Shinichi Ikemoto

Antitumor effects of Scutellariae radix and its components baicalein, baicalin, and wogonin on bladder cancer cell lines

OBJECTIVES To investigate the antitumor effects of Scutellariae radix and its components baicalein, baicalin, and wogonin on human bladder cancer cell lines (KU-1 and EJ-1) and a murine bladder cancer cell line (MBT-2). METHODS Bladder cancer cells were incubated with various concentrations of the agents. Antiproliferative activity against the bladder cancer cell lines was examined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diplenyl tetrazolium bromide assay. In an in vivo experiment, the mice were subcutaneously injected with MBT-2 cells, and Scutellariae radix was orally administered at a dose of 2 or 10 mg per mouse one time daily for 10 days from day 11 to day 20. RESULTS All the drugs inhibited cell proliferation in a dose-dependent manner, but baicalin exhibited the greatest antiproliferative activity. The concentration of baicalin necessary to obtain 50% inhibition was 3.4 microg/mL for KU-1, 4.4 microg/mL for EJ-1, and 0.93 microg/mL for MBT-2. For KU-1 and MBT-2, the percentage of cell survival significantly decreased (P <0.05) at a baicalin concentration of 1 microg/mL. In an in vivo experiment, antitumor effects of Scutellariae radix on C3H/HeN mice implanted with MBT-2 were investigated. All the control mice showed a progressive increase in tumor volume, reaching 2.81 +/- 0.18 cm(3) on day 20 and 5.36 +/- 0.44 cm(3) on day 25. However, when Scutellariae radix was orally administered at a dose of 10 mg per mouse one time daily for 10 days from day 11 to day 20, the tumor volume was 1.99 +/- 0.19 cm(3) on day 20 and 3.86 +/- 0.26 cm(3) on day 25, a significant inhibition of tumor growth (P <0.05). Conclusions. These results suggest that Chinese herbal medicines may become an attractive and promising treatment for bladder cancer.

Interleukin-6, tumour necrosis factor α and interleukin-1β in patients with renal cell carcinoma

As regulators of malignant cell behaviour and communication with stroma, cytokines have proved useful in understanding cancer biology and developing novel therapies. In renal cell carcinoma, patients with inflammatory reactions are known to have poor prognosis. In order to elucidate the relation between renal cell carcinoma and the host, serum levels of inflammatory cytokines, interleukin-6, tumour necrosis factor α, interleukin-1β, were measured. One hundred and twenty-two patients with renal cell carcinoma and 21 healthy control subjects were studied, and serum cytokine levels were measured using a highly sensitive ELISA kit. As a result, in the control group, interleukin-6, tumour necrosis factor α and interleukin-1β levels were 1.79±2.03, 2.74±0.94 and 0.16±0.17 pg ml−1, respectively. In the renal cell carcinoma patients, they were 8.91±13.12, 8.44±4.15 and 0.53±0.57 pg ml−1, respectively, and significantly higher. In the comparison of stage, interleukin-6 level was significantly higher in the stage IV group compared to the other stage groups including the control group, while tumour necrosis factor α level was significantly higher in each stage group compared to the control group. As for grade, interleukin-6 level was significantly higher in the grade 3 group compared to the control, grade 1 and grade 2 groups, while tumour necrosis factor α level was significantly higher in each grade group compared to the control group. All cytokines had a positive correlation with tumour size. In regard to the correlation with CRP, all cytokines had a positive correlation with CRP, while interleukin-6 had a particularly strong correlation. In conclusion, interleukin-6 may be one of the factors for the poor prognosis of patients with renal cell carcinoma. In addition, tumour necrosis factor α may be useful in the early diagnosis of renal cell carcinoma and post-operative follow-up.

Interleukin-6, tumour necrosis factor alpha and interleukin-1beta in patients with renal cell carcinoma.

As regulators of malignant cell behaviour and communication with stroma, cytokines have proved useful in understanding cancer biology and developing novel therapies. In renal cell carcinoma, patients with inflammatory reactions are known to have poor prognosis. In order to elucidate the relation between renal cell carcinoma and the host, serum levels of inflammatory cytokines, interleukin-6, tumour necrosis factor α, interleukin-1β, were measured. One hundred and twenty-two patients with renal cell carcinoma and 21 healthy control subjects were studied, and serum cytokine levels were measured using a highly sensitive ELISA kit. As a result, in the control group, interleukin-6, tumour necrosis factor α and interleukin-1β levels were 1.79±2.03, 2.74±0.94 and 0.16±0.17 pg ml−1, respectively. In the renal cell carcinoma patients, they were 8.91±13.12, 8.44±4.15 and 0.53±0.57 pg ml−1, respectively, and significantly higher. In the comparison of stage, interleukin-6 level was significantly higher in the stage IV group compared to the other stage groups including the control group, while tumour necrosis factor α level was significantly higher in each stage group compared to the control group. As for grade, interleukin-6 level was significantly higher in the grade 3 group compared to the control, grade 1 and grade 2 groups, while tumour necrosis factor α level was significantly higher in each grade group compared to the control group. All cytokines had a positive correlation with tumour size. In regard to the correlation with CRP, all cytokines had a positive correlation with CRP, while interleukin-6 had a particularly strong correlation. In conclusion, interleukin-6 may be one of the factors for the poor prognosis of patients with renal cell carcinoma. In addition, tumour necrosis factor α may be useful in the early diagnosis of renal cell carcinoma and post-operative follow-up.

Androgen regulation of CYP4B1 responsible for mutagenic activation of bladder carcinogens in the rat bladder: detection of CYP4B1 mRNA by competitive reverse transcription-polymerase chain reaction

Significant sex differences exist among cases of bladder cancer in humans as well as in experimental animals such as rats. Aromatic amines such as benzidine and 2-naphthylamine are known to induce bladder cancer. These carcinogenic amines are activated to genotoxic substances by cytochrome P 450 CYP4B1, which is present in bladder mucosa. In this study, regulation of CYP4B1 was investigated to elucidate sex difference in bladder carcinogenesis. Competitive reverse transcription-polymerase chain reaction was used to investigate the expression of rat CYP4B1 mRNA occurring in small amounts of tissue such as bladder tissue. Expression of CYP4B1 in the bladder of male rats increased with development but not in that of female rats. Moreover, mature male rats exhibited higher expression of CYP4B1 in the bladder than did mature female rats. Castration of male rats decreased CYP4B1 levels and treatment with testosterone led to a partial recovery of CYP4B1 levels. These results indicate that CYP4B1 levels in the rat bladder are partly regulated by androgens. Furthermore, the present findings suggest that the sex difference observed in bladder carcinogenesis was due to sex-different expression of CYP4B1 in bladder tissue.

Mutagenic activation of aflatoxin B1 by pulmonary, renal, and hepatic cytochrome P450s from rats

The genotoxic and mutagenic activation of aflatoxin B1 (AFB1) by hepatic, renal, and pulmonary microsomes and purified cytochrome P450s was investigated in Salmonella typhimurium TA1535/pSK1002 cells in which an umu response shows DNA damage. The activity of the hepatic microsomes was greatest. Pulmonary microsomes had moderate activity and renal microsomes had low activity. P450 2C11, 2B1, 3A2, 4A2, 4B1, K-2, and K-4 were assayed in a reconstituted system with dilauroylphosphatidylcholine (DLPC). P450 2C11 (a major hepatic cytochrome P450 in male rats) had high activity. P450 2B1 (a major form as well as P450 4B1 in pulmonary microsomes) and K-2 (a minor form in renal microsomes) had moderate activity. P450 4A2 (a major form in renal microsomes), P450 K-4 (a renal form), and P450 4B1 had low activity. P450 3A2 did not have high activity in these conditions but it had high activity toward AFB1 in a modified reconstituted system with a lipid mixture and sodium cholate instead of DLPC only. The activities of other forms were not enhanced by the modification of reconstituted system. Anti-P450 2C11 or 3A2 antibodies inhibited the bioactivation of AFB1 by hepatic microsomes to 50%. These results suggest that the greater ability of hepatic microsomes as compared with pulmonary and renal microsomes to metabolize AFB1 to mutagenic products is a function of the relative proportions of the highly active cytochrome P450s, P450 2C11 and 3A2, in the liver.

Correlation of tumor necrosis factor and prostaglandin E2 production of monocytes in bladder cancer patients

Patients with advanced malignant neoplasms have a variety of abnormal monocyte and lymphocyte functions. The authors examined tumor necrosis factor (TNF) and prostaglandin E2 (PGE2) production of monocytes in 48 patients with bladder cancer and 16 control subjects. Monocytes were isolated from peripheral blood mononuclear cells by adherence to plastic tissue. They were cultured with lipopolysac‐charide for 24 hours, and the culture supernatant was obtained. The TNF was measured by enzyme immunoassay using anti‐recombinant human TNF antibody, and PGE2 was measured by radioimmunoassay. As a result, in high‐stage bladder cancer patients, there was a significant inverse correlation between TNF and PGE2 production of monocytes. However, there was no significant correlation in control subjects and low stage patients. Accordingly, some patients with high‐stage bladder cancer had higher TNF production but lower PGE2 production of monocytes, and vice versa.

Microscopic hematuria as a screening marker for urinary tract malignancies

Abstract Background: Although a mass screening urinalysis is a widely accepted procedure, it has not yet been shown if microhematuria is an appropriate and useful screening marker for urologic malignancies.

Are tobacco use and urine pH indicated as risk factors for bladder carcinoma

Abstract Background: Many case‐control and cohort studies have shown a positive relationship between bladder carcinoma and tobacco use. Recently, urine pH has been reported to influence aromatic amine carcinogenesis, which have been implicated as potent carcinogens in bladder carcinoma patients. Herein the correlation between bladder carcinoma, tobacco use and urine pH is reported.

Comparative Antitumor Activity of 5-Fluorouracil and 5’-Deoxy-5-Fluorouridine in Combination with Interferon-α in Renal Cell Carcinoma Cell Lines

Objectives: Although interferon-α (IFNα) and interleukin-2 are used in the treatment of advanced renal cell carcinoma (RCC), the rate of efficacy is about 15% and not satisfactory. Therefore, a more effective treatment is being investigated. In this study, we examined the combined effects of IFNα and 5-fluorouracil (5-FU) as well as 5-deoxy-5-fluorouridine (5′-DFUR), a produrg of 5-FU, in vitro. Materials and Methods: Four RCC cell lines (OCUU1, OCUU3, OCUU4, OCUU5) were established at our laboratory from RCC patients. OS-RC-2, RCC10RGB, TUHR14TKB, TUHR4TKB, A498 and Caki-1 were obtained from a commercial source. The sensitivity of the 10 RCC cell lines to 5-FU and 5′-DFUR was evaluated using MTT assay. The IC50 value for the cytostatics was expressed as the concentration at which growth was inhibited by 50% as compared with the control value. Thymidine phosphorylase (TP), the enzyme that converts 5′-DFUR into 5-FU and 5-FU into FdUMP, was estimated by ELISA. Results: When the 10 RCC cell lines were divided into the low TP expression group and high TP expression group at 2.0 U/ml protein, TP expression was not enhanced by IFNα in all 4 cell lines in the low TP expression group. Antitumor effects were not enhanced by IFNα in 3 out of 4 cell lines for 5-FU and in all 4 cell lines for 5′-DFUR. On the other hand, in the high TP expression group, TP expression was enhanced by IFNα in 5 out of 6 cell lines, and antitumor effects were enhanced by IFNα in 5 out of 6 cell lines for 5-FU and in all 6 cell lines for 5′-DFUR. In addition, there was a significant correlation between TP expression and sensitivity to 5-FU and 5′-DFUR in all RCC cell lines. Conclusions: These results suggested that TP may be useful as a predictive factor in combination therapy with IFNα and 5-FU or 5′-DFUR, which may be a promising treatment for advanced RCC.

Expression of hepatic microsomal cytochrome P450s as altered by uremia

The proportions of different hepatic microsomal cytochrome P450s expressed in uremic rats were studied with specific antibodies and with a steroid hydroxylase assay. In male uremic rats, the hepatic levels of P450 2C11, a male-specific form, and 3A2, a male-dominant form, were decreased to about 30% at 5 weeks after the induction of uremia. These changes were paralleled by decreases in the activities of testosterone 2 alpha-, 16 alpha-, and 6 beta-hydroxylation. The level of P450 2A1, abundant in immature rats, was increased 2-fold by uremia and accompanied by an increase in testosterone 7 alpha-hydroxylation activity. The levels of P450 2C6 and 2E1 were not changed by uremia. The levels of male-specific and male-dominant forms such as P450 2C11 and 3A2 are affected by the serum level of testosterone, which was decreased in the male rats with uremia. Therefore, castrated rats were prepared to compare the effects of testosterone on hepatic cytochrome P450s in uremic rats with those in castrated rats. When testosterone was administered to the castrated rats, the decreased levels of both P450 2C11 and 3A2 returned to normal. However, the administration of testosterone to the uremic rats did not prevent the decrease in the levels of these P450s. In female rats, changes in the levels of cytochrome P450s were not as great during uremia as those in male uremic rats. The level of P450 2C12, a female-specific form, was not changed; the level of P450 2A1 was increased by 50%, that of 3A2 which is barely detected in female rats was increased by 60%, and that of 2E1 was increased by 25%. These results suggested that the changes in the hepatic levels of cytochrome P450s were affected by factors other than testosterone in uremic rats.