After the first study demonstrating that RUNX3 has a tumor suppressive role [33], an increasing studies have reached the same conclusion, suggesting that RUNX3 also plays a tumor suppressive role in solid tumors, such as colon cancer [34], lung cancer [35], breast cancer [36], glioma [37], renal cancer [38], and hepatocellular carcinoma [39]. Here, RUNX3 is linked to lung cancer.