-
[show abstract]
[hide abstract]
ABSTRACT: PurposeThe proper induction of cellular immunity is required for effective bacillus Calmette-Guérin (BCG) immunotherapy of bladder
cancer. It has been known that BCG stimulation of human peripheral blood mononuclear cells (PBMC) leads to the generation
of effector cells cytotoxic to bladder cancer cells in vitro. To improve BCG therapy, we previously developed human interferon
(IFN)-α 2B secreting recombinant (r) BCG (rBCG-IFN-α). We demonstrated that rBCG-IFN-α augmented T helper type 1 (Th1) cytokine
IFN-γ production by PBMC. In this study, we further investigated whether rBCG-IFN-α could also enhance PBMC cytotoxicity toward
bladder cancer cells.
Materials and methodsPBMC were prepared from healthy individuals, left alone or stimulated with rBCG-IFN-α or control MV261 BCG, and used as effector
cells in 51Cr-release assays. Human bladder cancer cell lines T24, J82, 5637, TCCSUP, and UMUC-3 were used as target cells. To determine
the role of secreted rIFN-α as well as endogenously expressed IFN-γ and IL-2 in inducing the cytotoxicity, PBMC were stimulated
with rBCG-IFN-α in the presence of neutralizing antibodies to IFN-α, IFN-γ or IL-2. To determine the role of natural killer
(NK) and CD8+ T cells in inducing the cytotoxicity, both cell types were isolated after BCG stimulation of PBMC and used as effector cells
in 51Cr-release assays.
ResultsNon-stimulated PBMC showed basal levels of cytotoxicity against all target cell lines tested. MV261 BCG increased the PBMC
cytotoxicity by 1.8- to 4.2-fold. rBCG-IFN-α further increased the PBMC cytotoxicity by up to 2-fold. Elevated production
of IFN-γ and IL-2 by PBMC was observed after rBCG-IFN-α stimulation. Blockage of IFN-α, IFN-γ or IL-2 by neutralizing antibodies
during rBCG-IFN-α stimulation reduced or abolished the induction of PBMC cytotoxicity. Both NK and CD8+ T cells were found to be responsible for the enhanced PBMC cytotoxicity induced by rBCG-IFN-α with the former cell type being
more predominant.
ConclusionsrBCG-IFN-α is an improved BCG agent that induces enhanced PBMC cytotoxicity against bladder cancer cells in vitro. This rBCG
strain may serve as an alternative to BCG for the treatment of superficial bladder cancer.
Cancer Immunology and Immunotherapy 04/2012; 58(10):1647-1655. · 3.70 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Intravesical instillation of Mycobacterium bovis bacillus Calmette-Guérin (BCG) has been used for treating bladder cancer for 3 decades. However, BCG therapy is ineffective in approximately 30-40% of cases. Since evidence supports the T helper type 1 (Th1) response to be essential in BCG-induced tumor destruction, studies have focused on enhancing BCG induction of Th1 immune responses. Although BCG in combination with Th1 cytokines (e.g., interferon-α) has demonstrated improved efficacy, combination therapy requires multiple applications and a large quantity of cytokines. On the other hand, genetic manipulation of BCG to secrete Th1 cytokines continues to be pursued with considerable interest. To date, a number of recombinant BCG (rBCG) strains capable of secreting functional Th1 cytokines have been developed and demonstrated to be superior to BCG. This paper discusses current rBCG research, concerns, and future directions with an intention to inspire the development of this very promising immunotherapeutic modality for bladder cancer.
Clinical and Developmental Immunology 01/2011; 2011:728930. · 1.84 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: New animal models are greatly needed in interstitial cystitis/painful bladder syndrome (IC/PBS) research. We recently developed a novel transgenic cystitis model (URO-OVA mice) that mimics certain key aspects of IC/PBS pathophysiology. This paper aimed to determine whether URO-OVA cystitis model was responsive to intravesical dimethyl sulfoxide (DMSO) and if so identify the mechanisms of DMSO action. URO-OVA mice developed acute cystitis upon adoptive transfer of OVA-specific OT-I splenocytes. Compared to PBS-treated bladders, the bladders treated with 50% DMSO exhibited markedly reduced bladder histopathology and expression of various inflammatory factor mRNAs. Intravesical DMSO treatment also effectively inhibited bladder inflammation in a spontaneous chronic cystitis model (URO-OVA/OT-I mice). Studies further revealed that DMSO could impair effector T cells in a dose-dependent manner in vitro. Taken together, our results suggest that intravesical DMSO improves the bladder histopathology of IC/PBS patients because of its ability to interfere with multiple inflammatory and bladder cell types.
Journal of Biomedicine and Biotechnology 01/2011; 2011:937061. · 2.44 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Many details of the molecular and cellular mechanisms involved in Mycobacterium bovis bacillus Calmette-Guérin (BCG) immunotherapy of bladder cancer have been discovered in the past decades. However, information on a potential role for macrophage cytotoxicity as an effector mechanism is limited. Macrophages play pivotal roles in the host innate immunity and serve as a first line of defense in mycobacterial infection. In addition to their function as professional antigen-presenting cells, the tumoricidal activity of macrophages has also been studied with considerable interest. Studies have shown that activated macrophages are potent in killing malignant cells of various tissue origins. This review summarizes the current understanding of the BCG-induced macrophage cytotoxicity toward bladder cancer cells with an intention to inspire investigation on this important but underdeveloped research field.
Clinical and Developmental Immunology 01/2010; 2010:357591. · 1.84 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The proper induction of cellular immunity is required for effective bacillus Calmette-Guérin (BCG) immunotherapy of bladder cancer. It has been known that BCG stimulation of human peripheral blood mononuclear cells (PBMC) leads to the generation of effector cells cytotoxic to bladder cancer cells in vitro. To improve BCG therapy, we previously developed human interferon (IFN)-alpha 2B secreting recombinant (r) BCG (rBCG-IFN-alpha). We demonstrated that rBCG-IFN-alpha augmented T helper type 1 (Th1) cytokine IFN-gamma production by PBMC. In this study, we further investigated whether rBCG-IFN-alpha could also enhance PBMC cytotoxicity toward bladder cancer cells.
PBMC were prepared from healthy individuals, left alone or stimulated with rBCG-IFN-alpha or control MV261 BCG, and used as effector cells in (51)Cr-release assays. Human bladder cancer cell lines T24, J82, 5637, TCCSUP, and UMUC-3 were used as target cells. To determine the role of secreted rIFN-alpha as well as endogenously expressed IFN-gamma and IL-2 in inducing the cytotoxicity, PBMC were stimulated with rBCG-IFN-alpha in the presence of neutralizing antibodies to IFN-alpha, IFN-gamma or IL-2. To determine the role of natural killer (NK) and CD8(+) T cells in inducing the cytotoxicity, both cell types were isolated after BCG stimulation of PBMC and used as effector cells in (51)Cr-release assays.
Non-stimulated PBMC showed basal levels of cytotoxicity against all target cell lines tested. MV261 BCG increased the PBMC cytotoxicity by 1.8- to 4.2-fold. rBCG-IFN-alpha further increased the PBMC cytotoxicity by up to 2-fold. Elevated production of IFN-gamma and IL-2 by PBMC was observed after rBCG-IFN-alpha stimulation. Blockage of IFN-alpha, IFN-gamma or IL-2 by neutralizing antibodies during rBCG-IFN-alpha stimulation reduced or abolished the induction of PBMC cytotoxicity. Both NK and CD8(+) T cells were found to be responsible for the enhanced PBMC cytotoxicity induced by rBCG-IFN-alpha with the former cell type being more predominant.
rBCG-IFN-alpha is an improved BCG agent that induces enhanced PBMC cytotoxicity against bladder cancer cells in vitro. This rBCG strain may serve as an alternative to BCG for the treatment of superficial bladder cancer.
Cancer Immunology and Immunotherapy 03/2009; 58(10):1647-55. · 3.70 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Interstitial cystitis (IC) is a chronic inflammatory condition of the urinary bladder with a strong autoimmune component. Currently, the major challenge in IC treatment is the development of effective therapies. RDP58 is a novel d-amino acid decapeptide with potent immunosuppressive activity. In this study, we investigated whether RDP58 was effective as an intravesical agent for treating bladder autoimmune inflammation in a transgenic mouse model (URO-OVA mice). URO-OVA mice were adoptively transferred with syngeneic activated splenocytes of OT-I mice transgenic for the OVA-specific CD8(+) TCR for cystitis induction and treated intravesically with RDP58 at days 0 and 3. Compared with controls, the RDP58-treated bladders showed markedly reduced histopathology and expressions of mRNAs and proteins of TNF-alpha, NGF and substance P. To determine whether the inhibition of bladder inflammation by RDP58 was due to the interference with effector T cells, we treated the cells with RDP58 in vitro. Cells treated with RDP58 showed reduced production of TNF-alpha and IFN-gamma as well as apoptotic death. Collectively, these results indicate that RDP58 is effective for treating T cell-mediated experimental autoimmune cystitis and may serve as a useful intravesical agent for the treatment of autoimmune-associated bladder inflammation such as IC.
Journal of Autoimmunity 07/2008; 30(4):257-65. · 7.37 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The effort to explore the specific autoimmune mechanisms of urinary bladder has long been hindered due to a lack of proper animal models. To better elucidate this issue, we developed a novel line of transgenic (Tg) mice, designated as URO-OVA mice, that express the model Ag OVA as a "self"-Ag on the bladder epithelium. URO-OVA mice are naturally tolerant to OVA and show no response to OVA stimulation. Adoptive transfer of naive OVA-specific T cells showed cell proliferation, activation, and infiltration but no bladder histopathology. In contrast, adoptive transfer of activated OVA-specific T cells induced OVA-mediated histological bladder inflammation. Increased mast cells and up-regulated mRNA expressions of TNF-alpha, nerve growth factor, and substance P precursor were also observed in the inflamed bladder. To further facilitate bladder autoimmunity study, we crossbred URO-OVA mice with OVA-specific CD8(+) TCR Tg mice (OT-I mice) to generate a dual Tg line URO-OVA/OT-I mice. The latter mice naturally acquire clonal deletion for autoreactive OT-I CD8(+) T cells (partial deletion in the thymus and severe deletion in the periphery). Despite this clonal deletion, URO-OVA/OT-I mice spontaneously develop autoimmune cystitis at 10 wk of age. Further studies demonstrated that the inflamed bladder contained infiltrating OT-I CD8(+) T cells that had escaped clonal deletion and gained effector functions before developing histological bladder inflammation. Taken together, we demonstrate for the first time that the bladder epithelium actively presents self-Ag to the immune system and induces CD8(+) T cell tolerance, activation, and autoimmune response.
The Journal of Immunology 02/2007; 178(1):539-46. · 5.79 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Previously we have reported that RT4, a well differentiated human bladder cancer line, increases the expression of macrophage derived chemokine (MDC) and interferon (IFN)-gamma-inducible protein-10 (IP-10) in response to IFN-gamma and tumor necrosis factor (TNF)-alpha. In this study we examined the signal mechanisms for inducting these 2 chemokines in RT4 cells by lipopolysaccharide (LPS), IFN-gamma and TNF-alpha.
MDC and IP-10 expression was evaluated by sandwich enzyme-linked immunosorbent assay. Signal molecule activation was examined by Western blotting and electrophoretic mobility shift assay. The expression of toll-like receptor (TLR)-4 was analyzed by reverse transcriptase-polymerase chain reaction and flow cytometry.
LPS did not induce RT4 cells to produce IP-10 and MDC. However, LPS plus IFN-gamma synergized the productions of the 2 chemokines. IFN-gamma up-regulated the expression of TLR-4, which is an LPS binding receptor. Although LPS and IFN-gamma alone marginally activated nuclear factor (NF)-kappaB but not AP-1, LPS plus IFN-gamma augmented NF-kappaB and AP-1. Specific inhibition of NF-kappaB and AP-1 pathways decreased the production of MDC and IP-10. Extracellular regulated kinase (ERK)1/2, an upstream signal of AP-1, was also responsive to LPS and/or IFN-gamma. TNF-alpha also activated NF-kappaB, AP-1 and ERK1/2. However, TNF-alpha plus IFN- gamma was associated with the activation of NF-kappaB but not of AP-1/ERK1/2 for the induction of MDC and IP-10.
IFN-gamma enhances LPS for the induction of MDC and IP-10 through up-regulation of TLR-4, and the signal pathways of NF-kappaB and AP-1/ERK1/2. This mechanism may help us understand inflammatory responses of the bladder to localized bacterial infection.
The Journal of Urology 10/2005; 174(3):1119-23. · 3.75 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Successful bacillus Calmette-Guerin (BCG) immunotherapy for bladder cancer is associated with proper induction of T helper (Th)1 immunity. Unfortunately, 30% to 40% of bladder tumors never respond to BCG. We sought evidence of antagonistic Th2 chemokine production by bladder tumors as a potential cause of BCG nonresponsiveness.
Expression of interferon-gamma inducible protein-10 (IP-10), a Th1 chemokine, and macrophage derived chemokine (MDC), a Th2 chemokine, was examined in 9 clinical bladder tumor specimens and 7 human bladder cancer lines by sandwich enzyme-linked immunosorbent assay, immunohistochemistry and immunofluorescence. Regulation of these chemokine expressions in the human RT4 bladder cancer line was also explored by reverse transcription-polymerase chain reaction and electrophoretic mobility shift assay.
Eight of 9 clinical specimens expressed IP-10 and 5 expressed MDC. However, of 7 cancer lines only 1 low grade line (RT4) expressed IP-10 and MDC, and 1 high grade line (T24) expressed IP-10. Histological staining demonstrated MDC and IP-10 expression in human bladder tumors. Interestingly interferon-gamma and tumor necrosis factor-alpha up-regulated and synergized the expression of these 2 chemokines in RT4 cells. Such positive effects appeared to be mediated by nuclear factor-kappaB but not by the AP-1 signaling pathway.
These results indicate that certain bladder tumors produce the Th2 chemokine MDC, which may antagonize the local Th1 environment induced by BCG. MDC production by bladder tumors appears to be mediated by signals distinct from those identified in macrophages.
The Journal of Urology 04/2005; 173(3):990-5. · 3.75 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Animal orthotopic tumor models are commonly used in bladder cancer studies. However, to our knowledge there is currently no accurate method to quantify tumor growth inside the bladder in living animals. We used prostate specific antigen (PSA) as a marker to cope with this limitation.
Infectious but replication incompetent retroviral particles carrying PSA coding sequence were constructed and infected into MB49 cells, a mouse bladder transitional cell carcinoma line of C57BL/6 origin. Syngeneic mice were intravesically implanted with the novel MB49-PSA transfectants. Tumor burden was evaluated by enzyme-linked immunosorbent assay measurement for PSA in urine and bladder tissues.
The MB49-PSA line actively secreted PSA in culture as well as in urine (18 to 2,062 pg/ml) depending on tumor mass. Immunofluorescence staining confirmed PSA expression in MB49-PSA derived orthotopic tumors. Urinary PSA production paralleled tumor growth and was detectable prior to the development of a palpable tumor. Although urinary PSA did not tightly correlate with tumor mass, all bladders (total of 16 tested) weighing 34 mg or greater (18 to 21 mg for age and sex matched normal bladders) showed 18 pg/ml or greater urinary PSA. In contrast, bladder tissue PSA correlated more with tumor mass in general and it was measurable even before the detection of urinary PSA. This MB49-PSA orthotopic tumor model also demonstrated its usefulness for evaluating the antibladder cancer agents gemcitabine and mitomycin.
This novel MB49-PSA line may serve as a useful tool for bladder cancer study because its growth inside the bladder can be noninvasively measured in living animals even during early stages of tumor growth.
The Journal of Urology 12/2004; 172(6 Pt 1):2414-20. · 3.75 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Mycobacterium bovis Bacillus Calmette-Guérin (BCG) use in the treatment of bladder cancer was first reported in 1976, but the mechanism of the induced antitumor activity has still not been fully explained. BCG is a potent immunostimulant, normally producing a Th1 cytokine response, including IFN. Recent studies have shown CpG oligodeoxynucleotide induce tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) expression via IFN production. Given that Mycobacterial DNA contains high amounts of CpG motifs, we hypothesized that BCG's antitumor properties are akin to CpG oligodeoxynucleotide, where the cytokine response to BCG induces TRAIL up-regulation. Using ELISA, urine IFN-gamma, and TRAIL levels were initially undetectable in BCG therapy patients but were high after later induction treatments. More importantly, patients that responded to BCG therapy had significantly higher urine TRAIL levels, which killed bladder tumor cells in vitro versus nonresponders. Flow cytometry of fresh urine revealed TRAIL-expressing neutrophils. Given these data, we propose TRAIL plays a role in BCG-induced antitumor effects.
Cancer Research 06/2004; 64(10):3386-90. · 7.86 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The antitumor activity of interleukin (IL)-12 has been demonstrated in a number of tumor models but barely tested in bladder cancer models. We evaluated the antibladder cancer activity of this cytokine in syngeneic mice bearing subcutaneous, metastatic and orthotopic tumors.
Mice were implanted subcutaneously, intravenously or orthotopically with syngeneic transitional cell carcinoma (TCC) of the bladder. The tumor bearing mice were then treated with IL-12 locally or systemically and monitored for tumor regression and survival.
In the subcutaneous model dose dependent suppression of tumorigenesis was observed when IL-12 was administered subcutaneously at a distal site with the MB49 line being more sensitive than MBT-2. IL-12 (10 days) above 50 ng daily was tumor inhibitory, while doses of 500 or 1000 ng daily prolonged survival and cured 70% and 75% of subjects, respectively. Upon re-challenge with parental tumor cells mice previously cured with IL-12 (1000 vs 500 ng daily) exhibited specific protection (70% vs 35% rejection) that was dependent on the earlier dose of cytokine. IL-12 administered intraperitoneally at a dose of 250 ng daily was more potent than subcutaneous administration and complete regression was observed. Metastatic TCC in the lungs and orthotopic tumors in the bladder also favorably responded to systemic or intravesical IL-12 therapy, respectively. Addition of IL-2 to IL-12 therapy increased tumor regression, long-term survival and rejection of re-challenged parental tumor.
IL-12 is exceptionally effective for treating murine bladder TCC in subcutaneous, metastatic and orthotopic models. The antibladder cancer activity of this cytokine should be tested in human bladder cancer therapy.
The Journal of Urology 04/2004; 171(3):1330-5. · 3.75 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Recombinant interleukin (IL)-12 and adenoviral IL-12 gene therapy have been shown to be potent therapeutic interventions for murine transitional cell carcinoma (TCC) of the bladder in vivo. We investigated the mechanisms through which IL-12 induces antibladder cancer immunity.
The ability of IL-12 to enhance interferon-gamma (IFN-gamma) expression, a major T-helper type 1 cytokine, was analyzed in murine serum, urine and splenocyte cultures. MB49, a murine TCC line, was treated with IFN-gamma and evaluated for its proliferation, surface molecule expression and sensitivity to splenocyte mediated cytotoxicity. Neutralizing antiIFN-gamma antibody was applied to test the role of IFN-gamma in the IL-12 therapy of MB49 tumor.
IL-12 was observed to significantly increase IFN-gamma concentrations in serum and urine as well as in splenocyte cultures. While IL-12 had no direct activity against TCC in vitro, IFN-gamma showed potent dose dependent antiproliferative and pro-apoptotic activity, which was further enhanced by supplementation of tumor necrosis factor-alpha. In addition, IFN-gamma substantially up-regulated the expression of surface immune molecules on TCC cells, including MHC-I, MHC-II, ICAM-I, B7.1, B7.2 and Fas. Maximum splenocyte mediated cytotoxicity against TCC was enhanced by pretreatment of target bladder cancer cells with IFN-gamma plus tumor necrosis factor-alpha. Furthermore, IL-2 in combination with IL-12 further enhanced splenocyte mediated cytotoxicity. The in vivo antibladder cancer activity of IL-12 was abolished by concurrent treatment with antibodies to IFN-gamma.
This study strongly suggests that IFN-gamma has an essential role in IL-12 induced antibladder tumor immunity. Activation of host effector immune cells by IL-12 is also required for induction of optimal tumor destruction in IL-12 therapy.
The Journal of Urology 04/2004; 171(3):1336-42. · 3.75 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Induction of a T-helper-type 1 (Th1) immune response is indispensable for successful treatment of superficial bladder cancer with BCG. In this study possible involvement of various cytokines in BCG action as well as their potential roles in enhancing and mimicking BCG effect were explored. In immunocompetent cell cultures, IFN-gamma, a major Th1 cytokine, appears to be a late responsive cytokine to BCG stimulation. Its induction requires involvement of various endogenously produced Th1 and Th2 cytokines. Functional abolishment of any one of these cytokines (IL-2, IL-6, IL-12, IL-18, GMCSF, TNF-alpha, or IFN-alpha, except IL-10) by neutralizing antibodies leads to reduced IFN-gamma production (19-82% inhibition in mouse and 44-77% inhibition in human systems, respectively). In mice cytokines IL-2, IL-12, IL-18, and GMCSF are observed to synergize with BCG for IFN-gamma production, whereas in human cytokines IL-2, IL-12, TNF-alpha, and IFN-alpha exhibit similar synergistic effects. Rational combinations of these Th1-stimulating cytokines (IL-12 plus IL-18 in mice and IL-2 plus IL-12 in humans, respectively) dramatically up-regulate IFN-gamma production that is incomparably superior to BCG for induction of this cytokine. These results suggest that combined Th1-stimulating cytokines and combinations of BCG plus selected Th1-stimulating cytokines are rational candidates for further study in the treatment of bladder cancer patients.
Cytokine 02/2003; 21(1):17-26. · 3.02 Impact Factor
