COL5A1 and cancer: For example, phosphatidylinositol (PI (38:4), m/z 885.5499) was strongly associated with extracellular matrix (ECM)-related genes, including COL5A2, COL5A1, and FN1. PI and its phosphorylated derivatives (phosphoinositides, PIPs) are known to play a crucial role in cancer development and progression, particularly through remodelling of the ECM in the tumour microenvironment63.