CD274 and head and neck squamous cell carcinoma: For example: firstly, in lung cancer, the upregulation of PDL1 expression by ATM through the JAK1, 2/STAT3 signaling pathway promotes EMT and tumor metastasis, while the inhibition of ATM reduces PDL1 expression via the JAK/STAT3 signaling pathway, resulting in diminished EMT and suppressed tumor metastasis in mouse models (11); secondly, in head and neck squamous cell carcinoma, the loss of CMTM6, a regulator of PDL1 expression, inhibits PDL1 expression and leads to low EMT expression.