Biomedical subjects

T Imao

Publications and source records attributed to T Imao.

18 recordsLinked to original sources

PubMed2001

[A case of septic shock due to ileal conduit obstruction].

A 70-year-old man with bladder cancer received a total cystectomy and an ileal conduit 64 months before he visited our hospital with complaints of lower abdominal pain, shaking and chilliness. Bilateral hydronephrosis due to an ileal conduit obstruction were observed on the ultrasonography. Bacterial culture from blood and urine samplings revealed E. coli. Under the diagnosis of urosepsis, the administration of anti-biotics and bilateral percutaneous nephrostomy were performed. However, he suffered from septic shock and disseminated intravascular coagulation (DIC). Therefore, the treatments for DIC were done, and they were effective. The obstruction of the ileal conduit was cured spontaneously. No recurrence or metastases were found on ultrasonography and computed tomographic scan for 12 months after these treatments.

Aged↗

PubMed2001

[Primary small cell carcinoma of the kidney: a case report].

A 43-year-old male visited our hospital with the complaint of right flank colicky pain. Computed tomographic (CT)-scan and angiography showed large renal tumor with liver invasion and tumor thrombosis in the vena cava. Multiple lung and bone tumors were also recognized. Percutaneous biopsy of the renal tumor revealed small cell carcinoma. Multiple lung masses were diagnosed as metastatic tumors according to the results of bronchoscopic biopsy. Chemotherapy including cisplatinum and etoposide was performed without success. He died 6 months after the diagnosis. Autopsy specimen revealed primary small cell carcinoma of the right kidney. To our knowledge, this is the seventh case as primary renal small cell carcinoma in the world literature.

Adult↗

PubMed2001

[Prospects for molecular research in urological oncology: bladder cancer].

This report consists of a description of our research findings relating to the mechanism of cancer metastasis and target molecules for early diagnosis or cancer therapy. First, we investigated the significance of metastasis-related genes expressed to various extents in three human bladder cancer cell lines using two in vivo models. The relationship between the gene expression pattern and the behavior of cancer cells implicated a loss of E-cadherin expression as a critical factor in facilitating the progression of bladder cancer. Second, we examined the expression of human telomerase reverse transcriptase (hTERT) mRNA in voided urine samples in patients with bladder cancer. Reverse transcription-polymerase chain reaction (RT-PCR) analysis showed a higher positive rate as compared with cytological examination, suggesting that the expression of hTERT in urine samples may be a useful diagnostic marker for bladder cancer. Finally, we searched for a molecule to which antisense can be applied as a treatment modality. The 150 kDa oxygen regulated protein (ORP 150), a kind of heat shock proteins, functions as a molecular chaperone in the endoplasmic reticulum. We demonstrated that the adenoviral-mediated antisense ORP150 cDNA transfer resulted in the suppression of vascular endothelial growth factor (VEGF) expression and tumor growth in vivo. In addition, the significant correlation between ORP150 and matrix metalloproteinase 2 (MMP-2) expression was observed in bladder cancer, suggesting that ORP150 functions as a molecular chaperon to MMP-2 secretion for tumor invasion. Anti-sense ORP150 may therefore have a potentially stronger antitumor effect because of its multitargeting capability as a molecular chaperone.

Animals↗

PubMed2000

[A case of ileus as a late complication of an ileal conduit in a patient with primary signet ring cell carcinoma of the bladder].

A 69-year-old man visited our hospital with a complaint of dysuria. Intravenous excretory urography, ultrasonography and CT scan showed a tumor at the base of the bladder and the prostate. Transrectal needle biopsy revealed signet ring cell carcinoma. Radical cystectomy and ileal conduit were performed, and a histological diagnosis was a primary signet ring cell carcinoma of the bladder. No recurrence or metastasis was found either on ultrasonography or CT scan at 26 months after the operation. He suddenly suffered from severe abdominal pain, and died of hypovolemic shock by ileus as a late complication of an ileal conduit at 27 months after the operation. An ileus with extensive necrosis of small intestine and cancer recurrence at the junction of the ureter and ileal conduit were observed at autopsy.

Aged↗

PubMed1999

Dominant role of E-cadherin in the progression of bladder cancer.

PURPOSE: To elucidate factors with a role in the progression of bladder cancer. MATERIALS AND METHODS: One invasive (T24) and two superficial (RT4 and KK47) human bladder cancer cell lines, which express metastasis-related genes, were used. Cells were intravenously inoculated into chick embryos to evaluate metastatic potential to the liver. An orthotopic model with severe combined immunodeficiency mice was also used to investigate both histological appearance and changes in metastasis-related gene expression. Finally, gene expression patterns in a clinical setting were compared between superficial and invasive bladder cancers. RESULTS: In culture condition metastasis-related genes, including matrix metalloproteinases, urokinase-type plasminogen activator, and integrins alpha2 and alpha3 were continually expressed in T24 but only slightly or not at all in RT4 and KK47, respectively. The expression pattern of the metastasis-related genes in vitro reflected the characteristics of the original tumors. Liver metastasis in chick embryos was demonstrated not only with T24 cells, but also with RT4 cells in which enhanced expression of metastasis-related genes was induced. In the orthotopic model, histological appearances were in accordance with the characteristics of the original tumors, although enhanced gene expression was notable with RT4. Expression of E-cadherin by Western blotting was demonstrated only with RT4 under these experimental conditions. Furthermore, predominant E-cadherin mRNA expression was found in superficial and not in invasive human primary bladder cancers; expression of other genes was similar in the two groups. Dominant expression of E-cadherin in superficial tumors was confirmed by immunohistochemical analysis. CONCLUSIONS: These results implicate loss of E-cadherin expression as a critical factor in facilitating the progression of bladder cancer.

Animals↗

PubMed1998

Immunolocalization of anti-placental alkaline phosphatase monoclonal antibody in mice with testicular tumors and lymph node metastasis.

To evaluate the ability of an anti-placental alkaline phosphatase (PLAP) monoclonal antibody (MAb) to localize to PLAP-expressing tumors, we established a model of testicular tumor with metastasis to lymph nodes and liver in severe combined immunodeficient (SCID) mice. 131I-labeled or 125I-labeled MAb was simultaneously administered via the intravenous or lymphatic route, respectively. Preferential accumulation of MAb in PLAP-expressing tumors at primary as well as metastatic sites was demonstrated. The percentage of the injected dose of MAb found in the tumor was generally higher when MAb was administered intravenously. Identical tumor/blood ratios were found with the two routes of administration. These data suggest that intravenous administration of a radiolabeled MAb is superior to lymphatic administration for tumor imaging and radioimmunotherapy.

Alkaline Phosphatase↗

PubMed1998

Natural interferon enhances expression of placental alkaline phosphatase in human seminoma xenograft.

The purpose of this study was to investigate the effect of natural interferon (IFN) on the expression of placental alkaline phosphatase (PLAP) in a human seminoma xenograft in severe combined immunodeficient mice. Mice were injected intramuscularly with 3x10(5) U/mouse of IFN, twice a day, for five consecutive days. A significant increase in PLAP level of the xenografts followed IFN treatment. A radiolabeled anti-PLAP monoclonal antibody (MAb) was intravenously injected on the first day of IFN administration in order to determine if IFN has the potential to enhance the efficacy of an anti-PLAP MAb in the detection of seminoma. Enhanced retention of the anti-PLAP MAb was observed at 7 and 11 days after MAb administration. Thus, IFN treatment appears to have some effect on the efficacy of the anti-PLAP MAb in the detection of seminoma xenografts.

Alkaline Phosphatase↗

PubMed1998

Chemotherapy of metastatic testicular germ cell tumors: relationship of histologic response to size reduction and changes in tumor markers.

BACKGROUND: Although testicular germ cell tumor is one of the most curable cancers, approximately 20% of advanced cases remain incurable. In this study we investigate factors that may predict a poor response to standard chemotherapeutic regimens and thus allow earlier initiation of more aggressive measures. METHODS: We analyzed the records of 19 patients with metastatic testicular germ cell tumors (8 seminomas and 11 nonseminomas). Sixteen patients underwent surgical exploration for residual tumors following chemotherapy, and the histological findings on the resulting specimens were correlated with reductions in tumor size observed on computed tomography and with changes in tumor marker levels. RESULTS: Complete necrosis was obtained in 10 of 12 lesions that shrank by at least 80%, while continued existence of teratoma or cancer was confirmed in 9 of 11 lesions with smaller size reductions. An initial human chorionic gonadotropin-beta subunit (HCG-beta) level more than 100 times the upper limit of normal appeared to predict poor histological response (teratoma/cancer) to chemotherapy. Slow fall (prolonged half-life) of tumor markers during chemotherapy also correlated with poor histological response. CONCLUSION: Factors which predict poor histological response of tumors to chemotherapy include size reduction less than 80%, initial HCG-beta levels more than 100 times the upper limit of normal, and prolonged half-life of tumor markers (placental alkaline phosphatase, alpha-fetoprotein and HCG-beta).

Antineoplastic Combined Chemotherapy Protocols↗

PubMed1998

A chick embryo model for metastatic human prostate cancer.

OBJECTIVE: To establish a suitable experimental model of bone and liver micrometastases from human prostate cancer for evaluating antitumor agents. METHODS: PC-3 cells, an androgen-independent prostate cancer cell line, were inoculated into the chorioallantoic membrane vein of 10-day-old chick embryos (10(6) cells/egg). The polymerase chain reaction product for the human beta-globin gene in chick embryo femur and liver was quantified at various time points after inoculation, when immunohistochemical staining was done for Ki-67 antigen and cytokeratin. The antitumor effect of suramin was evaluated using the model, as was regional blood flow after thallium injection. RESULTS: Micrometastases were identified in bone and liver 1 day after inoculation and grew to form established metastatic foci in all embryos. Suramin showed significant antitumor effect for liver metastases, but not for those in bone where blood flow was relatively low. CONCLUSION: The chick embryo system provides a highly reproducible model for bone and liver micrometastases from human prostate cancer, suitable for evaluating antineoplastic agents at an early stage of the metastatic process.

Animals↗

PubMed1996

Melanotic neuroectodermal tumor of infancy in the epididymis. Case report and literature review.

We report a case of melanotic neuroectodermal tumor that originated in the right epididymis of a 4-month-old Japanese male and review reports of similar cases. Since we could not exclude malignant disease preoperatively, we performed a radical orchiectomy. Histopathological and immunohistochemical studies revealed features characteristic of a melanotic neuroectodermal tumor. Imaging studies showed no distant metastases.

Epididymis↗

PubMed1972