Tobioka et al. [17] found occludin expression in 100% of 42 endometrioid endometrial carcinomas (our study: 98.3%), Dos Santos et al. [24] in 97.5% of 602 serous ovarian carcinomas (our study: 98.2%) and in 46% of 87 mesotheliomas (our study: 58.3%), Montaro et al. [26] in 70.2% of 60 oral squamous cell carcinomas (our study: 69.8%), Billings et al. [34] in 45.7% of 35 synovial sarcomas (our study: 36.4%), and Nakanishi et al. [35] in 6.1% of non-invasive urinary bladder cancers (our study: 1.7%). This evidence concerns the gene OCLN and oral cavity squamous cell carcinoma.