When the obtained results are related to information on the expression of connexins in pathologically altered epithelia of the mammalian oral cavity (i.e., oral squamous cell carcinoma and tongue papilloma) and epidermis (i.e., psoriasis, viral warts, or palmoplantar keratoderma), an increase in the expression of Cx26 and Cx43 is noted [25,28,46,47,48,49]. The gene discussed is GJA1; the disease is oral cavity squamous cell carcinoma.