INVESTIGADORES
CHULUYAN Hector Eduardo
congresos y reuniones científicas
Título:
SLPI (Secretory leukocyte protease inhibitor) induces apoptosis on mammary tumor cells.
Autor/es:
26. AMIANO, NICOLÁS; COSTA, JULIETA; ROMEO, DOLORES; ORQUEDA, ANDRÉS; SILVIA ESTEIN; CHULUYAN, EDUARDO
Lugar:
Buenos Aires
Reunión:
Congreso; First French-Argentine Immunology Congress; 2010
Institución organizadora:
SAI
Resumen:
SLPI is an 11.7 kDa protein, characterized as an anti-inflammatoryagent. It has been described that SLPI is expressed in severaltumor cell lines. However, the role of SLPI in cancer is not completelyelucidated. Previously studies in our laboratory showedthat SLPI over-expressing cells do not develop tumor in mice.The aim of this work was to analyze the ability of SLPI to induceapoptosis of mammary tumor cells. Apoptosis was studyon murine F3II cell line (mammary carcinoma) and 2C1 (F3II derivedcells over-expressing SLPI). Apoptosis of 2C1 and F3II cellswas measured by flow cytometry with FITC-Annexin V Kit andmicroscopy by ethidium bromide/acridine orange staining. Theapoptosis of 2C1 cells was significantly higher than F3II controlcells (45 ± 5% vs 16 ± 3%, p<0.01). Furthermore, 2C1 cells weremuch more sensitive to apoptosis induced by serum deprivation(83 ± 4% vs 23 ± 3%, p<0.005) and increased 18-fold caspase 3 activity compared to F3II cells. When F3II cells, culturedwith or without serum, were treated with exogenous rhSLPI (4μg/ml, 48h), apoptosis was increased (Basal: 16 ± 3%, SLPI: 21 ±4%, p<0.05; Basal without serum: 23±2%, SLPI without serum:34±2%, p<0.05). Also, an increase (3.5-fold) in caspase-3 activitywas observed in cells culture without serum in the presence ofexogenous rhSLPI. Similar results were obtained, when a mammaryhuman tumor cell line (MCF-7) was treated with rhSLPI.Remarkably, treatment of 2C1 cells with SLPI siRNA or blockingSLPI mAb partially reversed the cell apoptosis (25 ± 3 and 13 ± 1% of inhibition, respectively). These data demonstrate that SLPIis a pro-apoptotic factor, at least for mammary tumor cells examined.Furthermore, these results suggest that the apoptoticactivity of SLPI on mammary tumor cells may be involved in thelack of growth of 2C1 cells in vivo, previously described in ourlaboratory.