Precise levels of the Drosophila adaptor protein Dreadlocks maintain the size and stability of germline ring canals

A Drosophila RNAi screen reveals conserved glioblastoma-related adhesion genes that regulate collective cell migration

Migrating cell collectives are key to embryonic development but also contribute to invasion and metastasis of a variety of cancers. Cell collectives can invade deep into tissues, leading to tumor progression and resistance to therapies. Collective cell invasion is also observed in the lethal brain tumor glioblastoma (GBM), which infiltrates the surrounding brain parenchyma leading to tumor growth and poor patient outcomes. Drosophila border cells, which migrate as a small cell cluster in the developing ovary, are a well-studied and genetically accessible model used to identify general mechanisms that control collective cell migration within native tissue environments. Most cell collectives remain cohesive through a variety of cell–cell adhesion proteins during their migration through tissues and organs. In this study, we first identified cell adhesion, cell matrix, cell junction, and associated regulatory genes that are expressed in human brain tumors. We performed RNAi knockdown of the Drosophila orthologs in border cells to evaluate if migration and/or cohesion of the cluster was impaired. From this screen, we identified eight adhesion-related genes that disrupted border cell collective migration upon RNAi knockdown. Bioinformatics analyses further demonstrated that subsets of the orthologous genes were elevated in the margin and invasive edge of human GBM patient tumors. These data together show that conserved cell adhesion and adhesion regulatory proteins with potential roles in tumor invasion also modulate collective cell migration. This dual screening approach for adhesion genes linked to GBM and border cell migration thus may reveal conserved mechanisms that drive collective tumor cell invasion.

First person – Kara Stark

First Person is a series of interviews with the first authors of a selection of papers published in Journal of Cell Science, helping early-career researchers promote themselves alongside their papers. Kara Stark is first author on ‘Precise levels of the Drosophila adaptor protein Dreadlocks maintain the size and stability of germline ring canals’, published in JCS. Kara conducted the research described in this article while an undergraduate research assistant in Dr Lindsay Lewellyn's lab at Butler University, Indianapolis, IN. She is now a PhD student in the lab of Dr Zhao Zhang at Duke University, Durham, NC, investigating how transposon mobilization interacts with the immune system during development.