Correction to: Gene mutation spectrum and genotype-phenotype correlation in a cohort of Chinese osteogenesis imperfecta patients revealed by targeted next generation sequencing

In Table 2:Family 6 should be c.643-13_662delCTATCTTTTCTAGGGTCCCATGGGTCCCCGAGG instead of c.643-13_662delCTATCTTTTCTAGGGTCCCATGGGTCCCC.Family 33 should be c.271_279dupGCCCTCTCG instead of c.271_279dupGCCCTCT.In the 2nd para. of the Molecular diagnosis, section t(5;8)(q32;q21) should be t(5;7)(q32;q21).

Gene mutation spectrum and genotype-phenotype correlation in a cohort of Chinese osteogenesis imperfecta patients revealed by targeted next generation sequencing

The achievement of more accurate diagnosis would greatly benefit the management of patients with osteogenesis imperfecta (OI). In this study, we present the largest OI sample in China as screened by next generation sequencing. In particular, we successfully identified 81 variants, which included 45 novel variants. We further did a genotype-phenotype analysis, which helps make a better understanding of OI.

INTRODUCTION

This study aims to reveal the gene mutation spectrum and the genotype-phenotype relationship among Chinese OI patients by next generation sequencing (NGS).

METHODS

We developed a NGS-based panel for targeted sequencing of all exons of 14 genes related to OI, and performed diagnostic gene sequencing for a cohort of 103 Chinese OI patients from 101 unrelated families. Mutations identified by NGS were further confirmed by Sanger sequencing and co-segregation analysis.

RESULTS

Of the 103 patients from 101 unrelated OI families, we identified 79 mutations, including 43 novel mutations (11 frameshift, 17 missense, 5 nonsense, 9 splice site, and 1 chromosome translocation) in 90 patients (87.4%). Mutations in genes encoding type I collagen, COL1A1 (n = 37), and COL1A2 (n = 29) accounts for 73.3% of all molecularly diagnosed patients, followed by IFITM5 (n = 9, 10%), SERPINF1 (n = 4, 4.4%), WNT1 (n = 4, 4.4%), FKBP10 (n = 3, 3.3%), TMEM38B (n = 3, 3.3%), and PLOD2 (n = 1, 1.1%). This corresponds to 75 autosomal dominant inherited (AD) OI patients and 15 autosomal recessive (AR) inherited patients. Compared with AD inherited OI patients, AR inherited patients had lower bone mineral density (BMD) at spine (P = 0.05) and less frequent blue sclera (P = 0.001). Patients with type I collagen qualitative defects had lower femoral neck BMD Z-score (P = 0.034) and were shorter compared with patients with type I collagen quantitative defects (P = 0.022).

CONCLUSION

We revealed the gene mutation spectrum in Chinese OI patients, and novel mutations identified here expanded the mutation catalog and genotype and phenotype relationships among OI patients.

Enhanced Long-term and Thermal Stability of Polymer Solar Cells in Air at High Humidity with the Formation of Unusual Quantum Dot Networks

Due to the practical applications of polymer solar cells (PSCs), their stability recently has received increasing attention. Herein, a new strategy was developed to largely enhance the long-term and thermal stability of PSCs in air with a relatively high humidity of 50-60% without any encapsulation. In this strategy, semiconductor PbS/CdS core/shell quantum dots (QDs) were incorporated into the photoactive blend of poly(3-hexylthiophene) (P3HT) and phenyl-C₆₁-butyric acid methyl ester (PCBM). By replacing the initial ligands of oleic acid with halide ligands on the surface of PbS/CdS QDs via solution-phase ligand exchange, we were able to form unusual, continuous QD networks in the film of P3HT:PCBM, which effectively stabilized the photoactive layer. Air-processed PSCs based on the stabilized P3HT:PCBM film showed excellent long-term stability under high humidity, providing over 3% of power conversion efficiency (PCE) simultaneously. Around 91% of pristine PCE was retained after 30 days storage in high-humidity air without encapsulation. This constitutes a remarkable improvement compared to ∼53% retained PCE for the QD-free devices, which can be ascribed to the efficient suppression of both PCBM aggregation and oxidation of the thiophene ring in P3HT, thanks to the formation of robust QD networks. Furthermore, the presence of QD networks was able to enhance the stability of the P3HT:PCBM film against thermal stress/oxidation under high-humidity environment (50-60%) as well. The device kept 60% of pristine PCE after thermal treatment for 12 h at 85 °C in air, which is more than twice higher than that for the QD-free device. To the best of our knowledge, the work represents the first unambiguous demonstration of the formation of QD networks in the photoactive layer and of their important contribution to the stability of PSCs. This strategy is highly promising for other fullerene-based PSCs and opens a new avenue toward achieving PSCs with high PCE and excellent stability.

Association between bone mineral density, muscle strength, and vitamin D status in patients with myasthenia gravis: a cross-sectional study

Myasthenia gravis (MG) patients had low proximal hip BMD, which could be explained by reduced muscle strength, elevated bone resorption markers, vitamin D deficiency, and increased PTH levels in those with MG compared to controls.

INTRODUCTION

Muscle strength is closely correlated with bone mineral density (BMD) and vitamin D status. Here, we evaluated muscle strength, BMD, and vitamin D status in a large sample of Chinese patients with MG.

METHODS

In this cross-sectional survey, 86 patients with MG without glucocorticoid treatment and 86 healthy controls were included. Serum levels of 25-hydroxyvitamin D [25OHD], parathyroid hormone (PTH), bone turnover markers (BTMs), and BMD were measured and compared between the two groups. Grip strength and one-leg standing time (OLST) were also assessed in MG patients.

RESULTS

Low grip strength and short OLST were found in 11 (12.8%) and 12 (14.0%) MG patients, respectively. There were 3 (3.5%) MG patients with low bone mass for chronological age. Serum beta C-terminal telopeptide and PTH levels were higher (p < 0.001 and p = 0.001, respectively), and BMD at the femoral neck and trochanter were lower in MG patients (p < 0.001 and p < 0.001, respectively) compared to healthy controls. In patients with MG, grip strength was positively correlated with BMD. Serum 25OHD levels were lower in MG patients than in healthy controls (17.36 ± 6.64 vs. 22.11 ± 7.28 ng/ml, p < 0.001).

CONCLUSION

Grip strength was positively correlated with BMD in Chinese patients with MG. MG patients tended to have low proximal hip BMD, which may partially be explained by reduced muscle strength, vitamin D deficiency, increased PTH levels, and elevated bone resorption markers compared to controls.

Modeling the Blood-Brain Barrier in a 3D triple co-culture microfluidic system

The need for a blood-brain barrier (BBB) model that accurately mimics the physiological characteristics of the in-vivo situation is well-recognized by researchers in academia and industry. However, there is currently no in-vitro model allowing studies of neuronal growth and/or function influenced by factors from the blood that cross through the BBB. Therefore, we established a 3D triple co-culture microfluidic system using human umbilical vein endothelial cells (HUVEC) together with primary rat astrocytes and neurons. Immunostaining confirmed the successful triple co-culture system consisting of an intact BBB with tight intercellular junctions in the endothelial monolayer. The BBB selective permeability was determined by a fluorescent-based assay using dextrans of different molecular weights. Finally, neuron functionality was demonstrated by calcium imaging.

Abstract P1-06-07: Clinical and molecular relevance of intra-tumor genetic heterogeneity in breast cancer: Integrative analysis of data from The Cancer Genome Atlas

Background: Intra-tumor heterogeneity (ITH) plays a pivotal role in driving breast cancer progression and therapeutic resistance. Emerging evidence has indicated that the extent of genetic heterogeneity may serve as a clinically useful biomarker. While several studies have suggested the prognostic value of ITH in several cancer types, the clinical significance of genetic ITH and molecular portraits that correlated with different ITH levels were poorly understood in breast cancer. The establishment of algorithms estimating genetic ITH based on sequencing of bulk tumor DNA offered us an opportunity to explore the clinical implication of ITH in large breast cancer cohorts and, for the first time, to use integrative genomic analyses to reveal molecular portraits related to intra-tumor genetic heterogeneity.

Methods: We assessed 916 female breast cancer patients from The Cancer Genome Atlas. Mutant-allele tumor heterogeneity (MATH) values were calculated from whole-exome sequencing data. We used integers nearest to the tertiles of the MATH values as cutoff points to divide the patients into three groups nearly equal in size. The association between MATH value and clinical characteristics was evaluated, followed by survival analyses in these different MATH groups. We then compared the rates of total non-silent somatic mutations among the different MATH groups, and further determined the mutations independently associated with high MATH by logistic regression adjusting for T classification and clinical subtypes. Similar methods, superadding somatic copy number alteration (SCNA) burden in logistic model, were used to evaluate SCNA events that were significantly associated with high MATH level. Gene enrichment between the high and rest MATH groups was analyzed using Gene Set Enrichment Analysis.

Results: The patients were divided into low (MATH value lower than 33), intermediate (MATH between 33 and 46) and high (MATH higher than 46) MATH groups. High T stage, African American race, and triple-negative or basal-like subtype were associated with a higher MATH level (all P&lt;0.001). In hormone receptor-positive and human epidermal growth factor receptor-negative patients, the high MATH group showed a tendency toward a worse overall survival (P=0.052); however, while in triple-negative breast cancer, both high and low MATH indicated a worse outcome (P=0.032). Furthermore, the TP53 mutation rate increased as MATH was elevated (P&lt;0.001), whereas CDH1 mutations were correlated with a lower level of MATH (P=0.002). Several focal and arm-level SCNA events were more common in the high MATH group, including Chr8q24 with only the MYC gene in the “peak” region. Similarly, high MATH was associated with gene set enrichment related to the MYC pathway and proliferation.

Conclusion: Our study extended the knowledge concerning the clinical role of ITH in breast cancer, especially the distinct pattern of prognostic values in different clinical subtypes, which may help promote the clinical utilization of genetic ITH. Our attempt at exploring the molecular features related to ITH might provide clues for the source and consequences of ITH, inspiring subsequent experiments investigating the laws underling tumor heterogeneity.

Citation Format: Ma D, Jiang Y-Z, Liu X-Y, Liu Y-R, Yu K-D, Shao Z-M. Clinical and molecular relevance of intra-tumor genetic heterogeneity in breast cancer: Integrative analysis of data from The Cancer Genome Atlas [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-06-07.

In Vivo Ischemia Detection by Luminescent Nanothermometers

There is an urgent need to develop new diagnosis tools for real in vivo detection of first stages of ischemia for the early treatment of cardiovascular diseases and accidents. However, traditional approaches show low sensitivity and a limited penetration into tissues, so they are only applicable for the detection of surface lesions. Here, it is shown how the superior thermal sensing capabilities of near infrared-emitting quantum dots (NIR-QDs) can be efficiently used for in vivo detection of subcutaneous ischemic tissues. In particular, NIR-QDs make possible ischemia detection by high penetration transient thermometry studies in a murine ischemic hindlimb model. NIR-QDs nanothermometers are able to identify ischemic tissues by means of their faster thermal dynamics. In addition, they have shown to be capable of monitoring both the revascularization and damage recovery processes of ischemic tissues. This work demonstrates the applicability of fluorescence nanothermometry for ischemia detection and treatment, as well as a tool for early diagnosis of cardiovascular disease.

Compacting a Single Flow Diverter versus Overlapping Flow Diverters for Intracranial Aneurysms: A Computational Study

BACKGROUND AND PURPOSE

Locally compacting the mesh of a flow diverter by a dynamic push-pull technique can accelerate intracranial aneurysm healing. We asked how this deployment strategy compares with overlapping 2 flow diverters for aneurysmal flow reduction.

MATERIALS AND METHODS

Using a high-fidelity virtual stent placement method, we simulated 3 flow-diverter strategies (single noncompacted, 2 overlapped, and single compacted) in 3 aneurysms (fusiform, large saccular, and medium saccular). Computational fluid dynamics analysis provided posttreatment hemodynamic parameters, including time-averaged inflow rate, aneurysm-averaged velocity, wall shear stress, total absolute circulation, and turnover time. We examined the relationship between the achieved degree of compaction and aneurysm orifice area.

RESULTS

Flow-diverter compaction resulted in a compaction coverage of 57%, 47%, and 22% over the orifice of the fusiform, large, and medium saccular aneurysm, respectively. Compaction coverage increased linearly with orifice area. In the fusiform aneurysm, the single compacted flow diverter accomplished more aneurysmal flow reduction than the other 2 strategies, as indicated by all 5 hemodynamic parameters. In the 2 saccular aneurysms, the overlapped flow diverters achieved the most flow reduction, followed by the single compacted and the noncompacted flow diverter.

CONCLUSIONS

Compacting a single flow diverter can outperform overlapping 2 flow diverters in aneurysmal flow reduction, provided that the compaction produces a mesh denser than 2 overlapped flow diverters and this denser mesh covers a sufficient portion of the aneurysm orifice area, for which we suggest a minimum of 50%. This strategy is most effective for aneurysms with large orifices, especially fusiform aneurysms.

Structural predictions for curli amyloid fibril subunits CsgA and CsgB

CsgA are the building blocks of curli fibrils.

MR Fingerprinting of Adult Brain Tumors: Initial Experience

BACKGROUND AND PURPOSE

MR fingerprinting allows rapid simultaneous quantification of T1 and T2 relaxation times. This study assessed the utility of MR fingerprinting in differentiating common types of adult intra-axial brain tumors.

MATERIALS AND METHODS

MR fingerprinting acquisition was performed in 31 patients with untreated intra-axial brain tumors: 17 glioblastomas, 6 World Health Organization grade II lower grade gliomas, and 8 metastases. T1, T2 of the solid tumor, immediate peritumoral white matter, and contralateral white matter were summarized within each ROI. Statistical comparisons on mean, SD, skewness, and kurtosis were performed by using the univariate Wilcoxon rank sum test across various tumor types. Bonferroni correction was used to correct for multiple-comparison testing. Multivariable logistic regression analysis was performed for discrimination between glioblastomas and metastases, and area under the receiver operator curve was calculated.

RESULTS

Mean T2 values could differentiate solid tumor regions of lower grade gliomas from metastases (mean, 172 ± 53 ms, and 105 ± 27 ms, respectively; P = .004, significant after Bonferroni correction). The mean T1 of peritumoral white matter surrounding lower grade gliomas differed from peritumoral white matter around glioblastomas (mean, 1066 ± 218 ms, and 1578 ± 331 ms, respectively; P = .004, significant after Bonferroni correction). Logistic regression analysis revealed that the mean T2 of solid tumor offered the best separation between glioblastomas and metastases with an area under the curve of 0.86 (95% CI, 0.69-1.00; P < .0001).

CONCLUSIONS

MR fingerprinting allows rapid simultaneous T1 and T2 measurement in brain tumors and surrounding tissues. MR fingerprinting-based relaxometry can identify quantitative differences between solid tumor regions of lower grade gliomas and metastases and between peritumoral regions of glioblastomas and lower grade gliomas.

Advanced Fabrication of Chemically Bonded Graphene/TiO2 Continuous Fibers with Enhanced Broadband Photocatalytic Properties and Involved Mechanisms Exploration

In this article, a novel route for the synthesis of graphene/TiO₂ continuous fibers (GTF) using force-spinning combined with water vapor annealing method is reported for the first time. The morphology, structure and optical properties of the composite were fully characterized. With a single step of heat treatment process using steam at ambient conditions, we were able to initiate a series of chemical reactions, such as reduction of graphene oxide (GO), crystallization of TiO₂, formation of C-Ti bond, and introduction of oxygen vacancies into TiO₂. The incorporation of graphene in TiO₂ fibers facilitated bandgap narrowing and improved photo-induced charge separation in the photocatalyst. As a result of synergistic effects, TiO₂ fibers-2 wt% graphene (2%GTF) showed the highest photocatalytic activities in the degradation of X-3B under UV irradiation, superior to the benchmark photocatalyst P25. Under visible light irradiation, the same catalyst was about 4 times more efficient compared to pure TiO₂ fibers (PTF). A detailed study of involved active species (in particular, ·, h⁺ and ·OH) unraveled the mechanism regarding photocatalysis.

Development of an opto-electronic fiber device with multiple nano-probes

We present the fabrication and characterization of an opto-electronic fiber device which can allow for both electromechanical functionality and optical waveguiding capability. The air holes of a photonic crystal fiber are selectively sealed and then pumped with molten metal under pressure. The metal filled holes act as electrodes to which individual carbon nanotubes (CNT) are attached precisely by a laser-welding technique or a focused ion beam assisted pick-and-bond technique. The optical modal profile and the group velocity dispersion of the fabricated device are studied both numerically and experimentally. We also present preliminary experimental proof showing the feasibility of electric actuation of a pair of nanotubes by applying up to 40 V potential difference between the filled electrodes. Furthermore, numerical simulations are carried out which agree with the experimentally observed displacement of the CNT upon electric actuation. The unique aspect of our device is that it provides optical waveguiding and electromechanical nano-probing capability in a single package. Such combined functionality can potentially enable simultaneous electrical and optical manipulation and interrogation at the nanoscale.

Conditioned medium from neural stem cells inhibits glioma cell growth

Malignant glioma is one of the most common brain tumors in the central nervous system. Although the significant progress has been made in recent years, the mortality is still high and 5-year survival rate is still very low. One of the leading causes to the high mortality for glioma patients is metastasis and invasion. An efficient method to control the tumor metastasis is a promising way to treat the glioma. Previous reports indicated that neural stem cells (NSCs) were served as a delivery vector to the anti-glioma therapy. Here, we used the conditioned medium from rat NSCs (NSC-CM) to culture the human glioblastoma cell lines. We found that NSC-CM could inhibit the glioma cell growth, invasion and migration in vitro and attenuate the tumor growth in vivo. Furthermore, this anti-glioma effect was mediated by the inactivation of mitogen activated protein kinase (MAPK) pathway. Above all, this study provided the direct evidence to put forward a simple and efficient method in the inhibition of glioma cells/tumor growth, potentially advancing the anti-glioma therapy.

Clinical application of whole-genome low-coverage next-generation sequencing to detect and characterize balanced chromosomal translocations

Individuals carrying balanced translocations have a high risk of birth defects, recurrent spontaneous abortions and infertility. Thus, the detection and characterization of balanced translocations is important to reveal the genetic background of the carriers and to provide proper genetic counseling. Next-generation sequencing (NGS), which has great advantages over other methods such as karyotyping and fluorescence in situ hybridization (FISH), has been used to detect disease-associated breakpoints. Herein, to evaluate the application of this technology to detect balanced translocations in the clinic, we performed a parental study for prenatal cases with unbalanced translocations. Eight candidate families with potential balanced translocations were investigated using two strategies in parallel, low-coverage whole-genome sequencing (WGS) followed-up by Sanger sequencing and G-banding karyotype coupled with FISH. G-banding analysis revealed three balanced translocations, and FISH detected two cryptic submicroscopic balanced translocations. Consistently, WGS detected five balanced translocations and mapped all the breakpoints by Sanger sequencing. Analysis of the breakpoints revealed that six genes were disrupted in the four apparently healthy carriers. In summary, our result suggested low-coverage WGS can detect balanced translocations reliably and can map breakpoints precisely compared with conventional procedures. WGS may replace cytogenetic methods in the diagnosis of balanced translocation carriers in the clinic.

Abstract 1968: Systematic validation of microRNA based prognostic biomarkers for stage II, III and IV colorectal cancer

microRNA (miRNA) based biomarkers have great potential due to their critical regulatory functions, superior stability, and relative small number compared to mRNAs. We have previously discovered a number of miRNAs that play key roles in colon cancer stem cell resistance and demonstrated their clinical potential as prognostic biomarkers. In this study, we have validated the prognostic potential of a panel of miRNAs in 204 stage II, III, and IV colorectal cancer specimens by qRT-PCR analysis. Many of the miRNAs have been functionally validated to be important in contributing to chemoresistance to 5-FU based chemotherapy. We also determined that miR-16 is the most consistent miRNA for expression normalization. We have validated several miRNAs that are significantly associated with disease free survival (DFS) and overall survival (OS) of stage II, III and IV colorectal cancer patients. This study, together with some of the previous studies, establishes a solid foundation for miRNA based precision management of colorectal cancer.

Citation Format: Dongling Ma, Yaqi Xue, Andrew Fesler, Haiyan Zhai, Jie Yang, Apisri Ieamniramit, Wenzhe Li, Jingfang Ju. Systematic validation of microRNA based prognostic biomarkers for stage II, III and IV colorectal cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1968.

Covellite CuS nanocrystals: realizing rapid microwave-assisted synthesis in air and unravelling the disappearance of their plasmon resonance after coupling with carbon nanotubes

Semiconductor nanocrystals that show plasmonic resonance represent an emerging class of highly promising plasmonic materials with potential applications in diverse fields, such as sensing and optical and optoelectronic devices. We report a new approach to synthesizing homogeneous covellite CuS nanoplatelets in air and the almost complete disappearance of their plasmonic resonance once coupled with multiwalled carbon nanotubes (MWCNTs). These nanoplatelets were rapidly synthesized by a simple microwave-assisted approach at a relatively low reaction temperature in air, instead of under N2 as reported previously. These less severe synthesis conditions were enabled by appropriately selecting a Cu precursor and preparing a precursor sulfur solution (instead of using solid sulfur) and by using microwave radiation as the heat source. The advantages of utilizing microwave irradiation, including uniform and rapid heating, became clear after comparing the results of the synthesis with those achieved using a conventional oil-bath method under N2. The CuS nanoplatelets prepared in this way showed very strong plasmon resonance at c. 1160 nm as a result of their free charge carriers at the calculated density of nh = 1.5 × 10(22) cm(-3) based on the Drude model. With the aim of exploring their potential for near-infrared responsive optoelectronic devices, they were hybridized with functionalized MWCNTs. Their strong plasmon resonance almost completely disappeared on hybridization. Detailed investigations excluded the effect of possible structural changes in the CuS nanoplatelets during the hybridization process and a possible effect on the plasmon resonance arising from the chemical bonding of surface ligands. Charge transfer was considered to be the main reason for the almost complete disappearance of the plasmon resonance, which was further confirmed by terahertz (THz) time-domain spectrometry and THz time-resolved spectrometry measurements performed on the CuS-MWCNT nanohybrids. By extracting the rising and relaxation constants through fitting a single-exponential rising function and a bi-exponential relaxation function, in combination with the results of THz differential transmission as a function of the NIR pump fluence, it was found that hole injection changed the electronic properties of the MWCNTs only subtly on a short picosecond time scale, whereas the nature of the band structure of the MWCNTs remained largely unchanged. These findings aid our understanding of recently emerging semiconductor plasmonics and will also help in developing practical applications.

Single-agent capecitabine as maintenance therapy after induction of XELOX (or FOLFOX) in first-line treatment of metastatic colorectal cancer: randomized clinical trial of efficacy and safety

BACKGROUND

The optimal strategy of maintenance therapy for patients with mCRC is controversial. This study was to evaluate the efficacy and safety of maintenance therapy with capecitabine versus observation following inductive chemotherapy in patients with metastatic colorectal cancer.

PATIENTS AND METHODS

In this randomized, open-label, multicenter, phase III trial, patients who received 18-24 weeks of induction chemotherapy with XELOX or FOLFOX and achieved disease control were randomly assigned centrally (1:1) to receive maintenance therapy of capecitabine or only observation until disease progression. The primary end point was progression-free survival (PFS) from randomization; the secondary end points included overall survival (OS), PFS from induction treatment (PFS2) and safety. Analyses were done by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT02027363.

RESULTS

Between 30 July 2010 and 15 September 2013, 274 patients were enrolled in the study from 11 sites in China and randomly assigned to maintenance group (n = 136) or observation group (n = 138). Clinicopathological characteristics were balanced in two groups. The median follow-up time from randomization was 29.0 months [interquartile range (IQR) 21-36 months]. The primary end point of PFS was statistically significantly longer in capecitabine maintenance group than in observation group {6.43 [95% confidence interval (CI) 5.26-7.71] versus 3.43 (2.83-4.16) months, HR 0.54 (0.42-0.70), P < 0.001}. The median OS of capecitabine maintenance group was longer than that of observation group, but not statistically significant [25.63 (22.46-27.80) versus 23.30 (19.68-26.92) months; HR 0.85 (0.64-1.11), P = 0.2247]. Similar safety profiles were observed in both arms. The most common grade 3 or 4 toxicities in capecitabine maintenance group versus observation group were neutropenia, hand-foot syndrome, and mucositis.

CONCLUSIONS

Maintenance therapy with a single agent of capecitabine can be considered an appropriate option following the induction of XELOX or FOLFOX in mCRC patients with acceptable toxicities.

CLINICAL TRIALS NUMBER

NCT02027363.

Abstract P2-07-03: Nomograms to estimate long-term overall survival and breast cancer-specific survival of patients with luminal breast cancer

Purpose

Luminal breast cancer (estrogen receptor [ER] and/or progesterone receptor [PR] positive) represents approximately two-thirds of all breast cancer. This type of cancer constitutes a group of highly heterogeneous diseases with a sustained high risk of late recurrence. In this study, we aimed to develop comprehensive and practical nomograms for the first time to better estimate the long-term survival of luminal breast cancer. Thus, those patients with high risk of late recurrence and poor prognosis could be screened out and individualized treatments can be applied.

Methods

Patients with luminal breast cancer diagnosed between 1990 and 2006 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database, and randomly divided into the training (n=87,867) and validation (n=88,215) cohorts. The inclusion criteria we used to identify eligible patients were as follows: female; aged 18 to 79 years old at diagnosis; known time of diagnosis from January 1, 1990, to December 31, 2006; unilateral breast cancer; breast cancer as the first and only cancer diagnosis; diagnosis not obtained from a death certificate or autopsy; surgical treatment with either mastectomy or breast-conserving surgery; pathologic confirmation of invasive carcinoma; AJCC stages I-III; histological grade I-III and known ER and PR statuses. Patients with inflammatory breast cancer or Paget's disease and lack of data on the above inclusion criteria were also excluded. Univariate and multivariate survival analyses were applied to identify prognostic factors for overall survival (OS). The cumulative incidence function (CIF) and a competing-risks model were used to estimate the probability of breast cancer-specific survival (BCSS) and death from other causes. We integrated significant prognostic factors to build nomograms, and subjected the nomograms to bootstrap internal validation and external validation.

Results

We screened 176,082 luminal breast cancer cases. The mean age at diagnosis was 57.5 years, and mean survival time was 107.4 months. By the end of the last follow-up, 36,911 (21.0%) patients had died, including 17,855 (10.1%) died from breast cancer and 19,056 (10.8%) from other causes. The 5- and 10-year probabilities of overall death were 0.089 and 0.202, respectively. The 5- and 10-year probabilities of breast cancer specific-mortality (BCSM) were 0.053 and 0.112, respectively. Independent prognostic factors for both OS and BCSS were integrated to construct the nomograms, including age at diagnosis, race, tumor size, histology, grade, positive lymph nodes, ER/PR status and radiation. The calibration curves for the probabilities of 5- and 10-year OS and BCSS showed excellent agreement between the nomogram prediction and actual observation. The C-indexes of the nomograms were high in both internal validation (0.732 for OS and 0.800 for BCSS) and external validation (0.731 for OS and 0.794 for BCSS).

Conclusion

We established and validated nomograms that accurately predict OS and BCSS of luminal breast cancer based on a large, population-based cohort with long-term follow-up. The nomograms can identify patients with higher risk of late overall mortality and BCSM, helping physicians in facilitating individualized treatment.

Citation Format: Sun W, Jiang Y-Z, Liu Y-R, Ma D, Shao Z-M. Nomograms to estimate long-term overall survival and breast cancer-specific survival of patients with luminal breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P2-07-03.

Multiple exciton generation induced enhancement of the photoresponse of pulsed-laser-ablation synthesized single-wall-carbon-nanotube/PbS-quantum-dots nanohybrids

The pulsed laser deposition method was used to decorate appropriately single wall carbon nanotubes (SWCNTs) with PbS quantum dots (QDs), leading to the formation of a novel class of SWCNTs/PbS-QDs nanohybrids (NHs), without resorting to any ligand engineering and/or surface functionalization. The number of laser ablation pulses (N_Lp) was used to control the average size of the PbS-QDs and their coverage on the SWCNTs’ surface. Photoconductive (PC) devices fabricated from these SWCNTs/PbS-QDs NHs have shown a significantly enhanced photoresponse, which is found to be PbS-QD size dependent. Wavelength-resolved photocurrent measurements revealed a strong photoconductivity of the NHs in the UV-visible region, which is shown to be due to multiple exciton generation (MEG) in the PbS-QDs. For the 6.5 nm-diameter PbS-QDs (with a bandgap (Eg) = 0.86 eV), the MEG contribution of the NHs based PC devices was shown to lead to a normalized internal quantum efficiency in excess of 300% for photon energies ≥4.5Eg. While the lowest MEG threshold in our NHs based PC devices is found to be of ~2.5Eg, the MEG efficiency reaches values as high as 0.9 ± 0.1.

First application of the Automated QUantitative Analysis (AQUA) technique to quantify PTEN protein expression in ovarian cancer: A correlative study of NCIC CTG OV.16

BACKGROUND

Platinum resistance is a dominant cause of poor outcomes in advanced ovarian cancer (OC). A mechanism of platinum resistance is the inhibition of apoptosis through phosphatidylinositol 3 kinase (PI3K) pathway activation. The role of phosphatase and tensin homolog (PTEN), a negative regulator of this pathway, as a tumor biomarker is unclear. Quantitative analysis of PTEN expression as an alternative to immunohistochemistry has not been considered.

PATIENTS AND METHODS

In 238 patient tumors from the NCIC-CTG trial OV.16, PTEN protein expression was quantified by Automated QUantitative Analysis (AQUA). Cox model was used to study the association between PTEN expression and clinical outcomes using a minimum p-value approach in univariate analysis. Multivariate analysis was used to adjust for clinical and pathological parameters.

RESULTS

PTEN scores (range 13.9-192.3) of the 202 samples that passed quality control were analyzed. In univariate analysis, there was a trend suggesting an association between PTEN expression by AQUA as a binary variable (low ≤61 vs high >61) and progression free survival (HR=0.77, p=0.083), and in multivariate analysis, this association approached significance (HR=0.74, p=0.059). The relationship between quantitative PTEN expression and PFS differed (p=0.01 for interaction) by the extent of surgical debulking (residual disease (RD) <1cm or ≥1cm), with a numerically superior PFS in patients with high PTEN (23.5 vs 14.9m) only when RD<1cm (p=0.19). There was no association between PTEN levels and overall survival.

CONCLUSIONS

AQUA is a novel method to measure PTEN expression. Further study of PTEN as a biomarker in OC is warranted.

An optimized microRNA signature algorithm to predict clear cell renal cell carcinoma metastasis: A 265-case validation study using paraffin specimens

612

Background: Clear cell renal cell carcinoma (ccRCC) metastasis is associated with a dismal prognosis. Early identification of patients at high or low risk of metastasis may help to guide appropriate treatment. There are currently no reliable clinico-pathologic and laboratory modalities for this purpose in a routine clinical setting. We previously performed a microarray study using frozen ccRCC specimens and identified dysregulation of 4 microRNAs (miRNAs), miR-10b, miR-139-5p, miR-130b and miR-199b-5p, to be highly associated ccRCC metastasis and prognosis. Methods: We established a training cohort including formalin-fixed paraffin-embedded (FFPE) specimens of localized (n = 13; pT1) and metastatic (n = 15; M1) ccRCCs. We measured the expression of the 4 miRNAs of the training cohort samples by quantitative RT-PCR, normalized with miR-24, one of the most stably expressed miRNAs in human renal tissue as we previously reported. Using the risk score method, we rebuilt a mathematical formula with cutoff points to predict a patient to be at high, low or equivocal risk of metastasis. We validated the signature in an FFPE test cohort of 265-case primary ccRCCs. We examined the signature performance and its correlation with the cancer-specific survival. Results: Multivariate logistic regression analysis showed the signature to be highly associated with ccRCC metastasis (OR 7.67, 95%Cl 2.80-21.09, p < 0.0001), with the overall sensitivity and specificity of 80% and 76%. The sensitivities and specificities were 72% and 78%, 70% and 67%, and 78% and 75% for stage I, II or III patients, respectively. The signature predicted metastasis of small ccRCCs ( ≤ 4.0 cm), with the sensitivity of 60% and specificity of 77%. The overall positive and negative predictive values (PPV and NPV) were 61% and 89%. The area under the curve of ROC was 0.8. The signature was also found to be well correlated with worse cancer-specific survival (HR 3.06, 95%Cl 1.49-6.93, p < 0.01). Conclusions: This optimized miRNA signature can reliably predict ccRCC metastasis and prognosis and may help to stratify patients for more appropriate therapies and suitable clinical trials.

Outcome of patients with relapsed diffuse large B-cell lymphoma who fail second-line salvage regimens in the International CORAL study

Salvage chemotherapy followed by autologous stem cell transplantation (ASCT) is the standard second-line treatment for relapsed and refractory diffuse large B-cell lymphoma (DLBCL). However, the strategy is less clear in patients who require third-line treatment. Updated outcomes of 203 patients who could not proceed to scheduled ASCT in the Collaborative Trial in Relapsed Aggressive Lymphoma (CORAL) are herein reviewed. In the intent-to-treat analysis, overall response rate to third-line chemotherapy was 39%, with 27% CR or CR unconfirmed, and 12% PR. Among the 203 patients, 64 (31.5%) were eventually transplanted (ASCT 56, allogeneic SCT 8). Median overall survival (OS) of the entire population was 4.4 months. OS was significantly improved in patients with lower tertiary International Prognostic Index (IPI), patients responding to third-line treatment and patients transplanted with a 1-year OS of 41.6% compared with 16.3% for the not transplanted (P<0.0001). In multivariate analysis, IPI at relapse (hazard ratio (HR) 2.409) and transplantation (HR 0.375) independently predicted OS. Third-line salvage chemotherapy can lead to response followed by transplantation and long-term survival in DLBCL patients. However, improvement of salvage efficacy is an urgent need with new drugs.

Role of necroptosis in the pathogenesis of solid organ injury

Necroptosis is a type of regulated cell death dependent on the activity of receptor-interacting serine/threonine-protein (RIP) kinases. However, unlike apoptosis, it is caspase independent. Increasing evidence has implicated necroptosis in the pathogenesis of disease, including ischemic injury, neurodegeneration, viral infection and many others. Key players of the necroptosis signalling pathway are now widely recognized as therapeutic targets. Necrostatins may be developed as potent inhibitors of necroptosis, targeting the activity of RIPK1. Necrostatin-1, the first generation of necrostatins, has been shown to confer potent protective effects in different animal models. This review will summarize novel insights into the involvement of necroptosis in specific injury of different organs, and the therapeutic platform that it provides for treatment.

Facile and Mild Strategy to Construct Mesoporous CeO2-CuO Nanorods with Enhanced Catalytic Activity toward CO Oxidation

CeO2-CuO nanorods with mesoporous structure were synthesized by a facile and mild strategy, which involves an interfacial reaction between Ce2(SO4)3 precursor and NaOH ethanol solution at room temperature to obtain mesoporous CeO2 nanorods, followed by a solvothermal treatment of as-prepared CeO2 and Cu(CH3COO)2. Upon solvothermal treatment, CuO species is highly dispersed onto the CeO2 nanorod surface to form CeO2-CuO composites, which still maintain the mesoporous feature. A preliminary CO catalytic oxidation study demonstrated that the CeO2-CuO samples exhibited strikingly high catalytic activity, and a high CO conversion rate was observed without obvious loss in activity even after thermal treatment at a high temperature of 500 °C. Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and hydrogen temperature-programmed reduction (H2-TPR) analysis revealed that there is a strong interaction between CeO2 and CuO. Moreover, it was found that the introduction of CuO species into CeO2 generates oxygen vacancies, which is highly likely to be responsible for high catalytic activity toward CO oxidation of the mesoporous CeO2-CuO nanorods.