Nobumichi Tanaka

Heme oxygenase-1 promotes angiogenesis in urothelial carcinoma of the urinary bladder

Angiogenesis is necessary for the growth, invasion, and metastasis of solid tumors. Previous studies have shown that heme oxygenase-1 (HO-1) plays an important role in angiogenesis in both normal and cancerous cells, such as vascular endothelial cells and pancreatic cancer cells, respectively. In this study, we analyzed the role of HO-1 and other angiogenic factors in urothelial carcinoma of the bladder. Specifically, we used real-time reverse transcription polymerase chain reaction (PCR) and Western blotting to investigate the upregulation of 7 angiogenic factors, namely, HO-1, vascular endothelial growth factor (VEGF), hypoxia-inducible factor (HIF)-1α, HIF-2α, cyclooxygenase-2 (COX-2), interleukin-8 (IL-8), and basic fibroblast growth factor (bFGF) under hypoxic conditions in the T24 urothelial carcinoma cell line. We also used enzyme-linked immunosorbent assay (ELISA) to measure the amount of VEGF secreted into the growth media. In addition, we administered an HO-1 inhibitor, zinc protoporphyrin IX, to mice with subcutaneous T24 tumors to assess the modulation of angiogenesis in solid tumors in vivo. We also performed immunohistochemical analyses of 23 primary bladder cancer specimens with high-grade tumors infiltrating into the stroma (pT1) for expression of HO-1, VEGF, HIF-1α, HIF-2α, COX-2, and CD31. Image analysis of CD31 staining was performed to estimate microvessel density (MVD), a measure of angiogenesis. Hypoxic conditions induced upregulation of HO-1, VEGF, HIF-1α, HIF-2α, and COX-2 in T24 cells and increased VEGF secretion, which could be suppressed by zinc protoporphyrin IX. In vivo, inhibition of HO-1 decreased tumor growth and MVD by suppressing angiogenic factors, particularly VEGF and HIF-1α. In clinical specimens of bladder cancer, high expression of HO-1 was correlated with high expression of HIF-1α (P=0.027) and high MVD (P=0.005), but not with VEGF expression (P=0.19). In conclusion, since overexpression of HO-1 promotes angiogenesis in urothelial carcinoma cells, HO-1 inhibitors could be used as novel therapeutics for urothelial carcinoma of the urinary bladder.

Prognostic factors of renal cell carcinoma with extension into inferior vena cava

Objective:  To evaluate the prognosis of our series of patients with renal cell carcinoma (RCC) and tumor thrombus involving inferior vena cava (IVC) treated with nephrectomy and thrombectomy.

Inhibition of COX-2 expression by topical diclofenac enhanced radiation sensitivity via enhancement of TRAIL in human prostate adenocarcinoma xenograft model

BackgroundCOX-2 inhibitors have an antitumor potential and have been verified by many researchers. Treatment of cancer cells with external stressors such as irradiation can stimulate the over-expression of COX-2 and possibly confer radiation resistance. In this study, we tested if topical diclofenac, which inhibits both COX-1 and COX-2, administration rendered prostate tumor cells sensitize to the effects of radiation.MethodsLNCaP-COX-2 and LNCaP-Neo cells were treated with 0 to 1000 μM diclofenac. Next, a clonogenic assay was performed in which cells were subjected to irradiation (0 to 4 Gy) with or without diclofenac. COX-2 expression and other relevant molecules were measured by real-time PCR and immunohistochemistry after irradiation and diclofenac treatment. In addition, we assessed the tumor volumes of xenograft LNCaP-COX-2 cells treated with topical diclofenac with or without radiation therapy (RT).ResultsLNCaP-COX-2 and LNCaP-Neo cell lines experienced cytotoxic effects of diclofenac in a dose related manner. Clonogenic assays demonstrated that LNCaP-COX-2 cells were significantly more resistant to RT than LNCaP-Neo cells. Furthermore, the addition of diclofenac sensitized LNCaP-COX-2 not but LNCaP-Neo cells to the cytocidal effects of radiation. In LNCaP-COX-2 cells, diclofenac enhanced radiation-induced apoptosis compared with RT alone. This phenomenon might be attributed to enhancement of RT-induced TRAIL expression as demonstrated by real-time PCR analysis. Lastly, tumor volumes of LNCaP-COX-2 cells xenograft treated with diclofenac or RT alone was >4-fold higher than in mice treated with combined diclofenac and radiation (p<0.05).ConclusionsThese in vitro and in vivo findings suggest that conventional COX inhibitor, diclofenac enhances the effect of RT on prostate cancer cells that express COX-2. Thus, diclofenac may have potential as radiosensitizer for treatment of prostate cancer.

Function of JunB in Transient Amplifying Cell Senescence and Progression of Human Prostate Cancer

Purpose: Replicative senescence in cells acts as a barrier against excessive proliferation and carcinogenesis. Transient amplifying cells (TAC) are a subset of basal cell populations within the prostate from which cancers are thought to originate; therefore, we focused on prostate TAC to investigate the molecular mechanisms by which the TAC may be able to evade senescence. Experimental Design: TAC clones were isolated from each zone within the whole prostate and analyzed in flow cytometry. Prostate cancer cells were transfected with junB small interfering RNA (siRNA) and examined by chorioallantoic membrane assay for cancer invasion. Immunohistochemical analysis was done in primary and metastatic prostate cancer specimens. Results: TAC populations showed increased expression of p53, p21, p16, and pRb, resulting in senescence. TAC clones with reduced p16 expression successfully bypassed this phase. We further found close correlation between the levels of junB and p16 expression. Repeated transfection of junB siRNA in prostatic TAC allowed the cells to escape senescence presumably through inactivation of p16/pRb. The chorioallantoic membrane invasion assay showed much lower in invasive cancer cells with high expression of junB; conversely, silencing of junB by transfection with junB siRNA promoted invasion. We also found that metastatic prostate cancers, as well as cancers with high Gleason scores, showed significantly low junB immunopositivity. Conclusions: JunB is an essential upstream regulator of p16 and contributes to maintain cell senescence that blocks malignant transformation of TAC. JunB thus apparently plays an important role in controlling prostate carcinogenesis and may be a new target for cancer prevention and therapy.

Risk Factors for New-onset Overactive Bladder in Older Subjects: Results of the Fujiwara-Kyo Study

OBJECTIVE To evaluate the risk factors for new-onset overactive bladder (OAB) in older subjects. METHODS The present study enrolled 4427 subjects aged ≥ 65 years who had participated in the Fujiwara-kyo study. The prevalence of OAB at baseline and 1 year later was evaluated using the OAB symptom score questionnaire. The incidence and remission rate of OAB were calculated. We identified the risk factors for OAB by evaluating the difference in characteristics (including sex, age, body mass index, life style, comorbidities, depressive status, metabolic syndrome, and sum of voiding symptoms) between those with and without new-onset OAB. In addition, the independent risk factors were determined by multivariate analysis. RESULTS Of the 4427 subjects, 3685 completely replied to the self-administrated questionnaires at baseline and 1 year later. The incidence and remission rate of OAB was 11.9% and 29.8%, respectively. The male/female ratio, sum of voiding symptoms, alcohol consumption and smoking, hypertension, and depressive status in subjects with new-onset OAB, were significantly greater than those in subjects without new-onset OAB. A multivariate analysis, including sex (odds ratio 2.0, P < .0001), sum of voiding symptoms (odds ratio 1.1, P < .0001), and depressive status (odds ratio 1.8, P < .0001) were independent factors for new-onset OAB in older subjects. CONCLUSION The results of the present study have demonstrated that male sex, the sum of voiding symptoms, and depression were independent factors for new-onset OAB. It is necessary to determine whether the treatment of patients with voiding symptoms or depression controls for new-onset OAB.

Clinical Significance of Heme Oxygenase-1 Expression in Non-Muscle-Invasive Bladder Cancer

Introduction: In several malignant diseases, elevated heme oxygenase-1 (HO-1) is associated with progression or resistance to chemotherapy. We evaluated the clinical significance of HO-1 expression in non-muscle-invasive bladder cancer. Patients and Methods: We examined 109 patients with non-muscle-invasive bladder cancer. The immunoexpression of HO-1, p53, and Ki-67 was analyzed using paraffin-embedded tissue from transurethral resection in comparison with the clinicopathological variables. Results: Positive expression of HO-1 was found in 66 of 109 tumors (61%), and the positivity of HO-1 correlated significantly with high tumor grade and the altered expression patterns of p53 and Ki-67. In our analysis of 16 cases treated by intravesical administration of anthracyclines, the positive expression of HO-1 correlated with poor disease-free survival (p = 0.015). In in vitro experiments using urothelial cancer cell lines, HO-1 upregulation was observed by exposure to doxorubicin. Moreover, siRNA-mediated suppression of HO-1 upregulation sensitized the urothelial cancer cells to doxorubicin. Conclusions: Our findings suggested that resistance against anthracyclines correlated with HO-1 and expression analysis of HO-1 may be a useful predictive marker for intravesical administration of anthracyclines.

Diagnostic usefulness of endorectal magnetic resonance imaging with dynamic contrast-enhancement in patients with localized prostate cancer: mapping studies with biopsy specimens.

Background : New diagnostic criteria for dynamic magnetic resonance (MR) imaging in prostate cancer are presented. The diagnostic usefulness of endorectal MR imaging with dynamic contrast‐enhancement in localized prostate cancer and the validity of these criteria were evaluated.

Syndecan‐1 (CD138) contributes to prostate cancer progression by stabilizing tumour‐initiating cells

Increasing evidence suggests that tumour‐initiating cells (TICs) contribute to the development of prostate cancer. Here, we identified syndecan‐1 as a key molecule maintaining the stability of prostate cancer TICs. Holoclones harbouring the biological properties of stemness were derived from single‐cell cultures of the PC3 human prostate cancer cell line. These holoclones over‐expressed syndecan‐1, but showed reduced expression of NADPH oxidase (NOX) and synthesis of hydrogen peroxide and oxygen radicals. Stable RNA‐mediated silencing of syndecan‐1 gene expression up‐regulated NOX‐dependent generation of reactive oxygen species and reduced the survival of holoclones in vitro. Syndecan‐1 down‐regulation also strongly reduced the number of CD133+/CD44+ primitive cancer cells and tumour growth in vivo. Interestingly, syndecan‐1 gene knockdown significantly enhanced the tumour‐suppressive effects of docetaxel by inhibiting the docetaxel‐induced increase in CD133+/CD44+ cells in vivo. In the transgenic adenocarcinoma of the mouse prostate (TRAMP) mouse model of prostate cancer, early intervention with a syndecan‐1 inhibitor (OGT2115) or syndecan‐1 RNAi reduced the incidence of adenocarcinoma and the number of c‐kit+/CD44+ cells in cancer foci. Finally, we found that syndecan‐1 immunopositivity in prostate cancer cells was significantly associated with biochemical recurrence after radical prostatectomy. Taken together, our results show that syndecan‐1 contributes to prostatic carcinogenesis by maintaining TICs and may be a target molecule for therapy. Copyright

Hydrodistension under local anesthesia for patients with suspected painful bladder syndrome/interstitial cystitis: safety, diagnostic potential and therapeutic efficacy.

Objectives:  To evaluate the safety, diagnostic potential and therapeutic efficacy of cystoscopy with hydrodistension under local anesthesia in patients with suspected painful bladder syndrome/interstitial cystitis (PBS/IC).

Immunohistochemical analysis of inflammatory cells in benign and precancerous lesions and carcinoma of the prostate.

Objective: Inflammation is an important cause of tumorigenesis in various types of malignancy. Mediators derived from inflammatory cells are associated with cancer proliferation, angiogenesis, and DNA damage. In the present study, we immunohistochemically examined the infiltration patterns of inflammatory cells in benign glands including glandular hyperplasia, and in prostatic intraepithelial neoplasia and adenocarcinoma. Methods: Formalin-fixed, paraffin-embedded tissues were obtained from 100 patients with prostate cancer. All patients underwent radical prostatectomy. We assessed the number of infiltrating T cells (CD3+), B cells (CD20+, CD79alpha+), and macrophages (CD68+, CD204+) in benign and malignant prostate tumors. Results: CD68+ macrophages infiltrated benign glands to a higher extent than those of adenocarcinoma. In contrast, the number of CD204+ cells was higher in malignant glands than in benign glands. There was no significant difference in the number of infiltrating T cells between benign and malignant tumors; however, the number of infiltrating B cells was significantly reduced in malignant glands. Conclusions: Inflammation of the prostate may act on prostate carcinomas; particularly that involving M2 macrophage infiltration may play a significant role in prostate carcinogenesis.