The malignant rnammary pathology can be presented like unifocal or multifocal-multicentric tumors (MFMC). The influence of this factor as prognostic is controversial. Objective: Establish if the presence of MFMC breast cancer, in comparison to the unifocal breast cancer, is associated to worse prognosis. Patients and Method: Combined prospective-retrospective cohort, corresponding to the totality of patients treated by surgery of breast cancer at Hospital FACH between 1972 and 2007 that fulfilled the inclusion criteria, obtaining a total of 589 patients. The statistic analysis was done with Kolmogorov-Smirnov tests and T-student for quantitative variables, chi square for qualitative variables and Kaplan-Meier curves with log rank test for survival. Results: The 93.4% of the patients had unifocal breast cancer, while the rest (6.6%) had MFMC cancer. There were no significant statistical differences between ages of both groups (57.88 and 54.92 years for unifocal and MFMC, respectively). MFMC cancer group presented more bilateral cancer than unifocal cancer group (7.7% versus 1.6%; p = 0.04); also, the lymph node affectation was greater in MFMC group (4.06 versus 1.83 lymph nodes; p = 0.001). There were no statistical significant differences in 5 years survival when comparing unifocal and MFMC tumors (81.8% and 90.4%, respectively; p = 0.223). There were no differences on 5 years free metástasis survival between both groups (Unifocals 86.2%; MFMC 75%; p = 0.651). Discussion: MFMC breast cancer was associated to bad prognostic factors, nevertheless, there was not significant differences in 5 years metastasis free survival and global survival between both groups, reason why multifocality-multicentricity would not confer worse prognosis to the disease.

La patología mamaria maligna puede manifestarse como tumores unifocales o multifocales-multicéntricos (MFMC). La influencia de este factor en el pronóstico es controversial. Objetivo: Establecer si la presencia de cáncer de mama MFMC se asocia a peor pronóstico. Pacientes y Método: Cohorte combinada prospectiva-retrospectiva de 589 pacientes sometidas a cirugía por cáncer de mama en el Hospital FACH entre los años 1972-2007. El análisis estadístico se realizó con las pruebas de Kolmogorov-Smirnov y T de Student para variables cuantitativas, chi cuadrado para variables cualitativas, curvas de Kaplan-Meier y test de log rank para sobrevida. Resultados: El 93,4% de las pacientes eran portadoras de cáncer unifocal, mientras el 6,6% de cáncer MFMC. No hubo diferencias estadísticamente significativas en cuanto a edad entre ambos grupos (57,88 y 54,92 años para unifocales y MFMC, respectivamente). La frecuencia de cáncer bilateral en el grupo MFMC fue mayor que en el unifocal (7,7% y 1,6%; p = 0,04); asimismo, el compromiso linfático fue mayor en este grupo (4,06 y 1,83 linfonodos comprometidos; p = 0,001). La sobrevida a 5 años fue de un 81,8% para cáncer unifocal y 90,4% para MFMC, sin diferencias estadísticamente significativas entre ambos, (p = 0,223). La sobrevida libre de metástasis a 5 años no mostró diferencias (Unifocales 86,2%; MFMC 75%; p = 0,651). Discusión: El cáncer de mama multifocal se asoció a factores de mal pronóstico; sin embargo, no se encontraron diferencias significativas en cuanto a sobrevida libre de metástasis y sobrevida global entre ambos grupos, por lo que multifocalidad-multicentricidad no conferiría un peor pronóstico a la enfermedad.

We cloned the streptokinase (STK) gene of Streptococcus equisimilis in an expression vector of Escherichia coli to overexpress the profibrinolytic protein under the control of a tac promoter. Almost all the recombinant STK was exported to the periplasmic space and recovered after gentle lysozyme digestion of induced cells. The periplasmic fraction was chromatographed on DEAE Sepharose followed by chromatography on phenyl-agarose. Active proteins eluted between 4.5 and 0% ammonium sulfate, when a linear gradient was applied. Three major STK derivatives of 47.5 kDa, 45 kDa and 32 kDa were detected by Western blot analysis with a polyclonal antibody. The 32-kDa protein formed a complex with human plasminogen but did not exhibit Glu-plasminogen activator activity, as revealed by a zymographic assay, whereas the 45-kDa protein showed a Km = 0.70 µM and kcat = 0.82 s-1, when assayed with a chromogen-coupled substrate. These results suggest that these proteins are putative fragments of STK, possibly derived from partial degradation during the export pathway or the purification steps. The 47.5-kDa band corresponded to the native STK, as revealed by peptide sequencing