combination of propranolol and heated 4t1 cells elicits beneficial response against mouse model of breast cancer

Background: induction of th1 responses against tumor antigens may be a useful strategy to control malignancy. in this respect, previous studies have shown that beta-adrenoreceptor antagonists can promote cellular immune responses. objectives: this survey was done to evaluate the beneficiary of a new immunotherapy method against breast cancer made by mixing heated 4t1 cells and propranolol, as an adjuvant. methods: subcutaneously injected live 4t1 cells (1 × 10^4) were used to induce breast cancer in six to eight-week-old female balb/c mice. when all mice had a palpable tumor, immunotherapy was dawned. mice in the treatment groups were vaccinated, twice at a one-week interval, with the extract of heated 4t1(1 × 10^5) either alone or in combination with propranolol (6 mg/kg). negative control mice received phosphate-buffered saline (pbs) as the same schedule. one-half of the mice were euthanized one week after the last vaccination to investigate the immune response profile. other animals were kept until death occurred spontaneously. results: combined immunotherapy with propranolol and extract of heated 4t1 had synergistic effects, causing a more desirable survival curve and slower tumor growth when compared to other tumor-bearing mice receiving only heated 4t1 or pbs. furthermore, combined immunotherapy significantly augmented the production of ifn-γ nitric oxide production, respiratory burst, and cytotoxicity of natural killer cells in the splenocyte culture of tumor-bearing mice. conversely, combined immunotherapy significantly regressed the production of tgf-β and il-10 in the splenocyte population compared to cytokine production by splenocytes from other groups. conclusions: combined heated 4t1 cells with propranolol promote beneficial outcomes in the animal model of breast cancer.