Expanded base editing in rice and wheat using a Cas9-adenosine deaminase fusion

Nucleotide base editors in plants have been limited to conversion of cytosine to thymine. Here, we describe a new plant adenine base editor based on an evolved tRNA adenosine deaminase fused to the nickase CRISPR/Cas9, enabling A•T to G•C conversion at frequencies up to 7.5% in protoplasts and 59.1% in regenerated rice and wheat plants. An endogenous gene is also successfully modified through introducing a gain-of-function point mutation to directly produce an herbicide-tolerant rice plant. With this new adenine base editing system, it is now possible to precisely edit all base pairs, thus expanding the toolset for precise editing in plants.

Hallucinating Face Image by Regularization Models in High-Resolution Feature Space

In this paper, we propose two novel regularization models in patch-wise and pixel-wise respectively, which are efficient to reconstruct high-resolution (HR) face image from low-resolution (LR) input. Unlike the conventional patch-based models which depend on the assumption of local geometry consistency in LR and HR spaces, the proposed method directly regularizes the relationship between the target patch and corresponding training set in the HR space. It avoids to deal with the tough problem of preserving local geometry in various resolutions. Taking advantage of kernel function in efficiently describing intrinsic features, we further conduct the patch-based reconstruction model in the high-dimensional kernel space for capturing nonlinear characteristics. Meanwhile, a pixel-based model is proposed to regularize the relationship of pixels in the local neighborhood, which can be employed to enhance the fuzzy details in the target HR face image. It privileges the reconstruction of pixels along the dominant orientation of structure, which is useful for preserving high-frequency information on complex edges. Finally, we combine the two reconstruction models into a unified framework. The output HR face image can be finally optimized by performing an iterative procedure. Experimental results demonstrate that the proposed face hallucination method produces superior performance than the state-of-the-art methods.

Abstract P6-05-05: Discistronic reporter screen for internal ribosome entry site (IRES) - mediated translational regulation of truncated p110 ERBB2 isoform

Background:

We and others demonstrated that truncated p110 ERBB2 (p110 t-ERBB2, also as 611CTF) is a hyperactive truncated ERBB2 isoform capable of increasing cell migration and invasion in multiple cell types in vitro, and induction of human breast epithelial cell (HMLE) xenograft formation in vivo [Ward, et al., Oncogene (2013) 32, 2463–2474]. p110 t-ERBB2 arises through alternative initiation of translation from methionine 611, however, it is unclear how regulation of its expression may be achieved. mRNA structural elements termed internal ribosome entry sites (IRESs) can initiate translation in a cap-independent manner when canonical cap-dependent translation is severely compromised. By cloning the EGFR 5' untranslated region (UTR) between the Renilla and firefly luciferase open reading frames of pRF, Webb, et al. have reported human EGFR 5' UTR sequence can initiate expression of a downstream open reading frame via an IRES [Oncogenesis (2014) 3, e134]. Therefore, we sought to identify presence of a putative IRES within the 5'UTR ERBB2 mRNA which might mediate alternative ERBB2 protein translation initiation under stress conditions and promote p110 t-ERBB2 biosynthesis.

Methods:

Discistronic reporter pRF was used as the backbone vector to detect IRES activity. Promoter-less vector pRFΔP were constructed by removing SV40 promoter via restriction digestion. The HER2 mRNA 5'UTR (from both variant 1 and variant 3) and several overlapping sequences from full length ERBB2 (p185 ERBB2) start codon to p110 t-ERBB2 start codon were cloned between the Renilla and firefly luciferase open reading frames of pRF and pRFΔP, then the resultant constructswere transiently transfected into different cell lines(BT474, SK-BR3, MCF-7, HeLa, CHO). Three control constructs pRF (empty vector control), pRF-Tub (negative control, containing βtubulin 5'UTR, which lacks IRES activity) and pRF-myc (positive control, containing the well-characterized c-myc IRES) were parallel-transfected. Luciferase expression was then quantified using a Dual Luciferase Assay Kit (Promega, Madison, WI, USA) following manufacturer's instructions. Parallel western blot analysis and qRT-PCR were also conducted.

Results:

In this report, we demonstrate that in BT474 and SK-BR3 cells, no IRES activity was detected within human ERBB2 5'UTR sequences under non-stressed conditions, or under serum-starvation, hypoxic conditions or thapsgargin-induced endoplasmic reticulum stress -- conditions when global translation was compromised.The construct pRF-+265/+1561 (within ERBB2 mRNA coding sequence, 5' to the p110 t-ERBB2 start codon) displayed a 10-21 fold increase in firefly/Renilla activity when compared with the empty control pRF and negative control pRF-Tub,consistent with the possibility that the region between +265/+1561 may contain a cryptic promoter.

Conclusions:

These data are inconsistent with the hypothesis that a 5'UTR IRES-mediated mechanism is involved in the translation of p110 t-ERBB2 isoform, and that other mechanisms are operative in alternative translational regulation/biosynthesis of p110 ERBB2 isoform.

Citation Format: Zong Y, Li Y, Liu X, Pegram MD. Discistronic reporter screen for internal ribosome entry site (IRES) - mediated translational regulation of truncated p110 ERBB2 isoform [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P6-05-05.

Comparison of retinal microvascular changes in eyes with high-tension glaucoma or normal-tension glaucoma: a quantitative optic coherence tomography angiographic study

PURPOSE

The aim of this study is to determine and compare the changes in the retinal vasculature in eyes with high-tension glaucoma (HTG) or normal-tension glaucoma (NTG).

METHODS

The right eyes of 43 HTG subjects, 33 NTG subjects, and 51 age- and sex-matched normal subjects were included in this cross-sectional study. Signals were projected from the internal limiting membrane to retinal pigment epithelium. The retinal perfused vessel densities in the peripapillary and parafoveal regions were measured automatically with optic coherence tomography angiography and the split-spectrum amplitude-decorrelation angiography algorithm.

RESULTS

Compared with normal eyes, glaucomatous eyes had a smaller retinal nerve fibre layer (RNFL) thickness, smaller full parafoveal retinal thickness, and lower retinal perfused vessel density (PVD) in the peripapillary and parafoveal regions (all P < 0.01). The visual field, RNFL and retinal thicknesses, and PVD in the parafoveal region in the HTG eyes were similar to those in the NTG eyes. However, the NTG eyes had a significantly lower mean PVD than the HTG eyes in the peripapillary region. When the different sectors of the peripapillary region were studied, the difference was still significant in most sectors (all P < 0.05), except the inferotemporal sector (P = 0.676).

CONCLUSIONS

The retinal perfused vessel density is significantly reduced in HTG and NTG eyes, and more prominently in the peripapillary region in NTG eyes.

Domain Regeneration for Cross-Database Micro-Expression Recognition

Recently, micro-expression recognition has attracted lots of researchers' attention due to its potential value in many practical applications, e.g., lie detection. In this paper, we investigate an interesting and challenging problem in micro-expression recognition, i.e., cross-database micro-expression recognition, in which the training and testing samples come from different micro-expression databases. Under this problem setting, the consistent feature distribution between the training and testing samples originally existing in conventional micro-expression recognition would be seriously broken and hence the performance of most current well-performing micro-expression recognition methods may sharply drop. In order to overcome it, we propose a simple yet effective framework called Domain Regeneration (DR) in this paper. DR framework aims at learning a domain regenerator to regenerate the micro-expression samples from source and target databases respectively such that they can abide by the same or similar feature distributions. Thus, we are able to use the classifier learned based on the labeled source micro-expression samples to predict the label information of the unlabeled target micro-expression samples. To evaluate the proposed DR framework, we conduct extensive cross-database micro-expression recognition experiments designed based on SMIC and CASME II databases. Experimental results show that compared with recent state-of-the-art cross-database emotion recognition methods, the proposed DR framework has more promising performance.

Differential Modulation of GABAA and NMDA Receptors by an α7-nicotinic Acetylcholine Receptor Agonist in Chronic Glaucoma

Presynaptic modulation of γ-aminobutyric acid (GABA) release by an alpha7 nicotinic acetylcholine receptor (α7-nAChR) agonist promotes retinal ganglion cell (RGC) survival and function, as suggested by a previous study on a chronic glaucomatous model from our laboratory. However, the role of excitatory and inhibitory amino acid receptors and their interaction with α7-nAChR in physiological and glaucomatous events remains unknown. In this study, we investigated GABA_A and N-methyl-D-aspartate (NMDA) receptor activity in control and glaucomatous retinal slices and the regulation of amino acid receptor expression and function by α7-nAChR. Whole-cell patch-clamp recordings from RGCs revealed that the α7-nAChR specific agonist PNU-282987 enhanced the amplitude of currents elicited by GABA and reduced the amplitude of currents elicited by NMDA. The positive modulation of GABA_A receptor and the negative modulation of NMDA receptor (NMDAR) by PNU-282987-evoked were prevented by pre-administration of the α7-nAChR antagonist methyllycaconitine (MLA). The frequency and the amplitude of glutamate receptor-mediated miniature glutamatergic excitatory postsynaptic currents (mEPSCs) were not significantly different between the control and glaucomatous RGCs. Additionally, PNU-282987-treated slices showed no alteration in the frequency or amplitude of mEPSCs relative to control RGCs. Moreover, we showed that expression of the α1 subunit of the GABA_A receptor was downregulated and the expression of the NMDAR NR2B subunit was upregulated by intraocular pressure (IOP) elevation, and the changes of high IOP were blocked by PNU-282987. In conclusion, retina GABA_A and NMDARs are modulated positively and negatively, respectively, by activation of α7-nAChR in in vivo chronic glaucomatous models.

AetMYC1, the Candidate Gene Controlling the Red Coleoptile Trait in Aegilops tauschii Coss. Accession As77

The red coleoptile trait can help monocotyledonous plants withstand stresses, and key genes responsible for the trait have been isolated from Triticum aestivum, Triticum urartu, and Triticum monococcum, but no corresponding research has been reported for Aegilops tauschii. In this research, transcriptome analysis was performed to isolate the candidate gene controlling the white coleoptile trait in Ae. tauschii. There were 5348 upregulated, differentially-expressed genes (DEGs) and 4761 downregulated DEGs in red coleoptile vs. white coleoptile plants. Among these DEGs, 12 structural genes and two transcription factors involved in anthocyanin biosynthesis were identified. The majority of structural genes showed lower transcript abundance in the white coleoptile of accession ‘As77’ than in the red coleoptile of accession ‘As60’, which implied that transcription factors related to anthocyanin biosynthesis could be the candidate genes. The MYB and MYC transcription factors AetMYB7D and AetMYC1 were both isolated from Ae. tauschii accessions ‘As60’ and ‘As77’, and their transcript levels analyzed. The coding sequence and transcript level of AetMYB7D showed no difference between ‘As60’ and ‘As77’. AetMYC1p encoded a 567-amino acid polypeptide in ‘As60’ containing the entire characteristic domains, bHLH-MYC_N, HLH, and ACT-like, belonging to the gene family involved in regulating anthocyanin biosynthesis. AetMYC1w encoded a 436-amino acid polypeptide in ‘As77’ without the ACT-like domain because a single nucleotide mutation at 1310 bp caused premature termination. Transient expression of AetMYC1p induced anthocyanin biosynthesis in ‘As77’ with the co-expression of AetMYB7D, while AetMYC1w could not cause induced anthocyanin biosynthesis under the same circumstances. Moreover, the transcript abundance of AetMYC1w was lower than that of AetMYC1p. AetMYC1 appears to be the candidate gene controlling the white coleoptile trait in Ae. tauschii, which can be used for potential biotech applications, such as producing new synthetic hexaploid wheat lines with different coleoptile colors.

Cannabinoids Regulate the Diameter of Pericyte-Containing Retinal Capillaries in Rats

BACKGROUND/AIMS

Cannabinoids are vasoactive substances that act as key regulators of arterial tone in the blood vessels supplying peripheral tissues and the central nervous system. We therefore investigated the effect of cannabinoids on retinal capillaries and pericytes.

METHODS

The effects of cannabinoids on capillary diameters were determined using an ex vivo whole-mount rat retinal model. Western blotting, quantitative PCR, and immunohistochemistry were performed to explore the underlying mechanism.

RESULTS

Endogenous cannabinoid 2-arachidonoylglycerol and anandamide and exogenous cannabinoid (R-(+)-WIN55212-2) dilated the noradrenaline-precontracted capillaries in a concentration-dependent manner (1 µM to 0.1 mM). The extent of vasorelaxation was positively correlated with changes in pericyte width. The effects of R-(+)-WIN55212-2 on vasorelaxation and pericyte width were inhibited by a cannabinoid receptor type-1 (CB1) antagonist, AM251 or rimonabant (SR141716A), the nitric oxide synthase inhibitor l-NAME, and the guanylate cyclase inhibitor ODQ. They were also abolished by the removal of the endothelium, but not by the cannabinoid receptor-2 antagonist SR144528, the endothelial cannabinoid receptor antagonist O-1918, or the cyclooxygenase inhibitor indomethacin.

CONCLUSION

The exogenous cannabinoid R-(+)-WIN55212-2 promotes the vasorelaxation of pericyte-containing rat retinal capillaries. This effect of R-(+)-WIN55212-2 is dependent on CB1 and the nitric oxide-cyclic guanosine monophosphate pathway, and requires an intact endothelium.

[Clinical utility study of 21-gene assay in 927 Chinese patients with early breast cancer]

Objective: To investigate the distribution patterns of 21-gene assay and its influencing factors in Chinese patients with early breast cancer. Methods: Nine hundred and twenty-seven early breast cancer patients were retrospectively recruited from January 2009 to December 2015 at Ruijin Hospital, Shanghai Jiaotong University School of Medicine. The 21-gene reverse transcriptase-polymerase chain reaction(RT-PCR) assay were conducted in paraffin-embedded tumor tissues to calculate the Recurrence Score(RS). Immunohistochemistry(IHC) assay was used to measure the expression levels of estrogen receptor(ER), progesterone receptor(PR) and Ki-67. Concordances of RT-PCR and IHC results were assessed. Correlations of RS and classical clinicopathological factors were evaluated, and logistic regression were applied to determine independent predictive factors for RS. Results: The median RS of 927 patients was 23(range: 0~90), and the proportions of patients categorized as having a low, intermediate, or high risk were 26.5%, 47.7% and 25.8%, respectively. The distribution of RS varied significantly according to different tumor grade, T stage, PR status, Ki-67 index and molecular subtypes(P<0.05 for all). Grade, PR status and Ki-67 index were independent predictive factors for RS. ER, PR status and Ki-67 index showed significantly correlation between RT-PCR and IHC assays, and the concordance rates for ER and PR status were 98.7% and 87.8%, respectively. Conclusions: RS significantly correlated with tumor grade, T stage, PR status, Ki-67 index and subtypes. Grade, PR status and Ki-67 index can independently predict RS. Remarkable concordances of ER, PR status and Ki-67 index are found between RT-PCR and IHC assays.

Retinal Vascular Autoregulation during Phase IV of the Valsalva Maneuver: An Optical Coherence Tomography Angiography Study in Healthy Chinese Adults

The impairment of retinal vascular autoregulation can be an early manifestation of many systemic and ocular diseases. Therefore, quantifying retinal vascular autoregulation in a non-invasive manner is very important. This study evaluated the effects of a Valsalva maneuver (VM)-induced blood pressure increases on retinal vascular autoregulation. Parafoveal and peripapillary retinal vessel density were measured with optical coherence tomography angiography before (baseline) and 5 s after each subject completed a VM (Phase IV [VM-IV]). Hemodynamic parameters and intraocular pressure (IOP) were examined. Blood pressure (systolic, diastolic, and mean arterial) and ocular perfusion pressure significantly increased during VM-IV, but IOP and heart rate (HR) did not change. The VM-induced blood pressure overshoot significantly decreased parafoveal (8.43%) and peripapillary (1.57%) perfused retinal vessel density (both P < 0.001). The response in the parafoveal region was greater than that in the peripapillary region (P < 0.001), and was age-dependent (r = 0.201, P < 0.05). Foveal avascular zone area detectable with OCTA significantly increased from baseline by 6.63% during VM-IV (P < 0.05). Autoregulatory responses to a VM did not show gender-related differences in either retinal region. The autoregulation of retinal vessels may vary in different regions of the fundus. Optical coherence tomography angiography could be a useful method for evaluating the autoregulation of the retinal vascular system.

[Effect of 21-gene recurrence score on chemotherapy decisions for patients with estrogen receptor-positive, epidermal growth factor receptor 2-negative and lymph node-negative early stage-breast cancer]

Objective: To investigate the effect of 21-gene recurrence score on adjuvant chemotherapy decisions for patients with estrogen receptor (ER)-positive, epidermal growth factor receptor 2 (HER-2)-negative and lymph node (LN)-negative early stage-breast cancer. Methods: One hundred and forty-eight patients with ER+ , HER-2- and LN- early stage breast cancer were recruited in the Ruijin hospital, Shanghai Jiao Tong University School of Medicine. The 21-gene recurrence score (RS)assay was performed and systemic therapeutic decisions were made before and after knowing the RS results under multidisciplinary discussion. The effects of RS assay and the other influential factors on adjuvant chemotherapy decision were further analyzed. Results: After knowing the RS results, treatment decisions were changed in 26 out of 148 patients(17.6%). Among them, 9 out of 26 patients were not recommended for chemotherapy; 16 of 26 had treatment recommendation changed to chemotherapy, and chemotherapy regimen was changed in the last one patient. Multivariate analysis showed that RS, age and histological grade were independent factors of decision-making for adjuvant chemotherapy. Conclusion: Our results suggest that 21-gene recurrence score significantly influences decision making for adjuvant chemotherapy in patients with ER+ , HER-2- and LN- early stage breast cancer.

Erlotinib for advanced hepatocellular carcinoma. A systematic review of phase II/III clinical trials

Objectives:

To evaluate the efficacy and safety of erlotinib for the treatment of advanced hepatocellular carcinoma (HCC).

Methods:

A systematic literature search was undertaken in June 2015. Phase II/III trials of erlotinib for the treatment of advanced HCC were included. A descriptive analysis was applied. The study was conducted in College of Medicine, Honghui Hospital, Xi’an Jiaotong University, Xi’an, China, between June 2015 and January 2016.

Results:

Ten trials, comprising 9 phase II and one phase III trial, were included in the systematic review. The tumor response rate was 0% in 4 of the phase II trials, <10% in 3 of the phase II trials and the phase III trial, and >20% in 2 of the phase II trials. The disease control rate was 42.5-79.6% in most studies. Three studies reported a median progression-free survival (PFS) of 6.5-9.0 months, although PFS was <3.5 months in most studies. Most trials reported a median overall survival of 6.25-15.65 months. The most frequent grade 3/4 toxicities were fatigue (11.9%), diarrhea (10%), increased alanine and aspartate transaminases (7.3%), and rash/desquamation (6.9%).

Conclusion:

Erlotinib provides efficacious and well-tolerated treatment for advanced HCC. However, more detailed investigations of HCC pathogenesis and evaluation of sensitive patient subsets are needed to improve outcomes of patients with advanced HCC. Additional well-designed, randomized, controlled trials are needed to evaluate the efficacy and safety of erlotinib as monotherapy or combination with other drugs for advanced HCC.

Viscocanalostomy combined with trabeculotomy and mitomycin C in the treatment of primary congenital glaucoma

AIM

To evaluate the long-term outcome of viscocanalostomy combined with trabeculotomy and mitomycin C in the treatment of primary congenital glaucoma.

METHODS

This is a retrospective study. Forty-two eyes of 26 patients with primary congenital glaucoma were enrolled. Intraocular pressure (IOP), corneal diameter (mm) and cup/disc (C/D) were measured before and after the surgery respectively. Follow-up period was 30mo.

RESULTS

The mean preoperative IOP was 30.6±7.35 mm Hg. Of the 42 eyes, 2 eyes were required conversion to trabeculectomy for the absence of Schlemm's canal. Of remained 40 eyes, 38 eyes (95%) achieved successful IOP control. The average postoperative IOP was 11.69±4.18 mm Hg at 12mo. The mean reduction was 18.91 mm Hg (P<0.0001). Eighteen (75%) eyes presented a reduction in corneal diameter, and 25 (62.5%) eyes presented a C/D ratio reversal after the surgery. There was no serious complication in any patients over the follow-up period.

CONCLUSION

Viscocanalostomy combined with trabeculotomy and mitomycin C is useful in the management of primary congenital glaucoma.

Relationship Between Retinal Perfusion and Retinal Thickness in Healthy Subjects: An Optical Coherence Tomography Angiography Study

Purpose

To investigate the relationship between retinal perfusion and retinal thickness in the peripapillary and macular areas of healthy subjects.

Methods

Using spectral-domain optic coherence tomography and split-spectrum amplitude decorrelation angiography (SSADA) algorithm, retinal perfusion and retinal thicknesses in the macular and peripapillary areas were measured in healthy volunteers, and correlations among these variables were analyzed.

Results

Overall, 64 subjects (121 eyes) including 28 males and 36 females with a mean ± SD age of 38 ± 13 years participated. Linear mixed-models showed that vessel area density was significantly correlated with the inner retinal thickness (from the inner limiting membrane to the outer border of the inner nucleus layer; P < 0.05), but not with the thickness of the full retina (P > 0.05) in the parafoveal area. The area of the foveal capillary-free zone was negatively correlated with the inner and full foveal thicknesses (all P < 0.001). In the peripapillary area, the vessel area density was positively correlated with the thickness of the retinal nerve fiber layer (P < 0.001).

Conclusions

In healthy subjects, retinal perfusion in small vessels was closely correlated with the thickness of the inner retinal layers in both the macular and peripapillary areas.

[Prognostic factors of postoperative delayed gastric emptying after pancreaticoduodenectomy: a predictive model]

Objective: To study the prognostic factors of delayed gastric emptying(DGE) after pancreaticoduodenectomy(PD) and construct a prognostic predictive model for clinical application. Methods: Clinic data of 401 consecutive patients who underwent PD between January 2012 and July 2016 in the First Affiliated Hospital of Harbin Medical University were retrospectively collected and analyzed. The patients were randomly selected to modeling group(n=299) and validation group(n=102) at a ratio of 3∶1. The data of modeling group were subjected to univariate and multivariate analysis for prognostic factors and to construct a prognostic predictive model of DGE after PD. The data of validation group were applied to test the prognostic predictive model. Results: DGE after PD occurred in 35 of 299 patients(11.7%) in the modeling group. The multivariate analysis of the modeling group showed that upper abdominal operation history(χ(2)=6.533, P=0.011), diabetes mellitus(χ(2)=17.872, P=0.000), preoperative hemoglobin <90 g/L(χ(2)=14.608, P=0.000) and pylorus-preserving pancreaticoduodenectomy(PPPD)(χ(2)=8.811, P=0.003) were associated with DGE after PD independently. A prognostic predictive model of DGE after PD was constructed based on these factors and successfully tested. The area under the receiver operating characteristic(ROC) curve was 0.761(95%CI: 0.666-0.856) of the modeling group and 0.750(95% CI: 0.577-0.923) of the validation group. Conclusions: Upper abdominal operation history, diabetes mellitus, preoperative hemoglobin<90 g/L and PPPD are associated with DGE after PD independently. The preoperative assessment of a patient's prognostic for DGE after PD is feasible. The model is a valid tool to take precautions against DGE after PD.

Precise base editing in rice, wheat and maize with a Cas9-cytidine deaminase fusion

Targeted base editing in plants without the need for a foreign DNA donor or double-stranded DNA cleavage would accelerate genome modification and breeding in a wide array of crops. We used a CRISPR-Cas9 nickase-cytidine deaminase fusion to achieve targeted conversion of cytosine to thymine from position 3 to 9 within the protospacer in both protoplasts and regenerated rice, wheat and maize plants at frequencies of up to 43.48%.

Abstract P5-16-29: Nanoparticle albumin-bound paclitaxel as neoadjuvant chemotherapy of breast cancer: A meta-analysis

Background: Nanoparticle albumin-bound paclitaxel (nab-Paclitaxel), a novel solvent-free taxane-based regimen, was hypothesized to have enhanced drug transport to tumors, shorter infusion schedules and no need for premedication. The value of nab-Paclitaxel in neoadjuvant systemic therapy (NST) for breast cancer remains uncertain. We performed a meta-analysis to assess efficacy and toxicity of nab-Paclitaxel compared to conventional taxane regimens (paclitaxel, docetaxel) within randomized clinical trials.

Methods: A systematic search was performed using the medical subject heading (MeSH) terms ''breast neoplasms'', as well as (1) breast cancer; AND (2) nab-Paclitaxel OR nanoparticle paclitaxel; AND (3) neoadjuvant OR preoperative OR primary systemic in both Pubmed databases and proceedings of oncologic meetings including ASCO, ESMO and SABCS. Pooled rates of pathological complete response(pCR), odds ratios (ORs) and 95% confidence intervals (CIs) were calculated using fixed-effect or random-effect model to determine the effect of neoadjuvant nab-paclitaxel.

Results: Twenty-one studies with 2357 patients were included, 3 of which (GeparSepto[1], ETNA[2], Showa trial[3]) were randomized clinical trials. The aggregate pCR rate (ypT0/is ypN0) was 32% (95% CI 25-38%) in unselected breast cancer patients and was 14%(95% CI 11-17%), 41%(95% CI 38-45%), 54%(95% CI 43-66%) in hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2-), triple negative breast cancer(TNBC), HER2+ patients, respectively. Within the HER2+ population, pCR rate was 61%(95% CI 47-74%) for HR- and 40%(95% CI 28-52%) for HR+ tumors. Regarding randomized clinical trials, the probability of achieving pCR was significantly higher in the nab-paclitaxel group than in the conventional taxanes group (OR=1.383, 95%CI 1.141-1.676, p=0.001). A funnel plot of the effect size for each randomized trial against the precision showed no asymmetry, which indicating no potential publication bias. In the safety analysis (GeparSepto[1], ETNA[2]), hematological toxic effects were generally equivalent in nab-paclitaxel and paclitaxel group. For non-hematological toxic effects, all grades and grade≥ 3 peripheral sensory neuropathy occurred more frequently with nab-paclitaxel compared to paclitaxel (all grades, OR=2.090, 95%CI 1.016-4.302, p=0.045; grade≥ 3, OR=3.766, 95%CI 2.324-6.100, p&lt;0.001). Hypersensitivity was more common with paclitaxel than nab-paclitaxel at any grade and grade≥ 3. Other non-hematological toxic effects did not significantly differ between two groups.

Conclusion: nab-Paclitaxel is an effective antitumor drug in NST of breast cancer, especially for TNBC and HER2+ tumors, in terms of pCR. Exchange of nab-Paclitaxel for conventional taxanes could significantly improve pCR rate with reasonable toxicities.

Clinical trial information: 1.Lancet Oncol.2016,17:345-56.; 2.J Clin Oncol.2016,34(suppl; abstract 502).; 3.J Clin Oncol.2015,33(suppl; abstract 136).

Citation Format: Zong Y, Wu J, Shen K. Nanoparticle albumin-bound paclitaxel as neoadjuvant chemotherapy of breast cancer: A meta-analysis [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 P5-16-29.

Allelic Variation and Transcriptional Isoforms of Wheat TaMYC1 Gene Regulating Anthocyanin Synthesis in Pericarp

Recently the TaMYC1 gene encoding bHLH transcription factor has been isolated from the bread wheat (Triticum aestivum L.) genome and shown to co-locate with the Pp3 gene conferring purple pericarp color. As a functional evidence of TaMYC1 and Pp3 being the same, higher transcriptional activity of the TaMYC1 gene in colored pericarp compared to uncolored one has been demonstrated. In the current study, we present additional strong evidences of TaMYC1 to be a synonym of Pp3. Furthermore, we have found differences between dominant and recessive Pp3(TaMyc1) alleles. Light enhancement of TaMYC1 transcription was paralleled with increased AP accumulation only in purple-grain wheat. Coexpression of TaMYC1 and the maize MYB TF gene ZmC1 induced AP accumulation in the coleoptile of white-grain wheat. Suppression of TaMYC1 significantly reduced AP content in purple grains. Two distinct TaMYC1 alleles (TaMYC1p and TaMYC1w) were isolated from purple- and white-grained wheat, respectively. A unique, compound cis-acting regulatory element had six copies in the promoter of TaMYC1p, but was present only once in TaMYC1w. Analysis of recombinant inbred lines showed that TaMYC1p was necessary but not sufficient for AP accumulation in the pericarp tissues. Examination of larger sets of germplasm lines indicated that the evolution of purple pericarp in tetraploid wheat was accompanied by the presence of TaMYC1p. Our findings may promote more systematic basic and applied studies of anthocyanins in common wheat and related Triticeae crops.

Targeted Mutagenesis in Hexaploid Bread Wheat Using the TALEN and CRISPR/Cas Systems

The use of sequence-specific transcription activator-like effector nucleases (TALENs) and the clustered regularly interspaced short palindromic repeats-associated system (CRISPR/Cas9) have provided powerful reverse genetic approaches to the targeted modification of genomes in numerous organisms. Both systems have been employed to generate loss-of-function alleles in bread wheat, by targeting multiple and single copies of genes. Here we present protocols for modifying the wheat genome using the two systems. The protocols include the design of TALEN and CRISPR/Cas9 target sites and their construction, evaluation of their activities in protoplasts, transformation of plants, and mutation screening.

Aggravation of spinal cord compromise following new osteoporotic vertebral compression fracture prevented by teriparatide in patients with surgical contraindications

Patients with spinal cord deficits following new unstable osteoporotic compression fracture and surgical contraindications were considered to receive conservative treatment. Teriparatide was better than alendronate at improving bone mineral density and bone turnover parameters, as well as preventing aggravation of spinal cord compromise.

INTRODUCTION

This study compared the preventive effects of teriparatide and alendronate on aggravation of spinal cord compromise following new unstable osteoporotic vertebral compression fracture (OVCF) in patients with surgical contraindications.

METHODS

This was a 12-month, randomized, open-label study of teriparatide versus alendronate in 49 patients with new unstable OVCF and surgical contraindications. Neurological function was evaluated using modified Japanese Orthopedic Association (mJOA) score (11-point scale, the maximum score of 11 implies normalcy). Visual analog scale (VAS) scores, kyphotic angles, anterior-border heights and diameters of the spinal canal of the fractured vertebrae, any incident of new OVCFs (onset of OVCF during follow-up), spine bone mineral density (BMD), and serum markers of bone resorption and bone formation were also examined at baseline and 1, 3, 6, and 12 months after initiation of the medication regimen.

RESULTS

At 12 months, mean mJOA score had improved in the teriparatide group and decreased in the alendronate group. Mean concentrations of bone formation and bone resorption biomarkers, mean spine BMD, and mean anterior-border height and spinal canal diameter of the fractured vertebrae were significantly greater in the teriparatide group than in the alendronate group. Mean VAS score, mean kyphotic angle of the fractured vertebrae, and incidence of new OVCFs were significantly smaller in the teriparatide group than in the alendronate group.

CONCLUSIONS

In patients with neurological deficits following new unstable OVCF and with surgical contraindications, teriparatide was better than alendronate at improving the BMD and the bone turnover parameters, as well as preventing aggravation of spinal cord compromise.

Amentoflavone prevents sepsis-associated acute lung injury through Nrf2-GCLc-mediated upregulation of glutathione

Sepsis is a serious medical problem and is one of the main causes of high mortality in intensive care units. Fifty percent of patients with severe sepsis will develop acute lung injury (ALI). Amentoflavone (AMF) is a polyphenolic compound possessing potent anti-inflammatory activities. The study aimed to explore the protective effects of AMF against ALI in cecal ligation and puncture (CLP)-induced septic rats. The results showed that AMF administration protected against septic ALI, as reflected by marked amelioration of histological injury of lung tissues and decrease of pulmonary edema in CLP-treated rats. AMF ameliorated CLP-induced increase of systemic and lung TNFα and IL-1β and binding activity of p65 NF-κB, indicating the inhibition of inflammation. Moreover, AMF prevented CLP-induced oxidative stress, as evidenced by increase of oxygen consumption rate, decrease of TBARS content, increase of SOD activity and GSH level in lung tissue of CLP-treated rats. CLP resulted in significant decrease of mRNA expression of Nrf2 and GCLc, which was inhibited by AMF. AMF-induced protective effects on ALI, inflammation, and oxidative stress were inhibited by lentivirus shRNA-mediated silence of Nrf2 and buthionine sulphoximine (BSO), an inhibitor of GSH synthesis. AMF increased Nrf2-binding activity in GCLc promoters in lung tissue of CLP-treated rats. The results suggested that AMF protected against ALI in septic rats through upregulation of Nrf2-GCLc signaling, enhancement of GSH antioxidant defense, reduction of oxidative stress and final amelioration of inflammation and histological injury of lung. The data provide new therapeutic options for the treatment of sepsis-associated ALI.

Gene replacements and insertions in rice by intron targeting using CRISPR-Cas9

Sequence-specific nucleases have been exploited to create targeted gene knockouts in various plants(1), but replacing a fragment and even obtaining gene insertions at specific loci in plant genomes remain a serious challenge. Here, we report efficient intron-mediated site-specific gene replacement and insertion approaches that generate mutations using the non-homologous end joining (NHEJ) pathway using the clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein 9 (Cas9) system. Using a pair of single guide RNAs (sgRNAs) targeting adjacent introns and a donor DNA template including the same pair of sgRNA sites, we achieved gene replacements in the rice endogenous gene 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) at a frequency of 2.0%. We also obtained targeted gene insertions at a frequency of 2.2% using a sgRNA targeting one intron and a donor DNA template including the same sgRNA site. Rice plants harbouring the OsEPSPS gene with the intended substitutions were glyphosate-resistant. Furthermore, the site-specific gene replacements and insertions were faithfully transmitted to the next generation. These newly developed approaches can be generally used to replace targeted gene fragments and to insert exogenous DNA sequences into specific genomic sites in rice and other plants.