To determine whether HOXA1 affected the radiosensitivity of NPC, we performed immunohistochemistry assays to examine HOXA1 expression in 20 NPC samples from patients who experienced local recurrence within 5 years of radiotherapy and 50 samples from patients who achieved long-term recurrence-free survival (Figure 5A). The gene discussed is HOXA1; the disease is nasopharyngeal carcinoma.