CGAS and cervical squamous intraepithelial neoplasia: Importantly, overexpression of p21 in cGAS-knockdown cells resulted in a decrease in the number of cells with CIN compared to that of cGAS-knockdown cells transfected with an empty pcDNA vector control (Fig. 7c); overexpression of p21 also abolished the precocious G2/M transition induced by cGAS depletion (Fig. 7g).