A Protocol for Genetic Induction and Visualization of Benign and Invasive Tumors in Cephalic Complexes of <em>Drosophila melanogaster</em>

Abstract

Drosophila has illuminated our understanding of the genetic basis of normal development and disease for the past several decades and today it continues to contribute immensely to our understanding of complex diseases [1][2][3][4][5][6][7] . Progression of tumors from a benign to a metastatic state is a complex event 8 and has been modeled in Drosophila to help us better understand the genetic basis of this disease 9. Here I present a simple protocol to genetically induce, observe and then analyze the progression of tumors in Drosophila larvae. The tumor induction technique is based on the MARCM system 10 and exploits the cooperation between an activated oncogene, Ras V12 and loss of cell polarity genes (scribbled, discs large and lethal giant larvae) to generate invasive tumors 9. I demonstrate how these tumors can be visualized in the intact larvae and then how these can be dissected out for further analysis. The simplified protocol presented here should make it possible for this technique to be utilized by investigators interested in understanding the role of a gene in tumor invasion. Video LinkThe video component of this article can be found at

Regulation of a serine protease homolog by the JNK pathway during thoracic development ofDrosophila melanogaster

“…Given that BM integrity is compromised during tumor metastasis and because JNK pathway is up-regulated in migrating tumors [4,8,25], it is attractive to suggest that SPH Scarface may play a role in tumor metastasis by regulating BM integrity. Future experiments will help us better understand the role of this SPH in tumor metastasis using a Drosophila model [26,27].…”

A novel link between FMR gene and the JNK pathway provides clues to possible role in malignant pleural mesothelioma

“…The complete genotype of flies used to test cooperation between oncogenic Ras V12 and dFMR overexpression is given below. The stocks used have been previously described [32,33].…”

Understanding Lunasin’s biology and potential as a cancer therapeutic by utilizingDrosophilagenetics

“…These properties of the MARCM system have been utilized to model tumor progression and to study the tumor microenvironment interaction. 55,56 Biomedical advances attributed to fruit fly research Drosophila has been used to model a variety of diseases and genetic disorders associated with aging, 57 neurological diseases such as Alzheimer's and Parkinson's, 37,58 and cancers. Drosophila thus provides a valuable model to understand disease states in humans and has led to many advances in modern medicine.…”

“…Mammalian homologs to Drosophila genes related to tumorigenesis Jones and Srivastava Lunasin and its potential as an anticancer therapeutic 525 .......................................................................................................................... migration of tumors. One such modeling makes use of the Ras V12 /lgl À/À genotype 56,75. Ras is an oncogenic protein and Ras V12 codes for an activated isoform of the protein.…”

“…Flies overexpressing Ras V12 exhibit benign, non-metastatic tumors. However, when Ras V12 clones are also mutant for lethal giant larvae, a tumor suppressor encoded by the gene lgl, aggressive metastatic tumors result 56,75.…”