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Biomedical subjects

Makoto Suzuki

Publications and source records attributed to Makoto Suzuki.

At least 19 recordsLinked to original sources
PubMed2026

Endobronchial Ultrasound-Guided Biopsy-Derived Lung Cancer Models: A Platform for Precision Therapy.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration is used for clinical diagnosis and staging in patients with lung cancer. Nevertheless, establishing patient-derived preclinical models using needle biopsy samples remains challenging. This study describes the establishment and utility of patient-derived organoid (PDO) from endobronchial ultrasound-guided (EBUS) specimens and EBUS patient-derived xenograft (PDX). METHODS: A total of 175 EBUS specimens were used to establish PDO and PDX. "Stable establishment" organoids with passage numbers of 10 or greater were used for genomic, transcriptome, and pathologic assessment. Drug sensitivity of EBUS organoids and PDX tumors were compared with those of the matched patient. Drug screening was performed using stably established organoid models. RESULTS: We successfully established a total of 20 EBUS organoids: six EBUS-PDOs and 14 EBUS-xenograft derived organoids. These stable cancer organoid models were validated for cancer cell enrichment and pathologic assessment. Pathologic findings, exome, and transcriptome analysis found a high correlation between EBUS organoids and parental samples. EBUS organoids and PDX indicated consistent drug response patterns with their corresponding patients. A drug screening conducted on an EBUS organoid led to the discovery of potent activity of trametinib to a rare MAP2K1 K57N mutation. CONCLUSIONS: EBUS-PDO and -xenograft‒derived organoids are good options to generate stable organoids in patients with advanced stage lung cancer. The models were consistent with the genetic and pathologic features of patient tumors, and the patient's responses to treatment, supporting their utility for novel therapeutic research.

Humans↗
PubMed2006

Methylation and gene silencing of the Ras-related GTPase gene in lung and breast cancers.

BACKGROUND: RRAD, a small Ras-related GTPase, is highly expressed in human skeletal muscle, lung, and heart. Although loss of expression of RRAD in breast cancer cells has been reported and it may act as an oncogene, the mechanism of silencing is unknown. METHODS: We examined (1) mRNA expression of RRAD in lung and breast cancer cell lines using RT-PCR and (2) methylation status of lung and breast cancers. RESULTS: Loss of RRAD expression was found in 14 of 20 (70%) NSCLC cell lines, 11 of 11 (100%) SCLC cell lines, and 8 of 10 (80%) breast cancer cell lines; expression was not affected in normal bronchial and mammary epithelial cells. Treatment of 23 expression-negative cell lines with a demethylating agent restored expression in all cases. We developed a methylation-specific assay from the analysis of bisulfite sequencing of the 5' region of RRAD in expression-negative and positive cell lines, which resulted in good concordance between methylation and expression. Primary lung and breast cancers showed hypermethylation in 89 of 214 (42%) and 39 of 63 (62%) cases, respectively. RRAD hypermethylation correlated with smoking history and poorer prognosis in lung adenocarcinomas. CONCLUSIONS: We conclude that epigenetic silencing of RRAD is a frequent event in lung and breast cancers, and analysis of it may provide novel opportunities for prognosis and therapy of these cancers.

Adenocarcinoma↗
PubMed2006

TRPV4 as a flow sensor in flow-dependent K+ secretion from the cortical collecting duct.

The transient receptor vanilloid-4 (TRPV4) is a mechanosensitive, swell-activated cation channel that is abundant in the renal distal tubules. Immunolocalization studies, however, present conflicting data as to whether TRPV4 is expressed along the apical and/or basolateral membranes. To disclose the role of TRPV4 in flow-dependent K(+) secretion in distal tubules in vivo, urinary K(+) excretion and net transports of K(+) and Na(+) in the cortical collecting duct (CCD) were measured with an in vitro microperfusion technique in TRPV4(+/+) and TRPV4(-/-) mice. Both net K(+) secretion and Na(+) reabsorption were flow dependently increased in the CCDs isolated from TRPV4(+/+)mice, which were significantly enhanced by a luminal application of 50 microM 4alpha-phorbol-12,13-didecanoate (4alphaPDD), an agonist of TRPV4. No flow dependence of net K(+) and Na(+) transports or effects of 4alphaPDD on CCDs were observed in TRPV4(-/-) mice. A basolateral application of 4alphaPDD had little effect on these ion transports in the TRPV4(+/+) CCDs, while the luminal application did. Urinary K(+) excretion was significantly smaller in TRPV4(-/-) than in TRPV4(+/+) mice when urine production was stimulated by a venous application of furosemide. These observations suggested an essential role of the TRPV4 channels in the luminal or basolateral membrane as flow sensors in the mechanism underlying the flow-dependent K(+) secretion in mouse CCDs.

Amiloride↗
PubMed2006

Exclusive mutation in epidermal growth factor receptor gene, HER-2, and KRAS, and synchronous methylation of nonsmall cell lung cancer.

BACKGROUND: Both genetic and epigenetic changes in nonsmall cell lung cancer (NSCLC) are known to be a common event. METHODS: Mutations in the epidermal growth factor receptor gene (EGFR), HER-2, and KRAS and the methylation profile of 9 genes for NSCLC were analyzed and correlated with clinical and histologic data. RESULTS: Thirty-nine EGFR, 4 HER-2, and 6 KRAS mutations were found in 150 NSCLC cases, with the methylation percentages of the genes ranging from 13% to 54%. Most mutations were present in adenocarcinomas, but mutations of the 3 genes were never found to be present in individual tumors. The frequency of methylation for all the genes was correlated with the Methylation Index, a reflection of the overall methylation pattern (all genes, P< or = .01), supporting the presence of the CpG island methylator phenotype (CIMP) in NSCLC. On the basis of the methylation profile, CRBP1 and CDH13 methylation were good indicators of CIMP in NSCLC, and were correlated with a poorer prognosis in adenocarcinomas. Mutations in EGFR, HER-2, and KRAS were found to be present exclusively, whereas methylation tended to be present synchronously. A comparison of mutation and methylation demonstrated that the EGFR mutation had an inverse correlation with methylation of SPARC (secreted protein acidic and rich in cysteine), an extracellular Ca2+-binding matricellular glycoprotein associated with the regulation of cell adhesion and growth, and the p16INK4A gene. CONCLUSIONS: The findings of the current study suggest that adenocarcinoma cases with CIMP have a poorer prognosis than adenocarcinoma cases without CIMP, and the EGFR mutation was shown to have an inverse correlation with methylation of SPARC and the p16INK4A gene in NSCLC.

Adult↗
PubMed2006

Limb regeneration in Xenopus laevis froglet.

Limb regeneration in amphibians is a representative process of epimorphosis. This type of organ regeneration, in which a mass of undifferentiated cells referred to as the "blastema" proliferate to restore the lost part of the amputated organ, is distinct from morphallaxis as observed, for instance, in Hydra, in which rearrangement of pre-existing cells and tissues mainly contribute to regeneration. In contrast to complete limb regeneration in urodele amphibians, limb regeneration in Xenopus, an anuran amphibian, is restricted. In this review of some aspects regarding adult limb regeneration in Xenopus laevis, we suggest that limb regeneration in adult Xenopus, which is pattern/tissue deficient, also represents epimorphosis.

Animals↗
PubMed2006

Application of a methylation gene panel by quantitative PCR for lung cancers.

Detection of lung cancer at early stages could potentially increase survival rates. One promising approach is the application of suitable lung cancer-specific biomarkers to specimens obtained by non-invasive methods. Thus far, clinically useful biomarkers that have high sensitivity have proven elusive. Certain genes, which are involved in cellular pathways such as signal transduction, apoptosis, cell to cell communication, cell cycles and cytokine signaling are down-regulated in cancers and may be considered as potential tumor suppressor genes. Aberrant promoter hypermethylation is a major mechanism for silencing tumor suppressor genes in many kinds of human cancers. Using quantitative real time PCR, we tested 11 genes (3-OST-2, RASSF1A, DcR1, DcR2, P16, DAPK, APC, ECAD, HCAD, SOCS1, SOCS3) for levels of methylation within their promoter sequences in non-small cell lung cancers (NSCLC), adjacent non-malignant lung tissues, in peripheral blood mononuclear cells (PBMC) from cancer free patients, in sputum of cancer patients and controls. Of all the 11 genes tested 3-OST-2 showed the highest levels of promoter methylation in tumors combined with lowest levels of promoter methylation in control tissues. 3-OST-2 followed by, RASSF1A showed increased levels of methylation with advanced tumor stage (P<0.05). Thus, quantitative analysis of 3-OST-2 and RASSF1A methylation appears to be a promising biomarker assay for NSCLC and should be further explored in a clinical study. Our preliminary data on the analysis of sputum DNA specimens from cancer patients further support these observations.

Adenocarcinoma↗
PubMed2006

Sun exposure related methylation in malignant and non-malignant skin lesions.

We investigated the aberrant promoter methylation status of 12 genes in skin lesions, both malignant (basal cell carcinomas (BCCs), n=68 and squamous cell carcinomas (SCCs), n=35) and non-malignant (tags, n=58) skin lesions and compared the results of lesions from sun exposed (SE) and sun protected (SP) regions. Methylation was studied using a methylation specific PCR (MSP) and methylation of CDH1 was also measured using a semi-quantitative fluorescence based real-time MSP method. The methylation index (MI) was calculated as the methylated fraction of the genes examined. In this report, we found high frequencies of methylation of several known or suspected tumor suppressor genes in tags and skin cancers. Among the 12 genes, for the cadherin genes CDH1 and CDH3 and for two of the laminin 5 encoding genes LAMA3 and LAMC2 methylation frequencies greater than 30% were noted in one or more specimen types. We investigated whether methylation was tumor related. Surprisingly, the differences in the methylation profile of genes among the three specimen types were modest, and the MI, indicators of overall methylation frequencies, was nearly identical. However, significant differences were noted in the frequencies of methylation among the three specimen types for the genes RASSF1A (P=0.002), CDH1 (P=0.007) and one or more of three CAD genes (P=0.02). Methylation was highly significantly related to sun exposure, and sun protected specimens had little or no methylation. As methylation of CDH1 was completely SE specific we analyzed all the skin samples using a semi-quantitative real-time PCR assay for the CDH1 gene. The concordance between standard MSP and real-time MSP for all the samples (n=161) was 75% (P<0.0001). While weak signals were detected in the SP samples by real time PCR, the differences between SE and SP specimens were 148 fold for tags and 390 fold for BCCs. These differences were highly significant (P<0.0001). These findings suggest that methylation commences in UV exposed skin at a relatively early age and occurs in skin prior to the onset of recognizable preneoplastic changes.

Aged↗
PubMed2006

Aberrant promoter methylation of multiple genes during multistep pathogenesis of colorectal cancers.

Aberrant methylation of 5'gene promoter regions associated with gene silencing is an epigenetic phenomenon responsible for silencing of tumor suppressor genes in many cancer types. The aims of our study were to study the role of methylation of a large panel of genes during multistage pathogenesis and to correlate our findings with patient age and other clinico-pathological features. We investigated the aberrant promoter methylation profile of 19 genes in 92 colorectal cancers (CRCs) and corresponding nonmalignant epithelia (NME) (n = 57), and selected 15 genes for studying 26 colorectal adenomas (CAs). On the Basis of our results, the genes could be divided into 3 groups. Group 1 consisted of 13 genes whose methylation was tumor-specific. For 8 of these genes, the methylation frequencies in CAs were similar to those of CRCs, but significantly different from the frequencies in NME. Group 2, consisting of 2 genes demonstrating little or no methylation, were present in any sample type. In Group 3, consisting of 4 genes, relatively frequent methylation was present in both CRCs and NME, and the differences between these specimen types were not significant. Methylation of Group 1 genes were tightly correlated with each other, and these genes demonstrated increased methylation frequencies in CRCs with increasing age. Methylation was not correlated with other clinico-pathological features. In general, methylation frequencies of CAs were intermediate between CRCs and NME. Our study constitutes the most comprehensive methylation profile of CRCs, demonstrates that methylation commences early during CRC pathogenesis and is an age-related phenomenon.

Aged↗
PubMed2006

Functional expression of transient receptor potential vanilloid 4 in the mouse cochlea.

Transient receptor potential vanilloid 4, the Ca2+-permeable cation channel has been proposed as an osmosensitive and a mechanosensitive channel. We investigated functional expression of transient receptor potential vanilloid 4 in inner hair cells, outer hair cells, and spiral ganglion neurons of the mouse cochlea. Transient receptor potential vanilloid 4 mRNA and protein were expressed in inner hair cells, outer hair cells, and spiral ganglion neurons on the basis of the findings of reverse transcriptase-polymerase chain reaction, single-cell reverse transcriptase-polymerase chain reaction, and immunohistochemistry, whereas they were negative in transient receptor potential vanilloid 4-/- mice cochleae. Hypotonic stimulation and 4-alpha-phorbol 12,13-didecanoate, a transient receptor potential vanilloid 4 synthetic activator, increased the intracellular Ca2+ concentrations in wild-type outer hair cells, whereas in transient receptor potential vanilloid 4-/- mice, outer hair cells failed to exhibit a Ca2+ response to both stimulations. In conclusion, transient receptor potential vanilloid 4 may function as an osmosensory and a mechanosensory receptor in the cochlea.

Animals↗
PubMed2006

Methylation of apoptosis related genes in the pathogenesis and prognosis of prostate cancer.

We investigated aberrant methylation in 101 prostate cancers(PCa) and 32 histologically normal prostate tissues. We focused on genes largely in the apoptotic pathway. Methylation frequencies of the genes were Reprimo, 54%; TMS1, 47%; DcR1, 45%; RRAD, 37%; DcR2, 37%; CRBP1, 34%; HPP1, 32%; RIZ1, 31%; DRM/Gremlin, 21%; SOCS1, 20%; DR4, 5%; DR5, 1%. Methylation of Reprimo and TMS1 correlate with preoperative serum prostate-specific antigen. Methylation of TMS1, DcR1, DcR2, and CRBP1 correlate with Gleason score. Methylation of TMS1 and unmethylation of both DcR1 and DcR2 correlate with poorer disease free survival by univariate and multivariate analyses. Our data suggest that methylation of multiple genes may be involved in pathogenesis and correlate with prognosis of PCa.

Adult↗
PubMed2006

Mutational and epigenetic evidence for independent pathways for lung adenocarcinomas arising in smokers and never smokers.

Genetic and epigenetic alterations are considered to play important roles in lung cancer. Recent studies showed that EGFR and K-RAS mutations exhibited a mutually exclusive pattern in adenocarcinoma of the lung, suggesting the presence of two independent oncogenic pathways. However, it is unknown how epigenetic alterations were involved in lung carcinogenesis mediated by EGFR or K-RAS mutation. In this study, we examined the relationship between genetic and epigenetic alterations in 164 cases of lung adenocarcinoma. Somatic mutations were determined by direct sequence of EGFR exons 18 to 21 and K-RAS codons 12 and 13. Methylation status of p16(INK4a), RASSF1A, APC, RARbeta, and CDH13, frequently methylated in lung cancer, was determined by methylation-specific PCR and the degree of methylation was defined as the methylation index. Multivariate analysis adjusted for age, sex, and smoking dose showed that the probability of having EGFR mutation was significantly lower among those with p16(INK4a) and CDH13 methylation than in those without [p16(INK4a): odds ratio (OR), 0.07; 95% confidence interval (95% CI), 0.02-0.33; CDH13: OR, 0.34; 95% CI, 0.15-0.77] and the methylation index was significantly lower in EGFR mutant cases than in wild type (OR, 0.70; 95% CI, 0.52-0.95). By contrast, K-RAS mutation was significantly higher in p16(INK4a) methylated cases than in unmethylated cases (OR, 4.93; 95% CI, 1.54-15.7) and the methylation index was higher in K-RAS mutant cases than in wild type with marginal significance (OR, 1.46; 95% CI, 0.95-2.25). Our results indicate the differences in the evolvement of epigenetic alterations between the EGFR- and K-RAS-mediated tumorigenesis and suggest the specific interaction of genetic and epigenetic changes in tumorigenesis of lung cancer.

Adenocarcinoma↗
PubMed2006

Pharmacological characterization and feeding-suppressive property of FMS586 [3-(5,6,7,8-tetrahydro-9-isopropyl-carbazol-3-yl)-1-methyl-1-(2-pyridin-4-yl-ethyl)-urea hydrochloride], a novel, selective, and orally active antagonist for neuropeptide Y Y5 receptor.

We evaluated the pharmacological profiles of FMS586 [3-(5,6,7,8-tetrahydro-9-isopropyl-carbazol-3-yl)-1-methyl-1-(2-pyridin-4-yl-ethyl)-urea hydrochloride], a novel tetrahydrocarbazole derivative as a neuropeptide Y (NPY) Y5 receptor antagonist. This compound showed a highly selective in vitro affinity for Y5 (IC(50) = 4.3 +/- 0.4 nM) relative to other NPY receptor subtypes like Y1 or Y2. Its binding to Y5 was found to be fully antagonistic from cyclic AMP accumulation assays in human embryonic kidney 293 cells. Pharmacokinetic analysis revealed sufficient oral availability and brain permeability of this compound accompanied with clear dose relation. We attempted to assess the selectivity of FMS586 and, thereby, to infer the physiological role of Y5 in the following feeding experiments in normal rats. An intracerebroventricular injection of NPY and Y5-selective agonist peptide induced acute and robust feeding responses in satiated rats, and prior administration of FMS586 at the doses from 25 to 100 mg/kg clearly inhibited these responses by approximately 55 and 90%, respectively. This compound also showed dose-dependent but transient suppression in natural feeding models of both overnight fasting-induced hyperphagia and spontaneous daily intake. FMS586 did not modulate food intake induced by the topical injection of norepinephrine, galanin, or gamma-aminobutyric acid receptor agonist muscimol to the paraventricular nucleus. In addition, we confirmed the Y5-specific activity profile of FMS586 by immunohistochemical analysis. Taken together, we propose not only that our compound potentially expresses specific blockade of central Y5 signals but also that Y5 receptor would certainly contribute to physiological regulation of food intake in normal rats, as suggested from its origin.

Administration, Oral↗
PubMed2006

Spontaneous regression of bone metastasis from renal cell carcinoma; a case report.

BACKGROUND: Spontaneous regression of metastatic renal cell carcinoma is rarely observed. CASE PRESENTATION: Metastatic renal cell carcinoma was identified in a 70-year-old male using computed tomography-guided percutaneous needle biopsy. Two months after the diagnosis, a partial resection of the sternal bone was performed. Pathological examination revealed granulated tissue with bleeding and necrosis but no carcinogenic cells. CONCLUSION: We report a pathologically identified case in which a sternal bone metastasis that was noticed two years after radical nephrectomy regressed completely and spontaneously.

Aged↗
PubMed2006

Analysis of scleraxis and dermo-1 genes in a regenerating limb of Xenopus laevis.

Xenopus laevis larvae can regenerate an exact replica of the missing part of a limb after amputation at an early limb bud stage. However, this regenerative capacity gradually decreases during metamorphosis, and a froglet is only able to regenerate hypomorphic cartilage, resulting in a spike-like structure (spike). It has been reported that the spike has tissue deformities, e.g., a muscleless structure. However, our previous study demonstrated that the muscleless feature of the spike can be improved. The existence of other kinds of tissue, such as tendon, has not been clarified. In this study, we focused on the tendon and dermis, and we isolated the scleraxis and dermo-1 genes, which are known to be marker genes for the tendon and dermis, respectively. The expressions of these genes were investigated in both the developmental and regenerating processes of a Xenopus limb. Although muscle was needed to maintain scleraxis expression, scleraxis transcription was detectable in the muscleless spike. Additionally, although grafting of matured skin, including dermal tissue, inhibited limb regeneration, the expression of dermo-1, a dermal marker gene, was detected from the early stage of the froglet blastema. These results indicate that tendon precursor cells and dermal cells exist in the regenerating froglet blastema. Our results support the idea that spike formation in postmetamorphic Xenopus limbs is epimorphic regeneration.

Amino Acid Sequence↗
PubMed2006

An example that presented giant aneurysm of the angina pectoris after percutaneous coronary intervention.

We present the case of a 70-year-old woman who was admitted to our hospital with heart failure due to a giant left ventricular aneurysm involving the apex and severe mitral regurgitation. Three months before the hospitalization, percutaneous coronary intervention was performed for severe stenosis of the left main trunk. During the procedure, there were no abnormalities of distal coronary flow due to problems like embolization, and repeat coronary angiography, performed after stabilization of heart failure, showed no new significant stenosis. We diagnosed her condition as a subepicardial aneurysm by pathological examination of the resected specimen.

Aged↗
PubMed2006

Caloric restriction and human longevity: what can we learn from the Okinawans?

Caloric (or dietary) restriction (CR) extends lifespan and lowers risk for age associated diseases in a phylogenetically diverse group of species. Whether prolonged CR increases average or maximum lifespan or promotes a more youthful physiology in humans at advanced ages is not yet known. However, available epidemiological evidence indicates that CR may already have contributed to an extension of average and maximum life span in one human population and appears to have lowered risk for age associated chronic diseases in other human populations. We review the human studies in the context of a special human population, older Okinawans, who appear to have undergone a mild form of prolonged CR for about half their adult lives.

Aging↗