculations (prediction of amniotic fluid volume [pAFV]) was made and correlated with amniotic fluid volume measured at delivery (mAFV). RESULTS: In 714 deliveries, a high correlation coefficient of 0.896 between mAFV (mean +/- SD, 296.5 +/- 199.2 mL; range, 20 to 1480 mL) and pAFV (mean +/- SD, 300.2 +/- 180.8 mL; range, 27 to 1262 mL) was obtained. The regression equation was mAFV = 0.968pAFV + 8.68. CONCLUSION: The regression equation suggested that pAFV could be a direct predictor of intrauterine amniotic fluid volume in the third trimester.

Amniotic Fluid↗
PubMed2002

Overexpression of aromatase P450 in leiomyoma tissue is driven primarily through promoter I.4 of the aromatase P450 gene (CYP19).

The CYP19 gene encoding aromatase P450 (estrogen synthetase) is expressed in several extragonadal sites and regulated in a tissue-specific fashion, which is achieved by alternative use of the seven different promoters (and corresponding exons 1) of the CYP19 gene. Previously, we demonstrated that aromatase P450 is overexpressed in leiomyoma tissue and that in situ estrogen synthesized in leiomyoma tissues possibly plays a role in leiomyoma growth. To elucidate the mechanism of overexpression of aromatase P450, we determined the promoter use of aromatase P450 in leiomyomas. 5'-Rapid amplification of cDNA ends analysis revealed that of six leiomyoma nodules tested, four nodules contained I.4-specific transcript of aromatase P450 alone, one nodule contained PII-specific transcript alone, and the remaining nodule contained both I.4- and PII-specific transcripts simultaneously. The levels of aromatase transcripts were then quantified by competitive RT-PCR assay. Among 21 leiomyomas, I.4-specific transcript and PII-specific transcript were predominant in 18 and 2 leiomyomas, respectively, whereas the remaining leiomyoma was negative for aromatase P450 expression. We next compared the aromatase activity of leiomyoma cells stimulated by promoter-specific regulatory factors. A combination of IL-1beta and dexamethasone, known as a potent inducer of promoter I.4-driven transcription, effectively increased aromatase activity. A combination of (Bt)(2)cAMP, 3-isobutyl-1-myethylxanthine, and PGE(2), known as inducers of promoter II-driven transcription, also increased aromatase activity, but the increases found were smaller than that induced by dexamethasone and IL-1beta. The transcriptional ability of the promoter I.4 sequence was confirmed by transient transfection assay using primary cells released from leiomyomas and established cells from normal myometrium (KW cells). Luciferase vectors containing promoter I.4 sequence (-340/+14 or longer) showed a significant increase in luciferase activity in response to dexamethasone. Deletion or mutation of a putative glucocorticoid-responsive element in the promoter I.4 sequence eliminated promoter activity. These results indicate that promoter I.4 is the major promoter responsible for overexpression of aromatase P450 in leiomyomas and that a glucocorticoid-responsive element within it plays a substantial role in the expression of aromatase P450.

Adult↗
PubMed2002

Spatially heterogeneous expression of aromatase P450 through promoter II is closely correlated with the level of steroidogenic factor-1 transcript in endometrioma tissues.

Endometriosis is an estrogen-dependent disease of women of reproductive age. Recent studies demonstrate that endometriosis per se express high levels of estrogen synthetase (aromatase P450). The resulting estrogen synthesized in situ may play a role in the development and exacerbation of the disease. For ovarian endometrioma, previous studies have been conducted ex vivo using cells obtained from endometrioma and have demonstrated that steroidogenic factor-1 is involved in the expression of aromatase. The aim of the present study was to provide in vivo evidence that steroidogenic factor-1 plays an important role in the regulation and overexpression of aromatase P450 in situ. First, promoter use of aromatase P450 in endometrioma tissue was determined using quantitative methods. Ovarian endometrioma tissue was chopped into small pieces, and two exon 1-specific transcripts of aromatase P450 (PII-specific and I.4-specific transcripts) were quantified using competitive RT-PCR. PII-specific transcript was more abundant than the I.4-specific transcript in 13 of the 15 endometriomas and less abundant in the remaining two. Spatial distribution of aromatase P450 transcripts in these endometrioma tissues revealed heterogeneous expression in the cyst wall, demonstrating wide variability even in the same endometrioma. Two possible regulators of aromatase expression (steroidogenic factor-1 and IL-1 beta) were then measured in all endometrioma samples and the correlation between aromatase P450 transcripts and these possible regulators in the endometrioma samples were tested using Spearman's rank order correlation test. Levels of steroidogenic factor-1 transcript were found to correlate closely with levels of PII-specific transcript in eight of nine endometriomas examined. On the other hand, the level of IL-1 beta weakly correlated with I.4-specific transcripts in three of the nine endometriomas. We next histologically examined samples of four endometriomas in which complete sets of tissue samples corresponded to the RNA samples. We could not identify any specific pathology to explain the heterogeneous expression of PII-specific transcripts of aromatase P450, although the number of CD-68 positive macrophages in the tissue sections weakly correlated with the level of I.4-specific transcript in two of four endometriomas. These results provide strong evidence that promoter II is the predominant promoter of aromatase P450 in endometrioma tissues in vivo and that steroidogenic factor-1 in situ is a major determinant of aromatase P450 overexpression in endometrioma tissues in vivo.

Adult↗
PubMed2002

How to inhibit telomerase activity for cancer therapy.

Telomerase is a target for anticancer research because telomerase activity is closely correlated with malignancy. Inhibition of telomerase activity should increase telomere shortening, which destabilizes chromosomes, thus leading to cellular senescence and death. Extensive investigations have addressed the molecular mechanisms of telomerase activation in cancers. Based on results from these studies, various attempts have been made to inhibit telomerase activity using molecular techniques in cancer cells. Antisense oligonucleotides directed to human telomerase RNA, the dominant negative form of human telomerase reverse transcriptase (hTERT), hammerhead ribozymes that cut hTR and agents that interact with quadruplex DNA represent potential telomerase inhibitors. This review includes a summary of recent attempts to inhibit telomerase activity in cancer cells and a discussion of how these tools can be applied to cancer therapy, especially in combination with established anti-cancer agents.

Animals↗
PubMedDate not supplied

Circuit training for elderly patients with chronic obstructive pulmonary disease: a preliminary study.

To examine the efficacy of the circuit training in elderly patients with chronic obstructive pulmonary disease (COPD), we evaluated muscle forces of the upper and lower extremities and respiratory muscles, exercise tolerance and quality of life (QOL) before and after the circuit training in 10 male patients with mild to severe COPD. The circuit training improved muscle forces of the upper and lower extremities and abdominal muscles (P < 0.05), and 6 min walking distance (P < 0.05). Emotional function and mastery in the Chronic Respiratory Disease Questionnaire scores (P < 0.05) were also improved after the circuit training. The circuit training designed in the present study was effective to improve the QOL in elderly COPD patients.

Aged↗
PubMedDate not supplied

Efficacy of the herbal medicine Unkei-to as an adjunctive treatment to hormone replacement therapy for postmenopausal women with depressive symptoms.

OBJECTIVE: Although hormone replacement therapy (HRT) improves menopausal depressive symptoms, women unresponsive to HRT need an antidepressant drug as an effective adjunctive therapy. The aim of this study was to assess whether the herbal medicine Unkei-to has an impact on HRT-resistant menopausal depressive symptoms as an effective adjunctive therapy combined with HRT. METHODS: Twenty-four HRT-resistant menopausal depressive women were randomly assigned to group 1 (n = 12) or group 2 (n = 12). Subjects in group 1 were accessioned into 6 months of open treatment with Unkei-to as an adjunctive therapy and changed to Toki-shakuyaku-san for 6 months following a 1-month washout period. Group 2 started with Toki-shakuyaku-san for 6 months and then changed to Unkei-to for 6 months following a 1-month washout period. RESULTS: Three months' treatment with Unkei-to as an adjunctive therapy significantly improved Zung's Self-Rating Depression Scale (ZSDS) scores, State-Anxiety (STAI-1) scores, and Trait-Anxiety (STAI-2) scores noted before treatment, and this effect continued at 6 months. Treatment with Unkei-to was also significantly effective in reduction of ZSDS scores, STAI-1 scores, and STAI-2 scores at 3 months compared with Toki-shakuyaku-san treatment, and this effect continued at 6 months. CONCLUSIONS: Unkei-to is another option as an adjunctive herbal therapy in HRT-resistant menopausal depressive women.

Aged↗
PubMedDate not supplied

Tumor-associated macrophages: foe or accomplice of tumors?

Macrophages are predominantly involved in the immune and inflammatory processes of solid tumors. Macrophages infiltrated into a tumor have an ambivalent relationship with the tumor, because they are innately very flexible and adaptable depending on the microenvironment of the tissue and the tissue-derived factors. The relationship between tumor-associated macrophages (TAMs) and a tumor is extremely complicated and has not yet been clearly elucidated. Now, the reintegration of biological knowledge including immunology, pathology and oncology is indispensable for the clinical application of TAMs to cancer therapy. In this review, we focus on the range of pro- and anti-tumor functions performed by TAMs and outline a new class of cancer therapies that aims at controlling the complex functions of TAMs.

Animals↗
PubMedDate not supplied

The degree of macrophage infiltration into the cancer cell nest is a significant predictor of survival in gastric cancer patients.

BACKGROUND: Tumor-associated macrophages (TAMs) have varying functions depending on the microenvironment of tumor tissue. We studied the biological role of TAMs in gastric cancer on the basis of their spatial distribution in the cancer tissue. MATERIALS AND METHODS: Tissue specimens from 84 advanced gastric carcinoma (pT2; 41 cases, pT3; 43 cases) patients who had undergone a curative resection were stained for TAM (CD68+ cells), incidence of tumor cell apoptosis (TUNEL) and host immune status (CD8+ T cells). CD68+ and CD8+ T cells infiltrated into the cancer cell nests or in close contact with cancer cells were considered as nest TAMs and nest CD8, respectively. RESULTS: Nest TAMs had a very strong direct correlation with frequency of tumor cell apoptosis (p < 0.0001) and degree of nest CD8 (p = 0.0004). The 5-year disease-free survival rate in the high-nest TAM category (87%) was significantly higher than in the low-nest TAM group (44%) (p = 0.0002). Among the several prognostic factors, nest TAM, nest CD8 and pT stage became independent predictors of patient survival (p = 0.016, p = 0.001 and p = 0.029, respectively) in Cox's multivariate analysis. CONCLUSION: These results suggested that the aggregation of TAMs within tumor nest had a beneficial effect on host in terms of augmented cytotoxicity and antigen presentation.

Adenocarcinoma↗