Taking into account the high ribonucleolytic activity of RNase A [31] and given the fact that RNase A cannot have a direct cytotoxic effect on tumour cells by the cleavage of intracellular RNAs, due to its binding with cytosolic ribonuclease inhibitor [32], [33], we hypothesised that the enzyme affects the regulatory pathways of tumourigenesis through the cleavage of circulating oncogenic miRNAs and alteration of miRNA profile. This evidence concerns the gene RNASE1 and neoplasm.