They analysed the distribution of claudins (1, 4, 5, and 7) and occludin in 97 patients with superficial and invasive front of tongue cancer, and found that claudins 1 and 7 were strongly expressed, claudin 4 moderately expressed, and claudin 5 the least expressed; occludin staining was irrelevant. The gene discussed is OCLN; the disease is tongue cancer.