RESUMO
Neuroblastoma is the second most common extracranial malignant solid tumor that occurs in childhood, and metastasis is one of the major causes of death in neuroblastoma patients. The epithelial-mesenchymal transition (EMT) is an important mechanism for both the initiation of tumor invasion and subsequent metastasis. Therefore, this study investigated the mechanism by which transforming growth factor (TGF)-ß1 induces EMT in human neuroblastoma cells. Using quantitative RT-qPCR and western blot analyses, we found that the mRNA and protein expression levels of E-cadherin were significantly decreased, whereas that of α-SMA was significantly increased after neuroblastoma cells were treated with different concentrations of TGF-ß1. A scratch test and Transwell migration assay revealed that cell migration significantly and directly correlated with the concentration of TGF-ß1 indicating that TGF-ß1 induced EMT in neuroblastoma cells and led to their migration. Inhibiting Smad2/3 expression did not affect the expression of the key molecules involved in EMT. Further investigation found that the expression of the glioblastoma transcription factor (Gli) significantly increased in TGF-ß1-stimulated neuroblastoma cells undergoing EMT, accordingly, interfering with Gli1/2 expression inhibited TGF-ß1-induced EMT in neuroblastoma cells. GANT61, which is a targeted inhibitor of Gli1 and Gli2, decreased cell viability and promoted cell apoptosis. Thus, TGF-ß1 induced EMT in neuroblastoma cells to increase their migration. Specifically, EMT induced by TGF-ß1 in neuroblastoma cells did not depend on the Smad signaling pathway, and the transcription factor Gli participated in TGF-ß1-induced EMT independent of Smad signaling.
Assuntos
Fatores de Transcrição Kruppel-Like/genética , Neuroblastoma/genética , Proteínas Nucleares/genética , Fator de Crescimento Transformador beta1/genética , Proteína GLI1 em Dedos de Zinco/genética , Actinas/genética , Antígenos CD , Apoptose/efeitos dos fármacos , Caderinas/biossíntese , Caderinas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Fatores de Transcrição Kruppel-Like/antagonistas & inibidores , Neuroblastoma/patologia , Proteínas Nucleares/antagonistas & inibidores , Piridinas/administração & dosagem , Pirimidinas/administração & dosagem , RNA Mensageiro/biossíntese , Transdução de Sinais/genética , Proteínas Smad/genética , Fator de Crescimento Transformador beta1/biossíntese , Proteína GLI1 em Dedos de Zinco/antagonistas & inibidores , Proteína Gli2 com Dedos de ZincoRESUMO
BACKGROUND: To report the preliminary experience of laparoscopic radical nephrectomy (LRN) in children with Wilms' tumor (WT) and renal cancer. PATIENTS AND METHODS: From January 2010 to October 2013, the medical records of 7 cases of WT or renal cancer in children treated by LRN at two medical centers in China were reviewed. RESULTS: All the patients were treated by LRN, and 3 of them underwent preoperative chemotherapy before surgery. The biggest tumor size was 10 cm without crossing the lateral edge of the vertebra at the time of operation. The median hospital stay was 8.5 days (range, 6-11 days). The pathologic investigation showed 5 cases of WT, 1 case of rhabdoid tumor, and 1 case of renal cell carcinoma. With a median follow-up of 1.9±1.5 years (range, 0.3-2.9 years), six children were in complete remission, and the remaining one was lost to follow-up. None of these patients presented evidence of oncological complications (tumoral recurrences, port-site implantation, or secondary lung metastases), and no small bowel obstruction occurred. CONCLUSIONS: LRN for WT and renal cancer may be considered as an option in selected children. Preoperative chemotherapy is to decrease tumor size and to facilitate the dissection, avoiding tumor rupture. For trained laparoscopic surgeons, the eventual indication of LRN is the tumor not crossing the midline. A long follow-up and more cases are necessary to evaluate the results of the laparoscopic approach.
