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Biomedical subjects

Y Kakehi

Publications and source records attributed to Y Kakehi.

At least 19 recordsLinked to original sources
PubMed2006

Monoclonal antibody to tumor necrosis factor-related apoptosis-inducing ligand receptor 2 (TRAIL-R2) induces apoptosis in primary renal cell carcinoma cells in vitro and inhibits tumor growth in vivo.

Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) triggers apoptosis in a variety of tumor cells through two of its receptors: TRAIL-R1 and TRAIL-R2. We investigate the susceptibility of human renal cell carcinoma (RCC) cells to TRM-1 and HGS-ETR2, 2 human monoclonal agonistic antibodies specific for TRAIL-R1 and TRAIL-R2, respectively. HGS-ETR2 effectively induced apoptotic cell death in 10 of 11 cell cultures, including 2 human RCC cell lines and 9 human primary RCC cell cultures, with a more pronounced effect after preincubation with anti-human IgG Fc. In contrast, TRM-1 was effective in only 1 primary RCC cell culture. The increased effectiveness of HGS-ETR2 for inducing cell death might have been affected by differences in the cell-surface expression of the 2 TRAIL receptors, namely that TRAIL-R2 but not TRAIL-R1 was frequently expressed in most of the RCC cells tested. The activities of caspase-9, -8, -6, and -3 were increased with HGS-ETR2-induced apoptosis, and cell death could be blocked by specific caspase inhibitors for caspase-9, -8, and -3, and the general caspase inhibitor. In vivo administration of HGS-ETR2 with or without cross-linker significantly suppressed tumor growth of subcutaneously inoculated human RCC xenografts in immunodeficient mice. These results suggest the potential utility of TRAIL-R2 antibody as a novel therapeutic agent in RCC.

Animals↗
PubMed2004

Effective treatment of advanced solid tumors by the combination of arsenic trioxide and L-buthionine-sulfoximine.

Clinical application of anticancer agents has been often hampered by toxicity against normal cells, so the achievement of their cancer-specific action is still one of the major challenges to be addressed. Previously, we reported that arsenic trioxide (As2O3) could be a promising new drug against not only leukemia but also solid tumors. The cytotoxicity of As2O3 occurred through the generation of reactive oxygen species (ROS), thus inhibiting radical scavenging systems would enhance the therapeutic efficacy of As2O3 provided that normal cells were relatively resistant to such a measure. Here, we report that the combination therapy of As2O3 with L-buthionine-sulfoximine (BSO), which inhibits a critical step in glutathione synthesis, effectively enhanced in vitro growth inhibition effect of As2O3 on all 11 investigated cell lines arising from prostate, breast, lung, colon, cervix, bladder, and kidney cancers, compared with As2O3 treatment alone. Furthermore, this combination enhanced cytotoxicity to cell lines from prostate cancer with less toxicity to those from normal prostate. In vitro cytotoxic assay using ROS-related compounds demonstrated that hydrogen peroxide (H2O2) is a major cytotoxic mediator among ROS molecules. Biochemical analysis showed that combined use of As2O3 and BSO blocked H2O2-scavenging systems including glutathione, catalase, and glutathione peroxidase, and that the degree of this blockade was well correlated with intracellular ROS levels and sensitivity to this treatment. Finally, the effectiveness of the combination therapy of As2O3 with BSO was demonstrated with an orthotopic model of prostate cancer metastasis. We propose that the combination therapy of As2O3 with BSO is a valid means of blockade of H2O2-scavenging system, and that the combination of a ROS-generating agent with an inhibitor of major scavenging systems is effective in terms of both efficacy and selectivity. Furthermore, because the effective doses of both compounds are within clinically achievable range, this report will lead to immediate benefit for the development of a new cancer therapy.

Animals↗
PubMed2004

Enhancement of arsenic trioxide-induced apoptosis in renal cell carcinoma cells by L-buthionine sulfoximine.

Arsenic trioxide (As2O3) induces clinical remission in acute promyelocytic leukemic patients and apoptosis in various tumor cells in vitro. To develop As2O3-based combination chemotherapy for renal cell carcinoma (RCC), we investigated the cytotoxic effects of As2O3 in combination with chemotherapeutic agents or L-buthionine sulfoximine (BSO), a glutathione (GSH) synthesis inhibitor. Cytotoxicity and synergy were assessed by the MTT assay and isobolographic analysis, respectively. Apoptosis was monitored by Hoechst 33342 staining, flow cytometrical analysis, and DNA fragmentation assay. Treatment of ACHN cells with As2O3 in combination with adriamycin, vinblastine, or 5-fluorouracil induced an antagonistic effect. However, combination treatment with As2O3 and BSO resulted in a synergistic cytotoxic effect. Synergy was also obtained in Caki-1, Caki-2, NC65 cells and freshly derived RCC cells from 6 patients. Simultaneous treatment of ACHN cells with As2O3 and BSO caused significantly more cytotoxicity than the As2O3 first BSO second or the reverse treatment. We further explored the mechanisms underlying this synergistic effect and found that the synergistic cytotoxicity of As2O3 and BSO was realized by inducing apoptosis. This combination markedly decreased intracellular GSH content and GSH-S-transferase (GST) activity. However, neither the intracellular GSH nor GST was decreased by As2O3 with adriamycin, vinblastine, or 5-fluorouracil. Furthermore, the GSH-increasing agents N-acetylcysteine and lipoic acid significantly inhibited the combined cytotoxicity of As2O3 and BSO. These findings indicate that BSO sensitizes RCC cells to As2O3-induced apoptosis through the down-regulation of the intracellular GSH redox system, suggesting the potential application of a combination of As2O3 and BSO for the treatment of RCC.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2001

Tumor growth inhibition by arsenic trioxide (As2O3) in the orthotopic metastasis model of androgen-independent prostate cancer.

Arsenic trioxide (As2O3) induces clinical remission of patients with acute promyelocytic leukemia. As a novel anticancer agent for treatment of solid cancers, As2O3 is promising, but no in vivo experimental investigations of its efficacy on solid cancers have been done at clinically obtained concentrations. In addition, the cell death mechanism of As2O3 has yet to be clarified, especially in solid cancers. In this study, human androgen-independent prostate cancer cell lines, PC-3, DU-145, and TSU-PR1 were examined as cellular models for As2O3 treatment, and As2O3-induced cell death and inhibition of cell growth and colony formation were evaluated. The involvement of p38, c-Jun NH2-terminal kinase (JNK), caspase-3, and reactive oxygen species (ROS) were investigated in As2O3-induced cell death. Finally, As2O3 was administered to severe combined immunodeficient mice inoculated orthotopically with PC-3 cells to estimate in vivo efficacy. In all three of the cell lines, at high concentrations, As2O3 induced apoptosis and, at low concentrations, growth inhibition. As2O3 activated p38, JNK, and caspase-3 dose dependently. Treatment with the p38 inhibitor and over-expression of dominant-negative JNK did not guard against As2O3-induced cell death. In contrast with partial protection by the caspase-3 inhibitor, the antioxidant N-acetyl-L-cysteine gave marked protection from As2O3-induced apoptosis and eliminated the activation of p38, JNK, and caspase-3, and the generation of ROS. The orthotopic murine metastasis model showed in vivo tumor growth inhibition in orthotopic and metastatic lesions with no signs of toxicity. This study establishes that As2O3 provides a novel, safe approach for treatment of androgen-independent prostate cancer. Generation of ROS as a therapeutic target for the potentiation of As2O3-induced apoptosis also was shown.

Androgens↗
PubMed2001

Increased intracellular doxorubicin by anti-FAS monoclonal antibody: a mechanism that enhances the cytotoxicity in renal cell carcinoma cells.

OBJECTIVES: To investigate the effect of anti-Fas monoclonal antibody (mAb) on the intracellular concentration of doxorubicin in renal cell carcinoma (RCC) cells. Little is known about the influence of anti-Fas mAb on the intracellular concentration of chemotherapeutic agents. METHODS: The concentration of intracellular doxorubicin was determined by high-performance liquid chromatography. The mRNA and protein levels of multidrug resistance-associated protein gene were evaluated by reverse transcriptase-polymerase chain reaction and immunocytochemistry, respectively. RESULTS: An increased concentration of doxorubicin inside the cells was found: 2.4-fold in ACHN cells (a human RCC cell line) after treatment with doxorubicin combined with anti-Fas mAb compared with doxorubicin alone. Of the five cases of freshly derived RCC cells treated with doxorubicin and anti-Fas mAb, the intracellular concentration of doxorubicin was increased 2.3 and 2.7-fold in two of them, respectively. Furthermore, both the mRNA and the protein levels of the multidrug resistance-associated protein gene were downregulated after treatment of ACHN cells with anti-Fas mAb. Treatment of ACHN cells with a combination of anti-Fas mAb and doxorubicin resulted in a potentiation of the doxorubicin-mediated cytotoxicity. CONCLUSIONS: The increased intracellular concentration of doxorubicin by anti-Fas mAb might be one of the mechanisms responsible for the enhancement of doxorubicin-mediated cytotoxicity in RCC cells.

ATP-Binding Cassette Transporters↗
PubMed2001

Distinct microsatellite alterations in upper urinary tract tumors and subsequent bladder tumors.

PURPOSE: Although synchronous and/or metachronous tumor development is common in urothelial cancer, genetic and biological differences in upper urinary tract and bladder tumors are unclear. We compared the genetic alteration pattern in multifocal disease in patients with upper urinary tract and subsequent bladder tumors, and those with recurrent bladder tumor. MATERIALS AND METHODS: Using 21 microsatellite markers on the 8 chromosomal arms 2q, 4p, 4q, 8p, 9p, 9q, 11p and 17p we analyzed 34 tumors from 15 patients with upper urinary tract and subsequent bladder disease, and 70 tumors from 22 with recurrent bladder disease. RESULTS: Judging from the patterns of genetic alterations multifocal tumors were considered to have derived from an identical progenitor cell in 7 of 13 evaluable patients (54%) with upper urinary tract and subsequent bladder tumors, and 16 of 19 (84%) who were evaluable with recurrent bladder tumor. These data confirm the view that seeding or intraepithelial spread is a major mechanism for the multifocal development of urothelial cancer in general. However, a discordant microsatellite alteration pattern in multifocal tumors was observed in 6 of 7 patients (86%) with upper urinary tract and subsequent bladder lesions but in 2 of 16 (13%) with recurrent bladder cancer (p <0.005). CONCLUSIONS: Our results imply that upper urinary tract neoplasms may be genetically more unstable than bladder neoplasms. The implantation of tumor cells from upper urinary tract to bladder may involve additional and diverse genetic alterations. Furthermore, a considerable number of multifocal upper urinary tract and subsequent bladder lesions may arise independently via field cancerization mechanism. Our study indicates that the factors contributing to multifocal development are different in the 2 groups.

DNA, Satellite↗
PubMed2001

Activation of caspase-3 in renal cell carcinoma cells by anthracyclines or 5-fluorouracil.

The caspase family of proteases is speculated to have a crucial role in apoptosis. The effect of treatment with adriamycin (ADR), cisplatin (CDDP), 5-fluorouracil (5-FU), vinblastine (VLB), IFN-alpha, or IFN-gamma on the activation of caspase-3, -6, -8, and -9 in renal cell carcinoma (RCC) cells was investigated, to clarify the mechanisms of chemo- and immunotherapeutic agent-mediated apoptosis. Caspase activity was determined by a quantitative colorimetric assay. Apoptosis was monitored by acridine-orange staining assay. Treatment of ACHN cells with CDDP, VLB, IFN-alpha, or IFN-gamma did not activate caspase-3, but its activity was increased 7.2-fold (p = 0.0001) with ADR and 2.8-fold (p = 0.0385) with 5-FU in comparison with control. Furthermore, when the ADR treatment time was shortened from 24 to 8 or 2 h, the same caspase-3 activation occurred. Activation of caspase-3 was also observed in six freshly isolated human RCC cells after the treatment with ADR. Of the six freshly derived RCC cells treated with 5-FU, caspase-3 activity was increased 3.1-fold (p = 0.0051) and 2.4-fold (p = 0.0346) in two of them, respectively. Epirubicin and pirarubicin, compounds closely related to ADR, also respectively enhanced 4.2-fold (p = 0.0052) and 2.8-fold (p = 0.0147) caspase-3 activity in ACHN cells. The activation of caspase-3 observed with a colorimetric assay was confirmed with immunocytochemical analysis using the anti-active caspase-3 mAb, which specifically recognizes the active form of caspase-3. Furthermore, both active caspase-3 and apoptosis triggered by either ADR or 5-FU were inhibited significantly by the general caspase inhibitor Z-VAD-FMK, or a specific caspase-3 inhibitor DMQD-CHO. These findings provide a mechanistic explanation for anthracyclines and 5-FU induced-apoptosis.

Amino Acid Chloromethyl Ketones↗
PubMed2001

[A case of malignant fibrous histiocytoma arising from the renal capsule].

A 62-year-old man was admitted with a chief complaint of general malaise. Computed tomography showed a large mass adjacent to the parenchyma of the left kidney. The mass was 17 x 13 x 12 cm in size. Preoperative diagnosis was left renal cell carcinoma and left radical nephrectomy was performed. Histopathologically, the tumor was diagnosed as malignant fibrous histiocytoma (MFH), and the tumor was considered to have arisen from the renal capsule. There has been no recurrence for 7 months postoperatively. We review 40 cases of MFH arising from the kidney or the renal capsule in the literature.

Diagnosis, Differential↗
PubMed2001

[Progression from adenocarcinoma to small cell carcinoma of the prostate during endocrinotherapy: a case report].

A 72-year-old man had undergone surgical castration for metastatic prostate cancer (stage D2, the PSA value was 4,300 ng/ml) in September, 1997. He was well clinically for 16 months with undetected level of PSA. However, he presented with general malaise and gross hematuria in May, 1999. After admission to our hospital his condition rapidly deteriorated and he died one week later with respiratory failure. Autopsy revealed extensive involvement of the prostate and bladder by solid tumor with multiple metastases in lungs, liver, spleen, kidneys and bone. Histological examination revealed pure small cell carcinoma of the prostate.

Adenocarcinoma↗
PubMed2000

Rapid detection of candidate metastatic foci in the orthotopic inoculation model of androgen-sensitive prostate cancer cells introduced with green fluorescent protein.

BACKGROUND: An in vivo spontaneous metastatic model using androgen-sensitive prostate cancer cells is needed to the better understanding of prostate cancer progression. Orthotopically inoculated LNCaP cells to SCID mice manifests metastases, but it takes no less than 12 weeks to detect them by conventional methods. METHODS: The green fluorescent protein (GFP) gene was introduced into LNCaP cells by conventional lipofection technique. Biological characteristics of a subline (LNCaP-GFP) that expressed GFP at high level were compared to those of the parental cells. LNCaP-GFP cells were orthotopically inoculated to the SCID mouse, and metastases to distant organs were chronologically examined under fluorescence microscopy. RESULTS: There was no difference in growth rates and androgen-responsiveness in vitro between LNCaP-GFP and LNCaP cells. LNCaP-GFP cells inoculated to SCID mice produced prostate specific antigen. Histopathological examination at 12 weeks after inoculation of LNCaP-GFP revealed that metastases were identified as the inoculation of LNCaP cells. Colonies consisting of a few LNCaP-GFP cells, however, were detected in the lung under fluorescence microscopy as early as 4 weeks after inoculation. CONCLUSIONS: Orthotopic inoculation of LNCaP-GFP to SCID mice may provide a useful tool to investigate the molecular mechanism of progression, in particular the early stage of metastasis, of androgen-sensitive prostate cancer cells.

Androgens↗
PubMed2000

Suppression of pulmonary metastasis using adenovirally motility related protein-1 (MRP-1/CD9) gene delivery.

Previously we showed that MRP-1/CD9 might prevent tumor metastasis by suppression of cell motility and invasion of tissue barriers. The present study explored the possibility of preventing metastasis of mouse melanoma BL6 by expression of MRP-1/CD9 through gene transfer. A replication-deficient adenovirus vector was used for the in vivo transfer of MRP-1/CD9 cDNA. Intratumor injection of an adenovirus vector (rAd-MRP-1/CD9) expressing MRP-1/CD9 resulted in a 73.7% reduction in the number of pulmonary metastases of mice and the median survival time of mice treated with rAd-MRP-1/CD9 was significantly longer than those treated with the rAd-beta-gal vector (103.2 approximately plus;8.5 days vs 71.2 approximately plus;5.2 days, P<0.001 respectively). These results support the expression of MRP-1/CD9 through gene transfer as a therapeutic strategy for preventing metastases and prolonging survival, and support the feasibility of gene transfer in a clinically relevant setting.

Adenoviridae↗
PubMed2000

Increased risk of prostate cancer and benign prostatic hyperplasia associated with a CYP17 gene polymorphism with a gene dosage effect.

The CYP17 gene (CYP17) codes for the cytochrome P450c17alpha enzyme, which mediates two key steps in the sex steroid synthesis. There is a polymorphism (a T-to-C substitution) in the 5'-untranslated region, which may influence the transcription level of CYP17 mRNA. There is a continuing controversy as to whether the variant allele is associated with a subset of breast cancer or polycystic ovary syndrome. In prostate cancer research, there are contradictory data concerning the CYP17 risk allele. We explored the association between CYP17 polymorphism and a risk of prostate cancer or benign prostatic hyperplasia (BPH) in a Japanese population. This study included 252 prostate cancer patients, 202 BPH patients, and 131 male controls. A 451-bp fragment encompassing the polymorphic site was amplified by PCR, treated with restriction enzyme MspA1, and electrophoresed on an agarose gel. The MspA1-undigested allele with the published sequence and the MspA1-digested variant allele were designated as A1 and A2, respectively. There was a significant difference (P < 0.05) in the genotypes between prostate cancer patients and male controls, and between BPH patients and male controls. Men with the A1/A1 CYP17 genotype had an increased risk of prostate cancer [odds ratio (OR), 2.57; 95% confidence interval (CI) = 1.39-4.78] and BPH (OR, 2.44; 95% CI = 1.26-4.72) compared with those with the A2/A2 genotype. Men with the A1/A2 genotype had an intermediate increased risk of prostate cancer (OR, 1.45; 95% CI = 0.84-2.54) and BPH (OR, 1.60; 95% CI = 0.89-2.87) compared with those with the A2/A2 genotype. The trend of an increasing risk of prostate cancer and BPH with an increasing number of the A1 allele was statistically significant (prostate cancer versus male control, P = 0.003; OR, 1.57; 95% CI = 1.16-2.12; BPH versus male control, P = 0.008; OR, 1.55; 95% CI = 1.12-2.13). There was no significant association between the CYP17 genotype and the tumor status (grade and stage) of prostate cancer. Our results suggest that the A1 allele of the CYP17 polymorphism is associated with an increased risk of prostate cancer and BPH, with a gene dosage effect. However, the CYP17 genotype does not seem to influence the disease status in prostate cancer.

Aged↗
PubMed2000

Molecular diagnosis of metastatic origin in a patient with metachronous multiple cancers of the renal pelvis and bladder.

It is not uncommon for patients with urothelial cancer to have synchronous and metachronous multifocal invasive tumors of the bladder and upper urinary tract. If a metastatic lesion becomes evident in such a patient, the origin of the metastasis is often not determinable using conventional histopathologic examination of the surgical or autopsy specimen. Here, we report a patient in whom the clonal relationship among the histologically undistinguishable multifocal urothelial cancers and metastatic tumors could be clarified by molecular genetic analysis. Furthermore, the potential role for each genetic alteration in the multifocal and metastatic tumor development and the treatment efficacy for each multifocal tumor were also clearly demonstrated.

Carcinoma, Transitional Cell↗
PubMed2000

Enhancement of Fas-mediated apoptosis in renal cell carcinoma cells by adriamycin.

Anti-Fas monoclonal antibody (mAb) kills Fas-expressing cells by apoptosis. Several anticancer agents also mediate apoptosis and may share common intracellular pathways leading to apoptosis with Fas. Thus, we reasoned that combination treatment of drug-resistant cells with anti-Fas mAb and drugs might overcome their resistance. We investigated whether anticancer agents enhance Fas-mediated apoptosis and cytotoxicity against renal cell carcinoma (RCC) cells. Treatment of ACHN RCC cells with anti-Fas mAb in combination with 5-fluorouracil, vinblastine, IFN-alpha, or IFN-gamma did not overcome resistance to these agents. However, combination treatment with anti-Fas mAb and Adriamycin (ADR) resulted in a synergistic cytotoxic effect. Furthermore, synergy was also obtained even when the exposure time was shortened from 24 h to 8 or 2 h. Synergy was also achieved in four other RCC cell lines and five freshly derived human RCC cells. Treatment with anti-Fas mAb in combination with epirubicin or pirarubicin also resulted in a synergistic cytotoxic effect on ACHN cells. Similar results were achieved with a combination of humanized anti-Fas mAb and ADR. Incubation of ACHN cells with ADR augmented the expression of Fas and p53, but not Bcl-2, Bax, or caspase-3. However, the activity of caspase-3 itself was apparently enhanced after treatment with ADR alone or combined treatment with anti-Fas mAb. The synergy obtained in cytotoxicity with anti-Fas mAb and ADR was also achieved in apoptosis. Exposure of ACHN cells and freshly derived RCC cells to ADR enhanced their susceptibility to lysis by peripheral blood lymphocytes and tumor-infiltrating lymphocytes. This study demonstrates that combination treatment of RCC cells with anti-Fas mAb and ADR might overcome their resistance. The sensitization required a low concentration of ADR and a short exposure time, thus supporting the potential in vivo application of a combination of ADR and anti-Fas mAb or immunotherapy in the treatment of ADR- and/or immunotherapy-resistant RCC.

Acridine Orange↗
PubMed2000

CROP/Luc7A, a novel serine/arginine-rich nuclear protein, isolated from cisplatin-resistant cell line.

A novel putative SR protein, designated cisplatin resistance-associated overexpressed protein (CROP), has been cloned from cisplatin-resistant cell lines by differential display. The N-half of the deduced amino acid sequence of 432 amino acids of CROP contains cysteine/histidine motifs and leucine zipper-like repeats. The C-half consists mostly of charged and polar amino acids: arginine (58 residues or 25%), glutamate (36 residues or 16%), serine (35 residues or 15%), lysine (30 residues, 13%), and aspartate (20 residues or 9%). The C-half is extremely hydrophilic and comprises domains rich in lysine and glutamate residues, rich in alternating arginine and glutamate residues, and rich in arginine and serine residues. The arginine/serine-rich domain is dominated by a series of 8 amino acid imperfect repetitive motif (consensus sequence, Ser-Arg-Ser-Arg-Asp/Glu-Arg-Arg-Arg), which has been found in RNA splicing factors. The RNase protection assay and Western blotting analysis indicate that the expression of CROP is about 2-3-fold higher in mRNA and protein levels in cisplatin-resistant ACHN/CDDP cells than in host ACHN cells. CROP is the human homologue of yeast Luc7p, which is supposed to be involved in 5'-splice site recognition and is essential for vegetative growth.

Amino Acid Sequence↗
PubMed2000

Use of pretreatment prostate-specific antigen doubling time to predict outcome after radical prostatectomy.

The objective of this study was to better understand the implications of the rate of prostate-specific antigen (PSA) changes in prostate carcinoma. We retrospectively calculated PSA doubling times prior to surgery in 62 patients with prostate carcinoma. The calculated values were compared with final pathologic findings and with rates of PSA failure after surgery. PSA values increased during the period of observation in 82.3% of the patients, whereas 17.7% had levels that remained stable. The median calculated PSA doubling time in those with increasing levels was 25.8 months, with doubling times </=24 months observed in 37.1% of the patients. Stage pT3 disease was more common in patients with PSA doubling times of </=36 months than in those with doubling times >36 months (P=0.02). Biochemical failure was more common in patients with rapid PSA doubling times (P<0.01). The calculated PSA doubling time prior to radical surgery is significantly associated with the final pathologic findings. Early PSA failure is more common in patients with rapid PSA doubling times prior to radical surgery. Prostate Cancer and Prostatic Diseases (2000) 3, 269-274

Journal Article↗
PubMed2000

Telomerase activity in urine after transurethral resection of superficial bladder cancer and early recurrence.

BACKGROUND: To explore the relationship between telomerase activity in urine after transurethral resection (TUR) of superficial bladder cancer and early intravesical recurrence. METHODS: Urine samples were obtained from 42 patients with superficial bladder cancers prior to TUR and on the postoperative day 1 and day 6. These patients were followed-up prospectively by cystoscopy at 3 and 6 months after TUR in combination with urinary cytology and telomerase activity. Telomerase activity in the urine was assessed by the telomeric repeat amplification protocol assay. RESULTS: Urinary telomerase activity prior to TUR was positive in 24 (57%) of the 42 patients. On the postoperative day 1 and day 6, positive urinary telomerase activity was seen in 13 (31%) and nine (21%) patients, respectively. Postoperative urinary telomerase activity on either day 1 or day 6 was significantly associated with pre-operative urinary telomerase activity status (P = 0.0024). Fifteen patients showed intravesical tumor recurrence at 3 months cystoscopic check-up and an additional nine had recurred at the 6 months check-up. Recurrence rate within 6 months in patients with pre-operative positive urinary telomerase activity was similar to that in those with negative activity (58.3 vs 58.8%). However, recurrence rate at 3 months for patients with positive activity was higher than that of those with negative activity (50 vs 17.7%), in 23 patients treated only by TUR. CONCLUSIONS: Presence of cells positive for telomerase activity in urine after TUR of superficial bladder cancer indicates persistently existing cancer cells in the urine. It is, however, not a sole predictor of the early intravesical recurrence.

Adult↗