STAT3 and lung cancer: MDK has also been shown to activate nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling [54] and signal transducer and activator of transcription 3 (STAT3) signaling [7,55], and it can increase the expression of yes-associated protein (YAP) and transcriptional coactivator with PDZ-binding motif (TAZ) of the Hippo/Yap pathway in lung cancer [35].