Mary Beth Madonna

Closing arguments for gastroschisis: management with silo reduction.

Abstract Background: There are two approaches to close gastroschisis. Primary closure (PC) is reduction and fascial closure; silo closure (SC) places viscera in a preformed-silo and reduces the contents over time. We have shifted from PC to SC. This study compared the outcomes of these two techniques. Methods: Records of babies with gastroschisis from 1994–2004 were reviewed. Closure type, ventilator days, days to full-feeds, hospital days, complications, and mortality were recorded. Results: Twenty-eight patients underwent PC; 20 patients had SC. Differences in ventilator days, days to full-feeds, and hospital days were not statistically significant. Nine PC patients developed closure-related complications vs. none in SC (P<0.05). Eight PC vs. two SC patients had non-closure-related complications (P<0.05). Four PC vs. zero SC patients developed necrotizing enterocolitis (P<0.05). Five PC vs. one SC patients had ventral hernia (P<0.05). No patient died. Conclusion: PC resulted in higher incidence of reclosure, non-closure-related complications, and necrotizing enterocolitis. Consequently, we recommend SC as the preferred treatment.

Effect of resident postgraduate year on outcomes after laparoscopic appendectomy for appendicitis in children.

PURPOSE The purpose of this study was to determine if the postgraduate level of resident in the operating room correlates with outcomes for pediatric patients undergoing laparoscopic appendectomy. SUBJECTS AND METHODS The charts of all children who underwent laparoscopic appendectomy for appendicitis from 2007 to 2011 at a free-standing childrens hospital were reviewed. Outcomes of interest were compared between patient groups based on postgraduate level of the junior-most surgeon in the operating room: (1) junior resident (postgraduate year [PGY]-1, -2, and -3); (2) senior resident (PGY-4 or -5); (3) fellow (PGY-6 or -7); or (4) attending surgeon only. RESULTS Junior resident (n=327), senior resident (n=129), fellow (n=246), and attending (n=73) groups were similar in terms of age (P=.69), gender distribution (P=.51), race (P=.08), and perforation status (P=.30). Operative time was shorter for senior residents (P=.002), fellows (P<.001), and attending surgeons operating without a resident (P<.001) compared with cases with junior residents. The rate of conversion to an open operation was similar among groups (P=.46). Resident level was not predictive of complications, which occurred in 26 junior resident cases (8.0%; referent), 17 senior resident cases (13.2%; odds ratio [OR] 1.73; P=.11), 33 fellow cases (13.4%; OR 1.71; P=.06), and 8 attending cases (11.0%; OR 1.62; P=.27). Fellow involvement was associated with an increased rate of postoperative percutaneous abscess drainage or re-operation for abscess or bowel obstruction (9.8%; OR 2.31; P=.020). CONCLUSIONS Involvement of junior residents in pediatric laparoscopic appendectomy is associated with increased operative time but no higher rate of complications.

To drain or not to drain: A single institution experience with neonatal intestinal perforation

Abstract Aims: The optimal surgical treatment for extremely-low-birth-weight (ELBW) neonates with pneumoperitoneum is controversial. This study aimed to identify clinical factors associated with two known causes of pneumoperitoneum-necrotizing enterocolitis (NEC) and spontaneous intestinal perforation (SIP), and assesses the treatment outcome with primary peritoneal drainage (PPD) vs. laparotomy. Methods: We reviewed and analyzed clinical characteristics and outcome from records of neonates with pneumoperitoneum treated at our institution from January 1999 to January 2003. Results: Forty-six neonates (31 NEC, 15 SIP) were treated with either PPD (20 with NEC, 13 with SIP) or laparotomy (11 with NEC, 2 with SIP). In neonates who underwent PPD, those with NEC (vs. SIP) were less likely to have a patent ductus arteriosus, but were more likely to have been fed, have drains placed later in life, have a subsequent laparotomy, a longer total parental nutrition course, a higher 30-day mortality, and to take more days to begin enteral feeds. Conclusion: The etiology of pneumoperitoneum (NEC vs. SIP) in ELBW neonates can usually be determined preoperatively. Neonates with SIP should have a drain placed while those with NEC should undergo laparotomy.

Presence of Germ Cells in Disorders of Sex Development: Implications for Fertility Potential and Preservation

Purpose: We sought to determine the presence of germ cells in the gonads of patients with disorders of sex development to establish whether preservation of germ cells for future fertility potential is possible. We hypothesized that germ cells are present but vary by age and diagnosis. Materials and Methods: We reviewed histology from patients with disorders of sex development who underwent gonadectomy/biopsy from 2002 to 2014 at a single institution for pathological classification of the gonad, composition of gonadal stroma and germ cell presence. Results: A total of 44 patients were identified and germ cells were present in 68%. The presence and average number of germ cells per mm2 were analyzed by gonad type and diagnosis. By gonad type all ovotestes, most testes, ovaries and dysgenetic testes, and 15% of streak gonads had germ cells present. By diagnosis germ cells were present in all patients with complete androgen insensitivity syndrome, Denys‐Drash syndrome, SRY mutation, mixed gonadal dysgenesis, ovotesticular conditions and StAR (steroid acute regulatory protein) deficiency, in some patients with persistent müllerian duct syndrome, XO/XY Turner syndrome and disorders of sex development not otherwise specified, and in none with complete or partial gonadal dysgenesis. Germ cells were present in the gonads of 88% of patients 0 to 3 years old, 50% of those 4 to 11 years old and 43% of those older than 12 years. Conclusions: Germ cells were present in the majority of our cohort and the presence decreased with age. This novel, fertility driven evaluation of germ cell quantity in a variety of disorders of sex development suggests that fertility potential may be greater than previously thought. Further studies must be done to evaluate a larger population and examine germ cell quality to determine the viability of these germ cells.

Differential effect of long-term drug selection with doxorubicin and vorinostat on neuroblastoma cells with cancer stem cell characteristics

Numerous studies have confirmed that cancer stem cells (CSCs) are more resistant to chemotherapy; however, there is a paucity of data exploring the effect of long-term drug treatment on the CSC sub-population. The purpose of this study was to investigate whether long-term doxorubicin treatment could expand the neuroblastoma cells with CSC characteristics and histone acetylation could affect stemness gene expression during the development of drug resistance. Using n-myc amplified SK-N-Be(2)C and non-n-myc amplified SK-N-SH human neuroblastoma cells, our laboratory generated doxorubicin-resistant cell lines in parallel over 1 year; one cell line intermittently treated with the histone deacetylase inhibitor (HDACi) vorinostat and the other without exposure to HDACi. Cells’ sensitivity to chemotherapeutic drugs, the ability to form tumorspheres, and capacity for in vitro invasion were examined. Cell-surface markers and side populations (SPs) were analyzed using flow cytometry. Differentially expressed stemness genes were identified through whole genome analysis and confirmed with real-time PCR. Our results indicated that vorinostat increased the sensitivity of only SK-N-Be(2)C-resistant cells to chemotherapy, made cells lose the ability to form tumorspheres, and reduced in vitro invasion and the SP percentage. CD133 was not enriched in doxorubicin-resistant or vorinostat-treated doxorubicin-resistant cells. Nine stemness-linked genes (ABCB1, ABCC4, LMO2, SOX2, ERCC5, S100A10, IGFBP3, TCF3, and VIM) were downregulated in vorinostat-treated doxorubicin-resistant SK-N-Be(2)C cells relative to doxorubicin-resistant cells. A sub-population of cells with CSC characteristics is enriched during prolonged drug selection of n-myc amplified SK-N-Be(2)C neuroblastoma cells. Vorinostat treatment affects the reversal of drug resistance in SK-N-Be(2)C cells and may be associated with downregulation of stemness gene expression. This work may be valuable for clinicians to design treatment protocols specific for different neuroblastoma patients.

The Effect of Vorinostat on the Development of Resistance to Doxorubicin in Neuroblastoma

Histone deacetylase (HDAC) inhibitors, especially vorinostat, are currently under investigation as potential adjuncts in the treatment of neuroblastoma. The effect of vorinostat co-treatment on the development of resistance to other chemotherapeutic agents is unknown. In the present study, we treated two human neuroblastoma cell lines [SK-N-SH and SK-N-Be(2)C] with progressively increasing doses of doxorubicin under two conditions: with and without vorinsotat co-therapy. The resultant doxorubicin-resistant (DoxR) and vorinostat-treated doxorubicin resistant (DoxR-v) cells were equally resistant to doxorubicin despite significantly lower P-glycoprotein expression in the DoxR-v cells. Whole genome analysis was performed using the Ilumina Human HT-12 v4 Expression Beadchip to identify genes with differential expression unique to the DoxR-v cells. We uncovered a number of genes whose differential expression in the DoxR-v cells might contribute to their resistant phenotype, including hypoxia inducible factor-2. Finally, we used Gene Ontology to categorize the biological functions of the differentially expressed genes unique to the DoxR-v cells and found that genes involved in cellular metabolism were especially affected.

The role of nerve growth factor in caspase-dependent apoptosis in human BE(2)C neuroblastoma

PURPOSE The purpose of the study was to determine if nerve growth factor (NGF) stimulation induces apoptosis in the BE(2)C neuroblastoma cell line in vitro. METHODS The LPCX retroviral vector was used to achieve stable transduction of NGF complementary DNA into BE(2)C neuroblastoma cells. Wild-type and NGF-transduced cells were then incubated with varying concentrations of NGF for varying periods. A laddering assay was performed to determine the presence of DNA fragments characteristic of apoptosis. The expression of various cleaved and total caspases was determined by Western immunoblotting. RESULTS p75 receptor expression in the NGF-transduced cell line was equivalent to that in the wild-type cell line, but Trk A receptor expression was significantly decreased in BE(2)C-NGF cells. DNA laddering assay demonstrated that only BE(2)C-NGF cells underwent apoptosis after stimulation with exogenous NGF. BE(2)C-NGF cells have increased expression of cleaved caspase-3 when compared with wild-type cells. Cleaved caspase-3 expression is further increased with exogenous NGF stimulation in the transduced cells. CONCLUSION This study confirms that NGF stimulation of BE(2)C neuroblastoma cells can induce apoptosis through activation of the caspase cascade in vitro. The differential expression of the receptors Trk A and p75 between the wild-type and NGF-transduced cell lines may explain the differing effects observed.

Treatment of neuroblastoma in congenital central hypoventilation syndrome with a PHOX2B polyalanine repeat expansion mutation: New twist on a neurocristopathy syndrome

Neuroblastoma in patients with congenital central hypoventilation syndrome (CCHS) as part of a neurocristopathy syndrome is a rare finding and has only been associated with paired‐like homeobox 2b (PHOX2B) non‐polyalanine‐repeat‐expansion mutations. To the best of our knowledge, we report the first case of a child with CCHS and Hirschsprung disease who had a PHOX2B polyalanine‐repeat‐expansion mutation (PARM) (genotype 20/33) and developed high‐risk neuroblastoma. We further describe his treatment including chemotherapy and therapeutic I131‐metaiodobenzylguanidine. This case highlights the need to consider neuroblastoma in patients with CCHS and the longest PHOX2B PARMs and to individualize treatment based on co‐morbidities. Pediatr Blood Cancer

Efficacy of class I and II vs class III histone deacetylase inhibitors in neuroblastoma

BACKGROUND Histone deacetylase (HDAC) inhibitors have shown promise in the treatment of resistant and refractory tumors including neuroblastoma. The goal of the study was to compare the efficacy of a class III HDAC inhibitor (cambinol) to a class I and II inhibitor (vorinostat). METHODS In vitro efficacy of vorinostat and cambinol, alone or in combination with doxorubicin, was assessed by 2-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide calorimetric assay using both wild-type (WT) and doxorubicin-resistant (DoxR) SK-N-SH neuroblastoma cells. In vivo efficacy was determined using the same drug combinations in nude mice bearing xenograft implants of WT and DoxR cells on opposite flanks. RESULTS Vorinostat and cambinol were efficacious against WT and DoxR neuroblastoma cells in vitro. In WT cells, the potency of the doxorubicin itself overshadowed any effect of cotherapy with vorinostat or cambinol. The effect of vorinostat and/or cambinol on the DoxR cells was constant across progressively increasing doses of doxorubicin. In the in vivo model, the efficacy of doxorubicin itself (88% reduction in tumor volume) again overshadowed any effect of cotreatment with vorinostat or cambinol on the WT tumors. However, in the DoxR tumors, doxorubicin alone had no efficacy, but cotreatment with either cambinol or vorinostat suppressed tumor growth (70% and 91% reduction in tumor volume, respectively). CONCLUSIONS Both the class III HDAC inhibitor cambinol and the class I/II HDAC inhibitor vorinostat have efficacy against SK-N-SH neuroblastoma cells, including those resistant to doxorubicin.

Midkine Mediates Intercellular Crosstalk between Drug-Resistant and Drug-Sensitive Neuroblastoma Cells In Vitro and In Vivo

Resistance to cytotoxic agents has long been known to be a major limitation in the treatment of human cancers. Although many mechanisms of drug resistance have been identified, chemotherapies targeting known mechanisms have failed to lead to effective reversal of drug resistance, suggesting that alternative mechanisms remain undiscovered. Previous work identified midkine (MK) as a novel putative survival molecule responsible for cytoprotective signaling between drug-resistant and drug-sensitive neuroblastoma, osteosarcoma and breast carcinoma cells in vitro. In the present study, we provide further in vitro and in vivo studies supporting the role of MK in neuroblastoma cytoprotection. MK overexpressing wild type neuroblastoma cells exhibit a cytoprotective effect on wild type cells when grown in a co-culture system, similar to that seen with doxorubicin resistant cells. siRNA knockdown of MK expression in doxorubicin resistant neuroblastoma and osteosarcoma cells ameliorates this protective effect. Overexpression of MK in wild type neuroblastoma cells leads to acquired drug resistance to doxorubicin and to the related drug etoposide. Mouse studies injecting various ratios of doxorubicin resistant or MK transfected cells with GFP transfected wild type cells confirm this cytoprotective effect in vivo. These findings provide additional evidence for the existence of intercellular cytoprotective signals mediated by MK which contribute to chemotherapy resistance in neuroblastoma.