Targeting Cancer Associated Fibroblasts/Tumor Cells Cross-Talk Inhibits Intrahepatic Cholangiocarcinoma Progression

Cancer associated fibroblasts (CAFs), mainly responsible for the desmoplastic reaction hallmark of intrahepatic Cholangiocarcinoma (iCCA), likely take a role in tumour aggressiveness and resistance to therapy, although the molecular mechanisms involved are unknown. Aim of the study is to investigate how targeting hCAF/iCCA cross-talk with a Notch1 inhibitor namely Crenigacestat would affect cancer progressionWe used different in vitro models in 2D and we established new 3D hetero-spheroids with iCCA cells and human (h)CAFs. Results were confirmed in a xenograft model, explanted tumoral tissues underwent transcriptomic and bioinformatic analysis. hCAFs/iCCA cross-talk sustains increased migration of both KKU-M213 and KKU-M156 cells, while Crenigacestat significantly inhibits only the cross-talk stimulated migration. Hetero-spheroids grow larger than homo-spheroids,formed by only iCCA cells. Crenigacestat significantly reduced invasion and growth of hetero- but not of homo-spheroids. In xenograft models, hCAFs/KKU-M213 tumours grew significantly larger than KKU-M213 tumours, but were significantly reduced in volume by Crenigacestat treatment, which also significantly reduced the fibrotic reaction. Interpretative phenomenological analysis of the transcriptome unveiled that genes of hCAFs/KKU-M213 but not of KKU-M213 tumours increased tumour lesions, and that Crenigacestat treatment inhibited the modulated canonical pathway. Cell cycle checkpoints were the most modulated pathway. In hetero-spheroids, the number of cells increased into G2/M cell cycle phase, while Crenigacestat significantly decreased the number into G2/M phase in hetero but not in homo-spheroids. The cross-talk hCAFs/iCCA is a new target for reducing cancer progression with drugs such as Crenigacestat.