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PubMed2003

[Osteosarcoma of maxillofacial area: a clinicopathological study of 61 cases].

OBJECTIVE: To study the clinicopathology of osteosarcoma in oral and maxillofacial region. METHODS: Clinical, histopathological features of 61 cases of osteosarcoma in oral and maxillofacial region were studied. RESULTS: The ratio of male to female was 1.26:1, with the mean age 39.8. 32.8% cases were occurred in maxilla and 57.4% cases in mandible. Histologically 55.7% were osteoblastic, 16.4% were chondroblastic and 21.3% were fibroblastic. All tumors presented common histological feature that the neoplastic cells produced neoplastic bone. The recurrence rate of the tumor was 39.1% and the metastasis rate to lung was 8.7%. CONCLUSIONS: Oral and maxillofacial osteosarcoma was most frequently occurred in mandible. There was no significant difference in patient's gender. Patients were about 10 years older than those suffered the tumor in long bone. Osteoblastic type was the most commonly occurred histological type. The recurrence rate of the tumor was relatively high and the metastasis rate to lung was low. It seems that the tumor had good prognosis than osteosarcoma of long bone.

Adolescent↗
PubMed2004

Effects of TGF beta1 autocrine blockage on osteosarcoma cells.

OBJECTIVE: To evaluate the effects of transforming growth factor beta1 (TGFbeta1) autocrine blockage on proliferation activity and drug sensitivity of osteosarcoma. METHODS; Northern blot, MTT determination, and 3H thymidine incorporation were used to investigate the effects of antisense TGF beta1 gene on osteosarcoma. RESULTS: The proliferation of osteosarcoma cells transfected by antisense TGF beta1 gene was suppressed markedly, and adriamycin sensitivity was significantly increased. CONCLUSION: Blockage of osteosarcoma cells TGF beta1 autocrine loop inhibits cell proliferation and enhances chemotherapy sensitivity.

Antineoplastic Agents↗
PubMed1992

[Establishment and characterization of an ascites-forming rat osteosarcoma cell line].

A transplantable ascites-forming osteosarcoma (J. H. 1-AOS) derived from the 35th generation of spontaneous osteosarcoma, J. H. 1-OS, grown in Fischer 344 syngeneic rats was established. Tumorigenicity, histochemical and ultrastructural characteristics were investigated. Rats carrying the ascites form osteosarcoma died of cachexia about 15 days after transplantation, 1.5-2.5 x 10(6) cells/ml of tumor cells generally being involved in the ascites and tumor nodules formed in the mesentery. After inoculation into the back subcutaneous space, tumor growth was very rapid. Small round cells were detected in the Giemsa stain smear, and although osteoid formation was histologically lacking, cell surface alkaline phosphatase activity was noted both light and electron microscopically. Polyacrylamide gel electrophoresis demonstrated that alkaline phosphatase (Al-p) extracted from this tumor was consistent with Al-p from rat fetal calvaria. Thus maintenance of osteogenic potential is suggested for these ascites osteosarcoma cells, indicating their usefulness for further studies of biological behaviors of this tumor type.

Alkaline Phosphatase↗
PubMedDate not supplied

Immunotherapy by gene transfer with plasmids encoding IL-12/IL-18 is superior to IL-23/IL-18 gene transfer in a rat osteosarcoma model.

BACKGROUND: Osteosarcomas are primary malignant tumors of bone or soft parts arising from bone-forming mesenchymal cells. Despite dramatic therapeutic advances, namely neo-adjuvant and adjuvant chemotherapy, progress is at a plateau. Cytokine-mediated gene therapy might represent a further advance in the therapy of the osteosarcoma. MATERIALS AND METHODS: We transfected UMR 108 osteosarcoma cells with different plasmids encoding IL-12, IL-23, proIL-18 and ICE (Interleukin-converting enzyme). IFN-gamma induction, which is known to induce antitumor effects mediated by the immune system, and cytotoxic effects of various cytokine combination were investigated. RESULTS: Our results show that local secretion of IL-12 by UMR 108 cells led to an induction of cytotoxic effects mediated by mononuclear cells, which were enhanced by additional administration of recombinant IL-18. In contrast to IL-18, IL-23 showed a moderate increase of IFN-gamma induction when transfected alone and could only slightly increase the IFN-gamma induction mediated by IL-12. IL-18 enhanced IFN-gamma induction when applied alone and was able to increase the IFN-gamma production that was induced by IL-12. CONCLUSION: IL-23 seems to be a less effective immuno-therapeutic for adjuvant treatment of osteosarcomas than IL-12 and IL-18, when taking only IFN-gamma induction into consideration.

Animals↗
PubMed2004

Osteosarcoma and Ewing's sarcoma in children and adolescents: retrospective clinicopathological study.

AIM: Almost 20 different prognostic factors have so far been investigated in childhood bone tumors, but apart from clinical stage the results have been inconclusive. We evaluated possible prognostic factors of malignant bone tumors in children and adolescents. METHODS: Seventy children and adolescents, who have been treated for bone sarcomas (36 with osteosarcoma and 34 with Ewing's sarcoma) at the Children's Hospital in Zagreb and the Orthopedic Clinic of the Zagreb University School of Medicine were included in the study. We analyzed 9 variables: clinical stage, patient age and sex, tumor size and location, location of metastases, chemotherapy response, concentration of lactate dehydrogenase (LDH) and erythrocyte sedimentation rate (ESR), and chondroid differentiation in osteosarcoma. RESULTS: The clinical stage was the most important prognostic factor for both type of tumors. Lactate dehydrogenase in patients with Ewing's sarcoma (p=0.033) and in patients with osteosarcoma (p=0.015) as well as erythrocyte sedimentation rate (p<0.001 and p=0.014, respectively) may also be of predictive value. CONCLUSION: Elevated erythrocyte sedimentation rate and high LDH concentration seem to be of importance in both Ewing's sarcoma and osteosarcoma, regardless of their different pathogenesis or pathohistology.

Adolescent↗
PubMed1992

Allelotype analysis in osteosarcomas: frequent allele loss on 3q, 13q, 17p, and 18q.

We have investigated the involvement of tumor suppressor genes in the genesis of osteosarcoma by analyzing allele losses at polymorphic loci in tumor tissues. Genotypes of DNA from primary osteosarcoma tissue and corresponding normal cells from 37 patients were analyzed at 58 polymorphic loci representing each autosomal chromosome arm except 5p and 20q. Allele losses were found at polymorphic loci on 36 of 37 chromosome arms analyzed. In particular, four of them showed frequencies of allele loss higher than 60%: 3q (75%); 13q (68%); 17p (72%); and 18q (64%). This result suggests that, in addition to the RB (retinoblastoma) gene on 13q and the p53 gene on 17p, at least two more tumor suppressor genes located on 3q and 18q are frequently involved in the development of osteosarcoma. The extent of allele losses as defined by fractional allelic loss among 36 tumors was diverse, from 0 to 0.64. The median fractional allelic loss value of 0.32 was much higher than those previously reported in colorectal carcinoma and breast carcinoma. Although no definite association of fractional allelic loss value to clinical prognosis of each case was found in osteosarcoma, tumors with 17p loss were more prone to the early onset of lung metastasis than tumors without 17p loss, indicating that allele loss on chromosome 17p can be a useful measure of prognosis.

Adolescent↗
PubMedDate not supplied

[Markers of bone formation in children with osteosarcoma].

UNLABELLED: Among biochemical markers, which reflect bone remodeling and can be measured in blood, there are formation markers such as serum bone alkaline phosphatase (BALP) and osteocalcin (OC). Formation markers are considered to be useful in diagnosis and anticancer treatment of many metastatic bone diseases, but the clinical value of these markers in primary osseous tumours such as osteosarcoma is not yet recognized. AIM: The aim of this study was the investigation of BALP activity and OC level in patients with osteosarcoma during clinical treatment. SUBJECTS AND METHODS: We studied 22 patients (aged 11-19 years) with osteosarcoma, at diagnosis, during preoperative and postoperative chemotherapy and at the end of treatment. The control group consisted of 30 healthy age-matched children. The activity of BALP and the level of OC were measured in serum using ELISA kits. RESULTS: Our results indicated that both tested parameters were lower during preoperative and postoperative chemotherapy (BALP, p<0.05; OC, p<0.01,p<0.001), in patients group than in controls. However we found higher value of BALP and OC also at diagnosis and during chemotherapy in same patients before occurrence of metastases. Moreover, we observed markedly higher activity of BALP (5:fold) and level of OC (2-fold) in patients with progression in comparison to the group with favourable prognosis, who responded to chemotherapy. CONCLUSIONS: Our studies suggest, that investigation of formation markers, especially BALP could be useful in monitoring of osteosarcoma therapy and may be a valuable indicator of the progression of this disease. Further studies with long-term observation of investigated patients are necessary.

Adolescent↗
PubMedDate not supplied

[Cytometric analysis of the relation between aneuploidy and expression of receptors for insulin growth factor I in child and adolescent osteosarcoma, after preliminary chemotherapy].

INTRODUCTION: Aneuploidy cell population is often seen as a marker of malignancy. The influence of growth factors on this cell population is of interest for oncologists, in the context of the clinical course of disease and the results of therapy. AIM: To investigate of reciprocal relations between aneuploidy parameters and expression of receptors of insulin-like growth factor I (IGF-IR) in osteosarcomas after preliminary chemotherapy. MATERIAL AND METHODS: Flow cytometric analysis was carried out in 20 children with osteosarcoma (aged 6 to 18 years) after preliminary chemotherapy. Biopsy material was taken during operation. RESULTS: It was shown, that higher aneuploid fraction and DNA index correlate with higher IGF-IR expression (significant difference p<O, 05). It may influence the sensitivity of osteosarcoma with higher aneuploidy fraction on the IGF-1, and in consequence may result in increasing proliferation. CONCLUSIONS: The suggestion concerning higher susceptibility of osteosarcoma's with higher aneuploidy on IGF-1 should be verified by longer clinical observation concerning survival rate in the two groups; the group with higher and the group with lower aneuploidy and IGF-IR expression.

Adolescent↗
PubMed2005

[Inducing specific antitumor effects on osteosarcoma by fused vaccine of rat dendritic cells].

BACKGROUND & OBJECTIVE: Dendritic cells (DCs) are the strongest antigen presenting cells (APCs). But immune therapy based on DCs for osteosarcoma has seldom been reported. This study was designed to investigate the immunologic potency and antitumor effects of fused vaccine of rat DCs on osteosarcoma. METHODS: Mononuclear cells in rat bone marrow were propagated in vitro under the condition of recombinant granulocytemacrophage colony-stimulating factor (rGM-CSF), recombinant interleukin-4 (rIL-4), and recombinant tumor necrosing factor-alpha (rTNF-alpha) to obtain DCs. DCs were purified by monoclonal antibody OX62 and magnetic beads, and confirmed by morphologic observation, phenotype determine, and functional experiments. Osteosarcoma cell line UMR-106 was fused with allogeneic or syngeneic DCs by electrofusion to produce the tumor vaccine. Each kind of tumor vaccine was injected subcutaneously into 10 rats to observe its specific antitumor effects. RESULTS: Survival rate of rats after injection of 1x10(7) UMR-106 cells was 70% in allogeneic tumor vaccine group, and 50% in syngeneic tumor vaccine group. The survival rats stood up to the second challenge of 1x10(7) UMR-106 cells 7 weeks after injection. After immunization of 2x10(6) UMR106-DCs, tumors in 60% of the rats bearing pre-established tumor cells diminished or vanished. CONCLUSION: Fused tumor vaccine of UMR-106 cells and allogeneic DCs might induce specific anti-tumor effects on osteosarcoma.

Animals↗
PubMed2005

[Construction of antisense c-myc recombinant adenovirus and its anti-tumor effects on osteosarcoma cell lines MG-63 and U2OS].

BACKGROUND & OBJECTIVE: c-myc, an oncogene, plays an important role in regulation of cell proliferation, and has been found to be amplified and overexpressed in osteosarcoma. Moreover, it can promote cell transformation, and induce metastasis. This study was to construct recombinant adenovirus encoding antisense c-myc, and to investigate its effects on osteosarcoma cell lines MG-63 (p53-deficient) and U2OS (with wild type p53). METHODS: Recombinant adenovirus Ad-As-c-myc encoding antisense c-myc was constructed by gene reconstruction technique, defined by polymerase chain reaction (PCR), and transfected into human osteosarcoma cell lines MG-63 and U2OS. Western blot, acridine orange staining, reverse transcription-PCR (RT-PCR), and flow cytometry (FCM) were used to detect expression of c-myc, proliferation, apoptosis, and cell cycle of MG-63 and U2OS cells. RESULTS: Ad-As-c-myc encoding antisense c-myc was obtained with the titer of 2x10(9) pfu/ml. Ad-As-c-myc significantly inhibited proliferation of both cell lines, while U2OS with wild type p53 was more susceptible to Ad-As-c-myc. Expression of c-myc mRNA was down-regulated in 2 cell lines 48 h after transfection of Ad-As-c-myc. Acridine orange staining and FCM analysis showed that Ad-As-c-myc induced apoptosis of both cell lines, cell cycle analysis showed obvious G(2)/M phase arrest in MG-63 cells,and G1 phase arrest in U2OS cells after transfection of Ad-As-c-myc. CONCLUSION: Ad-As-c-myc could induce apoptosis through both P53-dependent and P53-independent pathways, and inhibit proliferation of osteosarcoma cells.

Adenoviruses, Human↗
PubMed2005

[Therapeutic effects of RNA interference targeting HIF-1 alpha gene on human osteosarcoma].

OBJECTIVE: To investigate the inhibition effect of the small hairpin RNA (shRNA) targeting HIF-1alpha gene on the growth of osteosarcoma in vitro and in vivo. METHODS: The small hairpin RNA (shRNA) eukaryotic expression vector targeting HIF-1alpha gene, named pSilencer-HIF, was constructed and transfected into cultured human osteosarcoma cell of line SaOS-2 via liposome reagent. Then the osteosarcoma cells were cultured under chemical hypoxia conditions. The inhibition effects on HIF-1alpha gene were determined by semi-quantitative reverse transcription PCR and Western blot analysis. The in vitro cellular growth activities were assayed by MTT colorimetry. The cell apoptosis was studied by electron microscopy, TUNEL assay, and annexin V/PI double staining. Eighteen Balb/C mice were randomly divided into 3 equal groups to be inoculated with SaOS-2/shRNA, SaOS-2/neo (blank vector), or SaOS-2 subcutaneously respectively and then the appearance and size of tumors were observed. Four weeks later the mice were killed and the volumes of tumor were calculated so as to evaluate the therapeutic effects of shRNA. RESULTS: The successful construction of pSilencer-HIF plasmid was identified with sequencing. After the shRNA expression vector was transfected into the SaOS-2 cells, the expression of HIF-1alpha gene was inhibited significantly (by 90%). The cellular growth activities in the SaOS-2 cells transfected with pSilencer-HIF plasmid decreased obviously in hypoxia culture. After 72 hours of exposure to hypoxia, electron microscopy and TUNEL assay showed classic apoptosis characters in the SaOS-2 cells transfected with pSilencer-HIF plasmid with an apoptosis rate of 18.71% +/- 0.98%, significantly higher than those in the negative control group transfected with pSilencer-neo and in the nontransfected group (both P < 0.01). The growth speed and formation rate of xenograft tumor in pSilencer-HIF transfected mice slowed down significantly. A lot of necrotic tissues could be observed in the pSilencer-HIF transfected group by HE staining, however, there was no similar inhibitive effect in the control groups. CONCLUSION: shRNA targeting HIF-1alpha gene blocks the hypoxia transduction pathway efficiently and inhibits the growth of osteosarcoma cells.

Animals↗
PubMed2005

[Effect of silencing HIF-1alpha by RNA interference on expression of vascular endothelial growth factor in osteosarcoma cell line SaOS-2 under hypoxia].

BACKGROUND & OBJECTIVE: Hypoxia-inducible factor-1 alpha (HIF-1alpha) is a key regulator for hypoxia tolerance and angiogenesis of tumor. This study was to investigate the expression of HIF-1alpha and vascular endothelial growth factor (VEGF) in human osteosarcoma cell line SaOS-2 under hypoxia, to explore the effect of HIF-1alpha on hypoxia-activated angiogenesis regulation pathway in osteosarcoma. METHODS: CoCl2 was used as chemical hypoxia-inducing reagent to mimic tumor hypoxic microenvironment. mRNA and protein levels of HIF-1alpha and VEGF at different hypoxic culture phases were detected by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. Small hairpin RNAs (shRNAs) eukaryotic expression vector targeting HIF-1alpha was constructed, and transfected into SaOS-2 cells. Western blot was used to detect gene silencing effect on HIF-1alpha. RT-PCR and enzyme-linked immunosorbent assay (ELISA) were used to observe the change of VEGF gene expression after HIF-1alpha gene silence. RESULTS: Under hypoxia, mRNA level of HIF-1alpha kept stable, while its protein level increased obviouslyu both mRNA and protein levels of VEGF were up-regulated. The shRNAs plasmid targeting HIF-1alpha gene was constructed successfully, and down-regulated HIF-1alpha gene in SaOS-2 cells efficiently followed by VEGF gene down-regulation. CONCLUSIONS: Hypoxia can increase protein level of HIF-1alpha in osteosarcoma. HIF-1alpha up-regulates the gene expression of VEGF via transcription activation which promotes angiogenesis in osteosarcoma under hypoxic microenvironment.

Bone Neoplasms↗
PubMed2005

Construction of a human Fab phage display library from antibody repertoires of osteosarcoma patients.

Osteosarcoma is the commonest type of primary malignant bone tumor, frequently found in adolescents at sites of rapid bone growth. Despite current management protocols, up to half of the patients succumb to this disease. Moreover, there is no well-characterized molecular marker for diagnosis and prognosis. Since phage display methodology allows the selection of human antibody fragments with potential use in clinical applications, we applied this procedure to construct a recombinant Fab (antigen binding fragment) library from patients with osteosarcoma. We used peripheral blood lymphocyte total RNA from 11 osteosarcoma patients and cloned recombinant Fab representing the micro, gamma and kappa chain antibody repertoires of these individuals. The resulting library was cloned in the pComb3X vector and attained 1.45 x 10(8) different functional forms. BstO I fingerprinting and DNA sequencing analysis of randomly selected clones revealed the diversity of the library, demonstrating that Fab harbors Vkappa chains from subgroups I to V, biased towards the A27 fragment, as normally reported for the human repertoire. Analysis of the VH repertoire revealed that our library has a slight bias towards the VH4 family, instead of the usually reported VH3. This is the first description of a phage display library from osteosarcoma patients. We believe these human Fab fragments will provide a valuable tool for the study of this neoplasia and could also contribute to improvements in the diagnosis of this disease.

Adult↗
PubMed2006

Increased expression of membrane-type matrix metalloproteinase-1 is correlated with poor prognosis in patients with osteosarcoma.

Numerous studies have demonstrated a correlation of matrix metalloproteinase (MMP) overexpression with the prognosis of various kinds of cancer. The current study investigated whether the expression of MMPs is correlated with the prognosis of osteosarcoma. Expression levels of MMP-2, -9, MT1-MMP and TIMP-2 were examined immunohistochemically in samples from 47 patients with osteosarcoma. Correlation of the positivity of staining with prognosis was analyzed with the Kaplan-Meier method, and statistically analyzed with log-rank test. Co-localization of MMP-2, MT1-MMP and TIMP-2 was determined by double staining with fluorescence-conjugated antibodies. Activities of gelatinases in representative tissues were examined with gelatin zymography. MMP-2 was expressed strongly in 60% of cases (28/47), and MMP-9, MT1- MMP and TIMP-2 was strongly positive in 61% (29/47), 45% (21/47), and 91% (43/47), respectively. Increased MT1-MMP expression was associated significantly with poor prognosis in overall survival (P=0.0480). In cases of overexpression for both MMP-2 and MT1-MMP, there was a tendency for poor prognosis (P=0.0969). In 36 cases who underwent neoadjuvant chemotherapy, wide resection of the tumors and post-operative adjuvant chemotherapy, increased expression of MT1-MMP resulted in a significant negative prognostic factor for disease-free survival (P=0.0143). Also, co-overexpression of MT1-MMP and MMP-2 showed a tendency to correlate to the reduced disease-free survival (P=0.0502). Increased gelatinase activity was observed in tissues of co-overexpression of MT1-MMP and MMP-2. The results of this study demonstrate the correlation of MT1-MMP expression and the oncological outcome of osteosarcoma patients, suggesting the prognostic significance of these proteins in osteosarcoma patients.

Adolescent↗
PubMed2006

High energy shock waves enhance the cytotoxic effect of doxorubicin and methotrexate to human osteosarcoma cell lines.

Despite recent advances, the prognosis of relapsed osteosarcoma patients remains very poor. Application of high energy shock waves may change the tumour cell growth and increase the cytotoxic effect of in vivo and in vitro chemotherapeutic agents. We studied the effect of their association with doxorubicin or methotrexate on three in vitro osteosarcoma cell lines. The effect of these combinations on SJSA-1, MG-63 and HOS human osteosarcoma cell lines were evaluated through incubation with doxorubicin or methotrexate and high energy shock wave treatment with 1000 shots at 0.22 mJ/mm(2) and an evaluation of the cell number, cell proliferation and apoptosis at days 1, 3 and 6 from the start of treatment. The combination of high energy shock waves and doxorubicin induced a statistically significant advantage in terms of a decrease in cell number on the SJSA-1 and HOS cell lines, a decrease of cell proliferation on all three cell lines and an increase of apoptosis only on the SJSA-1 cell line. The combination of high energy shock waves with methotrexate induced a decrease of the cell number only in the SJSA-1 and in the HOS cell lines, of the cell proliferation in the SJSA-1 and in the MG-63 cell lines, and an increase of apoptosis only on the SJSA-1 cell line. In conclusion, these experiments show an interesting effect of high energy shock waves on osteosarcoma cell lines, which could lead to future studies of the in vivo effects of high energy shock waves in the murine model as well.

Antineoplastic Agents↗
PubMedDate not supplied

Peritoneal metastasis in osteosarcoma: report of one case.

We describe a rare case of peritoneal metastasis in osteosarcoma. A 14-year-old boy was diagnosed with osteosarcoma of the femur. Although initial treatment with surgical resection and chemotherapy was successful, a large inoperable pulmonary metastasis was detected 27 months after diagnosis of the primary tumor. At 38 months, whilst still receiving salvage chemotherapy, malignant ascites with peritoneal metastasis was detected. The patient died two months later from disease progression. This is probably the 6th case and youngest patient with peritoneal metastasis of osteosarcoma reported in the literature. For early diagnosis, patients with a history of osteosarcoma having persistent abdominal symptoms or signs should be offered a CT scan of the abdomen, and examination of the ascitic fluid when present. With advances in treatments, unusual sites of metastasis may become more prevalent.

Adolescent↗
PubMed2006

Osteosarcoma among children aged 5 years or younger: the St. Jude Children's Research Hospital experience.

Osteosarcoma primarily affects adolescents. The authors reviewed the records of eight patients aged 5 years or younger (of 470 patients with osteosarcoma) treated at their institution. Tumors (seven of high grade and one of low grade) arose mostly in the appendicular skeleton; one patient had metastases. One patient with low-grade osteosarcoma survived after surgery alone. Two with active disease died of chemotherapy toxicity. The remaining five (three received chemotherapy) underwent surgery and are long-term survivors. Two who underwent hemipelvectomy or hip disarticulation would likely have undergone limb-sparing surgery today. These findings and a review of the similar cases in the literature suggest that osteosarcoma's clinical characteristics are similar among young children and older children.

Age Factors↗
PubMed2006

Kissing pleural metastases from metastatic osteosarcoma of the lung.

Two patients with osteosarcoma lung metastases of which migrated to the parietal pleura due to contact are reported. The first patient was a 16-year-old male who had a pleural metastasis in the diaphragm within an area in contact with a single lung metastasis. Both of the tumors were resected, followed by systemic chemotherapy. Nine months after the resection of the first metastases, two other lung metastases were found which were resected after chemotherapy. The patient is alive without recurrence 84 months after the first resection of the metastases. The second patient was an 11-year-old female with a pleural metastasis of osteosarcoma which was within an area in contact with a single lung metastasis, which had been resected 4 months before. We concluded (1) that a lung metastasis of osteosarcoma occasionally metastasizes to the pleura due to contact; and (2) that because this kissing metastases of osteosarcoma could be cured by a complete resection, the intrathoracic cavity should be thoroughly observed.

Adolescent↗