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H Kataoka

Publications and source records attributed to H Kataoka.

At least 37 records · Page 2Linked to original sources
PubMed2001

Transforming growth factor-beta1 enhances expression of brain-derived neurotrophic factor and its receptor, TrkB, in neurons cultured from rat cerebral cortex.

The effects of transforming growth factor (TGF)-beta1 on expression of brain-derived neurotrophic factor (BDNF) and its high-affinity receptor, TrkB, in neurons cultured from the cerebral cortex of 18-day-old embryonic rats were examined. BDNF mRNA was significantly increased from 24-48 hr after the TGF-beta1 treatment over 20 ng/ml. Accumulation of BDNF protein in the culture medium was also potentiated by TGF-beta1, although the intracellular content of BDNF was nearly unchanged. The enhancement of BDNF mRNA expression was suppressed by the co-presence of decorin, a small TGF-beta-binding proteoglycan that inhibits the biological activities of TGF-betas. mRNA expression of full-length TrkB, the bioactive high-affinity receptor for BDNF, was also upregulated after treatment with TGF-beta1. These observations suggest that: 1) TGF-beta1 potentiates BDNF/TrkB autocrine or local paracrine system; and 2) the neurotrophic activity of TGF-beta1 is partly responsible for the BDNF induced by TGF-beta1 itself. To test this latter possibility, we examined the neuronal survival activity of TGF-beta1 with or without K252a, a selective inhibitor of Trk family tyrosine kinases. TGF-beta1 significantly enhanced neuronal survival, but the co-presence of K252a completely suppressed the activity, demonstrating the involvement of Trk receptor signaling in TGF-beta1-mediated neuronal survival in cultured rat cortical neurons. These results seem to be in line with recent findings by other investigators that some neurotrophic factors including BDNF require TGF-betas as a cofactor to exert their neurotrophic activities.

Animals↗
PubMed2001

Identification of hepatocyte growth factor activator inhibitor type 2 (HAI-2)-related small peptide (H2RSP): its nuclear localization and generation of chimeric mRNA transcribed from both HAI-2 and H2RSP genes.

A novel small gene, designated hepatocyte growth factor activator inhibitor type 2 (HAI-2)-related small peptide (H2RSP) was cloned and characterized in the process of the search for splicing variant forms of HAI-2 by 3'-rapid amplification of cDNA ends (RACE). The gene consisted of 4 exons spanning approximately 1 kb and was located in 11 kb downstream of HAI-2 gene (19q.13.11). The novel transcript identified by 3'-RACE was thought to be chimerically transcribed from both HAI-2 (exons 1-7) and H2RSP (exons 2-4) genes. Wild-type H2RSP mRNA (0.5 kb) was detected abundantly in various tissues including the gastrointestinal tract, whereas chimeric mRNA (1.5 kb) was found mainly in the kidney, prostate, and placenta by Northern blot analysis. The predicted amino acid sequence of H2RSP contained two unique domains, namely the serine-rich region (exon 3) and the lysine-rich region (exon 4). Transfection of deleted series of H2RSP cDNAs fused to enhanced green fluorescent protein (EGFP) into HeLa cells revealed that H2RSP has nuclear localization signal in the lysine-rich region. Immunohistochemical study using anti-H2RSP polyclonal antibody indeed revealed the nuclear localization of this peptide in vivo. These results suggest that H2RSP and H2RSP/HAI-2 chimeric peptides might function as a transcriptional regulatory peptide at the nucleus.

Amino Acid Sequence↗
PubMed2001

Endoscopic thyroid resection using cutaneous elevation in lieu of insufflation.

BACKGROUND: Laparoscopic surgery to resect cervical masses has gained increasing acceptance during the past decade. This report describes the authors' technique and experience using total video endoscopic surgery to resect thyroid masses. METHODS: The video camera is introduced through a 12-mm trocar inserted via a 10-mm infraclavicular incision in the sternal line. This incision will be hidden by the patient's undergarments postoperatively. An incision for a 12-mm trocar is made in each axilla, with additional incisions in the anterior chest made as necessary for the endoscope and instruments. Excellent exposure is produced by elevating the skin with hooks rather than by using carbon dioxide insufflation. This method reduces the incidence of subcutaneous emphysema and pneumomediastinum. RESULTS: Twenty-two thyroid lesions were resected using total video endoscopic surgery (adenoma, 13; cancer, 5; benign cyst, 3; and Graves' disease, 1). Procedures included thyroidectomy (12), thyroidectomy and isthmusectomy (4), and subtotal thyroidectomy (2). Subtotal cervical adenectomy was performed in 3 patients with papillary carcinoma. Cosmetic results were excellent. CONCLUSION: Endoscopic surgery of the neck is safe, minimally invasive, and produces excellent cosmetic results. However, it is in an early stage of development. Techniques have yet to be standardized, and specialized instruments are not available. The field is likely to mature as surgeons gain more experience.

Adenoma↗
PubMed2001

Molecular bases of odor discrimination: Reconstitution of olfactory receptors that recognize overlapping sets of odorants.

The vertebrate olfactory system discriminates a wide variety of odorants by relaying coded information from olfactory sensory neurons in the olfactory epithelium to olfactory cortical areas of the brain. Recent studies have shown that the first step in odor discrimination is mediated by approximately 1000 distinct olfactory receptors, which comprise the largest family of G-protein-coupled receptors. In the present study, we used Ca(2+) imaging and single-cell reverse transcription-PCR techniques to identify mouse olfactory neurons responding to an odorant and subsequently to clone a receptor gene from the responsive cell. The functionally cloned receptors were expressed in heterologous systems, demonstrating that structurally related olfactory receptors recognized overlapping sets of odorants with distinct affinities and specificities. Our results provide direct evidence for the existence of a receptor code in which the identities of different odorants are specified by distinct combinations of odorant receptors that possess unique molecular receptive ranges. We further demonstrate that the receptor code for an odorant changes with odorant concentration. Finally, we show that odorant receptors in human embryonic kidney 293 cells couple to stimulatory G-proteins such as Galphaolf, resulting in odorant-dependent increases in cAMP. Odor discrimination is thus determined by differences in the receptive ranges of the odorant receptors that together encode specific odorant molecules.

Animals↗
PubMed2001

Reduced expression of hepatocyte growth factor activator inhibitor type-2/placental bikunin (HAI-2/PB) in human glioblastomas: implication for anti-invasive role of HAI-2/PB in glioblastoma cells.

Hepatocyte growth factor activator inhibitor type-2/placental bikunin (HAI-2/PB) is a serine proteinase inhibitor that contains 2 Kunitz-domains and a presumed transmembrane domain. It has broad inhibitory spectra against various serine proteinases showing potent inhibitory activities not only to hepatocyte growth factor activator but also to plasmin, trypsin and kallikreins. In this study, we investigated the expression of HAI-2/PB in human gliomas in vivo and the effects of HAI-2/PB on the fibrinolytic and invasive capabilities of human glioblastoma cells in vitro. With RNA blot analysis, HAI-2/PB mRNA was expressed in normal brain and in low-grade astrocytomas, but was hardly detectable in anaplastic astrocytomas and glioblastomas, indicating that its expression levels were inversely correlated with the histological grade of human gliomas. To further explore the possible role of HAI-2/PB in glioma progression, cultured human glioblastoma cell lines (U251 and YKG-1) were transiently transfected with an expression vector harboring human HAI-2/PB cDNA. Subsequent analysis indicated that the expression of HAI-2/PB suppressed the fibrinolytic activities of both glioblastoma cell lines. Moreover, HAI-2/PB inhibited Matrigel invasion of U251 and YKG-1 cells by 30% and 64%, respectively. This anti-invasive effect appeared to be mediated primarily by the inhibitory activity of HAI-2/PB against the serine proteinase-dependent matrix degradation. These findings suggest that the reduced expression of HAI-2/PB is possibly involved in the progression of human gliomas.

Astrocytoma↗
PubMed2001

Functional blockade of platelet-derived growth factor receptor-beta but not of receptor-alpha prevents vascular smooth muscle cell accumulation in fibrous cap lesions in apolipoprotein E-deficient mice.

BACKGROUND: The vascular smooth muscle cell (VSMC) is the central cell component involved in the fibroproliferative response in atherogenesis. As the lesion advances, VSMCs migrate from the media into the subendothelial space, thereby forming fibrous plaque lesions. Platelet-derived growth factor (PDGF) has been known to be a potent chemoattractant and mitogen for SMCs, but the pathophysiological role of the 2 PDGF receptors, receptor-alpha (PDGFR-alpha) and receptor-beta (PDGFR-beta) in atherogenesis is poorly understood. To clarify this problem, we prepared antagonistic rat monoclonal antibodies, APA5 and APB5, against murine PDGFR-alpha and PDGFR-beta, respectively. METHODS AND RESULTS: Apolipoprotein E-deficient mice were fed a high-fat diet containing 0.3% cholesterol from 6 weeks of age and subjected to injection with 1 mg/d IP of either antibody from 12 to 18 weeks every other day. In the mice injected with APB5, the aortic atherosclerotic lesion size and the number of intimal VSMCs were reduced by 67% and 80%, respectively, compared with the control mice injected with irrelevant rat IgG. In contrast, the mice that received APA5 showed only minimal reduction of lesion size, and a large number of VSMCs were observed in the intima. In the intima of advanced lesions, APB5 immunolabeled VSMCs, whereas APA5 could detect VSMCs mainly in the media. CONCLUSIONS: These results indicate that PDGFR-beta plays a significant role in formation of fibrous atherosclerotic lesions and that regulation of the signal transduction through PDGFR-beta could affect atherogenesis in mice.

Animals↗
PubMed2001

Mouse hepatocyte growth factor activator inhibitor type 1 (HAI-1) and type 2 (HAI-2)/placental bikunin genes and their promoters.

Hepatocyte growth factor (HGF) activator inhibitor type 1 (HAI-1) and type 2 (HAI-2) were recently discovered as specific inhibitors of HGF activator. Each of them contains two Kunitz-type serine protease inhibitor domains and a transmembrane domain, so that their overall structures are similar to each other. In this study, mouse genes encoding HAI-1 and HAI-2 were cloned by screening of a mouse genomic bacterial artificial chromosome library and by polymerase chain reaction of mouse genomic DNA, respectively. The genes (mHAI-1 and mHAI-2) were defined to consist of 11 and eight exons spanning 11 kbp and 9.5 kbp, respectively. Neither a TATA nor CAAT box was found in 5'-flanking regions of both genes and no apparent homologous portion was observed between mHAI-1 and mHAI-2 promoter regions. Promoter assay of mHAI-1 and human HAI-1 revealed that the potential binding sites of a complex of Egr-1-3 and Sp1, which was well-conserved between human (-42 to -58) and mouse (-44 to -57), might be a key portion of its transcriptional regulation to function as not only house-keeping but also early responsive genes.

Animals↗
PubMed2001

AG-041R, a gastrin/CCK-B antagonist, stimulates chondrocyte proliferation and metabolism in vitro.

A newly synthesized compound, AG-041R, 3R-1-(2,2Diethoxyethyl)-3-((4methylphenyl) amino-carbonylmethyl)-3-((4methylphenyl)ureido-indoline-2-one), is a cholecyctokinin-B/gastrin receptor antagonist, but unexpectedly magnified cartilage formation in vivo. Indeed, AG-041R is a potentially effective reagent for the repair of articular cartilage defects. To clarify its effects on chondrocytes, we studied the proliferation, matrix formation, and gene expression of rabbit primary chondrocytes cultured in type I collagen gel composites with AG-041R. Both proliferation and glycosaminoglycan synthesis were stimulated with 1 microM AG-041R, but suppressed with 10 microM. The ratio of the amounts of two chondroitin sulfate isomers, chondroitin-6-sulfate to chondroitin-4-sulfate (an indicator of cartilage maturation), increased with 1 microM but decreased with 10 microM AG-041R. Gene expression analysis showed there was no change in the relative expression levels of chondrocyte markers, Type II collagen and Aggrecan, and osteoblast and adipocyte markers, Type I collagen and PPARgamma, respectively. These findings suggest that adequate concentrations of AG-041R stimulate proliferation of chondrocytes in the matrix, without changing their differentiated characteristics.

Aggrecans↗
PubMed2001

Chronic treatment with amlodipine modulates adrenocortical angiotensin II receptors in spontaneously hypertensive rats.

We investigated the effects of long-term treatment with calcium-antagonist, amlodipine, on angiotensin II receptors in the adrenal cortex of spontaneously hypertensive rats (SHR). Seven-week-old male SHR were treated with oral amlodipine (10 mg/kg/day) or vehicle (saline) for four weeks. Age-matched normotensive Wistar-Kyoto (WKY) rats were treated with the vehicle similar to control SHR. Systolic blood pressure (SBP) showed time-dependent increase in SHR but not in WKY rats, while amlodipine treatment significantly reduced the high SBP in SHR. Plasma renin activity was serially increased in SHR, which was further enhanced by amlodipine treatment. But the plasma aldosterone level which was increased in SHR was not changed by amlodipine. Competitive reverse transcriptase-polymerase chain reaction showed that the level of adrenocortical angiotensin II type 1 receptor (AT1R) mRNA progressively decreased in vehicle-treated SHR compared to WKY rats and that 4-week course of amlodipine treatment significantly increased AT1R mRNA in SHR to levels comparable to those in WKY rats. Amlodipine treatment reduced the level of adrenocortical angiotensin II type 2 receptor (AT2R) mRNA in SHR from 8 weeks of age. Thus, chronic amlodipine treatment differently modulates both adrenocortical AT1R and AT2R in SHR in a possibly direct manner.

Adrenal Cortex↗
PubMed2001

Amyloid beta protein precursor is involved in the growth of human colon carcinoma cell in vitro and in vivo.

Amyloid beta protein precursor (APP) is a membrane-bound protein ubiquitously expressed in a variety of types of cells. However, its biological functions remain largely uncertain, particularly in non-neural cells and tumors. Our previous studies revealed that a secreted form of APP having a Kunitz-type inhibitor domain is a major serine proteinase inhibitor secreted by human colon carcinoma cells. In our study, we used an antisense RNA strategy to selectively inhibit the expression of APP in the human colon carcinoma cell line SW837. A vector capable of expressing an antisense mRNA complementary to 911 bases of the 5' end of APP mRNA was transfected into SW837 cells. After selection, 2 stably transfected antisense clones were obtained in which both the APP protein and mRNA were significantly suppressed. The proliferative potential and colony-forming efficiency of the antisense clones in vitro were markedly suppressed compared with the parent and mock-transfected clones. The addition of the conditioned medium of parent cells or purified secretory APP enabled these antisense effects to be overcome in vitro. The suppressed growth was also observed in vivo when the cells were injected subcutaneously into nude mice. Histologically, formation of tubular structures appeared to be suppressed in the antisense clones in vivo. These observations suggest potentially important roles of APP in cellular proliferation and differentiation of colon carcinoma cells.

Amyloid beta-Protein Precursor↗
PubMed2001

Developmental profile of the changes in the prothoracicotropic hormone titer in hemolymph of the silkworm Bombyx mori: correlation with ecdysteroid secretion.

A very sensitive time-resolved fluoroimmunoassay for the prothoracicotropic hormone (PTTH) of the silkworm Bombyx mori has been established. The lower limit of detection in this assay was 0.1 pg. With this assay method, the amounts of PTTH in the central nervous system and hemolymph were quantified. PTTH was detected only in the brain within the central nervous system, and, in the fifth instar, its content in the brain increased gradually with larval growth and decreased rapidly after the beginning of wandering. A substantial amount of PTTH was also found in the retrocerebral complex of day-3 fifth instar larvae, accounting for 28% of total PTTH. The PTTH titer in hemolymph changed dramatically during Bombyx development, with a small peak in the middle of the fourth instar, medium-sized peaks at the wandering and prepupal stages in the fifth instar, and a large prolonged peak during early pupal-adult development. The changes were overall closely correlated with those in hemolymph ecdysteroid titer. However, some unexpected aspects of PTTH dynamics in hemolymph have also been disclosed. Based on these observations, the significance of PTTH secretion in the control of insect development is discussed.

Animals↗
PubMed2001

Alpha-fetoprotein producing gastric cancer lacks transcription factor ATBF1.

Alpha-fetoprotein (AFP) producing gastric cancer (AFP-GC) is very malignant and highly metastatic compared with common gastric cancer. However, the causal relationship between AFP production and the high malignancy of AFP-GC is unclear. We investigated AFP gene regulation in AFP-GC by an active transcription factor, HNF1 (hepatocyte nuclear factor 1) and a repressive transcription factor, ATBF1 (AT motif binding factor 1). RNase protection assays revealed that the production of AFP in gastric cancer cells did not directly associate with HNF1 expression. An inverse relation between the expressions of ATBF1 and AFP was clearly observed in gastric cancer cells. CAT assays showed the direct inhibition of AFP gene expression by ATBF1. Methylation analysis of the AFP promoter region in gastric cancer cells suggested that methylation itself could not explain the silencing of the AFP gene. Immunohistochemistry of resected clinical samples revealed that AFP producing cells lacked ATBF1 immunoreactivity. Our data suggests that the absence of ATBF1 is responsible for AFP gene expression in gastric cancer, and the absence of ATBF1 is a distinct characteristic of AFP-GC and might be important for its highly malignant nature.

DNA Methylation↗
PubMed2001

High-performance liquid chromatographic analysis of the sulfation of 4-hydroxypropranolol enantiomers by monkey liver cytosol.

We developed a new high-performance liquid chromatographic method using an ODS column and a chiral column for the assay of racemic 4-OH-PL sulfate and enantiomeric 4-OH-PL sulfates, respectively. The method was successfully applied to measure phenolsulfotransferase (PST) activities for 4-OH-PL in cytosolic fractions from livers of Japanese monkeys (Macaca fuscata) and for comparison with its activity of cytosolic fractions from rat, rabbit, dog, and human livers and Hep G2 cells. The activity was ranked as Hep G2 cells > monkeys = humans = dogs = rats > rabbits. To evaluate the Japanese monkey as a nonhuman animal model in drug metabolism studies, we further characterized sulfation of 4-OH-PL as a further metabolic pathway in monkey livers to compare that with human livers. Inhibition studies in which cytosolic fractions were preincubated at 43 degrees C or 2,6-dichloro-4-nitrophenol (DCNP) used as a PST inhibitor indicated that two kinds of PSTs, thermolabile, low-Km and DCNP-resistant PST and thermostable, high-Km and DCNP-sensitive PST were involved in 4-OH-PL sulfation by monkey liver cytosol, which is very similar to the reported profile of 4-OH-PL sulfation by human liver cytosol. Sulfation kinetics in a low concentration range of 4-OH-PL enantiomers demonstrated that apparent Km values were similar between human and monkey liver cytosolic fractions, but the Vmax values were different, so that intrinsic clearance values (Vmax/Km, Clint) were higher in monkeys than in humans. Furthermore, enantiomer selectivity of [R(+)-4-OH-PL > S(-)-4-OH-PL] was observed in the Vmax and CLint values of monkey liver cytosol. These results indicate that the profile of sulfation of 4-OH-PL by liver cytosolic fractions is similar in humans and Japanese monkeys.

Adult↗
PubMed2001

The role of nitric oxide and the renin-angiotensin system in salt-restricted Dahl rats.

To elucidate the role of nitric oxide (NO) and renin-angiotensin system (RAS) in the development of salt-sensitive hypertension, we investigated the pressor responses and renal histologic changes after long-term inhibition of endogenous NO synthesis in Dahl-Iwai salt-sensitive (DS) and salt-resistant (DR) rats under salt-re-stricted conditions that exaggerate RAS activation. Male DS and DR rats (6 weeks old) were fed with a low-salt (0.3%) diet for 5 weeks. NG-nitro-L-arginine (L-NA; dissolved in 60 mg/L deionized water), an arginine analogue acting as a NO-inhibitor, was also administered for 5 weeks. L-NA administration induced a gradual increase in systolic blood pressure (SBP) in both strains, and the pressor response in DS rats was apparently more enhanced relative to that in DR rats. Urinary nitrate plus nitrite (u-NOx) excretion was decreased by L-NA, with a significant negative correlation between SBP and u-NOx excretion in DS rats but not in DR rats. Plasma renin activity and urinary aldosterone level were significantly increased in L-NA-treated DS rats on week 5. Marked histologic changes with glomerular sclerosis and increased proteinuria and urinary N-acetyl-beta-glucosaminidase excretion were found in L-NA-treated DS rats but not DR rats. Competitive RT-PCR of mRNA extracted from the glomeruli revealed that angiotensin II type 1 receptor (AT1R) mRNA level was significantly lower in DS rats than in DR rats at week 2, and that L-NA administration significantly reduced glomerular AT1R level of DS rats at week 5, possibly because of downregulation. Our results showed that, even under sodium restriction, the pressor response and renal injury induced by chronic NO inhibition were markedly more enhanced in DS rats than in DR rats, which indicates that depletion of NO participates in both the development of hypertension and glomerular injury in DS rats through a potential activation of RAS irrespective of sodium loading. These data suggest that endogenous NO is an essential determinant of salt-sensitive hypertension in DS rats.

Aldosterone↗
PubMed2001

The effects of transplantation of osteoblastic cells with bone morphogenetic protein (BMP)/carrier complex on bone repair.

We investigated the effects of transplantation of osteoblastic cells with a bone morphogenetic protein (BMP)/carrier complex on bone repair by in vitro and in vivo experiments. Poly-D,L-lactic-co-glycolic acid/gelatin sponge (PGS) was used as a carrier for cell transplantation. In the in vitro experiments, three cell types, C3H10T1/2 cells, MC3T3-E1 cells, and primary osteoblastic cells, isolated from newborn rat calvariae (ROB cells), were cultured for 2 weeks on PGS alone or PGS containing BMP-2 (PGS/BMP). C3H10T1/2 cells cultured on PGS/BMP expressed several markers related to differentiation of both osteoblasts and chondrocytes, such as alkaline phosphatase (ALP) activity and mRNAs for osteocalcin and aggrecan, whereas the cells cultured on PGS alone expressed no such markers. MC3T3-E1 cells cultured on PGS/BMP exhibited a more ALP-positive cells than those cultured on PGS alone. PGS/BMP promoted ROB cell differentiation into both osteoblasts and chondrocytes. In the in vivo experiments, we transplanted ROB cells, which had been cultured on PGS alone or PGS/BMP in vitro for 2 weeks, into bone defects created in rat calvariae. Transplantation of ROB cells cultured on PGS alone generated little new bone. Transplantation of ROB cells cultured on PGS, which absorbed a low dose (10 ng) of rhBMP-2,; induced significantly higher bone mineral content than PGS/BMP alone, although application of a high dose (1 microg) of rhBMP-2 induced no difference in bone mineral content between transplantation of PGS/BMP with or without ROB cells. These results show that transplantation of osteoblastic cells after induction of osteoblast maturation in vitro by cultivation on PGS/BMP is a potent technique for cell therapy of bone repair.

Aggrecans↗
PubMed2001

Primary cutaneous Langerhans cell histiocytosis showing malignant phenotype in an elderly woman: report of a fatal case.

BACKGROUND: Langerhans cell histiocytosis (LCH) is a proliferating disorder of Langerhans cells (LC) that are characterized by the presence of Birbeck granules. LCH has been considered to be a disease of childhood and there have been limited cases of adult LCH. We report here a fatal case of histiocytic tumor showing Langerhans cell phenotype, arising in the skin of a 74-year-old woman. METHOD: In addition to routine histological and immunohistological sections, electron microscopic examination and human androgen receptor gene (HUMARA) assays were performed. RESULTS: Histological examination revealed a dense dermal infiltrative proliferation of fairly large tumor cells with abundant ill-defined cytoplasms and oval or indented nuclei, in which numerous eosinophils were associated with the tumor nests. Tumor cells were positive with anti-S-100 and CD1a antibodies but negative with HMB-45 antibody or other epithelial or lymphocytic markers. Ultrastructural analysis showed typical Birbeck granules in the cytoplasm of the tumor cells. HUMARA assay of the tumor tissue revealed the nonrandom X inactivation pattern, indicating the clonal proliferation. CONCLUSIONS: We diagnosed this tumor as Langerhans cell histiocytosis with a clonal neoplastic phenotype originated in the skin. Although she demonstrated no recurrence nor metastases for 6 months after surgical resection of primary skin lesion and subsequent radiation therapy, the tumor recurred and extended multisystemically, and she died of multiple organ failure 14 months after initial diagnosis. Therefore, we would like to emphasize this case as LC "sarcoma" or "malignant" LCH.

Aged↗
PubMed2001

Solitary fibroleiomyomatous hamartoma of the lung in a patient without a pre-existing smooth-muscle tumor.

A solitary well-demarcated tumor was found in the left lung of a 53-year-old man. It was located in the posterior region of the lower lobe just adjacent to, but apart from, the pleura. It was resected by video-associated thoracic surgery. Macroscopically, the tumor was a whitish solid nodule without hemorrhage or necrosis, and it was 1.5 cm in diameter. Histologically, the tumor consisted of a proliferation of fibromuscular tissue in interlacing fascicles in which many tubular or cleft-like epithelial inclusions were involved. The epithelial inclusions showed cystic changes with goblet cell metaplasia in part, but no atypical changes. Other mesenchymal components such as cartilaginous, myxomatous or adipose tissues were not seen. The patient had no history of neoplasm, including smooth-muscle tumor. Thus, we diagnosed this tumor as a "true" fibroleiomyomatous hamartoma, as distinct from so-called fibroleiomyomatous hamartoma or benign metastasizing leiomyoma, which are usually found in the lungs of women who have had hysterectomies, as multiple fibromuscular nodules. We report here this rare case and we review and discuss published reports of fibromuscular tumors of the lung.

Hamartoma↗