Triple negative breast cancer (TNBC) cells tend to display hyperactive PERK signaling in cases of distant metastasis, while ATF4 has been shown to induce MMP-2 and MMP-7 expression to promote ECM remodeling, therefore invasion and metastasis of esophageal squamous cell carcinoma and lymph node in vitro and in vivo [199,200]. The gene discussed is ATF4; the disease is esophageal squamous cell carcinoma.