Likewise, it is essential to consider the sample size; for example, in a study with 85 samples (37 grade IV, 18 grade III, 24 grade II, and 6 grades II to III), it was found that Cx43 was expressed in more than 60% of glioblastomas [139], evidencing the large heterogeneity of the disease. Here, GJA1 is linked to glioblastoma.