Correction to: Metabolic relevance for N-hydroxy L-arginine reduction in estrogen-negative breast cancer cells.

We found a unit error with our LC-MS lower limit of quantitation (LLOQ) measurement in the Amino Acids Journal.

Metabolic relevance for N-hydroxy L-arginine reduction in estrogen-negative breast cancer cells.

We had shown Nw-hydroxy-L-arginine (NOHA) as a promising blood-based biomarker for estrogen-receptor-negative (ER-) breast cancer (BC) that differentiates ER- BC based on grade and molecular phenotype. In this in vitro study, we assessed the metabolic relevance for ER- BC-specific NOHA modulation and correlated them with NOHA regulatory responses. This study aids future NOHA clinical utility in ER- BC diagnosis and therapy management and would prove useful for potential drug discovery and development process.

The NIH NeuroBioBank: creating opportunities for human brain research.

The National Institutes of Health (NIH) NeuroBioBank is a federally funded research resource for human neurologic diseases and disorders. This chapter will discuss the principles that guided the creation of the NIH NeuroBioBank and the rationale for the resource model selected. In addition, we will describe some performance metrics in the first 2 years and highlight recent advances in biomedical neuroscience that could only have been achieved using postmortem human tissues. The NIH NeuroBioBank was created in order to increase availability of high-quality postmortem human brain tissues to the research community across a broad spectrum of neurologic diseases and disorders, and to achieve economies of scale over previous funding and organizational models. In addition, we aim to increase public awareness about the value of human tissue donation for research by providing web-based information to the public and through active outreach to disease advocacy communities. Studies with human brain tissue have led to a rapid increase in our knowledge of the biologic differences between humans and are bridging the divide between humans and model organisms. Studies of human brain are beginning to give us a glimpse not only into what makes us uniquely human as well as how individual biology may be connected to health and disease.

Assessing N w-hydroxy-L-arginine applicability as a novel ethnic specific estrogen-negative breast cancer marker.

In our prior study we identified N w-hydroxy-L-arginine (NOHA) as a simple, yet sensitive indicator for estrogen negative (ER-) breast cancer early-prognosis, but not estrogen positive (ER+), and to offer ethnic selectivity for ER- detection. However, the ability of NOHA to assess ER- breast tumor based on disease progression, and tumor severity needs further delineation. Also, the overall NOHA storage stability needs to be validated. To assess the NOHA predictive capability based on disease progression, ER-/ER+ 3D-spheroids (from breast tumor cell lines of human origin) were cultured for 10 weeks. We found only ER- 3D-spheroid cultured for 10 weeks to show a gradual reduction in NOHA (both in culture medium and 3D-spheroid lysates) that correlated with a progressive increase in cellular NOS2 expression and NOS2 activity (measured as total nitrites). We additionally identified the NOHA-NOS2 correlation to be ethnically selective between ER- African American versus ER- Caucasian groups. Interestingly, such NOHA reduction was observed earlier in ER- culture medium (viz., after week 1) than from ER- 3D-spheroids lysates (viz., at the end of 3 weeks). When categorized based on 3D-spheroid grade, we found a ≥ 68% NOHA reduction in ER- spheroids that were ≤ 3 weeks old, that was categorized as "low-grade" (based on tumor size ≤ 250 µm, and with cellular characteristics identical to healthy cells). A substantial reduction in NOHA of ≥ 87% occurred with ER- 3D-spheroids grown for 6 weeks, which were categorized as "intermediate-grade" (with tumor size of ≥ 400 µm, and with less characteristic similarity to control spheroids). These in vitro findings thus suggest a distinct correlation between NOHA reduction and ER- tumor grade. Such distinctive correlation between NOHA and ER- tumor grade was additionally observed in de-identified clinical samples where a onefold higher reduction in NOHA occurred in grade-2 than with grade-1 de-identified patient plasma (when compared with control), and such correlation offered ethnic selectivity between ER- African American and ER- Caucasian groups. Of additional interest, when NOHA overall storage stability was assessed by incubating patient plasma and culture medium spiked with 75 pg/ml NOHA at multiple incubation temperatures and time-points, we found NOHA to maintain its stability for up to 6 weeks in culture medium and for 7 days in plasma at 4 °C and below. These results thus provide the first evidence of NOHA as a stable indicator to monitor ER- disease progression and tumor severity in ethnically distinctive populations.

Rigidity and flexibility in the tetrasaccharide linker of proteoglycans from atomic-resolution molecular simulation.

Proteoglycans (PGs) are covalent conjugates between protein and carbohydrate (glycosaminoglycans). Certain classes of glycosaminoglycans such as chondroitin sulfate/dermatan sulfate and heparan sulfate utilize a specific tetrasaccharide linker for attachment to the protein component: GlcAß1-3Galß1-3Galß1-4Xylß1-O-Ser. Toward understanding the conformational preferences of this linker, the present work used all-atom explicit-solvent molecular dynamics (MD) simulations combined with Adaptive Biasing Force (ABF) sampling to determine high-resolution, high-precision conformational free energy maps ΔG(φ, ψ) for each glycosidic linkage between constituent disaccharides, including the variant where GlcA is substituted with IdoA. These linkages are characterized by single, predominant (> 97% occupancy), and broad (45° × 60° for ΔG(φ, ψ) < 1 kcal/mol) free-energy minima, while the Xyl-Ser linkage has two such minima similar in free-energy, and additional flexibility from the Ser sidechain dihedral. Conformational analysis of microsecond-scale standard MD on the complete tetrasaccharide-O-Ser conjugate is consistent with ABF data, suggesting (φ, ψ) probabilities are independent of the linker context, and that the tetrasaccharide acts as a relatively rigid unit whereas significant conformational heterogeneity exists with respect to rotation about bonds connecting Xyl to Ser. © 2017 Wiley Periodicals, Inc.

Does preoperative neutrophil lymphocyte ratio predict risk of recurrence and occult central nodal metastasis in papillary thyroid carcinoma?

BACKGROUND: Preoperative neutrophil to lymphocyte ratio (NLR) might be prognostic in papillary thyroid carcinoma (PTC). Given the controversy of prophylactic central neck dissection (pCND) in clinically nodal-negative (cN0) PTC, our study evaluated whether preoperative NLR predicted disease-free survival (DFS) and occult central nodal metastasis (CNM) in cN0 PTC. METHODS: A total of 191 patients who underwent pCND were analyzed. Complete blood counts with differential counts were taken before operation. NLR was calculated by dividing preoperative neutrophil count with lymphocyte count. Patients were categorized into NLR tertiles: first (NLR < 1.93; n = 63), second (NLR = 1.93-2.79; n = 64), and third tertile (NLR > 2.79; n = 64). Four other patient types, namely, benign nodular goiter, clinically nodal-positive (cN1) PTC, poorly differentiated thyroid carcinoma, and anaplastic thyroid carcinoma (ATC), were used as references. RESULTS: Age at operation (p < 0.001) and tumor size (p = 0.037) significantly increased with higher NLR. First tertile had significantly more TNM stage I tumors (p = 0.01) and lowest MACIS score (p = 0.002). Tumor size [hazard ratio (HR) 1.422, 95% confidence interval (CI) 1.119-1.809, p = 0.004] and multicentricity (HR = 2.545, 95% CI 1.073-6.024, p = 0.034) independently predicted DFS, whereas old age [odds ratio (OR) 1.026, 95% CI 1.006-1.046, p = 0.009), male (OR 2.882, 95% CI 1.348-6.172, p = 0.006), and large tumor (OR 1.567, 95% CI 1.209-2.032, p = 0.001) independently predicted occult CNM. NLR was not significantly associated with DFS or occult CNM. ATC had significantly higher NLR than cN1 PTC (7.28 vs. 2.74, p < 0.001). CONCLUSIONS: Although a higher NLR may imply a poorer tumor profile, it was not significantly associated with a worse DFS or higher risk of occult CNM in cN0 PTC. Perhaps, future research should focus on the prognostic value in other thyroid cancer types with a poorer prognosis.

Evaluating the morbidity and efficacy of reoperative surgery in the central compartment for persistent/recurrent papillary thyroid carcinoma.

BACKGROUND: Although reoperative surgery in the central compartment (RCND) is indicated for bulky or progressive persistent/recurrent papillary thyroid carcinoma (PTC), its associated morbidity and disease outcomes remain unclear. We evaluated RCND outcomes by comparing them with those of patients who underwent primary central neck dissection (CND). METHODS: After matching for age, sex, tumor size, and initial tumor stage, the morbidity and outcomes of 50 consecutive patients who underwent RCND were compared with data from 75 patients who underwent primary therapeutic CND during the same period. Matching was performed blind to the morbidity and disease outcome of each patient. A stimulated thyroglobulin (sTg) <2 ng/ml was considered undetectable. RESULTS: Relative to primary CND, the incidence of extranodal extension (p = 0.010) and size of metastatic lymph nodes (p < 0.001) were significantly greater in the RCND group. Postoperative hypoparathyroidism and vocal cord palsy rates were comparable in the groups. There were two esophageal injuries in the RCND group and none in the primary CND group. The secondary CND group achieved a significantly lower undetectable postablation sTg rate (12.0 vs. 52.0 %, p = 0.001) and worse 10-year disease-free survival (35.6 vs. 91.8 %, p = 0.001) and cancer-specific survival (82.0 vs. 98.5 %, p = 0.001) than the primary CND group. CONCLUSIONS: Although RCND for persistent/recurrent PTC was performed with morbidity comparable to that seen with primary CND, it was associated with some serious complications. Short- and long-term disease control appeared moderate with approximately one-tenth of patients having an undetectable sTg level 6 months after ablation and one-third remaining clinically disease-free after 10 years.

Robot-assisted whipple's operation for solid pseudopapillary tumour of pancreas.

Solid pseudopapillary tumor is a rare tumor of the pancreas. They are slow growing with low malignant potential. The prognosis is excellent after surgical resection. Here we report a case of solid pseudopapillary tumor of the pancreas at the uncinate process. There are increasing interests about minimal access surgery for pancreatic lesion. However conventional laparoscopic Whipple's operation is technically difficult. With the benign characteristic of this tumor, as well as the advance in robotic surgery, robot assisted approach is an ideal alternative for this case. The operation was performed with a five-port approach with the use of da Vinci S Surgical System (Intuitive Surgical Inc., Sunnyvale, CA, USA). The operative time was 420 min and operative blood loss was 100 ml. The post operative course was uneventful and the patient was discharged on post operative day 10. This case demonstrates the feasibility of robot assisted Whipple's operation, which has not been extensively reported in the literature.

Bevacizumab-induced tumor vessel remodeling in rhabdomyosarcoma xenografts increases the effectiveness of adjuvant ionizing radiation.

PURPOSE: Inhibition of vascular endothelial growth factor (VEGF) may effect transient "normalization" of tumor vasculature by pruning immature vessels, resulting in improved tumor perfusion and oxygenation. This may improve the efficacy of adjuvant ionizing radiation (IR). We tested this hypothesis using bevacizumab, an anti-VEGF antibody, in rhabdomyosarcoma (RMS) xenografts. METHODS: Mice bearing orthotopic alveolar RMS xenografts were treated with a single dose of bevacizumab, IR, or a combination of the two on different schedules. Tumors were then evaluated for changes in microvessel density, vessel maturity, vessel permeability, intratumoral oxygenation, as well as altered growth. RESULTS: After bevacizumab treatment, a significant decrease in tumor microvessel density and a significant increase in tumor vessel maturity, defined as the ratio of pericytes to endothelial cells, were observed, suggesting pruning of immature vessels lacking pericytes. Tumor vessel permeability was also significantly decreased and intratumoral oxygen tension increased 2 and 5 days after bevacizumab owing to a transient improvement in tumor perfusion. Treatment with IR 2 or 5 days after bevacizumab resulted in the greatest antitumor activity. CONCLUSION: Our findings support the hypothesis that VEGF inhibition with bevacizumab transiently normalizes the dysfunctional vasculature of RMS xenografts, improving tumor oxygenation and increasing tumor sensitivity to adjuvant IR.

Bevacizumab suppresses neuroblastoma progression in the setting of minimal disease.

BACKGROUND: We hypothesized that vascular endothelial growth factor (VEGF) contributes to autocrine stimulation of neuroblastoma and that inhibition of its signaling pathway contributes to the anticancer activity of bevacizumab, an anti-VEGF monoclonal antibody. METHODS: For in vitro studies, 2 neuroblastoma cell lines, CHLA-255 and NB1691, were treated with VEGF+/-bevacizumab. For in vivo studies, disseminated neuroblastoma was established by intravenous administration of luciferase-expressing tumor cells in SCID mice prior to bevacizumab treatment. RESULTS: Exogenous VEGF increased cell counts after 48 h (NB1691: 58,878 +/- 8279 vs 137,500 +/- 13,108 cells, P < .001; CHLA: 1.56 x 10(6) +/- 866 vs 1.81 x 10(6) +/- 2550 cells, P <.001); the addition of bevacizumab abrogated this stimulation. In vivo, mice with disseminated disease treated twice weekly with intraperitoneal bevacizumab had a decreased tumor burden at day 14 and prolonged survival (NB1691: 50 +/- 2 vs 43 +/- 2 days, P < .001; CHLA: 53 +/- 3 vs 42 +/- 1 days, P = .006). Interestingly, VEGF and basic fibroblast growth factor expression was increased in treated NB1691 tumors, which likely occurred in response to VEGF signaling inhibition. CONCLUSION: Our results suggest that VEGF has a role in neuroblastoma autocrine signaling. Maintenance therapy with bevacizumab may be useful for disease suppression after maximal cytoreductive therapy; however, upregulation of proangiogenic factors may provide resistance to this approach, which suggests that maximal antitumor efficacy may require combination therapy.

Bortezomib inhibits angiogenesis and reduces tumor burden in a murine model of neuroblastoma.

BACKGROUND: Bortezomib is a proteasome inhibitor with pleiotropic antitumor activity. Here we investigate the antiangiogenic and antitumor efficacy of bortezomib against neuroblastoma both in vitro and in a murine model of localized and disseminated disease. METHODS: In vitro activity of bortezomib was assessed by evaluating its effect on cell proliferation and cell cycle status. Localized tumor burden was followed with caliper measurements and total-body bioluminescence in mice with disseminated disease. The antiangiogenic activity was evaluated with immunohistochemistry and human vascular endothelial growth factor (VEGF) enzyme-linked immunosorbent assay on tumor protein extracts. RESULTS: Bortezomib treatment resulted in dose and time-dependent decreases in cell proliferation and resulted in cell cycle arrest. In vivo, bortezomib restricted tumor growth in a model of localized disease and decreased bioluminescence in mice with disseminated disease. That decreased bioluminescence reflected decreased tumor burden was confirmed at necropsy by assessing disease in specific organs. In addition, treatment resulted in a decrease in intratumoral vessel counts and reduced tumor VEGF expression. CONCLUSION: Bortezomib shows significant activity against neuroblastoma in vitro, and it inhibits tumor growth and angiogenesis in vivo. These results suggest that clinical studies of bortezomib are warranted for the treatment of this difficult disease.