Immunotherapy with autologous dendritic cells and tumor-specific synthetic peptides for synovial sarcoma

Synovial sarcoma in an 11-year-old Japanese girl relapsed 5 months after autologous stem cell transplantation. Autologous dendritic cells (DCs) were generated from her peripheral blood mononuclear cells using granulocyte/macrophage colony-stimulating factor and IL-4. Dendritic cells were pulsed with synthetic peptides containing a junctional region of SYT-SSX2 fusion protein generated by t(X;18) and were administered once per week. No side effects were observed. Growth of metastatic nodules in the lung was temporally suppressed. The delayed-type hypersensitivity responses in skin were enhanced to tumor lysate but not to peripheral blood mononuclear cell lysate. The CD3+ cells cultured with pulsed DCs lysed tumor cells in vitro. Immunotherapy using DCs and tumor-specific peptides may be a safe approach in the treatment of childhood cancer.     

Establishment of a prostatic small-cell carcinoma cell line (SO-MI)

BACKGROUND: Prostatic small-cell carcinoma is an extremely rare, highly aggressive disease. We established a cell line from this tumor. MATERIALS AND METHODS: Tumor tissue obtained from a 24-year-old Japanese man was used to establish the cell line. Cultured cells and tumors transplanted into nude mice were characterized by histologic, immunohistologic, immunocytologic, and molecular biologic methods. RESULTS: An immortal culture cell line (SO-MI) was successfully established. SO-MI cells adhered weakly to plastic surfaces in vitro, showing a 52- to 72-hr doubling time. SO-MI cells were heterotopically and orthotopically transplantable in nude mice. The cells were immunoreactive for NSE, chromogranin A, and NCAM, but not for ACTH, calcitonin, serotonin, gastrin, insulin, glucagons, LCA, EMA, PAP, PSA, androgen receptor, and p53. SO-MI cells secreted NSE in vitro and in vivo. SO-MI cells at passage 30 contained 50-59 chromosomes with a modal number of 55. PCR suggested that the p53 gene was deleted in SO-MI cells. RT-PCR detected no mRNA encoding androgen receptor in these cells. CONCLUSIONS: SO-MI cells retain the neuroendocrine nature of the original tumor, and should be useful in studying possible etiologies and new treatments.     

A case of dissociative stupor with decorticated posture after neck clipping of brain aneurysm

We experienced a case of dissociative stupor with decorticated posture in a 71-year-old woman after neck clipping of the brain aneurysm. Decorticated posture is observed with severe midbrain disorder caused by brain herniation. In this case, therefore, severe brain stem damage was suspected, although light reflex was observed and respiration was stable. In addition, in this case, the aneurysm was located at the junction of the internal carotid artery and the posterior communicating artery. Therefore, surgical damage to midbrain was not likely to have happened. Postoperative computed tomography showed no abnormality in this region. Two days later, her symptom disappeared, and she could clearly recollect memory of these two days just after surgery. However, she could not follow directions because of a sense of fear. Thus her symptom might be based on a kind of mental disorder. Patients with conversion disorder react abnormally to stimulus or stress. Stupor was diagnosed as due to defect of reaction to stimulus of sound, light and touch. She was diagnosed as dissociative stupor of the conversion disorder type. In this case, decorticated posture was caused by mental disorder. We have to pay attention not only to brain tissue damage but also to psychological damage of patients.     

Iressa (gefitinib)

Gefitinib is an epidermal growth factor receptor (EGFR) inhibitor that is reported to be well tolerated and active in patients with chemotherapy-resistant non small cell lung cancer. On the other hand, gefitinib was also reported to produce a severe adverse event, interstitial lung disease, in less than 2% of treated patients. Given these circumstances, it is important to evaluate this drug and to establish its use clinically. We do not have sufficient data to evaluate gefitinib at this time. Phase III study of second/third line or maintenance therapy using gefitinib is required for such an evaluation. The development of individualized therapy with gefitinib might be also be required.     

Endoscopic local ablation therapy (ELAT) for hepatocellular carcinoma--inventive approaches to achieve radical treatment and to expand the indication of ELAT

We introduce some inventive approaches in endoscopic local ablation therapy (ELAT) for patients with hepatocellular carcinoma (HCC). ELAT is applied in cases of HCC when the tumor is smaller than 3 cm on the surface of the liver (smaller than 4 cm with extrahepatic growth), and tumor numbers < or = 3. Appropriate use of the laparoscopic, thoracoscopic and hand-assisted approaches, suitable preceding embolizations with the angiographic technique, a combination of ablation therapy, and the use of CO2-angio US, DIMON puncture system and cluster needle are important. If necessary, additional surgeries such as endoscopic hepatectomy, laparoscopic cholecystectomy or laparoscopic devascularization must be performed together. As a result, it will be possible to expand the indication of ELAT safely and radically.     

In vivo antitumor activity of pegylated zinc protoporphyrin: targeted inhibition of heme oxygenase in solid tumor

High expression of the inducible isoform of heme oxygenase (HO-1) is now well known in solid tumors in humans and experimental animal models. We reported previously that HO-1 may be involved in tumor growth (Tanaka et al., Br. J. Cancer, 88: 902-909, 2003), in that inhibition of HO activity in tumors by using zinc protoporphyrin (ZnPP) significantly reduced tumor growth in a rat model. We demonstrate here that poly(ethylene glycol)-conjugated ZnPP (PEG-ZnPP), a water-soluble derivative of ZnPP, exhibited potent HO inhibitory activity and had an antitumor effect in vivo. In vitro studies with cultured SW480 cells, which express HO-1, showed that PEG-ZnPP induced oxidative stress, and consequently apoptotic death, of these cells. Pharmacokinetic analysis revealed that PEG-ZnPP-administered i.v. had a circulation time in blood that was 40 times longer than that for nonpegylated ZnPP. More important, PEG-ZnPP preferentially accumulated in solid tumor tissue in a murine model. In vivo treatment with PEG-ZnPP (equivalent to 1.5 or 5 mg of ZnPP/kg, i.v., injected daily for 6 days) remarkably suppressed the growth of Sarcoma 180 tumors implanted in the dorsal skin of ddY mice without any apparent side effects. In addition, this PEG-ZnPP treatment produced tumor-selective suppression of HO activity as well as induction of apoptosis. The major reason for tumor-selective targeting of PEG-ZnPP is attributed to the enhanced permeability and retention effect that is observed commonly in solid tumors for biocompatible macromolecular drugs. These findings suggest that tumor-targeted inhibition of HO activity could be achieved by using PEG-ZnPP, which induces apoptosis in solid tumors, probably through increased oxidative stress.     

Trial of intraventricular ribavirin therapy for subacute sclerosing panencephalitis in Japan

Ten patients with SSPE were surveyed during the last 4 years from the viewpoint of clinical safety for use of ribavirin therapy. Although effectiveness varied among cases, they were all treated safely with intraventricular ribavirin. This study suggests that treatment is safe and well-tolerated.     

Bumetanide-induced enlargement of the intercellular space in the stria vascularis critically depends on Na+ transport

The intercellular space in the stria vascularis (intrastrial space) is a closed space and isolated from both the endolymph and the perilymph in normal tissue. Loop diuretics such as bumetanide and furosemide cause an acute enlargement of the intrastrial space in association with a decline in the endocochlear potential. It is known that bumetanide inhibits the Na+-K+-2Cl- cotransporter, which is expressed abundantly in the basolateral membrane of marginal cells. We studied ionic mechanisms underlying the bumetanide-induced enlargement of the intrastrial space using perilymphatic perfusion in guinea pigs. Perilymphatic perfusion with artificial perilymph containing 100 microM bumetanide caused marked enlargement of the intrastrial space, as reported previously. Removal of K+ from the perilymph did not affect the bumetanide-induced enlargement, whereas removal of Na+ from the perilymph inhibited it almost completely. Perilymph containing 1 mM amiloride also inhibited the enlargement of the intrastrial space almost completely. These results indicate that perilymphatic Na+, but not K+, and amiloride-sensitive pathways are essential to the bumetanide-induced enlargement of the intrastrial space. Two possible pathways could yield these results. Na+ in the perilymph could enter the endolymph via Reissner's membrane or the basilar membrane; Na+ in the endolymph would then be taken up by marginal cells via the apical membrane and secreted into the intrastrial space by Na+-K+-ATPase in the basolateral membrane of them. Another, less likely possibility is that Na+ in the perilymph is transported into basal cells or fibrocytes in the spiral ligament, then into intermediate cells via gap junctions, and finally secreted into the intrastrial space via Na+-K+-ATPase of intermediate cells.