Expression Of The Stem Cell Transcription Factors C-My、Sox2、Oct4and Klf4in Children With Neuroblastoma And Its Significance

TO objective: Neuroblastoma (NB) is the most common extracranial solidtumor in childhood. It is a kind of embryonic development of tumor, derivedfrom embryonic neural crest sympathetic neurons or sacral parasympatheticneurons. Due to the high degree of malignancy and easy early metastasis, it’susually diagnosed at advance stage. Methods of treatment include surgery,radiotherapy and chemotherapy, in which chemotherapy is the primary treatment.During the treatment, chemotherapy resistance and recurrence are the urgentsolved problems. At the same time, the side effects of chemotherapy cause thesecondary damage to children’s body. Therefore, for a long time, the effect ofthe therapy is not good enough and the prognosis is poor. With the furtherresearch of cancer, the concept of tumor stem cells,(TSCs) was proposed, andthe TSCs plays an important role in the progression, metastasis, chemotherapyresistance and recurrence of malignant tumors. Its characteristics determine thesensitivity of tumor treatment and the outcome. The further study of TSCs maylay the foundation for development of more effective cancer diagnosis andtreatment methods. C-My, sox2, oct4and klf4, as embryonic transcriptionalregulation genes of stem cells, are important factors for regulating embryonicdevelopment. During the early course of embryogenesis, the four factors are thekey regulators in maintaining embryonic pluripotency and self-renewal capacity,and for maintaining the characteristics of tumor stem cells, they are also veryimportant. Therefore, we try to study expression of the stem cell transcriptionfactor C-My, Sox2, Oct4and Klf4in children NB tissues and the expression of the correlation between the four factors. Analyze the relationship between thefour factors and the clinical course, pathological type, and explore the role of thefour factors in the development process of neuroblastoma, to provide moreeffective diagnosis and treatment measures for the NB. Especially for theadvanced stage NB children.We hope our experiment can offer new treatmentgene targets, especially, for the advanced stage NB children.Methods: The subjects came from The Pediatrics of The Fourth Hospital ofHebei Medical University, confirmed by pathological diagnosis from January2007to June2013.A total of33cases of surgical resection or biopsy specimenswere classified into experimental group. According to the internationalneuroblastoma staging system(INSS),the cases were divided into Ⅲ stage groupwith10cases and Ⅳstage group with23cases; According to the pathologicaltype, the cases were divided into neuroblastoma group with24cases andganglioneuroblastoma group with9cases; And the cases were divided intowithout chemotherapy before surgical operation group with13cases and withchemotherapy before surgical operation group with20cases. Another10cases ofresidual normal adrenal gland specimens, which were from the patient withsevere hydronephrosis and received surgical resection, were used as controlgroup. Immunohistochemical S-P method was employed to detect the expressionof c-Myc, klf4, oct4and sox2.Meanwhile; the data were analyzed with SPSS17.0software to explore the relevance of the expression and the clinical phases,pathological type and chemotherapy before surgical operation.Results:1The expression of c-Myc in NB tissuesC-Myc was expressed in20.00%cases of the control group and78.79%cases of NB group, the difference had statistical significance（x2=12.381；P=0.00）;it was expressed in40.00%cases of and73.91%cases of NB Ⅳ stage,the difference had no statistical significance（P=0.114）; it was expressed in 40.44%cases of ganglioneuroblastoma and100%cases of neuroblastoma, thedifference had statistical significance（P=0.01）; it was expressed in61.54%cases of the group with chemotherapy before surgery and100%cases of thegroup without chemotherapy before surgury,the difference had statisticalsignificance（P=0.005）;it’s expression in the NB tissues had no correlation withgender（P=0.125）and age(P=0.346).2The expression of sox2in NB tissuesSox2was expressed in20.00%cases of the control group and63.63%casesof NB group, the difference had statistical significance（x2=4.251;P=0.039）;itwas expressed in70.00%cases of and91.30%cases of NB Ⅳ stage, thedifference had no statistical significance（P=0.114）; it was expressed in44.44%cases of ganglioneuroblastoma and70.8%cases of neuroblastoma,the differencehad no statistical significance（P=0.23）; it was expressed in30.77%cases of thegroup with chemotherapy before surgery and85.00%cases of the group withoutchemotherapy before surgury,the difference had statistical significance（P=0.03）;it’s expression in the NB tissues had no correlation with gender（P=0.274）and age(P=0.3).3The expression of oct4in NB tissuesOct4was expressed in30.00%cases of the control group and72.73%casesof NB group, the difference had statistical significance（x2=4.307；P=0.038）;itwas expressed in50.00%cases of and82.61%cases of NB Ⅳ stage, thedifference had no statistical significance（P=0.4）; it was expressed in33.33%cases of ganglioneuroblastoma and87.50%cases of neuroblastoma,thedifference had statistical significance（P=0.005）; it was expressed in38.46%cases of the group with chemotherapy before surgery and95.00%cases of thegroup without chemotherapy before surgury,the difference had statisticalsignificance（P=0.01）;it’s expression in the NB tissues had no correlation with gender（P=0.230）and age(P=0.458).4The expression of klf4in NB tissuesKlf4was expressed in90.00%cases of the control group and30.30%casesof NB group, the difference had statistical significanc（ex2=8.81；P=0.03）;it wasexpressed in40.00%cases of and26.09%cases of NB Ⅳ stage, the differencehad no statistical significance（P=0.09）; it was expressed in66.67%cases ofganglioneuroblastoma and16.67%cases of neuroblastoma,the difference hadstatistical significance（P=0.005）; it was expressed in69.23%cases of the groupwith chemotherapy before surgery and0.05%cases of the group withoutchemotherapy before surgury,the difference had statistical significance（P=0.00）;it’s expression in the NB tissues had no correlation with gender（P=0.433）and age(P=1.00).5Spearman rank correlation analysis showed that：The expression of c-Myc and sox2in children NB tissues was positivelycorrelated（rs=0.394，P=0.023）;the expression of c-Myc and oct4in childrenNB tissues was positively correlated（rs=0.556，P=0.01）; the expression ofc-Myc and klf4in children NB tissues was negatively correlated（rs=-0.586，P=0.000）; the expression of sox2and oct4in children NB tissues was positivelycorrelated（rs=0.567，P=0.01）; the expression of sox2and klf4in children NBtissues was negatively correlated（rs=-0.585，P=0.000）；the expression of oct4and klf4in children NB tissues was negatively correlated（rs=-0.630，P=0.000）.TO conclusions:1The expression of c-Myc,sox2and oct4were significantly higher in the childrenNB tissues than the normal control tissues, whereas the expression lf klf4wassignificantly lower, so we speculate that c-Myc,sox2,oct4and klf4mayparticipate in the occurrence process of NB.2The expression of c-Myc and oct4in the ganglioneuroblastoma tissues were lower than the neuroblastoma tissues, and the expression of klf4in theganglioneuroblastoma tissues were higher than the neuroblastoma tissues, whichsuggested that the three factors may had relationship with the differentiation ofthe children NB tissues and may become the prognostic indicators.3The expression of c-Myc, oct4and sox2in the without chemotherapy beforesurgical operation group were significantly higher than their expression in thegroup.with chemotherapy before surgical operation. In contrast, the expression ofklf4in the group without chemotherapy before surgical operation weresignificantly lower than their expression in the group with chemotherapy beforesurgical operation. The results suggested that chemotherapy drugs can influencethe expression of the four factors, and we speculated that the four factors maycorrelate with the working mechanism of the chemotherapy drugs and reflect theeffect of chemotherapy. They are expected to become the new targets for thetreatment of NB.4The correlations between c-Myc and sox2, c-Myc and oct4, oct4and sox2inchildren NB tissues were all positively correlated, which suggested that the threefactors had synergistic effect in the development and progression of NB. Thecorrelations between c-Myc and klf4,sox2and klf4,oct4and klf4in children NBtissues were all negatively correlated, which suggested that klf4and the threefactors had antagonism effect in the development and progression of NB.5The expression of c-Myc,sox2,oct4and klf4in children NB tissues had no relat-ionship with age, gender and clinical stages(Ⅲ or Ⅳ stage).