TM4SF4 and cancer: Fractionated γ-radiation (2 Gy × 3 times or 2 Gy × 9 times), which enhances EMT and cancer stemness [28], also significantly up-regulated the cellular TM4SF4 and OPN, indicating that these proteins may be involved in the reinforcement of γ-radiation-induced stemness in cancer cells (Figure 1A).