Topic of Presentation: "Single-cell RNA-seq Revealed Multiple Pathways of Therapy Resistance in Rectal Cancer” 

Description of Presentation: Colorectal cancer is the second leading cause of cancer-related death in Europe and United States and is often diagnosed at advanced stage.

However, less than 20% of rectal cancer (RC) patients have a complete response to neoadjuvant chemoradiotherapy (nCRT). To explore the mechanisms underlying therapy resistance in RC, we performed single-cell RNA sequencing (scRNA-Seq) on patient-derived xenograft models throughout the treatment to identify and characterize the therapy-resistant RC cells.

Single-cell analysis revealed five tumor cellular clusters with distinct gene expression profiles, including two therapy-resistant clusters.

Differently expressed gene analysis showed that genes associated with IL-17, TNF, MAPK, and ErbB pathways were up-regulated posttreatment, suggesting that they may be responsible for the therapy resistance of the tumor cell clusters.

These results shed light on the importance of these signaling pathways on the mechanisms of rectal cancer therapy resistance.