Shiwang Li

MicroRNA-145 inhibits the growth, invasion, metastasis and angiogenesis of neuroblastoma cells through targeting hypoxia-inducible factor 2 alpha.

Recent evidence shows that hypoxia-inducible factor 2 alpha (HIF-2α) may have critical roles in the growth and progression of neuroblastoma (NB) under non-hypoxic conditions. However, the underlying mechanisms and clinical potentials of normoxic HIF-2α expression in NB still remain largely unknown. In this study, HIF-2α immunostaining was identified in 26/42 NB tissues, which was correlated with clinicopathological features. In subtotal 20 NB cases, microRNA-145 (miR-145) was downregulated and inversely correlated with HIF-2α expression. Bioinformatics analysis revealed a putative miR-145 binding site in the 3′-untranslated region (3′-UTR) of HIF-2α messenger RNA (mRNA). Overexpression or knockdown of miR-145 responsively altered both the mRNA and protein levels of HIF-2α and its downstream genes, cyclin D1, matrix metalloproteinase 14 and vascular endothelial growth factor, in normoxically cultured NB cell lines SH-SY5Y and SK-N-SH. In a luciferase reporter system, miR-145 downregulated the luciferase activity of HIF-2α 3′-UTR, and these effects were abolished by a mutation in the putative miR-145-binding site. Overexpression of miR-145 suppressed the growth, invasion, metastasis and angiogenesis of SH-SY5Y and SK-N-SH cells in vitro and in vivo, while restoration of HIF-2α expression rescued the tumor cells from miR-145-mediated defects in these biological features. Furthermore, anti-miR-145 inhibitor rescued the HIF-2α knockdown-mediated repression on the growth, migration, invasion and angiogenesis of NB cells. These data indicate that miR-145 suppresses HIF-2α expression via the binding site in the 3′-UTR under normoxic conditions, thus inhibiting the aggressiveness and angiogenesis of NB.

Expression and clinical significance of stem cell marker CD133 in human neuroblastoma

BackgroundRecent evidences indicate that CD133, a kind of transmembrane protein, can be used as a marker to isolate stem cells from tumors originating from neural crest. This study was undertaken to explore the expression and clinical significance of stem cell marker CD133 in neuroblastoma (NB).MethodsImmunohistochemical staining was used to detect the expression of CD133 in 32 patients with NB and 8 patients with ganglioneuroblastoma (GNB). The relationships were analyzed among CD133 expression, international neuroblastoma staging system (INSS) stages, pathological classification, and postoperative survival time of NB patients.ResultsThe expression rates of CD133 in NB and GNB were 46.9% (15/32) and 37.5% (3/8) respectively, mainly in cytoplasm of neuroblastoma cells. The expression rates of stage 1–2, stage 3–4 and stage 4S were 30.7%, 57.9% and 37.5%, respectively. The differences in various stages were significant (P<0.05). The positive rate of CD133 in patients with unfavorable histology (52.4%) was significantly higher than that in patients with favorable histology (36.8%) (P=0.007). The survival time of CD133 negative patients was significantly longer than that of CD133 positive patients (P=0.026).ConclusionsCD133 which might be correlated with the development and progression of NB can serve as one of the important indicators for prognosis of NB.

miRNA-558 promotes tumorigenesis and aggressiveness of neuroblastoma cells through activating the transcription of heparanase

Heparanase (HPSE) is the endogenous endoglycosidase that degrades heparan sulfate proteoglycans and promotes the tumor growth, invasion, metastasis and angiogenesis. Our previous studies have shown that HPSE is highly expressed in neuroblastoma (NB), the most common extracranial solid tumor in childhood. However, the underlying regulatory mechanisms remain largely unknown. In this study, we identified one binding site of microRNA-558 (miR-558) within the HPSE promoter. In NB tissues and cell lines, miR-558 was up-regulated and positively correlated with HPSE expression. Gain- and loss-of-function studies demonstrated that miR-558 facilitated the transcript and protein levels of HPSE and its downstream gene, vascular endothelial growth factor, in NB cell lines. In addition, miR-558 enhanced the promoter activities of HPSE, and these effects were abolished by the mutation of the miR-558-binding site. Mechanistically, miR-558 induced the enrichment of the active epigenetic marker and RNA polymerase II on the HPSE promoter in NB cells in an Argonaute 1-dependent manner, which was abolished by repressing the miR-558-promoter interaction. Knockdown of endogenous miR-558 decreased the growth, invasion, metastasis and angiogenesis of NB cells in vitro and in vivo. In contrast, over-expression of miR-558 promoted the growth, invasion, metastasis and angiogenesis of SH-SY5Y and SK-N-SH cells. Restoration of HPSE expression prevented the NB cells from changes in these biological features induced by knockdown or over-expression of miR-558. These data indicate that miR-558 induces the transcriptional activation of HPSE via the binding site within promoter, thus facilitating the tumorigenesis and aggressiveness of NB.

Laparoscopically assisted anorectal pull-through for high imperforate anus in infants: intermediate results

PURPOSE The aim of this study was to evaluate the clinical outcomes and postoperative anal function in infants with congenital high imperforate anus treated with laparoscopically assisted anorectal pull-through (LAARP). METHODS From January 2004 to July 2007, 33 patients (28 boys and 5 girls, age ranging from 3 to 10 months) with high imperforate anus underwent LAARP. Clinical data of the LAARP group were retrospectively compared with those treated by posterior sagittal anorectoplasty (PSARP; n = 28) during the same time period. Anorectal function of these patients was evaluated using the following 3 methods: the Kelly score, anorectal vector volume manometry, and magnetic resonance imaging between the ages of 3.1 and 4.4 years. RESULTS The mean operative time in LAARP and PSARP groups was 112.5 ± 12.4 and 120.4 ± 18.5 minutes (P > .05), respectively. The mean length of hospital stay in the LAARP group was shorter than that of PSARP group (11.3 ± 2.1 vs 14.6 ± 2.3 days, P < .01). No significant difference was observed between LAARP and PSARP groups regarding the Kelly score (3.52 ± 1.42 vs 3.49 ± 0.82). Although magnetic resonance imaging revealed lower malposition rates of rectum in the LAARP group than those of the PSARP group at both I-line (3.0% vs 14.3%) and M-line (3.0% vs 10.7%) levels, this was not statistically different (P > .05). Compared with the PSARP group, lower asymmetric index, larger vector volume, and higher anal canal pressure at rest and during voluntary squeeze were observed in LAARP group (P < .05). However, there were no significant differences in the length of high-pressure zone (15.2 ± 5.8 vs 15.1 ± 6.2 mm) and the presence of rectoanal relaxation reflex (84.8% vs 85.7%). CONCLUSIONS Satisfactory fecal continence can be achieved in patients with high-type imperforate anus after LAARP. Laparoscopically assisted anorectal pull-through has advantages over PSARP, including shorter hospital stay and better position of rectum. However, long-term follow-up is necessary to compare the benefits of LAARP against PSARP.

10 years of experience with laparoscopic-assisted endorectal Soave pull-through procedure for Hirschsprung's disease in China.

OBJECTIVE To report early and late results of laparoscopic-assisted endorectal Soave pull-through (LAEPT) with a short and V-shaped partial resection muscular cuff for Hirschsprungs disease (HD) over a 10-year period. METHODS The clinical courses of 218 patients who underwent modified LAEPT for HD were reviewed. LAEPT was described by the Georgeson technique. The main modifications included less dissection of the bottom of the pelvis, rectal mucosa dissection with a long cuff, coloanal anastomosis with a short cuff, and a V-shaped partial resection in the posterior wall of the muscular cuff. RESULTS From September 1999 to July 2009, 218 patients were operated on by the same surgeon. Ages ranged from 15 days to 12 years old. The aganglionic segment was located in the rectum or sigmoid colon in 176 patients, in the left colon in 38 children, and in the transverse colon in 4 patients. The median operating time was 176 minutes. Conversion to open surgery was required in 2 patients. Bleeding of the left iliac vein occurred in 1 patient, and a 180° twist of the neorectum occurred in 2 cases. Median first bowel movement time was 23 hours, and median postoperative hospital stay was 10.4 days. Median daily defecation frequency was 4.6 within 2 weeks and 2.3 at 3 months postoperatively. The immediate postoperative complications included intestine herniation from the trocar site in 2 patients, perianal excoriation in 32 patients, and anastomotic leakage in 3 patients. Follow-up ranging from 6 to 120 months was obtained for 182 patients. Late postoperative complications included postoperative adhesive bowel obstruction (1.1%), enterocolitis (7.7%), anasomostic stenosis (2.2%), constipation (1.6%), and soiling (3.6%). Eighty-seven percent had excellent and good bowel function. CONCLUSION LAEPT with a short muscular cuff with a V-shaped partial resection in the posterior wall is a safe and effective procedure for HD.

Laparoscopic extensive colectomy with transanal Soave pull-through for intestinal neuronal dysplasia in 17 children

BackgroundOpen colectomy has been preferred for intestinal neuronal dysplasia type B (IND) due to its low morbidity rate and good functional results. The aim of this study was to investigate the feasibility and results of laparoscopic colectomy with transanal Soave pull-through for the treatment of IND in children.MethodsSeventeen infants and children suffering from IND were treated by laparoscopic extensive colectomy with transanal Soave pull-through. The diagnosis of IND was made via anorectal manometry, X-ray contrast enema, suction biopsies, and laparoscopic full-thickness biopsies with hematoxylin-eosin staining. The technique used four or five abdominal ports. The sigmoid, transverse, and right colon up to the last ileal cove were mobilized laparoscopically in the extended form of IND. A modified Soave’s anastomosis was performed. The patients’ data, surgical procedures, operative data, postoperative complications and clinical outcomes were analyzed.ResultsFive patients underwent laparoscopic left colectomy with modified transanal Soave procedures, and the other 12 were treated by laparoscopic subtotal colectomy and required a Deloyers’ maneuver for the Soave pull-through. The proximal margin of barium stagnation in patients with left colectomy was restricted to the distal end of the descending colon, sigmoid colon, and that in patients with subtotal colectomy was restricted to the proximal end of the descending colon, transverse colon, hepatic flexure, and ascending colon. Postoperative complications included anastomotic leakage, severe perianal erosions, postoperative enterocolitis, and soiling. During a mean follow-up of 4 years, bowel frequency was 4–10 times per day in 3 months postoperatively in patients with subtotal colectomy. The clinical results were good, with no stool incontinence or constipation.ConclusionsLaparoscopic procedure for left colectomy and subtotal colectomy with transanal Soave pull-through in infants and children with IND is safe, feasible, and effective. The location of barium stagnation in proximal margin may be used as a method to predict initially the proximal margin of the resected bowel segment.

Clinical value of pelvic 3-dimensional magnetic resonance image reconstruction in anorectal malformations

OBJECTIVE The study aimed to build a 3-dimensional (3D) reconstruction of pelvic magnetic resonance images and evaluate the clinical value in anorectal malformations (ARMs). METHODS Magnetic resonance imaging (MRI) examinations were performed on a 1.5-T magnet. Sagittal, coronal, and transverse turbo spin-echo T1-weighted and fast spin-echo T2-weighted images of the pelvic region were obtained in 22 children. A 3D reconstruction was made on a computer and assisted by the 3D-Doctor software (Trial Version, Able Software Corp). The level and type of ARM and the developmental state of the striated muscle complex (SMC) were analyzed with 3D reconstruction image. RESULTS The 3D images of the pelvic were confirmed in 22 cases. Three-dimensional reconstructed images perfectly displayed the anatomical relationships of the SMC and the rectal atresia in these spaces. The 3D configuration of the SMC was different in each of the high- and low-type cases. The high-type malformation of SMCs differed particularly from the descriptions. CONCLUSIONS Pelvic magnetic resonance 3D reconstructed images were able to show the dimensional anatomical relations of pelvis, bladder, urethra, rectum, and SMC. Both a 3D image and positional information with MRI offers the surgeon a simulated operative profile of the SMC superior to MRI slices alone, which will help in providing morphological data for image diagnosis and operation of the ARM.

Noscapine Induced Apoptosis via Downregulation of Survivin in Human Neuroblastoma Cells Having Wild Type or Null p53

Neuroblastoma is the most common extracranial solid tumor of childhood. It accounts for 15% of pediatric cancer deaths. Chemotherapy is the mainstay of treatment in children with advanced neuroblastoma. Noscapine, a nontoxic natural compound, can trigger apoptosis in many cancer types. We now show that p53 is dispensable for Noscapine-induced cell death in neuroblastoma cell lines, proapoptotic response to this promising chemopreventive agent is mediated by suppression of survivin protein expression. The Noscapine treatment increased levels of total and Ser15-phosphorylated p53 protein in SK-SY5Y cells, but the proapoptotic response to this agent was maintained even after knockdown of the p53 protein level. Exposure of SK-SY5Y and LA1-5S cells to Noscapine resulted in a marked decrease in protein and mRNA level of survivin as early as 12 hours after treatment. Ectopic expression of survivin conferred statistically significant protection against Noscapine-mediated cytoplasmic histone-associated apoptotic DNA fragmentation. Also, the Noscapine-induced apoptosis was modestly but statistically significantly augmented by RNA interference of survivin in both cell lines. Furthermore, Noscapine-induced apoptotic cell death was associated with activation of caspase-3 and cleavage of PARP. In conclusion, the present study provides novel insight into the molecular circuitry of Noscapine-induced apoptosis to indicate suppression of survivin expression as a critical mediator of this process.

Nuss repair of pectus excavatum after surgery for congenital heart disease: Experience from a single institution

OBJECTIVE Pectus excavatum developing after surgery for congenital heart disease has its own clinical characteristics. The present study aimed to present our technique and outcomes for the Nuss procedure in the repair of these cases. METHODS We conducted a retrospective study of all patients who had not been diagnosed as pectus excavatum preoperatively but subsequently had developed pectus excavatum after surgery for congenital heart disease from February 2005 to November 2012. The Nuss procedure was applied using a series of perioperative management techniques. The data relating to the surgical technique, complications, and outcomes were analyzed. The clinical evaluation was performed using the Nuss criteria. RESULTS A total of 30 cases (14 boys and 16 girls) were included. The mean operative time was 73.5 minutes (range, 58-82). The mean length of hospital stay was 6.0 days. Complications occurred in 5 patients (16.7%), including asymptomatic pneumothorax, hematoma in the wound, pericardial penetration, and bar displacement. The mean follow-up period was 32 months (range, 9-60). Initially, 29 patients (96.7%) had excellent results, and 1 patient had a good result. The mean point of bar removal was 35.8 months (range, 30-39) after implantation. The postoperative results after bar removal in 17 patients were also recorded, including excellent results in 14 (82.4%), good results in 2 (11.7%), and a fair result in 1 patient. CONCLUSIONS The Nuss procedure has been shown to be a safe and effective approach for the repair of pectus excavatum after surgery for congenital heart disease, although dissection of substernal adhesions can increase the risk of heart injury.

Single-incision laparoscopic versus conventional laparoscopic endorectal pull-through for Hirschsprung's Disease: A comparison of short-term surgical results ☆

BACKGROUND Single-incision laparoscopy has recently become a popular procedure in pediatric surgery. The current series is the largest study to evaluate the operative complications and results of single-incision laparoscopic endorectal pull-through (SILEP) for the treatment of HD through a retrospective comparison with conventional laparoscopic endorectal pull-through (CLEP). METHODS Twenty eight patients who underwent single-incision laparoscopic endorectal pull-through for HD between July 2010 and August 2011 were compared to thirty patients who underwent CLEP. Patient age, gender, transitional zone, operative time, blood loss, intraoperative and postoperative complications, as well as short-term results, were assessed. RESULTS A total of 28 patients were included for SILEP, and historical reported 30 patients were completed by CLEP. The SILEP and CLEP groups were similar in regard to age, gender, transition zone, operative time, blood loss, hospital stay, and intraoperative complications. Postoperative results were not different, including equal daily defecation frequency and early postoperative complications. No patients with recurrent constipation were seen. Two patients with the transitional zone in the descending colon in the SILEP group had a 3mm trocar added in the left abdomen, and there were no conversions in the conventional laparoscopic group. CONCLUSION We have shown that in selected HD patients, the SILEP technique was safe and technically feasible in experienced hands. It results in similar operative results compared with conventional laparoscopic endorectal pull-through. However, the operation is more difficult if the transition zone was higher than the rectosigmoid.