Hayahito Nomi

Adipose-derived stromal cells inhibit prostate cancer cell proliferation inducing apoptosis.

Mesenchymal stem cells (MSCs) have generated a great deal of interest in the field of regenerative medicine. Adipose-derived stromal cells (AdSCs) are known to exhibit extensive proliferation potential and can undergo multilineage differentiation, sharing similar characteristics to bone marrow-derived MSCs. However, as the effect of AdSCs on tumor growth has not been studied sufficiently, we assessed the degree to which AdSCs affect the proliferation of prostate cancer (PCa) cell. Human AdSCs exerted an inhibitory effect on the proliferation of androgen-responsive (LNCaP) and androgen-nonresponsive (PC3) human PCa cells, while normal human dermal fibroblasts (NHDFs) did not, and in fact promoted PCa cell proliferation to a degree. Moreover, AdSCs induced apoptosis of LNCaP cells and PC3 cells, activating the caspase3/7 signaling pathway. cDNA microarray analysis suggested that AdSC-induced apoptosis in both LNCaP and PC3 cells was related to the TGF-β signaling pathway. Consistent with our in vitro observations, local transplantation of AdSCs delayed the growth of tumors derived from both LNCaP- and PC3-xenografts in immunodeficient mice. This is the first preclinical study to have directly demonstrated that AdSC-induced PCa cell apoptosis may occur via the TGF-β signaling pathway, irrespective of androgen-responsiveness. Since autologous AdSCs can be easily isolated from adipose tissue without any ethical concerns, we suggest that therapy with these cells could be a novel approach for patients with PCa.

Incidence of urethral stricture after bipolar transurethral resection of the prostate using TURis: results from a randomised trial

To assess whether bipolar transurethral resection of the prostate (B‐TURP) using the TURis® system has a similar level of efficacy and safety to that of the traditional monopolar transurethral resection of the prostate (M‐TURP), and to evaluate the impact of the TURis system on postoperative urethral stricture rates over a 36‐month follow‐up period.

Acute Rejection of Allografted CTL-Susceptible Leukemia Cells from Perforin/Fas Ligand Double-Deficient Mice

The generation of knockout mice demonstrated that CD4+, but not CD8+, T cells were essential for the rejection of allografted skin or heart, presumably because these targets were CTL resistant. In the case of CTL-susceptible targets (e.g., P815 mastocytoma cells and EL-4 or RLmale1 T lymphoma cells), however, it is assumed that the CTL is the effector cell responsible for allograft rejection and that perforin and Fas ligand (FasL) pathways are the killing mechanisms. In the present study, we examined the role of these cytotoxic molecules in the rejection of i.p. allografted CTL-susceptible leukemia cells. Unexpectedly, the allografted leukemia cells were acutely rejected from gld (a mutation of FasL), perforin−/−, or double-deficient mice. The peritoneal exudate cells from gld or normal mice showed T cell-, TCRαβ-, and perforin-dependent cytotoxic activity against the allograft, whereas the exudate cells from perforin−/− mice exhibited almost full cytotoxic activity in the presence of Fas-Fc. Furthermore, the infiltrates from double-deficient mice showed a high cytotoxic activity against the allografted cells even in the presence of anti-TCRαβ Ab or in the absence of T cells. The cytotoxic cells appeared to be macrophages, because they were Mac-1+ mononuclear cells with a kidney- or horseshoe-shaped nucleus and because the cytotoxic activity was completely suppressed by the addition of NG-monomethyl-l-arginine, an inhibitor of inducible NO synthase. These results indicate that macrophages are ready and available to kill CTL-susceptible allografts when CTLs lack both perforin and FasL molecules.

Infiltration of H-2d-specific cytotoxic macrophage with unique morphology into rejection site of allografted meth A (H-2d) tumor cells in C57BL/6 (H-2b) mice

It is assumed that CD8+ cytotoxic T lymphocytes (CTLs) mediate direct lysis of allografts and that their growth, differentiation, and activation are dependent upon cytokine production by CD4+ helper T lymphocytes. In the present study, the effector cells responsible for the rejection of i.p. allografted, CTL‐resistant Meth A tumor cells from C57BL/6 mice were characterized. The cytotoxic activity was associated exclusively with peritoneal exudate cells and not with the cells in lymphoid organs or blood. On day 8, when the cytotoxic activity reached a peak, 3 types of cells (i.e., lymphocytes, granulocytes, and macrophages) infiltrated into the rejection site; and allograft‐induced macrophages (AIM) were cytotoxic against the allograft Bacterially‐elicited macrophages also exhibited cytotoxic activity (≈1/2 of that of AIM) against Meth A cells, whereas the cytotoxic activity of AIM against these cells but not that of bacterially‐elicited macrophages was completely inhibited by the addition of donor (H‐2d)‐type lymphoblasts, suggesting H‐2d‐specific cytotoxicity of AIM against Meth A cells. In contrast, resident macrophages were inactive toward Meth A cells. Morphologically, the three‐dimensional appearance of AIM showed them to be unique large elongated cells having radiating peripheral filopodia and long cord‐like extensions arising from their cytoplasmic surfaces. The ultrastructural examination of AIM revealed free ribosomes in their cytoplasm, which was often deformed by numerous large digestive vacuoles. These results indicate that AIM are the H‐2d‐specific effector cells for allografted Meth A cells and are a more fully activated macrophage with unique morphological features.

Essential Role of Monocytes in the In Vitro Production of IL-4 and Nonspecific IgE Antibody by Peripheral Blood Lymphocytes from Mice Sensitized s.c. Once with Cedar Pollen

To explore which cytokine or cell is essential for the production of antibodies (Abs) of the IgE class in allergic diseases, we injected cedar pollen into wild-type, interferon-gamma(-/-) (IFN-gamma(/)), or interleukin-4(-/-) (IL-4(-/-)) BALB/c mice through four (i.n., i.p., s.c., and i.v.) different routes without adjuvant. Wild-type or IFN-gamma(-/-), but not IL-4(-/-), mice sensitized once or twice showed a significant increase in total IgE Ab in their serum, revealing the essential role of IL-4 in the production of total IgE Ab. We separated peripheral blood mononuclear cells (PBMCs) from untreated or sensitized mice into monocyte-rich, lymphocyte-rich, and granulocyterich populations by Percoll density-gradient centrifugation or into specific antigen cells by flow cytometry, cultured the cells in various combinations, and examined the levels of cytokines and IgE Ab released into the medium. The PBMCs from mice sensitized s.c. once, but not those from untreated animals, produced significant amounts of IL-4 and total IgE Ab, whereas the lymphocyte-rich population alone did not. Unexpectedly, IL-4 and IgE Ab production was restored by the addition of Mac-1(+) cells in the monocyte-rich fraction to the lymphocyte-rich fraction. These results indicate the essential role of monocytes in the production of IL-4 and total IgE Ab by lymphocytes during the initial stage of sensitization.

Novel Bladder Preservation Therapy with Osaka Medical College Regimen

PURPOSE We investigated the effect of balloon occluded arterial infusion of an anticancer agent (cisplatin/gemcitabine), used concomitantly with hemodialysis, which delivers an extremely high concentration of anticancer agent to the tumor site without systemic adverse effects, along with concurrent radiation (referred to as the Osaka Medical College regimen) in patients with advanced bladder cancer. MATERIALS AND METHODS A total of 329 patients (TisN0 16, T2N0 174, T3N0 77, T4N0 22 and TxN+ 40) were assigned to receive the Osaka Medical College regimen. Patients who did not achieve complete response underwent total cystectomy or secondary balloon occluded arterial infusion with an increased amount of cisplatin and/or gemcitabine. RESULTS The Osaka Medical College regimen allowed 83.6% (276 of 329) of patients in total and 93.6% (250 of 267) of patients with organ confined disease (including T3b) to achieve complete response. Of the patients with a complete response 96% (240 of 250) survived with a functional bladder without evidence of recurrent disease within a mean followup of 159 weeks. Although lymph node involvement, especially N2 stage, was selected as a significant risk factor for treatment failure and survival, it was noteworthy that 61.9% of patients with N1 disease achieved complete response and that the 5-year overall survival rate was 72.2%. No patients had grade III or more severe toxicities. CONCLUSIONS The Osaka Medical College regimen, a new bladder preservation strategy, can be curative not only in patients for whom cystectomy is indicated, but also in patients whose condition is not amenable to curative treatment because of disease stage, age or other factors, and for whom merely palliative therapy would otherwise seem the only option.

Effect of a novel bladder preservation therapy, BOAI-CDDP-radiation (OMC-regimen)

We have developed a novel form of bladder preservation therapy [OMC (Osaka Medical College)-regimen] involving balloon-occluded-arterial-infusion (BOAI) of an anticancer agent (cisplatin/gemcitabine), used concomitantly with hemodialysis, which delivers an extremely high concentration of anticancer agent to the site of a tumor without systemic adverse effects, along with concurrent radiation. We previously reported that the OMC-regimen elicited a complete response (CR) in >90% of patients with organ confined tumors, while LN(+), T4 tumors and a non-UC histological type were statistically significant risk factors for treatment failure and patient survival. In this study, we investigated the effects of the OMC-regimen in patients with organ confined urothelial cancer tumors and the outcomes were compared to those with total cystectomy. Three hundred and one patients were assigned to receive either the OMC-regimen (n=162) or total cystectomy (n=139). Patients in the OMC-regimen group who failed to achieve CR underwent cystectomy, or secondary BOAI with an increased amount of CDDP or gemcitabine (1600 mg). The OMC-regimen yielded 98.1% of clinical response; CR in 93.8% (152/162) of patients; PR in 4.3% (7/162). More than 96% of the CR patients (146/152) were alive with no evidence of recurrence after a mean follow-up of 166 (range 23-960) weeks. No patients suffered grade III toxicity; all patients successfully completed this therapy. The patient survival was significantly better compared to the cystectomy group; the overall 5-, 10- and 15-year survival rates were 87.3, 79.6 and 59.7%, respectively. Moreover, the 5-, 10- and 15-year bladder intact survival rates, the most important issue for bladder preservation therapy, were 85.7, 78.4 and 58.8%, respectively. In conclusion, the OMC-regimen is a useful bladder-preservation strategy, not only in those for whom cystectomy is indicated, but also in patients whose condition is not amenable to curative treatment and for whom palliation would otherwise seem the only option.

IL-4-dependent induction of IgE+ basophils in peripheral blood and IgE+ B cells in spleen as respective indicators of allergen sensitization and a precursor of cells secreting allergen-specific IgE antibody

It was recently reported by us that either primary i.n. or i.p. injection of cedar pollen extract into BALB/c mice, or a second s.c. injection of the allergen into i.v. or s.c. sensitized mice, causes an IL‐4‐dependent increase in total IgE serum antibody to produce allergen‐specific IgE antibody upon further s.c. sensitization. To determine the biology of total IgE antibody, in the present study IgE+ cells in peripheral blood or lymphoid tissues of allergen‐sensitized BALB/c mice have been characterized. In peripheral blood, mice sensitized one to three times with the allergen produced a 2.5‐ to 4‐fold increase in the number of IgE+ cells, with a time‐course similar to that of the concentration of total IgE antibody in serum. These IgE+ cells were basophils. On the other hand, the number of IgE+ cells in the lymphoid tissues did not change significantly after an i.n., i.p., i.v. or s.c. injection of allergen into the mice, whereas a second s.c. injection of the allergen into the i.v.‐, but not into the i.n.‐, i.p.‐ or s.c.‐, sensitized mice induced a small number of IgE+/IgM+/B220+ B cells in the spleen. In contrast, IgE+ cells were not seen in the blood or spleen of IL‐4 ‐/‐ mice after sensitization with the allergen.

Induction of donor-specific tolerance using superagonistic CD28 antibody in rat renal allografts: regulatory T-cell expansion before engraftment may be important.

Background. We hypothesized that a superagonistic monoclonal antibody specific for CD28 (CD28SA), which expands regulatory T cells (Tregs) in vivo, would prevent acute rejection and prolong the survival of renal allograft. Methods. We examined whether CD28SA treatment induce donor-specific tolerance using our established rat renal allograft model (Wistar-Lewis). Results. All control rats died within 13 days because of severe azotemia with marked destruction of graft tissue. In contrast, recipients treated with a triple injection of CD28SA (days −3, 0, and 3) showed good preservation of graft histology and function, with considerable infiltration of Tregs into the allografts; 92% of recipients survived for more than 100 days, and 77% survived by the day of harvest at 180 days. These long-surviving recipients received secondary heterotopic bicardiac allografts from both donor-matched Wistar and third-party Brown Norway rats simultaneously 120 days after kidney transplantation, and seven of eight (87.5%) rats exhibited donor-specific tolerance, accepting the Wistar heart, but acutely rejecting the Brown Norway heart. Interestingly, a single injection of CD28SA 3 days before (day −3), but not 3 days after (day 3), transplantation also induced donor-specific tolerance in some recipients. We then performed adoptive transfer of nonspecific CD4+CD25+ Tregs, purified from CD28SA-treated Lewis rats, with simultaneous injection of hepatocyte growth factor (500 &mgr;g/kg/day, intravenously). The treatment induced significant prolongation of graft survival (P<0.0001 vs. control group), and five of eight (62.5%) recipients survived until the day of harvest at 180 days with successful induction of donor-specific tolerance. Conclusions. We have established a novel therapeutic approach for inducing donor-specific tolerance in rats with renal allografts.

The Anti-Proliferative Effect of Boron Neutron Capture Therapy in a Prostate Cancer Xenograft Model

Purpose Boron neutron capture therapy (BNCT) is a selective radiation treatment for tumors that preferentially accumulate drugs carrying the stable boron isotope, 10B. BNCT has been evaluated clinically as an alternative to conventional radiation therapy for the treatment of brain tumors, and more recently, recurrent advanced head and neck cancer. Here we investigated the effect of BNCT on prostate cancer (PCa) using an in vivo mouse xenograft model that we have developed. Materials and Methods Mice bearing the xenotransplanted androgen-independent human PCa cell line, PC3, were divided into four groups: Group 1: untreated controls; Group 2: Boronophenylalanine (BPA); Group 3: neutron; Group 4: BPA-mediated BNCT. We compared xenograft growth among these groups, and the body weight and any motility disturbance were recorded. Immunohistochemical (IHC) studies of the proliferation marker, Ki-67, and TUNEL staining were performed 9 weeks after treatment. Results The in vivo studies demonstrated that BPA-mediated BNCT significantly delayed tumor growth in comparison with the other groups, without any severe adverse events. There was a significant difference in the rate of freedom from gait abnormalities between the BPA-mediated BNCT group and the other groups. The IHC studies revealed that BNCT treatment significantly reduced the number of Ki-67-positive cells in comparison with the controls (mean±SD 6.9±1.5 vs 12.7±4.0, p<0.05), while there was no difference in the number of apoptotic cells, suggesting that BPA-mediated BNCT reduced PCa progression without affecting apoptosis at 9 weeks post-treatment. Conclusions This study has provided the first preclinical proof-of-principle data to indicate that BPA-mediated BNCT reduces the in vivo growth of PCa. Although further studies will be necessary, BNCT might be a novel potential treatment for PCa.