GSE134074
Genome-wide CRISPR-Cas9 screen identifies SLC1A3 as a key contributor to L-asparaginase Resistance in Solid tumors
L-asparaginase (ASNase) has been incorporated in the treatment of acute lymphoblastic leukemia for decades. However, intolerable toxicity due to increasing ASNase dosage has been observed in clinical trials with solid tumors. Here, we performed a genome-wide CRISPR-Cas9 functional screen in ASNase-resistant PC3 prostate cancer cells and identified SLC1A3, an aspartate transporter highly expressed in brain tissues but also in several tumor types. Interestingly, combined ASNase treatment and SLC1A3 inhibition caused cell cycle arrest and metabolic alterations in the urea cycle, nucleotide synthesis, energy production by both TCA cycle and glycolysis, and impaired lipid metabolism. Additionally, the introduction of SLC1A3 into SLC1A3-negative mouse and human breast cancer cells increased tumor and metastasis burden, and promoted ASNase tolerance in vitro and in vivo. These findings uncover an important role of SLC1A3 in ASNase resistance and indicated limited aspartate uptake for enhancement of ASNase efficacy with solid tumors. Overall design: PC3, DU145 and DU145-SLC1A3oe cells were cultured under 4 conditions for 3 days. Total RNA were extracted and libraries were prepared following TruSeq Stranded mRNA sample preparation kit (Illumina).