Differentiation of Pelvic Osteosarcoma and Ewing Sarcoma Using Radiomic Analysis Based on T2-Weighted Images and Contrast-Enhanced T1-Weighted Images

Objective. To determine if osteosarcoma (OS) and Ewing sarcoma (EWS) of the pelvis based on MRI can be differentiated using radiomic analysis. Materials and Methods. In this study, 3.0 T magnetic resonance (MR) data of 66 patients (40 males and 26 females, mean age 27.6±13.9 years) with pathologically confirmed OS or EWS of the pelvis (35 with OS and 31 with EWS) taken from April 2013 to December 2017 were retrospectively reviewed. T2-weighted fat-saturated (T2-FS) and contrast-enhanced T1-weighted (CET1) images were manually segmented, and imaging features were extracted. Independent-sample t-test, Spearman’s test, and the least absolute shrinkage and selection operator (LASSO) method were used to select the most useful features from the original data set. The performance of radiomic analysis was investigated by the area under the receiver operating characteristic (ROC) curve (AUC) analysis. Results. 385 initial features were extracted from T2-FS and CET1 MR data. Nine features from T2-FS and 7 features from CET1 were selected by using the LASSO method. The radiomic analysis to differentiate OS and EWS of the pelvis based on T2-FS and CET1 images using the aforementioned selected features achieved AUC values of 0.881 (95% confidence interval (CI): 0.799–0.963) and 0.765 (95% CI: 0.652–0.878), respectively. Conclusion. Radiomic analysis showed potential in differentiating OS from EWS of the pelvis, in which T2-FS demonstrated better diagnostic value. To differentiate OS from EWS of the pelvis using our multiparametric MRI-based radiomic analysis could preoperatively improve diagnostic accuracy and greatly contribute to therapy planning

Transcriptome Analysis in Haematococcus pluvialis: Astaxanthin Induction by Salicylic Acid (SA) and Jasmonic Acid (JA)

Haematococcus pluvialis is an astaxanthin-rich microalga that can increase its astaxanthin production by salicylic acid (SA) or jasmonic acid (JA) induction. The genetic transcriptome details of astaxanthin biosynthesis were analyzed by exposing the algal cells to 25 mg/L of SA and JA for 1, 6 and 24 hours, plus to the control (no stress). Based on the RNA-seq analysis, 56,077 unigenes (51.7%) were identified with functions in response to the hormone stress. The top five identified subcategories were cell, cellular process, intracellular, catalytic activity and cytoplasm, which possessed 5600 (~9.99%), 5302 (~9.45%), 5242 (~9.35%), 4407 (~7.86%) and 4195 (~7.48%) unigenes, respectively. Furthermore, 59 unigenes were identified and assigned to 26 putative transcription factors (TFs), including 12 plant-specific TFs. They were likely associated with astaxanthin biosynthesis in Haematococcus upon SA and JA stress. In comparison, the up-regulation of differential expressed genes occurred much earlier, with higher transcript levels in the JA treatment (about 6 h later) than in the SA treatment (beyond 24 h). These results provide valuable information for directing metabolic engineering efforts to improve astaxanthin biosynthesis in H. pluvialis

Comparative fatty acid transcriptomic test and iTRAQ-based proteomic analysis in Haematococcus pluvialis upon salicylic acid (SA) and jasmonic acid (JA) inductions

Astaxanthin in microalga Haematococcus pluvialis has been studied for years, but there is still little known about the metabolic variation of astaxanthin biosynthesis. Thus, iTRAQ-based proteomic data were analysed on H. pluvialis in response to salicylic acid (SA) and jasmonic acid (JA) inductions with a time course. While a subset of 257 proteins was screened in the JA treatment with 119 proteins up-regulated and 138 proteins down-regulated, 272 proteins were in the SA treatment, with 123 of significant up-regulation and 149 of down-regulation. Meanwhile, proteins enriched in lipid metabolism were differentially expressed in both JA and SA treatments over time. This was consistent with the genetic transcriptional expressions involved in the fatty acid biosynthesis. However, the proteins' coding for lipid metabolism was not correlated to the differential expressions of FA biosynthesis genes in either JA or SA inductions. These results provide a new insight on the interrelationship between FA synthesis genes' regulations and FA/astaxanthin biosynthesis, and also highlight the importance of protein post-translational modifications for the astaxanthin accumulation. Furthermore, about 61 differentially expressed proteins were identified as putative transcription factors (TFs) at the translational level and assigned to 24 families. Many different TFs were observed between JA and SA treatments, suggesting different signaling pathways involved in the JA and SA induced H. pluvialis cells. These results also form a fundamental basis to facilitate future research towards genetically bioengineered astaxanthin biosynthesis in H. pluvialis

Up and down regulated genes involved in carotenoid pathway analysis.

<p>Up and down regulated genes involved in carotenoid pathway analysis.</p

The number of up-regulated (red) and down-regulated (green) unigenes in <i>Haematococcus pluvialis</i> on JA and SA treatments.

<p>The number of up-regulated (red) and down-regulated (green) unigenes in <i>Haematococcus pluvialis</i> on JA and SA treatments.</p

Differential epression of genes involved in the carotenoid biosynthesis pathway of<i>Haematococcus pluvialis</i>.

<p>The color chart represents up- (red) and down-regulated (green) folds. The slash in the square indicates a significant differential-epression at the level of > 2 folds, FDR < 0.001, RPKM > 20. IPI- isopentenyl diphosphate isomerase; GGPS- geranylgeranyl diphosphate synthase; PSY- phytoene synthase; PDS- phytoene desaturase; ZDS- zeta-carotene desaturase; LCYB- lycopene beta-cyclase; CRTR-B- carotenoid hydroylase; BKT/CRTO- beta-carotene ketolase.</p

Gene Ontology (GO) classification of unigenes in <i>H</i>. <i>pluvialis</i>: molecular function (A), cellular component (B) and biological process domains (C).

<p>(The -ais indicates the subcategories and the y-ais indicates the number of unigenes).</p

Venn diagrams showing genes unique and shared between different treatments in <i>Haemotococcus pluvialis</i>.

<p>Each colour represents a sample (as labelled) and the numbers indicate the amount of genes in the region. (A) Comparative result of SA-treated samples (SA1, SA6 and SA24) and the control (N); (B) Comparative result of JA-treated samples (JA1, JA6 and JA24) and the control (N).</p