Biomedical subjects

S Hashiguchi

Publications and source records attributed to S Hashiguchi.

113 records · Page 7Linked to original sources

PubMedDate not supplied

Case report of secondary chondrosarcoma showing spontaneous regression after frequent recurrences.

We report a case of secondary chondrosarcoma arising in the ilium showing spontaneous regression after frequent local tumor recurrences followed by multiple surgeries of marginal or intralesional excision. The patient was a 16-year-old boy who had been diagnosed as having multiple exostosis from 9 years of age. He experienced an increasing abdominal tumor mass that formed a huge tumor. Although marginal resection of the tumor was attempted, intraperitoneal dissemination was caused by rupture of the tumor capsule and the peritoneum, as a result of severe tumor adhesion to the peritoneum. During the 5 years after the initial operation, local recurrences occurred seven times in various areas of the intra- or retro-peritoneum and marginal or intralesional excision was performed every time for a total of 14 tumors. However, since the seventh operation, the patient has had no evidence of recurrence or metastasis of the disease for more than 10 years. Therefore, we considered that the cancer might have spontaneously regressed.

Adolescent↗

PubMedDate not supplied

Extraabdominal desmoid tumor with dissemination detected by thallium-201 scintigraphy.

Extraabdominal desmoid tumor is a locally aggressive tumor despite being histologically benign. To avoid local recurrence, it is important to preoperatively detect the exact localization and extension of the infiltrating or disseminating lesion in this tumor. We report a case of recurrent extraabdominal desmoid tumor, which arose in the posterior thigh region, detected with Tl-201 (Tl) scintigraphy. In this case, Tl accumulated in the small disseminating lesion and to the recurrent tumor. This lesion was not identified by palpation because of its small size, deep localization and absence of symptoms, although MR imaging, which was performed after the Tl scintigraphy, clearly showed the lesion. After tumor resection, Tl did not accumulate in any region. These results suggest that Tl scintigraphy may be useful, not only for the diagnosis of extraabdominal desmoid tumor, but also for the detection of the exact localization or extension of small infiltrating or disseminating lesions before treatment.

Female↗

PubMedDate not supplied

Assessment of chemosensitivity in patients with malignant bone and soft tissue tumors using thallium-201 scintigraphy and doxorubicin binding assay.

This study was performed to compare the accumulation of thallium (Tl)-201 which is correlated with malignancy and the doxorubicin binding ability, which is correlated with chemosensitivity, in nine patients who received preoperative chemotherapy with doxorubicin and cisplatin. Tl-201 scintigraphy was performed at 15 minutes (early image) and 3 hours (delayed image) after injection of 111 MBq of Tl-201. The change of degree of the radionuclide uptake between the early and delayed images was evaluated before and after preoperative chemotherapy. The doxorubicin binding ability (%DB) to nuclear DNA in living tumor cells isolated from biopsy materials was assessed by doxorubicin binding assay. The histologic response to preoperative chemotherapy was evaluated by the percentage of tumor necrosis. Before preoperative chemotherapy no changes of Tl-201 uptake between the early and delayed images was detected in any tumors. Five patients, who had no change of Tl-201 uptake after preoperative chemotherapy, showed a poor histologic response and had a %DB ranging from 10% to 70% (mean: 36.0%). The other four patients, who had a %DB greater than 90%, showed a good histologic response. All of these four patients had decreased Tl-201 uptake after preoperative chemotherapy. This study demonstrated that doxorubicin binding assay and midcourse Tl-201 scintigraphy are useful methods to assess the response to chemotherapy early in malignant bone and soft tissue tumors.

Adolescent↗

PubMedDate not supplied

Drug resistance modification using pulsing electromagnetic field stimulation for multidrug resistant mouse osteosarcoma cell line.

Multidrug resistance (MDR) is one of the major problems in osteosarcoma chemotherapy. Therefore, methods of overcoming MDR are urgently needed. In this study, we investigated the effects of pulsing electromagnetic field stimulation (PEMFs) on a MDR murine osteosarcoma cell line which strongly expresses P-glycoprotein (P-gp). To assess the reversal effects of PEMFs on doxorubicin (DOX) resistance, MTT assay was applied. Viable cells were assessed by the trypan blue exclusion test. Fluorescence intensity of DOX binding to nuclear DNA of each cell was measured using a cytofluorometer. Changes in P-gp expression in each cell were detected by the indirect immunofluorescence method using an antibody to Pgp. PEMFs increased DOX binding ability to nuclear DNA and inhibited cell growth, although it had no significant effect on P-gp expression. These findings indicated that PEMFs reversed the DOX resistance of the MOS/ADR1 cells by inhibiting P-gp function. The results suggested that PEMFs may be useful as a local treatment for MDR osteosarcoma.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMedDate not supplied

Avoidance of doxorubicin resistance in osteosarcoma cells using a new quinoline derivative, MS-209.

P-glycoprotein (Pgp), a membrane drug efflux pump, is thought to be responsible for the observed drug resistance in osteosarcoma. We have recently developed Pgp-positive, multidrug resistant (MDR) murine osteosarcoma cell lines, which may be suitable models for the study of drug resistance in osteosarcoma. In this study, we investigated the effect of a newly synthesized quinoline compound, MS-209, on the reversal of doxorubicin (DOX) resistance in these cell lines. Three different types of resistance modifying agents (RMAs) as well as MS-209 were studied. These included the calcium channel blocker verapamil, and the immunosuppressive agents cyclosporin A and FK506. The reversal effects of the RMAs on DOX resistance were assessed by the MTT assay. In the absence of RMAs, the MDR osteosarcoma cells were 20-fold more resistant to DOX than the parental cells. When MS-209 was added at a final concentration of 0.1 to 3 microM to the MDR cells, 3-to 74-fold sensitization was observed. A complete reversal (37-fold sensitization) of the resistance was obtained at 1 microM MS-209. This concentration of MS-209 was 3-, 8- and 28-fold more effective than the same concentration of FK506, verapamil and cyclosporin A, respectively. These results indicate that MS-209 may be a more effective RMA, and that DOX resistance in osteosarcoma cells could be reversed by comparatively low doses of MS-209.

Antineoplastic Agents↗