May C. MORRIS
Institut des Biomolecules Max Mousseron,, France
Title: Fluorescent Peptide Biosensors for probing kinase activities – new tools for cancer diagnostics and drug discovery
Biography
Biography: May C. MORRIS
Abstract
Cyclin-dependant kinases (CDK/cyclins) constitute a class of heterodimeric kinases whose members play a central role in coordinating cell cycle progression and participate in a wide variety of essential biological processes including transcription, neuronal differentiation and metabolism (Lim and Kaldis 2013). These kinases are frequently hyperactivated in cancer cells and contribute to sustain unrefrained proliferation, thereby constituting established cancer biomarkers and attractive pharmacological targets for anticancer therapeutics (Asghar et al. 2015; Peyressatre et al. 2015). However, despite the oncological relevance of CDK/cyclin kinases, there are very few means of quantifying their relative activities to identify their hyperactivation.
In order to monitor the activity of these kinases in complex biological samples, such as cell extracts, tissue or tumour biopsies, and develop sensitive tools for diagnostic purposes, we have developed a toolbox of fluorescent biosensors through conjugation of environmentally-sensitive probes to synthetic modular polypeptides derived from kinase-specific substrates. These non-genetic biosensors offer a straightforward means of sensing subtle alterations in kinase activity in real time, in vitro and in living cells following facilited delivery by cell-penetrating peptides (Van TNN et al. 2014). These selective chemical probes allow to quantify differences between healthy and cancer cell lines, and in response to therapeutics. This technology is further suitable for probing and alterations in kinase activities in living cells, as well as in tissue samples and tumour biopsies. In particular, we have engineered a CDK4/Cyclin D-specific biosensor which we have implemented to quantify CDK4/Cyclin D activity in healthy and pathological skin biopsies (Prével et al. 2016), and a CDK5/p25-specific biosensor which provides means of monitoring this kinase in neuronal cells and assessing its hyperactivation in neuronal disorders such as glioblastoma.
Taken together, these fluorescent biosensors constitute attractive tools for cancer diagnostics, for monitoring cancer progression and evaluating response to therapeutics, whilst also enabling development of sensitive assays for high throughput screening and offering promising perspectives for drug discovery.