Meta-analysis of transcriptome data identifies a novel 5-gene pancreatic adenocarcinoma classifier

Purpose: Pancreatic ductal adenocarcinoma (PDAC) is largely incurable due to late diagnosis. Superior early detection biomarkers are critical to improving PDAC survival and risk stratification. Experimental Design: Optimized meta-analysis of PDAC transcriptome datasets identified and validated key PDAC biomarkers. PDAC-specific expression of a 5-gene biomarker panel was measured by qRT-PCR in microdissected patient-derived FFPE tissues. Cell-based assays assessed impact of two of these biomarkers, TMPRSS4 and ECT2, on PDAC cells. Results: A 5-gene PDAC classifier (TMPRSS4, AHNAK2, POSTN, ECT2, SERPINB5) achieved on average 95% sensitivity and 89% specificity in discriminating PDAC from non-tumor samples in four training sets and similar performance (sensitivity = 94%, specificity = 89.6%) in five independent validation datasets. This classifier accurately discriminated PDAC from chronic pancreatitis (AUC = 0.83), other cancers (AUC = 0.89), and non-tumor from PDAC precursors (AUC = 0.92) in three independent datasets. Importantly, the classifier distinguished PanIN from healthy pancreas in the PDX1-Cre;LSL-KrasG12D PDAC mouse model. Discriminatory expression of the PDAC classifier genes was confirmed in microdissected FFPE samples of PDAC and matched surrounding non-tumor pancreas or pancreatitis. Notably, knock-down of TMPRSS4 and ECT2 reduced PDAC soft agar growth and cell viability and TMPRSS4 knockdown also blocked PDAC migration and invasion. Conclusions: This study identified and validated a highly accurate 5-gene PDAC classifier for discriminating PDAC and early precursor lesions from non-malignant tissue that may facilitate early diagnosis and risk stratification upon validation in prospective clinical trials. Cell-based experiments of two overexpressed proteins encoded by the panel, TMPRSS4 and ECT2, suggest a causal link to PDAC development and progression, confirming them as potential therapeutic targets

Meta-analysis of transcriptome data identifies a novel 5-gene pancreatic adenocarcinoma classifier

Purpose Pancreatic ductal adenocarcinoma (PDAC) is largely incurable due to late diagnosis. Superior early detection biomarkers are critical to improving PDAC survival and risk stratification. Experimental Design Optimized meta-analysis of PDAC transcriptome datasets identified and validated key PDAC biomarkers. PDAC-specific expression of a 5-gene biomarker panel was measured by qRT-PCR in microdissected patient-derived FFPE tissues. Cell-based assays assessed impact of two of these biomarkers, TMPRSS4 and ECT2, on PDAC cells. Results: A 5-gene PDAC classifier (TMPRSS4, AHNAK2, POSTN, ECT2, SERPINB5) achieved on average 95% sensitivity and 89% specificity in discriminating PDAC from non-tumor samples in four training sets and similar performance (sensitivity = 94%, specificity = 89.6%) in five independent validation datasets. This classifier accurately discriminated PDAC from chronic pancreatitis (AUC = 0.83), other cancers (AUC = 0.89), and non-tumor from PDAC precursors (AUC = 0.92) in three independent datasets. Importantly, the classifier distinguished PanIN from healthy pancreas in the PDX1-Cre;LSL-KrasG12D PDAC mouse model. Discriminatory expression of the PDAC classifier genes was confirmed in microdissected FFPE samples of PDAC and matched surrounding non-tumor pancreas or pancreatitis. Notably, knock-down of TMPRSS4 and ECT2 reduced PDAC soft agar growth and cell viability and TMPRSS4 knockdown also blocked PDAC migration and invasion. Conclusions: This study identified and validated a highly accurate 5-gene PDAC classifier for discriminating PDAC and early precursor lesions from non-malignant tissue that may facilitate early diagnosis and risk stratification upon validation in prospective clinical trials. Cell-based experiments of two overexpressed proteins encoded by the panel, TMPRSS4 and ECT2, suggest a causal link to PDAC development and progression, confirming them as potential therapeutic targets

Static and dynamic analysis of the mitral valve annulus in normal subjects: a three-dimensional transthoracic echocardiography study

Reference values for mitral valve annulus (MVA) by 3D transthoracic echo (3D-TTE) are lacking. Thus, we acquired 3D-TTE data sets ofMV (33+4 vps) in 119 healthy volunteers (44+14 yrs; 55 M). A prototype software for 3D TTE (4D MVanalysis 2.3, TomTec, D) was used to measure MVA parameters atMV closure, peak-minim,mid- and end- systole.We excluded 9 subjects due to poor MV tracking (feasibility 93%). MVA reached lowest area close afterMVclosure (MVAareachange=29+5%), mostlydue to antero-posteriordiameter shortening (20+7%) (Figure). Lateral-medial diameter and circumference showed smaller changes (12+4% and 11+3%). MVA size differed between genders, being related to body size but not to age (table, figures). MVA static and dynamic sizing by 3D-TTE are highly feasible. Our data may foster their implementation in clinical setting

Post-systolic shortening and circumferential strain as predictors of acute cellular refection in patients with recent orthotopic cardiac transplantation during dobutamine stress echocardiograpy

Purpose. Three-dimensional echocardiography (3DE) is more accurate and reproducible than conventional echocardiography in assessing left atrial (LA) volumes and function. Impairment of myocardial longitudinal strain has been recently correlated with fibrosis burden at both left ventricular (LV) and LA level. Our aim was to assess the relationship of LA longitudinal strain with LA function indices provided by 3DE, as well as their respective relationship with LV function in HCM. Methods: 32 pts with HCM (51+13 yrs, 20 men), 2D and 3D LA data sets were analyzed using GE EchoPac BT12 and TomTec 4D LA analysis software. 2 pts have been excluded due to poor quality LA acquisitions. 2D LA longitudinal strain at the end of reservoir phase (PALS) and LA strain at atrial contraction (PACS) obtained from 4- and 2-chamber views were averaged. 3D LA volumes (maximal, LAV max; minimal, LAVmin; and before atrial contraction, LAVpreA), total emptying fraction (total EF) and active emptying fraction (active EF) were semi-automatically computed using 3D echocardiography. LV mechanical function was assessed in terms of 2D longitudinal strain (2DLS - absolute values) and E/e\u2019average. Results: Impairment of LA longitudinal performance was correlated with LA volumes across all phases: LAVmax (r=-0.73 for PALS and PACS), LAV preA (r=-0.76 for PALS and -0.73 for PACS), LAVmin (r=-0.70 for PALS and -0.71 for PACS) (p,0.0001 for all). Modest correlations were identified for LA strain parameters with 3D LA total EF and active EF (r=0.57 and 0.56 for PALS; r=0.54 and 0.50 for PACS). LA strain parameters, as opposed to total EF and active EF, were correlated with LV 2DLS (r=0.74 for PALS and 0.54 for PACS) and inversely with E/e\u2019average (r=-0.38 for PALS and -0.42 for PACS). 3D LA phasic volumes were also correlated with LV 2DLS (r=-0.43 for LAVmax and r=-0.36 for LAVpreA, p,0.05) and filling pressures (r=-0.43, p=0.02 for all LA phasic volumes). Conclusion: InHCMpatients, there is only a modest relationship between LA longitudinal deformation and LA function parameters assessed by 3DE. LA 2D longitudinal strain and LA 3D volumes could be more useful clinical indicators of myocardial impairment inHCM than 3D LA emptying fraction

Concordance of left ventricular global longitudinal strain measurements between echocardiographic vendors

Purpose: Transthoracic 3D echocardiography (3DE) allows an unparalleled opportunity for quantifying the dynamic changes of the tricuspid annulus (TA). Accordingly, our aims were: (I) to assess the determinants of TA size during cardiac cycle in healthy subjects; (II) to propose an approach and timing for TA sizing using 3DE. Methods: In 50 healthy volunteers (45+14yrs, range 18-74, 27males, withnorisk factors, symptoms, signs or history of cardiovascular disease and on no medication), a fullvolume dataset of the right ventricle (RV) containing the tricuspid valve (TV) was acquired (Vivid E9,GEHealthcare).TAdiameters (septo-lateral, SL; antero-posterior, AP)and areas were measured on multiplanar images (Flexi-slice, EchoPac BT12, GE Healthcare) at 5 time points during the cardiac cycle: OS (onset of systole, at TV closure); MS (midsystole); ES (end-systole); ED (onset of diastole); LD (late diastole, after the P wave). RV volumes and ejection fraction (EF) were analyzed with commercial software (4D RV analysis, TomTec, D). Results: Temporal resolution of the 3D datasets was 32+4 vps (range 24-53). TA areas were more closely correlated with RV volumes and body surface area (BSA) than with either SL or AP diameters. TA areas increased during systole from OS (3.9+0.6 cm2/ m2) to ES (4.9+0.8 cm2/m2) and reached its largest area in LD (6.7+1.0 cm2/m2). All 5 TA areas were correlated with BSA (r range 0.57-0.62) and RV volumes (r ranges 0.53- 0.60 for end-diastolic volume and 0.43-0.50 for end-systolic volume, p,0.0001 for all). Indexed TA areas were not related to either age or gender. With multivariable analysis, both RVend-diastolic volume and BSA determined TA areas during systole and early diastole, while TA area at LD and at OS were independently related with BSA only. Conclusions: In healthy subjects, the main determinants of TA size are RV volume and BSA. The largest TA area occurs at LD and is independently related with BSA only. Therefore, normative values should be based on TAareas measured atLDand indexed forBSA. However, the rapid change in TA areas occurring from LD to OS underscores the importance of adequate temporal resolution of 3DE data sets for reliable TA measurement

Two-dimensional assessment of tricuspid annulus dynamics and diameters: study for new reference values

Background: Tricuspid annulus (TA) size and function plays an important role in decisionmaking process about the need of associated TA annuloplasty during left sided cardiac surgery. Recommendations about echo assessment of TA don\u2019t indicate the view and the timing where TA should be measured. Our aim was to study TA diameters and shortening in different 2D TTE views to assess the extent of their variability. Methods: Cross-sectional study of normal volunteers. TA was measured from 3 2DTTE views (apical 4-CH, LAX-RV inflow, SAX basal) at 5 time points during cardiac cycle. TA fractional shortening diameter was obtained as (TV opening early-filling \u2013 Mid-systole) / TV opening early-filling. Result: 100pts; 42%male; 44+13yrs. TA diameters are in the Table. Fractional shortening of TA was 22+7%, 18+8%, 31+16% in 4-CH, LAX-RV inflow and SAX basal views respectively. Conclusion: This study support new references values for TA evaluation using 2D TTE. Values vary according to 2D TTE view and cardiac cycle time, showing the dynamism and complex geometry of T

Right heart function by 3D-echocardiography and 2D-speckle tracking in scleroderma patients in absence of pulmonary hypertension

Purpose: Systemic Sclerosis (SSc) involves the right heart (RH) with the appearance of pulmonary hypertension (PH). Whether SSc can directly affect RH function in absence of PH is unknown. Recently, 3D-echocardiography (3DE) and 2D-speckle tracking (2D-STE) have been validated to assess heart chamber function and mechanics. Therefore, we used3DEand 2D-STE to assess right ventricular (RV) andright atrial (RA) function in patients with SSc without PH. Methods: 34 SSc patients without PH were compared with 34 age and gender-matched healthy volunteers. All subjects underwent a complete echocardiogram, including 3DE RV volumes and ejection fraction (EF) and global RV and RA longitudinal strain (Ls) by 2D-STE. Results: SSc patients demonstrated similar RV size with lower RV function but no differences about RV global Ls (p=NS) (Table). Pulmonary artery systolic pressure (PASP) and pulmonary vascular resistance (PVR) were higher in SSc patients (Table). RA appeared larger in patients, but with lower active contraction (RA-LsNeg). At bivariate analysis, PVR was inversely correlated with RV EF (r=-0.34, p= 0.008) and RA-LsNeg (r= -0.27, p=0.04) and directly correlated with RA maximum volume increase (r=0.31,p=0.012). Conclusions: a slightly increased afterload in SSc patients appared to be associated to an impairment of RV pump function, with normal RV myocardial mechanics, paralleled by an increase of RA volume with an impairment of RA active myocardial contraction