RESUMEN
Anaplastic thyroid carcinoma (ATC) is a rare, but aggressive, carcinoma derived from follicular cells. While conventional treatments may improve patients' survival, the lethality remains high. Therefore, there is an urgent need for more effective ATC treatments. Cardiotonic steroids, such as ouabain, have been shown to have therapeutic potential in cancer treatment. Thus, we aimed to evaluate ouabain's effects in human anaplastic thyroid cells. For this, 8505C cells were cultured in the presence or absence of ouabain. Viability, cell death, cell cycle, colony formation and migratory ability were evaluated in ouabain-treated and control 8505C cells. The expression of differentiation and epithelial-to-mesenchymal transition (EMT) markers, as well as IL-6, TGFb1 and their respective receptors were also quantified in these same cells. Our results showed that ouabain in vitro decreased the number of viable 8505C cells, possibly due to an inhibition of proliferation. A reduction in migration was also observed in ouabain-treated 8505C cells. In contrast, decreased mRNA levels of PAX8 and TTF1 differentiation markers and increased levels of the N-cadherin EMT marker, as well as IL-6 and TGFb1, were found in ouabain-treated 8505C cells. In short, ouabain may have anti-proliferative and anti-migratory effect on 8505C cells, but maintains an aggressive and undifferentiated profile.
RESUMEN
Ouabain (OUA) is a glycoside shown to modulate B and T lymphocytes. Nevertheless, ouabain effects on B16F10 melanoma immune response, a mouse lineage that mimics human melanoma, are still unknown. Our aim was to study how OUA in vivo treatment modulates lymphocytes and if it improves the response against B16F10 cells. C57BL/6 mice were pre-treated with intraperitoneal (i.p) injection of OUA (0.56 mg/Kg) for three consecutive days. On the 4th day, 106 B16F10 cells or vehicle were i.p. injected. Animals were euthanized on days 4th and 21st for organs removal and subsequent lymphocyte analyses by flow cytometry. In vivo ouabain-treatment reduced regulatory T cells in the spleen in both melanoma and non-melanoma groups. Ouabain preserved the number and percentage of B lymphocytes in peripheral organs of melanoma-injected mice. Melanoma-injected mice pre-treated with OUA also survive longer. Our findings contribute to a better understanding of OUA immunological effects in a melanoma model.
Asunto(s)
Antineoplásicos/uso terapéutico , Linfocitos B/inmunología , Melanoma/tratamiento farmacológico , Ouabaína/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Linfocitos T Reguladores/inmunología , Animales , Modelos Animales de Enfermedad , Femenino , Humanos , Inmunomodulación , Inyecciones Intraperitoneales , Melanoma Experimental , Ratones , Ratones Endogámicos C57BLRESUMEN
BACKGROUND: Ouabain (OUA) is a cardiotonic glycoside originally extracted from African plants. It has also been described as an endogenous component in mammals, being released in stress situations mainly by the adrenal gland. OUA has been reported to be capable of inhibiting mitogen-induced lymphocyte proliferation and also affects B and T lymphocytes. OBJECTIVES: The aim of this work is to show the effects of OUA in peripheral T lymphocytes. METHODS: In the in vivo experiments, mice were injected intraperitoneally for 3 consecutive days with RPMI medium (control group) or 0.56 mg/kg of OUA diluted in RPMI medium (OUA group). On the fourth day, spleen or mesenteric lymph nodes were removed. RESULTS: OUA significantly reduced the number of CD4+ T lymphocytes in the spleen, especially regulatory T cells (Tregs). In vitro OUA did not inhibit the proliferation of CD4+T lymphocytes stimulated with anti-CD3 neither was able to induce the apoptosis of CD4+ nor Tregs. There was no increase in the number or percentage of T lymphocytes in the mesenteric lymph nodes, suggesting that there was no preferential accumulation of these cells in this organ. Secretion of IL-2 by activated T lymphocytes was decreased by the OUA, explaining at least in part the reduction of Tregs, since this cytokine is involved in the peripheral conversion and maintenance of Tregs. CONCLUSION: The impact of this reduction in autoimmune diseases, allergy and cancer as well as the potential use of OUA as a therapeutic approach in tumor treatment still needs more investigation.
Asunto(s)
Cardiotónicos/farmacología , Interleucina-2/metabolismo , Ouabaína/farmacología , Linfocitos T Reguladores/efectos de los fármacos , Animales , Femenino , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/inmunología , Activación de Linfocitos/efectos de los fármacos , Masculino , Ratones , Bazo/efectos de los fármacos , Bazo/inmunología , Linfocitos T Reguladores/inmunologíaRESUMEN
Ouabain (OUA) is a steroid hormone capable of inhibiting the protein Na+K+ATPase present in the plasma membrane of cells. Ouabain was initially extracted from the roots of African trees such as Acocanthera ouabaio and Strophantus gratus seeds and later described as an endogenous component found in higher mammals. The adrenal gland is the main site of synthesis of ouabain and it is released in stressful situations, conditions similar to those where there is secretion of corticosteroids. Immunological functions have been shown to be regulated by ouabain. In order to understand the effects of ouabain on B lymphocyte populations in different lymphoid organs, mice received intraperitoneal injections of ouabain for 3 consecutive days. Twenty-four hours after the last injection, cells were analyzed by flow cytometry. In the spleen, ouabain modulated especially follicular B cells, inducing a significant decrease in the percentage and absolute numbers of those cells. Ouabain also reduced the absolute number of marginal zone B lymphocytes. No difference in the percentage or absolute number of B lymphocytes in the spleen forty-eight hours after the last injection was observed. An increase in the number of B cells was seen in mesenteric lymph nodes and this retention appears to be directly related to increased expression of CXCR5 chemokine receptor and reduction of CD62L, which also explains the observed reduction of B cells in the spleen. Our results indicate that ouabain regulates the dynamics of B lymphocytes in peripheral organs but production of total IgM and IgG in the serum of animals treated in vivo with ouabain was not affected.