Assay development and screening for molecular targets and discovery

Division Of Basic Sciences - Nci

Investigators

Linked publications, trials & patents

Abstract

The goal of the Assay Development and Screening Section (ADSS) is to leverage the unique resources of the MTP to facilitate the discovery of bioactive substances, particularly natural products which can act as anticancer agents or other diseases of interest to the CCR/NCI. The ADSS advances this objective by acting as a central collaborative cog interfacing between basic science labs/programs in the CCR who have made fundamental discoveries and the chemical diversity of bioactive agents available through the efforts of the Natural Products Chemistry Section (NPCS) and Chemical Diversity and Development Section (CDDS) of the MTP. The central resource that ADSS brings to bridge these groups are high throughput screens that we internally develop which can be used to uncover modulators of molecular targets identified by the CCR collaborator. To succeed in this endeavor, ADSS has created a vertically integrated research environment where we work with the collaborating lab to assess the current understanding of the proposed screening target, we on-board and evaluate any available reagents from the collaborating lab as we optimize, miniaturize, and develop these reagents into an actionable high throughput screening platform capable of assaying our fractionated natural products holdings [>500,000 distinct substances in the form of the NCI Program for Natural Products Discovery (NPNPD) library]. Depending on the follow up capacity of the collaborators, ADSS will often work to internally establish orthogonal secondary assays which can be used to triage primary screening hits for target specificity and potency. Early leads that emerge from pilot screens of our pure compound holdings (~50,000 substances) are then used to validate these secondary assays as we begin NPNPD screening. Research efforts between ADSS and NPCS are then coordinated as NPNPD leads begin to emerge. Active compound isolation and structure elucidation result in the identification of assay active natural products which are then incorporated into the validation and characterization pipelines in both the MTP and collaborating laboratories as leads are evaluated to assess their potential for translation. During this review period, the efforts of ADSS were oriented around the following collaborative screening projects: Discovery of Diffuse Pleural Mesothelioma specific cytotoxic agents o Collaborator: Chuong Hoang, Thoracic Surgery Branch, NCI/CCR Inhibitors of Inositol-tetrakisphosphate-1-kinase (ITPK1) for metastasis suppression o Collaborator: Ji Luo, Laboratory of Cancer Biology and Genetics, NCI/CCR Chemical synergism with Topoisomerase 3-beta genetic manipulation o Collaborator: Yves Pommier, Developmental Therapeutics Branch, NCI/CCR Chemical Degraders as a therapeutic direction for prostate cancer oCollaborator: David Takeda, Genitourinary Malignancies Branch, NCI/CCR In addition, we remain productively engaged on several projects from the previous review period, including recent publications using lysine demethylase inhibitors in the context of alveolar rhabdomyosarcoma and compounds with activity in Merkel cell carcinoma. We also continue to pursue new avenues for collaboration with developing screens for aggressive renal cell carcinomas, kinase inhibitors characterization in pancreatic cancer, and a high throughput platform to discovery bioactive peptides and proteins. The collective efforts of ADSS and its collaborators has resulted in several publications during this review period, including a recently noted "Editor's Pick" in the Journal of Biological Chemistry, for our work identifying and characterizing the first reported inhibitors of the inositol kinase ITPK1. ADSS personnel have made significant contributions to both filed and accepted patent applications for our work discovering and elaborating the utility of the novel aplithianine class of kinase inhibitors. We have also participated in filing several Employee Invention Reports (EIRs) for our work characterizing bioactive agents for our topoisomerase 3-beta and diffuse pleural mesothelioma assays. ADSS screening platforms ar resulted primary screening results in excess of 1 million total screened wells. We have also provided in-depth operational and infrastructure support to the biochemical/biophysical screening efforts of the Protein Chemistry and Molecular Biology Section (PCMBS) with regard to the 7 assays that they are currently executing. Our research efforts on aplithianines lead to the creation of an aplithianine analog library which was made publicly available.