Similarly, Calsina et al. found the level of miR-21-3p miRNA to correlate with TSC2 expression and mTOR activation, suggesting that it could be a potential stratification biomarker for mTOR inhibitor treatment among patients with pheochromocytomal and paragangliomal neuroendocrine tumors [21]. This evidence concerns the gene MTOR and neuroendocrine neoplasm.