For Research Use Only. Not for Use in Diagnostic Procedures.
Dr. Emma Shanks and Dr. Lynn McGarry, The Beatson Institute for Cancer Research, Glasgow, UK
Dr. Emma Shanks (left) and Dr. Lynn McGarry (right).
In recent years, RNAi has become an increasingly powerful research tool and the introduction of siRNA screening libraries, targeted at the genomes of different species, has allowed real insight into previously unknown interactions.
The RNAi Screening Facility at the Beatson Institute for Cancer Research in Glasgow, UK, aims to facilitate the translation of existing cancer research into cancer treatments, and to enhance the efficacy of existing cancer drugs, potentially through a combinatorial therapeutic approach. The group's research is supported by the Operetta® High Content Imaging system with Harmony® analysis software.
Dr. Emma Shanks joined the Beatson Institute for Cancer Research in January 2011 as Head of Screening, to establish and manage the RNAi Screening Facility. Prior to this, Emma worked as a Postdoctoral Scientist within the Drug Discovery Unit at the University of Dundee. In her 5 years at the University of Dundee, she implemented new initiatives and managed over 15 screening projects, producing multiple publications. Emma has extensive experience in translating small-scale assays into High Throughput and High Content Screening assays, using a wide variety of platforms, for both small molecule and siRNA screens.
Dr. Lynn McGarry is the Principal Scientific Officer within the RNAi screening facility. Lynn joined the Beatson Institute for Cancer Research in 1990 and has many years’ experience in a wide variety of molecular biological techniques and image analysis, particular those relevant to gene expression studies, e.g. siRNA and genetic manipulation, and to invasion and motility studies, such as inverse invasion assay, immunocytochemistry, fluorescent imaging and timelapse microscopy. Lynn completed her Ph.D. at the Beatson Institute in 2004.
Researchers within the RNAi screening facility are interested in identifying novel interactions, pathways and mechanisms in specific types of carcinoma, by coupling the screening of human and mouse siRNA libraries with High Content Screening using the Operetta. This research will switch the cancer research spotlight to a genomic floodlight, allowing investigators to see the big picture.
Emma says: “We chose the Operetta to support our High Content Screening activities as it enables us to quantify cancer-specific cellular phenotypes using ready-made algorithms. Furthermore, the Harmony analysis software supplied with the Operetta gives fantastic visualization of images acquired within a well”.
“We use the Operetta primarily because of the software accessibility and online expert support; these are important levels of support which we feel are currently offered only by PerkinElmer. For example, we are currently developing cell migration, invasion and wound healing assays, and the Ready-To-Use Analysis methods in the software provide a template that we can modify and refine to our cell-specific phenotypes. The instrument itself is user friendly, and we can carry out a certain degree of maintenance independently of the engineer, which restricts instrument downtime.”
An illustration of the type of experiment that researchers will be performing using the Operetta can be found in figure 1. Cells expressing mutant p53 (a tumor suppressor protein) no longer form tight clusters in culture. This “cell scattering” is believed to correlate with the ability of cells to metastasize in vivo. The group will use siRNA screening on the Operetta to identify genes that mediate scattering and which are therefore potential targets for cancer therapies (figure 1).
Figure 1. Hepatocyte growth factor (HGF) is used as a positive control for cell scattering. Scattering can be quantified using Harmony software, where cells are grouped according to their proximity to one another, and a value of “cells per cluster” can be used to quantify the extent of scattering. Different colors are used to display which cells belong to each cluster.
Figure 2. Cells exogenously expressing a Rac guanine exchange factor (RacGEF), demonstrate altered morphology and a high degree of membrane ruffling. These are indications of metastatic potential in vivo. The Harmony analysis software can quantify the morphology changes using a width-to-length measurement, and can quantify membrane ruffling using a texture analysis function which identifies ridges in addition to other texture features. A: Myc-tagged RacGEF labeled with mouse anti-myc antibody and anti-mouse A488. B: Ridges are identified by the Harmony software and the intensity of ridges can be quantified. C: Ridges superimposed on cell image (created using exported images).