Expression of MAGE genes in renal cell carcinoma

We investigated the expression of MAGE genes in 10 renal cell carcinoma (RCC) cell lines, 50 RCC tumor samples and 5 normal kidney samples using reverse transcription-polymerase chain reaction (RT-PCR). MAGE-1, -2, -3 and -4 genes were expressed in 4, 1, 10 and 3 of 10 RCC cell lines, respectively, and 11, 8, 38 and 15 of 50 RCC samples. In contrast, there was no expression of MAGE genes detected in any of the normal kidneys. The incidence of the expression of plural MAGE genes in high stage RCC was significantly higher than that in low stage RCC. An analysis based on clinicopathological factors revealed that MAGE-4 gene was more frequently expressed in clear cell subtype than in granular cell subtype RCCs. Our results suggest that owing to the high incidence of MAGE gene expression in RCC, a large proportion of patients could be suitable candidates for novel immune therapies involving tumor-specific antigens encoded by MAGE genes.

Enhancement of chemosensitivity in human bladder cancer cells by adenoviral-mediated p53 gene transfer

BACKGROUND

Drug resistance is a major problem in tumor chemotherapy, and recent studies have suggested that the differential sensitivity of cancer cells to chemotherapy is associated with different susceptibilities to undergoing apoptosis. The aim of this study was to evaluate the effects of introduction of wild-type p53 or p21WAF1/CIP1 (p21) on chemosensitivity of bladder cancer cells.

MATERIALS AND METHODS

The human bladder cancer cell line HT1376, which contains mutant p53 and p21 genes, was used in this study. The effects of adenoviral-mediated p53 or p21 gene transfer on sensitivity of HT1376 cells to cisplatin were analyzed both in vitro and in vivo.

RESULTS

The introduction of wild-type p53 gene into HT1376 markedly enhanced the sensitivity to cisplatin in vitro. Direct injection of the p53-adenoviral vector into subcutaneous HT1376 tumors established in nude mice, followed by intraperitoneally administration of cisplatin, induced massive apoptotic destruction of the tumors. In contrast, the sensitivity of HT1376 to cisplatin was not increased by the introduction of the p21 gene either in vitro or in vivo.

CONCLUSIONS

These findings suggest that the combined regimen of adenoviral-mediated p53 gene transfer and cisplatin may become an efficient and powerful tool for treatment of bladder cancer.

Long-term follow-up study of penile cancer

BACKGROUND

We reviewed the outcomes for patients with penile cancer to determine factors predictive of their survival.

METHODS

Between 1966 and 1996, 59 patients with penile cancer were treated at Kobe University Hospital. The median follow-up period was 109 months (range, 4 to 240 months). The prognostic factors were determined by multivariate analysis. Disease progression rates, according to stage and the type of surgery, were studied.

RESULTS

The 5- and 10-year, cause-specific survival rates were 75.9% and 73.8%, respectively. Lymph node involvement, tumor stage, and tumor differentiation were the independent risk factors identified by multivariate analysis. Among the patients at stage 1 and 2, none of the 29 patients treated with early lymphadenectomy showed recurrence in the inguinal region, while 4 (27%) of 15 patients without lymphadenectomy showed such recurrence.

CONCLUSION

Our results suggest that tumor stage, lymph node involvement, and tumor differentiation are significant prognostic factors for survival, and that early inguinal lymphadenectomy would improve the prognosis of patients with stage 1 or 2 penile cancer.

Expression patterns of CD44 adhesion molecule in testicular germ cell tumors and normal testes

Despite recent extensive immunohistochemical studies, the expression patterns of CD44 in testicular germ cell tumors are still controversial. In the present study, we investigated the CD44 gene expression in 40 specimens including 18 seminomas, 16 nonseminomatous germ cell tumors (NSGCT), and 6 normal testes by reverse transcriptase-polymerase chain reaction and Western blotting. Reverse transcriptase-polymerase chain reaction analysis revealed that the standard CD44 isoform (CD44s) was expressed in all of the specimens, whereas the variant CD44 isoforms were highly expressed in NSGCTs but barely detectable in seminomas and normal testes. In addition, we confirmed by direct DNA sequence analysis that the predominantly expressed variant isoform in NSGCTs was CD44v8-10. In germ cell tumors, these results were paralleled in Western blot analysis; that is, CD44s protein was expressed in all of the tumor specimens, whereas high molecular weight variant isoforms were expressed only in NSGCTs. However, at the protein level, no detectable CD44 was expressed in normal testes. These findings show that the combined assessment of CD44 expression patterns at both the RNA and protein levels enables us to distinguish among seminoma, NSGCT, and normal testis specimens; hence, it could serve as a useful practical adjunct to conventional diagnostic methods for testicular germ cell tumors.

Influence of cytokines and growth factors on matrix metalloproteinase-2 production and invasion of human renal cancer

This study evaluated the influence of cytokines and growth factors on the production of matrix metalloproteinase-2 (MMP-2, 72-kDa type IV collagenase, gelatinase A) and invasion of the human renal cell carcinoma (HRCC) cell line KG-2. The cells were treated with cytokines and growth factors, and the gelatiolytic activity and in vitro invasion were examined. Basic fibroblast growth factor (bFGF) stimulated MMP-2 production by KG-2 cells to 2.0-, 4.84- and 4.53-fold that of the untreated group at 0.1, 1.0 and 10 ng/ml, respectively. Transforming growth factor-beta1 (TGF-beta1) at very low concentrations of 10 pg/ml and 100 pg/ml stimulated enzyme production in KG-2 cells by 1.74- and 2.83-fold, respectively. In contrast, interferon-gamma (IFN-gamma) decreased MMP-2 production by KG-2 cells at 10 and 100 U/ml to 69% and 41% of the level in the untreated group, respectively. At those concentrations, IFN-gamma did not cause cytostasis in KG-2 cells. Moreover, bFGF and TGF-beta1 (low concentrations) stimulated in vitro invasion of KG-2 cells, but IFN-gamma decreased the invasive activity, which was well correlated with the levels of MMP-2. However, the expression of MMP-2 mRNA of KG-2 cells treated with 10 ng/ml bFGF, 100 pg/ml TGF-beta1 and 100 U/ml IFN-gamma was shown to be 3.8-, 3.4- and 0.7-fold, respectively, those in untreated groups. Thus the production of MMP-2 in HRCC was influenced by cytokines and growth factors, and MMP-2 plays an important role in the invasion and metastasis of certain types of HRCC.

Multifocal renal cell carcinoma in Japanese patients with tumors with maximal diameters of 50 mm. or less

PURPOSE

We determined the risk of local recurrence in 64 Japanese patients a median of 69 years old with renal cell carcinoma who were possible candidates for nephron sparing surgery and who underwent radical nephrectomy.

MATERIALS AND METHODS

A total of 64 kidneys in which tumors 50 mm. or less were resected were prospectively examined pathologically in 3 mm. sections. The incidence of satellite tumors and the relationship between the pathological findings of the primary and satellite tumors were evaluated.

RESULTS

Satellite tumors were identified in 10 of the 64 kidneys (15.6%), a rate similar to that reported in the United States. The correlation of histological findings between primary and satellite tumors was 70% for tumor grade. Satellite tumor grade was less than that of the primary lesion in 3 cases. In 60% of the specimens with multifocal renal cancer satellite tumors were within 10 mm. of the margin of the primary tumor. At this distance, if partial nephrectomy had been performed, the satellite lesions would have been missed in 4 of these 10 patients (40%). Of the 10 kidneys with satellite renal tumors 8 (80%) had vascular invasion of the primary tumor. Multiple logistic regression analysis demonstrated that vascular invasion was a significant predictor of multifocality of renal cell carcinoma.

CONCLUSIONS

Our results suggest that vascular invasion is a risk factor for multifocality in Japanese patients with renal cell carcinoma. Therefore, careful and long-term followup is necessary in patients with renal cell carcinoma who have undergone nephron sparing surgery, especially those with vascular invasion of the primary tumor.

Serum matrix metalloproteinase-2 and its density in men with prostate cancer as a new predictor of disease extension

We examined whether the serum matrix metalloproteinase-2 (MMP-2) level and MMP-2 density could be predictors of the development and extension of prostate cancer. Serum samples were collected before any clinical treatment from 98 patients with prostate cancer and from 76 patients with benign prostatic hyperplasia (BPH). Control sera were obtained from 70 healthy men. The serum level of MMP-2 was determined by 1-step enzyme immunoassay. A newly defined MMP-2 density parameter was determined by dividing the serum level of MMP-2 by the prostate volume, which was measured by ultrasonography. The mean serum level of MMP-2 in prostate cancer patients was significantly higher than in the control and BPH groups. Furthermore, the serum MMP-2 levels in prostate cancer patients with metastasis were highly elevated compared with those without metastases. The MMP-2 density in pathologically organ-confined prostate cancer was significantly higher than that in BPH. There was a statistically significant difference in the MMP-2 density between pT2N0M0 and pT1N0M0 prostate cancers. Moreover, the serum MMP-2 level correlated well with the clinical course of prostate cancer with bone metastasis. Our results suggest that MMP-2 plays an important role in the development and extension of prostate cancer and that the serum level of MMP-2 and the MMP-2 density indicate prostate cancer extension and are, therefore, useful for the followup of prostate cancer patients.

Clinical study of renal cell carcinoma with brain metastasis

BACKGROUND

The clinical outcome of patients with renal cell carcinoma with brain metastasis was analyzed.

METHODS

Nine patients (median age, 60 years) with primary renal cell carcinoma and distant metastasis, including brain metastasis, were treated. The median time to the development of brain metastasis was 15 months after the initial visit. Patients with poor performance status or progressive disease were treated with interferon or conservative therapy alone. Patients with good performance status and other well-controlled metastatic foci were treated either with radiotherapy, or by tumorectomy of brain metastasis, or both. The median follow-up was 26 months after the initial visit.

RESULTS

The 1-year, cause-specific survival rate was 17%. Of the 5 patients treated with alpha-interferon alone, all died of disease after the treatments, without improvement of performance status, 1 to 4 months after the diagnosis of brain metastasis. Two of 4 patients who underwent radiotherapy were treated with a combination of gamma-knife and tumorectomy of brain metastasis. They remained alive 10 and 22 months after diagnosis of brain metastasis. The 2 patients who underwent the combination treatment of gamma-knife and tumorectomy showed improvement of their performance status after these treatments for brain metastasis.

CONCLUSION

Brain metastasis is an unfavorable prognostic factor in renal cell carcinoma. Although a larger number of patients would be necessary to demonstrate the definitive effects of gamma-knife treatment, our results suggest that the combination of gamma-knife and tumorectomy of brain metastases may be recommended for selected patients with good performance status and other well-controlled metastatic foci.

Preliminary report of a modified continent appendix stoma in a sigmoid urinary reservoir pouch

BACKGROUND

The application of an appendix stoma in a Mainz urinary reservoir pouch is an established procedure and assures good continence. We modified this method for use with a sigmoid pouch.

METHODS

In each of 3 men with bladder carcinoma, an appendix with a blood supply was prepared and anastomosed to the detubularized sigmoid pouch with a 3-cm submucosal tunnel.

RESULTS

In all 3 patients, this procedure was performed successfully, and the pouch was completely continent. Self-catheterization could be performed without difficulty by 2 patients, and with slight resistance in the remaining patient. The patients are satisfied with their quality of life.

CONCLUSIONS

We conclude, based on our findings and these preliminary observations, that this procedure is a potentially good alternative for the placement of continent stoma in continent urinary reservoir surgery.

Serum matrix metalloproteinase-2 and its density in men with prostate cancer as a new predictor of disease extension

We examined whether the serum matrix metalloproteinase-2 (MMP-2) level and MMP-2 density could be predictors of the development and extension of prostate cancer. Serum samples were collected before any clinical treatment from 98 patients with prostate cancer and from 76 patients with benign prostatic hyperplasia (BPH). Control sera were obtained from 70 healthy men. The serum level of MMP-2 was determined by 1-step enzyme immunoassay. A newly defined MMP-2 density parameter was determined by dividing the serum level of MMP-2 by the prostate volume, which was measured by ultrasonography. The mean serum level of MMP-2 in prostate cancer patients was significantly higher than in the control and BPH groups. Furthermore, the serum MMP-2 levels in prostate cancer patients with metastasis were highly elevated compared with those without metastases. The MMP-2 density in pathologically organ-confined prostate cancer was significantly higher than that in BPH. There was a statistically significant difference in the MMP-2 density between pT2N0M0 and pT1N0M0 prostate cancers. Moreover, the serum MMP-2 level correlated well with the clinical course of prostate cancer with bone metastasis. Our results suggest that MMP-2 plays an important role in the development and extension of prostate cancer and that the serum level of MMP-2 and the MMP-2 density indicate prostate cancer extension and are, therefore, useful for the followup of prostate cancer patients.

Overexpression of Bcl-2 in bladder cancer cells inhibits apoptosis induced by cisplatin and adenoviral-mediated p53 gene transfer

To investigate the effects of the expression of Bcl-2 protein in bladder cancer on the apoptosis induced by cisplatin or adenoviral-mediated p53 gene (Ad5CMV-p53) transfer, we transfected the bcl-2 gene into KoTCC-1, a human bladder cancer cell line that does not express the Bcl-2 protein. The Bcl-2-transfected KoTCC-1 (KoTCC-1/B) exhibited significantly higher resistance to both cisplatin and Ad5CMV-p53 transfer than did either the parental KoTCC-1 (KoTCC-1/P) or the vector-only transfected cell line (KoTCC-1/C). The flow cytometric analysis of the propidium iodide-stained nuclei and DNA fragmentation analysis after cisplatin or Ad5CMV-p53 treatment revealed DNA degradation in both KoTCC-1/P and KoTCC-1/C, whereas KoTCC1/B showed a marked inhibition of DNA degradation. Following the treatment with cisplatin or Ad5CMV-p53, the accumulation of p53 protein was highly detectable for a long period in KoTCC-1/B compared to that in KoTTC-1/P and KoTCC-1/C. Furthermore, the cisplatin and Ad5CMV-p53 treatments each reduced the volume of the subcutaneous tumors established in nude mice formed by KoTCC-1/P or KoTCC-1/C; in contrast, their reductive effects on the tumors formed by KoTCC-1/B were significantly suppressed. The intraperitoneal tumor cell implantation model revealed that the prognoses of mice injected with KoTCC-1/B were significantly inferior to those of the mice injected with either KoTCC-1/P or KoTCC-1/C after treatment with cisplatin or Ad5CMV-p53. These findings suggest that the expression of Bcl-2 in bladder cancer cells interferes with the therapeutic effects of cisplatin and Ad5CMV-p53 through the inhibition of the apoptotic pathway.

p53 modulation of Fas/Apo-1 mediated apoptosis in a human renal cell carcinoma cell line

The mutant p53 gene was transfected into ACHN, a wild-type p53-containing human renal cell carcinoma (RCC) cell line. The colony forming efficiency in soft agar in the mutant-type p53-transfected cell line (ACHN/MP) was significantly higher than that in the vector-only transfected control cell line (ACHN/C). The anti-Fas monoclonal antibody (CH11) induced apoptosis in the ACHN/C cells in a dose-dependent manner, whereas the effect of CH11 on the ACHN/ MP cells was markedly suppressed. In addition, the cytotoxic effect of CH11 on the ACHN/MP cells was augmented by the pretreatment with interferon- , but the corresponding effect on ACHN/C cells was not. These findings suggest that Fas-mediated therapy could be a novel approach to RCC, if interferon- treatment is added according to the p53 gene status.

Expression of basic fibroblast growth factor is associated with resistance to cisplatin in a human bladder cancer cell line

To clarify the role of basic fibroblast growth factor (FGF-2) in the drug resistance of bladder cancer, we transfected the FGF-2 gene into HT1376, an FGF-2 negative human bladder cancer cell line. The FGF-2-transfected cell lines exhibited three- to four-fold higher resistant potential to cisplatin than the vector-only transfected control cell lines in vitro. When cisplatin was injected intraperitoneally after s.c. implantation of HT1376 sublines into nude mice, FGF-2 transfectants formed tumors about twice as large as did controls. In contrast, there was no significant difference in either cell proliferation in vitro or tumor growth in vivo among these cell lines without cisplatin treatment. Furthermore, DNA degradation following cisplatin treatment was markedly suppressed in FGF-2 transfectants compared to control cells. These results suggest that the expression of the FGF-2 gene plays an important role in the acquisition of the cisplatin-resistant phenotype of bladder cancer, probably through the protection against cisplatin-induced apoptosis.

Construction and voiding functions of three types of orthotopic neobladders using colonic segments: the Kobe University experience

BACKGROUND

At Kobe University Hospital we have created orthotopic neobladders since 1988 by using several colonic segments. Various types of neobladders were compared and a detailed description of these procedures and the voiding function outcome is presented.

METHODS

Thirty-two men with invasive bladder carcinoma or recurrent carcinoma in situ underwent a radical cystectomy followed by orthotopic neobladder replacement using a right colonic, ileocolic or sigmoid colonic segment. The functional capacity, percentage of residual urine volume, configuration of the neobladder, and location in the pelvis were evaluated 1 year after surgery. Voiding function was evaluated using a questionnaire which included questions on diurnal and nocturnal continence, and by uroflowmetric analysis.

RESULTS

Operative time, blood loss, and functional neobladder capacity did not differ for the 3 types of neobladders. The configuration of the right colonic and ileocolic neobladders resembled the shape of a rugby ball. The configuration of the sigmoid neobladder was oval. The right colonic and ileocolic neobladders tended to be located along the right side wall of the pelvis. The sigmoid neobladder was located in the center of the pelvis. Daytime and nocturnal continence was not affected by either the type of neobladder or its configuration or position. Neobladders located in the center of the pelvis exhibited a better maximum flow rate than those located along the right wall of the pelvis.

CONCLUSION

The technical difficulty in constructing the 3 types of neobladders was approximately the same. For better voiding a neobladder should be located in the center of the pelvis.

Clinical evaluation of random biopsy of urinary bladder in patients with superficial bladder cancer

BACKGROUND

Superficial bladder cancer has a tendency to recur in the urinary bladder. One reason for recurrence is the presence of concomitant carcinoma in situ (CIS) or dysplasia. However, the usefulness of random biopsy of the urinary bladder has been unclear.

METHODS

Between September 1990 and March 1996, 83 patients with superficial bladder cancer underwent mucosal biopsy of 6 different sites in the urinary bladder with macroscopically normal findings (random biopsy). The relationship between a positive biopsy (CIS or dysplasia) and the tumor characteristics was examined. The disease-free survival of the patients according to the biopsy results was determined.

RESULTS

The positive biopsy rate was 24.1% (CIS, 14.5%; dysplasia, 9.6%). The incidence of positive biopsy in patients with high-grade (G3), pT1 tumors, 3 or more and non-papillary wide-based tumors was significantly higher than that in patients with 1 or 2 tumors, low-grade (G1, G2), pTa tumors and papillary tumors (P < 0.05). In patients with a single papillary tumor, positive biopsy was found in 9.5%. The disease-free survival in patients with a positive biopsy did not differ from that in patients with a negative biopsy, because intravesical bacillus Calmette-Guérin was instilled in patients with a positive biopsy.

CONCLUSION

Our results indicate that random biopsy is useful for detecting concomitant CIS or dysplasia and in the choice of drugs for intravesical instillation.

Pitfalls of measuring residual urine volume in orthotopic neobladders

OBJECTIVE

To investigate the pitfalls of measuring postvoid residual urine volume (PVR) in patients with orthotopic neobladders, in an out-patient clinic.

PATIENTS AND METHODS

Fifteen patients with orthotopic neobladders were enrolled in the study; five patients had a colonic neobladder, five an ileocolic neobladder and five a sigmoid neobladder. The PVR was compared after measuring by catheterization under fluoroscopic monitoring after normal or forced voiding.

RESULTS

The PVR after forced voiding was always less than that after natural voiding, regardless of the type of neobladder.

CONCLUSIONS

Patients with orthotopic neobladders may have a higher PVR after voiding naturally at home than when the PVR measured in hospital.

[A case of amyopathic dermatomyositis associated with interstitial pneumonitis]

A patient (47-year old female) who had erythema similar to Gottron's sign on bilateral finger joints since two years ago, started to have polyarthralgia on bilateral knee and shoulder on the spring of 1993. Polyarthralgia was extended to both wrist and hand joints on Oct. of 1995. On the middle of Dec. 1995, she began to have exertional dyspnea and was referred and admitted in our hospital on 18th, Dec., 1995. Chest X-ray and CT scan showed the shadow for active interstitial pneumonitis on bilateral lower lung fields. Blood gas analysis indicated hypoxia (PaO2: 62.8 mmHg) and low % DLCO (64.7%). Skin eruption of face (heliotrope-like erythema) and hands (Gottron's sign) and skin biopsy (right hand) findings were compatible with that in dermatomyositis. The analysis in blood biochemistry showed no elevation for muscle enzymes. The diagnosis for amyopathic dermatomyositis (ADM) was made according to the criteria proposed by Euwer & Sontheimer (1993). The steroid pulse therapy and 50 mg per day of cyclophosphamide were immediately administered. The dyspnea and dermatitis were improved within two weeks after therapy. She is presently in remission until Jan. 1997 with the maintenance dosis of 10 mg per day of oral prednisolone.

Recovery of leukocyte function after super-high-dose chemotherapy with peripheral blood stem cell transplantation in testicular cancer patients

Leukocyte functions (superoxide production and phagocytosis) were evaluated in patients with testicular cancer who had undergone super-high-dose chemotherapy (SHDT) with peripheral blood stem cell transplantation (PBSCT). In 5 patients with advanced or relapsed testicular cancer who received 8 cycles of SHDT with PBSCT, we measured superoxide production activity by phorbol myristate acetate (PMA) stimulation, as well as phagocytic activity using latex particles before and after PBSCT. The median time to reach a leukocyte count of > or = 1,000/microl was 9 days after PBSCT. Superoxide production activity was significantly decreased on day 7 compared with the pre-chemotherapy level. However, it recovered by day 12 and sustained such a level thereafter. Phagocytic activity was within the normal range on day 7 but declined slightly on days 12 and 21 compared with the pre-chemotherapy level. Our results indicate that leukocyte function and leukocyte count recover promptly following PBSCT and that PBSCT is a safe and convenient adjunctive therapy after SHDT for patients with advanced testicular cancer.

Basic fibroblast growth factor regulates matrix metalloproteinases production and in vitro invasiveness in human bladder cancer cell lines

PURPOSE

This study was designed to investigate the effect of endogenous basic fibroblast growth factor (FGF-2) on matrix metalloproteinases (MMPs) production and in vitro invasive potential of human bladder cancer cell lines.

MATERIALS AND METHODS

The human bladder cancer cell lines, HT1376 and KoTCC-1, were used in this study. The mRNA for FGF receptor has been shown to be expressed in both cell lines; the mRNA for FGF-2 is expressed in only KoTCC-1. The effects of FGF-2 expression on HT1376 by gene transfection and those of FGF-2 antisense oligonucleotides treatment on KoTCC-1 were analyzed by zymography and in vitro tumor cell invasion assay.

RESULTS

The introduction of human FGF-2 gene into HT1376 cells markedly enhanced both the MMP-2 and MMP-9 production, and the in vitro invasive potential was also increased. In contrast, the exposure of KoTCC-1 cells to FGF-2 specific antisense oligonucleotides decreased the MMP-2 production and in vitro invasive potential, but the exposure to FGF-2 sense oligonucleotides did not.

CONCLUSIONS

These findings suggest that FGF-2 plays an important role in the invasive process of human bladder cancer in part through the regulation of MMPs production.

Treatment of crush syndrome patients following the great Hanshin earthquake

Five of 8 patients with rhabdomyolysis treated at our hospital following the Great Hanshin Earthquake were diagnosed with crush syndrome. One patient with crush syndrome and 3 patients with rhabdomyolysis and no renal dysfunction recovered with conservative therapy, while 1 crush syndrome patient recovered with peritoneal dialysis (PD). Of the 3 patients who died, 2 had undergone continuous arterio-venous hemofiltration (CAVH). We examined the laboratory data to identify any factors that may be prognostic for crush syndrome. The serum amylase levels were significantly higher and the levels of aspartate transaminase (AST) and lactic dehydrogenase (LDH) tended to be higher from the patients who died. Examination of the serum amylase, AST and LDH levels may be useful for assessing the prognosis in patients with crush syndrome.

[Interaction between neurons and astrocytes involved in brain regulatory function as assessed by in vitro brain ischemia models]

In the recent decade of brain research, one of the most interesting findings is the significance of the active neuronal-glial interaction. It is no exaggeration to say that astrocytes in the central nervous system have an important role, participating in the regulation of neuronal functions. For instance, the fate of brain neurotransmitters, especially amino acids, following their release by neurons, is to be mainly inactivated by uptake via specific high-affinity transport systems into not only neuronal cells but also astrocytes, rather than by extracellular enzymatic degradation. These uptake mechanisms in astrocytes are very important for maintaining brain neuronal function under the low energy condition. In our research using the in vitro brain ischemia model, it was demonstrated that the neuronal death induced by excessive amounts of glutamate (Glu) under low energy conditions (hypoglycemia, hypoxia, particularly acidosis) is caused by dysfunctions of astrocyte Glu uptake and glutamine (Gln) output systems, and neural death can be modulated by the number of surrounding astrocytes in the cultured brain cells. Moreover, the neuronal dysfunction induced by excessive amounts of Glu was enhanced by a blocker of Glu uptake into astrocytes rather than an antagonist of Gln synthetase, which mainly exists in the astrocytes. During dysfunctions of astrocytes induced by acidosis, sustained increases of NO metabolites, ammonia and cytokines were produced. These biological substances may regulate the functions of neuronal cells and astrocytes. Thus, the balance of astrocyte-neuronal cells can maintain the brain neuronal homeostasis.

Percutaneous treatment of transitional cell carcinoma of the upper urinary tract

BACKGROUND

We evaluated the long-term effect of percutaneous resection in 2 Japanese patients with transitional cell carcinoma of the renal pelvis, and reviewed the medical literature on similar patients, to determine the appropriate indications for percutaneous treatment of transitional cell carcinoma in the upper urinary tract.

RESULTS

Indications for endoscopic resection in the 2 patients were renal insufficiency and unsuitability for major open surgery. The patients had no recurrence during follow-up. Seven previous reports described percutaneous resection of upper urinary tract transitional cell carcinoma in 82 patients. Although 72.6% of the patients were successfully treated by percutaneous resection, half of the patients with grade 3 carcinoma developed recurrence.

CONCLUSION

These results, together with those of the 7 published reports, suggest that percutaneous resection should be limited to selected patients with low-grade transitional cell carcinoma.

Immune response to a differentiation antigen induced by altered antigen: a study of tumor rejection and autoimmunity

Recognition of self is emerging as a theme for the immune recognition of human cancer. One question is whether the immune system can actively respond to normal tissue autoantigens expressed by cancer cells. A second but related question is whether immune recognition of tissue autoantigens can actually induce tumor rejection. To address these issues, a mouse model was developed to investigate immune responses to a melanocyte differentiation antigen, tyrosinase-related protein 1 (or gp75), which is the product of the brown locus. In mice, immunization with purified syngeneic gp75 or syngeneic cells expressing gp75 failed to elicit antibody or cytotoxic T-cell responses to gp75, even when different immune adjuvants and cytokines were included. However, immunization with altered sources of gp75 antigen, in the form of either syngeneic gp75 expressed in insect cells or human gp75, elicited autoantibodies to gp75. Immunized mice rejected metastatic melanomas and developed patchy depigmentation in their coats. These studies support a model of tolerance maintained to a melanocyte differentiation antigen where tolerance can be broken by presenting sources of altered antigen (e.g., homologous xenogeneic protein or protein expressed in insect cells). Immune responses induced with these sources of altered antigen reacted with various processed forms of native, syngeneic protein and could induce both tumor rejection and autoimmunity.

A melanosomal membrane protein is a cell surface target for melanoma therapy

Differentiation antigens on cancer cells are recognized by the immune system. A prototype set of these autoantigens in melanoma cells are the melanosomal glycoproteins, expressed in both melanomas and normal melanocytes. These are intracellular proteins that can be recognized by both antibodies and T lymphocytes. While one can understand how T cells can respond to intracellular proteins, based on cellular requirements for antigen processing and presentation, it is more difficult to understand how antibody responses to melanosomal proteins could lead to tumor rejection. We demonstrate that gp75 is expressed on the cell surface as well as intracellularly in human and mouse melanomas. The surface expression of gp75 can be augmented by IFN-gamma and during tumor growth in vivo. Surface expression of gp75 on mouse melanoma cells correlates with the ability of a monoclonal antibody (mAb) against gp75 to reject melanomas in syngeneic mice. Antibody-mediated rejection seems to require the Fc portion of the antibody, suggesting a role for Fc receptor-positive effector cells such as natural killer cells. However, although NK1.1(+) cells have been implicated in antibody-induced rejection in vivo, cell surface expression of gp75(+) on melanoma does not lead to susceptibility to antibody-dependent cellular cytotoxicity in vitro. The mAb to gp75 induced tumor rejection in mice carrying both scid and bg/bg traits, showing that neither thymus-dependent T cells nor natural killer cytotoxic activity was required in vivo. Long-term treatment of mice with mAb led to patchy depigmentation in the coat. In summary, an intracellular organellar protein can be expressed at the cell surface and provide an antigenic target for antibody therapy and autoimmunity.