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ABSTRACT: In in vitro continuous culture, N (neuroblastic)-, S (substrate adherent)- and I (intermediate)-type cells were identified in human neuroblastoma (NB), where I-type is recognized as a stem cell type. Octamer-binding protein 4 (OCT4) is a cell marker used to identify the stemness of cells, whose roles in regulating I-type NB cells have yet to be fully elucidated. In the present study, we assessed the differentiation regulation role of OCT4 in BE (2)-C of I-type cells. We demonstrated that downregulation of OCT4 expression in BE (2)-C was associated with reduced cell proliferation and loss of colony formation ability on soft agar, and prompted BE (2)-C cells to differentiate to S-type cells. By contrast, overexpression of OCT4 increased cell proliferation and colony formation ratio, but no obvious differentiation promotion was observed. Furthermore, induced differentiation of BE (2)-C cells to S-type by 5-bromo-2'-deoxyuridine (BrdUrd) was accompanied by reduced expression of OCT4.
Oncology Reports 03/2013; · 1.84 Impact Factor
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ABSTRACT: Neuroblastoma (NB) is the most common extracranial solid tumor in childhood and the most frequently diagnosed neoplasm during infancy. Oct4 and Sox2 are essential transcription factors for embryonic development and play key roles in determining the fate of stem cells. In this study, we aimed to investigate the expression of Oct4 and Sox2 in NB tissues, and evaluated their relationship with various clinicopathological parameters. Oct4 and Sox2 expression in 65 samples of NB and paracancerous tissues was examined by real-time PCR. The relationship between Oct4 and Sox2 expression and clinical data was assessed. To detect Oct4 and Sox2 expression at the protein level, western blot analyses and immunohistochemical staining were employed. We found that the expression levels of Oct4 and Sox2 in NB tissues were significantly higher than those in paracancerous tissues (P<0.05). Oct4 and Sox2 expression was significantly correlated to the clinical stage of NB, but not other clinicopathological parameters including patient gender and age, tumor size, location and histological classification. In stage III and IV tumors, Oct4 and Sox2 expression was significantly decreased in the chemotherapy subgroup as compared with that of the non-chemotherapy subgroup (P<0.05). These findings suggest that the expression of Oct4 and Sox2 may correlate with the genesis and progression of NB. In addition, Oct4 and Sox2 expression can be inhibited by chemotherapy.
Oncology Reports 07/2012; 28(1):186-92. · 1.84 Impact Factor
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ABSTRACT: The purpose of the study was to sort side population (SP) cells from the neuroblastoma SK-N-SH cell line and to systematically investigate whether this population has stem cell characteristics.
Side population and non-SP cells were separated from the SK-N-SH cell line by flow cytometry, and their morphologic characteristics were analyzed by light and electron microscopy. We also used Western blotting to analyze marker proteins, Cell Counting Kit-8 assay for proliferative ability, series differentiation studies for differentiation properties, and Matrigel invasion study and tumorigenicity assay for malignant potential.
The SK-N-SH SP cells expressed high levels of stem cell markers, had high proliferative and malignant abilities, and had the capacity for rapid differentiation. The non-SP cells expressed differentiated cell marker proteins at high levels, had low proliferative and malignant abilities, and exhibited slow differentiation.
The SK-N-SH SP cells have cancer stem cell-like properties.
Journal of Pediatric Surgery 12/2010; 45(12):2305-11. · 1.45 Impact Factor
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ABSTRACT: We present 2 rare cases of lateral buttock and postanal congenital dermal sinus tract. These 2 children were noted to have a pit in the left upper lateral buttock and a postanal orifice after birth. Magnetic resonance imaging, computed tomography, and ultrasonography showed an inflammatory mass lesion in the buttock and a funicular structure adjacent to the rectum. Fistulography showed no connection between the pit and orifice. Surgical exploration revealed firm tracts from both the lateral buttock and postanus running deep to the tip of the coccyx. Histopathologic findings showed squamous cells in the walls of the sinus tracts. Our report broadens the clinical literature regarding congenital dermal sinus tract. We postulate that this disease may not always have a connection with the central nervous system, and our cases may provide examples of anal fistulas of congenital etiology in infants.
Journal of Pediatric Surgery 05/2010; 45(5):e23-5. · 1.45 Impact Factor
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ABSTRACT: Neuroblastoma (NB) is the most common pediatric extracranial cancer. Metastasis is the main cause of mortality in NB patients. Currently, little is known about the risk factors and their mechanisms that cause metastasis. Environmental endocrine disruptors (EED) are recently identified risk factors associated with various human diseases including malignant tumors. Our previous studies have implicated the role of di(2-ethylhexyl) phthalate (DEHP) and bisphenol A (BPA), two of the most common EED, in neuroblastoma cell proliferation. Here, we further investigated the effects of DEHP, BPA as well as 17beta-estradiol (E2) on the invasion and metastasis of human neuroblastoma SK-N-SH cells in vitro. SK-N-SH cells expressed estrogen receptor (ER)-beta, matrix metalloproteinases-2 (MMP-2), MMP-9 and tissue inhibitor of matrix metalloproteinase-2 (TIMP-2) at readily detectable levels. 50 microM DEHP, 0.1 microM BPA and 10 microM E2 exposure all resulted in enhanced motility and invasiveness of SK-N-SH cells (P<0.001), elevated expression of MMP-2 and MMP-9, and decreased expression of TIMP-2 (P<0.01). Furthermore, phosphorylation of Akt (Ser473) was also induced following the exposure (P<0.01). Importantly, both ER antagonist ICI182,780 and phosphoinositide 3-kinase (PI3K) specific inhibitor LY294002 significantly inhibited the DEHP, BPA, or E2-induced cell migration and invasion, as well as the disregulation of MMP-2, MMP-9 and TIMP-2 expression. ICI182,780 may have worked through abolishing Akt (Ser473) phosphorylation. In conclusion, DEHP, BPA, and E2 potently promote invasion and metastasis of neuroblastoma cells through overexpression of MMP-2 and MMP-9 as well as downregulation of TIMP-2. ER-dependent pathway and PI3K/Akt pathway are involved, which may become potential therapeutic targets for neuroblastoma treatment.
Oncology Reports 01/2010; 23(1):129-39. · 1.84 Impact Factor
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ABSTRACT: The objective of this study is to introduce a modified Soave procedure for the treatment of vascular malformations involving the anorectum and sigmoid colon (VMARS) in children.
Cases of 12 children with VMARS between 2000 and 2008 were reviewed and analyzed. The confirmed diagnosis was established by barium enema, colonoscopy, computed tomography, and magnetic resonance imaging. All the patients underwent a modified Soave procedure. In 11 patients, Sarasola-Klose hemorrhoidectomy was used for the distal part of endorectal dissection.
The mean length of resected bowel was 22.5 cm, ranging from 17 to 28 cm. Histologically, the surgical specimens showed that the lesions were venous malformation. Postoperative recovery was uneventful. The patients had good continence with no rectal bleeding, but intermittent fecal soiling was noted in one case.
VMARS forms a unique subset of patients with vascular malformations who have rectal bleeding. The combination of Soave procedure and Sarasola-Klose hemorrhoidectomy is a safe and effective procedure for VMARS.
Journal of Pediatric Surgery 12/2009; 44(12):2359-63. · 1.45 Impact Factor
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ABSTRACT: We tested the hypothesis that Wnt signaling pathways are critical to neuroblastoma development. Our objective was to explore the novel role that Wnt/beta-catenin plays in human neuroblastoma cell line SH-SY5Y, including detection of expression of wnt1 and beta-catenin in SH-SY5Y, and the morphological and proliferative changes after Wnt1 RNAi in SH-SY5Y.
PCR, Western blot and immunofluorescence technology were used to detect the expression of Wnt1 in human neuroblastoma SH-SY5Y cell line. RNAi technology was used to knock down the expression of Wnt1in SH-SY5Y. SiRNA targeting Wnt1 was transfected into SH-SY5Y cells by Lipofectamine2000. The protein expression of Wnt1 and beta-catenin were detected by Western blotting 48 h after transfection. The quantity and the morphologic changes of the cells were recorded under light microscope. The growth curve of SH-SY5Y cells after RNAi transfection was drawn through MTT assay.
Wnt1 was expressed in human neuroblastoma SH-SY5Y cells. The SH-SY5Y cell was successfully transfected with siRNA targeting Wnt1 mediated by Lipofectamine in vitro. The proteins expression of Wnt1 and beta-catenin decreased after transfection with siRNA; the numbers of the cells were decreased, accompanying abundant floating and dead cells under the light microscope. SH-SY5Y cells transfected with siRNA targeting Wnt1 showed less viability.
Wnt1 and beta-catenin expressed in SH-SY5Y cells. Knockdown of endogenous wnt1 expression could result in cell death and inhibit cell growth. From our study, we suggest that the activated embryonal development-related wnt1/beta-catenin pathway might take part in the oncogenesis and growth of neural crest-derived neuroblastoma.
Pediatric Surgery International 09/2009; 25(12):1065-71. · 1.25 Impact Factor
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ABSTRACT: To investigate the effect and mechanism of bisphenol A (BPA), one of the main environmental endocrine disruptors, on the proliferation of human neuroblastoma cells.
In vitro, cultured SK-N-SH cells were treated with 17beta-estradiol (E(2); 1 ng/mL), BPA (2 microg/mL) with or without estrogen receptor antagonist ICI182,780 (10(-6) mol/L). Viable cell number, DNA proliferation index, and expression of cyclin-dependent kinase 4 and cyclin D1 were assessed by absorbance reading, flow cytometry, and western blotting, respectively. In vivo, ovariectomized nude mice bearing SK-N-SH tumors were administered by gavage with E(2) (500 microg/kg per day, n = 11), BPA (200 mg/kg per day, n = 10), or vehicle (n = 9) for 18 days. Mice body weight, tumor volume and weight were examined every 3 days. Tumor microvessel density, proliferating cell nuclear antigen and vascular endothelial growth factor expression were evaluated by immunohistochemical staining or western blotting.
In vitro, the BPA group had 20% higher number of viable cells, 70% higher proliferation index (both P < .01), and higher expression of cyclin-dependent kinase 4 and cyclin D1 than the nontreated group. In vivo, the BPA group had over 50% higher gross tumor volume, tumor weight, microvessel density, proliferating cell nuclear antigen (P < .05 or .01), and higher vascular endothelial growth factor protein expression than the mock control group. Both in vitro and in vivo BPA effects were comparable with those by E(2). ICI182,780 effectively abolished the promoting effect for both.
Bisphenol A can promote the growth of neuroblastoma to a level similar to that of E(2). Estrogen receptor-dependent pathway and angiogenesis may contribute to the underlying mechanisms.
Journal of Pediatric Surgery 04/2009; 44(4):672-80. · 1.45 Impact Factor
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ABSTRACT: Bisphenol A (BPA), a monomer component of polycarbonate plastics and epoxy resins, is widely used in many consumer products. Zearalenone (ZEA), a non-steroidal estrogenic mycotoxin, is present in high concentrations in dairy products and cereals. Numerous researches describe a possible correlation between environmental endocrine disruptors and human tumors, but only a few papers concerned solid tumors in childhood. We investigated the effects of BPA and ZEA on the proliferation in the human neuroblastoma SK-N-SH cell line. Cell counting kit-8 and flow cytometric analysis were used to determine whether BPA and ZEA promote cell proliferation. The results indicated that BPA and ZEA-mediated increase in cell proliferation is significant (p<0.05). To explore the possible underlying mechanism, additive effect of the estrogen receptor antagonist ICI182780 or insulin-like growth factor I (IGF-I) was observed. ICI182780 could inhibit these proliferative effects of BPA and ZEA. However, no synergistic or additive growth-promoting effect was noted when IGF-1 was added. These results suggested that BPA and ZEA can promote the proliferation of SK-N-SH cells, and the estrogen receptor pathway may be involved in this effect.
Environmental Toxicology and Pharmacology 09/2007; 24(2):189-93. · 1.47 Impact Factor
