Induction and Diagnosis of Tumors in <em>Drosophila</em> Imaginal Disc Epithelia

Abstract

In the early stages of cancer, transformed mutant cells show cytological abnormalities, begin uncontrolled overgrowth, and progressively disrupt tissue organization. Drosophila melanogaster has emerged as a popular experimental model system in cancer biology to study the genetic and cellular mechanisms of tumorigenesis. In particular, genetic tools for Drosophila imaginal discs (developing epithelia in larvae) enable the creation of transformed pro-tumor cells within a normal epithelial tissue, a situation similar to the initial stages of human cancer. A recent study of tumorigenesis in Drosophila wing imaginal discs, however, showed that tumor initiation depends on the tissue-intrinsic cytoarchitecture and the local microenvironment, suggesting that it is important to consider the region-specific susceptibility to tumorigenic stimuli in evaluating tumor phenotypes in imaginal discs. To facilitate phenotypic analysis of tumor progression in imaginal discs, here we describe a protocol for genetic experiments using the GAL4-UAS system to induce neoplastic tumors in wing imaginal discs. We further introduce a diagnosis method to classify the phenotypes of clonal lesions induced in imaginal epithelia, as a clear classification method to discriminate various stages of tumor progression (such as hyperplasia, dysplasia, or neoplasia) had not been described before. These methods might be broadly applicable to the clonal analysis of tumor phenotypes in various organs in Drosophila.

THE YKI-CACTUS (IKBα)-JNK AXIS PROMOTES TUMOR GROWTH AND PROGRESSION IN DROSOPHILA

“…Consistent with previous reports, overexpression of Yki 3SA alone leads to hyperplasia, and homozygous loss of scrib induces neoplasia (42,54,55). When Yki 3SA scrib RNAi are co-expressed, multilayered metastatic tumors formed that degrade the basement membrane (Fig.…”

Protocol for assessing translation in living Drosophila imaginal discs by O-propargyl-puromycin incorporation

“…Untrained users can refer to published videos demonstrating dissections of wing and eye imaginal discs. 5 , 6 OPP incorporation. Remove the medium used during dissection and add fresh Schneider/FBS medium supplemented with Component A.…”

Single‐cell RNA sequencing in Drosophila: Technologies and applications

“…Thus, scRNA‐seq can be used to dissect tumor heterogeneity to understand tumor development and to devise treatment approaches. Drosophila wing disc has served as a model system for studying conserved mechanisms underlying tumorigenesis (Morimoto & Tamori, 2017). Ji et al (2019) performed scRNA‐seq on scrib mutant‐induced wing disc tumors and found that dynamic MAPK signaling activity control the transition from growth arrest to cell proliferation during tumorigenesis.…”