The low degree of effectiveness of current therapies against the bladder cancer (BC) and the progression control and malignancy of tumors in females may be related to modulation of AR (androgen) and ERS (estrogen) receptors in the mechanisms of tissue repair and ROS (reactive oxygen species). In many cancers, the interaction of AR and ERS receptors with ROS potentiates the primary lesion triggering the rapid progression and increasing the chances of malignancy of tumors. The treatment of BC with Bacillus Calmette-Guerin (BCG) has proven effective in reducing recurrence and tumor progression although there are side effects of various intensity from light irritative symptoms to severe systemic reaction. The development of various immunotherapies has become an invaluable therapeutic option. In this context, highlight the P-MAPA which for greater versatility and minimum cytotoxicity revealed through preliminary studies in vivo and in vitro opens a new perspective to combat some types of cancer including BC. The aims of this study will characterize and compare the effects of immunotherapy with BCG and P-MAPA on the steroids receptors in the BC treatment induced in rats and to establish possible action mechanisms of these immunotherapies involving cellular repair pathways, ROS and steroids receptors. For induction of urinary bladder cancer, 63 animals will be chemically induced to cancer through a dose of 1.5 mg/kg of N-methyl-N-nitrosourea (MNU) dissolved in 0.3 ml of sodium citrate (1M pH 6.0) at 15 days (weeks 0, 2, 4, 6) total of 4 doses. The other 7 animals that did not receive MNU will be considered as the Control Group (Group 1). Two weeks after the last dose of MNU, the animals will be examined by cystography to evaluate the occurrence of tumor and subsequently divided in 9 groups (7 animals per group). MNU Group (Cancer - Group 2): It will receive intravesical dose of 0.3 mL of 0.9% saline for 6 weeks, MNU + Flutamide Group (Group 3): It will receive subcutaneous injections of 10 mg / kg of Flutamide diluted in 10 ml peanut oil each 48h for 6 weeks to block androgen receptor; MNU + Tamoxifen Group (Group 4): It will receive subcutaneous injections of 1mg/kg of tamoxifen diluted in 1 ml peanut oil each 48 hours for 6 weeks to block the estrogen receptors (ER± and ER²), MNU + BCG Group (Group 5): It will receive a dose of intravesical UFC 106 - 40 mg of BCG diluted in 0.3 mL of 0.9% saline for 6 weeks consecutive, MNU + P-MAP Group (Group 6):It will receive intravesical dose of 5 mg/kg of P-MAPA dissolved in 0.3 ml of 0.9% saline for 6 weeks, MNU + BCG + Flutamide Group (Group 7) will be treated simultaneously with Flutamide and BCG in according to 3 and 5 groups, MNU +BCG + Tamoxifen Group (Group 8): It will be treated simultaneously with BCG and tamoxifen in according to groups 4 and 5, MNU + P-MAPA + Flutamide Group (Group 9): It will be treated simultaneously with P-MAPA and Flutamide in according to 3 and 6 groups; MNU + P-MAPA+ Tamoxifen Group (Group 10): It will be treated simultaneously with P-MAPA and tamoxifen groups according to 4 and 6 groups. After 16 weeks of treatment, the animals will be euthanized and the urinary bladders collected and analyzed for histopathological, immunohistochemical, Western Blotting and serum hormone and tissue levels.
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