The present study describes the histopathological and molecular effects of P-MAPA (Protein aggregate magnesium-ammonium phospholinoleate-palmitoleate anhydride) intravesical immunotherapy combined with systemic doxorubicin or cisplatin for treatment of non-muscle invasive bladder cancer (NMIBC) in an appropriate animal model. Our results showed an undifferentiated tumor, characterizing a tumor invading mucosa or submucosa of the bladder wall (pT1) and papillary carcinoma in situ (pTa) in the Cancer group. The histopathological changes were similar between the combined treatment with intravesical P-MAPA plus systemic Cisplatin and P-MAPA immunotherapy alone, showing decrease of urothelial neoplastic lesions progression and histopathological recovery in 80% of the animals. The animals treated systemically with cisplatin or doxorubicin singly, showed 100% of malignant lesions in the urinary bladder. Furthemore, the combined treatment with P-MAPA and Doxorubicin showed no decrease of urothelial neoplastic lesions progression and histopathological recovery. Furthermore, Akt, PI3K, NF-kB and VEGF protein levels were significantly lower in intravesical P-MAPA plus systemic cisplatin and in intravesical P-MAPA alone treatments than other groups. In contrast, PTEN protein levels were significantly higher in intravesical P-MAPA plus systemic cisplatin and in intravesical P-MAPA alone treatments. Thus, it could be concluded that combination of intravesical P-MAPA immunotherapy and systemic cisplatin in the NMIBC animal model was effective, well tolerated and showed no apparent signs of antagonism between the drugs. In addition, intravesical P-MAPA immunotherapy may be considered as a valuable option for treatment of BCG unresponsive patients that unmet the criteria for early cystectomy.

This study reports the effects of a promising therapeutic option for non-muscle invasive bladder cancer (NMIBC) based on OncoTherad intravesical immunotherapy in an appropriated animal model. OncoTherad is a nanostructured inorganic phosphate complex associated to glycosidic protein, which exhibits immunomodulatory and antitumor properties. Biochemical parameters in rats, mice and rabbits treated intravesically with OncoTherad at doses of 20-100 mg/kg, did not differed statistically from their respective controls, exhibiting no systemic toxic effects. All the target organs did not present inflammation and histopathological changes. NMIBC was induced by treating female Fischer 344 rats with N-methyl-N-nitrosourea (MNU). Bacillus Calmette-Guérin (BCG) were used as positive control in the animal models. The results demonstrated that animals treated with OncoTherad distinctly showed a significant histopathological recovery from the cancer state of animals (80%) when compared to BCG treatment. In addition, BCG and OncoTherad intravesical immunotherapies were able to restore TLR2 levels. However, OncoTherad increased of TLR4 levels when compared to BCG. Thus, the activation of TLR4 by Oncotherad was efficient in reducing urothelial neoplastic progression. All data are indicative that of OncoTherad is a feasible candidate for the NMIBC treatment.

e16004 Background: The new modalities for treating patients with non-muscle invasive bladder cancer (NMIBC) for whom Bacillus Calmette-Guerin (BCG) has failed or is contraindicated are recently increasing due to the development of new drugs. In this scenario, a new perspective is represented by OncoTherad immunomodulator. OncoTherad is a nanostructured inorganic phosphate complex associated to glycosidic protein, developed by University of Campinas/ Brazil, which exhibits antitumor properties. This study detailed and characterized the therapeutic effects of OncoTherad based on activation of Toll-Like Receptors (TLRs) signaling pathways and regulation of receptor activator of nuclear factor kβ (RANK)/RANK ligand (RANKL) cytokine system in an animal model of NMIBC, as well as, compared these effects with BCG treatment. Methods: Fisher 344 female rats were submitted to NMIBC induction with N-methyl-N-nitrosourea (MNU). MNU treated animals were further divided into 3 groups (10 animals per group): the NMIBC group received 0.30 mL of saline solution; the NMIBC-BCG group received of 2 mg/mL of BCG; the NMIBC-OncoTherad group received 20 mg/Kg dose of OncoTherad. All animals were treated intravesically every other week for 6 weeks. Results: Our results demonstrated that OncoTherad intravesical immunotherapy led to distinct activation of TLRs 2 and 4-mediated innate immune system, resulting in increased interferons signaling pathway, which was more effective (80.0%) in the NMIBC treatment, when compared to BCG treatment (20.0%). Interferon signaling pathway activation induced by OncoTherad led to increase of iNOS expression, resulting in apoptosis and histopathological recovery. Also, OncoTherad immunotherapy decreased RANK/RANKL expression, resulting in reduced regulatory T (Treg) cells. Conclusions: The decreased of RANK/RANKL expression by OncoTherad was fundamental to up-regulation interferon signaling pathway and in suppresion of abnormal cell proliferation. Thus, OncoTherad immunotherapy could be considered an important therapeutic strategy for NMIBC, as well as, opens a new perspective for treatment of BCG-refractory or relapsed patients.

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461 Background: Effective intravesical therapies remain lacking for non-muscle invasive bladder cancer (NMIBC) when Bacillus Calmette-Guerin fails. OncoTherad is a nanostructured inorganic phosphate complex associated with glycosidic protein, developed by the University of Campinas/Brazil, which triggers immunomodulatory and antitumor activities. Previous studies have shown that Platelet Rich Plasma (PRP) acts on immune activation and exerts antitumor effects. This study characterized the effects of the OncoTherad associated with PRP in the treatment of NMIBC chemically induced in mice and the modulation promoted in the Toll-like receptors (TLRs) signaling pathway. Methods: Forty-two C57BL/6J mice were divided into groups: Control; Cancer (N-ethyl-N-nitrosourea carcinogen, 50 mg/ml); PRP (0.1 ml); OncoTherad (20 mg/ml); OncoTherad+PRP 10 mg/ml and OncoTherad+PRP 20 mg/ml. The intravesical doses (0.1 ml) were instilled once a week for 6 weeks after induction. Results: The NMIBC induction decreases (p<0.05) body weight, although after treatments the body weight was recovered similarly to the healthy mice. The treatments did not significantly alter the biochemical patterns of the urine and food and water consumption. There was no acute toxicity or kidney damage, and the presence of hydroureter was variable. The urinary bladders of mice treated with Oncotherad associated or not with PRP showed hyperemia associated with the inflammatory condition. The thickening of the urinary bladder wall in the Cancer group was more evident than in the treated groups, in which there were bladders without thickening or macroscopic lesions. Flat carcinoma in situ (pTis) was present in 100% of the mice in the Cancer group and the intensity of immunoreactivities for TLR2, IL-6, TLR4, and IRF-3 was significantly weaker in comparison with the Control, indicating suppression of the immune system in the tumor microenvironment. When treated intravesically with PRP only, mice showed 28.6% of tumor progression inhibition rate; with OncoTherad 85.7% and with OncoTherad+PRP 10 mg/ml or 20 mg/ml 71.4%. Intravesical treatments led to distinct activation of TLRs 2 and 4-mediated innate immune system in the interleukins (MyD88-dependent) and interferons (TRIF-dependent) signaling pathways. The combined treatment of OncoTherad+PRP increased (p<0.05) the percentage of positive TLR4 urothelial cells and the intensity of immunoreaction for TLR4 compared to the isolated treatments and the immunoreactivities of NF-kB, IL-6, TLR4, IRF-3, and IFN-γ in comparison to the Cancer. Conclusions: Intravesical treatment with OncoTherad plus PRP promoted significant inhibition of tumor progression, possibly due to immunomodulatory activity involving the TLR pathway. This association can constitute a therapeutic strategy for refractory NMIBC patients.