Systematic evaluation of multiple qPCR platforms, NanoString and miRNA-Seq for microRNA biomarker discovery in human biofluids.

Aberrant miRNA expression has been associated with many diseases, and extracellular miRNAs that circulate in the bloodstream are remarkably stable. Recently, there has been growing interest in identifying cell-free circulating miRNAs that can serve as non-invasive biomarkers for early detection of disease or selection of treatment options. However, quantifying miRNA levels in biofluids is technically challenging due to their low abundance.

A preliminary study for the assessment of PD-L1 and PD-L2 on circulating tumor cells by microfluidic-based chipcytometry.

Aim: Expression of PD-L1 in the tumor is associated with more favorable responses to anti-PD-1 therapy in multiple cancers. However, obtaining tumor biopsies for PD-L1 interrogation is an invasive procedure and challenging to assess repeatedly as the disease progresses.

Materials & Methods: Here we assess an alternative, minimally invasive approach to analyze blood samples for circulating tumor cells (CTCs) that have broken away from the tumor and entered the periphery.

Alterations in the hepatic transcriptional landscape after RNAi mediated ApoB silencing in cynomolgus monkeys.

The greater genomic conservation between humans and non-human primates (NHP) enables target validation studies for developing of therapeutic strategies for human diseases. Together with predicting activity and potential adverse clinical signs, the inclusion of NHP testing bequeaths to efficacy models for dose titration and pharmacodynamic effects. We have used lipid nanoparticle encapsulated siRNA to silence ApoB in the liver and assessed the phenotypic effects on serum lipids with various levels of hepatic ApoB mRNA knockdown in healthy lean cynomolgus monkeys.

Evaluation of cynomolgus monkeys for the identification of endogenous biomarkers for hepatic transporter inhibition and as a translatable model to predict pharmacokinetic interactions with statins in humans.

Inhibition of hepatic transporters such as organic anion transporting polypeptides (OATPs) 1B can cause drug-drug interactions (DDIs). Determining the impact of perpetrator drugs on the plasma exposure of endogenous substrates for OATP1B could be valuable to assess the risk for DDIs early in drug development. As OATP1B orthologs are well conserved between human and monkey, we assessed in cynomolgus monkeys the endogenous OATP1B substrates that are potentially suitable to assess DDI risk in humans.

Inverse relationship between LDL cholesterol and PCSK9 plasma levels in dyslipidemic cynomolgus monkeys: effects of LDL lowering by ezetimibe in the absence of statins.

Objectives: To assess the lipid-lowering efficacy of ezetimibe in dyslipidemic cynomolgus monkeys comparing two dosing methods, and to evaluate PCSK9 plasma levels during dyslipidemia induction by feeding a high-fat/high-cholesterol diet (HFD), ezetimibe (Zetia(®), Ezetrol(®)) treatment, ezetimibe washout, and HFD washout.

Methods And Results: Twenty dyslipidemic cynomolgus monkeys on HFD for seven months (LDL cholesterol 100-400 mg/dL) were randomized into two groups and treated with ezetimibe for two weeks, either by oral gavage or by using food treats. The lipid-lowering effects of ezetimibe were identical between the two groups.

Use of a bioamplification assay to detect nonselective recombinants and assess the genetic stability of oncolytic adenoviruses.

Detection of nonselective adenoviruses in tissue- or tumor-selective oncolytic adenovirus preparations presents a technical challenge because of the conditionally replication-competent nature of oncolytic adenoviruses. Although quantitative PCR has been used extensively for detecting specific genes that are likely present in nonselective recombinants, the actual biological activity of nonselective genetic recombinants has not been demonstrated. Therefore, a bioassay that amplifies nonselective adenoviruses through multiple passages in nonpermissive cells was developed to detect biologically active nonselective recombinants using CG7870, a prostate-specific oncolytic adenovirus.

Validation of cell density and viability assays using Cedex automated cell counter.

A method using Cedex automatic cell counter (Innovatis) to determine the cell density and viability of a whole cell-based immunotherapy product has been developed and validated for the assay performance characteristics including specificity, accuracy, precision, linearity, range, and robustness. Instrument-to-instrument variation due to intrinsic differences in handmade flow cells was also evaluated. For cell density, Cedex demonstrated acceptable specificity, accuracy and precision for cell densities ranging from 3.

Validation of a quantitative flow cytometer assay for monitoring HER-2/neu expression level in cell-based cancer immunotherapy products.

GVAX immunotherapy for prostate cancer is comprised of two genetically modified prostate cancer cell lines, CG1940 and CG8711, engineered to secrete granulocyte macrophage-colony-stimulating factor. As part of the matrix of potency assays, CG1940 and CG8711 are tested for the expression level of cell surface HER-2/neu using a quantitative flow cytometer assay. This assay reports the antibody binding capacity value of the cells as a measure of HER-2/neu expression using cells immediately after thawing from cryogenic storage.