SWOG S1400C (NCT02154490)-A Phase II Study of Palbociclib for Previously Treated Cell Cycle Gene Alteration-Positive Patients with Stage IV Squamous Cell Lung Cancer (Lung-MAP Substudy).

ObjectiveLung-MAP (SWOG S1400) is a master platform trial assessing targeted therapies in squamous NSCLC. The objective of study C (S1400C) was to evaluate the response rate to palbociclib, a cyclin-dependent kinase 4 and cyclin-dependent kinase 6 inhibitor, in patients with cell cycle gene abnormalities.MethodsPatients with squamous NSCLC, a performance status of 0 to 2, and normal organ function who had progressed after at least one prior platinum-based chemotherapy with cyclin-dependent kinase 4 gene (CDK4) or cyclin D1 gene (CCND1), cyclin D2 gene (CCND2), or cyclin D3 gene (CCND3) amplifications on tumor specimens were eligible. The study was originally designed as a phase II/III trial comparing palbociclib with docetaxel, but it was modified to a single-arm phase II trial with the primary end point of response when immunotherapy was approved. If two or fewer responses were seen in the first 20 patients, then the study would cease enrollment.ResultsA total of 88 patients (9% of patients screened) were assigned to S1400C, and 53 patients enrolled (including 17 to receive docetaxel). One patient who had been registered to receive docetaxel was re-registered to receive palbociclib after progression while taking docetaxel. The frequencies of cell cycle gene alterations in the eligible patients taking palbociclib (n = 32) were as follows: CCND1, 81% (n = 26); CCND2, 9% (n = 3); CCND3, 6% (n = 2); and CDK4, 3% (n = 1). In all, 32 eligible patients received palbociclib. There were two partial responses (response rate 6% [95% confidence interval (CI): 0%-15%]), both with CCND1 amplification. Twelve patients had stable disease (38% [95% CI: 21%-54%]). The median progression-free survival was 1.7 months (95% CI: 1.6-2.9 months) and the median overall survival was 7.1 months (95% CI: 4.2-12.5).ConclusionPalbociclib as monotherapy failed to demonstrate the prespecified criteria for advancement to phase III testing

FRET studies of a landscape of Lac repressor-mediated DNA loops

DNA looping mediated by the Lac repressor is an archetypal test case for modeling protein and DNA flexibility. Understanding looping is fundamental to quantitative descriptions of gene expression. Systematic analysis of LacI•DNA looping was carried out using a landscape of DNA constructs with lac operators bracketing an A-tract bend, produced by varying helical phasings between operators and the bend. Fluorophores positioned on either side of both operators allowed direct Förster resonance energy transfer (FRET) detection of parallel (P1) and antiparallel (A1, A2) DNA looping topologies anchored by V-shaped LacI. Combining fluorophore position variant landscapes allows calculation of the P1, A1 and A2 populations from FRET efficiencies and also reveals extended low-FRET loops proposed to form via LacI opening. The addition of isopropyl-β-d-thio-galactoside (IPTG) destabilizes but does not eliminate the loops, and IPTG does not redistribute loops among high-FRET topologies. In some cases, subsequent addition of excess LacI does not reduce FRET further, suggesting that IPTG stabilizes extended or other low-FRET loops. The data align well with rod mechanics models for the energetics of DNA looping topologies. At the peaks of the predicted energy landscape for V-shaped loops, the proposed extended loops are more stable and are observed instead, showing that future models must consider protein flexibility

Normal values of regional left ventricular endocardial motion: multicenter color kinesis study. Am J Physiol Heart Circ Physiol 279: H2464– H2476

. Normal values of regional left ventricular endocardial motion: multicenter color kinesis study. Am J Physiol Heart Circ Physiol 279: H2464-H2476, 2000.-Our goal was to establish normal values for quantitative color kinesis indexes of left ventricular (LV) wall motion over a wide range of ages, which are required for objective diagnosis of regional systolic and diastolic dysfunction. Color-encoded images were obtained in 194 normal subjects (95 males, 99 females, age 2 mo to 79 yr) in four standard views. Quantitative indexes of magnitude and timing of systolic and diastolic function were studied for age-and genderrelated differences. Normal limits of all ejection and filling indexes were in a narrow range (Յ25% of the mean), with no major gender-related differences. Despite invariable ejection fractions, both peak filling and ejection rates decreased with age (30 and 20%, correspondingly) with a concomitant increase in mean filling and ejection times, resulting in fiveand twofold increases in the late to early filling and ejection ratios, correspondingly. Diastolic asynchrony increased with age (from 4.7 Ϯ 2.0 to 6.4 Ϯ 3.2 from the 2nd to 7th decade). The normal values of color kinesis indexes should allow objective detection of regional LV systolic and diastolic dysfunction. echocardiography; ultrasound imaging; ventricular function; wall motion COLOR KINESIS IS AN EMERGING echocardiographic technique based on acoustic quantification, which uses color-encoding to depict left ventricular (LV) systolic and diastolic endocardial motion However, a new technique, which detects abnormalities by comparing individual patient's data with normal values, relies on having these normal values established in a large sample of the normal population. Accordingly, normal values of different indexes of magnitude and timing of global and regional LV function derived from color kinesis images need to be established to allow objective detection of abnormalities with a high level of confidence. We also hypothesized that these indexes may be age and gender dependent, in which case normal values would need to be established for different demographic groups. Accordingly, the purpose of this collaborative multicenter effort was to establish normal values for magnitude and timing indexes of wall motion by acquiring and analyzing systolic and diastolic color kinesis images in a large group of normal subjects of both sexes over a wide range of ages. METHODS Study population. The protocol for this study was approved by the Institutional Review Board of the University of Chicago (protocol #9171). This protocol was initially designed to include eight age groups (8 decades between 0 and 80 yr) with a minimum of 20 normal subjects each (50% males and 50% Address for reprint requests and othe

Right ventricular dyssynchrony in patients with pulmonary hypertension is associated with disease severity and functional class

BACKGROUND: Abnormalities in right ventricular function are known to occur in patients with pulmonary arterial hypertension. OBJECTIVE: Test the hypothesis that chronic elevation in pulmonary artery systolic pressure delays mechanical activation of the right ventricle, termed dyssynchrony, and is associated with both symptoms and right ventricular dysfunction. METHODS: Fifty-two patients (mean age 46 ± 15 years, 24 patients with chronic pulmonary hypertension) were prospectively evaluated using several echocardiographic parameters to assess right ventricular size and function. In addition, tissue Doppler imaging was also obtained to assess longitudinal strain of the right ventricular wall, interventricular septum, and lateral wall of the left ventricle and examined with regards to right ventricular size and function as well as clinical variables. RESULTS: In this study, patients with chronic pulmonary hypertension had statistically different right ventricular fractional area change (35 ± 13 percent), right ventricular end-systolic area (21 ± 10 cm(2)), right ventricular Myocardial Performance Index (0.72 ± 0.34), and Eccentricity Index (1.34 ± 0.37) than individuals without pulmonary hypertension (51 ± 5 percent, 9 ± 2 cm(2), 0.27 ± 0.09, and 0.97 ± 0.06, p < 0.005, respectively). Furthermore, peak longitudinal right ventricular wall strain in chronic pulmonary hypertension was also different -20.8 ± 9.0 percent versus -28.0 ± 4.1 percent, p < 0.01). Right ventricular dyssynchrony correlated very well with right ventricular end-systolic area (r = 0.79, p < 0.001) and Eccentricity Index (r = 0.83, p < 0.001). Furthermore, right ventricular dyssynchrony correlates with pulmonary hypertension severity index (p < 0.0001), World Health Organization class (p < 0.0001), and number of hospitalizations (p < 0.0001). CONCLUSION: Lower peak longitudinal right ventricular wall strain and significantly delayed time-to-peak strain values, consistent with right ventricular dyssynchrony, were found in a small heterogeneous group of patients with chronic pulmonary hypertension when compared to individuals without pulmonary hypertension. Furthermore, right ventricular dyssynchrony was associated with disease severity and compromised functional class

Abnormal color flow signal traversing the myocardial wall: Not everything is what it appears to be

A case of a patient presenting with an acute myocardial infarction is presented. A transthoracic echocardiographic examination revealed an abnormal color flow signal that traversed the myocardial wall from a large inferior aneurysm and initially considered to be a ventricular septal defect. However, further echocardiographic manipulation utilizing modified views along with sequential injections of both agitated saline and Definity® proved very useful to identify a pseudoaneurysm. There was no further need for any other diagnostic test, and the patient was treated surgically, undergoing successful repair of the pseudoaneurysm as well as coronary artery bypass grafting of the left coronary artery