Differential expression, diagnostic and prognostic significance of stathmin-1 and CD147 in various uterine smooth muscle tumors / Expresión diferencial, diagnóstico y significado de pronóstico de stathmin-1 y CD147 en diferentes tumores del músculo liso uterino

SUMMARY: Uterine smooth muscle tumors (USMT) are common, behavior-distinct gynecological tumors; including: leiomyoma (ULM), leiomyosarcoma (ULMS), and smooth muscle tumors of undetermined malignant potential (STUMP). Pre-operative distinction is difficult, thus diagnosis relies on histopathology. Immunohistochemistry (IHC) had been used to help in distinction. We studied two markers (stathmin-1 and CD147) to demonstrate whether they have diagnostic/ prognostic assist. Sixty seven USMT are studied. Age, follow up, and recurrence/metastasis data were collected. Representative slides were stained and Histologic score (HS) calculated as stain intensity (SI) X percentage of positive tumor cells (PP). Results were grouped as low expression (LE) and high expression (HE); then correlated to tumor types, and risk of recurrence/ metastasis. Statistical analysis (P < 0.05); Sensitivity, specificity, positive and negative predictive values and confidence intervals in diagnosing ULMS were calculated. Stathmin-1 HS (p= 0.000) and HE (p=0.002) were different among groups. Same as for CD147 HS and HE (both p=0.000), with a gradient increase from LM to STUMP to ULMS. Sensitivity, specificity, positive and negative predictive values and confidence intervals in diagnosing ULMS were as following: For stathmin-1 HS: 92 %; 20 %; 42 %; and 80 % (CI= 44-96 %). For Stathmin-1 HE: 80 %; 66 %; 60 %; and 84 % (CI=66-94 %). For CD147 HS: 85 %; 22 %; 41 %; and 69 %. For CD147 HE: 58 %; 49 %; 42 %; and 65 % (CI= 45-80 %), respectively. Recurrence / metastasis were documented in 6 cases (4 ULMS; 2 STUMP) with follow up ranging from 6 months to 102 months. 5 tumors had stathmin-1 HE (p=0.099); 2 had CD147 HE (p=0.393) in the primary tumors. STMN1 and CD147 are helpful diagnostic tests for USMT sub-typing, especially for ULMS. Gradient increase of expression from LM, to STUMP, to ULMS may indicate a role in malignant transformation in USMT, and in increased risk of recurrences/metastasis.

RESUMEN: Los tumores del músculo liso uterino (USMT, por sus siglas en inglés) son tumores ginecológicos comunes y de comportamiento distinto; incluyendo: leiomioma (ULM), leiomiosarcoma (ULMS) y tumores de músculo liso de potencial maligno indeterminado (STUMP). La distinción preoperatoria es difícil, por lo que el diagnóstico se basa en la histopatología. La inmunohistoquímica (IHQ) se había utilizado para ayudar en la distinción. Estudiamos dos marcadores (stathmin-1 y CD147) para demostrar si había efecto diagnóstico / pronóstico. Se estudiaron 67 USMT. Se recopilaron los datos de edad, seguimiento y recurrencia / metástasis. Las muestras representativas se tiñeron y la puntuación histológica (HS) se calculó como la intensidad de la tinción (IS) x porcentaje de células tumorales positivas (PP). Los resultados se agruparon como expresión baja (EB) y expresión alta (EA); luego se correlacionaeon con los tipos de tumores y el riesgo de recurrencia / metástasis. Análisis estadístico (P <0,05); se calcularon la sensibilidad, la especificidad, los valores predictivos positivos y negativos y los intervalos de confianza en el diagnóstico de ULMS. Stathmin-1 HS (p = 0,000) y HE (p = 0,002) fueron diferentes entre los grupos. Igual que para CD147 HS y HE (ambos p = 0,000), con un aumento de gradiente de LM a STUMP a ULMS. La sensibilidad, la especificidad, los valores predictivos positivos y negativos y los intervalos de confianza en el diagnóstico de ULMS fueron los siguientes: Para stathmin-1 HS: 92 %; 20 %; 42 %; y 80 % (IC = 44-96 %). Para Stathmin-1 HE: 80 %; 66 %; 60 %; y 84 % (IC = 66-94 %). Para CD147 HS: 85 %; 22 %; 41 %; y el 69 %. Para CD147 HE: 58 %; 49 %; 42 %; y 65 % (IC = 45-80 %), respectivamente. La recurrencia / metástasis se documentaron en 6 casos (4 ULMS; 2 STUMP) con un seguimiento que osciló entre 6 meses y 102 meses. Cinco tumores tenían stathmin-1 HE (p = 0,099); dos tenían CD147 HE (p = 0,393) en los tumores primarios. STMN1 y CD147 son pruebas de diagnóstico útiles para la subclasificación de USMT, especialmente para ULMS. El aumento en el gradiente de la expresión de LM, a STUMP, a ULMS puede indicar un papel en la transformación maligna en USMT y en un mayor riesgo de recurrencias / metástasis.

The effect of downregulation of Stathmin gene on biological behaviors of U373 and U87-MG glioblastoma cells

BACKGROUND: Stathmin as a critical protein involved in microtubule polymerization, is necessary for survival of cancer cells. However, extremely little is known about Stathmin in glioblastoma. So, this study was designed to elucidate the function of Stathmin gene in the tumorigenesis and progression of glioblastoma cells. METHOD: The lentiviral interference vector pLV3-si-Stathmin targeting Stathmin gene and the control vector pLV3-NC were established for the co-transfection of 293T cells together with the helper plasmids. Viral titer was determined via limiting dilution assay. Then pLV3-si-Stathmin and pLV3-NC were stably co-transfected into U373 and U87-MG glioblastoma cells. Expression levels of Stathmin protein in each group were determined by using Western Blot, and the proliferation and migration ability of the cells with downregulated Stathmin were evaluated through CCK8 assay and transwell invasion assay, respectively. Cell cycles and cell apoptosis were detected with flow cytometry. Finally, the effect of Stathmin in tumor formation was determined in nude mice. RESULT: DNA sequencing and viral titer assay indicated that the lentiviral interference vector was successfully established with a viral titer of 4 × 108 TU/ml. According to the results from Western Blotting, Stathmin protein expression level decreased significantly in the U373 and U87-MG cells after transfected with pLV3-si-Stathmin, respectively, compared with those transfected with pLV3-NC. In glioblastoma cells, the cell proliferation and migration were greatly inhibited after the downregulation of Stathmin protein. Flow cytometry showed that much more cells were arrested in G2/M phasein Stathmin downregulated group, compared with the non-transfection group and NC group. But Stathmin downregulation did not induce significant cell apoptosis. Tumor formation assay in nude mice showed that tumor formation was delayed after Stathmin downregulation, with a reduction in both tumor formation rate and tumor growth velocity. CONCLUSION: Stathmin downregulation affected the biological behaviors of U373 and U87-MG glioblastoma cells, inhibiting the proliferation and migration of tumor cells. Stathmin gene may serve as a potential target in gene therapy for glioblastoma.