RSPO1 and malignant colon neoplasm: In contrast to other reported studies where FGF2/FGFR signalling has been reported to be critical for the growth and self-renewal of colon cancer PDOs37, we report that the FGFR2c expressing PDXO models were not reliant on the inclusion of FGF2, EGF or the WNT3A, Noggin and R-Spondin supplements in the stem cell media.