Tumor-derived Ilp8 and Upd3 contribute to intestinal progenitor cells depletion during cachexia in Drosophila larvae

Area of Science:

• Developmental Biology
• Cancer Biology
• Physiology

Background:

• Tumor development induces systemic effects impacting distant organs.
• In Drosophila larvae, wing disc tumors cause developmental delay and cachexia-like wasting.
• The impact of these paraneoplastic syndromes on the larval midgut remains largely unexplored.

Purpose of the Study:

• To investigate the effects of neoplastic tumors on Drosophila larval midgut development.
• To identify novel paraneoplastic phenotypes in the intestine.
• To screen for molecular mediators of tumor-induced midgut alterations.

Main Methods:

• Analysis of Drosophila larval midguts bearing neoplastic wing disc tumors.
• Quantification of midgut cell-type populations, including adult midgut precursors (AMPs) and niche cells.
• Genetic screening for signaling pathways involved in tumor-induced midgut changes.

Main Results:

• Neoplastic tumors induce significant alterations in larval midgut development.
• A depletion of adult midgut precursors (AMPs) and precocious differentiation of niche cells were observed.
• These midgut changes precede systemic muscle and adipose tissue atrophy, indicating a new paraneoplastic phenotype.
• Tumor-derived Ilp8 and Upd3 were identified as key mediators affecting AMP numbers and niche specification, respectively.

Conclusions:

• Drosophila neoplastic tumors trigger a novel paraneoplastic syndrome affecting midgut development.
• Tumor-induced midgut alterations involve stem cell depletion and niche cell disorganization.
• Ilp8 and Upd3 signaling pathways are critical mediators of these effects, highlighting potential therapeutic targets.