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Biomedical subjects

Toshiaki Hitora

Publications and source records attributed to Toshiaki Hitora.

At least 19 recordsLinked to original sources
PubMed2005

Establishment and characterization of a KIT-positive and stem cell factor-producing cell line, KTHOS, derived from human osteosarcoma.

Osteosarcoma is a malignant bone tumor that commonly affects adolescents and young adults. In the present study a human osteosarcoma cell line, KTHOS, was established from a primary osteosarcoma lesion in the distal femur of a 16-year-old girl. After 106 passages, the KTHOS cell line retained the biological characteristics of osteosarcoma. The KTHOS cells had spindle to pleomorphic cytoplasm with round to ovoid nuclei containing multiple prominent nucleoli, as expected based on the mesodermic origin of osteoblasts. The KTHOS cells were immunoreactive for osteocalcin, osteonectin, stem cell factor (SCF), and KIT (CD117). Reverse transcriptase-polymerase chain reaction indicated that the KTHOS cell line expressed mRNA for SCF and KIT. The KTHOS cells produced relatively high amounts of soluble SCF as determined by enzyme-linked immunosorbent assay. The results suggest that cell proliferation of the KTHOS cell line might be involved in autocrine and/or paracrine loops of the SCF/KIT signaling system. The KTHOS cell line is a novel human osteosarcoma cell line that releases SCF and expresses KIT. This cell line can be used for studies to explore the mechanisms for oncogenesis of human osteosarcomas.

Adolescent↗
PubMed2004

Expression of transforming growth factor beta isoforms and their receptors in malignant fibrous histiocytoma of soft tissues.

PURPOSE: Transforming growth factor beta (TGF-beta) is a multifunctional growth factor that variably affects proliferation, differentiation, and extracellular matrix formation. Little information is currently available on the TGF-beta expression in malignant fibrous histiocytoma (MFH). The aims of the present study were to investigate the expression of TGF-beta isoforms and their receptors in human MFH specimens. EXPERIMENTAL DESIGN: The expression of TGF isoforms, and TGF-beta receptors (TGF-beta R1 and -beta R2) were immunohistochemically evaluated in 43 paraffin-embedded MFH specimens. Furthermore, the correlation of the TGF-beta and receptor expression with tumor proliferative activity assessed by MIB-1 indices was analyzed. RESULTS: Positive immunoreactivity for TGF-beta1, -beta2, and -beta 3 was identified in tumor cells of 42, 40, and 38 of the 43 MFHs, respectively. In each TGF-beta isoform immunostaining, the specimens were divided into two groups based on the number of positive tumor cells: those with low (<25%) and those with high (>==25%) immunoreactivity. There were no statistically significant differences in the MIB-1 indices between the two groups. Positive immunoreactivity for TGF-beta R1 and -beta R2 was identified in tumor cells of 36 and 24 of the MFHs, respectively. The specimens were divided into two groups based on their receptor expression patterns: those with both TGF-beta R1- and -beta R2-positive immunoreactivity (n = 23), and those with both or either TGF-beta R1- and -beta R2-negative immunoreactivity (n = 20). The MIB-1 indices in the both-TGF-beta R1- and -beta R2-positive group were significantly higher than those in the other group (P = 0.0102). There was no significant difference in pulmonary metastasis ratios between the two groups. CONCLUSIONS: These findings strongly suggest an association of the TGF-beta ligand/receptor system with a significantly higher MIB-1 index in human MFHs. Investigation of the TGF-beta R1 and -beta R2 coexpression might be useful in predicting tumor behavior of MFHs.

Activin Receptors, Type I↗
PubMed2004

Apophysitis of the ischial tuberosity mimicking a neoplasm on magnetic resonance imaging.

We present multimodality imaging features of an ischial tuberosity apophysitis in a 13-year-old boy who was an active baseball pitcher. Roentgenography of the pelvis and computed tomography showed mild irregularity in the inferior margin of the left ischial tuberosity. T1-weighted MRI showed a wide area with low signal intensity in the left ischial body; T2-weighted fat-suppression images showed areas with markedly high signal intensity in the ischial apophysis and body and the surrounding periosteum; contrast-enhanced T1-weighted fat-suppression MRI showed that the ischial body, surrounding periosteum, and origin of the hamstring muscles strongly enhanced; technetium-99m scintigraphic scans showed increased isotope uptake in the entire ischial body. Histological specimens obtained from the bone showed increased osteoblastic activity, edema, and proliferation of benign spindle cells and small vessels in the bone marrow spaces. In the present case, because MR imaging demonstrated extensive signal abnormalities involving the apophysis, periosteum, and intramedullary portion of bone, a neoplasm could not be excluded, and a biopsy was undertaken.

Athletic Injuries↗
PubMed2004

Periosteal osteoblastoma of the distal femur.

Osteoblastomas located on the surface of the cortical bone, so-called periosteal osteoblastomas, are extremely rare. We report on a case of periosteal osteoblastoma arising from the posterior surface of the right distal femur in a 17-year-old man. Roentgenographic, computed tomographic, magnetic resonance imaging, and histologic features of the case are presented. Periosteal osteoblastoma should be radiologically and histologically differentiated from myositis ossificans, avulsive cortical irregularity syndrome, osteoid osteoma, parosteal osteosarcoma, periosteal osteosarcoma, and high-grade surface osteosarcoma. Although periosteal osteoblastoma is rare, this tumor should be included in the differential diagnosis of surface-type bone tumors.

Adolescent↗
PubMed2004

Coexpression of hepatocyte growth factor and its receptor c-Met correlates with high MIB-1 proliferative index in malignant fibrous histiocytoma.

Hepatocyte growth factor (HGF) is a multifunctional cytokine that variably affects cell motility, proliferation, and morphogenesis. Little information is currently available on the HGF and its receptor c-Met expression in malignant fibrous histiocytoma (MFH). We immunohistochemically investigated the HGF and c-Met expression in 43 MFH tissue specimens. Furthermore, the correlation of the HGF and c-Met expression with tumor proliferative activity assessed by MIB-1 indices was analyzed. Our results showed that positive cytoplasmic immunoreactivity for HGF and c-Met was identified in tumor cells in 36 (84%) and 20 (47%) of the 43 MFH cases analyzed, respectively. Coexpression of HGF and c-Met was observed in 20 (47%) of the 43 MFHs, and was correlated with high MIB-1 proliferative indices (p = 0.0446). These findings strongly indicate that the HGF/c-Met signaling system plays an important role in promoting cell proliferation of human MFHs via an autocrine loop.

Adolescent↗
PubMed2004

Neurilemmoma in the foot as a cause of heel pain: a report of two cases.

Two cases of deep-seated neurilemmoma that arose from plantar branches of the posterior tibial nerve and caused chronic heel pain are described. At the initial examination, one case was misdiagnosed as tarsal tunnel syndrome and the other was overlooked as plantar fasciitis; both cases were treated for long periods prior to operation. Deep-seated neurilemmomas in the foot can easily be overlooked and misdiagnosed as tarsal tunnel syndrome or plantar fasciitis because of the rarity, absence of palpable mass, and similarity of symptoms to those of other frequently encountered foot disorders. Magnetic resonance imaging provides the best modality for differential diagnosis. In the present cases, surgical excision of the tumors resulted in immediate and complete relief of chronic heel pain. Surgeons should consider neurilemmoma as a cause of persistent chronic heel pain despite the rarity of the disease.

Aged↗
PubMed2003

Multimodality imaging features of primary xanthoma of the calcaneus.

Secondary xanthomatous features are histologically observed in various bone lesions, but primary xanthoma of bone is rare. We present a primary xanthoma of the right calcaneus in a 51-year-old woman who had no aberrant lipid metabolism. Roentgenograms showed a small osteolytic lesion in the calcaneal triangle, partially surrounded by bone sclerosis. Computed tomographic scans of the calcaneus showed multiple osteolytic areas, with an irregular trabecular pattern in the surrounding sclerotic bone. T1-weighted magnetic resonance images showed a lesion with central low signal intensity, surrounded by a peripheral ring with high signal intensity. The entire lesion showed high signal intensity on T2-weighted images, partially surrounded by areas with low signal intensity, concordant with reactive bone sclerosis. Histologically, the lesion consisted of numerous lipid-laden histiocytes arranged in sheets, scattered multinucleated giant cells and lymphocytes, and granulation tissues. There was no evidence of pre-existing lesions. Total excision of the tumor was curative.

Bone Diseases↗
PubMed2003

Fine-needle aspiration biopsy of solid aneurysmal bone cyst in the humerus.

We report the fine-needle aspiration biopsy (FNAB) cytology findings of a solid aneurysmal bone cyst in the left humerus of a 69-yr-old woman. Radiographically, the lesion showed an extensive, relatively well-defined osteolysis in the diaphysis, with a pathologic fracture. FNAB smears of the lesion consisted of benign, mononuclear cells and numerous osteoclast-like multinucleated giant cells. Some clusters of the mononuclear cells were closely associated with dense, homogeneous, extracellular, matrix material. To our knowledge, the FNAB features of solid ABC of the long bones have not been described previously in the English-language literature. The cytologic features are indistinguishable from those of giant cell tumors of bone and brown tumors of hyperparathyroidism.

Aged↗
PubMed2003

Extraabdominal desmoid tumor in a surgical scar of a patient with Sprengel's deformity.

Patients with an extraabdominal desmoid tumor have multiple minor bone abnormalities. The authors describe a rare case of an extraabdominal desmoid tumor that developed in a scar 2 years after surgery for Sprengel's deformity of the right shoulder in an 8-year-old girl. The association between the tumor and Sprengel's deformity has never been reported previously. Antecedent surgical trauma might play a role in the development of this tumor.

Back↗
PubMed2003

Isolated suprapatellar bursitis: Computed tomographic and arthroscopic findings.

A rare case of compartmentalized suprapatellar bursitis in the left knee of an 80-year-old man is presented. Computed tomographic (CT) scans following intravenous administration of contrast media showed a cystic mass between the quadriceps tendon and the anterior surface of the femur. Multiplanar reconstruction CT scans showed a mass superior to the patella, the wall of which was enhanced. Arthroscopic examination of the knee revealed a complete suprapatellar septum that separated the suprapatellar bursa from the knee joint cavity. Surgical excision of the bursa was curative. To our knowledge, multiplanar reconstruction CT and arthroscopic features of the isolated suprapatellar bursitis have not been illustrated previously.

Aged↗
PubMed2003

Ischiogluteal bursitis: multimodality imaging findings.

Ischiogluteal bursitis is a rare, infrequently recognized condition. Two cases of ischiogluteal bursitis in an 80-year-old man and a 75-year-old woman are presented. Both patients presented with a painful buttock mass. Contrast-enhanced multiplanar reconstruction computed tomography scans revealed a lesion with peripheral enhancement inferior to the ischial tuberosity. Magnetic resonance imaging revealed a lesion with low or intermediate signal intensity on T1-weighted images. T2-weighted images revealed a lesion with high signal intensity. Postcontrast magnetic resonance imaging scans revealed peripheral enhancement of the lesion. The multimodality imaging findings of ischiogluteal bursitis have not been described previously. Ischiogluteal bursitis should be considered in the differential diagnosis of a buttock mass.

Aged↗
PubMed2003

Granulocyte colony-stimulating factor-producing undifferentiated sarcoma occurring in previously fractured femur. A case report and review of the literature.

We examined the case of a 52-year-old man presenting with a sarcoma accompanied by severe leukocytosis, which developed many years after a femoral fracture. Histologic, histochemical, immunohistochemical, and ultrastructural analysis of the tumor revealed that the sarcoma could not be classified by any of the bone or soft tissue tumor classifications currently in use. The tumor cells were isolated from surgical specimens and subcultured in vitro. The concentration of granulocyte colony-stimulating factor in the culture medium was constantly elevated to considerably high levels during 20 cell passages. A genomic study using reverse transcription-polymerase chain reaction showed that the cells retained messenger RNA expression of granulocyte colony-stimulating factor. The aberrant overexpression of granulocyte colony-stimulating factor clearly represented a paraneoplastic phenomenon of the neoplastic cells.

Cell Differentiation↗
PubMed2002

Aspiration biopsy of nodular sarcoidosis of the muscle.

The nodular form of muscular sarcoidosis is rare and the condition is often confused with a soft tissue neoplasm. We present a case of nodular muscular sarcoidosis of the right calf in a 52-yr-old woman which was diagnosed by thin-needle aspiration biopsy (TNAB). In this patient, a calf mass was the initial manifestation of sarcoidosis. Contrast-enhanced computed tomographic scans of the calf showed a mass with peripheral ring-like enhancement. T2-weighted magnetic resonance images demonstrated a mass with central hypointensity and marked peripheral hyperintensity. TNAB revealed noncaseating epithelioid cell granulomas in association with multinucleated giant cells. Combined with the radiologic findings, TNAB is considered a useful modality for the diagnosis of nodular muscular sarcoidosis.

Biopsy, Needle↗
PubMed2002

Scrape and fine-needle aspiration cytology of extraskeletal osteosarcoma.

Extraskeletal osteosarcoma is a rare malignant soft tissue tumor whose cytologic findings are infrequently reported. We describe scrape and fine-needle aspiration biopsy (FNAB) cytology findings of an extraskeletal osteosarcoma in the right shoulder of a 24-yr-old man. Initial computed tomography revealed multiple ossification foci within the lesion. After excision of the primary tumor, the tumor recurred 13 months later. Scrape smears of both the primary tumor and FNAB smears of the recurrent tumor revealed moderate cellularity, cell clusters, and individual cells, closely associated with dense, homogeneous, acellular matrix material. The cells had elongated, oval, or partially bizarre-shaped nuclei with a coarse chromatin pattern and prominent nucleoli. The scrape smears contained large fragments of matrix material consistent with osteoid.

Adult↗