However, the down-regulation of CSNK1G2-AS1 in TGCTs and the correlation between CSNK1G2-AS1 and the prognosis of TGCT patients suggested that CSNK1G2-AS1 may resemble a tumor suppressor gene in TGCTs, contrary to the results of the cell experiments in vitro. The gene discussed is CSNK1G2; the disease is testicular germ cell tumor.