Transcriptomic profiling of 4T1 cells depleted for Id1/3 and Robo1

Id1 and its closely related family member Id3 are expressed by a diversity of stem and progenitor cells. We show that Id1/3 are required for the self-renewal and proliferation of triple negative breast cancer (TNBC) cells both in vitro and in vivo. Furthermore, we identified that Id1/3 negatively regulates the tumour suppressor gene Robo1. Depletion of Robo1 could rescue the proliferative defect induced by Id1/3 knockdown. To understand the mechanisms by which Robo1 rescues cell proliferation in Id1/3 depleted cells, we performed RNA-Sequencing on 4T1 cells with Dox-inducible Id1/3 KD and/or Robo1 depletion using siRNA. We conclude that following Id1/3 knockdown, Robo1 is induced and exerts anti-proliferative effects via suppression of a Myc transcriptional program. mRNA sequencing of 4T1 cells with 4 treatment groups: Control (Non-targeting siRNA [NT]), Id1/3 knockdown (NT+Dox), Robo1 knockdown (siRobo1), and Id1/3 + Robo1 knockdown (siRobo1+Dox). Experiments were performed in quadruplicate.