Osteosarcoma cell apoptosis induced by selenium.

An essential nutrient selenium has been reported to be a potential cancer preventive and inhibitory agent, although no exact mechanism has yet been proposed. Since little is known about the anti-proliferative effect of selenium on osteosarcoma, this issue was addressed in the present study in vitro using three osteosarcoma cell lines, and in vivo using an osteosarcoma transplantable to nude mice. Selenium inhibited the tumor growth in vitro and morphological changes indicative of apoptosis were demonstrated. Osteosarcomas in nude mice were inhibited in growth by selenium with no cytotoxic change in normal tissues. The findings suggested that selenium may offer a novel therapeutic modality for osteosarcoma.

Transcriptional activation of p21 by vitamin D(3) or vitamin K(2) leads to differentiation of p53-deficient MG-63 osteosarcoma cells.

p21 (WAF1/CIP1) is a downstream effector of p53 and mediates growth arrest by inhibiting the action of G(1) cyclin-dependent kinases. However, it has been reported that the p21 expression was triggered by multiple differentiation-inducing agents by a p53-independent pathway. These agents induced expression of p21 by binding to specific DNA elements and modulating transcriptional initiation. We demonstrated that the gene encoding p21 was not only a vitamin D(3) target gene but also a vitamin K(2) target gene in the cells and that their differentiation was well related to the transcriptional activation of the p21 gene. Transient overexpression of p21, using adenovirus-driven p21 expression plasmid, in MG-63 cells in the absence of vitamins D(3) and K(2) resulted in their differentiation. The transcriptional activation of p21 by vitamin D(3) or vitamin K(2) in p53-deficient osteosarcoma cells demonstrated the p53-independent role of p21 in human osseous differentiation. HUM PATHOL 32:410-416.

Intraneural monophasic synovial sarcoma: a case report.

STUDY DESIGN: A case report. OBJECTIVES: To illustrate a rare case of synovial sarcoma arising within a peripheral nerve. SUMMARY OF BACKGROUND DATA: A synovial sarcoma arising within a peripheral nerve is very unusual. Only five cases of primary synovial sarcoma within a peripheral nerve have been reported. This is the first case with involvement of the nerve root. The authors diagnosed the tumor arising within the S1 nerve root as synovial sarcoma using cytogenetic analysis that detected the chimeric SYT/SSX gene. METHODS: In addition to the immunohistochemical study, a reverse transcription-polymerase chain reaction (RT-PCR) assay was conducted for the SYT-SS10 fusion gene using archival formalin-fixed paraffin-embedded tumor specimens. RESULTS: Computed tomography scan, magnetic resonance imaging performed before surgery, and the intraoperative findings showed that the tumor was embedded within the S1 nerve root. Although the histologic findings were suggestive of a malignant peripheral nerve sheath tumor, the results of the cytologic study confirmed its diagnosis of synovial sarcoma. CONCLUSION: Primary intraneural synovial sarcoma, although rare, must be distinguished from malignant peripheral nerve sheath tumor. The molecular assay of the detection of the SYT/SSX fusion gene is useful to make a definite diagnosis of monophasic synovial sarcoma.

Increased concentrations of nitrate and nitrite in the cyst fluid suggesting increased nitric oxide synthesis in solitary bone cysts.

The etiology and treatment of a solitary bone cyst have remained undefined. Surgical treatments have not been encouraging, because a less invasive corticosteroid-injection treatment has afforded good results. However, there has been little scientific rationale supporting corticosteroid treatment. In recent reports, bone-resorbing factors, including matrix metalloproteinases, prostaglandins, interleukin-1, and oxygen free radicals, have been demonstrated in the cyst fluid. To better elucidate the pathophysiology of the solitary bone cyst, we examined the activities of nitric oxide and cytokines in the cyst fluid as well as in the cyst membrane. The levels of nitrate and nitrite were significantly higher in the cyst fluid than in serum. Immunostaining of cells in the stroma and lining cells of the cyst wall was strongly positive for inducible nitric synthase. The levels of interleukin-6 and interleukin-1beta in the cyst fluid were elevated, and cells in the cyst membrane were positive for tumor necrosis factor-alpha, interleukin-6, and interleukin-1beta. Cultured cells from the cyst membrane were induced in the production of nitrate and nitrite in response to cytokine treatment. These findings suggest that the solitary bone cyst was in a state favorable for the production of nitric oxide.

A solitary bone cyst in the spinous process of the cervical spine: a case report.

STUDY DESIGN: A case report. OBJECTIVES: To illustrate a rare case of histologically confirmed solitary bone cyst involving the spinous process of C7. SUMMARY OF BACKGROUND DATA: A solitary bone cyst involving the spine is very unusual. Although four cases of a solitary bone cyst in the spine have been reported in the literature, the current authors have been able to find only one case of solitary bone cyst in the spinous process. All four patients reported in the literature were over 30 years of age. The patient in the current case was a 13-year-old girl with no history of trauma. METHODS: Radiographs and a computed tomography scan of the cervical spine were performed before the operation, as was a histologic examination to make a diagnosis of the lesion. RESULTS: The intraoperative findings from examination of the stagnant fluid within the lesion and the histologic examination indicated the diagnosis of a solitary bone cyst. CONCLUSIONS: A solitary bone cyst in the spine is rare, especially in the young. An osteolytic lesion in the spinous process of the spine tends to be diagnosed as an osteoblastoma or as a giant cell tumor of the bone. A solitary bone cyst of the spine, although rare, must be considered as a differential diagnosis.

p21 and parathyroid hormone-related peptide in the growth plate.

It is essential for terminal chondrocytes to die before the conversion of calcified cartilage to bone. We have previously demonstrated that apoptosis occurred in the terminal hypertrophic chondrocyte of the growth plate. However, the essential mechanism by which the differentiation of chondrocytes is regulated has not yet been characterized. The purpose of this study was to investigate the mechanism for regulating chondrocyte differentiation. We focused on PTHrP and p21 which regulated the differentiation of chondrocytes and investigated how these factors interacted with each other in chondrocyte differentiation in the growth plate. PTHrP was strongly positive on immunostaining at the interface between the proliferating and the upper zone of the hypertrophic chondrocytes, whereas p21 was negative. On the other hand, p21 was positive in the lower zone of hypertrophic chondrocytes. Furthermore, PTHrP up-regulated the cell proliferation and down-regulated the expression of the p21 messengers in SW-1353 chondrosarcoma cells. These findings indicated that PTHrP might be a negative regulator for p21 in the differentiation of chondrocytes.

Modulation of fas-mediated apoptosis in osteosarcoma cell lines.

Fas/APO-1 (or CD95) is a 45-kDa cell surface glycoprotein that transduces cellular death signals for apoptosis upon cross-linking with the Fas ligand, which is experimentally replaced by anti-Fas antibodies. We examined the Fas expression at the protein and mRNA levels, and susceptibility to anti-Fas-mediated apoptosis, in 14 osteosarcoma cell lines. Ten of 14 ostesarcoma cell lines constitutively expressed detectable levels of Fas on the cell surface with positive cell rates ranging from 10.2 to 72.4%. Four other cell lines expressed Fas almost exclusively in the cytoplasm. An antibody against Fas was able to induce Fas-mediated cell death only in two cell lines with high levels of surface Fas. In the presence of the protein synthesis inhibitor cyclohexamide, antibody to Fas led to an induction of apoptosis in ten of the osteosarcoma cell lines antibody-concentration dependently. These data suggest that Fas is a potential protein related to apoptosis in osteosarcomas when the sensitizing activity of cyclohexamide on anti-Fas-mediated cytotoxicity was exerted.

Efficacy of aquatic exercises for patients with low-back pain.

We have studied 35 patients (25 female and 10 male) with low-back pain who were managed with aquatic exercises after an appropriate period of treatment for their condition in the medical institution. The exercises employed consisted of strengthening exercises for the abdominal, gluteal, and leg muscles, stretching of the back, hip, hamstrings, and calf muscles, walking in water, and swimming. All the patients had been participating in the exercise program for more than 6 months. The frequency of performing exercises was once a week for 7 patients, twice a week for 19, and 3 or more times a week for the remaining patients. The method used in this study was a survey questionnaire which was composed of questions about the patient's physical and psychological condition. Those patients who had performed exercises twice or more in a week showed a more significant improvement in the physical score than those who performed exercises only once a week. More than 90% of the patients felt they had improved after 6 months of participation in the program. The improvement in physical score was independent of the initial ability in swimming. The results obtained suggested that exercises in water may be one of the most useful modes of exercise for a patient with low-back pain.

Bone tumors in the pelvis presenting growth during pregnancy.

Among 56 cases of a giant cell tumor of bone (GCT) and 52 cases of chondrosarcoma (CSA) in our series, four patients were discovered to have a tumor in the pelvic bone that grew in size during pregnancy. These four rare cases are described here. They include three cases of a GCT in the sacrum and one case of a CSA in the innominate bone. The dextran-coated charcoal assay and immunohistochemical techniques demonstrated the independence of these tumors from hormonal regulation despite the growth stimulated during pregnancy. It was concluded that the delay in detection of these tumors in the pelvis was just related to the opportunity afforded for unexpected growth during pregnancy. Surgical management was difficult due to the delay in tumor detection. The initial complaints such as pain, discomfort, or numbness around the pelvis were misinterpreted as symptoms of pregnancy. It should be kept in mind that during pregnancy, any pain or numbness in the pelvic region could be the direct result of a tumor in the pelvic bone.

IL-6 in a pleomorphic type of malignant fibrous histiocytoma presenting high fever.

We describe a rare case of pleomorphic type of malignant fibrous histiocytoma (MFH) in the buttock that presented a systemic involvement. The case was of a 58-year-old woman presenting hepatic dysfunction and inflammatory reactions including fever, positive C-reactive protein (CRP), an elevated erythrocyte sedimentation rate, and high levels of platelets and ferritin. The fever of 3 months duration subsided on the first postoperative day. The MFH resection also brought rapid normalization in CRP, platelets, and leukocytes. The local and systemic productions of cytokines induced by this tumor were evaluated. In vivo and in vitro production of interleukin (IL)-6, IL-1beta, and tumor necrosis factor alpha by tumor cells were measured using enzyme-linked immunosorbent assay. Blood samples taken preoperatively, tumor tissues, and the primary culture medium showed extraordinarily high IL-6 levels. The plasma IL-6 level was normalized postoperatively. Immunohistochemistry showed the positivity of tumor cells for IL-6. The IL-6 produced by the tumor was concluded to have been responsible for the systemic illness.

Morphological and biochemical evidence for apoptosis in the terminal hypertrophic chondrocytes of the growth plate.

The purpose of this study was to investigate the mechanism of cell death in chondrocytes of the growth plate. In the degenerative chondrocyte zone of the growth plate, apoptotic chondrocytes were defeated by the in situ nick end labelling method, by DNA analysis in agarose gel, and by electron microscopy. The results of the in situ nick end labelling method and the occurrence of a ladder pattern of DNA in agarose gel analysis indicated the activation of endogenous endonucleases, resulting in DNA fragmentation. Electron micrographs showed the early morphological changes associated with apoptosis. This report presents both morphological and biochemical evidence for apoptosis in the terminal hypertrophic chondrocytes of the growth plate. These data suggest that apoptosis of degenerative chondrocytes may play an important role in the control of normal and pathological endochondral ossification.

Interleukin-4 stimulates rheumatoid synovial fibroblasts to express matrix metalloproteinase-1 (tissue collagenase) and histamine H1 receptor mRNA.

In the present study, we investigated the effect of interleukin-4 (IL-4) on metalloproteinase 1 (MMP-1/tissue collagenase) production in human rheumatoid synovial fibroblasts. Northern blot analysis revealed that addition of IL-4 with or without histamine stimulated the cells to increase the amount of proMMP-1 mRNA, and the IL-4 with histamine addition resulted in a 3.3-fold increase compared with histamine only. Furthermore, IL-4 itself stimulated the expression of histamine H1 receptor mRNA. These results suggest that IL-4 may play an important role in joint destruction in RA.

Histamine-stimulated production of matrix metalloproteinase 1 by human rheumatoid synovial fibroblasts is mediated by histamine H1-receptors.

The purpose of this study was to investigate the role of histamine in human rheumatoid synovial fibroblasts in the production of factors responsible for tissue remodelling and cartilage breakdown in rheumatoid arthritis. We examined the effects of histamine of tritiated thymidine incorporation, production of matrix metalloproteinase-1 (MMP-1), histamine H1-receptor expression, phosphoinositide metabolism and intracellular calcium ion concentration ([Ca2+]i) in human rheumatoid synovial fibroblasts. Tritiated thymidine incorporation studies demonstrated that histamine markedly stimulated the proliferation of rheumatoid synovial fibroblasts. Immunofluorescence and Northern blot analyses revealed that proMMP-1 production was also stimulated by histamine. The levels of inositol phosphates and [Ca2+]i in the cells were elevated in response to histamine, indicating that the cells expressed histamine H1-receptors; and Northern blot analysis indicated that these H1-receptors were up-regulated by histamine. In in situ hybridization, large amounts of histamine H1-receptor mRNA were also detected in rheumatoid synovial tissue. These results suggest that the interaction between H1-receptor expression in rheumatoid synovial fibroblasts and histamine secretion by mast cells and macrophages in the affected sites is an important event responsible for tissue remodelling and joint destruction in rheumatoid arthritis.

Effects of lipid peroxide on production of matrix metalloproteinase 1 (tissue collagenase) and 3 (stromelysin) and tissue inhibitor metalloproteinase 1 by human rheumatoid synovial fibroblasts.

The effects of linoleic acid hydroperoxide on the production of matrix metalloproteinases (MMPs) including MMP-1 (tissue collagenase), -2 ("type IV collagenase"), and -3 (stromelysin) and of tissue inhibitor of metalloproteinase 1 (TIMP-1), as well as DNA synthesis were investigated in rheumatoid synovial fibroblasts. Our results demonstrated that the levels of proMMP-1 and -3 and TIMP-1 were extremely elevated when 0.5-2.0 nmole/ml of linoleic acid hydroperoxide was added to cultures of rheumatoid synovial fibroblasts. DNA synthesis, however, was inhibited by linoleic acid hydroperoxide. These results indicate that lipid peroxide causes the disruption of extracellular matrix macromolecules and the inhibition of cell repair in synovial tissue. Therefore, they also suggest that an elevated level of oxygen free radical and/or lipid peroxides in synovial fluid may play an important role in the process of rheumatoid arthritis, resulting in the disruption of the joint.