PSAP and colorectal carcinoma: As an initial proof-of-concept, we applied our strategy to the validation of a recently reported prognostic and predictive signatures for CRC based on the expression of six genes (BMP1, CD109, IGFBP3, LTBP1, NPC2, PSAP), which were identified through proteomics analysis of the secretoma of metastatic cancer cells and validated in transcriptomics datasets [30].