GJA1 and neoplasm: Namely, some authors showed higher Cx43 expression as a sign of progression to tumor (Brockmeyer et al., 2014), and higher Cx43 expression in tumors was regarded as a sign of worse prognosis, such as in case of esophageal SCC (Tanaka et al., 2016) and SqCC of oral cavity (Brockmeyer et al., 2014).